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1
Ekeu-wei, Iguniwari, George Blackburn, and Philip Pedruco. "Infilling Missing Data in Hydrology: Solutions Using Satellite Radar Altimetry and Multiple Imputation for Data-Sparse Regions." Water 10, no. 10 (October 20, 2018): 1483. http://dx.doi.org/10.3390/w10101483.
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In developing regions missing data are prevalent in historical hydrological datasets, owing to financial, institutional, operational and technical challenges. If not tackled, these data shortfalls result in uncertainty in flood frequency estimates and consequently flawed catchment management interventions that could exacerbate the impacts of floods. This study presents a comparative analysis of two approaches for infilling missing data in historical annual peak river discharge timeseries required for flood frequency estimation: (i) satellite radar altimetry (RA) and (ii) multiple imputation (MI). These techniques were applied at five gauging stations along the floodprone Niger and Benue rivers within the Niger River Basin. RA and MI enabled the infilling of missing data for conditions where altimetry virtual stations were available and unavailable, respectively. The impact of these approaches on derived flood estimates was assessed, and the return period of a previously unquantified devastating flood event in Nigeria in 2012 was ascertained. This study revealed that the use of RA resulted in reduced uncertainty when compared to MI for data infilling, especially for widely gapped timeseries (>3 years). The two techniques did not differ significantly for data sets with gaps of 1–3 years, hence, both RA and MI can be used interchangeably in such situations. The use of the original in situ data with gaps resulted in higher flood estimates when compared to datasets infilled using RA and MI, and this can be attributed to extrapolation uncertainty. The 2012 flood in Nigeria was quantified as a 1-in-100-year event at the Umaisha gauging station on the Benue River and a 1-in-50-year event at Baro on the Niger River. This suggests that the higher levels of flooding likely emanated from the Kiri and Lagdo dams in Nigeria and Cameroon, respectively, as previously speculated by the media and recent studies. This study demonstrates the potential of RA and MI for providing information to support flood management in developing regions where in situ data is sparse.
2
Vardanyan, Trahel G., Natalia L. Frolova, and Hrachuhi S. Galstyan. "The Characteristics Of Extreme Maximum Runoff Of The Rivers Of Armenia In The Context Of Global Climate Change." GEOGRAPHY, ENVIRONMENT, SUSTAINABILITY 14, no. 1 (April 5, 2021): 196–208. http://dx.doi.org/10.24057/2071-9388-2020-122.
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The study concerned the analysis of temporal and spatial variability of floods in the Republic of Armenia (RA). While there are number of reports on flood formation of rivers in RA, the literature lacks results on using nonparametric test results to analyze this disastrous phenomenon. For that purpose, the dynamics of changes in extreme maximum instantaneous runoff, as well as air temperature and precipitation database was evaluated and compared between 1960–2012 for 27 hydrometrical observational and 35 meteorological stations in RA. The Mann-Kendall test with consideration of the autocorrelation function was employed as a non-parametric testto identify any present trends. An increasing tendency of air temperature, decreasing tendency of the atmospheric precipitation and extreme maximum instantaneous river runoff were identified in the studied river-basins. As expected, the warming climate contributed to a gradual melting of accumulated snow in the river-basins in winter, resulting in changes in the extreme maximum instantaneous runoff of the rivers in spring, which significantly reduces the risk of the flood occurrence. Thus, it can be claimed that almost all the river basins of Armenia have a tendency to reduce the risk of floods due to global climate change.
3
Barth, A., M. Jurk, and D. Weiß. "Concentration and distribution patterns of naturally occurring radionuclides in sediments and flood plain soils of the catchment area of the river Elbe." Water Science and Technology 37, no. 6-7 (March 1, 1998): 257–62. http://dx.doi.org/10.2166/wst.1998.0760.
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The impact of uranium mining and milling as well as that of traditional mining activities on river sediments and flood plain soils in the catchment area of the river Elbe was investigated over the years 1994 to 1995. Contamination resulting from mining activities has been identified by comparing the median values for the measured radionuclides, and by establishing the ratio between Ra-226 and Ra-228. The transport and deposition of contaminated materials as a result of high water events, and river discharge of waste water from mining and milling facilities, can be considered to be the main paths of sediment and soil contamination. Sediments and flood plain soils located in the vicinity of former uranium mining and milling sites are primarily influenced by discharges of waste water. Long distance transport and deposition at dams, barrages and on flood plains has mainly been caused by high water events. In many cases the radionuclide concentrations were higher in the subsurface layer than in the top layer of flood plain soil. Due to termination of uranium mining and milling activities, no significant contamination of newer or fresh sediments was found. Radiation exposure arising in relation to angling or walking on flood plains is low.
4
Chen, Y. S. "The Flood Motif as a Stylistic and Temporal Device in Sumerian Literary Traditions." Journal of Ancient Near Eastern Religions 12, no. 2 (2012): 158–89. http://dx.doi.org/10.1163/15692124-12341236.
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Abstract Recent scholarship suggests the Flood motif and its literary representations may have emerged and developed relatively late in Sumerian literary traditions. To investigate how the Flood motif gained its entry in the literary traditions, the current study traces the dissemination of the temporal expression eĝir a-ma-ru ba-ur3-ra-ta “After the Flood had swept over . . .” and its variants in Sumerian mythological and chronographic sources during the Old Babylonian period. This study seeks to demonstrate that when the Flood motif first emerged explicitly in Sumerian literary traditions it manifested as an innovative stylistic and temporal device for introducing the primeval time of origins as well as for marking the (re-)beginning of time. Coming to grips with this initial stage of development of the Flood motif will shed important light on some key conceptual and literary processes through which the Flood motif and its mythological and chronographic representations formed and evolved during the Old Babylonian period.
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Belmaker, Reuven, Mordechai Stein, Yoseph Yechieli, and Boaz Lazar. "Controls on the Radiocarbon Reservoir Ages in the Modern Dead Sea Drainage System and in the Last Glacial Lake Lisan." Radiocarbon 49, no. 2 (2007): 969–82. http://dx.doi.org/10.1017/s0033822200042831.
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Carbon isotopic and chemical compositions of freshwaters feeding the Dead Sea and the Sea of Galilee (i.e. perennial streams and floods along their stream profiles) were used to constrain the factors that dictate the reservoir ages (RA) of these lakes and the last glacial Lake Lisan. Runoff waters are characterized by high Ca2+, Mg2+, alkalinity, and radiocarbon contents (67–108 pMC), suggesting a major role for 14C atmospheric exchange reactions (carbonate rock dissolution alone will result in lower pMC values). These exchange processes were corroborated by dissolved inorganic carbon (DIC) and δ13C trends throughout the flood profile. During the evolution from rain to incipient runoff, the 14CDIC of the water increases and is accompanied by a DIC increase and δ13CDIC decrease, suggesting an addition of soil CO2, which is characterized by light δ13C and high 14C content. When incipient runoffs evolve to floods, the opposite trends are observed.It appears that the Sea of Galilee, the Dead Sea, and its last glacial precursor, Lake Lisan, maintained uniform but specific RAs of 0.8 ± 0.1, 2.3 ± 0.1, and 1.6 ± 0.3 kyr, respectively. However, applying the 14C contents of modern Dead Sea water sources to the water mass balance of Lake Lisan reveals that the RA of Lake Lisan is higher than that predicted by the mass balance. This discrepancy may reflect enhanced dissolution of carbonatic dust, changes in the amount of 14C exchanged in Judean Desert floods, or variations in the contribution of brine and saline springs. Furthermore, the small fluctuations in the Lisan RA (1.6 ± 0.3 kyr) may reflect small, short-term changes in the relative contributions of these sources.
6
Yadi, Ilman Zuhri, and Suzi Oktavia Kunang. "CELAH IPV6 ROUTER ADVERTISEMENT PADA SISTEM OPERASI WINDOWS." Jurnal Ilmiah Matrik 20, no. 2 (January 25, 2019): 85–94. http://dx.doi.org/10.33557/jurnalmatrik.v20i2.111.
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Dengan makin berkurangnya jumlah IPv4 yang tersedia maka perlu dipertimbangkan penggunaan IPv6. Akan tetapi IPv6 sendiri masih memiliki celah keamanan antara lain celah keamanan serangan flooding Router Advertisement palsu. Router Advertisement flood sendiri adalah merupakan serangan IPv6 DoS di jaringan lokal. Serangan ini membanjiri segmen jaringan lokal dengan malicious Router Advertisement untuk menggantikan entri routing yang sah pada antarmuka suatu host. Tujuan dari penelitian ini adalah mempelajari respon Sistem Operasi dengan platform Windows terhadap serangan IPv6 Router Advertisement di jaringan, serta memberikan rekomendasi solusi untuk menutup celah keamanan tersebut. Pengujian serangan dilakukan dengan dua tahapan yaitu pengiriman paket flood RA dengan single prefix dan multi prefix.
7
Khawaja, A. H., M. Jahanzaib, and T. A. Cheema. "High-speed machining parametric optimization of 15CDV6 HSLA steel under minimum quantity and flood lubrication." Advances in Production Engineering & Management 15, no. 4 (December 24, 2020): 403–15. http://dx.doi.org/10.14743/apem2020.4.374.
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High-speed machining (HSM) maintains a high interest in the preparation of metal parts for optimum results, but with the application of HSM, the sustainability issue becomes important. To overcome the problem, minimum quantity lubrication (MQL) during HSM is one of the innovative and challenging tasks during conventional cutting (milling) to improve quality, productivity, and strength under the umbrella of sustainability. The objective of this research is to achieve sustainable machining by simultaneously optimizing sustainable machining drivers during the HSM of 15CDV6 HSLA steel under MQL and flood lubrication. The response surface methodology has been applied for the development of mathematical models and selecting the best combination of process parameters to optimized responses, i.e. surface roughness, material removal rate, and strength. Optimization associated with sustainability produced compromising optimal results (Min. Ra 0.131 µm, Max. MRR 0.64 cm3/min, and Max. ST 1132 MPa) at the highest cutting speed 270 m/min and the lowest feed rate 0.09 mm/rev and depth of cut 0.15 mm under MQL. The comparative investigation exposed that significant improvement in Ra (1.1-16.6 %) and ST (1.3-2.3 %) of the material using MQL has been witnessed and gives a strong indication that MQL is the best substitute than the flood lubrication. The scientific contribution of the approach is to develop mathematical models under MQL and flood lubrication that will aid practitioners to choose input parameters for desired responses without experimentations. The work would be beneficial in the field of aviation, defense, and aeronautical applications due to the excellent mechanical properties of 15CDV6 HSLA steel.
8
Mohamed Nor, Zulhilmi, and Azman Ab. Rahman. "Hujan dan Banjir dalam Hadis Nabi Saw." Journal of Fatwa Management and Research 8, no. 1 (July 12, 2018): 9–28. http://dx.doi.org/10.33102/jfatwa.vol8no1.47.
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Natural disaster happened around the world causing destruction to the environment and mankind. All of these natural disasters also happened during the time of Prophet and his Companions. Natural disasters that often experienced in our country is flood. This phenomenon that happened previously has causing chaos to many people. The floods began with heavy rain, spilled into the river and cause it to overflow. This article will analyse the views of Prophet in regards to the issue of the floods. It commenced with the situation before, during and after of the rain and the effects of continuous rain. Some hadith of Prophet will be collected and analysed guided with the view of contemporary scholars. This research is expected to expose the actions of Prophet to the phenomenon of rain and floods. It also shall become a guideline and a starting point for Muslim to deal about completion of the rain and flood disasters. Generally, the views of Prophet about the flood are very minimising. It corresponds to the times, places and circumstances in Mecca and Medina during that time, when the rain is simply related to the range by way of the Prophet faced and through its.Keywords: rain, flood, damages, natural disaster, hadith of Prophet
Abstrak
Dewasa ini kita melihat banyak berlaku bencana alam di merata tempat di dunia. Kesemua bencana alam ini pernah diketahui atau disaksikan oleh Nabi SAW dan para sahabat Baginda RA. Antara bencana alam yang sering dialami di negara kita adalah banjir, kejadian banjir yang melanda negara tidak lama dahulu amat meresahkan semua pihak. Banjir ini dimulai dengan hujan lebat yang berterusan, lalu mengakibatkannya bertakung atau melimpah. Artikel ini akan cuba mengemukakan pandangan dan sabdaan Nabi SAW berkaitan dengan hujan yang menjadi sebab kepada banjir dan seterusnya melihat saranan Baginda atau perlakuan terhadap banjir yang melanda. Ia dimulakan dengan situasi sebelum, semasa dan selepas berlakunya hujan dan kesan daripada hujan yang berterusan. Beberapa hadis Nabi SAW yang berkaitan akan dikumpulkan dan dianalisa isi kandungannya serta dikukuhkan dengan pandangan ulama muktabar. Diharapkan artikel ini dapat menyingkap perbuatan dan sabdaan Nabi SAW terhadap fenomena hujan dan banjir dan seterusnya menjadi suatu pedoman dan titik permulaan kepada umat Islam untuk berhadapan dan mula mencari jalan penyelesaian kepada bencana hujan dan banjir. Didapati secara umumnya, sentuhan Nabi SAW terhadap banjir amat minima, ia sesuai dengan zaman, tempat dan keadaan di Mekah serta Madinah pada ketika itu, manakala berkaitan hujan hanyalah berkisar dengan cara Nabi SAW berhadapan dan melaluinya. Kata kunci: hujan, banjir, kemusnahan, bencana alam, sunnah Nabi SAW
9
Mohd Subri, Irwan, Wan Mohd Fazrul Azdi Wan Razali, Walid Mohd Said, Nisar Mohammad Ahmad, Amir Shaharuddin, Mohd Aizuddin Abdul Aziz, Mohd Azhar Ibrahim Residi, Mohd Nur Adzam Rasdi, Syadiyah Abdul Shukor, and Bilal Jailani. "Isu-Isu Fiqh di Pusat Pemindahan Mangsa Banjir: Kajian Perintis di Daerah Temerloh, Pahang." Journal of Fatwa Management and Research 8, no. 1 (July 12, 2018): 29–48. http://dx.doi.org/10.33102/jfatwa.vol8no1.48.
Full textAbstract:
Natural disaster happened around the world causing destruction to the environment and mankind. All of these natural disasters also happened during the time of Prophet and his Companions. Natural disasters that often experienced in our country is flood. This phenomenon that happened previously has causing chaos to many people. The floods began with heavy rain, spilled into the river and cause it to overflow. This article will analyse the views of Prophet in regards to the issue of the floods. It commenced with the situation before, during and after of the rain and the effects of continuous rain. Some hadith of Prophet will be collected and analysed guided with the view of contemporary scholars. This research is expected to expose the actions of Prophet to the phenomenon of rain and floods. It also shall become a guideline and a starting point for Muslim to deal about completion of the rain and flood disasters. Generally, the views of Prophet about the flood are very minimising. It corresponds to the times, places and circumstances in Mecca and Medina during that time, when the rain is simply related to the range by way of the Prophet faced and through its.
Keywords: rain, flood, damages, natural disaster, hadith of Prophet
Abstrak
Dewasa ini kita melihat banyak berlaku bencana alam di merata tempat di dunia. Kesemua bencana alam ini pernah diketahui atau disaksikan oleh Nabi SAW dan para sahabat Baginda RA. Antara bencana alam yang sering dialami di negara kita adalah banjir, kejadian banjir yang melanda negara tidak lama dahulu amat meresahkan semua pihak. Banjir ini dimulai dengan hujan lebat yang berterusan, lalu mengakibatkannya bertakung atau melimpah. Artikel ini akan cuba mengemukakan pandangan dan sabdaan Nabi SAW berkaitan dengan hujan yang menjadi sebab kepada banjir dan seterusnya melihat saranan Baginda atau perlakuan terhadap banjir yang melanda. Ia dimulakan dengan situasi sebelum, semasa dan selepas berlakunya hujan dan kesan daripada hujan yang berterusan. Beberapa hadis Nabi SAW yang berkaitan akan dikumpulkan dan dianalisa isi kandungannya serta dikukuhkan dengan pandangan ulama muktabar. Diharapkan
artikel ini dapat menyingkap perbuatan dan sabdaan Nabi SAW terhadap fenomena hujan dan banjir dan seterusnya menjadi suatu pedoman dan titik permulaan kepada umat Islam untuk berhadapan dan mula mencari jalan penyelesaian kepada bencana hujan dan banjir. Didapati secara umumnya, sentuhan Nabi SAW terhadap banjir amat minima, ia sesuai dengan zaman, tempat dan keadaan di Mekah serta Madinah pada ketika itu, manakala berkaitan hujan hanyalah berkisar dengan cara Nabi SAW berhadapan dan melaluinya.
Kata kunci: hujan, banjir, kemusnahan, bencana alam, sunnah Nabi SAW.
10
Oanh, Phạm Thị Tố. "FORECASTING THE RISK OF FLOODING WHEN THE PAC CAP HYDROPOWER DAM BREAKS ON NA RI RIVER IN BAC KAN PROVINCE." TNU Journal of Science and Technology 225, no. 13 (November 30, 2020): 94–100. http://dx.doi.org/10.34238/tnu-jst.3487.
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Thủy điện Pác Cáp được phê duyệt chủ trương đầu tư tại Quyết định số 96/QĐ-UBND ngày 18/01/2018 trên sông Na Rì, huyện Na Rì tỉnh Bắc Kạn với công suất 6 MW. Trong quá trình thi công, vận hành 02 tổ máy, vỡ đập có thể xảy ra khi lũ tràn đỉnh đập, nứt ngang nứt dọc đập, trượt mái thượng và hạ lưu đập,… Nghiên cứu này tập trung mô phỏng sự cố vỡ đập thông qua việc sử dụng mô hình Mike Flood. Kết quả chỉ ra rằng: chiều sâu ngập lớn nhất >10 m với diện tích ngập lụt khoảng 15 ha trong đó chủ yếu là đất trồng cây hàng năm, đất lúa và rừng sản xuất; chiều sâu ngập từ 4-10 m chiếm khoảng 10 ha; chiều sâu từ 1-4 m ngoài các loại đất rừng và đất nông nghiệp bị ngập còn nhấn chìm khoảng 30 ngôi nhà của xã Lương Thành và Lam Sơn thuộc huyện Na Rì và một số công trình hạ tầng khác. Kết quả nghiên cứu là cơ sở đưa ra các biện pháp phòng tránh nhằm giảm thiểu tác hại đến vùng hạ lưu công trình, đồng thời cũng là căn cứ để xác định trách nhiệm của Nhà máy trong quá trình bồi thường nếu để sự cố xảy ra.
11
Bryndal, Tomasz. "The River Systems in Small Catchments in the Context of the Horton’s and Schumm’s Laws – Implication for Hydrological Modelling. The Case Study of the Polish Carpathians." Quaestiones Geographicae 34, no. 1 (March 1, 2015): 85–98. http://dx.doi.org/10.1515/quageo-2015-0008.
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Abstract In ungauged catchments, flood hydrographs are usually simulated/reconstructed by simple rainfall-runoff and routing models. Horton’s and Schumm’s ratios serve as the input data for many of these models. In this paper, more than 800 Carpathian catchments (up to 35.2 km2 in area) were investigated in context of the “Horton’s and Schumm’s laws”. Results reveal that the “law of stream number” and “law of stream areas” are fulfilled in almost all catchments. The mean that values of the bifurcation ratio (RB) and the area ratio (RA) reach 3.8 and 4.8, respectively, and are thus comparable to values reported in other regions of the world. However, the “law of stream lengths” is not fulfilled in more than half of the catchments, which is not consistent with many theoretical studies reported in the literature. Only 383 (48%) catchments fulfill the “law of stream length”, with the mean value of the length ratio (RL)=2.3. There was no relationship found between the geological/geomorphological settings that influence river system development and the spatial distribution of catchments where the “law of stream length” was or was not was fulfilled. A similar conclusion was reached for the spatial distribution of the RB, RL, and RA ratios. These results confirmed that the use of Horton’s and Schumm’s ratios for the evaluation of the influence of geological/geomorphological settings on the river system development is limited. Among the lumped hydrological models, those requiring the RB, RL, and RA ratios have been extensively studied over last decades. This study suggests that the application of these models may be limited in small catchment areas; therefore, more attention should be placed on the development of hydrological models where the RB, RL, and RA ratios are not necessary.
12
Jócsák, Ildikó, Magdolna Droppa, Gábor Horváth, Károly Bóka, and Eszter Vozáry. "Cadmium- and Flood-Induced Anoxia Stress in Pea Roots Measured by Electrical Impedance." Zeitschrift für Naturforschung C 65, no. 1-2 (February 1, 2010): 95–102. http://dx.doi.org/10.1515/znc-2010-1-216.
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Electrical impedance measurement - complex resistance in the presence of alternating current - is a useful tool for the investigation of structural characteristics of solid materials but also for plant tissues. This measurement is easily done: only two electrodes are inserted into the plant tissue, so it can be considered as a non-invasive technique and it may be a successful method for detecting structural changes in plants caused by environmental stresses. The effects of fl ood and cadmium stress were investigated by electrical impedance measurement, because both of them cause structural changes in plant tissues. Apoplasmic resistance (Ra), symplasmic resistance (Rs), and membrane capacitance (Cm) of pea roots were calculated. In the fi rst fi ve days of fl ood treatment, the Rs and Cm values of roots decreased drastically. In case of cadmium treatment, the Rs and Cm values of roots showed an increasing tendency supposedly as a consequence of the enhanced membrane rigidity, the thickened cell walls and decreased growth phenomena caused by the heavy metal. There also was a remarkable difference in cadmium accumulation patterns and in the changes of the calculated parameters amongst anoxic and aerated seedlings. This initial work revealed that the development of stress caused by two environental stress agents, cadmium and fl ood, can be followed by electrical impedance measurement.
13
Gao, Yanjun, and Yongqiang Zhang. "Effects of the Three Gorges Project on Runoff and Related Benefits of the Key Regions along Main Branches of the Yangtze River." Water 11, no. 2 (February 4, 2019): 269. http://dx.doi.org/10.3390/w11020269.
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The Three Gorges Project (TGP) is the largest hydroelectric project in the world. It is crucial to understand the relationship between runoff regime changes and TGP’s full operation after 2009 in the Yangtze River Basin (YRB). This paper defines core, extended and buffer areas of YRB, analyzes the effects of TGP on runoff anomaly (RA), runoff variation (RV) and change of coefficient of variation (CCV) between two periods (2003–2008 and 2009–2016), takes percentage of runoff anomaly (PRA) as the evaluation standard, assures alleviation effect on severe dry and wet years of the research area, and finally summarizes related benefits of flood control from TGP. Our results indicate the inter-annual fluctuation of runoff in the core and extended areas expanded, but reduced in the buffer areas, and the frequencies of severe dry and wet years alleviated in the buffer, core and extended areas. Generally, the extended and core areas become less wet, and the buffer areas become less dry. The RV and CCV are both strengthened in the extended and core areas, but are weakened in the buffer areas, and RV is well positively correlated (R2 = 0.80) to CCV. Furthermore, the main benefits of TGP on flood control are remarkable in the reduction of disaster affected population, the decrease of agricultural disaster-damaged area, and the decline of direct economic loss. However, due to torrentially seasonal and non-seasonal precipitation, the sharp rebounds of three standards for Hubei and Anhui occurred in 2010 and 2016, and the percentage of agricultural damage area of five regions in the core and extended areas did not decline synchronously and performed irregularly. Our results suggest that the five key regions along the main branches of the Yangtze River should establish a flood control system and promote the connectivity of infrastructures at different levels to meet the significant functions of TGP. It is a great challenge for TGP operation to balance the benefits and conflicts among flood control, power generation and water resources supply in the future.
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Bork, Carlos Alberto Schuch, Janaina Fracaro Souza Gonçalves, and Jefferson Oliveira Gomes. "The Jatropha curcas vegetable base soluble cutting oil as a renewable source in the machining of aluminum alloy 7050-T7451." Industrial Lubrication and Tribology 67, no. 2 (March 9, 2015): 181–95. http://dx.doi.org/10.1108/ilt-09-2014-0090.
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Purpose – This article aims to collect data on the aluminum alloy 7050-T7451 machinability used in the manufacturing of aeronautical structures, using the combination of the jatropha vegetable-base soluble cutting oil in relation to the canola vegetal and semisynthetic mineral oils and the technique to apply cutting fluid by flood in relation to the Minimum Quantity Lubrication (MQL) in the milling process (HSM – high-speed machining). Design/methodology/approach – It was observed that the jatropha vegetal cutting oil presented the best results in relation to requirements for lubrication, superficial mean roughness (index Ra) and shape errors in relation to the other oils in both the techniques to apply fluid which were tested. Comparing the application techniques, the jatropha vegetal oil offered an increase in the life span of the cutting tool, using the flood technique, exceeding in almost six times the machined length of the cutting tool in relation to the MQL technique in the same process conditions. Findings – The Jatropha vegetable-base cutting oil, besides being produced from a renewable source, has inherent characteristics that can help attain a sustainable manufacturing, mainly with the use of the flood technique to apply cutting fluid in the aluminum alloy 7050-T7451 machining. Originality/value – The Jatropha (vegetable) oil, in relation to its physicochemical properties, appeared to be the best one fit for being used in the machining of aluminum alloys 7050-T7451 because it did not interfere with any of the elements involved in the formation of intergranular corrosion and/or pitting, which are not allowed in the aeronautical production of parts. Jatropha (vegetable) cutting oil, besides being produced from a clean and renewable source, has the inherent characteristics that can help attain a sustainable manufacturing.
15
Nelson, Wendy R., Barry B. Hanan, David W. Graham, Steven B. Shirey, Gezahegn Yirgu, Dereje Ayalew, and Tanya Furman. "Distinguishing Plume and Metasomatized Lithospheric Mantle Contributions to Post-Flood Basalt Volcanism on the Southeastern Ethiopian Plateau." Journal of Petrology 60, no. 5 (May 1, 2019): 1063–94. http://dx.doi.org/10.1093/petrology/egz024.
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Abstract Magmatism in the East African Rift System (EARS) contains a spatial and temporal record of changing contributions from the Afar mantle plume, anciently metasomatized lithosphere, the upper mantle and the continental crust. A full understanding of this record requires characterizing volcanic products both within the rift valley and on its flanks. In this study, three suites of mafic, transitional to alkaline lavas, were collected over a northeast-southwest distance of ∼150 km along the southeastern Ethiopian Plateau, adjacent to the Main Ethiopian Rift. Specifically, late Oligocene to Quaternary mafic lavas were collected from Chiro, Debre Sahil and the Bale Mountains. New major element, trace element, 40Ar/39Ar ages and isotopic results (Sr, Nd, Pb, Hf, Os, He) show spatial and temporal variation in the lavas caused by dynamical changes in the source of volcanism during the evolution of the EARS. The trace element compositions of Oligocene and Miocene Chiro lavas indicate derivation from mildly depleted and nominally anhydrous lithospheric mantle, with variable inputs from the crust. Further south, Miocene Debre Sahil and alkaline Bale Mountains lavas have enriched incompatible trace element ratios (e.g. Ba/Nb = 12–43, La/SmN = 3·1–4·9, Tb/YbN = 1·6–2·4). Additionally, their 87Sr/86Sr, 143Nd/144Nd, 176Hf/177Hf and 206Pb/204Pb values trend toward a radiogenic Pb (HIMU) component. Radiogenic 187Os/188Os in these lavas correlates positively with 206Pb/204Pb and trace element indicators consistent with ancient metasomatic enrichment of their mantle source. In contrast, transitional Miocene Bale Mountains lavas have lower incompatible trace element abundances, less enriched trace element ratios (Ba/Nb ∼7, La/SmN = 2·3–2·5) and less radiogenic isotopic signatures that originate from melting garnet-bearing, anhydrous lithospheric mantle (Tb/YbN = 2·5–2·9). Pliocene and Quaternary Bale Mountains basaltic lavas are chemically and isotopically similar to Main Ethiopian Rift lavas. Trace element and isotopic indicators in both of these suites denote an amphibole-bearing source distinct from that sampled by the older Bale Mountains lavas. Isotopically, Pliocene and Quaternary Bale lavas have notably less radiogenic Sr–Nd–Pb–Hf isotopic ratios. Quaternary Bale Mountains lavas have the strongest mantle plume contribution (3He/4He = 12·1–12·5 RA), while other Bale Mountains, Debre Sahil and Chiro lavas were derived dominantly by melting of lithospheric or upper mantle sources (3He/4He = 5·1–9·1 RA). A multi-stage, regional-scale model of metasomatism and partial melting accounts for the spatial and temporal variations on the southeastern Ethiopian Plateau. Early Debre Sahil and alkaline Bale Mountains mafic lavas are melts derived from Pan-African lithosphere containing amphibole-bearing metasomes, while later transitional Bale basalts are melts of lithosphere containing anhydrous, clinopyroxene-rich veins. These ancient metasomatized domains were eventually removed through preferential melting, potentially during thermal erosion of the lithosphere or lithospheric foundering. Pliocene and Quaternary Bale Mountains lavas erupted after tectonic extension progressed throughout Ethiopia and was accompanied by increased plume influence on the volcanic products.
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Jayaganth, A., A. Deepak Mani, and K. Jayakumar. "Experimental Study on Effect of Machining Parameters and Environment on Drilling Characteristics of Stainless Steel 304." Applied Mechanics and Materials 852 (September 2016): 273–78. http://dx.doi.org/10.4028/www.scientific.net/amm.852.273.
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Stainless Steel 304 (SS304) is a non magnetic material and has excellent corrosion resistance and forming characteristics which is mainly used in chemical, petrochemical, aerospace industries, etc. Few examples are kitchen wares, cryogenic vessels, surgical equipments and heat exchangers. However, most of these components require different machining processes to produce the desired product or assembly. But, during machining of SS 304, industries are facing major difficulties such as high tool wear and poor surface finish due to low thermal conductivity and high built up edge (BUE) tendency. Many researchers started working towards machinability of SS304 in different machining processes. Among these, few works have been started on drilling of this material. Drilling process is mainly used for assembly of structural parts and also used as primary process for boring, reaming, etc. By considering the above applications and challenges in machining of this material, the present study analyzes the effect of cutting speed, feed and machining environment on surface roughness and machining time during drilling process.Drilling experiments have been conducted in a jig boring machine using 10 mm diameter HSS twist drill bit by varying cutting speed (16, 22 and 28 m/min), feed (0.08, 0.12 and 0.16 mm/rev) and machining environment (dry, normal soluble oil flood coolant and kerosene) as per Taguchi’s L9 orthogonal array. The results indicated that, average surface roughness (Ra) increased from 2.088 μm to 6.647 μm when increase in cutting speed and feed. Roughness value decreased for kerosene environment compare to dry and coolant environment. Also, machining time decreased from 15.01 second to 5.58 second when increase in cutting speed and feed along with kerosene environment compared to dry and flood coolant condition.
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Orekhov, R. A. "KING PEPI’S ROLE IN FORMING MEMPHIS, THE FUTURE CAPITAL OF EGYPT." Journal of the Institute of Oriental Studies RAS, no. 3 (13) (2020): 40–56. http://dx.doi.org/10.31696/2618-7302-2020-3-40-56.
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There is a common point of view in Egyptology that Memphis was a state capital since the earliest times and that its protecting gods were Ptah and his spouse Sekhmet. Arguing this concept, the author tries to find the reason why a pyramid city of Pepi I — Mennefer — became a core of the future capital. The main conclusion is following: Constructing his pyramid complex, Pepi I probably included into it a cult center of Habes where Bastet and Imhotep, a high priest of Ra, were worshiped. Imhotep, a companion of the king Djoser, was known as a priest and charmer who tamed the fiery forces of Sirius associated with Bastet, after which the great drought was over. To commemorate this, New Year celebration and the first sun calendar were established. Imhotep’s tomb became an important cult place, where ceremonies important for surviving of the Egyptian state were conducted. In the second half of the Old Kingdom period the Nile started to flood much less, which led to the decline of agriculture. Thus, the role of the cult center of Habes and Imhotep grew greatly. By including Habes, Pepi protected the dominion of his pyramid city from negative influence of Bastet and decreased flooding. The fact that Mennefer was a successor of the aforementioned cult center determined its capital functions in future.
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Eltaggaz, Abdelkrem, Ibrahim Nouzil, and Ibrahim Deiab. "Machining Ti-6Al-4V Alloy Using Nano-Cutting Fluids: Investigation and Analysis." Journal of Manufacturing and Materials Processing 5, no. 2 (April 27, 2021): 42. http://dx.doi.org/10.3390/jmmp5020042.
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Minimum Quantity Lubrication nanofluid (MQL-nanofluid) is a viable sustainable alternative to conventional flood cooling and provides very good cooling and lubrication in the machining of difficult to cut materials such as titanium and Inconel. The cutting action provides very difficult conditions for the coolant to access the cutting zone and the level of difficulty increases with higher cutting speeds. Furthermore, high compressive stresses, strain hardening and high chemical activity results in the formation of a ‘seizure zone’ at the tool-chip interface. In this work, the impact of MQL-nanofluid at the seizure zone and the corresponding effects on tool wear, surface finish, and power consumption during machining of Ti-6Al-4V was investigated. Aluminum Oxide (Al2O3) nanoparticles were selected to use as nano-additives at different weight fraction concentrations (0, 2, and 4 wt.%). It was observed that under pure MQL strategy there was significant material adhesion on the rake face of the tool while the adhesion was reduced in the presence of MQL-nanofluid at the tool-chip interface, thus indicating a reduction in the tool chip contact length (TCCL) and reduced seizure effect. Furthermore, the flank wear varied from 0.162 to 0.561 mm and the average surface roughness (Ra) varied from 0.512 to 2.81 µm. The results indicate that the nanoparticle concentration and the reduction in the seizure zone positively influence the tool life and quality of surface finish.
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Pandey, A., R. Kumar, A. K. Sahoo, A. Paul, and A. Panda. "Performance Analysis of Trihexyltetradecylphosphonium Chloride Ionic Fluid under MQL Condition in Hard turning." International Journal of Automotive and Mechanical Engineering 17, no. 1 (March 27, 2020): 7629–47. http://dx.doi.org/10.15282/ijame.17.1.2020.12.0567.
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The current research presents an overall performance-based analysis of Trihexyltetradecylphosphonium Chloride [[CH3(CH2)5]P(Cl)(CH2)13CH3] ionic fluid mixed with organic coconut oil (OCO) during turning of hardened D2 steel. The application of cutting fluid on the cutting interface was performed through Minimum Quantity Lubrication (MQL) approach keeping an eye on the detrimental consequences of conventional flood cooling. PVD coated (TiN/TiCN/TiN) cermet tool was employed in the current experimental work. Taguchi’s L9 orthogonal array and TOPSIS are executed to analysis the influences, significance and optimum parameter settings for predefined process parameters. The prime objective of the current work is to analyze the influence of OCO based Trihexyltetradecylphosphonium Chloride ionic fluid on flank wear, surface roughness, material removal rate, and chip morphology. Better quality of finish (Ra = 0.2 to 1.82 µm) was found with 1% weight fraction but it is not sufficient to control the wear growth. Abrasion, chipping, groove wear, and catastrophic tool tip breakage are recognized as foremost tool failure mechanisms. The significance of responses have been studied with the help of probability plots, main effect plots, contour plots, and surface plots and the correlation between the input and output parameters have been analyzed using regression model. Feed rate and depth of cut are equally influenced (48.98%) the surface finish while cutting speed attributed the strongest influence (90.1%). The material removal rate is strongly prejudiced by cutting speed (69.39 %) followed by feed rate (28.94%) whereas chip reduction coefficient is strongly influenced through the depth of cut (63.4%) succeeded by feed (28.8%). TOPSIS significantly optimized the responses with 67.1 % gain in closeness coefficient.
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TRAN, Huynh Bao Chau, and Fumikazu UBUKATA. "Understanding local and scientific knowledge about flooding adaptations in low-lying areas of Central Vietnam." Journal of Vietnamese Environment 12, no. 2 (November 12, 2020): 123–31. http://dx.doi.org/10.13141/jve.vol12.no2.pp123-131.
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This research focuses on clarifying the local and scientific knowledge about flooding adaptations, the interaction between local knowledge and scientific information in the low-lying area of Central Vietnam is analyzed. Data was obtained using three techniques including: semi-structured interviews, direct observation and household surveys. Responses indicate that the villagers have accumulated and inherited this type of knowledge in their society for a long time. The level of local knowledge is affected by gender, occupation and house location. This implies that the villagers’ social roles and their everyday interactions with the natural environment have nurtured an accumulated local knowledge. Scientific information is provided by the National Committee for Flood and Storm Control and National Center for Hydrometeorology Prediction. It contains information regarding disaster type, intensity, risk level and directions. The information is transferred to local people through mass media, social networks and official documents. However, local people are credulous toward scientific information given by the state. It was found that many villagers are not likely to follow the official guideline, especially the villagers with a high level of local knowledge.
Nghiên cứu tập trung làm rõ kiến thức bản địa và khoa học về thích ứng lũ lụt cũng như mối tương tác của chúng ở vùng trũng thấp miền Trung Việt Nam. Dữ liệu được thu thập bằng cách sử dụng kết hợp ba phương pháp bao gồm phỏng vấn bán cấu trúc, quan sát trực tiếp và khảo sát hộ gia đình. Các kết quả nghiên cứu chỉ ra rằng người dân đã tích lũy và kế thừa kiến thức bản địa từ xã hội của họ trong một thời gian dài. Mức độ kiến thức bản địa bị ảnh hưởng bởi giới tính, nghề nghiệp và vị trí nhà ở. Vai trò xã hội và những tương tác hàng ngày của người dân với môi trường tự nhiên đã nuôi dưỡng và tích lũy kiến thức bản địa. Thông tin khoa học được cung cấp bởi Ủy ban Phòng chống lụt bão Quốc gia và Trung tâm Dự báo Khí tượng Thủy văn Quốc gia. Các thông tin về loại thiên tai, cường độ, mức độ rủi ro và hướng chỉ dẫn được thông báo. Thông tin này được chuyển đến người dân thông qua các phương tiện thông tin đại chúng, mạng xã hội và các văn bản chính thức. Tuy nhiên, người dân địa phương chủ quan trước những thông tin khoa học do cơ quan nhà nước đưa ra. Nhiều người dân không tuân theo các hướng dẫn chính thức của chính quyền địa phương, đặc biệt là những người có mức độ kiến thức bản địa được đánh giá cao.
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Yim, D. Y., and S. W. Kim. "Optimum Sampling Interval for Ra Roughness Measurement." Proceedings of the Institution of Mechanical Engineers, Part C: Mechanical Engineering Science 205, no. 2 (March 1991): 139–42. http://dx.doi.org/10.1243/pime_proc_1991_205_101_02.
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This paper describes the statistical treatment of determining the sampling interval for the digital Ra roughness measurement. It is proved that the optimum sampling interval can be determined from the Rq/Ra ratio of the surface to be measured and the evaluation length. A nomograph is suggested for practical uses on the workshop floor.
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Beznosikov, V. A., and Evgeny D. Lodygin. "GEOCHEMICAL ASSESSMENT OF ECOLOGICAL STATE OF SOILS." Hygiene and sanitation 97, no. 7 (July 15, 2018): 623–28. http://dx.doi.org/10.18821/0016-9900-2018-97-7-623-628.
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There was executed the ecological and geochemical assessment of the regional background of heavy metals (HM) and hydrocarbons in the soils of the Komi Republic. There were examined 249 soil samples taken from 15 organic horizons of the main types and subtypes of background soils from Usinsk and Pechora districts of the Komi Republic. The quantitative chemical analysis of HM in the soil samples was carried out by atomic absorption method: Cu, Pb, Zn, Cd, Ni, Mn - on atomic emission spectrometer Spectro Ciros inductively coupled argon plasma, Hg - using the RA-915+ mercury spectrometer on the pyrolytic prefix RP-91C. The concentration of hydrocarbons in the soil samples was determined by the value of the hexane extract of the fluorescence intensity measured on a liquid analyzer Fluorat-02. Background levels of HM and in the soils were found to be determined by characteristics of the particle size distribution of soil-forming rocks, as well as the arrangement of soil geochemical autonomous and subordinate landscapes. The basic amount of HM and hydrocarbons accumulated in the organic horizons: the largest, as a rule, in the soils of river valleys (flood), on flat depressions, poorly drained river ridges and gentle slopes (bog-podzolic and illuvial-ferruginous); the lowest - in the watersheds (podzols). Differentiation between HM and hydrocarbons in genetic horizons is more pronounced in loamy automorphic and less sandy, semi-hydromorphic and hydromorphic soils. For all soils, there is the typical eluvial-illuvial distribution of HM and hydrocarbons in the profile. The revealed pair correlations between the individual elements in the soils give an indication of the similar orientation of biogeochemical processes in the soil formation. The database of the content of HM and hydrocarbons in soils using GIS technology was created. The research results were the basis for the Order of the Ministry of Natural Resources and Environmental Protection of the Komi Republic of November 25, 2009 N 529 «On establishing norms background concentrations of chemical elements and hydrocarbons in the soils of the Komi Republic».
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Luk, Jim T. C., Freeman K. C. Kwok, Indy M. K. Ho, and Del P. Wong. "Acute Responses of Core Muscle Activity during Bridge Exercises on the Floor vs. the Suspension System." International Journal of Environmental Research and Public Health 18, no. 11 (May 31, 2021): 5908. http://dx.doi.org/10.3390/ijerph18115908.
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This study aimed to compare the neuromuscular activation of selected core musculature in supine and prone bridge exercises under stable versus suspended conditions. Forty-three healthy male participants were recruited to measure the electromyographic activities of the rectus abdominis (RA), lumbar multifidus (LM), thoracic erector spinae (TES), rectus femoris (RF), gluteus maximus (GM), and biceps femoris (BF) during supine and prone bridge exercises under six conditions: control, both arms and feet on the floor (Pronecon and Supinecon); arms on the floor and feet on the suspension system (Prone-Feetsuspension and Supine-Feetsuspension); and arms on the suspension system and feet on the floor (Prone-Armsuspension and Supine-Armsuspension). Prone-Armsuspension yielded significantly higher activities in the RA, RF, TES, and LM than Prone-Feetsuspension (p < 0.01) and Pronecon (p < 0.001). Moreover, Supine-Feetsuspension elicited significantly higher activities in the RA, RF, TES, LM, and BF than Supine-Armsuspension (p < 0.01) and Supinecon (p < 0.001). Furthermore, Supine-Feetsuspension elicited significantly higher activities in the RF, TES, and BF than Supinecon (p < 0.01). Therefore, if the RA and/or RF were the target training muscles, then Prone-Armsuspension was recommended. However, if the TES, LM, and/or BF were the target training muscles, then Supine-Feetsuspension was recommended.
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Kuznetsov, V. K., N. N. Isamov, and A. V. Panov. "Assessment of grasslands remediation effectiveness in different periods after the Chernobyl accident." "Radiation and Risk" Bulletin of the National Radiation and Epidemiological Registry 30, no. 2 (2021): 50–61. http://dx.doi.org/10.21870/0131-3878-2021-30-2-50-61.
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The paper presents the impact of remedial actions on 137Cs content in agricultural lands affected by radiation as a result of the Chernobyl accident. The remediation of Cs-137 – contaminated of hayfields and pastures in the vicinity of the Veprin village, located in the Bryansk region, was car-ried out in 2004. Remediation of greenlands aimed at reduction of soil-forage-milk transfer of 137Cs involved deep ploughing of the soil, liming, introducing high doses of mineral fertilizers and sowing grass mixtures. Evaluation of remedial actions effectiveness after the first three years and 15 years later is discussed in the paper. Undertaken agrotechnical measures resulted in reduc-tion of soil surface layer density contamination with 137Cs by 1.8 times. Due to remediation of the pasture in the river flood-plain the soil surface layer density contamination with 137Cs was re-duced by 2.7 times and dose rate by 1.9 times. It is to be noted that lower geomorphological ele-ments of the landscape with prevailing peat soils are critical for accumulation of 137Cs in the grass stand and accumulation of radionuclides in the river floodplain. In the first three years after the remediation 137 Cs soil-grass transfer was reduced by 3 times, and in cultivated hayfield soils the 137Cs transfer was reduced by 8 times. While the land reclamation effectiveness weakened signif-icantly in 15 years after the remediation, accumulation of 137Cs in grass stand grown on cultivated hayfields was 1.6 time lower than in the grass grown in uncultivated lands. The radionuclide con-tent in cultivated pastures is 1.8 times lower than in uncultivated ones. The content of 137Cs in milk was reduced by 3.3 times in the first years after grasslands reclamation, in 15 years the reduction factor was 1.5. Outcomes of long-term follow-up of radioecological situation in grasslands, af-fected by radiation as a result of the Chernobyl accident, following land remediation and the as-sessment of its effectiveness can be used as the motivation for and benefits of remedial actions ensuring radiation safety of agricultural products from radioactively contaminated areas. The ob-tained results can be used for clarification and adjustment of the strategies of reclamation of ra-dioactively contaminated lands and optimal use of grasslands after their restoration.
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Maden, Malcolm, and Nigel Holder. "The involvement of retinoic acid in the development of the vertebrate central nervous system." Development 113, Supplement_2 (April 1, 1991): 87–94. http://dx.doi.org/10.1242/dev.113.supplement_2.87.
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We discuss here both previously published data and our current experiments which suggest that the vitamin A derivative, retinoic acid (RA), may play a role in the development of the vertebrate central nervous system (CNS). This evidence comes from the following: both an excess and a deficiency of vitamin A causes embryonic defects of the CNS; RA has been detected endogenously in the CNS; RA stimulates neurite outgrowth; the retinoic acid receptors have been detected with interesting distributions in the CNS; the binding protein for retinol, namely cellular retinol binding protein (CRBP) is found in the radial glia of the ventral floor plate; the binding protein for RA, namely, cellular retinoic acid binding protein (CRABP) is found in particular sets of axons in the developing spinal cord, in particular rhombomeres in the developing hindbrain and in the neural crest. Some hypotheses for the possible role of RA in various aspects of CNS development are discussed.
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Knoepp, Jennifer D., Katherine J. Elliott, Barton D. Clinton, and James M. Vose. "Effects of prescribed fire in mixed oak forests of the southern Appalachians: forest floor, soil, and soil solution nitrogen responses." Journal of the Torrey Botanical Society 136, no. 3 (July 2009): 380–91. http://dx.doi.org/10.3159/08-ra-052.1.
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Tran, T. V., and N. T. Thuy. "Some characteristics of the resultant air flow from motions induced by ventilation and heat source in a two-dimensional enclosure." Vietnam Journal of Mechanics 37, no. 3 (August 25, 2015): 177–86. http://dx.doi.org/10.15625/0866-7136/37/3/5837.
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Ventilated air flow in an enclosure is often unsteady (turbulent) at even very low Reynolds number (Re). Meantime natural convection in a box is stationary motion at large enough Rayleigh number (Ra). This paper deals with the interaction between two those flows in a two-dimensional room. The room has one inlet and one or two outlets. A heat source locates on the floor. The numerical simulation of the interaction is carried out at some values of Re and Ra for two cases of the inlet and outlet configuration. Some interesting characteristics of the resultant flow are discovered. The heat amount released by the source and removed from the room by different types of this flow is also provided.
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Peng, Gunnar G., and John R. Lister. "The initial transient and approach to self-similarity of a very viscous buoyant thermal." Journal of Fluid Mechanics 744 (March 12, 2014): 352–75. http://dx.doi.org/10.1017/jfm.2014.75.
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AbstractAn isolated buoyant thermal in very viscous fluid has been shown to attain a self-similar form at large times which grows as $t^{1/2}$ (Whittaker & Lister J. Fluid Mech., vol. 606, 2008, pp. 295–324). For large values of the Rayleigh number $\mathit{Ra}$ (based on the conserved total buoyancy), the similarity solution is slender with a roughly spherical head at the top and a long tail that contains most of the buoyancy and extends down to the origin. We investigate the time-dependent behaviour of the thermal numerically; both the long-time behaviour in terms of perturbations to the similarity solution and the short-time evolution from a spherical initial condition. Using a spectral method, we find the growth rates of the linear perturbations and their spatial structure in similarity space. All eigenmodes decay monotonically for $\mathit{Ra}\lesssim 360$, while for larger $\mathit{Ra}$ the dominant (slowest decaying or fastest growing) eigenmodes are oscillatory with waves propagating up the tail. Above a critical value $\mathit{Ra}_c \approx 10\, 000$, the steady solution becomes unstable to a limit cycle. A one-dimensional reduction to horizontally integrated quantities hints at a theoretical explanation for the oscillatory behaviour, but does not reproduce the loss of stability. Investigation of the initial transient at large $\mathit{Ra}$ reveals that an initially spherical thermal can rise $O(100)$ times its initial diameter before approaching its final self-similar shape. The presence of a rigid horizontal floor below the thermal makes a quantitative difference of around 10 % to the rate of rise at large $\mathit{Ra}$.
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Lot, Ana Virgínia, Ana Paula Margarido Menegazzo, Camila Tavares Brasileiro, Fábio Gomes Melchiades, and Anselmo Ortega Boschi. "Correlations between the slip resistance and surface roughness of ceramic floor tiles." Research, Society and Development 10, no. 4 (March 30, 2021): e4410413865. http://dx.doi.org/10.33448/rsd-v10i4.13865.
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The characteristics of the floor surface profile are one of the factors that can be responsible for slip and fall accidents. To reduce the incidence of these accidents, it is essential to identify the profile features necessary for floor covering materials to be suitable for slipping risk areas. The objective of the present work was to investigate correlations between the slip resistance and the surface roughness of ceramic floor tiles. The slip resistance and the surface roughness of commercial ceramic tiles, with a diversity of surface finishes, were characterized by the pendulum method and contact profilometry, respectively. It was concluded that the presence of a large number of sharp peaks per unit of length of the profile is required for high slip resistance ceramic tiles. It was also found that the presence of waviness contributes to increasing the floors slip resistance even more. Through regression analysis, a good correlation between the pendulum results and the roughness parameter Ra was found.
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Westin, U., M. Nyström, I. Ljungcrantz, B. Eriksson, and K. Ohlsson. "The presence of elafin, SLPI, IL1-RA and STNFα RI in head and neck squamous cell carcinomas and their relation to the degree of tumour differentiation." Mediators of Inflammation 11, no. 1 (2002): 7–12. http://dx.doi.org/10.1080/09629350210304.
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Biopsy samples of head and neck carcinomas were investigated with regard to elafin, secretory leukocyte protease inhibitor (SLPI), interleukin 1-receptor antagonist [(IL)1-RA] and soluble tumour necrosis factor α receptor antagonist (STNFα RI). SLPI and elafin are serine protease inhibitors produced in the serous cells of the upper respiratory airways and in the keratinocytes, respectively. We have now found the presence of elafin and SLPI in squamous cell carcinomas of the upper respiratory tract (tonsillar, hypopharyngeal, tongue, mouth floor, gingival and laryngeal cancer). Significantly higher amounts of SLPI and elafin are present in well-differentiated and moderately differentiated tumours than in poorly differentiated tumours (p<0.0001andp<0.0015). Tumour necrosis factor-α and IL-1β have been shown to stimulate the production of SLPI and elafin. Since these cytokines can both be difficult to detect, we chose to study their inhibitors, STNF α RI and IL1-RA, instead. IL1-RA was expressed in highly differentiated tumours as well as in poorly differentiated ones. No significant difference was seen between the groups. STNF α RI was only found in very small amounts, sparsely distributed in the tumours, and was not related to the degree of differentiation.
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Quiroz Sandoval, Gonzalo Alfonso, Nathalie Tabilo, Cristóbal Bahamondes, and Pilar Bralic. "Surface electromyography comparison of the abdominal hypopressive gymnastics against the prone bridge exercise." Revista Andaluza de Medicina del Deporte 12, no. 3 (March 26, 2019): 243–46. http://dx.doi.org/10.33155/j.ramd.2019.03.010.
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Objectives: Abdominal hypopressive gymnastics (AHG) is a little-researched method designed to train the muscles of the abdominal wall and pelvic floor under low stress. This study’s objective is to compare levels of muscle activation in AHG against prone bridge by surface electromyography (sEMG) of the abdominal wall muscles.
Methods: Twenty healthy subjects were enrolled to measure the muscle activity of the rectus abdominis (RA), transversus abdominis/internal oblique (Tra/IO), and external oblique (EO) during three exercises: prone bridge (PB), orthostatic hypopressive (OH), and hypopressive bridge (HB). Root mean square values normalized to the PB (%PB) as a baseline were used to compare the PB against OH and HB.
Results: The median PB ratio (%PB) for the Tra/IO showed –10.31% and +59.7% activation during OH and the HB, respectively, whereas the RA showed –77.8% and +19.3% and the EO –39.8% and +9.8%. Significant differences were found for all muscles except the Tra/IO during the OH.
Conclusion: This study’s results suggest that hypopressive exercises facilitate the activation of the Tra/IO similar to bridge exercises while simultaneously reducing RA and EO activity. This suggests that hypopressive training is a valid alternative for activating the abdominal muscles, isolating the Tra/IO at low intra-abdominal pressure.
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Situmorang, Helfrida. "Pengalaman Perawat dalam Menerapkan Manajemen Pengendalian Infeksi di RSUP H. Adam Malik Medan." Jurnal Persatuan Perawat Nasional Indonesia (JPPNI) 3, no. 1 (August 31, 2018): 24. http://dx.doi.org/10.32419/jppni.v3i1.99.
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AbstrakPencegahan dan Pengendalian Infeksi (PPI) rumah sakit adalah kegiatan yang meliputi perencanaan, pelaksanaan dan pengawasan serta pembinaan dalam upaya menurunkan angka kejadian Infeksi Rumah Sakit (IRS) pada pasien atau petugas rumah sakit dan mengamankan lingkungan rumah sakit dari risiko transmisi infeksi yang dilaksanakan melalui manajemen risiko, tata laksana klinik yang baik dan pelaksanaan Kesehatan dan Keselamatan Kerja Rumah Sakit. Tujuan penelitian: mengeksplorasi pengalaman perawat dalam menerapkan manajemen pengendalian infeksi di RSUP H. Adam Malik Medan. Metode: Jenis penelitian ini merupakan studi kualitatif dengan desain fenomenologi deskriptif. Partisipan dalam penelitian ini adalah IPCLN (Infection Prevention Control Link Nurse) yaitu perawat penghubung pengendali infeksi, ditentukan dengan teknik Purposive Sampling. Pengumpulan data menggunakan metode wawancara secara mendalam terhadap 12 perawat IPCLN yang terdiri dari IPCLN yang bertugas di ruang rawat inap yang berisiko terjadi infeksi seperti ruang Neurologi (RA 4), RB 1 Obgyn, RA 2, CVCU, RB 4 Anak, R. Inap Kardio Vaskuler Lantai 4, RB 3, VIP B, RB 2 A, R. Inap Kardio Vaskuler Lantai 3, RA 3 THT, ICU Anak, di RSUP. H. Adam Malik Medan. Analisis data dilakukan setelah proses pengumpulan data pada bulan Juli 2016 dengan menggunakan tehnik analisis Colaizzi. Hasil: Hasil penelitian ini menemukan dua tema yaitu melakukan pengawasan yang ketat dan mendapatkan hambatan dalam melaksanakan pengendalian infeksi. Kesimpulan: Pengawasan terkait pengendalian infeksi sudah dilaksanakan dengan baik setiap hari dan setiap ada pasien baru. Hambatan yang didapat seperti beberapa petugas yang kurang patuh untuk menggunakan APD (Alat Pelindung Diri) dan melaksanakan cuci tangan.Kata kunci: Pengendalian infeksi, manajemen, perawatNURSE’S EXPERIENCE IN APPLYING INFECTION CONTROL MANAGEMENT AT H. ADAM MALIK HOSPITAL OF MEDANAbstractInfection Prevention and Control at hospitals are activities that include planning, implementation and supervision as well as development in order to reduce the incidence of Hospital-acquired infection in patients or hospital personnel and to secure hospital environment from the risk of transmission of infection. It is carried out through management risk, good clinical management and implementation of Hospital Occupational Health and Safety. Objective: To explore the experience of nurses in implementing infection control management at H. Adam Malik Hospital of Medan. Methods: This research is qualitative with descriptive phenomenological design. Participants in this study were the Infection Prevention Control Link Nurses (IPCLNs), whom were taken using purposive sampling technique. Data were collected using in-depth interviews to 12 IPCLNs consisting of IPCLNs who served in the inpatient unit facing the risk of infection such as Neurology room (RA 4), RB 1 Obgyn, RA 2, CVCU, RB 4 for children, Cardio vascular Inpatient room 4th Floor, RB 3, VIP B, RB 2 A, Cardio vascular Inpatient room 3rd Floor, RA 3 ENT, ICU for Children at H. Adam Malik Hospital of Medan. Data were analyzed after the data were collected in July 2016 using the Colaizzi’s method of data analysis. Results: The results of this study found two themes, namely strict supervision and obstacles in controlling infection. Conclusion: Supervision related to infection control has been carried out well every day and when a new patient is admitted. Obstacles include some officers who are less obedient to use PPE (Personal Protective Equipment) and to wash hand.Keywords: Infection control, management, nurses
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Mulligan, K., S. Hirani, S. Clarke, N. Evans, C. Flood, J. Taylor, L. Wedderburn, and S. Newman. "PARE0018 WEBSITE FOR PARENTS OF CHILDREN WITH JUVENILE IDIOPATHIC ARTHRITIS REDUCES PARENTING STRESS." Annals of the Rheumatic Diseases 79, Suppl 1 (June 2020): 1295.2–1295. http://dx.doi.org/10.1136/annrheumdis-2020-eular.3510.
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Background:Having a child with JIA presents many challenges. Many parents experience considerable stress. Parental distress and functioning have been found to be related to child outcomes (Cousino, 2013), therefore interventions that help parents to manage their child’s illness are important for both parents and child. We developed a website for parents of children with newly diagnosed JIA to help increase parental confidence in managing their child’s arthritis and reduce parenting stress.Objectives:To evaluate the efficacy of a web-based tool ‘WebParC’ for parents of children with JIA.Methods:Design:Multi-centre randomised controlled trial conducted in 16 tertiary paediatric rheumatology centres in England.Participants:Parent(s) of children aged ≤12 years, diagnosed with JIA within the previous six months.Procedures:Parents were enrolled when they attended the rheumatology service and were randomised by household to either the intervention arm (I) who were given access to the website in addition to their child’s standard care or the control arm (C) who received standard care alone.The primary outcome was parenting stress, measured with the Pediatric Inventory for Parents (PIP) (Streisand, 2001), which parents completed prior to randomisation and at 4-months and 12-months post randomisation.Website content was developed by a multidisciplinary team including rheumatology, physiotherapy, ophthalmology, social work, podiatry, occupational therapy, clinical and health psychology along with parents of children with JIA. It includes information about JIA and its treatment plus a ‘toolkit’ for parents. The toolkit is based on cognitive-behavioural principles to develop skills for managing JIA-related issues.Analysis:We conducted linear mixed models to examine the main effect of trial arm (I vs C), main effect of time (between 4M and 12M scores), and interaction between trial arm and time on PIP scores, after controlling for baseline scores.Results:A total of 220 parents (183 mothers, 37 fathers) of 203 children were randomised, 106 intervention and 114 controls. Parents mean (SD) age was 36.5 (6.5). Their children with JIA were mostly female (137/203, 67.5%), mean (SD) age of 6.1 (3.4) years. There were 107 (52.7%) with oligoarthritis, 65 (32%) polyarthritis, 8 (3.9%) systemic and 23 (11.3%) other JIA subtypes. Seventy (34.5%) were prescribed methotrexate.Trial arms did not differ significantly at baseline except for parent education, which was higher in the intervention group and was controlled for in the analysis.Follow-up assessments were completed by 133 (I60, C73) at 4M and 124 (I58, C66) at 12M.We found significant main effects of trial arm on PIP Difficulty (p=0.022, Control (Mean=93.62, SE=2.717) > Intervention (Mean=84.23, SE=3.025)) and PIP Frequency (p= 0.008, Control (Mean=95.78, SE=2.400) > Intervention (Mean=86.23, SE=2.622), with Controls reporting significantly greater frequency and difficulty of stressful events than the Intervention group (Fig 1).Conclusion:This trial found that a website for parents of children with JIA can help to reduce parenting stress.References:[1]Cousino MK, Hazen RA. J Pediatr Psychol 2013; 38(8):809-28[2]Streisand R, Braniecki S, Tercyak KP, Kazak AE. J Pediatr Psychol 2001; 26(3):155-62.Acknowledgments:We thank all parent participants, the health professionals and parents who developed website content and the clinical teams who supported recruitment.Funded by NIHR RfPB.Disclosure of Interests:Kathleen Mulligan: None declared, Shashivadan Hirani: None declared, Sally Clarke: None declared, Neil Evans: None declared, Chris Flood: None declared, Jo Taylor: None declared, Lucy Wedderburn Speakers bureau: Pfizer, Stanton Newman Grant/research support from: Yes Baxter Healthcare Educational Grants not in relation to rheumatology, Speakers bureau: Yes Baxter Healthcare and Merke Sharp and Dome
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Abuín-Porras, Vanesa, Mónica de la Cueva-Reguera, Pedro Benavides-Morales, Rocío Ávila-Pérez, Blanca de la Cruz-Torres, Helios Pareja-Galeano, María Blanco-Morales, and Carlos Romero-Morales. "Comparison of the Abdominal Wall Muscle Thickness in Female Rugby Players Versus Non-Athletic Women: A Cross-Sectional Study." Medicina 56, no. 1 (December 25, 2019): 8. http://dx.doi.org/10.3390/medicina56010008.
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Background and Objectives: Rugby players engage in demanding, high loading muscular activity in the spine. Study of the abdominal wall architecture in female rugby athletes is relevant to the possible muscular asymmetry secondary to sport practice and the relationship between the abdominal wall and the pelvic floor muscles. Activation of the transversus abdominis (TrAb) generates an increase in the bladder neck muscle. Moreover, an increased interrecti distance (IRD) is related to urinary incontinence and has a higher prevalence in athletic women. The aim of the present study was to compare and quantify, with ultrasound imaging (USI), the thickness of the transversus abdominis (TrAb), external oblique (EO), internal oblique (IO), rectus abdominis (RA), and interrecti distance (IRD) in female rugby players versus non-athletic women in order to improve upon existing knowledge about abdominal wall configuration in female athletes. Materials and Methods: A sample of 32 women was recruited at the Universidad Europea Research Lab and divided in two groups: a rugby group (n = 16) and a non-athletic women group (n = 16). The thickness of the TrAb, EO, IO, RA, and IRD were assessed by USI in both groups. Results: There were statistically significant differences for the ultrasound evaluation thickness of the right TrAb (p = 0.011; d = 0.10), EO (p = 0.045; d = 0.74), IO (p = 0.003; d = 1.32), and RA (p = 0.001; d = 1.38) showing a thickness increase for the rugby group with respect to the control group. For the IRD thickness, there were no significant differences (p > 0.05) between groups. Conclusions: An increased TrAb, IO, EO, and RA thickness may be shown in female rugby players versus non-athletic women. Nevertheless, statistically relevant differences were not found for the IRD between both groups.
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Abouricha, Noureddine, Mustapha El Alami, and Khalid Souhar. "Lattice Boltzmann modeling of convective flows in a large-scale cavity heated from below by two imposed temperature profiles." International Journal of Numerical Methods for Heat & Fluid Flow 30, no. 5 (July 17, 2019): 2759–79. http://dx.doi.org/10.1108/hff-12-2018-0823.
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Purpose The purpose of this paper is to model the convective flows in a room equipped by a glass door and a heated floor of length l = 0.8 × H and submitted to a sinusoidal temperature profile and mono alternative temperature profile. Design/methodology/approach The paper opts for a numerical study of convective flows in a large scale cavity using the Lattice Boltzmann Method (LBM) by considering a two dimensions (2D) square cavity of side H and filled by air (Pr = 0.71). All the vertical walls, the ceiling and the rest of the floor are thermally insulated, the hot portion of length l = 0.8×H is heated with two imposed temperature profiles of amplitude values 0.2 ≤ a ≤ 0.6 and for two different periods ζ = ζ0 and ζ = 0.4×ζ0. One of the vertical walls has a cold portion θc = 0 that represents the glass door. Findings A systematic study of the flow structure and heat transfer is carried out considering principal control parameters: amplitude “a” and period ζ for Rayleigh number Ra = 108. Effects of these parameters on results are presented in terms of isotherms, streamlines, profiles of velocities, temperature in the cavity, global and local Nusselt number. It has been found that an increase in amplitude or period increases the amplitude of the temperature in the core of cavity. The Nusselt number increases when the amplitude “a” of the imposed temperature increases, but this later is not affected by variation of the period. Originality/value The authors used LBM to simulate the convective flows in a cavity at high Ra, heated from below by tow imposed temperature profiles. Indeed, they simulate a local equipped by a solar water heater (SWH). The floor is subjected to a periodic heating: Sinusoidal heating (Case 1) for which the temperature varies sinusoidally (SWH without a supplement), and mono alternation heating (Case 2), the temperature evolves like a redressed signal (SWH with a supplement). The considered method has been successfully validated and compared with the previous work. The study has been conducted using several control parameters such as the signal amplitude and period in the case of turbulent convection. This allowed us to obtain a considerable set of results that can be used for engineering.
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Maden, M., D. E. Ong, D. Summerbell, and F. Chytil. "The role of retinoid-binding proteins in the generation of pattern in the developing limb, the regenerating limb and the nervous system." Development 107, Supplement (April 1, 1989): 109–19. http://dx.doi.org/10.1242/dev.107.supplement.109.
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We summarise existing data and describe new information on the levels and distribution of cellular retinoic acid-binding protein (CRABP) and cellular retinolbinding protein (CRBP) in the regenerating axolotl limb, the developing chick limb bud and the nervous system of the chick embryo in the light of the known morphogenetic effects of retinoids on these systems. In the regenerating limb, levels of CRABP rise 3- to 4-fold during regeneration, peaking at the time when retinoic acid (RA) is most effective at causing pattern duplications. The levels of CRBP are low. The potency of various retinoids in causing pattern respecification correlates well with the ability of these compounds to bind to CRABP. In the chick limb bud, the levels of CRABP are high and the levels of CRBP are low. Again the binding of various retinoids to CRABP correlates well with their ability to cause pattern duplications. By immunocytochemistry, we show that CRABP is present at high levels in the progress zone of the limb bud and is distributed across the anteroposterior axis in a gradient with the high point at the anterior margin. In the chick embryo, CRABP levels are high and CRBP levels are low. By immunocytochemistry, CRABP is localised primarily to the developing nervous system, labelling cells and axons in the mantle layer of the neural tube. These become the neurons of the commissural system. Also sensory axons label intensely with CRABP whereas motor axons do not and in the mixed nerves at the brachial plexus sensory and motor components can be distinguished on this basis. In the neural tube, CRBP only stains the ventral floor plate. Since the ventral floor plate may be a source of chemoattractant for commissural axons, we suggest on the basis of these staining patterns that RA may fulfill this role and thus be involved morphogenetically in the developing nervous system.
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Heiberg, Turid, Cathrine Austad, Tore K. Kvien, and Till Uhlig. "Performance of the Rheumatoid Arthritis Impact of Disease (RAID) score in relation to other patient-reported outcomes in a register of patients with rheumatoid arthritis." Annals of the Rheumatic Diseases 70, no. 6 (March 6, 2011): 1080–82. http://dx.doi.org/10.1136/ard.2010.143032.
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ObjectiveDelegates at the Outcome Measures in Rheumatology (OMERACT) 10 conference (Borneo, 4–8 May 2010) questioned how the new seven-domain Rheumatoid Arthritis Impact of Disease (RAID) score performs as a global measure. Score distributions and associations between the RAID score and patient-reported outcomes (PROs) and demographic variables were examined in a large sample of rheumatoid arthritis (RA) patients.Methods1086 patients in the Oslo RA Register responded to a postal survey with commonly used PROs. Bivariate associations between the RAID score and other measures are reported as Pearson correlation coefficients.ResultsThe mean RAID was 3.37±2.17. The distribution of the RAID score showed a slight floor effect: 17.5% had a score between 0 and 1, and 14.4% between 1 and 2, whereas only 1.0% and 0.3% had scores between 8 and 9, and 9 and 10, respectively. Correlations between the RAID score and the patient global assessment, Rheumatoid Arthritis Disease Activity Index, Short-Form (SF)-6D and EQ-5D were 0.82, 0.82, −0.77 and −0.73, respectively. Strong correlation was also seen between RAID and pain, the domain with highest weight, whereas correlations to measures of other RAID domains were moderate. The RAID score was higher in women than men (3.49 vs 2.95, p=0.001).ConclusionThe RAID score was correlated more strongly to other global measures than to PROs, reflecting single health domains.
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Morsli, Souad, Harry Ramenah, Mohammed El Ganaoui, and Rachid Bennacer. "Effect of aligned and misaligned ventilation opening affecting energy demand and air quality in buildings." European Physical Journal Applied Physics 83, no. 1 (July 2018): 10901. http://dx.doi.org/10.1051/epjap/2018180119.
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This work focuses on a horizontally ventilated cavity filled with air, heated on one side wall and cooled on the floor surface. Therefore, this study has been carried out for a convective loop induced for a fixed Rayleigh number Ra = 106 and horizontal ventilation (moderate Reynolds number Re = 100) where the injection is either in cooperating or opposing to the convective loop. The study undertaken concerns different opening position in order to analyze the energy efficiency of such ventilation and the corresponding indoor air quality. The results obtained indicate that the natural convection and the forced flow (ventilation) play an important role in the flow structure and the mixing ability, the heat exchange (cooling need) and the temperature comfort. The optimum ventilating position is a compromise in order to minimize the cooling demand, keep the mixing ability and reduce the temperature heterogeneity.
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Zhang, Guiping, Lili Zhou, Xiao Zhang, Xiaoli Gao, and Lingling Li. "Adoption of Pelvic Floor Ultrasonography Under Fuzzy Theory and Wavelet Transform Algorithm in Subtype Diagnosis of Bladder Prolapse." Journal of Medical Imaging and Health Informatics 11, no. 1 (January 1, 2021): 216–22. http://dx.doi.org/10.1166/jmihi.2021.3423.
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In order to improve the treatment accuracy of patients with different subtypes of bladder prolapse (BP), the value of ultrasonic images based on fuzzy theory (FT) and wavelet transform (WT) algorithm for detection and classification of subtypes of BP was discussed. First, the effects of fuzzy enhancement (FE) algorithm, WT enhancement algorithm, and FT combined wavelet algorithm on medical ultrasonic images were compared. Then, 144 cases of BP patients admitted to our hospital from October 2017 to October 2019 were selected as study objects. Ultrasound technology was used to examine the patient's bottom information. Finally, the data of posterior urethra-vesical angle (PUVA), rotation angle (RA) of urethra, mobility of bladder neck, lowest point of bladder and lowest point of posterior wall of bladder were measured under resting and Vslsalva conditions. According to Green classification, different subtypes of bladder prolapse were distinguished by the measurement data of pelvic floor (PF) ultrasound image. The clinical characteristics of Stress Urinary Incontinence (SUI), dysuria, and frequent urination of subtypes of BP were compared. The results showed that the ultrasonic image quality was the best by combining FT with WT; BP type II PUVA was more than 140°, BP type III PUVA was less than 140°, and the difference between the two was statistically significant (P < 0.05); the lowest point of the bladder in patients with type III BP was significantly higher than that in patients with type II BP (P < 0.05), and the neck mobility of type III bladder and the lowest point of the posterior wall of the bladder were significantly lower than that in patients with type II BP (P < 0.05); the difference of urethral RA between type II and type III of BP was not statistically significant (P > 0.05); the incidence of SUI in patients with type II BP was higher than that of type III BP (P < 0.05), and the incidence of dysuria in patients with type III BP was higher than that of type II BP (P < 0.05); the incidence of urinary frequency in patients with type II and type III BP was not statistically significant (P > 0.05), which showed that PF ultrasound based on FT and WT algorithm could effectively detect and identify different subtypes of BP.
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Westrich, Joseph T., Anthony M. Fuex, Patricia M. O'Neal, and Henry I. Halpern. "Evaluating Reservoir Architecture in the Northern Gulf of Mexico With Oil and Gas Chemistry." SPE Reservoir Evaluation & Engineering 2, no. 06 (December 1, 1999): 514–19. http://dx.doi.org/10.2118/59518-pa.
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Summary A post-development study was carried out at Bullwinkle Field in the Gulf of Mexico to develop and test geochemical methods for evaluating reservoir architecture, establish confidence in reservoir geochemistry technology, and provide a framework for surveillance work at Bullwinkle. In line with previous work, this study shows how fluid composition data can be used to obtain improved reservoir architecture interpretations. Geochemistry is a low-cost direct approach for determining reservoir architecture. When data are integrated with results from other tools and techniques, the final result is to improve decision making and production efficiency for both development and redevelopment projects. Introduction Throughout the life of an oil or gas field—from the time the count and placement of the first development wells are planned, to the last water-flood or sidetract/recompletion—a critical operational issue is the continuity and compartmentalization of reservoir units. Over the last 9 years, a number of papers have demonstrated that a variety of geochemical tools can be used to better define and constrain reservoir architecture interpretations,1–4 especially when resulting data are integrated with other geological, geophysical, and engineering information.1,5-7 The basic tenant applied in petroleum fingerprinting studies is deceptively simple—fluids in single reservoirs are compositionally homogeneous, while fluids in separate compartments show some degree of compositional heterogeneity. Differences are more important than similarities—much like pressure data, compositional homogeneity supports the idea of a continuous well-connected reservoir, although it usually does not prove it.5 Interpretations are complicated by a number of issues, including compositional grading, reservoir filling history, and insufficient time for mixing, but many published field studies support this general model.1-4,6,7 Geochemical fingerprinting technology has a number of advantages: as opposed to many static tools and methods, geochemical fluid data can be a direct indicator of fluid-flow barriers, much like PVT and production data,6,7,12 geochemical tools/methods are inexpensive, and most provide fast turn-around times, and the ability to work with core samples6–8 provides the opportunity for greater coverage, especially in areas with multiple stacked pay such as the Gulf of Mexico. Despite the applicability and promise of this new technology, its true value is not widely recognized in the industry. Consequently, it is not applied as much as it could be in appraisal, development, and re-development projects. An important reason for this lack of recognition/use is that a variety of issues and problems need to be addressed to increase our level of understanding about this technology. We need to know when it works, when it does not and why. Only then will this technology gain credibility and be used to its full potential. To help alleviate this situation, a geochemical study of the Bullwinkle Field was carried out to: identify the optimum analytical techniques and interpretation methods for application studies in the deepwater Gulf of Mexico; understand how to interpret fingerprinting data in the presence of compositional grading; increase Shell's confidence in reservoir geochemistry technology through a series of well-calibrated case studies; and participate in surveillance work aimed at planning subsequent field redevelopment work for the field. Study Area and Methods Bullwinkle field, in Green Canyon blocks 65 and 109 (Fig. 1), is considered a combination stratigraphic/salt-flank trap.9,10 The lower Pleistocene "J" sand package, which contains over 90% of the reserves at Bullwinkle, was mapped originally as four separate pay intervals (J1 through J4).9 Of these, the J2 sand (Fig. 2) contains the bulk of the recoverable reserves and has an estimated column height of about 1600 ft. Partly because of its size and importance, the J2 pay zone was the primary focus of this study. As discussed in this paper, the J2 pay interval is divided into the J2-RA and J2-RB reservoirs (Fig. 2). A comprehensive set of oils (n=18) and associated (dissolved) gas (n=16) samples, taken from nearly all of the initial oil producing wells, were analyzed in this study.
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Strasse, Wally auf der, Karen Regina Galvão de Oliveira, Lucas Menghin Beraldo, and Adriana Maria Wan Stadnik. "SYMMETRIC-ELECTROMYOGRAPHIC ANALYSIS IN THE EVALUATION OF SCOLIOSIS TREATMENT." Revista Brasileira de Medicina do Esporte 24, no. 6 (December 2018): 455–59. http://dx.doi.org/10.1590/1517-869220182406168696.
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ABSTRACT Introduction: Scoliosis is a three-dimensional deformity of the spine, characterized by a lateral shift that affects body posture. The Pilates Method (PM) promotes alterations in the biomechanics and neuromuscular activation pattern. Objective: The aim of this study was to analyze electromyography (EMG) and symmetrography (SMTG) technologies applied in the evaluation of neuromuscular and postural effects on right convex thoracolumbar scoliosis (RCTS) after applying a PM therapeutic protocol. Methods: This is an exploratory study of 5 male and female adolescents, with an average age of 14.4 years. The subjects underwent postural asymmetry assessments through SMTG and neuromuscular assessment through surface EMG of the trapezius (TRAP), erector spinae (ERE), oblique (OBLI) and rectus abdominis (RA) muscles. The electromyographic signals were processed in the temporal (EMGAmp) and spectral (EMGFmed) domains. The therapeutic protocol consisted of 24 sessions of Pilates floor exercises held twice a week with a duration of 45 minutes. Results: There was an improvement in scoliosis and asymmetric shoulders in one subject (20%) and in three other subjects with hip asymmetry. There was an improvement in one subject (33.33%), as demonstrated by SMTG. EMGAmp measurements demonstrated a significant difference between before and after (p≈0) and among the muscles (p≈0). EMGFmed measurements demonstrated that there was only a difference between before and after (p≈0). It was verified that the most noteworthy muscles in terms of EMGAmp were TRAP and ERE, emphasizing the existence of an increase in the mean EMGAmp for ERE. Muscle behavior for measurements in EMGFmed demonstrated a higher mean increase for RA and OBLI muscles. Conclusion: It is concluded that the EMG and SMTG technologies are important tests for monitoring the progress of scoliosis and in treatment decisions. Level of Evidence III; Diagnostic Studies - Investigating diagnostic tests.
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Djebali, Ridha, Mohamed Ammar Abbassi, and Ahlem Rouahi. "Conjugate Effects of Buoyancy and Magnetic Field on Heat and Fluid Flow Pattern at Low-to-Moderate Prandtl Numbers." International Letters of Chemistry, Physics and Astronomy 66 (May 2016): 79–95. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.66.79.
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This study aims to present a numerical investigation of unsteady two-dimensional natural convection of an electrically conducting fluid in a square medium under externally imposed magnetic field. A temperature gradient is applied between the two opposing side walls parallel to y-direction, while the floor and ceiling parallel to x-direction are kept adiabatic. The coupled momentum and energy equations associated with the Lorentz ‘decelerating’ force as well as the buoyancy force terms are solved using the single relaxation lattice Boltzmann (LB) approach. The flow is characterized by the Rayleigh number Ra (103-106), the Prandtl number Pr (0.01-10), the Hartman number Ha (0-100) determined by the strength of the imposed magnetic field and its tilt angle from x-axis ranging from 0° to 90°. The changes in the buoyant flow patterns and temperature contours due to the effects of varying the controlling parameters and associated heat transfer are examined. It was found that the developed thermal LB model gives excellent results by comparison with former experimental and numerical findings. Starting from the values 105 of the Rayleigh number Ra and Ha=0, the flow is unsteady multicellular for low Prandtl number typical of liquid metal. Increasing gradually Pr, the flow undergoes transition to steady bicellular. The transition occurs at a threshold value between Pr=0.01 and 0.1. Increasing more the Prandtl number, the flow structure is distorted due to the viscous forces which outweigh the buoyancy forces and a thermal stratification is clearly established. For high Hartman number, the damping effects suppress the unsteady behaviour and results in steady state with extended unicellular pattern in the direction of Lorentz force and the heat transfer rate is reduced considerably.
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Fahrizal, Effan, Teuku Budi Aulia, and Safwan Safwan. "EVALUASI KOMPONEN FISIK BANGUNAN PASAR SAYUR DAN BUAH PEUNAYONG KOTA BANDA ACEH TERHADAP UPAYA RELOKASI." Jurnal Arsip Rekayasa Sipil dan Perencanaan 1, no. 3 (September 11, 2018): 94–103. http://dx.doi.org/10.24815/jarsp.v1i3.11859.
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Peunayong area is a trade and service area, as well as a heritage tourist area located in Kuta Alam Subdistrict, Banda Aceh City. Since it was inaugurated in 2007 until now Peunayong Vegetable and Fruit Market is not working properly. Traders only want to sell on the first floor, and along the corridor of RA road. Kartini, while the second and third floors are not occupied. In addressing the issue, the Banda Aceh City Government seeks to relocate the Peunayong Market to an integrated market in Lampulo, which is currently under construction. This study aims to identify the factors that cause traders not to occupy the market building of Peunayong Vegetables and Fruits, to identify buyers' perceptions of relocation of Peunayong Vegetable and Fruit Market, and to evaluate the physical, non-physical, and Peunayong Vegetables Market. This research uses qualitative method through observation and interview, and quantitative method through questionnaires distribution. Respondents in this research are 70 traders, and 100 buyers. The results showed that the factors that caused the traders did not occupy the Peunayong Vegetable and Fruit Market building were the buyers did not want to rise to the 2nd floor, the lack of good accessibility for traders and buyers, the constraints of goods circulation, and the number of kiosks and stalls not enough to accommodate all traders. The buyer's perception of the market relocation effort of Vegetables and Peunayong Fruits is built a new market building that can accommodate all traders, have complete public facilities, and designs that follow SOP Kemendag. Evaluation of Peunayong Vegetable and Fruit Market building on the physical component, generally not in accordance with the prevailing regulation with 36.84% level of conformity
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Morsli, Souad, Rachid Bennacer, Mohammed El Ganaoui, Harry Ramenah, and Alain Carmasol. "Some flow patterns within ventilation strategy coupled to energy efficiency." European Physical Journal Applied Physics 88, no. 1 (October 2019): 10902. http://dx.doi.org/10.1051/epjap/2019190232.
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Energy and buildings are increasingly becoming subjects for investigations, especially for the indoor air quality domain coupled to energy demand. The physics of fluids flowing inside enclosures bring basic models to understand and build better schemes. This paper is devoted to studying ventilation strategies in regards to Indoor Air Quality (IAQ) and energy efficiency in floor refreshing houses. A room model is considered in a simplified level, as a cavity heated on the external sidewall and cooled on the bottom ground surface. The external air injector is at variable positions and interacting with the needed cooling power; the air quality (mixing ability) and thermal comfort are also studied. The cooling efficiency inside the considered volume and the average air temperature are analyzed for a given temperature difference characterizing the natural convection level (Rayleigh number, Ra = 106) and a horizontal ventilation (moderate Reynolds number Re = 102). An obtained complex flow structure indicates that the natural convection and the forced flow (ventilation) act directly on the resulting patterns, mixing ability, heat exchange which in a straight line affect the thermal comfort and in fine the energy cost (cooling requirement).
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Ruberte, E., P. Dolle, P. Chambon, and G. Morriss-Kay. "Retinoic acid receptors and cellular retinoid binding proteins. II. Their differential pattern of transcription during early morphogenesis in mouse embryos." Development 111, no. 1 (January 1, 1991): 45–60. http://dx.doi.org/10.1242/dev.111.1.45.
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In situ hybridization with 35S-labelled RNA probes was used to study the distribution of transcripts of genes coding for the retinoic acid receptors, RAR-alpha, -beta and -gamma, and the cellular binding proteins for retinoic acid (CRABP I) and retinol (CRBP I), in mouse embryos during the period of early morphogenesis. Primary mesenchyme formation was associated with CRBP I labelling of both epiblast and mesenchyme of the primitive streak, while the CRABP probe labelled the migrating primary mesenchyme cells. Neural crest cell emigration and migration were associated with CRABP labelling of both neural epithelium (excluding the floor plate) and neural crest cells, while CRBP I expression was restricted to basal and apical regions of the epithelium (excluding the floor plate). The strongest neuroepithelial signal for CRABP was in the preoptic hindbrain. RAR-beta was present in presomitic stage embryos, being expressed at highest levels in the lateral regions. RAR-alpha was associated with crest cell emigration and migration, while RAR-gamma was present in the primitive streak region throughout the period of neurulation. There was a change from RAR-beta to RAR-gamma expression at the junction between closed and open neural epithelium at the caudal neuropore. RAR-alpha and RAR-beta were expressed at specific levels of the hindbrain and in the spinal cord. These distribution patterns are discussed in relation to segmental expression patterns of other genes, and to maturational changes in the caudal neuropore region. The CRABP transcript distribution patterns correlated well with known target tissues of excess retinoid-induced teratogenesis (migrating primary mesenchyme and neural crest cells, preoptic hindbrain), providing further support for our hypothesis that cells expressing CRABP are those that cannot tolerate high levels of RA for their normal developmental function.
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Yamada, T. "Caudalization by the amphibian organizer: brachyury, convergent extension and retinoic acid." Development 120, no. 11 (November 1, 1994): 3051–62. http://dx.doi.org/10.1242/dev.120.11.3051.
Full textAbstract:
Caudalization, which is proposed to be one of two functions of the amphibian organizer, initiates posterior pathways of neural development in the dorsalized ectoderm. In the absence of caudalization, dorsalized ectoderm only expresses the most anterior (archencephalic) differentiation. In the presence of caudalization, dorsalized ectorderm develops various levels of posterior neural tissues, depending on the extent of caudalization. A series of induction experiments have shown that caudalization is mediated by convergent extension: cell motility that is based on directed cell intercalation, and is essential for the morphogenesis of posterior axial tissues. During amphibian development, convergent extension is first expressed all-over the mesoderm and, after mesoderm involution, it becomes localized to the posterior mid-dorsal mesoderm, which produces notochord. This expression pattern of specific down regulation of convergent extension is also followed by the expression of the brachyury homolog. Furthermore, mouse brachyury has been implicated in the regulation of tissue elongation on the one hand, and in the control of posterior differentiation on the other. These observations suggest that protein encoded by the brachyury homolog controls the expression of convergent extension in the mesoderm. The idea is fully corroborated by a genetic study of mouse brachyury, which demonstrates that the gene product produces elongation of the posterior embryonic axis. However, there exists evidence for the induction of posterior dorsal mesodermal tissues, if brachyury homolog protein is expressed in the ectoderm. In both cases the brachyury homolog contributes to caudalization. A number of other genes appear to be involved in caudalization. The most important of these is pintavallis, which contains a fork-head DNA binding domain. It is first expressed in the marginal zone. After mesoderm involution, it is present not only in the presumptive notochord, but also in the floor plate. This is in contrast to the brachyury homolog, whose expression is restricted to mesoderm. The morphogenetic effects of exogenous RA on anteroposterior specification during amphibian embryogenesis are reviewed. The agent inhibits archencephalic differentiation and enhances differentiation of deuterencephalic and trunk levels. Thus the effect of exogenous RA on morphogenesis of CNS is very similar to that of caudalization, which is proposed to occur through the normal action of the organizer. According to a detailed analysis of the effect of lithium on morphogenesis induced by the Cynops organizer, lithium has a caudalizing effect closely comparable with that of RA. Furthermore, lithium induces convergent extension in the prechordal plate, which normally does not show cell motility.(ABSTRACT TRUNCATED AT 400 WORDS)
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Li, Xiaoqiang, Xiuqin Yin, Zhenhai Wang, and Weihong Fan. "Interaction between decomposing litter and soil fauna of the Betula ermanii forest floor of the Changbai Mountains, China." Canadian Journal of Forest Research 44, no. 12 (December 2014): 1507–14. http://dx.doi.org/10.1139/cjfr-2014-0248.
Full textAbstract:
Soil fauna play a key role in litter decomposition as they influence the litter mass loss rate in terrestrial ecosystems. However, the interaction between decomposing litter and soil fauna has not been adequately addressed. We examine the interaction between different types of decomposing litter and soil fauna on the Betula ermanii Cham. (BE) forest floor of the Changbai Mountains, China, by measuring the mass loss of six litter species groups using litterbags with two sizes of mesh (4 mm and 0.01 mm) during a yearlong experiment. Soil fauna were identified at the order level. We found that soil fauna have a limited effect on litter mass loss at the initial stage of the experiment. Its positive effect became apparent at month 12 of the experiment. After 1 year, soil fauna increased the litter mass loss rate of the high-quality litter of Parasenecio komarovianus (Pojark.) Y.L. Chen (PK) by 7.02% and of the low-quality litter of Rhododendron aureum Georgi (RA) by 25.26%. BE + PK litter was associated with a significantly higher abundance of soil fauna at months 8 and 10 of the experiment and also with a significantly higher richness of soil fauna at month 10 of the experiment. At the end of the experiment, however, the Shannon–Wiener diversity index of soil fauna was not necessarily higher in mixed-species litter. Litter mixing did promote the abundance, richness, and diversity of soil fauna during the warm season in the high-quality litter substrate of BE + PK. Our results illustrate that the impact of soil fauna on the litter mass loss of both single- and mixed-species litterbags ranges from a limited impact to a positive impact as litter mass loss advances. The soil fauna contribute more to the litter mass loss of the low-quality litter with higher C to N ratios than to those with a low C to N ratio. The promoting effect of litter mixing on the soil faunal community composition is only short term and is dependent on substrate quality.
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Beckers, Esther, Casper Webers, Annelies Boonen, Peter M. ten Klooster, Harald E. Vonkeman, and Astrid van Tubergen. "Validation and implementation of a patient-reported experience measure for patients with rheumatoid arthritis and spondyloarthritis in the Netherlands." Clinical Rheumatology 39, no. 10 (April 21, 2020): 2889–97. http://dx.doi.org/10.1007/s10067-020-05076-6.
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Abstract Objectives To test the psychometric properties of the United Kingdom’s Commissioning for Quality in Rheumatoid Arthritis Patient-Reported Experience Measure (CQRA-PREM) in patients with spondyloarthritis (SpA) and rheumatoid arthritis (RA) and to implement this questionnaire in daily practice in the Netherlands. Methods After a forward-backward translation procedure into Dutch, the CQRA-PREM was tested into two quality registries in daily practice. Face validity was assessed with focus group interviews. Feasibility was evaluated through completion times and interpretability of domain scores through floor and ceiling effects. Internal consistency (Cronbach’s α coefficients) and homogeneity (corrected item-total correlations) were determined. Divergent validity was assessed by Spearman’s rank correlation coefficients (rs) between the average scores of domains and outcome measures. The CQRA-PREM was implemented in daily practice, and the results were used in quality improvement cycles. Results Face validity of the CQRA-PREM was good. The CQRA-PREM was completed by 282 patients with SpA and 376 with RA. Median time to complete the CQRA-PREM was 4.7 min. Ceiling effects were found in three out of seven domains. Internal consistency of nearly all domains was considered good (0.65 ≤ α ≤ 0.95). Thresholds for homogeneity were exceeded within three domains (rp > 0.7), suggesting item redundancy. Divergent validity showed that nearly all domains of the CQRA-PREM were at most weakly correlated with outcomes measures (− 0.3 ≤ rs ≤ 0.3). The CQRA-PREM could identify areas of improvement for providing patient-centered care. Conclusion The CQRA-PREM has acceptable psychometric properties and has shown to be a useful tool in evaluating quality of care from the patients’ perspective in the Netherlands. Trial registration SpA-Net is registered in the Netherlands Trial Registry (NTR6740). Key Points • The Commissioning for Quality in Rheumatoid Arthritis Patient-Reported Experience Measure (CQRA-PREM) is a valid measure for assessing patient-centeredness of rheumatology care. • The Dutch version of the CQRA-PREM shows acceptable psychometric properties. • The CQRA-PREM shows to be a useful tool in Plan-Do-Check-Act quality improvement cycles in the Netherlands. • The CQRA-PREM can be used for benchmarking and quality improvement of rheumatology services.
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Mingchun Luo. "Effects of Radiation on Temperature Measurement in a Fire Environment." Journal of Fire Sciences 15, no. 6 (November 1997): 443–61. http://dx.doi.org/10.1177/073490419701500602.
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Thermocouples have been widely used to measure temperature in research and industry. For the purpose of building fire experiments, the thermo couple has been and will be a major instrument to obtain the temperature field of the fire environment, and hence to quantify the intensity of building fire. It has been found that the radiation error significantly affects the measured tempera ture using thermocouples. However, this issue has not been carefully investigated in the area of building fire research. A suction pyrometer was designed and applied to a series of fire experiments in a full-scale experimental building-fire facility to avoid the effect of radiation on the measured temperature. It was found that the reading from a bare thermocou ple could be more than 100°C higher than the gas temperature obtained from the suction pyrometer during the flaming fire stage and more than 200°C higher dur ing the flashover stage. For a steady-state fire environment obtained from a propane gas burner fire, the radiation error was negligible in the hot upper level near the ceiling. However, the thermocouple significantly overestimated the gas temperature by more than 80°C in the cool lower level near the floor because of the radiation error. The tem perature predicted by the computational fluid dynamics model, CESARE-CFD fire model, was in good agreement with the measured temperature after the ra diation correction in the lower level and deviated slightly in the upper level.
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Kim, In-Ju. "Understanding Friction and Wear Behaviours of Smooth Resilient Surfaces: Application for Pedestrian Fall Safety Improvements." Advances in Materials Science and Engineering 2018 (October 16, 2018): 1–10. http://dx.doi.org/10.1155/2018/3280279.
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The recent literature identified that certain types of smooth floors and flooring materials showed good slip-resistance performance under moderately contaminated situations such as water wet and soapsuds-covered conditions. However, topographic structures of such flat floor/walkway surfaces are significantly changed by wear and tear developments with continuous ambulation. A number of reasons seem to be involved in flooring wear developments, but such changes may result in substantial losses of slip resistance (or traction) functions. Even though the importance of this issue is wide, it is scarce to find any systematic investigations on tribophysical characteristics of smooth floors (<10 µm in Ra roughness) and their wear impacts on traction performance. Moreover, it is difficult to find studies on wear progress of floors and its impacts on pedestrian fall safety assessments. This study focuses on exploring wear activities of smooth resilient floors and disclosing wear consequences on traction properties. To measure slip-resistance features and investigate wear advances of smooth resilient floors, dynamic friction tests were carried out amongst purposely arranged 4 flat specimens (polymethyl methacrylate: PMMA) and 3 shoes. Wear formations and progressions of the PMMA surfaces were methodically evaluated by observing surface profiles during the tests. The test outcomes evidently presented that initial surface features of the PMMA specimens were significantly modified by primary-, secondary-, and shared-wear mechanisms and significantly influenced traction performance. This study may have design applications for the safety enhancements of smooth floors/footpaths to preclude pedestrian fall incidents.