To see the other types of publications on this topic, follow the link: Oapi.
Journal articles on the topic 'Oapi'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Oapi.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Daniar, Rima, and Nurul Kholidah. "Effect of catalysts on the conversion of polystyrene plastic waste into fuel with the Catalytic Cracking Method." ALKIMIA : Jurnal Ilmu Kimia dan Terapan 4, no. 1 (February 29, 2020): 24–29. http://dx.doi.org/10.19109/alkimia.v4i1.5469.
Full textAbstract:
Polystyrene is useful product that widely used today. But when it becomes waste, Polystyrene can cause environmental problem such as air pollution, soil contamination, as well as economical resistence due to the increase of space and disposal costs. On the other hand Polystyrene can be converted into fuel. It is expected can be a solution of the problem. The aim of this research is to convert polystyrene plastic waste into useful fuel with catalytic cracking process. Zeolit and Al2O3 was used as catalyst in this research as musch as 8 % feed. Temperature set at 250 oC. At the optimum reaction condition (catalyst Al2O3 and the length of cracking time is 30 minutes) the liquid yield of catalytic cracking process was 29.40 %. Physical properties like density, spgr, oAPI gravity and calorific value of fuel samples is determined and compared to gasoline standard. The result showed that density, spgr, oAPI gravity and calorific value was close to the density, spgr, oAPI gravity and calorific value of gasoline standard.
2
Liu, Daxue, Jun Wu, and Xin Xu. "Multi-agent reinforcement learning using ordinal action selection and approximate policy iteration." International Journal of Wavelets, Multiresolution and Information Processing 14, no. 06 (November 2016): 1650053. http://dx.doi.org/10.1142/s0219691316500533.
Full textAbstract:
Multi-agent reinforcement learning (MARL) provides a useful and flexible framework for multi-agent coordination in uncertain dynamic environments. However, the generalization ability and scalability of algorithms to large problem sizes, already problematic in single-agent RL, is an even more formidable obstacle in MARL applications. In this paper, a new MARL method based on ordinal action selection and approximate policy iteration called OAPI (Ordinal Approximate Policy Iteration), is presented to address the scalability issue of MARL algorithms in common-interest Markov Games. In OAPI, an ordinal action selection and learning strategy is integrated with distributed approximate policy iteration not only to simplify the policy space and eliminate the conflicts in multi-agent coordination, but also to realize the approximation of near-optimal policies for Markov Games with large state spaces. Based on the simplified policy space using ordinal action selection, the OAPI algorithm implements distributed approximate policy iteration utilizing online least-squares policy iteration (LSPI). This resulted in multi-agent coordination with good convergence properties with reduced computational complexity. The simulation results of a coordinated multi-robot navigation task illustrate the feasibility and effectiveness of the proposed approach.
3
Blakeney, Michael, and Getachew Mengistie. "Intellectual property policy formulation in Africa." Queen Mary Journal of Intellectual Property 11, no. 1 (February 18, 2021): 98–113. http://dx.doi.org/10.4337/qmjip.2021.01.06.
Full textAbstract:
This article examines continental, sub-regional and national initiatives in the formulation of intellectual property policy Africa. The article is divided into seven parts. The first looks at the relationship between IP and economic development. The second part examines the role of IP regional integration and trade. The third part looks at African regional trade agreements. Next, the article surveys the activities of sub-regional IP systems in Africa: the African Regional Intellectual Property Organization (ARIPO) and the Organisation Africaine de la Propriété (OAPI). The fifth part looks at the recent formation of the Pan African Intellectual Property Organization (PAIPO) and its relationship with ARIPO and OAPI. The sixth part gives a brief overview of the efforts made in designing national IP polices. The concluding section summarizes the IP policy-making process in Africa.
4
Nwabueze, Caroline Joëlle. "Challenges of Transnational Trademark Law Practice: The Case of Nigerian Companies’ Brands in OAPI States." Revue générale de droit 45, no. 1 (July 8, 2015): 321–47. http://dx.doi.org/10.7202/1032041ar.
Full textAbstract:
Nigeria industrial growth has turned the country into an indispensable economic support for its neighbours. Only for the case of Cameroon, Nigeria has been the leading supplier with respectively 22% and 17.8% of imports in 2011 and 2012 with trade amounting to 328 billion FCFA per annum. This results in part from Nigerian companies’ exportations in local markets. Nigerian trademarks related to cosmetics, furniture, electronics, and pharmaceutical goods abound in neighbouring countries. However, a strengthening of Nigerian companies in regional markets encompasses strategies to avoid infringing on the trademark rights. Such strategies should include the consideration of special trademarks features by different institutions of the intellectual property (IP) system in the relevant neighbour export markets. This is by the mere fact that the legal status of those goods, although physical property, relies mainly on the material law applicable, which is trademark in the present case. Because the principle of territoriality requires that trademark protection be sought in the place where the goods are sold—and trademark applications filed in each country in which protection is sought—, Nigerian companies planning to outsource some business activity in neighbour markets will seek compliance with trademarks norms applicable in the Organisation africaine de la propriété intellectuelle (OAPI) of which those countries—Benin, Cameroon, Chad, and Guinea—are part. The trade partnership between companies from a common law trademark background on one hand, and civil law intellectual property community on the other, inevitably raises some frictions and trademarks issues. This article analyses the trademark challenges arising from Nigerian companies’ business decision to enter OAPI markets and export goods and services. The article firstly underlines the issues to be taken into consideration, including registration and enforcement of the companies’ marks in OAPI. Then the paper simultaneously reviews the dissimilarities issues between the Nigerian Trademark Act and the OAPI Trademark System to which the Nigerian companies are confronted. If trademark protection makes it easier for an enterprise to access transnational markets, the establishment of a Trademark Community with neighbouring countries helps for sure national industries to establish partnerships with other firms for sustainable development in the areas such as production, marketing, distribution or delivery of goods and services. In light of the trademark harmonisation in the European Union internal market, the present paper concludes by recommending the creation of a Trademark Community in the West and Central African region between Nigeria and its neighbouring countries.
5
Kongolo, Tshimanga. "The New Oapi Agreement as Revised in February 1999." Journal of World Intellectual Property 3, no. 5 (November 1, 2005): 717–35. http://dx.doi.org/10.1111/j.1747-1796.2000.tb00151.x.
Full text
6
Cantika, Ria, Hefly Agustian Akbar, Arizal Aswan, K. A. Ridwan, Adi Syakdani, Sahrul Effendy, and Muhammad Taufik. "Pengolahan Limbah Plastik Jenis Polypropylene (PP) dan Low Density Polyethylene (LDPE) Menjadi Bahan Bakar Cair Melalui Proses Catalytic Thermal Cracking Menggunakan Katalis FCC." Jurnal Pendidikan dan Teknologi Indonesia 2, no. 10 (October 24, 2022): 437–45. http://dx.doi.org/10.52436/1.jpti.235.
Full textAbstract:
Setiap tahunnya penggunaan plastik yang semakin meningkat mengakibatkan jumlah sampah plastik yang sulit terurai semakin tinggi. Upaya mengelola sampah plastik melalui penimbunan dan pembakaran dinilai kurang tepat dan berdampak buruk bagi lingkungan. Proses Catalytic Thermal Cracking (CTC) merupakan metode yang tepat dan menguntungkan untuk mengolah limbah plastik menjadi bahan bakar cair. Pada penelitian ini, pengolahan limbah plastik jenis Polypropylene dan Low Density Polyethylene menjadi bahan bakar cair melalui Proses CatalytIc Thermal Cracking berlangsung pada temperatur CTC 200 oC, 350 oC, 300 oC, 350 oC dan 400oC dengan jumlah katalis FCC sebanyak 10%. Tujuan dari penelitian ini adalah mengetahui bagaimana pengaruh temperatur CTC terhadap % yield, sifat fisik dan komposisi senyawa bahan bakar cair yang diperoleh. Dari penelitian yang dilakukan, didapat temperatur optimum Catalytic Thermal Cracking pada Polypropylene dan Low Density Polyethylene yaitu temperatur 400 oC dengan jumlah % yield produk bahan bakar cair tertinggi sebesar 30,29 % untuk Polypropylene dengan nilai Density, oApi Gravity, Viscosity dan Calorific Value masing-masing yaitu: 0,7536 gr/ml, 0,8010 cSt dan 11.206 Kcal/Kg. Sedangkan untuk Low Density Polyethylene % yield produk bahan bakar cair tertinggi sebesar 23,09 % dengan nilai Density, oApi Gravity, Viscosity dan Calorific Value masing-masing yaitu: 0,7508 gr/ml, 0,9856 cSt dan 11.215 Kcal/Kg.
7
Ogiriki, Shadrach Olise, Jennifer Oyindamola Adepoju, Adeyinka Sikiru Yusuff, and Victor Anochie. "Physical Properties of Agbabu and Yegbata Bitumen in Nigeria." Journal of Applied Science & Process Engineering 5, no. 1 (March 30, 2018): 227–41. http://dx.doi.org/10.33736/jaspe.427.2018.
Full textAbstract:
This experimental work evaluates the physical properties of Abagbu and Yegbata bitumen from Nigeria with comparison with that of Canada being the world largest producer of crude oil from bitumen. This study employed the American Society for Testing and Materials (ASTM) methods in conducting laboratory experiments in order to determine the viscosity, specific gravity, API gravity, pour point and flash point. A Gas Chromatograph (GC) was used to determine the hydrocarbon content of the bitumen samples. Test results show that the bitumen samples have specific gravity of 1.01 with a 0.9962 OAPI for Yegbata, while the Agbabu bitumen sample had 8.599 specific gravity and 10.54 OAPI. Kinematic viscosity ranges of 1.0×102 – 3.3×104 and 1.6×103 – 5.6×104, flash point of 288oC and 282oC and pour point of 44oC and 47oC. The gas chromatography analysis showed that the samples contained 46.35% and 7.59% saturates, 21.63% and 64.39% aromatics and 32.03% and 28.01% resins for Agbabu and Yegbata respectively. In comparison with Athabasca bitumen, the results were similar. The assessment and comparison of these properties with the properties of bitumen from Athabasca in Canada reveals that any surface or subsurface crude bitumen gotten from Agbabu and Yegbata in Ondo State, Nigeria can be exploited using similar technologies, if not the same as the technologies being used in Athabasca, Canada
8
Harlivia, Rara, Tahdid Tahdid, and Sahrul Effendy A. "Pengaruh Persen Katalis Zeolit Alam Terhadap Yield Bahan Bakar Cair Proses Pirolisis dari Limbah Plastik Polypropylene." Jurnal Pendidikan dan Teknologi Indonesia 2, no. 11 (November 18, 2022): 453–59. http://dx.doi.org/10.52436/1.jpti.241.
Full textAbstract:
Meningginya konsumsi energi tidak terbarukan tiap tahun terutama minyak bumi sedangkan cadangan minyak bumi di Indonesia semakin menipis dan meningkatnya penggunaan plastik yang tidak seimbang dengan pengolahan limbah merupakan masalah yang dihadapi saat ini. Salah satu upaya yang dapat menangani permasalahan tersebut adalah dengan metode pirolisis. Melalui pirolisis, plastik dapat diolah dengan aman menjadi produk cair yang bisa menjadi alternatif sumber bahan bakar. Penelitian ini bertujuan untuk mengetahui pengaruh katalis zeolit alam terhadap yield yang dihasilkan dan karakteristik dari yield tersebut. Bahan baku yang digunakan berupa plastik jenis polypropylene dan katalis zeolit alam dengan variasi 0%, 2%, 4%, 6% dan 8%, pada penelitian ini dilakukan dengan menganalisis pengaruh variasi katalis zeolit dengan temperatur 200±10oC dan waktu 180 menit. Berdasarkan penelitian yang dilakukan %yield terbanyak didapatkan pada persen katalis 8% sebanyak 88,93%. Katalis zeolit alam berpengaruh terhadap produk yang dihasilkan. Semakin besar persen zeolit alam berpengaruh terhadap produk yang dihasilkan dimana semakin besar persen zeolit alam maka nilai persen yield, densitas dan viskositas yang dihasilkan akan semakin naik, akan tetapi berbanding dengan nilai oAPI dan nilai kalor yang menurun seiring dengan bertambahnya persen zeolit alam. Nilai yield tertinggi didapatkan pada zeolit alam 8% sebesar 88,93% sedangkan terendah pada zeolit alam 0% dengan persentase yield sebesar 65,96%. Karakteristik produk yang dihasilkan mendekati standar bensin dengan nilai densitas 0,7889–0,7967 gr/ml, viskositas sebesar 0,9712–1,1126 cSt, oAPI sebesar 45,78–47,33o, nilai kalor sebesar 11.067,1–11.093,0 kal/gr dan titik nyala sebesar 23oC.
9
Harris, Kimberly A., Zhiyuan Zhou, Michelle L. Peters, Sarah G. Wilkins, and Ronald R. Breaker. "A second RNA-binding protein is essential for ethanol tolerance provided by the bacterial OLE ribonucleoprotein complex." Proceedings of the National Academy of Sciences 115, no. 27 (June 18, 2018): E6319—E6328. http://dx.doi.org/10.1073/pnas.1803191115.
Full textAbstract:
OLE (ornate, large, extremophilic) RNAs comprise a class of structured noncoding RNAs (ncRNAs) found in many extremophilic bacteria species. OLE RNAs constitute one of the longest and most widespread bacterial ncRNA classes whose major biochemical function remains unknown. In the Gram-positive alkaliphile Bacillus halodurans, OLE RNA is abundant, and localizes to the cell membrane by association with the transmembrane OLE-associated protein called OapA (formerly OAP). These characteristics, along with the well-conserved sequence and structural features of OLE RNAs, suggest that the OLE ribonucleoprotein (RNP) complex performs important biological functions. B. halodurans strains lacking OLE RNA (∆ole) or OapA (∆oapA) are less tolerant of cold (20 °C) and short-chain alcohols (e.g., ethanol). Here, we describe the effects of a mutant OapA (called PM1) that more strongly inhibits growth under cold or ethanol stress compared with strains lacking the oapA gene, even when wild-type OapA is present. This dominant-negative effect of PM1 is reversed by mutations that render OLE RNA nonfunctional. This finding demonstrates that the deleterious PM1 phenotype requires an intact RNP complex, and suggests that the complex has one or more additional undiscovered components. A genetic screen uncovered PM1 phenotype suppressor mutations in the ybzG gene, which codes for a putative RNA-binding protein of unknown biological function. We observe that YbzG protein (also called OapB) selectively binds OLE RNA in vitro, whereas a mutant version of the protein is not observed to bind OLE RNA. Thus, YbzG/OapB is an important component of the functional OLE RNP complex in B. halodurans.
10
Rajesh, Sarigama, Jiali Zhai, Calum J. Drummond, and Nhiem Tran. "Novel pH-Responsive Cubosome and Hexosome Lipid Nanocarriers of SN-38 Are Prospective for Cancer Therapy." Pharmaceutics 14, no. 10 (October 12, 2022): 2175. http://dx.doi.org/10.3390/pharmaceutics14102175.
Full textAbstract:
pH-responsive nanoparticles enable the selective delivery of a chemotherapeutic agent to tumours while reducing adverse effects. Herein we synthesised four novel aminolipids and developed pH-responsive nanostructured lipid nanoparticles (LNP), which exhibited a slow-releasing hexagonal structure (H2) at physiological pH and quick release bicontinuous cubic phase (Q2) at the acidic tumour pH. The nanoparticles were used to encapsulate and control the release of the chemotherapeutic agent SN-38. High-throughput formulation techniques were employed to fabricate LNP by mixing various amounts of aminolipid with monoolein (MO). The effect of aminolipids on MO self-assembled structures was studied using small-angle X-ray scattering (SAXS) at various pH values. Out of the four studied aminolipid-MO LNP systems, the nanoparticles containing N-(Pyridin-4-ylmethyl) oleamide (OAPy-4) or N-(2(piperidin-1yl)ethyl) oleamide (OAPi-1) exhibited a pH-induced H2 to Q2 phase transition in a tumour-relevant pH range (pH 5.5–7.0). SN-38 is 1000 times more efficacious than the commercially available prodrug irinotecan. However, low solubility in water and instability at physiological pH makes it unsuitable for clinical use. SN-38 was loaded into LNP containing MO and aminolipid OAPy-4. The drug loading and entrapment efficiency were determined, and the results indicated that the aqueous solubility of SN-38 loaded in LNP dispersions was ~100 times higher compared to the solubility of the pure drug in aqueous solution. Furthermore, we demonstrated that the in vitro SN-38 release rate from LNPs was faster at lower pH (pH 5) than at neutral pH. Therefore, pH-responsive LNPs developed in this study can potentially be employed in delivering and controlling the release of the potent drug SN-38 to tumour sites.
11
Gazaro, Wéré Régine. "Plant variety protection: Which system of protection in the member states of OAPI?" World Patent Information 28, no. 2 (June 2006): 127–31. http://dx.doi.org/10.1016/j.wpi.2005.12.001.
Full text
12
Ngombe, Laurier Yvon. "Audiovisual Work in the Member States of the African Intellectual Property Organization (OAPI)." Journal of World Intellectual Property 9, no. 4 (July 2006): 445–57. http://dx.doi.org/10.1111/j.1422-2213.2006.00286.x.
Full text
13
Quansah, Anthony, Zhirong Xiao, and Tresor Ntaryamira. "Parametric Investigation of Plane Frame Structure Using Excel Vba And Sap2000 oapi Based Programming." International Journal of Engineering Research and Applications 07, no. 07 (August 2017): 14–23. http://dx.doi.org/10.9790/9622-0707091423.
Full text
14
Hula, Ibnu Rawandhy N., Adimawati Helingo, Sitti Nur Adawiyah Jassin, and Suharia Sarif. "Transcription of Pegon Gorontalo Arabic Orthography, Malay and Arabic Standard: A Contraceptive Linguistic Analysis." `A Jamiy : Jurnal Bahasa dan Sastra Arab 11, no. 2 (August 28, 2022): 322. http://dx.doi.org/10.31314/ajamiy.11.2.322-341.2022.
Full textAbstract:
Penelitian ini bertujuan untuk mentranskripsi tuturan yang berbentuk bunyi ke dalam bentuk tulisan Ortografi Arab Pegon Gorontalo (OAPG) dan membandingkannya dengan Ortografi Arab Pegon Melayu (OAPM) dan Ortografi Arab standar (OAS). Metode penelitian yang digunakan adalah kualitatif deskriptif dengan pendekatan linguistic kontrastif. Data dikumpulkan berbentuk dokumen manuskrip dari kitab dikili yang berasal dari empat kabupaten di Provinsi Gorontalo. Data OAPG dianalisis dengan menggunakan teknik rekam catat, kemudian membandingkannya dengan OAPM dan OAS. Hasil penelitian ini menunjukkan bahwa ditemukan beberapa persamaan sekaligus perbedaan antara Ortografi Arab Pegon Gorontalo (OAPG) dengan OAPM dan OAS. Persamaan antara OAPG dengan OAPM yakni; (1) Kedua bahasa ini menggunakan ortografi pegon ch [څ], ny [ڽ], ng [ڠ] dan g [ڬ] (2) Memiliki fonem, aksara bunyi vokal O dan E, serta menggunakan dua belas ortografi Arab standar urutan hija’i. Persamaan antara OAPG dengan OAS, yakni; 1) OAPG menggunaan enam belas ortografi OAS (ا-ب-ت-ج-د-ر-س-غ-ف-ك-ل-م-ن-و-ء-ي) berdasarkan urutan hija’i, namun tidak memiliki dua belas konsonan OAS. 2) OAPG dan OAS sama-sama memiliki aksara yang disambung dan dipisah, serta menggunakan semua tanda diakritik Arab standar. Adapun perbedaan transkripsinya adalah: 1) OAPG tidak membedakan penggunaan tanda diakritik [E] menjadi [é] pepet dan [e] taling. 2) Memiliki suku kata yang dimulai dengan [nt-نْت] dan [ng-ڠْڬ], 3) OAPG menggunakan fonem Arabic standar [f-ف] dan bukan fonem pegon [p-ڤ]. 4) OAPG tidak menggunakan ortografi [ڎ/ڊ] dan [ڟ] untuk fonem [dh] [th], 5) OAPG memiliki tujuh fonem pembeda yang tidak dimiliki oleh Ortografi Arab Standar.
15
Pisani, Francesco, Laura Simone, Maria Mola, Manuela De Bellis, Maria Mastrapasqua, Maddalena Ruggieri, Maria Trojano, Grazia Nicchia, Maria Svelto, and Antonio Frigeri. "Host-Cell Type Dependent Features of Recombinant Human Aquaporin-4 Orthogonal Arrays of Particles—New Insights for Structural and Functional Studies." Cells 8, no. 2 (February 2, 2019): 119. http://dx.doi.org/10.3390/cells8020119.
Full textAbstract:
The CNS plasma-membrane water channel aquaporin-4 (AQP4) is expressed as two major isoforms able to aggregate into supramolecular assemblies known as ‘orthogonal arrays of particles’ (OAPs). OAP subnanometric features are largely unknown mainly because a method for the expression, isolation, and crystallization of integral human OAPs has not been developed. Here, the human OAP-forming isoform M23-AQP4 was expressed in insect and mammalian cell lines and AQP4 and OAP features evaluated. Native size exclusion chromatography was employed to isolate and analyze authentically folded OAPs, and neuromyelitis optica (NMO)-specific sandwich ELISA was developed to test OAP-integrity. The results demonstrate that in insect cells most AQP4 remains intracellular and unfolded and that OAPs are largely disassembled after the detergent extraction step. In mammalian cells, AQP4 showed regular plasma membrane targeting and OAPs exhibited strong post-extraction stability. Starting from the mammalian cell expression system, we isolated authentically folded OAPs. Together these data suggest a new strategy for expressing and isolating integral recombinant human OAPs and providing new insights into the cell-type dependent OAP-assembly and post-extraction stability, potentially useful to design new approaches for structural and functional studies of OAP and for other plasma membrane proteins organized into supramolecular structures.
16
Tankoano, Amadou. "La protection des obtentions végétales dans les états menbres de l'organisation africaine de la propriété intellectuelle(OAPI)." Revue internationale de droit économique XVII, 1, no. 1 (2003): 103. http://dx.doi.org/10.3917/ride.171.0103.
Full text
17
Cucuzza, Raffaele, Marco Martino Rosso, Angelo Aloisio, Jonathan Melchiorre, Mario Lo Giudice, and Giuseppe Carlo Marano. "Size and Shape Optimization of a Guyed Mast Structure under Wind, Ice and Seismic Loading." Applied Sciences 12, no. 10 (May 11, 2022): 4875. http://dx.doi.org/10.3390/app12104875.
Full textAbstract:
This paper discusses the size and shape optimization of a guyed radio mast for radiocommunications. The considered structure represents a widely industrial solution due to the recent spread of 5G and 6G mobile networks. The guyed radio mast was modeled with the finite element software SAP2000 and optimized through a genetic optimization algorithm (GA). The optimization exploits the open application programming interfaces (OAPI) SAP2000-Matlab. Static and dynamic analyses were carried out to provide realistic design scenarios of the mast structure. The authors considered the action of wind, ice, and seismic loads as variable loads. A parametric study on the most critical design variables includes several optimization scenarios to minimize the structure’s total self-weight by varying the most relevant parameters selected by a preliminary sensitivity analysis. In conclusion, final design considerations are discussed by highlighting the best optimization scenario in terms of the objective function and the number of parameters involved in the analysis.
18
Vladkova, Todorka G., Alexander Chr Alaminov, and Milka G. Pankova. "A Study of the Interactions Between Oligoamidephosphate (OAPh) and Curatives in a Sulphenamide-Accelerated Sulphur Vulcanizing System." Journal of Polymer Engineering 19, no. 2 (March 1, 1999): 95–108. http://dx.doi.org/10.1515/polyeng-1999-0203.
Full textAbstract:
Abstract The possible interactions between oligoamidephosphate (OAPli) and the curatives of a sulphenamide-accelerated sulphur vulcanizing system were studied by differential scanning calorimetry, IR-spectroscopy, and X-ray analysis. The interactions in double mixtures were between OAPh and zinc oxide (ZnO) and OAPh and sulphur. The OAPh/ZnO interaction that starts at room temperature seems to be the key for understanding the peculiarities of sulphenamide-accelerated sulphur vulcanization in the presence of OAPh.
19
Prakash, Jay, and Ayşe T. Daloglu. "Teaching-learning-based optimization of unbraced steel frames with semi-rigid connections and column bases." Journal of Structural Engineering & Applied Mechanics 6, no. 1 (March 30, 2023): 27–44. http://dx.doi.org/10.31462/jseam.2023.01027044.
Full textAbstract:
The teaching-learning optimization (TLBO) technique is applied to unbraced steel frames with semi-rigid beam-to-column connections and semi-rigid column-to-base connections. The algorithm for design produces optimized steel frames by choosing appropriate sections from a set of standard steel sections. These standard steel sections, including wide-flange profiles (W), are provided by the American Institute of Steel Construction (AISC). The first example is subjected to the displacement, inter-story drift, and stress constraints of AISC-Load and Resistance Factor Design (LRFD) regulations. In addition, the displacement and stress limitations of the AISC-Allowable Stress Design (ASD) standard and the geometric (size) requirements are implemented in the last two examples. In finite element analysis, optimal designs of three alternative unbraced frames are performed with and without semi-rigid beam-to-column and column-to-base plate connections. All optimization techniques are encoded in the high-level programming language C# version 17.4.4 to integrate with SAP2000 version 22's Open Application Programming Interface (OAPI). The analysis results indicate that the rigidity of connections is determining parameter in the weight optimization of unbraced steel frames.
20
Dinh-Cong, D., T. Nguyen-Thoi, and Duc T. Nguyen. "A FE model updating technique based on SAP2000-OAPI and enhanced SOS algorithm for damage assessment of full-scale structures." Applied Soft Computing 89 (April 2020): 106100. http://dx.doi.org/10.1016/j.asoc.2020.106100.
Full text
21
Bello, Ibrahim. "L’appréciation du risque de confusion à l’épreuve du principe de la territorialité des droits de propriété industrielle dans l’espace OAPI." Uniform Law Review 27, no. 3 (August 1, 2022): 441–59. http://dx.doi.org/10.1093/ulr/unac026.
Full textAbstract:
Résumé La délimitation du cadre géographique dans lequel le risque de confusion s’apprécie est consubstantielle de la protection des droits querellés dans ledit cadre. C’est l’application du principe de la territorialité des droits qui veut qu’un droit n’est garanti que dans les limites du territoire du pays dans lequel la protection a été acquise. Dès lors, il était récurrent que des personnes exploitant des marques se trouvent démunies de tout argument dans les pays où celles – ci avaient été abusivement déposées. L’application difficultueuse de ce principe a donné l’occasion à une doctrine relativement majoritaire d’envisager la consécration d’un autre principe à savoir celui de l’universalité. Cette règle suggère que, l’acquisition de droits sur la marque, par voie de dépôt ou d’usage dans un pays donné interdit à un tiers de s’approprier une telle marque dans le pays appliquant ce principe. Cette théorie a un inconvénient majeur qui réside dans la difficulté pratique d’effectuer les recherches internationales avant tout dépôt de marques. Acquis sous une législation consacrant l’universalité, le droit de propriété sur la marque souffrait donc d’une certaine fragilité. La solution semble avoir été trouvée en droit communautaire par la consécration de la supranationalité des droits de propriété industrielle. Cette consécration quoique très controversée a été réalisé en droit OAPI car on observe une survivance des titres nationaux à cotés desquels les droits nationaux demeurent valides. Sur ce point nous préconisons l’application du principe de la supranationalité selon le modèle de l’Union Européenne au sein de laquelle un droit est protégé indifféremment de l’Etat de l’Union dans lequel il a été acquis. Ce qui permet d’appréhender efficacement tout risque de confusion. Le juge camerounais, quant à lui, a déjà amorcé ce revirement dans une décision qui, nous l’espérons ne restera pas sans échos.
22
Daloglu, Ayse T., Musa Artar, Korhan Ozgan, and Ali İ. Karakas. "Optimum Design of Braced Steel Space Frames including Soil-Structure Interaction via Teaching-Learning-Based Optimization and Harmony Search Algorithms." Advances in Civil Engineering 2018 (2018): 1–16. http://dx.doi.org/10.1155/2018/3854620.
Full textAbstract:
Optimum design of braced steel space frames including soil-structure interaction is studied by using harmony search (HS) and teaching-learning-based optimization (TLBO) algorithms. A three-parameter elastic foundation model is used to incorporate the soil-structure interaction effect. A 10-storey braced steel space frame example taken from literature is investigated according to four different bracing types for the cases with/without soil-structure interaction. X, V, Z, and eccentric V-shaped bracing types are considered in the study. Optimum solutions of examples are carried out by a computer program coded in MATLAB interacting with SAP2000-OAPI for two-way data exchange. The stress constraints according to AISC-ASD (American Institute of Steel Construction-Allowable Stress Design), maximum lateral displacement constraints, interstorey drift constraints, and beam-to-column connection constraints are taken into consideration in the optimum design process. The parameters of the foundation model are calculated depending on soil surface displacements by using an iterative approach. The results obtained in the study show that bracing types and soil-structure interaction play very important roles in the optimum design of steel space frames. Finally, the techniques used in the optimum design seem to be quite suitable for practical applications.
23
Gnintedem, Patrick Juvet Lowé. "Les organisations régionales africaines de la propriété intellectuelle et l’accès aux médicaments dans des situations de pandémie." African Yearbook of International Law Online / Annuaire Africain de droit international Online 24, no. 1 (December 19, 2019): 88–123. http://dx.doi.org/10.1163/22116176_02401007.
Full textAbstract:
Souvent frappée par des crises sanitaires, l’Afrique est constamment confrontée aux difficultés d’accès aux médicaments résultant de la protection des droits de propriété intellectuelle (DPI). L’avènement de la pandémie de Covid-19 rappelle des débats devenus vifs ces trois dernières décennies, relativement au sort à réserver aux DPI couvrant les médicaments nécessaires à la prise en charge des populations. À cet effet, les organisations régionales africaines de propriété intellectuelle, dans le cadre de l’Union africaine, mais surtout de l’Organisation régionale africaine de la propriété intellectuelle (ARIPO) et de l’Organisation africaine de la propriété intellectuelle (OAPI) disposent de règles pertinentes destinées à régir l’utilisation des DPI. Entre incitation à la recherche innovante tout en ménageant des flexibilités qui atténuent la rigueur des DPI, et crainte de restreindre l’accès aux résultats de la recherche, le droit généré par ces organisations régionales fournit-il des réponses appropriées pour l’accès aux médicaments? Tantôt encouragé par les DPI existants, tantôt perturbé en raison d’enjeux spécifiques comme la question de la protection des médicaments traditionnels, l’accès aux médicaments est une préoccupation centrale pour les Organisations régionales africaines désireuses de jouer leur partition dans la recherche de l’équilibre entre droits privatifs des titulaires de DPI et intérêt général associé à l’accès aux médicaments.
24
Hao, W., V. S. Molchanov, Yu M. Chesnokov, P. R. Podlesnyi, and O. E. Philippova. "Effect of Electrostatic Interactions in Wormlike Micelles of Surfactants Based on Betaine and Charged Tertiary Amine with the Same Hydrophobic Groups." Colloid Journal 86, no. 2 (April 2024): 306–14. http://dx.doi.org/10.1134/s1061933x23601373.
Full textAbstract:
Abstract The viscoelastic properties and structure of solutions of mixed wormlike micelles based on a zwitterionic surfactant, oleylamidopropyldimethylcarboxybetaine (OAPB), and positively charged oleylamidopropyldimethylamine (OAPA) have been studied at different ratios between the components. At a small fraction of the cationic surfactant, OAPA, the solution exhibits viscoelastic properties characteristic of semidiluted solutions of entangled wormlike micelles, the presence of which has been confirmed by cryogenic electron microscopy data. It has been found that, as the molar fraction of the charged surfactant increases to 0.1, the viscosity and relaxation time of the solutions decrease by a factor of three, and the values of the storage modulus remain unchanged at short stress action times. The studied surfactants have a similar structure; therefore, when replacing zwitterionic OAPB molecules by positively charged OAPA molecules, the main factor of variations in the properties and structure is the enhancement of the electrostatic repulsion on the micelle surface. It has been shown that this factor leads to a decrease in the average length of micelles and an increase in their number, which have a weak effect on the rheological properties of the system as long as the length of the micelles is larger than the length of the subchains in the network. With an increase in the molar fraction of OAPA from 0.1 to 0.5, the viscosity and relaxation time drop drastically by several orders of magnitude and the viscoelastic response of the solution is lost; i.e., the network is destroyed. This transition from a semidilute solution to a dilute one is explained by a decrease in the length of the wormlike micelles and the formation of spherical ones. Cryogenic electron microscopy images have confirmed the formation of a mixture of long and short wormlike micelles with spherical micelles at an OAPA molar fraction of 0.5.
25
Domingo, Ephraim Viernes. "Coping strategies in oral academic presentations of international undergraduate students in a Philippine university: a small-case study." Language Learning in Higher Education 11, no. 1 (May 1, 2021): 93–113. http://dx.doi.org/10.1515/cercles-2021-2011.
Full textAbstract:
Abstract Higher education students are increasingly becoming aware of the importance of being successful in oral academic presentations (OAP) in their academic endeavors. For English as a second language students in English-medium institutions, it also provides them with opportunities for language socialization. However, succeeding in the delivery of an OAP comes with various challenges emerging from linguistic and psychological factors. This small-case study explores OAPs as an oral academic socialization activity by documenting the strategies that 13 international undergraduate students in a large private Philippine university use to cope with the difficulties facing them in preparing and presenting an OAP. Using language socialization as the theoretical framework and semi-structured interviews to gather data, it identifies and explains eight personal strategies (six still employed and two no longer used) and discusses various factors that play a vital role in applying these strategies. The three most commonly used strategies are adopted to ensure a successful and acceptable OAP, typically a graded task. The two least frequently used ones are yet to be employed successfully. In applying these strategies, students not only perform the required academic task but are also engaged in different levels and frequencies of language socialization before and during the delivery of an OAP. Pedagogical implications in the use of OAPs as an academic task for language socialization in higher education are also discussed.
26
Kholidah, Nurul. "Pengaruh Temperatur terhadap Persentase Yield pada Proses Perengkahan Katalitik Sampah Plastik menjadi Bahan Bakar Cair." ALKIMIA : Jurnal Ilmu Kimia dan Terapan 2, no. 1 (June 29, 2018): 28–33. http://dx.doi.org/10.19109/alkimia.v2i1.2259.
Full textAbstract:
Peningkatan konsumsi energi dan peningkatan timbulan sampah plastik merupakan dua permasalahan besar yang muncul seiring dengan pertumbuhan ekonomi dan pertambahan penduduk. Salah satu jenis sampah plastik polystyrene yang dapat diolah menjadi bahan bakar cair dengan proses perengkahan adalah styrofoam. Pada penelitian ini, proses perengkahan sampah plastik polystyrene dilakukan dengan proses perengkahan katalitik dengan menggunakan katalis Al2O3. Penelitian ini bertujuan untuk mengetahui pengaruh temperatur terhadap persentase yield produk dan karakteristik produk yang dihasilkan dari proses perengkahan katalitik sampah plastik polystyrene menggunakan katalis Aluminium Oksida. Proses perengkahan katalitik dilakukan didalam reaktor jenis fixed bed, dimana proses berlangsung pada suhu 150 oC, 200 oC, 250 oC dan 300 oC dengan waktu perengkahan 60 menit dan berat katalis 6% dari berat styrofoam yaitu 250 gram. Dari hasil penelitian diperoleh persentase yield cairan tertinggi sebesar 17,0% pada temperatur 250 oC, sedangkan karakteristik bahan bakar cair yang mendekati karakteristik gasoline yaitu pada temperature 250 oC, lama waktu perengkahan 60 menit dan berat katalis 6%, dimana masing-masing diperoleh nilai densitas sebesar 0.763 g/mL, specific gravity sebesar 0.778 dan oAPI gravity sebesar 50.2. Untuk bahan bakar cair yang diperoleh dari hasil perengkahan polystyrene pada suhu 150 oC, 200 oC dan 300 oC masih berada dalam rentang toleransi karakteristik bensin. Bahan bakar cair yang dihasilkan dari proses perengkahan katalitik dianalisa menggunakan alat GC-MS, dimana hasil analisa menunjukkan bahwa bahan bakar cair tersebut termasuk kedalam fraksi bensin.
27
Wang, Dejiang, and Haojie Lu. "Development of a BIM Platform for the Design of Single-Story Steel Structure Factories." Buildings 14, no. 3 (March 10, 2024): 747. http://dx.doi.org/10.3390/buildings14030747.
Full textAbstract:
Traditional design methods for single-story steel structure factories are characterized by low levels of digitalization and high error rates. To deal with these problems, a building information modeling (BIM) platform for the design of single-story steel structure factories was developed in this paper, which aimed to improve the design process for such structures. Firstly, the components of the factory were categorized, and the Revit API was employed to automate the generation of the BIM model. Load applications and combinations were then established using the Revit API, which relied on a set of predefined parameters. Secondly, this paper proposed the creation of a dedicated database for data exchange between BIM software and finite element analysis software. Additionally, the SAP2000 Open Application Programming Interface (OAPI) was employed for the automated construction and analysis of the SAP2000 structural model. Finally, the innovative use of Dynamo–Revit API hybrid programming allowed for the visualization of internal forces directly within the Revit environment, significantly diminishing the dependency on standalone FEA software. The application results obtained on a project demonstrated that the developed platform markedly improves the efficiency of design single-story steel structure factories and ensures the accuracy of the structural analysis. This confirms that the developed platform can transform the traditional design process by integrating advanced digital tools, thereby providing a novel approach to the design of single-story steel structure factories.
28
Yang, Yang, Kimberly A. Harris, Danielle L. Widner, and Ronald R. Breaker. "Structure of a bacterial OapB protein with its OLE RNA target gives insights into the architecture of the OLE ribonucleoprotein complex." Proceedings of the National Academy of Sciences 118, no. 9 (February 22, 2021): e2020393118. http://dx.doi.org/10.1073/pnas.2020393118.
Full textAbstract:
The OLE (ornate, large, and extremophilic) RNA class is one of the most complex and well-conserved bacterial noncoding RNAs known to exist. This RNA is known to be important for bacterial responses to stress caused by short-chain alcohols, cold, and elevated Mg2+concentrations. These biological functions have been shown to require the formation of a ribonucleoprotein (RNP) complex including at least two protein partners: OLE-associated protein A (OapA) and OLE-associated protein B (OapB). OapB directly binds OLE RNA with high-affinity and specificity and is believed to assist in assembling the functional OLE RNP complex. To provide the atomic details of OapB–OLE RNA interaction and to potentially reveal previously uncharacterized protein–RNA interfaces, we determined the structure of OapB fromBacillus haloduransalone and in complex with an OLE RNA fragment at resolutions of 1.0 Å and 2.0 Å, respectively. The structure of OapB exhibits a K-shaped overall architecture wherein its conserved KOW motif and additional unique structural elements of OapB form a bipartite RNA-binding surface that docks to the P13 hairpin and P12.2 helix of OLE RNA. These high-resolution structures elucidate the molecular contacts used by OapB to form a stable RNP complex and explain the high conservation of sequences and structural features at the OapB–OLE RNA-binding interface. These findings provide insight into the role of OapB in the assembly and biological function of OLE RNP complex and can guide the exploration of additional possible OLE RNA-binding interactions present in OapB.
29
Widner, Danielle L., Kimberly A. Harris, Lukas Corey, and Ronald R. Breaker. "Bacillus halodurans OapB forms a high-affinity complex with the P13 region of the noncoding RNA OLE." Journal of Biological Chemistry 295, no. 28 (May 6, 2020): 9326–34. http://dx.doi.org/10.1074/jbc.ra120.012676.
Full textAbstract:
Noncoding RNAs (ncRNAs) longer than 200 nucleotides are rare in bacteria, likely because bacterial genomes are under strong evolutionary pressures to maintain a small genome size. Of the long ncRNAs unique to bacteria, the OLE (ornate, large, extremophilic) RNA class is among the largest and most structurally complex. OLE RNAs form a ribonucleoprotein (RNP) complex by partnering with at least two proteins, OapA and OapB, that directly bind OLE RNA. The biochemical functions of the OLE RNP complex remain unknown, but are required for proper adaptation to certain environmental stresses, such as cold temperatures, short chain alcohols, and high magnesium concentrations. In the current study, we used electrophoretic mobility shift assays to examine the binding of OLE RNA fragments by OapB and found that OapB recognizes a small subregion of OLE RNA, including stem P13, with a dissociation constant (KD) of ∼700 pm. Analyses with mutated RNA constructs, and the application of in vitro selection, revealed that strong binding of OLE RNA by OapB requires a stem containing a precisely located single-nucleotide bulge and a GNRA tetraloop. Although the vast majority of bacteria with the ole gene also have the oapB gene, there are many whose genomes contain oapB but lack ole, suggesting that OapB has other RNA partners in some species that might exhibit similar structural features.
30
E.Y.H, Bobobee, Yakanu P.N., Marenya M.O, and Ochanda J.P.O. "THE TEK MECHANICAL CASSAVA HARVESTER DEVELOPMENT IN GHANA – CHALLENGES, OPPORTUNITIES AND PROSPECTS FOR CASSAVA PRODUCTION IN AFRICA." Journal of Engineering in Agriculture and the Environment 5, no. 1 (September 30, 2019): 20. http://dx.doi.org/10.37017/jeae.v5i1.51.
Full textAbstract:
The low level of engineering technology inputs into agriculture is a major constraint hindering themodernization of agriculture and food production in many parts of Africa. Cassava (Manihot esculentaCrantz), is a climate resilient crop grown by smallholder farmers in most sub-Saharan Africa countries.Cassava provides dietary carbohydrates for over 800 million people globally. It is also a bio-fuel sourcethat can replace fossil fuels. Africa is not visible in the cassava industrialisation and export marketbecause it depends on over-aged farmers, who use manual tools and traditional production methods thatdo not attract the youth. One major challenge to all year-round cassava production for industry andexport in Africa is the time consuming, labour intensive and expensive manual harvesting method.Manual cassava harvesting is full of drudgery and takes 5 to 10 minutes to uproot a plant, depending onsoil condition. The main objective of this paper is to demonstrate and popularise an innovativemechanical cassava harvester developed in Ghana (OAPI patent No. 17219), to mechanise andmodernise cassava production in Africa. The device harvests at a rate of one plant per second or lessespecially when the ground is hard. For the innovation to be disseminated successfully, tractor operatorsand smallholder farmers must be trained to acquire mechanised production methods. Cassava farmersneed to change from planting in the traditional haphazard manner to adopt row and ridge planting tocomply with mechanical harvesting at plant maturity. The device is to up-scale and increase cassavaproduction for food security, industrial use and export in Africa.
31
Amalia, Dhea Nurul, Anindya Indrita Putri, Della Agustia Marhani, Putri Vina Amalia, Anwar Muhamad Rizki, and Keryanti Keryanti. "Biogasoline Production from Shallot Skin Waste with KOH-Clay Catalyst to Create Clean Energy." Fluida 16, no. 2 (November 30, 2023): 85–91. http://dx.doi.org/10.35313/fluida.v16i2.4591.
Full textAbstract:
Finding alternative fuels to replace fossil fuels has been made easier by the rise in the consumption of fuels like petrol and the fall in the production of national petroleum exploration activities. This research has been prompted using biomass as an alternative fuel. The primary raw material is shallot skin waste because it has enough lignocellulosic content to be used, one of which is to manufacture biogasoline by using the characteristics of petrol E10. A KOH-Clay catalyst is employed in a thermal and catalytic reaction to influence the reaction's pace. Starting with raw material preparation, conversion procedure, purification, and investigation of the physical properties of biogasoline at specific temperature fluctuations for an hour, the KOH-Clay catalyst is pretreated and characterised. It was discovered through this research that the montmorillonite KOH-Clay content was 5.73, indicating that the catalyst is hygroscopic and absorbs non-polar molecules, making it suitable for use as a catalyst with a pH of 6. As a result, at 60°C temperature circumstances, the best%yield results were attained of 35.025%. While the density value (0.950 gr/cm3) and colour (specific gravity, brownish yellow, and clear/bright) of the experimental results do not meet predetermined standards, they do when viewed from the viewpoint of physical parameters such as specific gravity (0.8358), oAPI biogasoline (37.794), and calorific value (18807.65 Btu/Ib). However, leftover shallot peels generally have the potential to be utilised as clean renewable energy.
32
Enakrire, Rexwhite Tega, and Joseph M. Ngoaketsi. "Open access practices: roadmap to research paper publications in academic institutions." Library Hi Tech News 37, no. 5 (February 28, 2020): 13–15. http://dx.doi.org/10.1108/lhtn-01-2020-0003.
Full textAbstract:
Purpose The purpose of this paper is to investigate open access practices (OAPs): a roadmap to research paper publications in academic institutions. The rationale that necessitates this scenario was the dwindling nature of the inability of researchers and lecturers/academics in African academic institutions to access related materials in their subject areas, while also advancing effort to publish their research papers in open access. Design/methodology/approach This paper applied a qualitative research approach, in which literature was harvested from Web of Science for developing and writing the research paper. Findings This paper establishes that OAP, when embraced, could advance and transform research paper publication in higher education institutions because its practices are globally welcome. The authors reiterate that considering the benefits accrued to OAPs, knowledge gap in terms of literature and methodological approach still exists in academic institutions in Africa; hence, the authors promote OAPs as a roadmap for research paper publications in academic institutions. It is expected that by OAPs, researchers would no longer struggle to harvest literature, of theses, dissertations and other research papers, deposited in institutional repositories required for deepening their research activities because those literature studies or those documents have to be paid for through subscription fees of published papers and publishing in open access by journals. This is what most academics have experienced because, most times, the literature which academics harvest from the internet and different institutional repositories and databases is already paid for by the different institutions that housed the literature where it is domiciled. For instance, most academic library institutions in the world pay for subscription fees of research papers and documents. This is to advance and facilitate deepened research activities in their institutions, when researchers, academics and students want to harvest materials through their university library websites. Originality/value This paper, which considers OAP as a roadmap to research paper publications in academic institutions in Africa, is insightful and unique considering the wave of OAP globally.
33
Cunningham, Jessica, Shawn Binkley, Tanya Uritsky, Stephen Saw, Sonal Patel, Tiffany Lee, Keith W. Hamilton, Kathleen Degnan, Lauren Dutcher, and Vasilios Athans. "168. Syndrome-Based Analysis of Oral Antimicrobial Stewardship Opportunities at Hospital Discharge." Open Forum Infectious Diseases 8, Supplement_1 (November 1, 2021): S193—S194. http://dx.doi.org/10.1093/ofid/ofab466.370.
Full textAbstract:
Abstract Background Suboptimal oral antibiotic prescriptions (OAPs) are prevalent at discharge and contribute to treatment failure, resistance, toxicity, and excess costs. Syndrome-specific prescribing patterns have not been widely described at discharge, nor have specific reasons for excessive treatment durations (the most commonly cited prescribing error). Methods Retrospective cohort of patients discharged from a general medicine service at an academic hospital with ≥1 OAP for urinary tract infection (UTI), skin and soft tissue infection (SSTI), or lower respiratory tract infection (LRTI). Study period varied to include a random sample of encounters occurring after the most recent institutional guideline update for each syndrome. Exclusions: multiple infectious indications, discharge against medical advice, parenteral antibiotics at discharge, pregnancy, cystic fibrosis, and immunocompromising conditions. Discharge OAPs were assessed for suboptimal selection, dose, frequency, or duration according to institutional guidelines (with secondary adjudication). Results Analysis included 160 encounters: 70 UTIs, 66 SSTIs, and 24 LRTIs. Of 71 (44%) culture-positive infections, Enterobacterales (61%) and Streptococcus spp. (15%) were most often identified. In total, 180 OAPs were issued – most commonly cefpodoxime (21%), cefadroxil (18%), and doxycycline (17%). Overall, 99 (62%) encounters were associated with a suboptimal discharge OAP. Of 138 suboptimal characteristics identified, suboptimal duration was most frequent (57%), specifically excessive duration (45%). Proportion of suboptimal OAPs and their underlying reasons are analyzed by syndrome in Figures 1 and 2, respectively. Miscalculation (39%), intentional selection of guideline-discordant duration (29%), and omission of inpatient antibiotic days (19%) were the most frequent reasons for suboptimal duration (Fig. 3). Conclusion Suboptimal discharge OAPs were common for all studied syndromes, most notably SSTI. Excessive duration was a key driver, with reasons for inappropriate duration previously undescribed. Duration miscalculation and selection of appropriate treatment duration are key areas to focus electronic health record enhancements, provider education, and antimicrobial stewardship efforts. Disclosures All Authors: No reported disclosures
34
Verbavatz, J. M., T. Ma, R. Gobin, and A. S. Verkman. "Absence of orthogonal arrays in kidney, brain and muscle from transgenic knockout mice lacking water channel aquaporin-4." Journal of Cell Science 110, no. 22 (November 15, 1997): 2855–60. http://dx.doi.org/10.1242/jcs.110.22.2855.
Full textAbstract:
Freeze-fracture electron microscopy (FFEM) of kidney collecting duct, muscle, astrocytes in brain, and other mammalian tissues has revealed regular square arrays of intramembrane particles called orthogonal arrays of particles (OAPs). Their possible role in membrane structure and transport have been proposed, and their absence or decrease has been noted in a variety of hereditary and acquired diseases. A transgenic mouse lacking water channel AQP4 was used to show that AQP4 is the OAP protein. FFEM was done on kidney, skeletal muscle, and brain from AQP4 wild-type [+/+], heterozygous [+/−] and knock-out [-/-] mice. The [-/-] mice did not express detectable AQP4 protein, but were grossly indistinguishable from [+/+] mice. FFEM was done on blinded samples of kidney, brain and muscle from 9 mice. In all 6 kidney samples from [+/+] and [+/−] mice, OAPs similar to those in AQP4-transfected CHO cells were found in basolateral membranes of collecting duct principal cells. In all muscle and brain samples from [+/+] and [+/−] mice, OAPs of identical ultrastructure to those in kidney were seen, but in smaller patch sizes. OAPs were not seen in any sample from [-/-] mice. Label-fracture analysis using a peptide-derived AQP4 polyclonal antibody showed immunogold labeling of OAPs in AQP4-expressing CHO cells. These studies provide direct evidence that AQP4 is required for formation of OAPs and is a component of OAPs, thus establishing the identity and function of OAPs.
35
O'Shea, Sebastian J., Jonathan Crosier, James Dorsey, Waldemar Schledewitz, Ian Crawford, Stephan Borrmann, Richard Cotton, and Aaron Bansemer. "Revisiting particle sizing using greyscale optical array probes: evaluation using laboratory experiments and synthetic data." Atmospheric Measurement Techniques 12, no. 6 (June 6, 2019): 3067–79. http://dx.doi.org/10.5194/amt-12-3067-2019.
Full textAbstract:
Abstract. In situ observations from research aircraft and instrumented ground sites are important contributions to developing our collective understanding of clouds and are used to inform and validate numerical weather and climate models. Unfortunately, biases in these datasets may be present, which can limit their value. In this paper, we discuss artefacts which may bias data from a widely used family of instrumentation in the field of cloud physics, optical array probes (OAPs). Using laboratory and synthetic datasets, we demonstrate how greyscale analysis can be used to filter data, constraining the sample volume of the OAP and improving data quality, particularly at small sizes where OAP data are considered unreliable. We apply the new methodology to ambient data from two contrasting case studies: one warm cloud and one cirrus cloud. In both cases the new methodology reduces the concentration of small particles (<60 µm) by approximately an order of magnitude. This significantly improves agreement with a Mie-scattering spectrometer for the liquid case and with a holographic imaging probe for the cirrus case. Based on these results, we make specific recommendations to instrument manufacturers, instrument operators and data processors about the optimal use of greyscale OAPs. The data from monoscale OAPs are unreliable and should not be used for particle diameters below approximately 100 µm.
36
Fitzgerald, Heather M., Jason Shepherd, Hollie Bailey, Mia Berry, Jack Wright, and Maxine Chen. "Characterization and Treatment Goals of Patients on Long-Acting Injectable vs Oral Antipsychotics: Results from a Patient/Caregiver/Psychiatrist Survey." CNS Spectrums 26, no. 2 (April 2021): 154. http://dx.doi.org/10.1017/s109285292000245x.
Full textAbstract:
AbstractBackgroundPatient preferences in schizophrenia (SCZ), including identification of key goals and outcomes for treatment and relative importance of certain treatment goals to patients, have been assessed by several studies. However, there continues to be a lack of sufficient evidence on US patient attitudes and perceptions towards treatment goals and pharmacotherapy options in SCZ, especially taking into context long-acting injectable antipsychotics (LAIs) in this disease area. This lack of evidence is further pronounced in caregivers of individuals with SCZ. The objective of this analysis was to characterize patients with SCZ on LAIs vs patients on oral antipsychotics (OAPs) and evaluate the treatment goals of patients in each group.MethodsThis was a real-world, cross-sectional survey of US psychiatrists, patients =18 years old with a diagnosis of SCZ, and caregivers. Data was collected using the Disease Specific Programme (DSP) methodology, which has been previously published. Psychiatrists (n=120) completed detailed record forms for next 8 consecutive outpatients and 2 inpatients matching inclusion criteria, including non-interventional clinical and subjective assessments. The same patients and their caregivers, if present, were invited by their psychiatrist to voluntarily complete a separate survey.ResultsOf 1135 patients on treatment where the physician provided survey data; 251 were on an LAI, and 884 were on an OAP. Mean (SD) time to SCZ diagnosis for those on an LAI was 10.3 (12.0) years vs 7.8 (10.5) years for those on OAPs. More patients in the LAI vs OAP group were being treated as an inpatient (27.1% vs 15.7%, respectively; p<0.0001). Patients on an LAI reported being on their current medication regimen for less time (mean 1.7 years) vs those on OAPs (mean 2.5 years) (p=0.0093). More patients on LAIs were unemployed due to disability vs those on OAPs (56.1% vs 39.5%, respectively), and less patients on LAIs were able to work part-time or full-time (21.1% or 4.1%) vs those on OAPs (23.2% or 11.4%). More patients on an LAI had a caregiver vs those on OAPs (37.3% vs 26.1%, respectively; p=0.0011). Regarding the most important treatment goals reported by patients, both groups reported similar preferences for decrease in disease symptoms (62% on LAI vs 65% on OAPs) and thinking more clearly (53% on LAI vs 46% on OAPs); however, a numerically higher proportion of LAI patients reported that the current medication helped decrease hospitalizations due to relapse vs those on OAPs (38% vs 32%, respectively).DiscussionGiven the characteristics of patients participating in this real-world survey, those on LAIs exhibited qualities which indicate a higher severity of illness vs those on OAPs. Results suggest that treatment with LAIs is still mainly being provided to patients later in the disease course and/or who have adherence problems, despite a growing body of evidence of utility in younger patients earlier in the course of illness.FundingOtsuka Pharmaceutical Development & Commercialization, Inc. and Lundbeck LLC
37
Zhang, Quanwu, Weixing Shi, and Yanze Wang. "Human-Induced Vibration Control of Floor Structures Using MTMD System Optimized by MATLAB-SAP2000 Interface." Buildings 14, no. 2 (January 23, 2024): 308. http://dx.doi.org/10.3390/buildings14020308.
Full textAbstract:
Under human-induced excitations, a floor structure may suffer excessive vibrations due to its large span and low damping ratio. Vertical vibrations, in particular, can become intolerable during resonance events. A tuned mass damper (TMD) is a widely used single-degree-of-freedom dynamic vibration absorber. To enhance the serviceability of a floor structure, a multiple TMD (MTMD) system finds broad application. The parameters of the MTMD must be carefully designed to achieve satisfactory performance. However, existing studies often employ a simplified model of the floor structure with closely spaced modes to optimize the parameters of MTMD. Nonetheless, an oversimplified floor model can lead to a reduction in its control effect. To solve this problem, this study utilizes the OAPI facility of SAP2000 to build a connection with MATLAB. A multi-objective optimization algorithm based on the artificial fish swarm algorithm (AFSA) for MTMD is developed in MATLAB, while the finite element model of a real floor structure is built in SAP2000. The locations of the MTMD system are initially specified in SAP2000 and, through the proposed MATLAB–SAP2000 interface, data can be exchanged between them. Based on the structural dynamic responses to external excitations in SAP2000, the optimization process for the MTMD is carried out in MATLAB. Concurrently, the parameters of the MTMD in SAP2000 are iteratively adjusted until they reach their final optimal values. To underscore the enhancements brought about by the proposed interface and optimization method, a comparative case study is conducted. A group of MTMDs, optimized using a conventional method, is presented for reference. The numerical results indicate that, overall, the proposed MTMD system exhibits superior control effectiveness and robustness.
38
Crane, Jonathan M., Chiwah Lam, Andrea Rossi, Tripta Gupta, Jeffrey L. Bennett, and A. S. Verkman. "Binding Affinity and Specificity of Neuromyelitis Optica Autoantibodies to Aquaporin-4 M1/M23 Isoforms and Orthogonal Arrays." Journal of Biological Chemistry 286, no. 18 (March 21, 2011): 16516–24. http://dx.doi.org/10.1074/jbc.m111.227298.
Full textAbstract:
Autoantibodies against astrocyte water channel aquaporin-4 (AQP4) are highly specific for the neuroinflammatory disease neuromyelitis optica (NMO). We measured the binding of NMO autoantibodies to AQP4 in human astrocyte-derived U87MG cells expressing M1 and/or M23 AQP4, or M23 mutants that do not form orthogonal array of particles (OAPs). Binding affinity was quantified by two-color fluorescence ratio imaging of cells stained with NMO serum or a recombinant monoclonal NMO autoantibody (NMO-rAb), together with a C terminus anti-AQP4 antibody. NMO-rAb titrations showed binding with dissociation constants down to 44 ± 7 nm. Different NMO-rAbs and NMO patient sera showed a wide variation in NMO-IgG binding to M1 versus M23 AQP4. Differences in binding affinity rather than stoichiometry accounted for M1 versus M23 binding specificity, with consistently greater affinity of NMO-IgG binding to M23 than M1 AQP4. Binding and OAP measurements in cells expressing different M1:M23 ratios or AQP4 mutants indicated that the differential binding of NMO-IgG to M1 versus M23 was due to OAP assembly rather than to differences in the M1 versus M23 N termini. Purified Fab fragments of NMO-IgG showed similar patterns of AQP4 isoform binding, indicating that structural changes in the AQP4 epitope upon array assembly, and not bivalent cross-linking of whole IgG, result in the greater binding affinity to OAPs. Our study establishes a quantitative assay of NMO-IgG binding to AQP4 and indicates remarkable, OAP-dependent heterogeneity in NMO autoantibody binding specificity.
39
Silberstein, Claudia, Richard Bouley, Yan Huang, Pingke Fang, Nuria Pastor-Soler, Dennis Brown, and Alfred N. Van Hoek. "Membrane organization and function of M1 and M23 isoforms of aquaporin-4 in epithelial cells." American Journal of Physiology-Renal Physiology 287, no. 3 (September 2004): F501—F511. http://dx.doi.org/10.1152/ajprenal.00439.2003.
Full textAbstract:
Aquaporin-4 (AQP4) water channels exist as heterotetramers of M1 and M23 splice variants and appear to be present in orthogonal arrays of intramembraneous particles (OAPs) visualized by freeze-fracture microscopy. We report that AQP4 forms OAPs in rat gastric parietal cells but not in parietal cells from the mouse or kangaroo rat. Furthermore, the organization of principal cell OAPs in Brattleboro rat kidney is perturbed by vasopressin (arginine vasopressin). Membranes of LLC-PK1 cells expressing M23-AQP4 showed large, abundant OAPs, but none were detectable in cells expressing M1-AQP4. Measurements of osmotic swelling of transfected LLC-PK1 cells using videomicroscopy, gave osmotic water permeability coefficient ( Pf) values (in cm/s) of 0.018 (M1-AQP4), 0.019 (M23-AQP4), and 0.003 (control). Quantitative immunoblot and immunofluorescence showed an eightfold greater expression of M1- over M23-AQP4 in the cell lines, suggesting that single-channel pf (cm3/s) is much greater for the M23 variant. Somatic fusion of M1- and M23-AQP4 cells ( Pf = 0.028 cm/s) yielded OAPs that were fewer and smaller than in M23 cells alone, and M1-to-M23 expression ratios (∼1:4) normalized to AQP4 in M1 or M23 cells indicated a reduced single-channel pf for the M23 variant. Expression of an M23-AQP4-Ser111E mutant produced ∼1.5-fold greater single-channel pf and OAPs that were up to 2.5-fold larger than wild-type M23-AQP4 OAPs, suggesting that a putative PKA phosphorylation site Ser111 is involved in OAP formation. We conclude that the higher-order organization of AQP4 in OAPs increases single-channel osmotic water permeability by one order of magnitude and that differential cellular expression levels of the two isoforms could regulate this organization.
40
Kaymakcalan, Marina D., Jenafer Thomas, Kristin Nowakowski, Shital Shukla, Anne C. Le, Christina Cibotti, Monica Syngal, and Jim W. Doolin. "Clinical pharmacist prescription review and modification for oral antineoplastic medications at an academic medical center." JCO Oncology Practice 19, no. 11_suppl (November 2023): 64. http://dx.doi.org/10.1200/op.2023.19.11_suppl.64.
Full textAbstract:
64 Background: Collaboration between oncology providers and pharmacy teams has improved the safety of oral antineoplastic (OA) prescribing, but opportunities remain for improvements in care delivery. To this end, starting in March 1, 2021, the Dana Farber Cancer Institute Specialty Pharmacy implemented a new workflow - clinical verification of new specialty prescriptions by dedicated OA clinical pharmacists (OAPs) prior to prescription processing. To reduce the impact of initial prescription errors on efficiency and safety, one component of clinical verification was to expand the purview of OAPs to make certain modifications to prescriptions that could be automatically processed without requiring prescriber re-signing. Automatically processed prescription modifications include corrections to quantity or days supply, indication of cycle length or days on/off therapy, and clarification of directions. Here we report on the impact of this portion of the clinical verification program. Methods: OAP prescription modification (OAP-PM) was introduced on November 1, 2022. To assess the impact on efficiency, we conducted a pre-post analysis of the proportion of prescription modifications taking > 60 minutes to complete for 6 months before and after OAP-PM introduction. Using prescription-level data, we analyzed co-variates including pre-/post-OAP-PM, patient age (continuous), site (academic vs. network), communication with someone other than the primary prescriber (y/n), and medication category (anti-neoplastic vs. supportive). We used control charts to explore the contribution of specific medications and sites that might share best practices or be the focus of subsequent, more focused improvement projects. Results: From May 1, 2022 to May 1, 2023, 458 prescription modifications were completed, 180 pre- and 278 post-OAP-PM. The proportion of prescriptions requiring > 60 minutes to complete decreased from 29.4% to 19.8% (p = 0.0184). In multivariable regression, the significant predictors of prescription taking > 60 minutes to complete were pre-OAP-PM (LR 4.9, p = 0.027); network (LR 20.8, p < 0.0001); and communication with someone other than the primary provider (LR 18.6, p < 0.0010). Control charts demonstrated all sites were within 3-sigma limits pre- and post-OAP-PM, but with wide limits at many sites. Individual medications could not be meaningfully analyzed due to the small sample sizes. Conclusions: OAP-PM successfully reduced the proportion of OA prescriptions taking more than an hour to modify. This may be a useful workflow change for other specialty pharmacies to adopt to improve the efficiency of OA care. Additional work is needed to understand whether site-, provider- or medication-specific changes can improve upon this model.
41
Jorgačevski, Jernej, Robert Zorec, and Maja Potokar. "Insights into Cell Surface Expression, Supramolecular Organization, and Functions of Aquaporin 4 Isoforms in Astrocytes." Cells 9, no. 12 (December 7, 2020): 2622. http://dx.doi.org/10.3390/cells9122622.
Full textAbstract:
Aquaporin 4 (AQP4) is the most abundant water channel in the central nervous system (CNS). Its expression is confined to non-neuronal glial cells, predominantly to astrocytes that represent a heterogeneous glial cell type in the CNS. The membrane of astrocyte processes, which align brain capillaries and pia, is particularly rich in AQP4. Several isoforms of AQP4 have been described; however, only some (AQP4a (M1), AQP4 c (M23), AQP4e, and AQP4ex) have been identified in the plasma membrane assemblies of astrocytes termed orthogonal arrays of particles (OAPs). Intracellular splicing isoforms (AQP4b, AQP4d, AQP4f, AQP4-Δ4) have been documented, and most of them are postulated to have a role in the cell surface distribution of the plasma membrane isoforms and in the formation of OAPs in murine and human astrocytes. Although OAPs have been proposed to play various roles in the functioning of astrocytes and CNS tissue as a whole, many of these still need to be described. OAPs are studied primarily from the perspective of understanding water permeability regulation through the plasma membrane and of their involvement in cell adhesion and in the dynamics of astrocytic processes. This review describes the cellular distribution of various AQP4 isoforms and their implications in OAP assembly, which is regulated by several intracellular and extracellular proteins.
42
Indonesia, Alfath Bagus Panuntun El Nur. "Education and Social Mobility For Orang Asli Papua." PCD Journal 9, no. 2 (April 5, 2022): 121–47. http://dx.doi.org/10.22146/pcd.v9i2.3313.
Full textAbstract:
Papuan human resources are complicated due to educational barriers that make it difficult for indigenous Papuans (OAP) to achieve upward social mobility. Many factors have contributed to these educational barriers, including poverty, conflict and war, a lack of teachers, and poor infrastructure. These obstacles should be solved through the main feature of the Special Autonomy Law (SAL), namely the "special autonomy fund". Although these funds have been rolled out in Papua since 2001 to address inequality and improve OAP's human resources, their conditions have not improved significantly. This qualitative study explored the experiences of Mappi and Puncak OAPs involved in education financed by the special autonomy fund through cooperation between the government and the university. The findings revealed the positive effect of SAL on reducing educational barriers and increasing social mobility for OAPs, but there are still some areas that needed to be improved. OAPs’ experience showed that formal education was the main determining factor to upward social mobility. This article also highlighted several areas for change, such as informal education support that needed to be improved; promoting equal development in both the coast and the highlands; increased community participation; and strengthening the political will. Recommendations are also offered.
43
Stump, Trevor A., Leigh Anne Nelson, Yifei Liu, Carrie R. Kriz, Courtney A. Iuppa, Lauren A. Diefenderfer, Shelby E. Lang, Ellie S. R. Elliot, and Roger W. Sommi. "The effects of concurrent oral paliperidone or risperidone use with paliperidone long-acting injection." Mental Health Clinician 11, no. 1 (January 1, 2021): 12–18. http://dx.doi.org/10.9740/mhc.2021.01.012.
Full textAbstract:
Abstract Introduction Dosing recommendations for paliperidone long-acting injectable antipsychotic (LAIA) do not include oral antipsychotic (OAP) overlap; however, OAPs are often given concurrently despite limited evidence describing both the risks and benefits of this practice. Methods A retrospective chart review was conducted in patients initiated on paliperidone palmitate (PP) during a psychiatric hospitalization to compare patients who received OAP overlap versus those who did not. The primary outcome is the proportion of patients who receive prescription claims for benztropine, a medication commonly prescribed for extrapyramidal symptoms, at the time of LAIA discontinuation and 6 months postdischarge. Secondary outcomes include prescription claims for beta blockers and diphenhydramine, number of psychiatric emergency visits and hospitalizations, length of stay of the index hospitalization, frequency of LAIA discontinuation and the time to LAIA discontinuation. Results There is a significant difference in the proportion of benztropine prescription claims in the OAP overlap group versus the no-overlap group at the time of LAIA discontinuation (30% vs 0%, P = .046) but not at 6 months postdischarge. There are also significant differences in the number of psychiatric emergency visits (0.7 vs 0.1, P = .02) and psychiatric hospitalizations (0.6 vs 0.1, P = .029) at the time of LAIA discontinuation. No other differences are observed in defined secondary outcomes. Discussion Patients who receive OAP overlap while receiving PP receive more benztropine and have more psychiatric emergency visits and hospitalizations than those treated without OAP. Larger studies with better control for confounding variables are needed to confirm these results.
44
Zafereo, Mark E., Rodney J. Taylor, and Kevin D. Pereira. "S248 – Supraglottoplasty for Laryngomalacia with Sleep Apnea." Otolaryngology–Head and Neck Surgery 139, no. 2_suppl (August 2008): P158. http://dx.doi.org/10.1016/j.otohns.2008.05.423.
Full textAbstract:
Objectives To determine if supraglottoplasty is effective in reversing abnormal respiratory parameters in children with laryngomalacia and obstructive sleep apnea. Methods 10 patients with laryngomalacia and obstructive sleep apnea as documented by polysomnography underwent supraglottoplasty at a tertiary referral children's hospital between 2005 and 2007. Retrospective data collection included age, findings on flexible and rigid endoscopy, type of procedure performed, and postoperative course. The postoperative polysomnographies were reviewed to identify changes in obstructive apnea index (OAI), obstructive apnea/hypopnea index (OAHI), respiratory disturbance index (RDI), and low arterial oxygen saturation (O2 nadir) after supraglottoplasty. Pre- and postoperative mean data were calculated, and comparisons were made with a Student's T-test. Results All 10 patients were successfully extubated following supraglottoplasty. There were no perioperative or postoperative complications, and no patient required a subsequent airway procedure. Each patient had a postoperative nocturnal polysomnography performed following supraglottoplasty at 11 weeks (range 2–29 weeks). Caregivers reported mild improvement (10%), significant improvement (70%), and complete resolution (20%) of stridor and nocturnal snoring at a follow-up visit 4 weeks after hospital discharge. Marked improvements were observed in OAI, OAHI, RDI and O2 nadir, all of which were statistically significant (p<0.05). Conclusions Polysomnography should be included in the initial evaluation of infants with laryngomalacia to rule out obstructive sleep apnea. Supraglottoplasty is an effective treatment for infants with laryngomalacia and obstructive sleep apnea. The significant benefits of the procedure outweigh the low morbidity. Improvement after surgery can be reliably confirmed by polysomnography.
45
O'Shea, Sebastian, Jonathan Crosier, James Dorsey, Louis Gallagher, Waldemar Schledewitz, Keith Bower, Oliver Schlenczek, et al. "Characterising optical array particle imaging probes: implications for small-ice-crystal observations." Atmospheric Measurement Techniques 14, no. 3 (March 9, 2021): 1917–39. http://dx.doi.org/10.5194/amt-14-1917-2021.
Full textAbstract:
Abstract. The cloud particle concentration, size, and shape data from optical array probes (OAPs) are routinely used to parameterise cloud properties and constrain remote sensing retrievals. This paper characterises the optical response of OAPs using a combination of modelling, laboratory, and field experiments. Significant uncertainties are found to exist with such probes for ice crystal measurements. We describe and test two independent methods to constrain a probe's sample volume that remove the most severely mis-sized particles: (1) greyscale image analysis and (2) co-location using stereoscopic imaging. These methods are tested using field measurements from three research flights in cirrus. For these cases, the new methodologies significantly improve agreement with a holographic imaging probe compared to conventional data-processing protocols, either removing or significantly reducing the concentration of small ice crystals (< 200 µm) in certain conditions. This work suggests that the observational evidence for a ubiquitous mode of small ice particles in ice clouds is likely due to a systematic instrument bias. Size distribution parameterisations based on OAP measurements need to be revisited using these improved methodologies.
46
Kirk, Johnathan P., and Gordon A. Cromley. "Assimilating Weather Data into a Digital Event Gazetteer of Airborne Parachute Operations during the French Indochina War." Weather, Climate, and Society 10, no. 1 (November 21, 2017): 19–34. http://dx.doi.org/10.1175/wcas-d-17-0016.1.
Full textAbstract:
Abstract Modern datasets cataloging historical events, known as digital event gazetteers, feature spatiotemporal data regarding events that enable analysis through parameters including location and other descriptive information of those events. Weather and climate data represent two dimensions of spatiotemporal information, which can enhance understanding of historical events. A recently published digital event gazetteer of airborne parachute operations [opérations aéroportées (OAPs)] during and prior to the French Indochina War, spanning from 1945 to 1954, represents an opportunity to associate discrete historical events with weather information. This study outlines a methodology for assimilating weather data into the construct of a digital event gazetteer and then demonstrates example analyses of how the weather and climate conditions in Indochina may relate to OAPs during the war. A synoptic classification, utilizing the self-organizing maps procedure, is performed using daily mean sea level pressure data from 1945 to 2010, from a twentieth-century reanalysis dataset, to characterize weather patterns over the Indochina Peninsula. Since observations are sparse during the years of the conflict, the resulting weather patterns are associated with modern precipitation observations in the area, as a representation of wet and dry patterns during the war. The appropriate daily weather pattern is then assigned to each OAP in order to investigate its relationship with the weather and climate patterns of Indochina, including the influence of monsoon seasons, and how the resulting precipitation patterns affected combat operations across the theater. Additionally, specific OAPs of various missions are analyzed to investigate how weather patterns may have affected operation planning during the French Indochina War.
47
Wicaksono, Wicaksono, Pudji Permadi, Utjok W. R. Siagian, and Tjokorde Walmiki Samadhi. "Very High Temperature Laboratory CO2 Injection." Modern Applied Science 11, no. 12 (November 20, 2017): 58. http://dx.doi.org/10.5539/mas.v11n12p58.
Full textAbstract:
Carbon dioxide (CO2) injection is the most promising technique to enhance the recovery of high gravity oil with the existing oil price situation. Even though, challenges still exist for thick and heterogeneous reservoirs at very high temperature. The problems faced in such reservoirs are low displacement efficiency and very high injection pressure requirement for a miscible displacement. The effort being done by researchers to overcome the situations is the use of silica nanoparticle as an agent to form CO2-silica nanoparticle foam. Currently, the related literature shows that CO2 miscible displacement is rarely performed at very high temperature and consequently no relevant effort has been made to investigate the stability of CO2-silica nanoparticle foam, while there are many oil reservoirs with temperature of higher than 250 oF. Therefore, related studies on such situations are needed. The present work consists of two stages. First, slimtube and coreflood experiments of CO2 injection are conducted at about 270 oF, respectively, to both determine the Minimum Miscibility Pressure (MMP) of the selected live oil system and the oil recovery. Secondly, CO2-silica nanoparticle foam stability in various brine salinity at such high temperature will be investigated and effectiveness of the selected stable foam will be tested through an oil displacement using native cores.In this paper, the results of both slimtube and coreflood experiments are first presented. A live paraffinic oil with 34 oAPI is used. The standard slimtube apparatus is employed. Stacked core composing of three native core plugs of different permeability ranging from 75 to 503 milidarcies are used to represent rock heterogeneity. At a temperature of 270 oF, MMP of the oil obtained from the slimtube experiment is 2960 psi, about 100 psi higher than that obtained from the coreflood experiment. The slimtube test gives oil recovery 94.2% and the coreflood as expected yields lower recovery, 84% of the initial oil in place. The importance of the tests is two folds that the MMP of the oil system is firmly known while the existing empirical correlations estimate the values ranging from 2718 to 5578 psi and a relatively low coreflood oil recovery suggests further investigation of stability of CO2-silica nanoparticle foam at that temperature in an attempt for enhancing the oil recovery.
48
Rubio, Jose M., Heidi Taipale, Christoph U. Correll, Antti Tanskanen, John M. Kane, and Jari Tiihonen. "Psychosis breakthrough on antipsychotic maintenance: results from a nationwide study." Psychological Medicine 50, no. 8 (June 13, 2019): 1356–67. http://dx.doi.org/10.1017/s0033291719001296.
Full textAbstract:
AbstractBackgroundThere is uncertainty about the incidence of breakthrough psychosis in treatment adherent patients, and the role that factors, such as cumulative antipsychotic exposure, play in this phenomenon.MethodsIn a nationwide cohort of individuals treated for schizophrenia-spectrum disorders in Finland between 1 January 1996 and 31 December 2015, ‘Breakthrough Psychosis on Antipsychotic Maintenance Medication’ (BAMM) was defined as hospitalization for psychosis despite ongoing continuous treatment with long-acting injectable antipsychotics (LAIs) or oral antipsychotics (OAPs) for ⩾8 weeks. Incidence rates, survival curves, and risk factors were presented.ResultsIn a cohort of 16 031 continuous LAI treatment episodes with virtually assured adherence [median duration = 441 days, interquartile range (IQR) = 155–1277], BAMM incidence was 31.5%. For 42 867 OAPs treatment episodes (median duration = 483 days, IQR = 167–1491), for whom adherence was modeled by the PRE2DUP method, BAMM incidence was 31.1%. Factors related to illness instability at treatment onset were associated with BAMM, although median time to BAMM was 291 days (IQR = 121–876) for LAIs and 344 days (IQR = 142–989) for OAPs, and 27.4% (N= 1386) of the BAMM events in the LAI, and 32.9% (N= 4378) in the OAP group occurred despite >1 year since last hospitalization at treatment onset. Cumulative antipsychotic exposure was not a consistent risk factor.ConclusionBAMM was relatively common even when adherence was confirmed with LAIs. Illness instability at treatment onset accounted for most cases, but relapse after years of continuous treatment was still prevalent. There was insufficient evidence to support causality between cumulative antipsychotic exposure and BAMM. Future research needs to address the role of symptom severity and neurobiology in BAMM.
49
Prami, Tuire, Houssem Khanfir, Pål Hasvold, Eeva Reissell, Juhani Airaksinen, and Ville Kytö. "Concomitant use of drugs known to cause interactions with oral antiplatelets—polypharmacy in acute coronary syndrome outpatients in Finland." European Journal of Clinical Pharmacology 76, no. 2 (November 26, 2019): 257–65. http://dx.doi.org/10.1007/s00228-019-02777-z.
Full textAbstract:
Abstract Purpose Use of oral antiplatelets (OAPs) is essential for preventing thrombotic events in patients with acute coronary syndrome (ACS). Effects of clopidogrel, prasugrel, and ticagrelor may be enhanced due to pharmacodynamic interactions, but as CYP substrates, they are prone to pharmacokinetic interactions too. The aim was to study polypharmacy in ACS patients following hospital discharge. Methods This observational drug utilization study linked patient-level data from nationwide registers. The study population consisted of adult ACS patients discharged from Finnish hospitals in 2009–2013. Logistic regression was used to model the probability of drug-drug interactions with odd ratios for predefined predictors such as age, gender, and ACS type. Results In the cohort of 54,416 ACS patients, 91% of those treated with OAP received clopidogrel. Of clopidogrel-treated patients, 12% purchased warfarin at least once while on clopidogrel treatment. Old age, male sex, ST-elevation myocardial infarction as index event, and a history of previous ACS events were associated with an increased risk of warfarin-OAP interaction (p < 0.001 for all). Ibuprofen, and serotonergic drugs tramadol, citalopram, and escitalopram were the next most common drugs causing pharmacodynamic interactions. In general, concomitant use of drugs known to cause pharmacokinetic interactions was rare, but both esomeprazole and omeprazole were prescribed in more than 6% of clopidogrel-treated patients. Conclusions Warfarin and ibuprofen were the most commonly used concomitant medications causing pharmacodynamic interactions and potentially increasing the risk of bleeding in OAP-treated patients. Esomeprazole and omeprazole were used in clopidogrel-treated patients although there are alternatives available for gastric protection.
50
Chen, Maxine, Jason Shepherd, Hollie Bailey, Jack Wright, and Heather M. Fitzgerald. "Analysis of Treatment Goals for Patients with Schizophrenia: A US Survey of Psychiatrists, Patients with SCZ and Caregivers." CNS Spectrums 26, no. 2 (April 2021): 158. http://dx.doi.org/10.1017/s1092852920002539.
Full textAbstract:
AbstractObjectivesObjectives for this survey are to determine similarities or differences in treatment goals reported by psychiatrists, patients with schizophrenia (SCZ) and caregivers in the US, as well as whether goals differed by patients currently on an oral antipsychotic (OAP) or long-acting injectable (LAI), and whether goals differed by age.MethodsThis was a real-world, cross-sectional survey of US psychiatrists, patients =18 years old diagnosed with SCZ, and caregivers. Data was collected using the Disease Specific Programme (DSP) methodology. Psychiatrists (n=120) completed detailed record forms for next 8 outpatients and 2 inpatients matching inclusion criteria. The same patients and their caregivers, if present, were invited by their psychiatrist to voluntarily complete a separate survey.ResultsResponses on treatment goals were collected from psychiatrists for all patients included in the analysis (n=1161), patients (n= 542) and caregivers (n=130). Among 3 top goals, psychiatrists, patients and caregivers concurred that “decrease in disease symptoms” is most important (63%, 64%, 68% respectively). For psychiatrists and caregivers, second was “decrease in hospitalization for relapse” (41%, and 38% respectively), whereas for patients, it was “thinking clearly” (47%). Of the 3 least important goals, psychiatrists, patients and caregivers agreed with “sexual problems” (59%, 43%, 44%, respectively) and “weight gain” (38%, 44%, 38%, respectively).When asked which goals were met by current medication, patients responded “decrease in disease symptoms” (68%) and “thinking clearly” (39%). However, caregivers responded “thinking clearly” (30%) was not met by current medication. Caregivers most important goals, “decrease in disease symptom” (70%) and “decrease in hospitalization for relapse” (41%), were met. Additional analyses of patients on OAPs and LAIs, did not show differences in goals. However, “decrease in disease symptoms” was numerically more important for patients on LAIs vs OAPs according to psychiatrists (68% vs 62%) and caregivers (77% vs 70% respectively). Caregivers responded “decrease in hospitalization for relapse” was met for 63% patients currently on an LAI and 35% OAP. No major differences in treatment goals were observed by patient age (18–35 vs 36–65 vs >65 years).DiscussionThere is consensus among US psychiatrists, patients and caregivers on the most important treatment goal “decrease in disease symptoms”, regardless of patients’ current medication or age. For patients, “thinking more clearly” was second, compared with “decrease in hospitalization due to relapse”, for psychiatrists and caregivers. All agreed that least important treatment goals, related to AEs, were “weight gain” and “sexual problems”. More caregivers agreed “decrease in hospitalization for relapse” was met by patients on LAIs vs OAPs. These findings may help with discussions between psychiatrists, patients and caregivers.FundingLundbeck LLC and Otsuka Pharmaceutical Development & Commercialization, Inc.