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Thida, Win, Than Kyae Aye, Htun Naing Tin, and Kyaw Naing Kyaw. "Long Term Measurements of Radon Concentrations in Some Cheroot Samples." International Journal of Trend in Scientific Research and Development 3, no. 5 (2019): 1802–4. https://doi.org/10.5281/zenodo.3591501.
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Radon is the biggest contributor to natural and radiation in the environment and causes long term health concern. The link between tobacco, cigarette smoke and cancer has long been established. Smokers are ten times at greater risk of developing lung cancer than that of non smokers. In this work, the radioactive radon concentrations of some cheroot samples in Myanmar were measured using SSNTDs technique and long term measurements were carried out for period of 100 days. According to the detection of alpha tracks, alpha track density and radon concentrations were carried out. And then annual effective dose of radiation in the corresponding samples were calculated. Thida Win | Aye Than Kyae | Tin Htun Naing | Kyaw Kyaw Naing "Long-Term Measurements of Radon Concentrations in Some Cheroot Samples" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd26788.pdf
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Ginkut, Natalia V. "Byzantine Fourteenth-Century Glazed Vessels Featuring Monograms Excavated in Cherson and the Castle of Cembalo." Античная древность и средние века 48 (2020): 225–53. http://dx.doi.org/10.15826/adsv.2020.48.015.
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This paper addresses the Byzantine vessels featuring monograms excavated in Cherson and in Cembalo, and their interpretation and significance for the life of the Greek population of the south-western Crimea. So far, archaeological researches discovered 15 vessels made in Byzantium, which showed monograms of the life of saints (“George,” “Michael,” and “Prodromos”), the family name “Palaiologos,” and also code letters “A” (“relic”) and “K.” These vessels were containers for holy water, and in a few cases, plausibly, for myrrh. These vessels were delivered to Cherson and Cembalo as gifts or eulogiai from Constantinople (?), as a part of ideological propaganda. The comparative archaeometric study of the three samples from Cembalo castle in a lab of the University of Lyon revealed one vessel’s similarity with the products of a fourteenth-century pottery workshop discovered in the vicinity of Istanbul. Although two samples more belong to a group different from the said workshop’s products, they still show similar technological parameters. The chronology of the vessels in question lays within the 1320s–1350s in Cherson and from the second half of the fourteenth to the early fifteenth century in Cembalo.
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Bazir, Hanaâ, Najwa Hassou, Fatiha El Mellouli, Hasnae Zekhnini, Saliha Najib, and Moulay Mustapha Ennaji. "Hepatitis A and E Viruses in Mussels from Cherrat Estuary in Morocco: Detection by Real-Time Reverse Transcription PCR Analysis." Advances in Virology 2022 (November 28, 2022): 1–7. http://dx.doi.org/10.1155/2022/8066356.
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The aim of the present study was to evaluate hepatitis A virus (HAV) and hepatitis E virus (HEV) contamination in mussels (Mytilus galloprovincialis) from Cherrat estuary (Moroccan Atlantic Coast), Morocco. In total, 52 samples (n = 12 mussels/each) were collected at four sites in the estuary, monthly, between March 2019 and March 2020. HAV and HEV were detected by real-time reverse transcription polymerase chain reaction (RT-PCR) according to the ISO/TS 15216 method. HAV was detected in 46.15% of analyzed samples. Conversely, HEV was not detected in any sample. Moreover, the HAV detection rate was significantly associated with seasonal rainfall variations. This qualitative study on HAV and HEV contamination highlights the interest of studying mussel samples from wild areas. As HAV presence in mussels represents a potential health risk, viral contamination surveillance of mussels is necessary to protect consumers. HAV shellfish contamination must be monitored at Cherrat estuary because of the role played by shellfish as HAV reservoirs and/or vehicles in fecal-oral HAV transmission.
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Alekseienko, Nikolay A. ,., and Anna V. Antipenko. "Issuing Cast Lead Coins in Byzantine Cherson: A Local Phenomenon or a Technological “Flaw”?" Materials in Archaeology, History and Ethnography of Tauria, no. XXVI (2021): 447–58. http://dx.doi.org/10.37279/2413-189x.2021.26.447-458.
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Although the aspects of the production of Byzantine-Cherson cast coins and the technological nuances of their manufacture have been repeatedly studied in Russian scholarship, every time there appeared various hypotheses and assumptions, mostly remain highly debatable so far. For a long time, the lack or difficulties of access to the special equipment allowing the one to determine coin alloys allowed the researchers to draw conclusions about the coin material only against the background of some definitions from the scholarship and visual indicators. Among the disputable aspects is the casting of Cherson-Byzantine lead coins. In this connection, we have studied 30 specimens of coins by laboratory research of the alloy composition by X-ray fluorescent analysis. The samples selected for examination visually suggested a high content of lead. It has been found out that in the samples examined have similar elemental composition of coin alloy, lead with additions of arsenic. It is possible that, in the Byzantine Period, the Taurica received lead from the mines located in the Caucasus area, which were typical of a high content of arsenic. The most part of the of samples (27 specimens) contained more than 2/3 of lead; the alloy of three coins contained similar proportions of copper and lead. Taking the said results into account, we can suppose that the “almost pure” lead coins most likely were a specific kind of technological “flaw” in the casting in Cherson. It is still possible that, in the sorting of the ready-made coins, the specimens not corresponding to the standard samples and having casting defects (partial casting of the mould or lead casts) were withdrawn and returned to remaking. This interpretation explains why the so-called “lead” coins are relatively rare: they occurred mostly in the coinages from the age of Basil I and Leo VI, though in some series they were unique or unknown.
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Bilal, Hazrat, Muhammad Alam, Naqeeb Ullah Khattak, Muhammad Yasir, Muhammad Suliman, and Kiramat Ali. "Physical Properties of Different Brands of Cement Manufactured in KPK, Pakistan: A Case Study." Pakistan Journal of Engineering and Technology 5, no. 4 (2022): 63–67. http://dx.doi.org/10.51846/vol5iss4pp63-67.
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One of the key elements affecting structural concrete's strength and longevity is the cement's quality. In Pakistan, large amounts of cement are utilized in construction projects. This study appraised some physical properties of five brands of Portland cement bought from cement industries in KPK. Cement brands are investigated, including Cherat cement, Askary cement, Luckey cement, Kohat +, and Bestway cement. The composition of the cement has been recorded from the cement bags. Each initial setting time, normal consistency, final setting time, fineness, and compressive strength cement samples (collected as bags from the market) have been tested in the laboratory at three days, seven days, 14 days, and 28 days per ASTM standards. Amongst these various cement brands in KPK, we aim to investigate the best cement brands taking into consideration the above all physical test and then test these brands after three months. Taking time as a factor, the best cement quality is to be found. According to the fineness of cement, Cherat cement is found to be the best amongst all five brands of cement when tested initially, while lucky and Kohat were the least in fineness properties. Consistency tests were performed for all brands of fresh types of cement, and Cherat and Kohat have more consistency, while Askary has the least consistency. Initial and Final setting time tests were performed for all brands, and Cherat cement was found to have the more initial and final setting time, while Kohat and Askary had the least setting time. In the case of the compressive strength test, Cherat cement was found to be the greater strength, while lucky had the least compressive strength. For seven days curing. For 28 days curing Cherat cement was the best one having greater strength, while Askary had the least strength among all. All the cement brands were tested the same way after three months of age, which shows that all five brands crossed the ranges for each test. Still, it has been observed that the decrease in the fineness is small for Cherat compared to all other brands while in case of compressive strength, the decrease in Cherat is greater than all other brands.
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Schürch, Benjamin, Stefan Wettengl, Simon Fröhle, Nicholas Conard, and Patrick Schmidt. "The origin of chert in the Aurignacian of Vogelherd Cave investigated by infrared spectroscopy." PLOS ONE 17, no. 8 (2022): e0272988. http://dx.doi.org/10.1371/journal.pone.0272988.
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The analyses of raw material provenance offers the possibility of tracing short and long-distance raw material transport. So far, most studies of raw material of flint and chert in Europe have been based on macroscopic analyses. We apply infrared spectroscopy to Aurignacian assemblages from Vogelherd cave and to the Magdalenian site Randecker Maar in southwestern Germany. We compare raw material samples from three chert-bearing areas in Germany with archaeological samples from Vogelherd. Our results show that infrared spectroscopy can distinguish between different raw materials. Our archaeological samples from Vogelherd correspond to the sampled geological cherts in terms of their spectral signature. Our comparison of reference samples and archaeological samples highlights problems in commonly used macroscopic identifications of chert raw materials.
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Bazir, Hanaâ, Najwa Hassou, Fatiha El Mellouli, Hasnae Zekhnini, and Moulay Mustapha Ennaji. "Spatial-temporal assessment of Norovirus contamination in mussels from Cherrat estuary, Morocco, by real-time Reverse Transcription-Polymerase Chain Reaction." Journal of Applied and Natural Science 15, no. 1 (2023): 155–61. http://dx.doi.org/10.31018/jans.v15i1.4176.
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Mussels filter large amounts of water to extract nutrients; therefore, they can concentrate and accumulate in their tissues infectious agents, and vectors of enteric diseases. The aim of this study was to assess mussel contamination by Norovirus genogroups I and II in the Cherrat estuary to determine the public health risk linked to their consumption. Mussels (Mytilus galloprovincialis) were collected (n=52 samples; 12 mussels/sample) at four sites (S1 and S2 located on the right rocky bank / S3 and S4, located on the rocky left bank) in the Cherrat estuary (Casa-Settat region), Morocco, during 13 months, from March 2019 to March 2020. Norovirus was detected and quantified by real-time Reverse Transcription-Polymerase Chain Reaction (RT-PCR). Norovirus genogroups I and II were detected in 17.30% and 94.23% of mussel samples, respectively. Contamination by Norovirus (genogroups I and II) was not correlated with seasonal factors (month and rainfall), and Norovirus prevalence was comparable among the four sampling sites. Consumption of raw or undercooked mussels contaminated with Norovirus can cause gastroenteritis, which represents a potential risk to human health. The present study would be helpful to control and manage the potential risk to the public health of the Moroccan population due to the degradation of water quality continuously impacted by runoff, the urban wastewater treatment system malfunctions, and overflows from nearby sewage systems.
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Régis, Braucher, Hidy Alan J., Matmon Ari, Bourlès Didier, Aumaître Georges, and Keddadouche Karim. "Towards successful cleaning of chert samples for improved 10Be and 26Al measurements." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 456 (October 2019): 257–63. http://dx.doi.org/10.1016/j.nimb.2019.03.030.
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Astakhova, I. "Documentary and material scientific heritage of geologists in the A. A. Chernov Geological Museum." Vestnik of geosciences, no. 5 (June 30, 2023): 48–50. http://dx.doi.org/10.19110/2712-7761-2023-5-48-50.
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Together with samples of rocks and minerals, documentary materials on the history of the geological study of the European North of Russia, cartographic material, and personal funds of geologists are systematized at the Geological Museum named after A. A. Chernov. The museum holds memorial offices of Professor A. A. Chernov and Academician N. P. Yushkin. The historical and archival fund has 16 personal funds with 505 storage units. Letters, notebooks, albums, personal documents, separate prints of articles, awards, diplomas, and letters of acknowledgements form museum funds. These materials allow creating exhibitions and depicting development of science and geological knowledge.
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Beznosova, T. M., and V. A. Matveev. "Stratotypic section of the Wenlockian Voyvyv horizon (Western slope of the Subpolar Urals)." LITHOSPHERE (Russia) 24, no. 1 (2024): 81–97. http://dx.doi.org/10.24930/1681-9004-2024-24-1-81-97.
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Research subject. The paper presents the results of a study into the carbonate-terrigenous section of 197.8 m-thick Wenlockian section in the Shchugor River basin, which is proposed as the stratotype of the regional horizon. Materials and methods. The study was based on numerous samples from Lower Silurian deposits collected by the authors in different years during fieldwork on the Western slope of the Circumpolar Urals and the Chernov and Chernyshev uplifts, as well as the biostratigraphic, paleontological, lithological, and C-isotopic data obtained during these works. Results. The obtained data allowed revising some of the established ideas about the structure of the Lower Silurian section and the position of the boundary level between the Llandoverian and Wenlockian in the Subpolar Urals and to identify a new regional subdivision with the name “Voyvyv”. The traced formation conditions of shallow carbonate sediments of the Voyvyv horizon and the consistent change of zonal taxa of marine fauna in the stratotype section indicate similarity with coeval strata on the Chernov and Chernyshev uplifts and Dolgy Island. Conclusions. The results of the study of Wenlockian Voyvyv deposits in the Timan-North Urals region showed that the section in the Shchugor River basin in outcrop 10c can be considered the most informative in the Northern Urals region in terms of exposure degree, established stratigraphic completeness, and preservation of macro- and microfauna.
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Olivares, Maitane, Andoni Tarriño, Xabier Murelaga, Juan Ignacio Baceta, Kepa Castro, and Nestor Etxebarria. "Non-destructive spectrometry methods to study the distribution of archaeological and geological chert samples." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 73, no. 3 (2009): 492–97. http://dx.doi.org/10.1016/j.saa.2008.12.036.
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Ivanov, Alexander, Konstantin Savinov, and Roman Eremenko. "Impact of Conversion From the Use of Binary Artificial Neurons to the Use of Ternary Neurons With the Combined Applying of Five Classical Statistical Criteria for Normality or Uniformity Hypothesis Testing for Small Samples Distributions." Вестник Пермского университета. Математика. Механика. Информатика, no. 3(58) (2022): 59–67. http://dx.doi.org/10.17072/1993-0550-2022-3-59-67.
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The work purpose is to show the advantages of moving from ordinary binary neurons to more complex neurons with ternary output quantization. As an example, a neural network combination of five classical statistical criteria is considered: Geary (1935), David-Hartley-Pearson (1954), Shapiro-Wilk (1965), Maximum deviation from the center (1965), Ali-Chergo-Revis (1992). A forecast of combining these criteria with others is given, built with confidence probability is equal to 0.99. The binary artificial neurons using will require the use of 280 statistical criteria. The conversion to the artificial neurons using with ternary quantizers should reduce the neurons number to 9 for small samples of 16 experiments. An exponential decreasing of the necessary neurons number is seen.
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Qureshi, Kamil Ahmed, Hamid Hussain, Afsar Ali Shah, Ishaque Ali Meerani, Shah Fahad, and Abdul Basit. "Hydrocarbon Source and Reservoir Rock Potential of the Paleocene Hangu Formation in the Himalayan Foreland Basin, North West Pakistan: Insight from Geochemical and Diagenetic Study." Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences 62, no. 3 (2019): 157–66. http://dx.doi.org/10.52763/pjsir.phys.sci.62.3.2019.157.166.
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The detail study of the Paleocene Hangu Formation consisting of sandstone, carbonaceous shale, coal, and laterite has been carried out for its source and reservoir rock potential in the Salt Range, Surghar Range, and Attock-Cherat Ranges. The TOC values of the shales range from 0.33-11.19 (2.97 wt. %) and are characterized as good to very good quality source rock except the samples from Attock-Cherat Ranges. Similarly, the free (S1) and cracked hydrocarbons (S2) amount are very small suggesting Hangu Formation as a poor source rock for free and cracked hydrocarbons except the samples from the Lumshiwal Nala. The generative potential, type of kerogen and thermal maturity calculated on the basis of TOC, S1, S2, HI, PI and Tmax all characterized Hangu Formation as fair to excellent gas or oil source, type III and mixed type III/II kerogen and immature source rock. The Hangu Formation sandstone is brownish to yellowish brown, fine to coarse grained, medium to thick bedded and massive in places. The major diagenetic changes observed in a sandstone of the Hangu Formation are; compaction, cementation, replacement and grain fracturing. The effect of mechanical compaction is more evident than that of chemical compaction. Grain contact ranges from pointed to long through sutured. The type of cement present includes silica-cement, calcite-cement, dolomite-cement, and iron-oxide cement. Silica-cement is present as both overgrowth and pore-filling cement. Clay rim is present around few grains. The process of early calcite cementation, mechanical compaction, silica, and iron oxide cementation destroys the reservoir properties of the Hangu Formation sandstone. There is no visible porosity observed except the dissolution of few grains at their margins. However, during the process of uplifting such porosity usually filled by the iron- oxide cementation. Hence, Hangu Formation is an immature source rock with a poor reservoir potential.
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Sitarz, M., P. Wyszomirski, B. Handke, and P. Jeleń. "Moganite in selected Polish chert samples: The evidence from MIR, Raman and X-ray studies." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 122 (March 2014): 55–58. http://dx.doi.org/10.1016/j.saa.2013.11.039.
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Pal-Val, Pavel, Olena Vatazhuk, Andriy Ostapovets, Lubomír Král, and Jan Pinc. "Thermoactivated Dislocation Motion in Rolled and Extruded Magnesium: Data of the Low-Temperature Acoustic Experiment." Metals 11, no. 10 (2021): 1647. http://dx.doi.org/10.3390/met11101647.
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Acoustic properties (logarithmic decrement and dynamic Young’s modulus) of commercial grade magnesium have been measured in the temperature range 51–310 K. Two types of magnesium samples have been studied: polycrystalline magnesium rolled at room temperature and subjected to hot extrusion. It is shown that the amplitude dependences of the acoustic properties are due to the thermally activated breakaway of dislocations from weak pinning centers. Within the framework of the Indenbom-Chernov theory of thermally activated dislocation hysteresis, the binding energy of the interaction between dislocations and defects was estimated. Furthermore, dependences of the activation energy and activation volume on the applied stress were obtained in the microplastic region. The temperature dependences of the dynamic Young’s modulus are obtained in the amplitude independent region in the temperature range of 51–310 K. Functional form of the Young’s modulus temperature dependences corresponds to the classical concepts of the effect of thermal excitation of electrons and phonons on the elastic properties of crystals.
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Olivares, Maitane, Asier Vallejo, Mireia Irazola, et al. "Optimisation of focused ultrasound extraction (FUSE) and microwave-assisted extraction (MAE) of hydrocarbons in geological chert samples." Talanta 83, no. 2 (2010): 605–12. http://dx.doi.org/10.1016/j.talanta.2010.10.004.
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Rychkov, B. A., I. V. Goncharova, and P. M. Rezin. "ABOUT THE YIELD PLATEAU UNDER SIGN-VARIABLE LOADING." PNRPU Mechanics Bulletin, no. 3 (December 15, 2021): 141–53. http://dx.doi.org/10.15593/perm.mech/2021.3.13.
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During tension of samples of low-carbon steels and some other plastic materials, the sharp yield point and the yield plateau are fixed on the deformation diagram. In this case, Chernov-Luders bands appear on the surface of the sample in the local section, which then propagate along the tension axis. The physical nature of the sharp yield point is established: the drop in the load after reaching the (upper) yield limit occurs as a result of dislocations being an extraction out of the cloud of the embedded atoms and vacancies (Cottrell's cloud). At the occurrence of the sharp yield point , the plastic strain is limited to a small area. When the sample deformation increases, the plasticity zone (the yield plateau is marked on the diagram at this time) expands, and the stress-strain state in this zone becomes almost homogeneous, if we do not consider its boundary with the elastic region. At the end of the yield plateau, the entire sample experiences a uniform plastic deformation, excluding its ends (galtels). From this point on, the strain diagram shows the of material hardening; presumably, this hardening occurred from the very beginning, but was hidden under the yield plateau. This is evidenced by the resulting strain-induced anisotropy. After unloading the sample, when the plastic strain front (in the form of Chernov-Luders bands) has not yet passed through the entire sample, and the Bauschinger's effect is observed with the subsequent change in the stress sign. The fact that after the occurrence of the sharp yield point , the plastic strain is not localized in a certain volume, similar to what occurs during the neck formation, but spreads along the sample, serves as proof of the material hardening due to plastic deformation immediately after the load falls. Therefore, if the plastically deformable part of the sample did not have a hardening of the material due to the plastic strain growth, it would not be able to spread to the elastic part of the sample. This paper presents the experimental data of the sign-variable torsion of the thin-walled tubular samples of steel 45 in the annealed state. The deformation atdiagram of the occurrence and development of the yield plateau in distinct sections along the length of the test sample is obtained. The material hardening diagram hidden under the yield plateau is reconstructed using the well-known Masing's principle.
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Latif, Khalid, Muhammad Hanif, Syed Anjum Shah, et al. "Source rock potential assessment of the Paleocene coal and coaly shale in the Attock-Cherat Range of Pakistan." Journal of Petroleum Exploration and Production Technology 11, no. 6 (2021): 2299–313. http://dx.doi.org/10.1007/s13202-021-01172-8.
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AbstractIn this study the hydrocarbon generation potential of the coal and coaly shale samples collected from coal mines in Attock-Cherat Range of Pakistan is optically and analytically evaluated. These samples, representing the Paleocene Hangu Formation, are analyzed across a range of thermal maturity stages to understand their hydrocarbon generation potential. The visual examination of maceral type and values of vitrinite reflectance have been considered while interpreting the geochemical results for the coal and associated sediments from the Paleocene Hangu Formation. The maceral group is dominated by vitrinite, mainly collodetrinite, followed by inertinite and liptinite, and suggests Type III kerogen for the samples. The geochemical parameters suggest that the samples are post mature, however, the vitrinite reflectance measurements show late mature conditions for a gas-prone generation. The overall petrographical and geochemical data suggest that the coal and coaly shale appear to occupy the gas window and fall in the dry gas zone. Based on the maceral types and Rock–Eval data, an anoxic to terrestrial environment is inferred for the deposition of the coal and associated sediments. The vitrinite reflectance, Rock–Eval pyrolysis, and the type and frequency of macerals show that the coal is of good quality, i.e., medium to high volatile bituminous and hard brown coal, mature, and is lying in the gas window. Oxygen index is continuously low throughout the analyzed interval, which further supports that the coal is of good quality.
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Tzibulsky, Mark, and Vladimir Frid. "The Comminution of Chert Gravel by Microwave Irradiation." Resources 13, no. 5 (2024): 63. http://dx.doi.org/10.3390/resources13050063.
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Chert, a by-product rock of sand quarrying, has historically posed economic challenges for aggregate production, resulting in significant “waste” accumulation in quarries. Our study investigates the effect of microwave irradiation on the mechanical properties of chert gravel, a mineralogically homogenous material composed of fine quartz grains. The results, which demonstrate that increased irradiation time leads to a substantial decrease in chert gravel strength (by a factor of 4–6 for 2.5 min of irradiation), underscore the potential impact of this research on comminution processes. With quenching altering the fractional content of the samples after the crushing test, reducing the Gravel-to-Sand ratio, this study is driven by the promising potential of crushed chert gravel as a pivotal aggregate within the concrete and asphalt industries, offering a practical solution to their material needs. The urgent need to rehabilitate previously utilized quarry areas, offering an environmentally beneficial solution for which we all should be responsible, motivated the present study.
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Solomatin, V. M., and E. V. Spirin. "Impact of radioactive discharges of Siberian Chemical Plant (SCP) and Pilot-demonstration energy complex (PDEC) on aquatic biota inhabiting in the SCP 30-km zone." "Radiation and Risk" Bulletin of the National Radiation and Epidemiological Registry 31, no. 3 (2022): 26–36. http://dx.doi.org/10.21870/0131-3878-2022-31-3-26-36.
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Radiation doses to aquatic biota exposed to Siberian Chemical Plant (SCP, Tomsk) radioactive discharges, and Pilot-demonstration energy complex (PDEC) forecasting radiation doses from designed radioactive discharges were estimated. Doses to the biota in the habitat in the existing radiation situation were assessed with the use of measurements of water and bottom sediments samples collected during environmental monitoring of airborne radioactivity in 2017. Designed radioactivity discharges were assumed from normally operated PDEC modules for fabrication and refabrication and fuel reprocessing and reactor BREST-OD-300. It was found that the esti-mated highest radiation doses to biota were: for freshwater mammals – 24 μGy/day, it is 40 times below the reference levels; for fish – 7 μGy/day, it is 140 times below reference levels; for aquatic plants and mollusks – 1.2 μGy/day, it is about 10000 times below the reference levels. Anticipated radiation doses to the aquatic biota exposed to radiation discharged by PDEC were formed in the Lake Chernoe (Black Lake). The highest doses to fresh water mammals, fish and birds are 0.3 μGy/day, for aquatic plants and mollusks – 0.05 μGy/day. The main contributor to anticipated radiation doses to aquatic biota and birds is tritium, 3H.
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Petukhova, Elena A. "The Era of Joy. Advertising Poster of the 1860s-1890s as a Continuation of the Laughter Culture of the European Middle Ages." Scientific and analytical journal Burganov House. The space of culture 18, no. 5 (2022): 29–40. http://dx.doi.org/10.36340/2071-6818-2022-18-5-29-40.
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This article aims to study the influence of urban advertising on the formation of urban society’s positive mood in France at the turn of the 20th century. The focus is on the heyday period of circulation graphics, which was the result, firstly, of the improvement of printing techniques by the middle of the 19th century and the appearance of lithography, which made it possible to repeatedly replicate advertising samples. Secondly, it was the result of the intensive increase in trade, industrial production and the number of product consumers, for whose attention manufacturers competed. In addition, by the 1890s, a generation of advertising masters had formed, in particular, the poster masters who skillfully used the features of the new creative form and attracted the attention of art critics. This refers to the era of Jules Cheret, Henri de Toulouse-Lautrec, Eugene Grasset, Adolphe Villette, Alphonse Mucha and others. An important aspect of this study is the research of the connection between the advertising poster of the Art Nouveau era and the laughter culture, which, according to M.Bakhtin, made a key contribution to the formation of the modern society’s thinking, as well as the concepts of the grotesque and the comic in the interpretation of the Russian writer and philosopher and Charles Baudelaire, a French poet and publicist. Consideration of poster communication from the standpoint of Bakhtin's theory is an original method. The artistic basis of this study is the poster heritage of artist Jules Cheret, the leading master of European printed advertising graphics of the second half of the 19th century. The concept approbation is carried out on the material of La Plume literary magazine, namely, issue No.110 of December 1893, which was entirely devoted to the art of the advertising poster. This article discusses six critical essays on Jules Cheret’s creative work. Their authors are E.Mendron, K.Huysmans, F.Champsaur, Roger Marx, Ivanhoe Rambosson, Raoul Serta. All translations of text fragments are made by the author of this article.
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Al-Sheraefy, Ruaa, Falah Ahmed, and Mohamed Alrashedi. "Geochemistry, Depositional Environment, and Provenance of the Cretaceous Radiolarian Chert in Northeastern Kurdistan, Iraq." Iraqi Geological Journal 55, no. 2F (2022): 43–59. http://dx.doi.org/10.46717/igj.55.2f.3ms-2022-12-18.
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The radiolarian chert rocks are one of the most important indications of the existence of ophiolites because they are a source of silica supply. These rocks have been studied to refute and reject the idea that ophiolites do not existed. The Si/(Si+Al+Fe+Ca) ratio in the radiolarian chert indicates that the silica is of biogenic origin and adds SiO2 from the shale fraction through diagenetic processes. The high values of Fe2O3 content indicate the hydrothermal effect during precipitation. This effect is controlled by the distance between the sediments and the mid-oceanic ridge or sea floor metamorphism. The phosphorus could be a direct result of volcanic activity associated with ophiolitic rocks, whereas, the negative correlation coefficient of phosphorous with calcium (r = -0.53) supports the idea that the source of phosphorous is volcanic activity that is not related to the carbonate fluorapatite mineral. REEs shows a basic difference as a positive cerium anomaly in section Q2 and a negative cerium anomaly in section Q1. The Al-Fe-Mn diagram shows that all samples fall into the field I non-hydrothermal zone, but in the SiO2 vs Al2O3 diagram the samples of the Q1 section fall into the hydrothermal field, and samples of the Q2 section fall into the non-hydrothermal field. The input materials in Qulqula radiolarian chert come from terrigenous sediments in both sections. On the other hand, the Al/(Al+Fe+Mn) ratio range, (between 0.61 to 0.70), is very close to the average shale composite value, (0.6.19), which may reflect the contribution from continental and non-hydrothermal sediments, while the lower values of this ratio reflect hydrothermal source input. The MnO2 /TiO2 ratios ranged between 0.06 to 2.37 in section Q1 which represents typical characteristics of the deep ocean, trenches, and basaltic plateau sediments.
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Kanapyanova, A. N. "Additions to the list of insects of the Dzhungar Alatau State National Natural Park based on the results of work for 2021." Kazakhstan zoological bulletin 2, no. 2 (2021): 49–52. http://dx.doi.org/10.54944/kzbld703wu91.
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Zhetysu Alatau is one of the richest regions of Kazakhstan in terms of animal species diversity, second only to Altai. Thanks to the favorable combination of various landscapes found here, they can be used for scientific, educational, environmental, educational, cultural and recreational purposes. Presumably, up to five thousand species of insects can live in the entire mountain system, so additional scientific research is needed in the field of inventory. In 2021, for this purpose, field trips were organized to the territory of the Zhongar Alatau Natural Park. Explored territories - Sarkan branch, Baskan, Topolevka, Amanbokter forestry; Chernov, Lepsi forestry of the Lepsinsky branch. To collect initial materials, i.e., photos, videos, samples for collecting, methods of visual examination of large insect species, mowing with an entomological net, and catching by light were used. Scientific reference literature was used to identify insects. As a result, 8 new species were included in the list of insects living in the park. Thus, the taxonomic list is 651 species belonging to 67 families and 11 orders. Of these, 4 species – Coleoptera, 3 species - Lepidoptera, 1 species – Hymenoptera orders. The article contains additions to the list of invertebrates of 2021 inhabiting the territory of the Dzhungarskiy Alatau SNPP.
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Namen, Abay, Radu Iovita, Klaus G. Nickel, Aristeidis Varis, Zhaken Taimagambetov, and Patrick Schmidt. "Mechanical properties of lithic raw materials from Kazakhstan: Comparing chert, shale, and porphyry." PLOS ONE 17, no. 4 (2022): e0265640. http://dx.doi.org/10.1371/journal.pone.0265640.
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The study of lithic raw material quality has become one of the major interpretive tools to investigate the raw material selection behaviour and its influence to the knapping technology. In order to make objective assessments of raw material quality, we need to measure their mechanical properties (e.g., fracture resistance, hardness, modulus of elasticity). However, such comprehensive investigations are lacking for the Palaeolithic of Kazakhstan. In this work, we investigate geological and archaeological lithic raw material samples of chert, porphyry, and shale collected from the Inner Asian Mountain Corridor (henceforth IAMC). Selected samples of aforementioned rocks were tested by means of Vickers and Knoop indentation methods to determine the main aspect of their mechanical properties: their indentation fracture resistance (a value closely related to fracture toughness). These tests were complemented by traditional petrographic studies to characterise the mineralogical composition and evaluate the level of impurities that could have potentially affected the mechanical properties. The results show that materials, such as porphyry possess fracture toughness values that can be compared to those of chert. Previously, porphyry was thought to be of lower quality due to the anisotropic composition and coarse feldspar and quartz phenocrysts embedded in a silica rich matrix. However, our analysis suggests that different raw materials are not different in terms of indentation fracture resistance. This work also offers first insight into the quality of archaeological porphyry that was utilised as a primary raw material at various Upper Palaeolithic sites in the Inner Asian Mountain Corridor from 47–21 ka cal BP.
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BOZKURT, ERDIN, BRIAN K. HOLDSWORTH, and ALI KOÇYIGˇIT. "Implications of Jurassic chert identified in the Tokat Complex, northern Turkey." Geological Magazine 134, no. 1 (1997): 91–97. http://dx.doi.org/10.1017/s0016756897006419.
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The Tokat Complex is a strongly deformed tectono-sedimentary mixture of low-grade metamorphic rocks with abundant recrystallized limestone and relatively rare serpentinite and radiolarian chert in blocks of variable size. Samples from the radiolarian chert blocks, found in highly crushed zones, each of which corresponds to a thrust sheet within an imbricate thrust zone, have yielded a Tithonian fossil assemblage. They are interpreted as tectonic inclusions emplaced within the Tokat Complex after its main post-early Permian–pre-Liassic metamorphism, and were derived from the rifting and opening of a Neotethyan ocean. The presence of Tithonian blocks within low-grade metamorphic rocks of the Tokat Complex shows that Tethys ocean was in existence in this region by latest Jurassic time. We also suggest that the presence of ophiolitic slices imbricated with the Pontide basement, Tokat Complex, explains the swarm of North Anatolian Fault Zone (NAFZ) splays in this region where the NAFZ likely followed a major pre-existing crustal weakness.
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Fedyukov, Vladimir I., Vasilii Yu Chernov, Maria S. Chernova, and Olga V. Tsoy. "Resonance Acoustic and Colorimetric Characteristics of Wood in Old Structures." Lesnoy Zhurnal (Forestry Journal), no. 6 (December 10, 2022): 164–77. http://dx.doi.org/10.37482/0536-1036-2022-6-164-177.
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The reserves of resonance wood in the forests of the planet are limited, and in many countries they are completely absent, since it is formed only under certain habitat conditions in some trees with genetically determined properties. Therefore, the investigation of correlation between acoustic and colorimetric parameters of coniferous wood retreads has scientific and practical importance for the development of non-destructive methods of resonance material identification in the elements of old structures to reveal additional sources of raw materials. The article presents the results of complex dendro-acoustic and colorimetric studies of spruce and pine wood. The RGB levels for seasoned wood in the additive color model were found to be on average 12 % lower than those for recently harvested wood. The analysis showed that the interrelation of RGB levels with acoustic constant (K) is weak (r2 < 0.3) for all groups of seasoned wood samples. It was also found out that 39 % of the spruce samples and 23 % of the pine sapwood samples selected from the seasoned wood can be attributed to resonance wood, since their K ≥ 12 m4/kgs. Thus, old wooden structures made of spruce wood and pine sapwood to be slated for destruction due to the long term operation are of great practical interest as a source for producing resonance wood with unique dendro-acoustic properties. It was found that within the same wood species or part of a tree (sapwood, heartwood), the color remains constant, and only the tone varies. Although the results of the study of wood colorimetric properties and acoustic constant did not show a high level of correlation, the research in this area is still relevant. This result may be due to the imperfection of the color determination technique, namely the need to consider the different number and parameters of the annual rings that fall into the colorimeter measuring window. Overall, the results presented in this paper can be used in the development of new methods of express wood diagnostics in construction. For citation: Fedyukov V.I., Chernov V.Yu., Chernova M.S., Tsoy O.V. Resonance Acoustic and Colorimetric Characteristics of Wood in Old Structures. Lesnoy Zhurnal = Russian Forestry Journal, 2022, no. 6, pp. 164–177. (In Russ.). https://doi.org/10.37482/0536-1036-2022-6-164-177
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Al-Fugha, Hassan, and Ahmad Al-Malabeh. "MINERALOGY, GEOCHEMISTRY AND ORIGIN OF CRETACEOUS CHERT FROM WADI AL-WALA, CENTRAL JORDAN." Iraqi Geological Journal 52, no. 1 (2019): 1–14. http://dx.doi.org/10.46717/igj.52.1.1ms-2019-06-23.
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This research is aimed at detailed investigation of the origin chert rocks in Wadi Al-Wala area in central Jordan. The chert in the area is of Upper Cretaceous in age and belongs to the widely distributed chert on the western margin of the Arabian Plate. Field characteristic structures of these cherts indicate that they occur in three forms: bedded, concretion and brecciated structure. Nine representative samples were selected for the present study. The mineralogical study shows that the chert is mainly consisted of microcrystalline quartz, calcite microcrystalline quartz, fossils and phosphatic microcrystalline quartz. The bedded chert are composed almost entirely of microcrystalline quartz and secreting organism. Geochemical investigation of Wadi Al-Wala chert shows that the content of trace elements is considerably variable, and most trace elements are low. This may indicate that the chert in the study area is resulted from the leaching of country rocks by hydrothermal solution and the evidence from submarine hydrothermal origin of silica forming this chert. This is further supported by the low MnO/Fe2O3t ratio, Cr/Zn and Ni/Zn ratios.
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Taher, Ratna, Makruf Nurudin, and Eko Hanudin. "Characteristics of Soils Developing from Gabbro, Phyllite and Chert Parent Rock in Karangsambung District." Ilmu Pertanian (Agricultural Science) 4, no. 3 (2019): 131. http://dx.doi.org/10.22146/ipas.32392.
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Understanding the nature of the soil is very important to know the potential and the proper management of the soil. This study aimed to determine the differences in morphological, physical, and chemical properties of the soils developing from gabbro, phylitte and chert parent materials. The soil profile was made to represent each parent rock of gabbro, phyllite and chert located on the upper and middle slopes with pine-dominated vegetation and mixed gardens. Observation in the field is a professional description to observe soil morphology. Soil samples were taken at each horizon to analyze soil physical properties (bulk density, particle density, and texture), soil chemical properties (pH, exchanged cations, cation exchange capacity, available P, organic C, and total N). Texture analysis results showed that clay content of the soil developing from parent rock of Gabro 1 is the highest, followed by the soil clay content from Chert 1, Phyllite 1, Chert 2, Phyllite 2, and Gabbro 2, respectively. The order of soil acidity level (pH) is Gabbro 2 > Gabbro 1> Chert 1 ~ Chert 2 > Phyllite 1 ~ Phyllite 2. Meanwhile, the order of the cation exchange capacity is Gabbro 1> Gabbro 2> Phyllite 1> Chert 1> Phyllite 2> Chert 2, and the order of the base saturation is Chert 2> Gabbro 2> Chert 1> Phyllite 2 > Phyllite1> Gabbro 1.
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Groucutt, Huw S. "Maltese chert: An archaeological perspective on raw material and lithic technology in the central Mediterranean." Malta Archaeological Review, no. 13 (December 5, 2022): 1–20. http://dx.doi.org/10.46651/mar.2022.1.
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The Maltese Islands in the central Mediterranean are renowned for their prehistoric archaeological record, particularly the megalithic ‘temples’ and associated ceramics and artwork. The temples were built by a society lacking metal technology, who relied on stone and organic materials. Knapped stone tool (lithic) technology, to produce sharp edged tools for tasks like cutting, hide working, and wood shaping offers insights into human behaviour in Malta, as well as into themes of exchange and connectivity. As well as imported chert and obsidian, local chert was widely used to make stone tools in prehistoric Malta. The local chert has generally been described as low-quality, yet relatively little research has been conducted on its distribution, characteristics, and use. In this paper I report a survey of chert sources, identifying a wider distribution of chert outcrops along the west coast of Malta than previously discussed. Some general macroscopic properties are outlined, as well as aspects of variability in the chert sources. Knapping experiments were then conducted on samples of chert collected, allowing clarification of its characteristics. These observations are used to offer some insights into lithic technology in Neolithic and Temple Period Malta, such as the hypothesis that the high frequencies of multidirectional flake production and subsequent ‘scraper retouch’ reflect adaptations to the characteristics of local chert.
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Lauziere, Andrew, Ryan Christensen, Hari Shroff, and Radu Balan. "An Exact Hypergraph Matching algorithm for posture identification in embryonic C. elegans." PLOS ONE 17, no. 11 (2022): e0277343. http://dx.doi.org/10.1371/journal.pone.0277343.
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The nematode Caenorhabditis elegans (C. elegans) is a model organism used frequently in developmental biology and neurobiology [White, (1986), Sulston, (1983), Chisholm, (2016) and Rapti, (2020)]. The C. elegans embryo can be used for cell tracking studies to understand how cell movement drives the development of specific embryonic tissues. Analyses in late-stage development are complicated by bouts of rapid twitching motions which invalidate traditional cell tracking approaches. However, the embryo possesses a small set of cells which may be identified, thereby defining the coiled embryo’s posture [Christensen, 2015]. The posture serves as a frame of reference, facilitating cell tracking even in the presence of twitching. Posture identification is nevertheless challenging due to the complete repositioning of the embryo between sampled images. Current approaches to posture identification rely on time-consuming manual efforts by trained users which limits the efficiency of subsequent cell tracking. Here, we cast posture identification as a point-set matching task in which coordinates of seam cell nuclei are identified to jointly recover the posture. Most point-set matching methods comprise coherent point transformations that use low order objective functions [Zhou, (2016) and Zhang, (2019)]. Hypergraphs, an extension of traditional graphs, allow more intricate modeling of relationships between objects, yet existing hypergraphical point-set matching methods are limited to heuristic algorithms which do not easily scale to handle higher degree hypergraphs [Duchenne, (2010), Chertok, (2010) and Lee, (2011)]. Our algorithm, Exact Hypergraph Matching (EHGM), adapts the classical branch-and-bound paradigm to dynamically identify a globally optimal correspondence between point-sets under an arbitrarily intricate hypergraphical model. EHGM with hypergraphical models inspired by C. elegans embryo shape identified posture more accurately (56%) than established point-set matching methods (27%), correctly identifying twice as many sampled postures as a leading graphical approach. Posterior region seeding empowered EHGM to correctly identify 78% of postures while reducing runtime, demonstrating the efficacy of the method on a cutting-edge problem in developmental biology.
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Bragin, Nikita, Taniel Danelian, and Frank Chanier. "Late Norian (Late Triassic) Radiolarian assemblages from chert pebbles of the Pentalofos Formation (Mesohellenic basin, Greece). Palaeogeographic implications." Bulletin de la Société Géologique de France 185, no. 2 (2014): 115–22. http://dx.doi.org/10.2113/gssgfbull.185.2.115.
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Abstract Well-preserved Late Norian Radiolaria were extracted from two pebbles of radiolarian chert included in Lower Miocene conglomerates of the Pentalofos Formation, in the area of Meteora (Mesohellenic basin, Greece). Both samples yielded a similar assemblage characterized by the presence of species Betraccium deweveri PESSAGNO & BLOME, Bipedis acrostylus BRAGIN, Pylostephanidium ankaraense BRAGIN & TEKIN and several other taxa typical of the Betraccium deweveri zone (uppermost Norian). This is the first evidence of Upper Norian radiolarian cherts from Greece. It is likely that the studied chert pebbles were derived from ophiolitic complexes or distal continental margin series situated to the east of the Mesohellenic basin; they were part of the Upper Norian oceanic realm that was obducted, during the Late Jurassic, over the Pelagonian continental crust. During the Late Miocene they were still present east of Meteora and they have been eroded since.
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Khalil, Hany, Peter O. Baumgartner, Tetsuji Onoue, et al. "Middle-Late Triassic radiolarian assemblages from chert clasts of the Excelsior Gulch conglomerate (Wallowa terrane, Oregon, U.S.A.)." Revue de Paléobiologie 39, no. 2 (2020): 565–79. https://doi.org/10.5281/zenodo.4465568.
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New radiolarian data from the polymict Excelsior Gulch conglomerate (Wallowa terrane, Blue Mountains Province, Oregon, USA) allow narrowing the age of the chert components. Chert clasts sampled at three distinct localities yielded radiolarians that have Middle to Late Triassic ranges. Individual taxon ranges allow for the distinction of four continuous substages: early Ladinian (presence of Triassocampe nishimurae and T. postdeweveri), middle Ladinian (with Pseudotriassocampe hungarica), late Ladinian (presence of Muelleritortis cochleata and Tritortis kretaensis), and early Carnian (with the co-occurrence of species such as Muelleritortis spp. ex. gr. M. cochleata, Tritortis dispiralis, ?Corum delgado and Triassocingula perornatum). The reworked chert clasts represent Middle to Late Triassic Panthalassan open ocean sediments that have not been described in the Blue Mountains Province.
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Burgess, Ray, Sarah L. Goldsmith, Hirochika Sumino, et al. "Archean to Paleoproterozoic seawater halogen ratios recorded by fluid inclusions in chert and hydrothermal quartz." American Mineralogist 105, no. 9 (2020): 1317–25. http://dx.doi.org/10.2138/am-2020-7238.
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Abstract Past changes in the halogen composition of seawater are anticipated based on the differing behavior of chlorine and bromine that are strongly partitioned into seawater, relative to iodine, which is extremely depleted in modern seawater and enriched in marine sediments due to biological uptake. Here we assess the use of chert, a chemical sediment that precipitated throughout the Precambrian, as a proxy for halide ratios in ancient seawater. We determine a set of criteria that can be used to assess the primary nature of halogens and show that ancient seawater Br/Cl and I/Cl ratios can be resolved in chert samples from the 2.5 Ga Dales Gorge Member of the Brockman Banded Iron Formation, Hamersley Group, Western Australia. The values determined of Br/Cl ~2 × 10-3 M and I/Cl ~30 × 10-6 M are comparable to fluid inclusions in hydrothermal quartz from the 3.5 Ga North Pole area, Pilbara Craton, Western Australia, that were the subject of previous reconstructions of ancient ocean salinity and atmospheric isotopic composition. While the similar Br/Cl and I/Cl values indicate no substantial change in the ocean halide system over the interval 2.5–3.5Ga, compared to modern seawater, the ancient ocean was enriched in Br and I relative to Cl. The I/Cl value is intermediate between bulk Earth (assumed chondritic) and the modern seawater ratio, which can be explained by a smaller organic reservoir because this is the major control on marine iodine at the present day. Br/Cl ratios are about 30% higher than both modern seawater and contemporary seafloor hydrothermal systems, perhaps indicating a stronger mantle buffering of seawater halogens during the Archean.
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Tzibulsky, Mark, and Vladimir Frid. "Effect of Gravel Size, Microwave Irradiation (1 to 2.5 min), Moisture, and Quenching on Aggregate Properties of Chert Gravel: Valorizing a “Waste” Byproduct of Sand Quarrying." Clean Technologies 7, no. 2 (2025): 29. https://doi.org/10.3390/cleantechnol7020029.
Full textAbstract:
Chert gravel, a byproduct of sand quarrying, remains an underutilized material in construction due to its low microwave (MW) absorption and high mechanical strength. The present study deals with the potential of MW irradiation as a novel, energy-efficient method for processing chert gravel into high-quality aggregates, reducing reliance on virgin materials. The research systematically examines MW exposure duration (1–2.5 min), rock size (150–800 g), moisture conditions, and cooling methods (air vs. water quenching) to optimize fragmentation. Experimental results indicate that larger rock sizes (600–800 g) yield coarser, less uniform aggregates, while prolonged MW exposure (>2 min) induces extensive micro-fracturing, producing finer, well-graded particles. Water quenching significantly intensifies fragmentation, generating irregular but highly fragmented aggregates, whereas pre-wetted samples exhibit finer and more uniform breakage than dry samples. The findings introduce a novel approach for optimizing chert gravel fragmentation, a material previously considered unsuitable for MW treatment. The study proposed a customizable methodology for tailoring aggregate properties through precise control of MW parameters, offering a sustainable alternative to conventional crushing. The results contribute to resource conservation, reduced energy consumption, and climate change mitigation, paving the way for more sustainable construction practices.
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HOU, Qian, Chuanlong MOU, Zuozhen HAN, Xiangying GE, and Qiyu WANG. "Origin of chert in the Upper Ordovician–Lower Silurian: implications for the sedimentary environment of North Qilian Orogen." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 112, no. 1 (2021): 13–28. http://dx.doi.org/10.1017/s1755691021000025.
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ABSTRACTDuring the Upper Ordovician–Lower Silurian, chert was widely distributed in the Zhongbao Formation in the eastern part of the North Qilian Orogen. The origin and the tectonic setting of these chert were largely unknown. In order to analyse the material provenance, sedimentary environment, their formation and the tectonic setting, we present petrology and geochemical research on chert samples collected from Shihuigou Section. The evidence provided by radiolarite occurrences, Aluminium (Al)–iron (Fe)–manganese diagram and the silicon(Si)/Si + Al + Fe + calcium ratios suggesting a non-hydrothermal input and the biogenic origin chert. The geochemical features and the petrographic signatures have shown that the chert was also influenced by a terrigenous origin. It is considered that the deposition of the Late Ordovician chert is mainly affected by tectonic collision and volcanic ash events. During the Late Ordovician–Early Silurian transition, huge amounts of volcanic ash were released by massive volcanic activity that fell into the ocean, triggering the proliferation of radiolarians. Finally, in the Late Ordovician–Lower Silurian the tectonic setting of the North Qilian Orogen was not a typical deep-water basin, nor a typical continental margin, but a multi-island deep-water basin, which is closed to the mainland.
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Palacios, Andrea, Juan José Ledo, Niklas Linde, et al. "Time-lapse cross-hole electrical resistivity tomography (CHERT) for monitoring seawater intrusion dynamics in a Mediterranean aquifer." Hydrology and Earth System Sciences 24, no. 4 (2020): 2121–39. http://dx.doi.org/10.5194/hess-24-2121-2020.
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Abstract. Surface electrical resistivity tomography (ERT) is a widely used tool to study seawater intrusion (SWI). It is noninvasive and offers a high spatial coverage at a low cost, but its imaging capabilities are strongly affected by decreasing resolution with depth. We conjecture that the use of CHERT (cross-hole ERT) can partly overcome these resolution limitations since the electrodes are placed at depth, which implies that the model resolution does not decrease at the depths of interest. The objective of this study is to test the CHERT for imaging the SWI and monitoring its dynamics at the Argentona site, a well-instrumented field site of a coastal alluvial aquifer located 40 km NE of Barcelona. To do so, we installed permanent electrodes around boreholes attached to the PVC pipes to perform time-lapse monitoring of the SWI on a transect perpendicular to the coastline. After 2 years of monitoring, we observe variability of SWI at different timescales: (1) natural seasonal variations and aquifer salinization that we attribute to long-term drought and (2) short-term fluctuations due to sea storms or flooding in the nearby stream during heavy rain events. The spatial imaging of bulk electrical conductivity allows us to explain non-monotonic salinity profiles in open boreholes (step-wise profiles really reflect the presence of freshwater at depth). By comparing CHERT results with traditional in situ measurements such as electrical conductivity of water samples and bulk electrical conductivity from induction logs, we conclude that CHERT is a reliable and cost-effective imaging tool for monitoring SWI dynamics.
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Lu, Bin, Zhen Qiu, Baohua Zhang, and Jian Li. "Geochemical characteristics and geological significance of the bedded chert during the Ordovician and Silurian transition in the Shizhu area, Chongqing, South China." Canadian Journal of Earth Sciences 56, no. 4 (2019): 419–30. http://dx.doi.org/10.1139/cjes-2018-0160.
Full textAbstract:
A large amount of bedded chert widely deposited during the Ordovician and Silurian transition in South China. In this study, analyses of the petrographic characteristics, the major elements and rare earth elements (REEs), were conducted on 31 bedded chert samples obtained from the Wufeng and Longmaxi Formations at the Qiliao section in the Shizhu area of the Sichuan Basin to determine the sedimentary environment and the origin of the bedded chert during the Ordovician and Silurian transition. The following conclusions were obtained: (i) the bedded chert in the Wufeng and Longmaxi Formations at the Qiliao Section originated mainly from terrigenous input and siliceous organisms and was slightly influenced by hydrothermal fluid, (ii) siliceous organisms were a key factor controlling the differences in the SiO2 content of the bedded chert in the Wufeng and Longmaxi Formations at the Qiliao Section, and (iii) the bedded chert in the Wufeng and Longmaxi Formations deposited in a continental margin environment during the Ordovician and Silurian transition.
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Marcos, Celia, María de Uribe-Zorita, Pedro Álvarez-Lloret, Alaa Adawy, Patricia Fernández, and Pablo Arias. "Quartz Crystallite Size and Moganite Content as Indicators of the Mineralogical Maturity of the Carboniferous Chert: The Case of Cherts from Eastern Asturias (Spain)." Minerals 11, no. 6 (2021): 611. http://dx.doi.org/10.3390/min11060611.
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Chert samples from different coastal and inland outcrops in the Eastern Asturias (Spain) were mineralogically investigated for the first time for archaeological purposes. X-ray diffraction, X-ray fluorescence, transmission electron microscopy, infrared and Raman spectroscopy and total organic carbon techniques were used. The low content of moganite, since its detection by X-ray diffraction is practically imperceptible, and the crystallite size (over 1000 Å) of the quartz in these cherts would be indicative of its maturity and could potentially be used for dating chert-tools recovered from archaeological sites. Also, this information can constitute essential data to differentiate the cherts and compare them with those used in archaeological tools. However, neither composition nor crystallite size would allow distinguishing between coastal and inland chert outcrops belonging to the same geological formations.
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Suriamin, Fnu, and Matthew J. Pranter. "Stratigraphic and lithofacies control on pore characteristics of Mississippian limestone and chert reservoirs of north-central Oklahoma." Interpretation 6, no. 4 (2018): T1001—T1022. http://dx.doi.org/10.1190/int-2017-0204.1.
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We have determined how stratigraphy and lithofacies control pore structures in the Mississippian limestone and chert reservoir of north-central Oklahoma. There are 17 lithofacies and 29 high-frequency cycles documented in the Mississippian interval of this study. The high-frequency cycles have thicknesses ranging from 0.3 to 30.5 m (1–100 ft) and are mainly asymmetric regressive phases. The pore characteristics, measured through digital-image analysis (DIA) of thin-sections photomicrographs ([Formula: see text]100), exhibit unique correlations with core porosity, permeability, and lithofacies within a sequence-stratigraphic framework. There are five fundamental correlations observed. First, porosity from DIA and laboratory core measurements has a strong positive relationship ([Formula: see text]). However, some values from DIA porosity yield relatively higher values, specifically in spiculitic mudstone wackestones and argillaceous spiculitic mudstone wackestones. The difference is hypothesized due to the presence of isolated nanopores that are not accessible by helium during measurement of core porosity. Second, the relationship between pore circularity and permeability is indeterminate. The indeterminate relationship is related to a complex internal pore network, intensive diagenetic alteration, an unconnected microfracture network, and isolated pores. Third, positive moderate to strong correlations ([Formula: see text]) between porosity and permeability are observed only in four lithofacies. Fourth, coarse-grained lithofacies within the uppermost depositional sequence of the Mississippian interval have a heterogeneous pore-size distribution, whereas fine-grained lithofacies tend to exhibit a homogeneous pore-size distribution. Fifth, higher reservoir quality is associated with the upper intervals of high-frequency shallowing-upward cycles. This confirms that the sequence-stratigraphic variability of lithofacies is important to predict reservoir quality and its distribution. An alternative graphical method of pore-size distribution is also developed. To be a useful “technique,” examples of the plot are demonstrated using samples in this study. The plot successfully provides simple identification of pore-size classes, quantitative percentage of pore-size class, dominant pore class, and approximate minimum and maximum pore size.
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Barannikova, S. A. "Localized deformation at initial stages of plastic flow in high-manganese steel." Izvestiya. Ferrous Metallurgy 65, no. 10 (2022): 699–705. http://dx.doi.org/10.17073/0368-0797-2022-10-699-705.
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The work is devoted to the study of macroscopic localization of plastic deformation during uniaxial tension of single crystals of the Hadfield steel (Fe – 13 % Mn – 1.03 % C). In the course of studies at the stage of easy sliding, significant differences were found in the nature of macrolocalization of plastic deformation in the single-crystal samples under study. All patterns of deformation localization observed in these cases can be divided into two types. The first type of strain localization corresponds to the initiation at the upper yield point and further propagation of the strain front, which gradually transfers the sample material from undeformed state to deformed one. This manifested itself most clearly in single crystals oriented along the tension axis [377] and [355], where the strain localization pattern appears as a single zone of localized deformation on the yield plateau. Such a deformation front passes through the sample volume only once as a Chernov-Luders band. In this case, the flow of the material is carried out without hardening until all its elements are transferred to the deformed state. Single zones of strain localization were also observed at the stages of easy sliding and yield plateau in the Hadfield steel single crystals oriented along the tension axis [123] and [012]. In the second type of localization, at the stage of easy sliding, synchronous movement along the pattern of several deformation centers occurs. Their movement can be unidirectional and counter, and the speeds are both the same and different from each other. Further deformation of the Hadfield steel single crystals oriented along the tension axis [355] or [012], led to the movement of two deformation localization centers at the stages of easy sliding. In single crystals oriented along [111], the strain localization pattern is respectively represented as four localized strain sites. Consequently, the synchronous movement of deformation fronts occurs along an already deformed, albeit to a small extent, material. As a reason for the difference between the two types of macrostrain localization at stage I (the easy sliding stage and the yield plateau), the number of active sliding systems or tensile twinning in the studied single crystals can be discussed based on crystallographic analysis and metallographic studies.
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Zhurilo, A. A., A. I. Barbova, Yu A. Cherednik, et al. "COMPARISON OF GENEXPERT MTB/RIF AND GENOTYPE SYSTEMS WITH MTBDRPLUS STRIPS FOR DETECTION OF MUTATIONS THAT ARE ASSOCIATED WITH M. TUBERCULOSIS RESISTANCE TO RIFAMPICIN IN TUBERCULOSIS." Ukrainian Pulmonology Journal 30, no. 4 (2022): 34–41. http://dx.doi.org/10.31215/2306-4927-2022-30-4-34-41.
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COMPARISON OF GENEXPERT MTB/RIF AND GENOTYPE SYSTEMS WITH MTBDRPLUS STRIPS FOR DETECTION OF MUTATIONS, ASSOCIATED WITH M. TUBERCULOSIS RESISTANCE TO RIFAMPICIN IN TUBERCULOSIS A. A. Zhurilo, A. I. Barbova, Yu. A. Cherednik, P. S. Trofi mova, S. V. Mironchenko, O. V. Pavlova, A. V. Chernov, L. M. Sladkova Summary The aim was to analyze the level of compliance of two molecular genetic methods GeneXpert MTB/RIF and GenoTypeDRplus in determining the drug resistance of M. tuberculosis to rifampicin when detecting mutations in the RRDR region associated with drug resistance. Object and methods. We studied strains of M. tuberculosis with resistance to rifampicin, which was detected by any of the studied molecular genetic methods. 96 sputum samples were taken. Sputum smears were examined for the presence of acid-fast bacteria by microscopy after staining with the Ziehl-Neelsen method. The material was inoculated into Middlebrook 7H9 broth and on Lowenstein-Jensen medium. The liquid medium was incubated in the BACTEC MGIT system. An immunochromatographic test was used to identify the strains. The drug susceptibility test of M. tuberculosis to rifampicin was performed using the BACTEC MGIT system. The GeneXpert MTB/RIF test was performed according to the manufacturer’s instructions. The GenoTypeDRplus assay was performed on decontaminated and concentrated sputum samples. The process was carried out in three stages: DNA extraction from the processed sputum sample; amplification of the RRDR region by PCR; hybridization of the PCR product to specific oligonucleotide probes immobilized on the test strip. For sequencing, M. tuberculosis DNA isolation was performed using the QIAamp® DNA Mini Kit. The DNA concentration was measured on a Denovix Quantus spectrophotometer. Targeted panel amplification was performed using the Deeplex Myc-TB kit. Amplicon purification was performed using Agencourt AMPure XP magnetic beads. Quantitative analysis of the purified amplification products was performed using a Qubit fluorometer. The M. tuberculosis DNA library was prepared for sample sequencing using the Nextera XT DNA library preparation kit. The library used 5.0 μl of input DNA at a concentration of 0.2 ng/μl. Sequencing was performed on MiSeq equipment with the library normalization and denaturation protocol. Results and discussion. The GeneXpert MTB/RIF and MTBDRplus systems target the same 81 bp rifampicin resistance domain. (RRDR) subunits of bacterial RNA polymerase (rpoB) for mutation detection using DNA probes, i.e. there is a correspondence of probes to each other and an expected similarity of probe binding. We analyzed all sputum samples using GeneXpert MTB/RIF and GenoType MTBDRplus and phenotypic BACCTEC MGIT methods. The level of agreement between two molecular genetic methods for the detection of rifampicin-associated mutations in the RRDR region has been established. The RRDR 81bp region of the rpoB gene of mismatched cases was studied by sequencing. GeneXpert MTB/RIF and GenoType DRplus matched the phenotypic method in 92.7% and 89.6% of cases of M. tuberculosis resistance, respectively. Complete agreement between the results of GeneXpert MTB/RIF and GenoTypeMTBDRplus was observed in 92.7% of cases. GeneXpert MTB/RIF and GenoType DRplus showed a similar pattern of binding failure of wild type probes (WT-probes) when scanning the 81 bp region (RRDRdomain), which leads to stability diagnostics through probe failure software. Sequencing of the RRDR region of “mismatched” strains showed that GeneXpert probes detected seven “mismatched” cases correctly, and GenoTypeDRplus was erroneous in all cases. GeneXpert has demonstrated greater accuracy in R-resistance detection for mismatched isolates compared to GenoTypeDRplus. GeneXpert MTB/RIF has a number of other benefits over GenoTypeDRplus. GeneXpert MTB/RIF is relatively easier to implement, biosafety requirements are minimal, study times are shorter, and the study process is more automated, resulting in less human error and more reproducible results. Given these facts and the results of GeneXpert MTB/RIF found in the study, it is recommended that GeneXpert MTB/RIF be used to detect MDR-TB. Conclusions. Sequencing of the 81bp RRDR region of mismatched M. tuberculosis strains showed that GeneXpert MTB/RIF performed more accurately than GenoTypeDRplus in detecting mutations associated with rifampicin resistance. GeneXpert MTB/RIF is relatively easier to perform, biosafety requirements are minimal, time to study is shorter, and the study process is more automated, resulting in less human error and greater reproducibility of results, so it is reasonable to use it for the detection of multidrug-resistant tuberculosis. The Deeplex Myc-TB analytical solution delivers a wealth of insightful information from antimycobacterial drug resistance markers and speeds up data analysis with easy-to-use software. Key words: tuberculosis, Mycobacterium tuberculosis, drug resistance, GeneXpert MTB/RIF and GenoTypeDRplus molecular genetic systems, BACTEC MGIT phenotypic system, sequencing. Ukr. Pulmonol. J
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Refet-Mollof, Elena, Ouafa Najyb, Rodin Chermat, et al. "Abstract B005: Hypoxic sarcoma spheroid on a chip: Insights into treatment response." Clinical Cancer Research 28, no. 18_Supplement (2022): B005. http://dx.doi.org/10.1158/1557-3265.sarcomas22-b005.
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Abstract Context: Hypoxia is found in at least 47% of soft-tissue sarcoma (STS) patients and is known to be a major contributor to treatment resistance, metastasis progression and associated with poor prognosis. Indeed, expression of hypoxic proteins (HIF1-α, CAIX) in STS is associated with a shorter overall survival, and a shorter progression-free survival in patients. Specifically, Yang et al. demonstrated in 2017 that patients stratified by a 24-gene hypoxia signature had a poorer distant metastasis free survival. Nevertheless, hypoxia is seldom considered during treatment development due to the lack of a user-friendly way to culture naturally hypoxic 3D tumor models. Therefore, we developed a user-friendly in vitro preclinical tool allowing the study of natural chronic hypoxia and its effect on treatment response. Methods: Microfabrication technologies were used to design a microfluidic chip allowing culture, maintenance, treatment, and analysis of 240 STS naturally hypoxic spheroids (750µm of diameter). SK-LMS-1 Human leiomyosarcoma and STS117 (human primary undifferentiated pleomorphic sarcoma cells) spheroids were formed 48h after seeding. Gold-standard hypoxic protein Hypoxia Inducible Factor 1 alpha (HIF1- α) and Carbonic Anhydrase IX (CAIX) expression was assessed by Western Blot (WB). Spatial distribution of CAIX was assessed by immunofluorescence (IF). Based on the IF, an in silico model of the oxygen consumption of the spheroids was built using COMSOL. As a proof of concept, the spheroids were treated using two oxygen-dependent treatment: RT and hypoxia prodrug Tirapazamine (TPZ). DNA-damages were quantified using yH2AX in IF to assess treatment efficacy. Results: These spheroids on-a-chip are the largest to date (&gt;750µm), and express gold-standard hypoxic protein CAIX in their core only, a feature absent in spheroids of 450µm of diameter of the same cell lines. HIF1-α expression patterns were cell line dependent. CAIX expression in SK-LMS-1 and STS117 large spheroids was respectively 7.8 and 24 times higher than in 450µm spheroids. Quantification of DNA damages (count of yH2AX foci/nuclei area in mm²) demonstrated that TPZ preferentially targets the hypoxic core. However, the response (DNA damages) to RT alone showed no evidence of radioresistance of the hypoxic regions, on samples fixed 24h after irradiation. A possible explanation could be that, in 24h, the oxygen-dependent DNA repair and the accumulation of DNA damages in hypoxic regions hide the oxygen-dependent radioresistance. Therefore, quantification of DNA damages with yH2AX 30min after irradiation is currently being investigated, as maximum DNA damage response has been shown to be observed at this time point. Our 750µm spheroids naturally display a hypoxic core expressing gold-standard hypoxic protein CAIX at 120µm of depth, a feature absent in smaller spheroids. Together, these results cement our microfluidic device and our spheroids as a potent fundamental and pre-clinical tool to explore the biology of hypoxia on 3D tumor model, its effects on treatment response. Citation Format: Elena Refet-Mollof, Ouafa Najyb, Rodin Chermat, Audrey Glory, Julie Lafontaine, Philip Wong, Thomas Gervais. Hypoxic sarcoma spheroid on a chip: Insights into treatment response [abstract]. In: Proceedings of the AACR Special Conference: Sarcomas; 2022 May 9-12; Montreal, QC, Canada. Philadelphia (PA): AACR; Clin Cancer Res 2022;28(18_Suppl):Abstract nr B005.
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Benfrika, El Mostafa, and Mohamed Raji. "Conodont biostratigraphy of Upper Silurian formations from the Rabat-Tiflet area (northwestern Meseta, Morocco)." Bulletin de la Société Géologique de France 174, no. 4 (2003): 337–42. http://dx.doi.org/10.2113/174.4.337.
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Abstract Silurian sections from the Rabat-Tiflet area (northwestern Moroccan Meseta) have been systematically sampled for conodonts. The conodont faunas are characterized by two index species of the European Silurian zonation (Ozarkodina sagitta sagitta and Ozarkodina remsceidensis eosteinhornensis) and two other index species of the north American zonation (Kockelella stauros and Kockelella variabilis). Recognition of the sagitta/stauros through lower variabilis zones in the lower part of the Silurian limestone and shale succession from the Rabat-Tiflet area, proves for the first time the presence of Wenlock below Ludlow-Pridoli, in the Silurian sequences of this area. Most of the Silurian from the northwestern Moroccan Meseta is represented by black graptolitic shales with intercalations of limestone (beds or lenses) in its upper part. The Silurian biostratigraphy of Morocco is generally based on graptolites [Willefert in Destombes et al., 1985]. In the present contribution the age of some Silurian sections (fig. 3) from the Rabat-Tiflet area is re-assessed by using conodonts. The stratigraphically important taxa have been described in Benfrika [1999]. Section Oued Grou I (G I) Situated near the barrage Mohamed Ben Abdellah, this section shows 30 m of alternating black shales and limestones. The lower part of this unit (I) provided : Ozarkodina sagitta sagitta, Kockelella absidata, Kockelella stauros, Ozarkodina bohemica, Ozarkodina excavata, Dapsilodus obliquicostatus, Panderodus unicostatus, Pseudooneotodus bicornis. The first appearance of Oz. sagitta sagitta and the K. stauros indicates the lower boundary of sagitta Zone established by Walliser [1964] in the Carnic Alps and also the lower boundary of stauros Zone proposed by Barrick et Klapper [1976] for North America (fig. 2). These species are of Wenlock age. Section Oued Grou II (G II): This section is located at approximately a hundred meters north of the preceding section. It is subdivided into 2 units : Unit IIA : 12 m of greyish to black limestones interbedded with green shales ; Unit IIB : 65 m of shales interbedded with some limestones. The conodonts identified in unit A are : Ozarkodina bohemica, Kockelella absidata and Kockelella stauros. This fauna is of Wenlock age. The first occurrence of Kockelella variabilis in sample indicates the lower variablis zone (lower part of Ludlow). Section Al Khaloua Iron Mines (AK) The limestones interbedded with shales of the lower part of the Al Khaloua section yield Polygnathoides emarginatus and Kockelella variabilis. This association is of Ludlow age. The conodonts from the upper part of this section (Caudicriodus sp. and Belodella devonica) indicate a Lower Devonian age. Section Oued Tiflet syncline (T) Two units are recognized : Unit A : 18 m of alternating black shales and greyish black limestones providing : Kockelella absidata, Ozarkodina bohemica, Decoriconus fragilis, Dapsilodus obliquicostatus, Ozarkodina excavata. This fauna is of Upper Wenlock to Lower Ludlow age ; Unit B : 34 m of black shales with some limestone intercalations, is probably of Ludlow-Pridoli age. Conclusion The Silurian conodont succession recognized in the Rabat-Tiflet area (northwestern Moroccan Meseta) allows to attribute the lower part of alternating limestones and shales to the Wenlock and the upper part to the Ludlow-Pridoli. The presence of the Wenlock in the Rabat-Tiflet area and also in the Oued Cherrat (under investigation) is demonstrated by conodonts. This suggests that the Silurian transgression has reached this area of the Moroccan Meseta during the Wenlock and not the Ludlow, as generally admitted. Furthermore, the conodont faunas allow to recognize affinities with those from North America and Central Europe. Two index species of the conodont zonation established by Walliser [1964] for the Carnic Alps have been recognized in Morocco, two other index species of the conodont zonation proposed by Barrick and Klapper [1976] for North America have been also identified in Morocco.
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Bujanov, P. M. "Ecological problems of sandy area afforestation in the south of Ukraine." Ecology and Noospherology 25, no. 1-2 (2014): 92–100. http://dx.doi.org/10.15421/031409.
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The town of Oleshky, renamed as Tsiurupinsk in 1928, is located in the Kherson region of Ukraine, near the railway station Tsiurupinsk. The Nizhnyodniprovsky Research Station "Afforestation of sands and viticulture" is located here. The total area of forest fund in Kherson region is 221.7 thousand hectares. The percentage of forest land is 3.3 %. 45 thousand hectares of this area belong to Tiurupinsk forest. The tree composition involves 74 % of coniferous and 26 % of deciduous breeds. 62 % of Cherson forests were created by man. The pine forests on the Oleshkovsky (Nizhnyodniprovsky) sands were created in the middle of the XIX сentury. This was dictated by the urgent task of fixing the sands by the black storms, using the fertility of sands in forest managment and agriculture. Completely joining the authors of papers devoted Oleshkovsky sands, their afforestation, recreation, conservation and management of the southern pine forest complexes, we consider important to mention: in harsh growing conditions of pine trees it is extremely necessary to strive for a complex biogeocenological research, to a comprehensive in-depth knowledge of pine ecosystems, at which typological approach is obligatory not from the standpoint of common assessments of forest growth conditions, but using typological principles of Professor A. L. Belgard established for the conditions of geographical and often environmental inadequacy of forest to habitat conditions; the typology provides diversity of soil types of Oleshkovsky forest growth conditions where there are two variants of soils – with and without salinity, with different gradations of humidification – from very dry to wet soils; it is necessary to take into account the extent of the influence of planted forests on the environment, which depends primarily on the ecological forest structure, which refers to the light structure of the stands and the duration of their habitat transforming influence. Light structure, in its turn depends on the architectonics of the tree crowns forming part of the forest (Belgard, 1971); using the special equipment it is necessary to create or improve the network of hydrological monitoring wells covering all environmental profiles, catens and plots, to conduct large-scale monitoring studies of the cyclic and successional forms of dynamics of forest hydrology: groundwater level, the chemistry, radioecology, organic matter, biota and also flow direction of groundwater movement (hydraulically interconnected), their degree of contamination, sanitary toxicological and other features; to explore sandy soils for content and quality of humus to evaluate soil fertility (Orlov, 1981); to explore microclimatic regimes to identify critical data to the vitality of pine plantations; with all indicators of systematic characteristics of a pine (Pinus silvestris L.), it has about 100 species. In the culture of Ukraine there are about 35 species. But, as foresters observe, not every pine (Pinus silvestris L.). gives a good effect of growth and development in every kind of environmental ecotope. It is necessary to consider the differences between hereditary traits of burned 350 years old samples of the eternal pinewood in Samarsky forest and artificial pine plantations grown from seed material taken from a completely different habitat conditions. Oak acorns, collected in the floodplain of River Dniester and planted in the watershed of Gyrnetsovy forest in Moldavia, dieback at the age of 30 years, but oak acorns, collected in plakor conditions and landed next to the first, have high vitality, intensive growth and development. It is well known that the Scots pine (Pinus silvestris) and Cretaceous pine (Pinus cretacea) do not differ in systematics. But Scots pine planted on chalk mountains near Scots pine are different. The first pine does not give seed regeneration, and the second one has acquired the ability to reproduce itself easily on Cretaceous and to hоld on barren rock outcrops (Milkov, 1959); in the study of sandy habitats it is necessary to establish consort links in biogeocenoses, their horizontal and vertical structures, ecomorphic features of the forest, its age population type, and as a result - to establish the viability and sustainability of pine plantations to the conditions; finally, it should be emphasized that only a comprehensive and integrated approach to the study of forest ecosystems in the steppe (horizontal and vertical structure) can give a reliable information about the successfully constructed plantation, its stability and durability.
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Wang, Chenyu, Hanting Zhong, Han Yan, Lingxue Gao, Hu Huang, and Mingcai Hou. "Global Chert Database: A summary record of global chert samples." Geoscience Data Journal, March 14, 2024. http://dx.doi.org/10.1002/gdj3.244.
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AbstractChert is a sedimentary rock abundant and conspicuous throughout the geologic record. It serves as an essential geological archive and is vital for palaeogeographic reconstruction. The Chert Database Working Group is part of the OneSediment Working Groups of the Deep‐time Digital Earth (DDE) Big Science Program. To facilitate the sharing of chert information and promote chert research, we have compiled a summary of literature containing chert information worldwide and established the Global Chert Database (GCDB). The main body of the current database consists of seven data tables, each providing details on references, lithology, depositional age, geographic location, depositional environment and geochemical information for each sample. As of December 2023, the GCDB contains 8417 sample data from 617 pieces of literature, which can be downloaded from the ‘DDE Data Publish & Repository’.
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Kondratev, S. I., and D. S. Khoruzhii Khoruzhii. "Vertical Distribution of Phosphates in the Black Sea Based on the Expeditionary Data, 2016–2019." Morskoy gidrofizicheskiy zhurnal 37, no. 5 (2021). http://dx.doi.org/10.22449/0233-7584-2021-5-579-590.
Full textAbstract:
Purpose. The purpose of the study is to analyze the features of vertical distribution of phosphates and dissolved organic phosphorus (Porg) in the Black Sea at the present period. Methods and Results. The data obtained by the scientists of Marine Hydrophysical Institute in the Black Sea within the economic zone of Russia in 2016–2019 were used. At more than 200 deep-sea stations, a cassette of 12 bathometers (the Seabird-Electronics STD-instrument) was applied for taking hydrochemical samples at certain isopycnic surfaces, usually at σt = 16.30; 16.25; 16.20; 16.20; 16.15; 16.10; 16.05; 16.00; 15.95; 15.90; 15.80; 15.50, 14.0 kg/m3. At the coastal shallow-water stations, samples were taken at the 10 m intervals. Such a scheme permitted to carry out vertical sampling in the upper mixed layer and in the suboxic zone (including its upper boundary) with possible minimum of phosphates, to determine the depth of hydrogen sulfide formation and the location of the phosphates concentration maximum in the upper part of the anaerobic zone. Conclusions. From the surface to isopycn σt = 14.4 kg/m3, the content of phosphates and Porg does not exceed 0.1 µM; below this isopycnic surface, the phosphates concentration begins to increase, whereas of Porg remains at the same level. At all the profiles of the phosphates vertical distribution, the phosphates concentration minimum was recorded near the isopycnic surface σt = 15.8 kg/m3, and its maximum – near the isopycnic surface σt = 16.2 kg/m3. The minimum content of phosphates varied within 0–1.5 µM; in 2016–2017 the phosphates concentration maximum did not exceed 8 µM; in 2018, in many cases, it was higher than 12 µM, and once, near the Kerch Strait, it exceeded 17 µM. Increase in the magnitude of the maximum phosphates concentration (in the previous studies in 1988– 2013, it did not exceed 8 µM) is assumed to be related to installation of the supports for constructing the Kerch Bridge.
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Fioretti, Giovanna, Giacomo Eramo, Italo M. Muntoni, Alessandro Monno, Attilio Galiberti, and Massimo Tarantini. "SiLiBA: Building the geological chert lithotheque." Journal of Lithic Studies 10, no. 2 (2023). http://dx.doi.org/10.2218/jls.7251.
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Lithotheques collect and exhibit raw material used by human communities for the manufacturing of objects during the Prehistory and represents an important tool of their knowledge. These collections are essential in the procuring and provenance study of archaeological lithic industries. 
 This paper aims, firstly, to introduce SiLiBA, the lithotheque of the Earth and Geoenvironmental Sciences Department of the University of Bari Aldo Moro (Italy), as reference collection in the archaeological field studies, and secondly to propose guidelines and rules to build a lithotheque. The collection consists of about 900 pieces of geological cherts, which are the result of an expanded collecting action of primary and secondary cherts across Italy (Apulia, Basilicata, Sicily), Croatia, and Switzerland, belonging to formations from the Cretaceous to the Quaternary Period. All the chert samples were described according to the non-destructive multiparametric protocol for chert investigation (NM-PCI), providing a modular dataset of binary, ordinal and continuous variables which integrates petrographycal, micropaleontological, chemical and physical data. Such results were summarized in suitable reports, with also geographic coordinates, geological description and photographic documentation, in a digital database, which will be soon online. Cherts are grouped in 37 suitable boxes, following geographic hierarchical organisation and reporting informative labels. Some representative samples are exposed in the Earth Sciences Museum of the same University. Furthermore, the lithotheque is equipped by a dedicated laboratory which includes optical microscopes, a glossmeter and a spectrophotocolorimeter. The promotion in the last years was guaranteed by dissemination activities for educational and academic communities, including an interactive laboratory of experimental archaeology.
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Md Razak, Mohd Razali, Zaleha Kassim, Asnor Azrin Sabuti, and Ahmad Ismail. "Feeding ecology and food preferences of Cherok Paloh, Pahang horseshoe crab, Tachypleus gigas." Malaysian Journal of Fundamental and Applied Sciences 13, no. 3 (2017). http://dx.doi.org/10.11113/mjfas.v13n3.684.
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Intensive previous studies on horseshoe crabs feeding ecology were mostly focus on Limulus polyphemus. Their food preference might be different depend on the availability and abundance of feeds in the particular environment. This paper aims to investigate the feeding ecology and food preferences of Cherok Paloh, Pahang Tachypleus gigas. Ten samples of male and female horseshoe crabs, Tachypleus gigas were trapped in fishing net during the incoming high tide and 20 samples of male and female were hand-harvested at the spawning beach; 10 samples during pre-mating and 10 samples during post-mating. Their gut content was analysed by the Electivity Index. Results showed that Tachypleus gigas coming to spawn with full gut content. Echinoderm served as a main food composition in the gut of males (50%) and females (51.94%) during the open sea migration phase. The main composition was substituted by macrophyte (males: 59.51% to 65.15%; females: 36.36% to 58.10%) as they arrived to shore. Based on Electivity Index, male crabs showed positive preference toward polychaete (EI: 0.04) and macrophyte (EI: 0.19) at the spawning site while, the females showed positive preference toward bivalve (EI: 0.46). Further study on feeding ecology is needed in order to improve the population of Tachypleus gigas in Malaysia.
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Munoz, Patricio, Jan Ilavsky, Matthew Newville, et al. "(U)SAXS characterization of porous microstructure of chert: insights into organic matter preservation." Journal of Applied Crystallography 56, no. 6 (2023). http://dx.doi.org/10.1107/s1600576723008889.
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This study characterizes the microstructure and mineralogy of 132 (ODP sample), 1000 and 1880 million-year-old chert samples. By using ultra-small-angle X-ray scattering (USAXS), wide-angle X-ray scattering and other techniques, the preservation of organic matter (OM) in these samples is studied. The scarce microstructural data reported on chert contrast with many studies addressing porosity evolution in other sedimentary rocks. The aim of this work is to solve the distribution of OM and silica in chert by characterizing samples before and after combustion to pinpoint the OM distribution inside the porous silica matrix. The samples are predominantly composed of alpha quartz and show increasing crystallite sizes up to 33 ± 5 nm (1σ standard deviation or SD). In older samples, low water abundances (∼0.03%) suggest progressive dehydration. (U)SAXS data reveal a porous matrix that evolves over geological time, including, from younger to older samples, (1) a decreasing pore volume down to 1%, (2) greater pore sizes hosting OM, (3) decreasing specific surface area values from younger (9.3 ± 0.1 m2 g−1) to older samples (0.63 ± 0.07 m2 g−1, 1σ SD) and (4) a lower background intensity correlated to decreasing hydrogen abundances. The pore-volume distributions (PVDs) show that pores ranging from 4 to 100 nm accumulate the greater volume fraction of OM. Raman data show aromatic organic clusters up to 20 nm in older samples. Raman and PVD data suggest that OM is located mostly in mesopores. Observed structural changes, silica–OM interactions and the hydrophobicity of the OM could explain the OM preservation in chert.
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Sánchez, de la Torre Marta, Anikó Angyal, Zsófia Kertész, et al. "Trace element mapping of two Pyrenean chert deposits (SW Europe) by PIXE." June 1, 2017. https://doi.org/10.1016/j.nimb.2017.04.016.
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The geochemical character of two chert formations from the Pyrenean mountain range (SW Europe) was established by PIXE analyses. While it was not possible to distinguish the formations through reference to major and minor elements, some variations were revealed at the trace elemental level. In order to determine if these elements are associated with the Si matrix or to the contents of a specific inclusion, elemental maps were acquired and the elemental composition of the identified inclusions were also determined. As a result, Sr, Ni and Zn are better represented in Montgaillard samples while Y, Hf, W and Zr are typical of Montsaunès cherts. Thanks to elemental maps it has been possible to determine that most of these characteristic elements are usually related to a specific inclusion content.