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Open Journal of Geology 2019年第8期9卷 474-496页

作者： tamara bayanova Viktor Subbotin Svetlana Drogobuzhskaya Anatoliy Nikolaev Ekaterina Steshenko Geological Institute Kola Science Centre Russian Academy of Sciences Apatity Russia Tananaev Institute of Chemistry Kola Science Centre Russian Academy of Sciences Apatity Russia

Baddeleyite is an important mineral geochronometer. It is valued in the U-Pb (ID-TIMS) geochronology more than zircon because of its magmatic origin, while zircon can be metamorphic, hydrothermal or occur as xenocrysts. Detailed mineralogical (BSE, KL, etc.) research of baddeleyite started in the Fennoscandian Shield in the 1990s. The mineral was first extracted from the Paleozoic Kovdor deposit, the second-biggest baddeleyite deposit in the world after Phalaborwa (2.1 Ga), South Africa. The mineral was successfully introduced into the U-Pb systematics. This study provides new U-Pb and LA-ICP-MS data on Archean Ti-Mgt and BIF deposits, Paleoproterozoic layered PGE intrusions with Pt-Pd and Cu-Ni reefs and Paleozoic complex deposits (baddeleyite, apatite, foscorite ores, etc.) in the NE Fennoscandian Shield. Data on concentrations of REE in baddeleyite and temperature of the U-Pb systematics closure are also provided. It is shown that baddeleyite plays an important role in the geological history of the Earth, in particular, in the break-up of supercontinents.

关键词： Baddeleyite PGE U-Pb Isotope Data Geochronology Paleoproterozoic PGE Layered Intrusion Complex Deposits Paleozoic Fennoscandian Shield

The Oldest Grey Gneisses and Tonalite-Trondhjemite Granodiorites in the Fennoscandian Shield: ID-TIMS and SHRIMP Data

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Open Journal of Geology 2020年第2期10卷 124-136页

作者： tamara bayanova Evgeniy Kunakkuzin Pavel Serov Ekaterina Steshenko Elena Borisenko Alexander Larionov Olga Turkina Geological Institute KSC RAS Apatity Russian Federation A.P. Karpinsky Russian Geological Research Institute (VSEGEI) St. Petersburg Russian Federation Institute of Geology and Mineralogy Siberian Branch RAS Novosibirsk Russian Federation

Genesis of the oldest continental crust retains a marked trace in the Earth’s evolution over its 4.5 Ga history. Despite ample isotope data on the role of the continental crust in the Earth’s evolution, there has been much debate on the origin of grey gneisses and tonalite-trondhjemite-granodiorites (TTG). Precise U-Pb (ID-TIMS) and SHRIMP data on single zircon for paragneisses and TTG (3158.2 ± 8.2 Ma) have indicated the Central-Kola and Belomorian (White Sea) megablocks of the Fennoscandian Shield to be 3.16 Ga and 3.70 Ga, respectively. The newly obtained ages of zircon from these megablocks indicate the origin of the discrete continental crust to be 3.16 and 3.70 Ga. It is close to the Nordsim zircon data on the Siurua TTG (Finland), which are 3.45 and 3.73 Ga in the core. The new summarized data on the Earth’s oldest rocks (basement and continental crust) indicate the younger age of the rocks in the Fennoscandian Shield as compared to those in Australia (Kronendonk et al., 2019).

关键词： Fennoscandian Shield Geochronology Hadean ID-TIMS SHRIMP TTG Grey Gneiss

New U-Pb and Sm-Nd Data and REE Distribution in Sulphides of Paleoproterozoic PGE Layered Intrusions in the Arctic Part of the Fennoscandian Shield

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Open Journal of Geology 2019年第11期9卷 768-782页

作者： tamara bayanova Irina Elizarova Pavel Serov Nadezhda Ekimova Evgeny Kunakkuzin Ekaterina Steshenko Yury Neradovsky Markku Iljina Dmitry Zhirov Geological Institute of the Kola Science Centre Russian Academy of Sciences Apatity Russia Institute of the North Industrial Environmental Problems of the Kola Science Centre Russian Academy of Sciences Apatity Russia Geological Survey of Finland Rovaniemi Finland

The U-Pb (on zircon) and Sm-Nd analysis is a popular isotope-geochronological tool for estimating the age of rocks from PGE mafic-ultramafic intrusions. Sulphides can be used to study the geochronology of ore processes as well, since they should indicate the time of ore mineralization. Gabbronorite has been sampled from the Passivaara reef at the Penikat layered intrusion (Finland) for U-Pb and Sm-Nd isotope single zircon analyses in order to separate sulphide minerals. The Sm-Nd isotope age of gabbronorite has been dated at 2426 ± 36 Ma;eNd(T) = −1.4 ± 0.4. The Sm-Nd isotope age on sulphides and rock-forming minerals reflects the crystallization time of the ore-bearing gabbronorite from the Passivaara reef of the Penikat layered intrusion. The mass-spectrometer analytical environment and modes of operation have been adjusted to detect REE in sulphide minerals on example of pyrite from the PGE Penikat layered intrusion (Finland) and chalcopyrite from the Talnakh deposit (Norilsk area, Russia) has been estimated. The total REE content in pyrite is ca. 3.5 ppm, which is enough to define the Sm-Nd age of pyrite. The study shows how to use the mineral/chondrite spectra to evaluate the accuracy of the REE analytical results on example of State Standard Sample 2463 (Russia).

关键词： Platinum Group Elements Layered Intrusion Rare Earth Elements Uranium-Lead and Samarium-Neodymium Analyses Zircon Sulphide Minerals Fennoscandian Shield

Resource discovery in distributed digital libraries through visual knowledge navigation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第11期6卷 1306-1311页

作者： AHMAD Faisal SUMNER tamara Department of Computer Science University of Colorado Colorado 80309-0430 USADepartment of Computer Science University of Colorado Colorado 80309-0430 USA

In order to support users to search and browse for various resources, digital libraries are composed of discovery systems which provide user interface and information retrieve system. Recent researches in Information Retrieval have investi- gated different techniques through improving precision and recall to enhance the effectiveness of discovery system in digital libraries. In this paper, we present our work to enhance discovery system effectiveness with a different approach, through resource discovery based on visual knowledge navigation. In our Strand Map Services project under National Science Digital Library, we introduce the visual resource discovery system called conceptual browsing interfaces, to help educators and learners to locate, comprehend and use educational resources in digital libraries. The paper begins with a short introduction of the Strand Map Services. Then we illustrate the service architecture, the design and implementation of its major components. We will focus our discussion of how the visualization system of the Strand Map Services supports the visual knowledge navigation for distributed digital libraries. This includes the knowledge acquisition of the conceptual browsing interfaces, different knowledge representa- tions in the system perspective and user interface perspective, visualization system modules, algorithm and Web services inte- gration to use visual knowledge navigation to enhance resource discovery in digital libraries.

关键词： Discovery system Digital libraries Visualization Concept space Web services

Improved Feistel-based ciphers for wireless sensor network security

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第8期9卷 1111-1117页

作者： tamara PAZYNYUK George S. OREKU Department of Computer Science and Engineering Harbin Institute of TechnologyHarbin 150006 China

Wireless sensor networks (WSNs) are exposed to a variety of attacks. The quality and complexity of attacks are rising day by day. The proposed work aims at showing how the complexity of modern attacks is growing accordingly, leading to a similar rise in methods of resistance. Limitations in computational and battery power in sensor nodes are constraints on the diversity of security mechanisms. We must apply only suitable mechanisms to WSN where our approach was motivated by the application of an improved Feistel scheme. The modified accelerated-cipher design uses data-dependent permutations, and can be used for fast hardware, firmware, software and WSN encryption systems. The approach presented showed that ciphers using this approach are less likely to suffer intrusion of differential cryptanalysis than currently used popular WSN ciphers like DES, Camellia and so on.

关键词： Security Cipher Wireless sensor network (WSN) Feistel scheme

Inventory of unintentional POPs emission from anthropogenic sources in Antarctica

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Advances in Polar Science 2022年第2期33卷 156-166页

作者： Sergey KAKAREKA tamara KUKHARCHYK Institute for Nature Management National Academy of Sciences of Belarus-Laboratory on Transboundary PollutionSkoriny 10 Minsk 220076Belarus

In spite of remote location and very limited human activities,Antarctica is affected by persistent organic pollutants(POPs).POPs investigation in Antarctica has a comparatively long history,but there are still large knowledge gaps in assessment of their emission into *** the paper the results of the first inventory of unintentional POPs emission from anthropogenic sources in Antarctica for modern period and preliminary estimate for the late 1980s are *** of dioxin/furans(PCDD/Fs)emission in different media,as well as polychlorinated biphenyls(PCBs)and hexachlorobenzene(HCB)in air is based on methodology of emission factors and indicators of human *** following sources of POPs emission have been estimated:power generation and heating,waste incineration,mobile sources and open burning of waste(in the past).According to the data obtained,annual PCDD/Fs air emission for modern period comprises 60.74 mg toxic equivalent(TEQ),PCBs-5.09 mg TEQ,and HCB-457.6 *** 2.5 mg TEQ of dioxin/furans is released to residues,so total PCDD/Fs emission is amounted 63.23 mg *** incineration makes the greatest contribution to POPs emission(96% of PCDD/Fs,98%of PCBs and 36% of HCB air emission).In late 1980s open burning of waste was the major source of *** assessment shows that over a 30-year period air emissions of PCDD/Fs decreased about 13 times,PCBs-15 times and HCB-57 times,primarily due to the prohibition of open burning of waste in compliance with the Protocol on Environmental Protection to the Antarctic Treaty requirements.

关键词： persistent organic pollutants emission inventory PCDD/Fs PCBs HCB

New insights into the regulation of cholesterol eft from the sperm membrane

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Asian Journal of Andrology 2015年第4期17卷 561-567页

作者： tamara Leahy Bart M Gadella Faculty of Veterinary Science University of Sydney 2006 Sydney Australia Department of Farm Animal Health and of Biochemistry and Cell Biology Faculty ofVeterinary Medicine Utrecht University Yalelaan 2 3584 CM Utrecht The Netherlands.

Cholesterol is an essential component of the mammalian plasma membrane because it promotes membrane stability without comprising membrane fluidity. Given this important cellular role, cholesterol levels are tightly controlled at multiple levels. It has been clearly shown that cholesterol redistribution and depletion from the sperm membrane is a key part of the spermatozoon＇s preparation for fertilization. Some factors that regulate these events are described （e.g., bicarbonate, calcium） but the mechanisms underlying cholesterol export are poorly understood. How does a hydrophobic cholesterol molecule inserted in the sperm plasma membrane enter the energetically unfavorable aqueous surroundings？ This review will provide an overview of knowledge in this area and highlight our gaps in understanding. The overall aim is to better understand cholesterol redistribution in the sperm plasma membrane, its relation to the possible activation of a cholesterol transporter and the role of cholesterol acceptors. Armed with such knowledlze, sl）erm handlin~ techniques can be adapted to better prepare spermatozoa for in vitro and in vivo fertilization.

关键词： ATP binding cassette transporters albumin high-density lipoprotein lipid rafts membrane fluidity membranemicrodomains membrane packing oxysterols reverse cholesterol transport sterol transporters

On the criteria to create a susceptibility map to debris flow at a regional scale using Flow-R

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Journal of Mountain Science 2017年第4期14卷 621-635页

作者： PASTORELLO Roberta MICHELINI tamara D'AGOSTINO Vincenzo Department of Land EnvironmentAgriculture and Forestry(TeSAF)University of Padova35020 LegnaroItaly

Studies on susceptibility to debris flows at regional scale （ioo-looo km2） are important for the protection and management of mountain areas. To reach this objective, routing models, mainly based on land topography, can be used to predict susceptible areas rapidly while necessitating few input data. In this research, Flow-R model is implemented to create the susceptibility map for the debris flow of the Vizze Valley （BZ, North-Eastern Italy; 134 km^2）. The analysis considers the model application at local scale for three sub-catchments and then it explores the model upsealing at the regional scale by verifying two methods to generate the source areas of debris-flow initiation. Using data of an extreme event occurred in the Vizze Valley （4 August 2012） and historical information, the modeling verification highlights that the propagation parameters are relatively simple to set in order to obtain correct runout distances. A double DTM filtering - using a threshold for the upslope contributing area （0.1 km^2） and a threshold for the terrain-slope angle （15°） provides a satisfactory prediction of source areas and susceptibility map within the geological conditions of the Vizze Valley.

关键词： Debris flow Susceptibility map Flow-R Triggering areas Regional scale Alpine valley

Stop flow lithography synthesis of non-spherical metal oxide particles

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Particuology 2014年第3期12卷 91-97页

作者： David Baah Tobias Donnell Julaunica Tigner tamara Floyd-Smith Materials Science & Engineering Department Tuskegee UniversityTuskegeeAL 36088USA Chemical Engineering Department Tuskegee UniversityTuskegeeAL 36088USA

Non-spherical micron and hand-sized particles and their composites have become essential in select application areas of optics, wear resistance, personnel protection, chemical mechanical polishing, and biomedicine. In this paper, the synthesis of composite and ceramic non-spherical particles using stop flow lithography is reported. Precursor suspensions of poly（ethylene glycol） diacrylate, 2-hydroxy- 2-methylpropiophenone and SiO2 or Al2O3 are prepared. The precursor suspension flows through a microfluidic device mounted on an upright microscope and is polymerized in an automated process. A photomask patterned with transparent geometric features, which define the cross-sectional shapes of the particles, masks the UV light to synthesize micron sized particles. Particles with axial dimensions ranging from 35 to 167μm were synthesized. Control of device channel depth and objective lens magnification enables the manipulation of the particle size. Composite particles in triangular, square, pentagonal, hexagonal, and circular cross sections were synthesized. Subsequently, the transformation of the composite particles into the corresponding metal oxide particles was achieved through polymer burn-offand sintering.

关键词： Microfluidics Stop flow lithography Electron microscopy

Ad libitum water consumption prevents exercise-associated hyponatremia and protects against dehydration in soldiers performing a 40-km route-march

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Military Medical Research 2019年第3期6卷 201-207页

作者： Heinrich WNolte Kim Nolte tamara Hew-Butler Movement Physiology Research Laboratory School of PhysiologyFaculty of Health SciencesUniversity of the WitwatersrandJohannesburgSouth Africa Division Biokinetics and Sport Science Department of PhysiologyUniversity of PretoriaPretoriaSouth Africa Division of Kinesiology Wayne State UniversityDetroitMIUSA.

Background: It remains unclear if ad libitum water drinking, as a hydration strategy, prevents exercise-associated hyponatremia(EAH) during prolonged exercise. The aim of this study was to determine the incidence of EAH within the broader context of fluid regulation among soldiers performing a 40-km route-march ingesting water ad ***: Twenty-eight healthy male soldiers participated in this observational trial. Pre-and post-exercise body mass, blood and urine samples were collected. Blood samples were assessed for serum sodium([Na+]), glucose, creatinine, urea nitrogen(BUN), plasma osmolality, creatine kinase(CK), and plasma arginine vasopressin(AVP) concentrations. Plasma volume(PV) was calculated using hematocrit and hemoglobin. Urine samples were analyzed for osmolality and (Na+)Water intake was assessed by weighing bottles before, during and after the march. The mean relative humidity was 55.7%(21.9–94.3%) and the mean dry bulb temperature was 27.1°C(19.5°C-37.0°C) during the ***: Twenty-five soldiers(72±10 kg)(Mean±SD) completed the march in 09:11±00:43(hr:min). Participants consumed 736±259 ml/h of water and lost 2.8±0.9 kg(4.0%±1.4%, P<0.05) of body mass. Significant(pre-march vs. post-march;P<0.05) decreases in serum [Na+](141 mmol/L vs. 136 mmol/L), plasma osmolality(303 m Osmol/kg H2O vs. 298 m Osmol/kg H2O), and serum creatinine(111 μmol/L vs. 101 μmol/L) and urine [Na+](168 mmol/L vs. 142 mmol/L), as well as significant increases in plasma AVP(2 pg/ml vs. 11 pg/ml), plasma CK(1423 U/L vs. 3894 U/L) and urine osmolality(1035 m Osmol/kg H2O vs. 1097 m Osmol/kg H2O) were found. The soldier(72 kg) with the lowest postexercise sodium level completed the march in 08:38. He drank 800 ml/h, lost 2% body mass, and demonstrated(prepost) increases in plasma osmolality(294–314 m Osmol/kg H2O), BUN(20–30 mg/dl), AVP(2–16 pg/ml) and PV(41%). His urine osmolality decreased from 1114 m Osmol/kg H2O to 1110 m Osmol/kg H2O. No participants finished

关键词： Serum sodium concentration Exercise-associated hyponatremia Arginine vasopressin Fluid balance Electrolyte balance Military