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Species Diversity,Distribution,and microhabitats of Anurans on ***-Kalo of the *** Range Natural Park,Bukidnon,Philippines

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Asian herpetological Research 2021年第1期12卷 58-75页

作者： Von Carlo P.DELA TORRE olga m.NUNEZA Department of Biological Sciences and Environmental Studies University of the Philippines MindanaoMintal.Tugbok District.Davao City 8022Philippines Wildlife-Human Interaction Studies Ecological Researchand Biodiversity Conservation Laboraory.University of the PhilippinesMindanaoMintalTugbok DistrictDavao City 8022Philippines Department of Biological Sciences and Biodiversity Laboratory Premier Research lnstitute of Science and MathematicsMindanaoState University-lligan Institute of TechnologyA.Bonifacio Avelligan City 9200Philippines

Anurans are considered good indicators of habitat quality due to their bi-phasic life mode,limited dispersal abilities,and sensitivity to environmental changes brought about by habitat fragmentation,pollution,climate change,and emerging infectious *** study aimed to determine species diversity and local distribution of anurans in lower(1000–1400 masl)and upper(1400–1600 masl)montane forests on ***-Kalo of the *** Range Natural Park,Central mindanao,Southern Philippines by employing standard sampling techniques for *** recorded a total of 251 individual anurans,representing 12 species during a brief recent study ***-Kalo’s upper montane forest has a higher diversity index(H’=1.276)than the lower montane forest(H’=0.851).Despite the very low diversity indices,the level of endemism of anurans was 100%where ten of the recorded species are mindanao Faunal Region endemics and an additional two species are Philippine *** muelleri exhibited the highest local abundance and individuals of this species which constituted 73%of individual anurans *** of the species encountered prefer terrestrial and aquatic microhabitats,specifically on the rocks and bank substrates along the rivers and *** species of anurans(Philautus acutirostris,***,and Rhacophorus bimaculatus)were strictly found in arboreal *** magnus and *** have overlapping *** indicate that for such a short survey and modest sampling effort,the lower and upper montane forests of ***-Kalo support high endemism of anuran species suggesting that conservation efforts continue to be a priority in this unique protected area.

关键词： conservation endemic indicator species montane forest protected area

INITIAL VALUE TECHNIQUES FOR The he.mHOLTZ AND mAXWELL EQUATIONS

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Journal of Computational mathematics 2007年第3期25卷 368-373页

作者： Frank Natterer olga Klyubina Department of mathematics University of MünsterGermany

We study the initial value problem of the he.mholtz equation with spatially variable wave number. We show that it can be stabilized by suppressing the evanescent waves. The stabilized he.mholtz equation can be solved numerically by a marching scheme combined with FFT. The resulting algorithm has complexity n^2 log n on a n x n grid. We demonstrate the efficacy of the.method by numerical examples with caustics. For the.maxwell equation the same treatment is possible after reducing it to a second order system. We show how the.method can be used for inverse problems arising in acoustic tomography and microwave imaging.

关键词： Stability of elliptic initial value problems Parabolic wave equation Inverseproblems in acoustics and electromagnetics.

Land use in agricultural landscapes with chernozems contaminated after Chernobyl accident: Can we be confident in radioecological safety of plant foodstuff?

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International Soil and Water Conservation Research 2019年第2期7卷 158-166页

作者： olga Komissarova Tatiana Paramonova Radioecology&Ecotoxicology Department Soil Science FacultyLomonosov Moscow State UniversityLeninskie Gory 1-12Moscow 119991Russia

Agricultural land use in the area of the post-Chemobyl Plavsk radioactive hotspot (Tula region,Central Russia) has raised a problem of radioecological safety of obtained plant *** of 137Cs activities and inventories in components of 'soil-plant' systems of the territory has been conducted in 2014-2017 in 10 agrosystems and 2 semi-natural *** was revealed that density of 137Cs contamination of arable chernozems and alluvial calcareous soils nowadays varies in a range 140-220 kBq/m2 and exceeds radiation safety standard by^3.5-6 *** plowing of the arable soils up to 30-cm in 1986-1987 resulted in decreasing of 137Cs inventories in rooting zone by ≈ 70% for crops cultivated with shallow disk plowing (wheat,barley),and by ≈ 35% for crops cultivated with middle plowing (buckwheat,amaranth,white mustard).The investigated plants and their compartments can be grouped on the basis of transfer factor values as follows:maize (stems and leaves)> amaranth> bromegrass > vegetation of dry meadow,galega,sunflower (seeds),vegetation of wet meadow > maize (grain),soybean (pods),barley (grain),buckwheat (grain),potatoes (tubers)> white mustard (seeds),wheat (grain).It is noticeable that generative plant compartments are characterized by less 137Cs activities in comparison with stems and leaves;and that 137Cs root uptake is not coincide with total flux of mineral nutrients in 'soil-plant' *** sum,137Cs soil-to-plant transfer in the area of the Plavsk radioactive hotspot is characterized by considerable discrimination,so 137Cs activities in plants are completely in accordance with national standards.

关键词： Radioactive soil contamination Caesium-137 137Cs Arable soils 'Soil-plant' system Chernobyl accident Radioecologically safe land use

Parabolic Trough Collector and Central Receiver Coupled with Fresnel Lens:Experimental Tests

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International Journal of Automation and computing 2020年第4期17卷 572-587页

作者： Angelica Palacios Dario Amaya olga Ramos Universidad militar Nueva Granada Bogota 110121Colombia

Renewable energies have a high impact on power energy production and reduction of environmental pollution worldwide,so high efforts have been made to improve renewable technologies and research about *** paper presents the the.mal performance results obtained by simulation and experimental tests of a parabolic trough collector with central receiver coupled to Fresnel lens,under different configurations on the *** simulation method was computational fluid dynamics(CFD)analysis in SolidWorks(R)soft-ware tool,which works with Naiver-Stokes equations to converge on a *** tests were formed with all configurations proposed and three observations for each one,a total of 12 observations were performed in all *** a result,the best the.mal performance in simulation was achieved with the Fresnel lens and black pipe collector,with a maximum temperature of 116℃under 1000 W/m^2 radiation,the same system achieved in experimental tests a maximum temperature of 96℃with a radiation of 983 W/m^2.

关键词： Solar collector parabolic trough collector Fresnel lens the.mal conductivity solar power

Controlled Wettability of Polymers via Environmental Crazing

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Chinese Journal of Polymer Science 2022年第10期40卷 1307-1314,I0012页

作者： Alena Yu.Yarysheva Larisa m.Yarysheva Fedor V.Drozdov olga V.Arzhakova Aziz m.muzafarov Faculty of Chemistry Lomonosov Moscow State UniversityLeninskieGory 1-3Moscow 119991Russia Institute of Synthetic Polymer materials RAS ul.Profsoyuznaya 70Moscow 117393Rusia

This work highlights the benefits of environmental crazing for the control over the hydrophilic-lipophilic balance of glassy amorphous and semicrystalline polymers:poly(ethylene terephthalate)(PET)and biodegradable polycaprolactone(PCL).Task-oriented encapsulation of diverse commercial and natural hydrophilic(polyethyleneoxide,polyvinylpyrrolidone,gelatin)and hydrophobic guest additives(perfluoroorgano siloxanes,water-repellent impregnation)into mesoporous host polymer(PET,PCL)matrixes allows targeted control over the wettability of the resultant nanocomposite *** on the nature of the guest additive,the properties of the.modified polymers can be varied from hydrophilic to hydrophobic:contact angle(CA)of PET can be adjusted from 47_(⊥)/38_(||)to 130_(⊥)/117_(||)°(for initial PET,CA=82°)and CA of PCL from 40°to 114°(for initial PCL CA=75°).The unique benefits of environmental crazing for structural modification are related to the universal character of this approach which can be applied to a broad range of polymers and allows preparation of diverse high-performance materials with tunable hydrophilic-lipophilic balance.

关键词： Wettability Hydrophilic-hydrophobic balance Contact angle Environmental crazing Poly(ethylene terephthalate) Polycaprolactone

Evolutionary status of T Tauri stars

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Research in Astronomy and Astrophysics 2018年第8期18卷 103-110页

作者： olga Eretnova Alexander Dudorov Physics Department Chelyabinsk State University

The problem of determining the.masses and ages of T Tauri star （TTS） using their evolu- tionary status is discussed. We test four pre-main sequence evolutionary models using well determined observational parameters of 12 binary TTSs and two binary red dwarfs. It is shown that the.masses derived using the tracks of all models are in good agreement with flhe.masses obtained from the obser- vations of TTSs with masses m 〉 0.7 me （mean error ε,- 10%）. Low-mass stars with m ≤ 0.7 m⊙ have significantly greater mean error; e - 50% for the tracks of Bressan et al. and Chen et al., and e - 30% for the other tracks. The isochrones of all tested evolutionary models diverge for stars with masses m ≤ 0.7 m⊙. The difference increases with the.mass decrease and can reach 10% of Kelvin- he.mholtz time for stars with mass m = 0.2 me. The ages of most of the considered TTSs are smaller than the Kelvin-he.mholtz time. This confirms their evolutionary status of being pre-main sequence stars.

关键词： stars pre-main sequence stars - stars binaries - hertzsprung-Russell diagram

Dynamics and genesis of calcic accumulations in soils and sediments of the Argentinean Pampa

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International Journal of Sediment Research 2015年第3期30卷 179-189页

作者： Alsu Kuznetsova olga Khokhlova Department of Renewable resources University of Alberta Edmonton Institute of Physicochemical and Biological Problems of Soil Science RAS Puschino

micromorphology of calcic accumulations(calcite,whewellite and gypsum) and geochemical indices were considered as indicators of genesis and evolution of pedogenic accumulations in soils and paleosediments of the Argentinean *** groups of separate and independent calcic accumulations were studied using scanning electron microscopy:(i) in situ Argiudolls,reflecting the current soil formation;(ii) in the layers of calcrete(locally named tosca).reflecting the past environments and conditions of these layers *** pedogenic gypsum accumulations in Argiudolls were described and possible ways of their formation were *** analyses of morphology of carbonate accumulations and geochemical indices in different horizons of Argiudolls and layers of tosca showed that the tosca is paleopedocomplex with complicated formation *** of current environment on tosca morphology is absent,so it is possible to use these pedofeatures for paleoreconstructions in further studying.

关键词： Carbonate accumulations Gypsum accumulations Pedogenic rhizoliths Tosca

3D model of Svecofennian Accretionary Orogen and Karelia Craton based on geology,reflection seismics,magnetotellurics and density modelling:Geodynamic speculations

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Geoscience Frontiers 2020年第3期11卷 999-1023页

作者： michael V.mints Victor N.Glaznev olga m.muravina Elena Yu Sokolova Geological Institute RASMoscowRussia Voronezh State University VoronezhRussia Schmidt Institute of Physics of the Earth RASMoscowRussia All-Russian Research Geological Oil Institute MoscowRussia

A 3D model of deep crustal structure of the Archaean Karelia Craton and late Palaeoproterozoic Svecofennian Accretionary Orogen including the boundary zone is *** model is based on the combination of data from geological mapping and reflection seismic studies,along profiles 1-EU,4 B,FIRE-1-2 a-2 and FIRE-3-3 a,and uses results of magnetotelluric soundings in southern Finland and northern Karelia.A seismogeological model of the crust and crust-mantle boundary is compared with a model of subhorizontal velocity-density layering of the *** TTG-type crust of the Palaeoarchaean and mesoarchaean microcontinents within the Karelia Craton and the Belomorian Province are separated by gently dipping greenstone belts,at least some of which are *** structure of the crust was determined mainly by Palaeoproterozoic tectonism in the intracontinental settings modified by a strong collisional compression at the end of the *** insights into structure,origin and evolution of the Svecofennian Orogen are *** accretionary complex is characterized by inclined tectonic layering:the tectonic sheets,~15 km thick,are composed of volcanic-sedimentary rocks,including electro-conductive graphite-bearing sedimentary rocks,and electro-resistive granitoids,which plunge monotonously and consecutively *** reaching the level of the lower crust,the tectonic sheets of the accretionary complex lose their distinct *** the seismic reflection pattern they are replaced by a uniform acoustically translucent medium,where separate sheets can only be traced *** crust-mantle boundary bears a diffuse character:the transition from crust to mantle is recorded by the disappearance of the vaguely drawn boundaries of the tectonic sheets and in the gradual transition of acoustically homogeneous and translucent lower crust into transparent *** the effect of endogenic heat flow,the accretionary complex underwent high-temperatu

关键词： Reflection seismics magnetotellurics Svecofennian accretionary Orogen Svecofennian Ocean 3D crustal model Velocity-density layering

On the winter enhancement of adaptive humoral immunity: hypothesis testing in desert hamsters (Phodopus roborovskii: Cricetidae, Rodentia) kept under long-day and short-day photoperiod

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Integrative Zoology 2020年第3期15卷 232-247页

作者： Nina Yu.VASILIEVA Anastasiya m.KHRUSHCHOVA Alexander V.KUPTSOV olga N.SheKAROVA olga V.SOKOLOVA Dehua WANG Konstantin A.ROGOVIN Severtsov Institute of Ecology and Evolution RAS MoscowRussia Institute of Zoology Chinese Academy of Science Chaoyang DistrictBeijingChina

We tested the winter immunity enhancement hypothesis(WIEH)on male desert hamsters(Phodopus roborovskii)kept under long-day(LD)and short-day(SD)*** assumed that under SD in a laboratory,the adaptive humoral immune responsiveness to the antigenic challenge would be enhanced due to the lack of winter physical stressors and food shortages and/or because of the action of an endogenous winter bolstering mechanism,while under LD the immune responsiveness would be suppressed by the activity of the reproductive *** results support the WIEH in *** did not find a difference in antibody production in response to sheep erythrocytes between SD and LD hamsters,but SD males had the lower number of granulocytes and the higher number of lymphocytes in white blood cell *** activity was lower in SD *** males demonstrated an increase in their mass-specific resting metabolic rate,their mass-specific maximal metabolic rate and their level of *** result of a generalized linear model analysis indicates the negative effect on secondary immunoresponsiveness to sheep erythrocytes of mid-ventral gland size,the organ characterizing individual reproductive quality,and designates a tradeoff between antibody production and reproductive *** mass-independent maximal metabolic rate also negatively affected antibody production,indicating a tradeoff between maximal aerobic performance and the adaptive immune *** higher stress in SD males seems to be the.most likely reason for the lack of the effect of daylight duration on antibody production.

关键词： adaptive humoral immunity desert hamster photoperiodicity winter immunoenhancement