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natural history of Valentin’s rock lizard(Darevskia valentini) in Armenia

Zoological Research 2019年第4期40卷 277-292页

作者： Eduard Galoyan Alisa Bolshakova Manush Abrahamyan Ruzanna Petrosyan Valeria Komarova victor Spangenberg Marine Arakelyan Zoological Museum of the Lomonosov Moscow State University Moscow 125009Russia Department of Zoology Biological Faculty of Moscow State UniversityMoscow 119992Russia Department of Zoology Biological Faculty of Yerevan State UniversityYerevan 0025Armenia Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences Moscow 119071Russia Vavilov Institute of General Genetics Russian Academy of SciencesMoscow 119991Russia

Valentin's rock lizard (Darevskia valentini) is suggested to be the pare nt for several parthenoge netic species (e.g., D. armeniaca, D. bendimahiensis, D. sapphirina, and D. unisexualis) that evolved through hybridization. Complex evolutionary processes (ineluding reticulate evolution) are occurring within the areas where Valentin' s rock lizard coexists with these and other rock lizards. Hence, a detailed biological specification of this species is important for understanding how vertebrates evolve. Valentin's rock lizard is a longlived (up to 9 years), small diurnal lizard with larger females than males, which is unlike other species of the genus. Their relatively large eggs and early reproducti on period, which occurs just after emerge nee from winter shelters, are adaptatio ns for living in a high elevation climate (higher than 2 000 m a.s.l.). Their body temperatures (31 -32℃) are comparable to body temperatures of rock lizards living in milder climates, though female body temperature is more depe ndent on substrate temperature and basking due to their lower activity than that found in males. Population density fluctuates from several individuals to several hundred per hectare and is not affected by parthenogen coexistenee, although hybrids do occur in sexually biased populations where males are more common than females. The male home range is larger than that of females, though these home ranges broadly overlap. Prey is not limited in the mountain meadows and Valentin's rock lizards feed on a great variety of arthropods. Infan ticide occurs in high-de nsity populati ons.

关键词： Darevskia valentini Reproduction Population density Skeletochronology Home range Seasonal activity

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(-)-Sparteine辅助的邻位锂化反应对映选择性合成具有平面手性的非对称二茂铁胺

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有机化学 2010年第11期30卷 1754-1758页

作者：周智明袁浩 Snieckus,victor 北京理工大学化工与环境学院北京100081 Department of Chemistry Queen's University Kingston ON KL7 3N6 Canada

以非对称的n-乙基-n-异丙基-二茂铁酰胺为底物,利用(-)-sparteine辅助的邻位锂化反应制备具有平面手性的二茂铁衍生物,得到了很高的产率和对映选择性.并测定了1-(n-乙基-n-异丙基)酰胺-2-碘-二茂铁(10a)的晶体结构.研究发现,非对称的二... 详细信息

以非对称的n-乙基-n-异丙基-二茂铁酰胺为底物,利用(-)-sparteine辅助的邻位锂化反应制备具有平面手性的二茂铁衍生物,得到了很高的产率和对映选择性.并测定了1-(n-乙基-n-异丙基)酰胺-2-碘-二茂铁(10a)的晶体结构.研究发现,非对称的二茂铁底物有利于强化底物的手性环境,进而提高反应的对映选择性.

关键词： (-)-Sparteine 邻位锂化反应非对称二茂铁胺平面手性二茂铁晶体结构

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Larvicidal efficacy of plant extracts and isolated compounds from Annonaceae and Piperaceae against Aedes aegypti and Aedes albopictus

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Asian Pacific Journal of Tropical Medicine 2020年第9期13卷 384-396页

作者： Alzeir M.Rodrigues victor Emanuel P.Martins Selene M.Morais Departamento de Ensino Instituto Federal de EducaçãoCiência e Tecnologia do Ceará(IFCE)Rodovia CE 060km 332Vila Martins63.560-000 AcopiaraCearáBrazil Programa de Pós-Graduação em Biotecnologia RENORBIOUniversidade Estadual do CearáAvenida Doutor Silas Munguba170060741-000 FortalezaCearáBrazil Instituto de Ciências Exatas e da natureza Universidade da Integração Internacional da Lusofonia Afro-Brasileira(Unilab)Campus das AurorasRua JoséFranco de Oliveira s/n62790-970 RedençãoCearáBrasil Departamento de Química Universidade Estadual do CearáAvenida Doutor Silas Munguba170060741-000 FortalezaCearáBrazil

The Aedes(Ae.)aegypti and *** mosquitoes are vectors of epidemiologically relevant arboviruses in the public health context,such as the dengue,Zika and chikungunya *** the alternatives to synthetic insecticides for the control of these vectors,the use of natural plant products deserves *** review summarizes findings on the larvicidal potential of plant extracts on *** and ***,as well as the potential of isolated compounds from plants of the Annonaceae and Piperaceae families against these *** related to larvicidal activity of plant extracts and isolated compounds in Aedes *** the Web of Science database were used,for plant extracts considering publications between 2000 and 2019.A total of 859 articles were analyzed for plant extracts and estimates of lethal concentration values(LC50 and LC90).In the end,95 articles that presented the larvicidal potential of 150 plant species from 52 families were *** two families most studied for this activity were Fabaceae and Asterace *** plant families with the best LC50 values against mosquitoes were Piperaceae and *** activity of 50 acetogenins has already been identified on ***,and 29 of them presented LC50 below 10μg/mL,as well as the larvicidal activity of 8 compounds isolated from ***,plants of these two families are promising for the development of commercial botanical larvicides in the form of extracts and isolated substances,as well as the production via organic synthesis of the most active compounds.

关键词： Larvicidal activity Plant extracts Acetogenins Aedes

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Assessment of the exploitable biomass of thread herring(Opisthonema spp.)in northwestern Mexico

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Acta Oceanologica Sinica 2021年第9期40卷 53-65页

作者： Marcelino Ruiz-Dominguez Casimiro Quinonez-Velazquez Dana Isela Arizmendi-Rodriguez victor Manuel Gomez-Munoz Manuel Otilio nevarez-Martinez Facultad de Ciencias del Mar Universidad Autonoma de SinaloaMazatlan 82000Mexico Instituto Politecnico nacional Centro Interdisciplinario de Ciencias MarinasLa Paz 23000Mexico Instituto nacional de Pesca y Acuacultura Centro Regional de Investigacion Pesquera Unidad GuaymasGuaymas 85400Mexico

In recent years,the small pelagic fishery on the Pacific northwest coast of Mexico has significantly increased fishing pressure on thread herring Opisthonema *** fishery is regulated using a precautionary approach(acceptable biological catch(ABC)and minimum catch size).However,due to fishing dynamics,fish aggregation habits and increased fishing mortality,periodic biomass assessments are necessary to estimate ABC and assess the resource *** Catch-MSY approach was used to analyze historical series of thread herring catches off the western Baja California Sur(BCS,1981–2018)and the Gulf of California(GC,1972–2018)to estimate exploitable biomass and target reference points in order to obtain catch *** to the results,in GC,the maximum biomass reached in 1972(at the beginning of fishery)and minimum biomass reached in 2015;the estimated exploitable biomass for 2019 was 42.2×10^(4) t;and the maximum sustainable yield(MSY)was 15.4×10^(4) *** the western BCS coast,the maximum biomass was reached in 1981(at the beginning of fishery)and minimum biomass was reached in 2017;the estimated exploitable biomass for 2019 was 3.2×10^(4) t;and the MSY was 1.2×10^(4) *** stocks showed a decrease in biomass over the past years and were currently near to point of full *** results suggest that the use of the Catch-MSY method is suitable to obtain annual biomass estimates,in order to establish an ABC,to know the current state of the resource,and to avoid overcoming the potential recovery of the stocks.

关键词： Catch-MSY thread herring exploitable biomass estimate

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Platinum single-atom catalyst with self-adjustable valence state for large-current-density acidic water oxidation

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eScience 2022年第1期2卷 102-109页

作者： Hui Su Mikhail A.Soldatov victor Roldugin Qinghua Liu national Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei230029AnhuiPR China The Smart Materials Research Institute Southern Federal University344090Sladkova 178/24Rostov-on-DonRussia

The design of active acidic oxygen evolution reaction(OER)catalysts is of paramount importance to achieve efficient large-current-density industrial hydrogen fuel production via water ***,we develop a Pt-based catalyst with high electrochemical activity for the OER in acidic conditions under a large *** achieve this by modulating the electronic structure of Pt into a high-valence,electron-accessible Pt1^((2.4+δ)+)(δ=0-0.7)state during the *** electron-accessible Pt1^((2.4+δ)+)single-site catalyst can effectively maintain a large OER current density of 120 mA cm^(-2)for more than 12 h in 0.5 M H_(2)SO_(4) at a low overpotential of 405 mV,and it shows a high mass activity of~3350 A gmetal^(-1)at 10 mA cm^(-2) current density and 232 mV *** in situ synchrotron radiation infrared and X-ray absorption spectroscopies,we directly observe in an experiment that a key(*O)-Pt_(1)-C_(2)n_(2) intermediate is produced by the potential-driven structural optimization of square pyramidal Pt_(1)-C_(2)n_(2) moieties;this highly favors the dissociation of H_(2)O over Pt1^(2.4+δ)^(+)sites and prevents over-oxidation and dissolution of the active sites.

关键词： Oxygen evolution reaction Acidic electrolyte In situ characterization

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Landscape genetics reveals inbreeding and genetic bottlenecks in the extremely rare short-globose cacti Mammillaria pectinifera (Cactaceae) as a result of habitat fragmentation

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Plant Diversity 2017年第1期39卷 13-19页

作者： Reyna Maya-Garcia Santiago Arizaga Pablo Cuevas-Reyes Juan Manuel Penaloza-Ramirez victor Rocha Ramirez Ken Oyama Facultad de Biologia Universidad Michoacana de San Nicolas de Hidalgo Mexico Escuela nacional-de Estudios Superiores Unidad Morelia UNAM Antigua Carretera a Pdtzcuaro 8701 Colonia Ex-Hacienda de SanJose de la Huerta58190 Morelia Michoacan Mexico

Mammillaria pectinifera is an endemic, short-globose cactus species, included in the IUCn list as a threatened species with only 18 remaining populations in the Tehuacfin-Cuicatlan Valley in central Mexico. We evaluated the population genetic diversity and structure, connectivity, recent bottlenecks and population size, using nuclear microsatellites. M. pectinifera showed high genetic diversity but some evidence of heterozygote deficiency （F15）, recent bottlenecks in some populations and reductions in population size. Also, we found low population genetic differentiation and high values of connectivity for M. pectinifera, as the result of historical events of gene flow through pollen and seed dispersal. M. pectinifera occurs in sites with some degree of disturbance leading to the isolation of its populations and decreasing the levels of gene flow among them. Excessive deforestation also changes the original vegetation damaging the natural habitats. This species will become extinct if it is not properly preserved. Furthermore, this species has some ecological features that make them more vulnerable to disturbance such as a very low growth rates and long life cycles. We suggest in situ conservation to prevent the decrease of population sizes and loss of genetic diversity in the natural protected areas such as the Tehuacan-Cuicatlan Biosphere Reserve. In addition, a long-term ex situ conservation program is need to construct seed banks, and optimize seed germination and plant establishment protocols that restore disturbed habitats. Furthermore, creating a supply of living plants for trade is critical to avoid further extraction of plants from nature.

关键词： MammiUaria pectiniferanuclear SSRGenetic diversityRecent bottlenecksEffective population size

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Hypolipidemic and Antioxidative Effects of African Star Apple Juice (Chrysophylum albidum) on Rats Fed on Diets High in Cholesterol and Oil

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Food and nutrition Sciences 2016年第10期7卷 825-843页

作者： Modupe F. Bobadoye Oluwaseun O. Bamisi victor n. Enujiugha Department of Food Science and Technology Federal University of Technology Akure Nigeria

This study investigated the possible hypolipidemic and antioxidative effects of Chrysophylum albidum juice in rats fed on highcholesterol and fatty diets (HFCD). The juice was expressed, pasteurized and frozen until needed. Diets were formulated by mixing at different ratios. Bio-assay of the blends was carried out for a period of 28 days. Twenty five male rats were divided into five groups of five each: a normal diet group, a high-cholesterol diet group, a high Fat/Cholesterol diet with 3 ml of African Star Apple Juice group, a high Fat/Cholesterol diet with 6 ml of African Star Apple Juice group, and a high Fat/Cholesterol diet with 9 ml of African Star Apple Juice group. Blood serum, selected tissues and organs were collected and the serum lipid profile, organ histology and oxidative stress test were carried out at the end of the animal experimentation. The levels of total cholesterol, triglyceride, low density lipoprotein-cholesterol, very low density lipoprotein-cholesterol and artherogenic index obtained from rats treated with African star apple juice (3 ml, 6 ml and 9 ml) decreased significantly (P ≤ 0.05), compared respectively to the HFCD rats. The results also showed that treatment with African star apple (Chrysophylum albidum) positively changed plasma antioxidant enzyme activities and lipid profiles in cholesterol-fed rats, and thus may have potential hypolipidemic and antioxidant effects, and by inference, the antiatherogenic properties in male rats. African star apple (Chrysophylum albidum) juice could protect against oxidative stress linked atherosclerosis and decrease the atherogenic index, thereby supporting the local use of Chrysophylum albidum in the management of atherosclerosis and hypertensive conditions.

关键词： Chrysophyllum albidum Atherosclerosis Antioxidant Activity Hypolipidemic Effects Oxidative Stress

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In-Situ High Pressure Studies on nanocrystalline Mercury Sulphide

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Journal of Physical Science and Application 2016年第4期6卷 59-63页

作者： K. M. Freny Joy n. victor Jaya Department of Physics Jeppiaar Engineering College Chennai 600 119 India Department of Physics Anna University Chennai 600 025 India

nanocrystalline β-HgS has many technological applications and prepared by novel microwave assisted method. The structural stability was studied by in situ high pressure X-ray powder diffraction measurements. no structural transformation was observed in nano-HgS upto 15 GPa. There is a shift in transition pressure towards the higher side when compared with the bulk materials. The volume decreased with an increase of pressure.

关键词： Microwave heating mercury sulphide phase transition high pressure XRD.

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Ballistic performance of titanium-based layered composites made using blended elemental powder metallurgy and hot isostatic pressing

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Defence Technology（防务技术） 2024年第9期39卷 1-14页

作者： Pavlo Markovsky Jacek Janiszewski Dmytro Savvakin Oleksandr Stasyuk Bartosz Fikus victor Samarov Vianey Ellison Sergey V.Prikhodko G.V.Kurdyumov Institute for Metal Physics of n.A.S.of Ukraine 36Academician Vernadsky BoulevardUA-03142 KyivUkraine Jarosław Dabrowski Military University of Technology 2Gen.Sylwester Kaliski Str.00e908 Warsaw 46Poland Synertech Inc. 11711 Monarch Street Garden GroveLos AngelesCA 92841USA Department of Materials Science and Engineering University of California Los AngelesLos AngelesCA 90095USA

Metal matrix composites tiles based on Ti-6Al-4V(Ti64)alloy,reinforced with 10,20,and 40(vol%)of either TiC or TiB particles were made using press-and-sinter blended elemental powder metallurgy(BEPM)and then bonded together into 3-layer laminated plates using hot isostatic pressing(HIP).The laminates were ballistically tested and demonstrated superior *** microstructure and properties of the laminates were analyzed to determine the effect of the BEPM and HIP processing on the ballistic properties of the layered *** effect of porosity in sintered composites on further diffusion bonding of the plates during HIP is analyzed to understand the bonding features at the interfaces between different adjacent layers in the *** ballistic performance of fabricated structures was explained by a significant reduction in the residual porosity of the BEPM products by their additional processing using HIP,which provides an unprecedented increase in the hardness of the layered *** is argued that the combination of the used two technologies,BEPM and HIP is principally complimentary for the materials in question with the abilities to solve the essential problems of each used individually.

关键词： Metal matrix composites Powder metallurgy Titanium hydride powder Master alloy Titanium carbide Titanium boride Hot isostatic pressing Ballistic tests

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Changes in insomnia severity with advanced PAP therapy in patients with posttraumatic stress symptoms and comorbid sleep apnea:A retrospective,nonrandomized controlled study

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Military Medical Research 2019年第4期6卷 308-319页

作者： Barry J.Krakow natalia D.McIver Jessica J.Obando victor A.Ulibarri Sleep&Human Health Institute 6739 Academy Rd NE Ste380AlbuquerqueNM 87109USA Maimonides Sleep Arts&Sciences 6739 Academy Rd NE Ste380AlbuquerqueNM 87109USA Los Alamos Medical Center 3917 W RdLos AlamosNM 87544USA Institution:Mozaik Solutions Solana BeachCA 92075USA

Background:Sleep disorders frequently occur in posttraumatic stress disorder(PTSD)*** insomnia is a common feature of and criteria for the diagnosis of *** sleep disorder,obstructive sleep apnea(OSA),also occurs frequently in PTSD,and emerging research indicates OSA fuels chronic *** research has investigated the impact of OSA treatment on insomnia outcomes(Insomnia Severity Index,ISI)in trauma ***:OSA patients with moderately severe posttraumatic stress symptoms were studied in a retrospective chart ***-six patients who failed CPAP therapy due to expiratory pressure intolerance or complex sleep apnea or both underwent manual titration with advanced PAP modes[autobilevel(ABPAP);adaptive servo-ventilation(ASV)],which were subsequently *** use measured by objective data downloads divided the sample into three groups:compliant regular users(C-RU):n=68;subthreshold users(SC-RU):n=12;and noncompliant users(nC-MU):n=*** average follow-up was 11.89±12.22 *** and posttreatment ISI scores were analyzed to assess residual insomnia symptoms as well as cure ***:The C-RU group showed significant improvements in insomnia with very large effects compared to those in the nC-MU reference group(P=0.019).Insomnia severity significantly decreased in all three groups with large effects(C-RU,P=0.001;SC-RU,P=0.027;nC-MU,P=0.007).Hours of weekly PAP use and insomnia severity were inversely correlated(P=0.001,r=–0.321).However,residual insomnia symptoms based on established ISI cut-offs were quite common,even among the C-RU *** hoc analysis showed that several categories of sedating medications reported at baseline(hypnotics,anti-epileptic,opiates)as well as actual use of any sedating medication(prescription or nonprescription)were associated with smaller insomnia improvements than those in patients not using any sedating ***:In a retrospective,nonrandomized analysis of a selec

关键词： Insomnia Obstructive sleep apnea Complex insomnia CBT-I Posttraumatic stress symptoms CPAP Auto bi-level Adaptive servo-ventilation

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