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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

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

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.

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

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

A phase inversion polymer coating to prevent swelling and spalling of clay fines in coal seam gas wells

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International Journal of Coal science & Technology 2018年第2期5卷 179-190页

作者： Lei Ge Christopher Hamilton Rahmah Tasha Febrina victor Rudolph Thomas E. Rufford school of Chemical Engineering The University of Queensland Saint Lucia QLD 4072 Australia Centre for Future Materials University of Southern Queensland Springfield Central QLD 4300 Australia

We report a phase inversion polymer coating as a novel concept with potential to prevent clay swelling and fines generation in coal seam gas, or other petroleum, wellbores. Our approach uses polyethersulfone （PEs） with n-methyl-2- pyrrolidone （nMP） as a water-soluble solvent to form a dense, low-porosity film across the clay-rich interburden layers, but a porous and permeable membrane on coal seams. This contrasting behaviour occurs because the coal contains much more free water than the clay-rich interburden layers. We demonstrate the efficacy of the method to prevent clay spalling in immersion tests and under a flow of fresh water in a visual swell test apparatus. The clay-rich rocks studied were mudstone and siltstone, and these were dip coated in the PEs/nMP solution. The uncoated mudstone swelled and broke apart quickly in the immersion test and visual flow test, but the PEs coated rock samples were stable for 30 days. The coated rock and coal samples were characterised by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. The morphology of coated mudstone and coated coal samples showed that the polymer formed a dense layer across the low-permeability mudstone, but an open porous structure on the coal surface. The effect of the coating on the permeability of KCl brine through coal was measured in a core-flood apparatus. Although the permeability of the coal showed some deterioration after coating, from （0.58 ± 0.12） mD to （0.3 ±0.03） mD, these results demonstrate the potential of a smart polymer coating to prevent clay swelling while remaining permeable to gas and water on coal layers.

关键词： Coal bed methane Formation damage smectite Wellbore stability

Virtual Transmission solution Based on Battery Energy storage systems to Boost Transmission Capacity

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Journal of Modern Power systems and Clean Energy 2024年第2期12卷 466-474页

作者： Matías Agüero Jaime Peralta Eugenio Quintana victor Velar Anton stepanov Hossein Ashourian Jean Mahseredjian Roberto Cárdenas Coordinador Eléctrico nacional SantiagoChile PGsTech Montreal Canada Ecole Polytechnique de Montréal Montréal Canada University of Chile Santiago Chile IEEE

The increasing penetration of variable renewable energy(VRE)generation along with the decommissioning of conventional power plants in Chile,has raised several operational challenges in the Chilean national Power Grid(nPG),including transmission congestion and VRE *** mitigate these limitations,an innovative virtual transmission solution based on battery energy storage systems(BEsss),known as grid booster(GB),has been proposed to increase the capacity of the main 500 kV corridor of the *** paper analyzes the dynamic performance of the GB using a wide-area electromagnetic transient(EMT)model of the *** GB project,composed of two 500 MVA BEss units at each extreme of the 500 kV corridor,allows increasing the transmission capacity for 15 min during n-1 contingencies,overcoming transmission limitations under normal operation conditions while maintaining system stability during *** dynamic behavior of the GB is also analyzed to control power flow as well as voltage *** results show that the GB is an effective solution to allow greater penetration of VRE generation while maintaining system stability in the nPG.

关键词： Battery energy storage system(BEss) grid booster transient stability voltage stability electromagnetic transient(EMT)

Coffee Leaf Rust(Hemileia vastatrix)Disease in Coffee Plants and Perspectives by the Disease Control

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 923-949页

作者： Alexis salazar-navarro victor Ruiz-Valdiviezo Jose Joya-Dávila Daniel Gonzalez-Mendoza Instituto de Ciencias Agrícolas de la Universidad Autónoma de Baja California(ICA-UABC) Nuevo LeónBaja California21705México Laboratorio de Biología Molecular del Instituto Tecnológico nacional de Tuxtla Gutierrez(TecnM) Tuxtla GutierrezChiapas29050México Facultad de Ciencias Agronómicas Campus V.Universidad Autónoma de Chiapas(UnACH) VillafloresChiapas30470México

Coffee Leaf Rust(CLR)is caused by Hemileia vastatrix in Coffea *** is one of the most dangerous phytopathogens for coffee plantations in terms of coffee productivity and coffee cup *** this review,we resume the problem of CLR in Mexico and the pathogenesis of *** review abord plant-pathogen interactions which lead a compatible or incompatible interactions and result in CLR disease or resistance,*** review abord Coffea *** response pathways involved in *** ***,current measures to control *** proliferation and germination were aborded focused on phytosanitary actions,and biological and chemical ***,new trendlines to reduce the impact of CLR as nanoparticles and nanotechnology were analyzed.

关键词： Coffee leaf rust Coffea arabica pathogenesis nanoparticles biological control

Resolving the inner jet of PKs 1749+096 with super-resolution VLBA images at 7 mm

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Research in Astronomy and Astrophysics 2021年第4期21卷 202-206页

作者： Lang Cui Ru-sen Lu Wei Yu Jun Liu victor M.Patino-Alvarez Qi Yuan Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Max Planck Institute for Radio Astronomy Auf dem hiigel 69Bonn 53121Germany Instituto nacional de Astroffsica Optica y ElectronicaLuis Enrique Erro#1TonantzintlaPuebla 72840Mexico University of Chinese Academy of sciences Beijing 100049China

High resolution imaging of inner jets in Active Galactic nuclei(AGns)with Very Long Baseline Interferometry(VLBI)at millimeter wavelengths provides deep insight into the launching and collimation mechanisms of relativistic *** BL Lac object,PKs 1749+096,shows a core-dominated jet pointing toward the northeast on parsec-scales revealed by various VLBI *** order to investigate the jet kinematics,in particular,the orientation of the inner jet on the smallest accessible scales and the basic physical conditions of the core,in this work we adopted a super-resolution technique,the Bi-spectrum Maximum Entropy Method(BsMEM),to reanalyze VLBI images based on the Very Long Baseline Array(VLBA)observations of PKs 1749+096 within the VLBA-BU-BLAZAR 7 mm monitoring *** observations include a total of 105 epochs covering the period from 2009 to *** found that the stacked image of the inner jet is limb-brightened with an apparent opening angle of 50°.0±8°.0 and 42°.0±6°.0 at the distances of 0.2 and 0.3 mas(0.9 and 1.4 pc)from the core,corresponding to an intrinsic jet opening angle of 5°.2±1°.0 and 4°.3±0°.7,*** addition,our images show a clear jet position angle swing in PKs 1749+096 within the last ten *** discuss the possible implications of jet limb brightening and the connection of the position angle with jet peak flux density and gamma-ray brightness.

关键词： galaxies:quasars:individual:PKs 1749+096 galaxies:jets radio continuum:galaxies