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

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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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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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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Galvanic and asymmetry effects on the local electrochemical behavior of the 2098-T351 alloy welded by friction stir welding

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Journal of Materials Science & Technology 2020年第10期42卷 162-175页

作者： Mariana X.Milagre Uyime Donatus naga V.Mogili Rejane Maria PSilva Barbara victoria Gde Viveiros victor F.Pereira Renato A.Antunes Caruline S.CMachado Joao victor S.Araujo Isolda Costa Instituto de Pesquisas Energeticas e nucleares IPEN/CNENAv.Prof.Lineu Prestes2242Sao PauloBrazil Laboratorio nacional de nanotecnologia LNNano/CNPENRua Giuseppe Maximo Scolfaro10.000Polo II deAlta Tecnologia de CampinasBrazil Centro de Engenharia Modelagem e Ciencias Sociais AplicadasUFABCAv.dos Estados 5001Santo AndreBrazil

Scanning electrochemical microscopy(SECM)and scanning vibrating electrode technique(SVET)were used to investigate the electrochemical behaviour of the top surface of the 2098-T351 alloy welded by friction stir welding(FSW).The SVET technique was efficient in identifying the cathodic and anodic weld *** welding joint(WJ),which comprises the thermomechanically affected zone(TMAZ)and the stir zone(SZ),was cathodic relative to the heated affected zone(HAZ)and the base metal(BM).The reactivities of the welding joint at the advancing side(AS)and the retreating side(RS)were analyzed and compared using SECM technique in the competition mode by monitoring the dissolved oxygen as a redox mediator in 0.005 mol L^-1 naCl *** RS was more electrochemically active than the AS,and these results were correlated with the microstructural features of the welded alloy.

关键词： Aluminum alloys Friction stir welding Localized corrosion

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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

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Plasma glial fibrillary acidic protein and neurofilament light chain for the diagnostic and prognostic evaluation of frontotemporal dementia

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Translational neurodegeneration 2021年第4期10卷 666-677页

作者： nuole Zhu Miguel Santos-Santos Ignacio lllán-Gala victor Montal Teresa Estellés Isabel Barroeta Miren Altuna Javier Arranz Laia Muñoz Olivia Belbin Isabel Sala Maria Belén Sánchez-Saudinós Andrea Subirana Laura Videla Jordi Pegueroles Rafael Blesa Jordi Clarimón Maria Carmona-Iragui Juan Fortea Alberto Lleó Daniel Alcolea Sant Pau Memory Unit Department of NeurologyInstitut d'Investigacions Biomèdiques Sant Pau-Hospital de Sant PauUniversitat Autònoma de Barcelona08041 BarcelonaSpain Centro de Investigación Biomédica en Red en Enfermedades neurodegenerativas(CIBERnED) 28031 MadridSpain Autonomous University of Barcelona 08913 BarcelonaSpain Fundación Catalana Sindrome de Down Centre Mèdic Down08029 BarcelonaSpain

Background:Astrocytes play an essential role in neuroinflammation and are involved in the pathogenesis of neurodenegerative *** of glial fibrillary acidic protein(GFAP),an astrocytic damage marker,may help advance our understanding of different neurodegenerative *** this study,we investigated the diagnostic performance of plasma GFAP(pGFAP),plasma neurofilament light chain(pnfL)and their combination for frontotemporal dementia(FTD)and Alzheimer's disease(AD)and their clinical utility in predicting disease ***:pGFAP and pnfL concentrations were measured in 72 FTD,56 AD and 83 cognitively normal(Cn)participants using the Single Molecule Array *** the 211 participants,199 underwent cerebrospinal(CSF)analysis and 122 had magnetic resonance *** compared cross-sectional biomarker levels between groups,studied their diagnostic performance and assessed correlation between CSF biomarkers,cognitive performance and cortical *** prognostic performance was investigated,analyzing cognitive decline through group comparisons by ***:Unlike pnfL,which was increased similarly in both clinical groups,pGFAP was increased in FTD but lower than in AD(all Pnation of both plasma markers improved the diagnostic performance to discriminate FTD from AD(area under the curve[AUC]:combination 0.78;pGFAP 0.7;pnfL 0.61,all Pn FTD,pGFAP correlated with cognition,CSF and plasma nfL,and cortical thickness(all Pnge in MMSE score and poor cognitive outcome during follow-up both in FTD(1.40 points annually,hazard ratio[HR]3.82,Pnd in AD(1.20 points annually,HR 2.26,Pnclusions:pGFAP and pnfL levels differ in FTD and AD;and their combination is useful for distinguishing between the two *** could also be used to track disease severity and predict greater cognitive decline during follow-up in patients with FTD.

关键词： Glial fibrillary acidic protein neurofilament Frontotemporal dementia Plasma biomarkers

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