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Stepwise magnetization reversal of geometrically tuned in diameter Ni and FeCo bi-segmented nanowire arrays

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Nano Research 2019年第7期12卷 1547-1553页

作者： Ester M. Palmero Miguel Mendez Silvia Gonzalez Cristina Bran victor Vega manuel Vazquez victor M. Prida Institute of Materials Science of Madrid (ICMM-CSIC) Madrid 28049Spain Department of Physics University of OviedoFederico Garda Lorca 18Oviedo 33007Spain Division of Permanent Magnets and Applications IMDEA NanoscienceMadrid 28049Spain

Magnetization reversal processes of hexagonal dense arrays of bi-segmented Ni and Fe50Co50 nanowires consisting of two well defined diameters (45 and 80 nm) have been *** nanowires were grown inside of tailored pores of anodic alumina templates by combined anodization,atomic layer deposition (ALD) and electrodeposition *** experiments have allowed to identify their two-step magnetization reversal process ascribed to the respective segments of different *** is concluded from the differential susceptibility observed in the hysteresis loops,contrary to those for nanowires with homogeneous *** results are also confirmed by the first-order reversal curve (FORC) distribution diagrams,where an elongation parallel to the interaction axis around two coercive field values is obtained,which is correlated to the difference in diameter of the two *** well-defined two-step magnetization reversal process through the nanowire diameter design is thought to be very useful for the advanced control of the remagnetization in arrays of magnetic multidomain systems.

关键词： Bi-segmented nanowires nickel iron cobalt alloy stepwise magnetization reversal first-order reversal curve (FORC)

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

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

Intravitreal triamcinolone acetonide： a ＂real world＂ analysis of visual acuity, pressure and outcomes

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International Journal of Ophthalmology(English edition) 2016年第5期9卷 789-791页

作者： victor manuel Villegas Aaron Samuel Gold Andrea Wildner Azeema Latiff Timothy Garrett Murray Murray Ocular Oncology and Retina Miami Florida 33143USA

Dear Sir,Triamcinolone acetonide（TA）is worldwide available therapeutic agent that is commonly used throughout *** remains a safe and important ophthalmic therapeutic agent even after the advent of angiogenesis inhib... 详细信息

关键词： IOP TA analysis of visual acuity,pressure and outcomes real world Intravitreal triamcinolone acetonide

Dynamics of ^(14)C-labelled Glucose and NH_4^+ in a Regularly Flooded Extremely Alkaline Saline Soil

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Pedosphere 2015年第2期25卷 230-239页

作者： Luc DENDOOVEN Eustacio RAMIREZ-FUENTES Rocio ALCANTARA-HERNDEZ Cesar VALENZUELA-ENCINAS Katia Berenice SANCHEZ-LOPEZ Marco LUNA-GUIDO victor manuel RUIZ-VALDIVIEZO Laboratory of Soil Ecology ABACUSCinvestavAvenida Instituto Politecnico Nacional 2508CP 07360Mexico Mexico

Flooding an extremely alkaline(pH 10.6) saline soil of the former Lake Texcoco to reduce salinity will affect the soil carbon(C)and nitrogen(N) dynamics.A laboratory incubation experiment was done to investigate how decreasing soil salt content affected dynamics of C and N in an extremely alkaline saline *** soil with electrical conductivity(EC) of 59.2 dS m^(-1) was packed in columns,and then flooded with tap water,drained freely and conditioned aerobically at 50%water holding capacity for a *** process of flooding-drainage-conditioning was repeated eight *** original soil and the soil that had undergone one,two,four and eight flooding-drainage-conditioning cycles were amended with 1000 mg glucose-^(14)C kg^(-1) soil and 200 mg NH_4^+-N kg^(-1)soil,and then incubated for 28 *** CO_2 emissions,soil microbial biomass,and soil ammonium(NE_4^+),nitrite(NO_2^-) and nitrate(NO_3^-) were monitored in the aerobic incubation of 28 *** soil EC decreased from 59.2 to 1.0 dS m^(_1) after eight floodings,and soil pH decreased from 10.6 to *** the added ^(14)C-labelled glucose,only 8%was mineralized in the original soil,while 24%in the soil flooded eight times during the 28-d *** priming effect was on average 278 mg C kg^(-1) soil after the 28-d *** microbial biomass C(mean 66 mg C kg^(-1) soil) did not change with flooding times in the unamended soil,and increased 1.4 times in the glucose-NH_4^+-amended *** immobilization and NO_2^- concentration in the aerobically incubated soil decreased with increasing flooding times,while NO_3^- concentration *** was found that flooding the Texcoco soil decreased the EC sharply,increased mineralization of glucose,stimulated nitrification,and reduced immobilization of inorganic N,but did not affect soil microbial biomass C.

关键词： C mineralization CO2 emission microbial biomass C mineral N nitrification

Greenhouse Gas Emissions and Growth of Wheat Cultivated in Soil Amended with Digestate from Biogas Production

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Pedosphere 2017年第2期27卷 318-327页

作者： Liliana PAMPILLON-GONZALEZ Marco LUNA-GUIDO victor manuel RUIZ-VALDIVIEZO Olivia FRANCO-HERNANDEZ Fabign FERNANDEZ-LUQUENO Oetavio PAREDES-LOPEZ Gerardo HERNANDEZ Luc DENDOOVEN PhD Program on Science Technology and Society Cinvestav IPN 2508 Mexico DF 07360 (Mexico) Laboratory of Soil Ecology Laboratorio de Matemdticas Aplicadas y Cdmputo de Alto Rendimiento Cinvestav-Edomex (ABACUS) Cinvestav IPN 2508 Mexico DF 07360 (Mexico) Department of Chemistry Unidad Profesional Interdisciplinaria de Biotecnologla-Instituto Politdcnico Nacional (UPIBI-IPN) Me- xico DF 07340 (Mexico) Sustainability of Natural Resources and Energy Program Cinvestav-Saltillo 1062 Coahuila 25900 (Mexico) Department of Biotechnology and Biochemistry Cinvestav Irapuato 36821 (Mexico)

Digestate, the product obtained after anaerobic digestion of organic waste for biogas production, is rich in plant nutrients and might be used to fertilize crops. Wheat （Triticum spp. L.） was fertilized with digestate, urea, or left unfertilized and cultivated in the greenhouse for 120 d. Emissions of greenhouse gasses （carbon dioxide （CO2）, methane （CH4）, and nitrous oxide （N20）） were monitored and plant growth characteristics were determined at harvest. The digestate was characterized for heavy metals, pathogens, and C and N mineralization potential in an aerobic incubation experiment. No Salmonella spp., Shigella spp., or viable eggs of helminths were detected in the digested pig slurry, but the number of faecal coliforms was as high as 3.6 ~ 104 colony-forming units （CFU） g-1 dry digestate. The concentrations of heavy metals did not surpass the upper limits established by US Environmental Protection Agency （EPA）. After 28 d, 17% of the organic C （436 g kg-1 dry digestate） and 8% of the organic N （6.92 g kg-1 dry digestate） were mineralized. Emissions of CO2 and CH4 were not significantly affected by fertilization in the wheat-cultivated soil, but digestate significantly increased the cumulative N20 emission by 5 times compared to the urea-amended soil and 63 times compared to the uncultivated unfertilized soil. It could be concluded that digestate was nutrient rich and low in heavy metals and pathogens, and did not affect emissions of CH4 and CO2 when applied to a soil cultivated with wheat, but increased emission of N20. Key Words： biodigester, C and N mineralization potential, faecal coliform, heavy metal, pathogen, pig slurry

关键词： biodigester C and N mineralization potential faecal coliform heavy metal pathogen pig slurry

Pre-fire aboveground biomass, estimated from LiDAR, spectral and field inventory data, as a major driver of burn severity in maritime pine (Pinus pinaster) ecosystems

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Forest Ecosystems 2022年第2期9卷 234-246页

作者： Jose manuel Fernandez-Guisuraga Susana Suarez-Seoane Paulo MFernandes victor Fernandez-Garcia Alfonso Fernandez-Manso Carmen Quintano Leonor Calvo Area of Ecology Department of Biodiversity and Environmental ManagementFaculty of Biological and Environmental SciencesUniversity of Leon24071LeonSpain Centro de Investigacao e de Tecnologias Agroambientais e Biologicas Universidade de Tras-os-Montes e Alto Douro5000-801Vila RealPortugal Department of Organisms and Systems Biology(Ecology Unit)and Research Unit of Biodiversity(IMIB UO-CSIC-PA)University of OviedoOviedoMieresSpain Agrarian Science and Engineering Department School of Agricultural and Forestry EngineeringUniversity of Leon24400PonferradaSpain Electronic Technology Department School of Industrial EngineeringUniversity of Valladolid47011ValladolidSpain Sustainable Forest Management Research Institute University of Valladolid-Spanish National Institute for Agriculture and Food Research and Technology(INIA)34004PalenciaSpain

Background:The characterization of surface and canopy fuel loadings in fire-prone pine ecosystems is critical for understanding fire behavior and anticipating the most harmful ecological effects of ***,the joint consideration of both overstory and understory strata in burn severity assessments is often *** aim of this work was to assess the role of total,overstory and understory pre-fire aboveground biomass(AGB),estimated by means of airborne Light Detection and Ranging(LiDAR)and Landsat data,as drivers of burn severity in a megafire occurred in a pine ecosystem dominated by Pinus pinaster *** the western Mediterranean ***:Total and overstory AGB were more accurately estimated(R^(2) equal to 0.72 and 0.68,respectively)from LiDAR and spectral data than understory AGB(R^(2)=0.26).Density and height percentile LiDAR metrics for several strata were found to be important predictors of *** severity responded markedly and non-linearly to total(R^(2)=0.60)and overstory(R ^(2)=0.53)AGB,whereas the relationship with understory AGB was weaker(R ^(2)=0.21).Nevertheless,the overstory plus understory AGB contribution led to the highest ability to predict burn severity(RMSE=122.46 in dNBR scale),instead of the joint consideration as total AGB(RMSE=158.41).Conclusions:This study novelty evaluated the potential of pre-fire AGB,as a vegetation biophysical property derived from LiDAR,spectral and field plot inventory data,for predicting burn severity,separating the contri-bution of the fuel loads in the understory and overstory strata in Pinus pinaster *** evidenced relationships between burn severity and pre-fire AGB distribution in Pinus pinaster stands would allow the implementation of threshold criteria to support decision making in fuel treatments designed to minimize crown fire hazard.

关键词： Aboveground biomass Burn severity Landsat LiDAR Pinus pinaster

Refractive index measurement of dielectric samples using highly focused radially polarized light(Invited Paper)

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Chinese Optics Letters 2017年第3期15卷 12-15页

作者： Guadalupe López-Morales victor-manuel Rico-Botero Rafael Espinosa-Luna Qiwen Zhan GIPYS Laboratory Centro de Investigaciones en Optica A. C. León Gto 37150 México Department of Electro-Optics and Photonics University of Dayton Dayton OH 45469 USA

In this Letter, a refractive index measurement of a dielectric sample using highly focused radially polarized light is reported. Through imaging analysis of the optical field at the pupil plane of a high numerical aperture （NA） objective lens reflected by the sample under study, the Brewster angle is found. Employing a high NA objective lens allows the measurement of multiple angles of incidence from 0° to 64° in a single shot. The refractive index of the sample is estimated using the measured Brewster angle. The experimental results are compared with the theoretical images computed with the Fresnel theory, and a good agreement is obtained.

关键词： high Refractive index measurement of dielectric samples using highly focused radially polarized light

Experimental Investigations of Various Methods of Sludge Measurements in Storage Oil Tanks

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Advances in Remote Sensing 2015年第2期4卷 119-137页

作者： manuel Monteiro victor Svet Donald Sandilands Sergey Tsysar International Tank Services (Asia Pacific) PTE Ltd. Singapore Singapore

This article describes the results of experimental studies into various methods of measuring sludge volume and its 3D spatial distribution using a base of data received from the inspection of more than 30 storage tanks of different types: external floating roof, internal floating roof and fixed roof. The advantages and disadvantages of making measurements with existing methods are discussed, including the problem of accuracy. Numerous examples of tank survey results are presented.

关键词： Storage Tanks Sludge Volume of Sludge Acoustic Bathymetry Thermography