检索结果-南通市图书馆

Structural Analysis of TiC and TiC-C Core-Shell nanostructures Produced by Pulsed-Laser Ablation

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science and Chemical Engineering 2023年第7期11卷 1-13页

作者： Luis Enrique Iniesta Piña Miguel Ángel Camacho López Rafael Vilchis néstor Víctor Hugo Castrejón Sánchez Delfino Reyes Contreras Mestría en Ciencia de Materiales Facultad de Química Campus Rosedal Universidad Autónoma del Estado de México Toluca México Laboratorio de Fotomedicina Biofotónica y Espectroscopía Láser de Pulsos Ultracortos Facultad de Medicina Universidad Autónoma del Estado de México Toluca México Centro Conjunto de Investigación en Química Sustentable UAEM-UNAM Toluca México TecnM/Tecnológico de Estudios Superiores de Jocotitlán Jocotitlán México Laboratorio de Acústica y nanomateriales Facultad de Ciencias Campus el Cerrillo Universidad Autónoma del Estado de México Toluca México

This paper reports on the ablation process of a pure Ti solid target immersed in a C-enriched acetone solution, leading to the production of titanium carbide (TiC) and Ti-C core-shell nanostructures. The used route of synthesis is generally called pulsed laser ablation in liquid (PLAL). The presence of carbon structures in the solution contributed to the carbon content in the produced Ti-based nanomaterials. The atomic composition of the produced nanostructures was analyzed using SEM-EDS, while TEM micrographs revealed the formation of spherical TiC and core-shell nanostructures ranging from 40 to 100 nm. The identification of atomic planes by HRTEM confirmed a 10 nm diameter C-shell with a graphite structure surrounding the Ti-core. Raman spectroscopy allowed for the identification of D and G peaks for graphite and a Raman signal at 380 and 600 cm−1, assigned to TiC. The results contribute to the state-of-the-art production of TiC and Ti-C core-shell nanostructures using the PLAL route.

关键词： Laser Ablation TiC nanoparticles Core-Shell nanoparticles Pulsed Laser

Identification and Expression of Some Plant Cell Wall-Degrading Enzymes Present in Three Ontogenetics Stages of Thecaphora frezii, a Peanut (<i>Arachis hypogaea</i>L.) Pathogenic Fungus

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

American Journal of Plant Sciences 2022年第1期13卷 1-22页

作者： néstor Walter Soria Ana Cristina Figueroa María Soledad Díaz Valeria Roxana Alasino Pablo Yang Dante Miguel Beltramo Cátedra de Biotecnología Facultad de Ciencias Químicas Unidad Asociada al CONICET: área de Cs. Agrarias Ingeniería Cs. Biológicas Universidad Católica de Córdoba Córdoba Argentina Centro de Excelencia en Productos y Procesos de Córdoba—CEPROCOR Santa María de Punilla Córdoba Argentina COnICET Santa María de Punilla Córdoba Argentina

Peanuts can be affected by the presence of pathogenic microorganisms. The fungus Thecaphora frezii (T. frezii), which belongs to the taxonomic class Ustilaginomycetes, is the causal agent of the disease known as “peanut smut”. The life cycle of this fungus includes three stages, namely teliospores, basidiospores and hyphae. In the hyphae stage, infection occurs in the peanut plant, which requires the involvement of some enzymes secreted by the fungus. These include the Plant Cell Wall-Degrading Enzymes (PCWDEs), which degrade various polysaccharides. This study aimed to identify the presence of transcript for enzymes belonging to the PCWDEs from three stages of T. frezii. For this, total RnA was extracted from the three ontogenetic stages of T. frezii. These samples were analyzed using an RnA-Seq approach and some transcripts were quantified using Real Time PCR. The analysis of the data provided by the RnA-Seq of the three T. frezii stages, it was possible to identify some transcripts that could encode enzymes compatible with polysaccharides degradation that are part of the plant cell wall. In T. frezii transcriptome, 40 deduced proteins would be enzymes with functions of PCWDEs were identified. They were divided into 27 glycoside hydrolases;two polysaccharide lyases;three carbohydrate esterases and eight enzymes with auxiliary activities. In addition, the fungal SnF1 gene was identified whose activity could be affected by high glucose level, and indirectly influence the levels of some PCWDEs. The analysis of the PCWDEs could help to understand part of the fungal infection process and possibly find substances that can control its development.

关键词： Carbohydrate-Degrading Enzymes Phytopathogenic Fungi Smut Fungi Transcriptome Thecaphora frezii

Monitoring hepatitis C virus treatment rates in an Opioid Treatment Program:A longitudinal study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2020年第38期26卷 5874-5883页

作者： Arantza Sanvisens Inmaculada Rivas Eva Faure néstor Espinach Anna Hernandez-Rubio Xavier Majó Joan Colom Robert Muga Department of Internal Medicine Hospital Universitari Germans Trias i PujolBadalona 08916Spain Mental Health and Addiction Service Badalona Serveis Assistencials-BSABadalona 08911Spain Department of Internal Medicine Hospital Universitari Germans Trias i PujolUniversitat Autònoma de BarcelonaBadalona 08916Spain Program on HIV STIs and Viral Hepatitis-PCAVIHV Public Health Agency of CataloniaGeneralitat de CatalunyaBarcelona 08005Spain

BACKGROUnD Direct-acting antivirals(DAAs)are recommended for the treatment of hepatitis C virus(HCV)infection in patients treated with methadone or *** To assess HCV treatment rates in an Opioid Treatment Program(OTP).METHODS This longitudinal study included 501 patients(81.4%men,median age:45 years;interquartile range:39-50 years)enrolled in an OTP between October 2015 and September *** were followed until September *** on sociodemographics,substance use,HCV infection,human immunodeficiency virus(HIV)infection and laboratory parameters were collected at *** analyzed medical records to evaluate HCV ***-Meier methods and Cox regression models were used to analyze the DAA treatment uptake and to identify treatment *** Prevalence of HCV and HIV infection was 70%and 34%,*** anti-HCV-positive(n=336)patients,47.2%,41.3%,and 31.9%used alcohol,cannabis,and cocaine,***-RnA tests were positive in 233(69.3%)*** patients(8.3%)cleared the infection,and 59/308(19.1%)had received interferon-based treatment regimens before *** 249 patients eligible,111(44.6%)received *** rates significantly increased over time from 7.8/100 person-years(p-y)(95%CI:5.0-12.3)in 2015 to 18.9/100 p-y(95%CI:11.7-30.3)in *** a multivariate analysis,patients with HIV co-infection were twice as likely to receive DAAs(HR=1.94,95%CI:1.21-3.12)than patients with HCV *** drug use was an independent risk factor for not receiving treatment against infection(HR=0.48,95%CI:0.29-0.80).COnCLUSIOn HCV treatment is evolving in patients with HCV-HIV *** drug use while in an OTP might negatively impact the readiness to treat infection.

关键词： Direct-acting antiviral agents Opioid Treatment Program Opioid agonist therapy Hepatitis C virus infection Human immunodeficiency virus infection Drug use

Plant cover as an estimator of above-ground biomass in semi-arid woody vegetation in northeast Patagonia,Argentina

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Arid Land 2021年第9期13卷 918-933页

作者： Laura B RODRIGUEZ Silvia S TORRES ROBLES Marcelo F ARTURI Juan M ZEBERIO Andrés C H GRAnD néstor I GASPARRI national University of Río negro Atlantic HeadquartersCenter for Environmental Studies from Norpatagonia(CEANPa)Viedma 8500Argentina national Council of Scientific and Technical Research(COnICET) Viedma 8500Argentina Ecological and Environmental Systems Research Laboratory(LISEA) National University of La PlataLa Plata 1900Argentina national Institute of Agricultural Technology(InTA) AER PatagonesCarmen de Patagones 8504Argentina Institute of Regional Ecology(IER) National University of Tucumán(UNT)-National Council of Scientific and Technical Research(CONICET)Tucumán 4000Argentina Faculty of natural Sciences and Miguel Lillo Institute National University of Tucumán(UNT)Yerba Buena 4107Argentina

The quantification of carbon storage in vegetation biomass is a crucial factor in the estimation and mitigation of CO2 ***,arid and semi-arid regions are considered an important carbon ***,they have received limited attention and,therefore,it should be a priority to develop tools to quantify biomass at the local and regional *** plant variables,such as stem diameter and crown area,were reported to be good predictors of individual plant ***-level variables,such as plant cover and mean height,are also easy-to-measure estimators of above-ground biomass(AGB)in dry *** this study,we estimated the AGB in semi-arid woody vegetation in northeast Patagonia,*** evaluated whether the AGB at the stand level can be estimated based on plant cover and to what extent the estimation accuracy can be improved by the inclusion of other field-measured structure *** also evaluated whether remote sensing technologies can be used to reliably estimate and map the regional mean *** this purpose,we analyzed the relationships between field-measured woody vegetation structure variables and AGB as well as LAnDSAT TM-derived *** obtained a model-based ratio estimate of regional mean AGB and its standard *** plant cover allowed us to obtain a reliable estimation of local AGB,and no better fit was attained by the inclusion of other structure *** stand-level plant cover ranged between 18.7%and 95.2%and AGB between about 2.0 and 70.8 Mg/hm^(2).AGB based on total plant cover was well estimated from LAnDSAT TM bands 2 and 3,which facilitated a model-based ratio estimate of the regional mean AGB(approximately 12.0 Mg/hm^(2))and its sampling error(about 30.0%).The mean AGB of woody vegetation can greatly contribute to carbon storage in semi-arid ***,plant cover estimation by remote sensing images could be used to obtain regional estimates and map biomass,as well as to assess and monitor the i

关键词： above-ground biomass shrublands ratio estimation carbon storage remote sensing Patagonia

南极Gerlache海峡海鸟的取食集群及食性(英文)

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

动物学报 2007年第3期53卷 425-430页

作者： Marco FAVERO néstor Bubén CORIA Universidad nacional de Mar del Plata Facultad Ciencias Exactas y Naturales Departamento de Biología Instituto Antártico Argentino División Biología

1997年12月至1998年2月,我们对南极半岛席尔瓦角善于飞翔海鸟与企鹅的取食关联性进行了研究,同时调查了取食集团中主要鸟种的食性。发现每个取食集团中有35.6-37.0只善于飞翔的海鸟,其中几乎都有纹颊企鹅群(Pygoscelis antarctica),黑背... 详细信息

1997年12月至1998年2月,我们对南极半岛席尔瓦角善于飞翔海鸟与企鹅的取食关联性进行了研究,同时调查了取食集团中主要鸟种的食性。发现每个取食集团中有35.6-37.0只善于飞翔的海鸟,其中几乎都有纹颊企鹅群(Pygoscelis antarctica),黑背鸥(Larus dominicanus)、灰贼鸥(Catharacta maccormicki)、花斑鹱(Daptioncapensis)和巨鹱(Macronectes giganteus)是各集团中最常见的鸟类。各取样单元内有相关性的种数随季节变化而减少,一些种类的减少与特定的物候期有关。南极磷虾(Euphausia superba)是绝大部分飞翔海鸟的主要食物,研究发现黑背鸥与纹颊企鹅所捕食的南极磷虾的大小最为接近。飞翔海鸟的觅食行为表明:在海面上短时停留的飞翔海鸟也能够成功捕捉到磷虾,这可能与磷虾躲避企鹅的捕食有关。

关键词：取食集群促进作用水下捕食者磷虾

Abnormal Succession of Insect Fauna on Pig Carcasses in Tandil (Argentina, Buenos Aires Province)

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Advances in Entomology 2014年第2期2卷 102-113页

作者： A. Verónica Trigo néstor Centeno Laboratorio de Entomología Aplicada y Forense Departamento de Ciencia y Tecnología Universidad Nacional de Quilmes Bernal Argentina

This project was an attempt to reconstruct a death in dubious circumstance which happened in December 2002 in Tandil (Buenos Aires Province). Although the body was in open air, the entomological expertise discovered signs of delayed colonization. In this experiment, pig carcasses used as models to reconstruct the case. One was placed in shadow and another in sunlight (control). The hypothesis was that the climate and the topography affect the necrophagous insect succession in a mountain site. The families of Coleoptera found on the baits were: Silphidae, Dermestidae, Cleridae, Histeridae;of Díptera: Calliphoridae, Sarcophagidae;Asilidae;of Hymenoptera: Formicidae, Encyrtidae and Vespidae.

关键词： Forensic Entomology Calliphoridae Tandil

Knowledge to Ecological Preferences in a Tropical Epiphytic Algae to Use with Eutrophication Indicators

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Protection 2013年第11期4卷 27-35页

作者： Yimmy Montoya-Moreno néstor Aguirre-Ramírez GeoLimna group Engineering Faculty Antioquia University Medellin Colombia.

In Ayapel floodplain periphyton associated to macrophyte roots on the basis of material was collected in fourteen sampling sites in nine moments of compilation. From the analysis of the samples were recorded 550 algal species, of which 56% were diatoms. Furthermore it was valued relative abundances of taxa and the average physicochemical variables to identify the optimal values and tolerance ranges of species. In the case of nitrates optimal value was below 2 mg/L for all algae except for Actinella sp. and Euastrum sinuosum which optimal values were close to zero with low variability. Regarding all species the algal nitrite concentration showed optimum values below 2 mg/L except Encyonema minutum and E. sinuosum whose optimum were 0.4 and 0.5 mg/L respectively. About nitrogen as ammonia was repeated the above situation, i.e. optimum values below 2 mg/L except for E. minutum and E. sinuosum. Respect to phosphorus the species with optimum greater than 0.6 mg/L are the diatoms, in contrast, the lowest values were optimal for E. sinuosum and Actinella sp. From the viewpoint of bioindication high abundance of Synedra goulardii indicates high transparency, Ulnaria ulna and Planothidium lanceolatum indicate lower concentration of dissolved oxygen and water temperature between 29°C - 30°C, Actinella aff. robusta, E. minutum, Cylindrospermopsis raciborski, Lyngbya cf. limnetica, Eunotia naegueli, navicula cryptocephala, Diadesmis confervaceae, Frustulia rhomboides and Aulacoseira granulata.(For more information,please refer to the PDF.)

关键词： Algae Epiphyton Bioindicator Tropical Environment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

新冠肺炎疫情下应对全球治理危机的中国方案

当代世界 2022年第4期 40-44页

作者： [阿根廷]内斯托尔·雷斯蒂沃阿根廷国际关系理事会阿根廷外交部咨询委员会

当今世界高度全球化,国家间和地区间关系紧密交织、日趋复杂,国际秩序正发生深刻变化。新冠肺炎疫情在全球持续蔓延,全球治理体系面临的挑战进一步加剧,亟需进行变革。在此背景下,中国提出的构建人类命运共同体和弘扬全人类共同价值的... 详细信息

当今世界高度全球化,国家间和地区间关系紧密交织、日趋复杂,国际秩序正发生深刻变化。新冠肺炎疫情在全球持续蔓延,全球治理体系面临的挑战进一步加剧,亟需进行变革。在此背景下,中国提出的构建人类命运共同体和弘扬全人类共同价值的理念为改善全球治理提供了一种全新方案。

关键词：全球治理治理危机人类命运共同体肺炎全球化疫情面临的挑战

Use of wild trout for PBDE assessment in freshwater environments: Review and summary of critical factors

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Emerging Contaminants 2015年第1期1卷 54-63页

作者： Juan M.Ríos nerina B.Lana Paula Berton néstor F.Ciocco Jorgelina C.Altamirano Laboratorio de Química Ambiental Instituto Argentino de NivologíaGlaciología y Ciencias Ambientales(IANIGLA)-CONICETMendozaP.O Box 1315500 MendozaArgentina Facultad de Ciencias Exactas y naturales Universidad Nacional de CuyoPadre J.Contreras 13005500 MendozaArgentina Instituto Argentino de Investigaciòn de ZonasÁridas(IADIZA)-COnICET MendozaP.O Box 5075500 MendozaArgentina

Certain wild animals represent sentinels to address issues related to environmental pollution,since they can provide integrative data on both pollutant exposure and biological *** their technological benefits,PBDEs are considered a threat to environmental health due to their persistence,toxicity,and capacity to be *** pollutants have been found geographically widespread in fish,particularly in predator species such as *** aim of this work is to critically review the applicability and usefulness of wild trout for assessing PBDEs in freshwater *** reports include data from highly industrialized areas as well as areas from remote regions with relatively low human activity,including European and north American great lakes and freshwater environments in Europe,Greenland,subarctic areas and Patagonia,respectively.A summary of relevant factors were grouped into organism-specific factors(food habits,age,size,lipid content,sex and reproduction,tissue type,mechanism of contaminant uptake and metabolism),and PBDE levels in the surrounding environment(sediment).Five wild trout species[rainbow trout(Oncorhynchus mykiss),brown trout(Salmo trutta),lake trout(Salvelinus namaycush),arctic char(Salvelinus alpinus),and brook trout(Salvelinus fontinalis)],collected worldwide within the 1994 to present time frame,were *** techniques(principal component analysis-PCA)and mapping approach,showed clear differences in geographic distribution patterns of PBDE levels in trout depending on the region studied:wild trout from European and north American great lakes have the highest PBDE *** pattern could be due to high industrial activity at these locations.A correlational approach used to explore intraspecific relationships between PBDE levels and morphometry,showed positive relationships only for brown ***,brown trout showed the highest trout-to-sediment ratios,which is suggestive of a relatively greater capa

关键词： Critical factors Freshwater environments PBDE Trout Global hotspots