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Textural and geochemical characteristics of late Pleistocene to Holocene fine-grained deep-sea sediment cores(GM6 and GM7),recovered from southwestern Gulf of Mexico

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Journal of Palaeogeography 2018年第3期7卷 253-271页

作者： Abigail Anaya-Gregorio John S.Armstrong-Altrin marfa luisa machain-castillo Patricia C.Montiel-Garcia Mayla A.Ramos-Vazquez Licenciatura en Ingenieria en Geologia Ambiental Area Academica de Ciencias de la Tierra y MaterialesUniversidad Autonoma del Estado de HidalgoMineral de la ReformaHidalgoMexico. Instituto de Ciencias del Mary Limnologia Universidad Nacional Autenoma de MexicoUnidad de Procesos Oceanicos y CosterosCiudad Universitaria04510 Ciudad de MexicoMexico. Area Academica de Ciencias de la Tierra y Materiales Universidad Autonoma del Estado de HidalgoCiudad UniversitariaCarretera Pachuca-Tulancingo Km 4.5Col.CarbonerasC.P.42184 Mineral de la ReformaHidalgoMexico. Posgrado en Ciencias del Mary Limnologia Universidad Nacional Autonoma de MexicoCiudad Universitaria3000CoyoacanC.P.04510 Ciudad de MexicoMexico.

Texture, mineralogy, geochemistry, and 14C ages of two deep-sea sediment cores （GM6 and GM7） recovered in the southwestern Gulf of Mexico were investigated to infer their provenance and depositional condition. The sediments are enriched in fine-grained silt and clay and poor in sand content. Mineralogically, the sediments consist of quartz, calcite, smectite, and kaolinite. Based on the ]4C data, the age of the GM6 and GM7 sediment cores were calculated as 23,615 cal yrs. BP and 19,007 cal yrs. BP, respectively. The weathering indices such as chemical index of alteration （CIA）, chemical index of weathering （CIW）, and plagioclase index of alteration （PIA） in GM6 （56-69, 60-74, and 6]-73, respectively） and GM7 （54-69, 57-76, and 55-74, respectively） cores revealed a moderate-to-high intensity of weathering. The rare earth element （REE） patterns suggested that the sediments were derived mostly by the weathering of intermediate rocks, exposed along the coastal regions of the Gulf of Mexico. The trace elemental ratios like V/Cr （〈2）, Ni/Co （〈2）, and Cu/Zn （〈1）, authigenic uranium content （〈1）, and Ce anomaly （Ce/Ce＊ ≤1） suggested that the sediments were deposited under an oxic condition, which was also revealed by the benthic foraminiferal assemblages throughout the GM6 and GM7 sediment cores.

关键词： Radiocarbon age Manganosite Weathering Palaeoredox condition Provenance Holocene Gulf of Mexico

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Soil Microbial Community-Level Physiological Profiling as Related to Carbon and Nitrogen Availability Under Different Land Uses

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Pedosphere 2016年第2期26卷 216-225页

作者： marfa Celina ZABALOY Jay L. GARLAND Marco ALLEGRINI Elena del Valle GOMEZ Centro de Recursos Naturales Renovables de la Zona Semidrida CONICET Bahia Blanca 8000 Argentina Microbiological and Chemical Exposure Assessment Research Division Environmental Protection Agency Cincinnati OH 45268 USA Facultad de Ciencias Agrarias Universidad Nacional de Rosario Zavalla 2125 Argentina

The goal of this work was to assess soil microbial respiration, determined by the assay of community-level physiological profiling in an oxygen-sensitive microplate （O2-CLPP）, in response to endogenous C and several individual C substrates in the soils with different organic C contents （as a function of soil type and management practice）. We also used the O2-CLPP to determine the respiratory response of these soils to endogenous C and amended C substrates with N addition. A respiratory quotient （RQ） was calculated based on the ratio of the response to endogenous soil C vs. each C-only substrate, and was related to total organic carbon （TOC）. For assessing N availability for microbial activity, the effect of N supplementation on soil respiration, expressed as Nr^tio, was calculated based on the response of several substrates to N addition relative to the response without N. Soils clustered in 4 groups after a principal component analysis （PCA）, based on TOC and their respiratory responses to substrates and endogenous C. These groups reflected differences among soils in their geographic origin, land use and C content. Calculated RQ values were significantly lower in natural forest soils than in managed soils for most C-only substrates. TOC was negatively correlated with RQ （r = -0.65）, indicating that the soils with higher organic matter content increased respiratory efficiency. The N addition in the assay in the absence of C amendment （i. e., only endogenous soil C present） had no effect on microbial respiration in any soil, indicating that these soils were not intrinsically N-limited, but substrate-dependent variation in Nr^tio within soil groups was observed.

关键词： community-level physiological profiling N limitation oxygen biosensor system soil organic C soil respiration

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In-depth analysis of soil management and farmers’perceptions of related risks in two olive grove areas in southern Spain

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International Soil and Water Conservation Research 2021年第3期9卷 461-473页

作者： José A.Gòmez Ana Sanchez Montero Gema Guzman marfa-Auxiliadora Soriano a Institute for Sustainable Agriculture CSICCordobaSpain Agronomy Department University of CordobaCordobaSpain

This manuscript presents a questionnaire-based study aimed to provide a detailed analysis on the different soil management carried out by olive farmers in two representative olive-growing areas in southern Spain(Cordoba and Estepa),their perceptions on cover crop use and the possible influence of the different types of farms and farmers’typologies on these *** results show a relatively large variability of soil management,with fourteen options,as a result of a combination of different alternatives for bare soil and cover crops with the use or not of pruning residues,but with a great similarity between both *** results indicate a high adoption of soil conservation measures in the two study areas,with 63%of farmers using cover crops and 80%a mulch of pruning residues,higher than that reported in previous studies in Southern Spain,and a trend of lower use of these techniques by less experienced and younger *** high penetration of soil conservation measures resulted in a significant reduction of soil erosion risk,as indicated by the relatively low values for the cover and management factor(C)of RUSLE,also calculated and presented in this study,but also the possibility of focusing further efforts on fanners with less *** results indicate the persistence of a minor,but relevant,percentage of farmers using bare soil management(37%)and no mulching(20%),with a moderate concern on the impact of soil erosion on soil degradation and provision of ecosystem *** suggests the need to concentrate efforts also on this cluster of farmers to enhance the success of what seems to be a remarkable expansion of the use of soil conservation measures in recent decades in Southern Spain,but also in similar areas in the Mediterranean basin.

关键词： Tillage Cover crops Olive yield Erosion risk Irrigation Questionnaire

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Can sexual selection and disassortative mating contribute to the maintenance of a shell color polymorphism in an inter- tidal marine snail？

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Current Zoology 2012年第3期58卷 463-474页

作者： Emilio ROLALVAREZ Maria SAURA Angel E DIZ marfa JOSE RIVAS MargaALVAREZ Beatriz CORTES Alicia de COO Daniel ESTEVEZ Laura IGLESIAS Departamento de Bioqufmica Genetica e Inmunologfa Facultad de Biologfa Universidad de Vigo Campus de Vigo 36310 VigoSpain

Littorina fabalis is an intertidal snail commonly living on the brown algae Fucus vesiculosus and showing frequent shell-color polymorphisms in the wild. The evolutionary mechanism underlying this polymorphism is currently unknown. Shell color variation was studied in mated and non-mated specimens of this species from different microareas in one locality from NW Spain, in order to estimate sexual selection and assortative mating that may （still） be operating in this population. The analyses across microareas allowed us to investigate frequency-dependent selection and assortative mating components, mechanisms that could maintain the polymorphism. The presence of shell scars caused by crab attacks, an environmental variable not related with sexual selection or assortative mating, was used as experimental control. This study provides new evidence of significant disas- sortative mating and some degree of sexual selection against some shell colors, supporting the results found 21 years ago in a similar study, i.e. in the same species and locality. The similarity of these estimates during the studied period suggests that this experimental approach is consistent and valid to be extended to other populations and organisms. In addition, sexual selection and assortative mating estimates did not change across microareas differing in shell color frequencies, suggesting than the polymor- phism can not be maintained by a frequency-dependent （sexual selection-based） mechanism. Our main hypothesis is that negative assortative mating could contribute to the maintenance of the polymorphism, perhaps by males showing distinct female color preferences when searching for mates [Current Zoology 58 （3）： 463-474, 2012].

关键词： Fitness estimate Mate choice Mate propensity Negative assortative mating Sexual selection Frequency-dependentselection

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Formulation and Characterization of Film Based on Gum Exudates from Brea Tree （Cercidium praecox）

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Journal of Food Science and Engineering 2013年第3期3卷 113-122页

作者： marfa A. Bertuzzi Anibal M. Slavutsky Instituto de Investigaciones para la Industria Quimica (CONICET) CIUNSa Facultad de lngenieria Universidad Nacional deSalta Salta A4408FVY Argentina Agencia Nacional de Promocion Cientifica y Tecnologica (ANPCyT) Instituto de Investigaciones para la Industria Quimica(CONICET) C1UNSa Universidad Naeional de Salta Salta A4408FVY Argentina

In the present study, films and coatings for food applications based on a gum exudate from Brea tree （Cercidium praecox） were formulated and the influence of plasticizer content on their functional properties was evaluated. Brea gum is a renewable resource available in semi-desert areas, extracted by native people. Films were produced by casting method and characterized through water vapour permeability, mechanical （tensile strength and elongation at break）, morphological and optical properties. Glycerol was used as plasticizer. Brea gum films presented good visual aspect, transparency and amber colour. Microscopic observation showed a dense and homogeneous structure. Film wettability increased with glycerol content due to hydrophilic nature of the plasticizer. Solubility of films in water increased with temperature. Water sorption isotherms of films at 25 ~C showed that at high aw （above 0.50）, the film matrix swells altering its structure and properties. Water vapour permeability remained practically constant up to 20% of glycerol content and then increases linearly with the plasticizer. The addition of glycerol decreased the opacity and tensile strength. The best film properties were obtained at 20% of glycerol concentration.

关键词： Films brea gum mechanical properties barrier properties plasticizer effects

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Hydrogel scaffolds based on blood plasma cryoprecipitate and collagen derived from various sources: Structural, mechanical and biological characteristics

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Bioactive Materials 2019年第1期4卷 334-345页

作者： marfa N.Egorikhina Diana Ya Aleynik Yulia P.Rubtsova Grigory Ya Levin Irina N.Charykova Ludmila L.Semenycheva Marina L.Bugrova Evgeniy A.Zakharychev Federal State Budgetary Educational Institution of Higher Education«Privolzhsky Research Medical University»of the Ministry of Health of the Russian Federation Nizhny NovgorodRussian Federation Lobachevsky State University of Nizhny Novgorod Nizhny NovgorodRussian Federation

At present there is a growing need for tissue engineering products,including the products of *** hydrogel scaffolds have a number of advantages and are increasingly being used to provide means of cell transfer for therapeutic treatments and for inducing tissue *** work presents original hydrogel biopolymer scaffolds based on a blood plasma cryoprecipitate and collagen and formed under conditions of enzymatic *** differently originated collagens were used for the scaffold *** this work the structural and mechanical characteristics of the scaffold were *** was found that,depending on the origin of collagen,scaffolds possess differences in their structural and mechanical *** types of hydrogel scaffolds have good biocompatibility and provide conditions that maintain the three-dimensional growth of adipose tissue stem ***,scaffolds based on such a blood plasma cryoprecipitate and collagen have good prospects as cell carriers and can be widely used in regenerative medicine.

关键词： Biopolymers Blood plasma cryoprecipitate Collagen Hydrogel scaffolds Stem cells

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未来职业早规划

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新东方英语(中学生) 2009年第10期 56-59页

作者： Heather Mayer Jocelyn marfa 李笑

Peer Story同龄故事只要有心,生活中的许多细节和灵感都可以变成职业发展方向。本期即将出场的主人公马克——美国时尚校园杂志《Rez(life)》的主创者,其创刊灵感便来源于他的校园生活。

关键词：青少年时期大学校园教学软件

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Microbiota of Fossil Animals Preserved in Yakut Permafrost

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Journal of Earth Science and Engineering 2014年第8期4卷 484-489页

作者： Neustroev Mikhail Petrovich Tarabukina Nadezhda Petrovna Neustroev Mikhail Mikhailovich Fedorova marfa Pavlovna Stepanova Anna Mikhailovna Parnikova Svetlana Ivanovna Baishev AlekseyAntonovich Laboratory of Veterinary Biotechnology SSI YSRIA (Yakut Scientific Research Institute of Agriculture) Yakutsk 677001 Russia Laboratory of Microbial Preparations Development SSI YSRIA (Yakut Scientific Research Institute of Agricluture) Yakutsk677001 Russia Institute of Natural Sciences NEFU (North-Eastern Federal University) Yakutsk 677001 Russia

Microbiological investigation of the fossil animals preserved in permafrost represents obvious interest for science. Lack of data in this sphere gives even greater importance to any findings giving us opportunity to learn more about remote past of microorganisms. In this respect, preserved remains of fossil are considered as unique biological materials for scientific investigations. Bacillus bacteria strains isolated from the paleomicrobiota of mammoth fauna are not only have high durability （20-30 thousand of years） in permafrost, but are still able to produce biologically active substances. Strains of bacteria of the genus Bacillus, isolated from the tissues of the representatives of the mammoth fauna have strong antagonistic properties to hemolytic streptococci--Streptococcus equi, pathogenic for animals--Salmonella abortus equi, also toxigenic micromycetes genera Aspergillus, Alternuria, Penicillum and fungal pathogens of plant diseases--Botrytis cimeria and Fuzarium oxysporium. The strains of bacteria of the genus Bacillus are not pathogenic to plants and animals, but initially resistant to wide range of antibiotics. Dominance strains of Bacillus bacteria, producing strong bacteriocins in the soft tissues of fossil animals, contributing to their long cryo bio conservation. In addition, bacterial strains of Bacillus subtilis, isolated from paleo microbiota have strong oxidizing properties. Microbiota of fossils preserved in permafrost of Yakutia is of particular interest for microbiology and modem biotechnology.

关键词： Permafrost mammoth fauna microflora Bacillus modem biotechnology.

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西班牙医生准备实行世界上第一例双腿移植术

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英国医学杂志中文版 2010年第5期13卷 270-271页

作者： marfa de Lago 王英民(译) 马德里卫生部北京医院骨科

西班牙国家移植机构已经允许西班牙Valencia的La Fe医院实行世界第一例双腿移植术。Padro Cadavas医生和由35名医务人员组成的小组，将对一名在车祸中失去双腿的年轻患者施行移植手术。

关键词：移植术西班牙世界医生腿医务人员移植手术年轻患者

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西班牙公立大学智力资本测量模型的构建和完善

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国际行政科学评论（中文版） 2017年第3期 168-195页

作者：约兰达·拉米雷斯蒙特塞拉特·曼萨内克阿尔芭·玛利亚·普列戈袁沁茹(译) 穆涵(审校) 孙春晖(审校) 西班牙卡斯蒂亚拉曼查大学会计系不详

在大学中,智力资本方法十分关键,主要由于在这些机构中知识是主要的投入和产出。尽管目前已经进行了测量智力资本的尝试,但仍然有很长的路要走。本文旨在提供一种测量高等教育机构中智力资本的模型。我们在西班牙公立大学中进行了研究,... 详细信息

在大学中,智力资本方法十分关键,主要由于在这些机构中知识是主要的投入和产出。尽管目前已经进行了测量智力资本的尝试,但仍然有很长的路要走。本文旨在提供一种测量高等教育机构中智力资本的模型。我们在西班牙公立大学中进行了研究,根据研究结果来确定需要测量的无形要素,并提出一种新的测量和管理智力资本的框架。对实践工作者的启示本文的主要贡献是验证构成大学智力资本模型的主要无形要素和指标。我们提出的智力资本模型将帮助大学呈现对其利益相关者有用的信息,提升高等教育领域的透明度、问责水平和可比性。本文为大学智力资本实践报告提供了有用和具体的指导。创建智力资本报告框架有益于基准化分析和比较研究,以帮助决策,提升公共政策的协调性,增加整个体系的透明度。

关键词：智力资本模型西班牙大学

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