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Ecological intensification of cropping systems enhances soil functions,mitigates soil erosion,and promotes crop resilience to dry spells in the Brazilian Cerrado

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International Soil and Water Conservation Research 2021年第4期9卷 591-604页

作者： Lucas de Castro Moreira da Silva Junior Cesar Avanzi Devison Souza Peixoto Marina Neves Merlo Emerson Borghi Alvaro Vilela de Resende Salvador Francisco Acuna-guzman Bruno Montoani Silva Department of Soil Science Federal University of Lavras(UFLA)37200-900LavrasMGBrazil Department of Water Resources Federal University of Lavras(UFLA)37200-900LavrasMGBrazil Embrapa Maize and Sorghum Brazilian Agricultural Research Corporation(EMBRAPA)PO Box:28535701-970Sete LagoasMGBrazil Department of Physics Federal University of Lavras(UFLA)37200-900LavrasMGBrazil Center for Engineering and Industrial Development(CIDESI) Pie de la Cuesta 702Desarrollo San PabloQuerétaroQro.76125Mexico

Water scarcity threatens global food security and agricultural systems are challenged to achieve high yields while optimizing water *** deficit can be accentuated by soil physical degradation,which also triggers water losses through runoff and consequently soil *** soil health in cropping systems within the Brazilian Cerrado biome have been surveyed throughout the years,information about soil erosion impacts and its mitigation are still not well understood;especially concerning the role of cropping system diversification and its effects on crop ***,the aim of this study was to assess whether ecological intensification of cropping systems-inclusion of a consorted perennial grass and crop rotation-could promote soil coverage and consequently decrease water erosion and soil,water,and nutrient *** work studied the effects of crop rotation and consorted Brachiaria,along with different levels of investment in fertilization on soil physical quality and on soil,water,and nutrient losses,and crop *** proved that soybean monoculture(SS)is a system of low sustainability even under no-till in the Brazilian Cerrado *** exhibited high susceptibility to soil,water,and nutrient losses,causing low crop *** results showed that water losses in SS cropping system were approximately 10%of the total annual rainfall,and total K losses would require an additional 35%of K ***,ecological intensification of cropping systems resulted in enhanced soil environmental and agronomic functions,increased grain yield,and promoted soil and water conservation:high soil cover rate,and low soil,water and nutrient *** intensification proved to be an adequate practice to boost crop resilience to water deficit in the Brazilian Cerrado.

关键词： Crop rotation Grain production Nutrient losses Soil physical quality Tropical region

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哥伦比亚商店“WOWLA”的商业计划研究

哥伦比亚商店“WOWLA”的商业计划研究

作者： Maria Catalina guzman Lopera 上海外国语大学

学位级别：硕士

本研究的目的是要利用本人在ESIC的工商管理国际硕士课程及SISU中所获得的知识,制定以礼品及装饰品为主打商品的商店的商业计划,并重点研究其可行性。基于对礼物及装饰品店在西班牙并欧洲各地的加速扩展及表现情况,本研究计划在在南美... 详细信息

本研究的目的是要利用本人在ESIC的工商管理国际硕士课程及SISU中所获得的知识,制定以礼品及装饰品为主打商品的商店的商业计划,并重点研究其可行性。基于对礼物及装饰品店在西班牙并欧洲各地的加速扩展及表现情况,本研究计划在在南美哥伦比亚开设一家以Wowla为品牌的公司。公司采用低成本商业模式作业,将成为一家业务快速增长的企业。当前增值礼物或者饰品配件在欧洲迅速普及,在哥伦比亚同样拥有良好商机。公司主要战略是向以实惠的价格哥伦比亚市场引入室内设计产品、个人用品及礼品。Wowla主要集中于哥伦比亚市场,给客人提供设计独特、质优价廉的产品。这些产品专门为家居及个人用途设计,改善室内氛围,带来愉悦感。总体而言,Wowla旨在以具有明确增加值产品为人们带来独特的快乐享受。因为该品牌将在哥伦比亚市场中从零开始,本项目的开展需要充裕的资金和努力。同时,商店的技术和建设工程也将会是Wowla品牌发展及增长的基础。为了评估项目持续盈利的可能性,本研究进行了相关财务预测分析。从分析中可以看出,公司在第一年将会有负净利润,但是可以以种子资本填补;在第五年公司营运将会获得正现金流,而且带来正净现值及良好的内部收益率,意味着此项目是能盈利的。

关键词：商业计划独特设计哥伦比亚市场礼品及布置产品

A Novel Pyrrololactam Alkaloid from the South China Sea Sponge Phacellia Fusca Schmidt

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Chemical Research in Chinese Universities 1991年第3期7卷 178-180页

作者： Florecita De guzman Francis J. Schmitz M. Bilayet Hossain Dick van der Helm Department of Chemistry and Biochemistry Uawersity of Oklahoma Norman USA Department of Chemistry and Biochemistry Uawersity of Oklahoma Norman USADepartment of Chemistry and Biochemistry Uawersity of Oklahoma Norman USADepartment of Chemistry and Biochemistry Uawersity of Oklahoma Norman USA

Pyrrololactam type of alkaloids was found in many marine sponges which belong to the family Axinellidae. In the course of our systematic research for bioactive substances in marine organisms, we studied the sponge Phacellia fusca Schmidt which also belongs to the family Axinelldae. From the chloroform-soluble fraction, ten A-nor-sterols were isolated and identified, while from the water-soluble portion, three known pyrrololactam alkaloids and a new pyrrololactam alkaloid, which was named fuscin, were obtained. The present paper contains the isolation and structure determination of fuscin (1).

关键词： Sponge Fuscin Pyrrololactam Alkaloid

液晶几何相位技术实现光场空间结构全维度调控

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红外与激光工程 2023年第8期52卷 298-300页

作者：李春宇于丙石赵波 Carmelo Rosales-guzman 白振旭朱智涵哈尔滨理工大学黑龙江省量子调控重点实验室大珩协同创新中心黑龙江哈尔滨150080 河北工业大学先进激光技术研究中心天津300401

几何相位平面光学元件由于高效、紧凑及易集成等优点已被广泛用于光场空间结构调控。但以q-plate为代表的此类元件只提供自旋相关的波前控制能力,振幅调控能力的缺失导致无法利用光场的全部空间维度,严重阻碍了相关领域研究的进一步深... 详细信息

几何相位平面光学元件由于高效、紧凑及易集成等优点已被广泛用于光场空间结构调控。但以q-plate为代表的此类元件只提供自旋相关的波前控制能力,振幅调控能力的缺失导致无法利用光场的全部空间维度,严重阻碍了相关领域研究的进一步深化。笔者团队在国家自然科学基金等项目资助下,以液晶人工微结构中的几何相位为物理基础设计并论证一系列新型几何相位元件,解锁了平面光学技术对近轴结构光场的全维度调控能力,为高维经典及量子信息等需要依托光场调控技术的实验研究提供了重要工具。

关键词：几何位相液晶平面光学光场调控

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营养日公司SAS业务计划

营养日公司SAS业务计划

作者： Miguel Angel guzman Aguilar 上海外国语大学

学位级别：硕士

本论文旨在为哥伦比亚加勒比地区巴兰基亚市的一家制造企业提供一项商业计划书,并评估该计划实现的可行性。在第一章中首先回顾了行业情况,以及用于完成计划书其他章节所用的不同方法。接下来,我将呈上一些研究结果和有价值的信息以进... 详细信息

本论文旨在为哥伦比亚加勒比地区巴兰基亚市的一家制造企业提供一项商业计划书,并评估该计划实现的可行性。在第一章中首先回顾了行业情况,以及用于完成计划书其他章节所用的不同方法。接下来,我将呈上一些研究结果和有价值的信息以进一步展开论文。为此我进行了大量的学术研究,从诸如科学出版物,商业年报,书籍杂志等中查证了各种信息,并且在论文展开中应用了这些信息。分析行业呈现的不同机会和实现业务成功的主要因素,是下面几章中要讨论的内容,用以明确潜在客户群,还将分析行业环境,及可能存在的业务壁垒,市场上的竞争对手和现有产品等。凭此制定市场渗透战略,以确保客户购买我们的产品而非其他竞争对手的产品。论文的最后一部分列出了项目执行所需费用,以及从成品销售中将要获得的收入。达到3.232.618哥伦比亚比索的销售额后是盈亏平衡点,自此开始盈利,而这一切将在第二年实现。生产过程的优化和原材料的选择(替代品和补充产品)有助于企业根据初始投资和每个时期的利润实现充足盈利。

关键词：中小企业供应链营销

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基于特征权重计算方法的情感分析

基于特征权重计算方法的情感分析

作者： ANA MADELEYN OPORTO guzman 华南理工大学

学位级别：硕士

近年来,情感分析一直是自然语言处理研究者群体日益关注的主题。情感分析可以帮助公司和公共管理部门的人员更多地了解客户的意见,并帮助他们做出一些决定。在本文中,我们首先介绍了情感分析任务的背景,定义,以便读者更好地理解本文的... 详细信息

近年来,情感分析一直是自然语言处理研究者群体日益关注的主题。情感分析可以帮助公司和公共管理部门的人员更多地了解客户的意见,并帮助他们做出一些决定。在本文中,我们首先介绍了情感分析任务的背景,定义,以便读者更好地理解本文的研究目标以及论文的贡献。我们还介绍了最近的几种情感分析的方法,如概率算法(朴素贝叶斯),最近邻算法和变量算法,决策树或分类和矢量支持机器。然后介绍了构建情感分析系统的步骤,包括预处理,特征提取和性能评估。最后,我们更加关注由在线酒店评论组成的数据集,并应用监督机器学习方法Na?ve Bayes使用unigram特征和两种类型的信息(频率和TF-IDF)来实现文档的极性分类。如我们的实验结果所示,在准确性,精确度,召回率和Fcore方面,我们的模型优于其他模型。

关键词：情感分析机器学习朴素贝叶斯

Species diversity of thrips (Thysanoptera) in selected avocado orchards from Mexico based on morphology and molecular data

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Journal of Integrative Agriculture 2018年第11期17卷 2509-2517页

作者： Daniel Bravo-Perez Ma. Teresa Santillbn-Galicia Roberto M. Johansen-Naime Hector Gonzalez-Hernandez Obdulia L. Segura-Leon Daniel L, Ochoa-Martinez Stephanie guzman-Valencia Posgrado en Fitosanidad-Entomologia y Acarologia Colegio de Postgraduados Km 36.5 Carretera Mexico-Texcoco Montecillo Texcoco Estado de Mexico 56230 Mexico Instituto de Biologia de la Universidad Nacional Autonoma de Mexico (IBUNAM) Circuito exterior s/n Ciudad Universitaria Coyoacan Ciudad de Mexico 04510 Mexico Posgrado en Fitosanidad-Fitopatologia Colegio de Postgraduados Km 36.5 Carretera Mexico-Texcoco Montecillo Texcoco Estado de Mexico 56230 Mexico

Avocado is one of the most important crops in the world, and Mexico is the largest producer of this fruit. Several insect pests affect its production, and thrips are amongst the most important. A key step in the design of control methods is accurate species identification. Despite this, formal reports on species diversity of thrips in Mexico are very scarce. Morphological identification can sometimes be time-consuming and inconclusive. Therefore, we explored the species diversity of thrips in Mexican avocado orchards （Michoacan state） based on partial sequences of the mitochondrial gene cytochrome oxidase subunit I （COl）. Forty-four specimens were analysed, which represented approximately 8% of all individuals collected from five localities distributed in three Municipalities. All specimens were analysed using the COl marker, and specimens within the genera Frankliniella were also analysed using a marker within the D2 domain of the 28S （28SD2） nuclear ribosomal DNA. Molecular identifications were confirmed using morphological taxonomy. Overall, six genera were found （Neohydatothrips, Scirtothrips, Frankliniella, Arorathrips, Caliothrips and Leptothrips）. AII genera contained only one species, except Frankliniella, for which there were six species. Data from the two molecular markers suggest the existence of cryptic species within Mexican F. occidentalis populations.

关键词： molecular taxonomy morphological identification cytochrome oxidase subunit I 28S nuclear ribosomal DNA.

Arginine Metabolism in Cancer:A Valid Therapeutic Target?

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Journal of Nutritional Oncology 2017年第1期2卷 7-15页

作者： Vance L. Albaugh Carolina Pinzon-guzman Adrian Barbul Division of General Surgery Department of Surgery Vanderbilt University School of Medicine Nashville TN 37232 USA

Arginine is a conditionally essential amino acid that has been identified as an important player in a number of biologic processes,including normal functions of the cardiovascular and immune *** studies have demonstrated that arginine is necessary for cellular growth and can become limiting in states of rapid growth like *** this requirement for arginine in malignant cells,investigators have examined the potential for arginine deprivation therapy as an adjuvant treatment for cancers that are unable to synthesize arginine de ***,arginine has been identified as being critically important for immune surveillance that targets and destroys malignant ***,paradoxically,arginine has been identified as being both necessary for cancer growth and normal immune destruction of malignant cells.A number of factors,including the type of cancer,expression of arginine synthetic genes,tumor microenvironment and host immune cell-cancer cell interactions,can affect the progression of *** we review the data supporting arginine deprivation and supplementation in cancer therapies and the currently registered trials that aim at understanding which of these strategies may lead to advances in cancer therapy.

关键词： Tumors Arginine metabolism Anti-cancer activity

LDAP Injection Techniques

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Wireless Sensor Network 2009年第4期1卷 233-244页

作者： Jose Maria ALONSO Antonio guzman Marta BELTRAN Rodolfo BORDON 不详

The increase in the number of databases accessed only by some applications has made code injection attacks an important threat to almost any current system. If one of these applications accepts inputs from a client and executes these inputs without first validating them, the attackers are free to execute their own queries and therefore, to extract, modify or delete the content of the database associated to the application. In this paper a deep analysis of the LDAP injection techniques is presented. Furthermore, a clear distinction between classic and blind injection techniques is made.

关键词： Web Applications Security Code Injection Techniques LDAP