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Effects of Tillage and Crop Residue Management on Maize Yields and Net Returns in the Central Mexican Highlands Under Drought Conditions

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Pedosphere 2014年第4期24卷 476-486页

作者： R.ROMERO-PEREZGROVAS N.VERHULST D.de la ROSA V.HERNáNdeZ M.MAERTENS J.deCKERS B.GOVAERTS International Maize and Wheat Improvement Center(CIMMYT) P.O.Box 6-641Mexico D.F.06600(Mexico) department of Earth and Environmental Sciences University of LeuvenCelestijnenlaan 200 ELeuven 3001(Belgium) Mathematics Research Center(CIMAT) Jalisco S/NValencianaGuanajuatoMexico CP 36240(Mexico)

In the subtropical highlands of Central Mexico, where the main crop is maize （Zea mays）, the conventional practice （CP） involves tillage, monoculture and residue removal, leading to soil degradation and unsustainable use of natural resources and agricultural inputs. Conservation agriculture （CA） has been proposed as a viable alternative in the region, based on reduction in tillage, retention of adequate levels of crop residues and soil surface cover and use of crop rotation. This study began in 2009 when the highlands of Central Mexico suffered from a prolonged drought during vegetative maize growth in July-August, providing an opportunity for the on-farm comparison of CA with CP under severe drought conditions which 21 climate change models projected to become more frequent. Under dry conditions, CA resulted in higher yields and net returns per hectare as early as the first and second years after adoption by farmers. As an average of 27 plots under farmers＇ management in 2009, the maize yields were 26% higher under CA （6.3 t ha-1） than under CP （5.0 t ha-l）. 2010 was close to a normal year in terms of rainfall so yields were higher than in 2009 for both practices; in addition, the yield difference between the practices was reduced to 19% （6.8 t ha-1 for CA vs. 5.7 t ha-1 for CP）. When all the 2009 and 2010 observations were analyzed in a modified stability analysis, CA had an overall positive effect of 3 838 Mexican Pesos ha-1 （320 $US ha-1） on net return and 1.3 t ha-1 on yield. After only one to two years of adoption by farmers on their fields, CA had higher yields and net returns under dry conditions that were even drier than those predicted by the analyzed 21 climate change models under a climate change scenario, emission scenario A2.

关键词： climate change conservation agriculture conventional practice emission scenario modified stability analysis

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Cosmology of the Nambu-Jona-lasinio Model

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Journal of Modern Physics 2016年第13期7卷 1777-1800页

作者： Leonardo Quintanar G. A. de la Macorra Instituto de fisica Universidad Nacional Autonoma de Mexico A.P. 20-364 01000 Mexico D.F. Mexico

We review the Nambu and Jona-lasinio model (NJL), proposed long time ago, in the sixties, as a fermion interaction theory with chiral symmetry. The theory is not renormalizable and presents a symmetry breaking due to quantum effects which depends on the strength of the coupling constant. We may associate a phase transition with this symmetry breaking, leading from fermion states to a fermion condensate which can be described effectively by a scalar field. Our purpose in this paper is to exploit the interesting properties of NJL in a different context other than particle physics by studying its cosmological dynamics. We are interested in finding whether possibly the NJL model could be used to describe the still unknown dark energy and/or dark matter, from up to 95% of the energy content of the universe at present time.

关键词： Cosmology Nambu Jona lasinio

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Reversal of age-associated frailty by controlled physical exercise:The pre-clinical and clinical evidences

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Sports Medicine and Health Science 2019年第1期1卷 33-39页

作者： C.Arc-Chagnaud f.Millan A.Salvador-Pascual A.G.Correas G.Olaso-Gonzalez A.de la Rosa A.Carretero M.C.Gomez-Cabrera J.Viña freshage Research Group Department of PhysiologyFaculty of MedicineUniversity of Valencia and CIBERFESFundacion Investigacion Hospital Clínico Universitario/INCLIVAValenciaSpain INRA UMR866 Dynamique Musculaire et MetabolismeUniversite de MontpellierF-34060MontpellierFrance

demographic aging is one of the most serious challenges facing our *** we live longer,we do not live better because it is considered that approximately 16–20%of our life is spent in late-life *** people have the greatest risk of developing frailty increasing the risk of presenting various adverse health events such as low quality of life,disability,hospitalization and even *** men and women over 65 years old have lower muscle quality and muscle mass and higher percentage of body fat than non-frail people of the same *** this review we will address the main physiological changes in the muscular and nervous system associated to *** specifically we will review the changes in muscle mass,quality,and strength relating them with the decrease in capillarization and muscular oxidative capacity as well as with the alterations in protein synthesis in the muscle with *** last section of the manuscript will be devoted to the animal models of frailty and the indexes developed to measure frailty in these *** will finally address the importance of exercise training as an intervention to delay or even reverse frailty.

关键词： Sarcopenia Multicomponent exercise Disability Skeletal muscle Healthy aging

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自主机器人使能技术在制造业中的应用（英文）

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Transactions of Nanjing University of Aeronautics and Astronautics 2024年第4期 403-431页

作者： ERD?S Gábor ABAI Kristóf BEREGI Richárd CSEMPESZ János CSERTEG Tamás GODó Gábor HAJóS Mátyás HáY Borbála HORVáTH Dániel HORVáTH Gergely JUNIKI ádám KEMéNY Zsolt KOVáCS András NACSA János PANITI Imre PEDONE Gianfranco TAKáCS Emma TIPARY Bence ZAHORáN László VáNCZA József 匈牙利研究网络计算机科学与控制研究所布达佩斯经济与技术大学制造科学与技术系 EPIC非盈利创新实验室厄特沃什·罗兰大学

自主制造系统的研究既受益于信息物理融合系统这一新技术的推动，也响应工业实际需求的号召。目前，先进的传感器技术、数字孪生、人工智能和新型通信技术可以支持半结构化工业环境中的自主操作，可实现对生产过程的实时监控、情况识别... 详细信息

自主制造系统的研究既受益于信息物理融合系统这一新技术的推动，也响应工业实际需求的号召。目前，先进的传感器技术、数字孪生、人工智能和新型通信技术可以支持半结构化工业环境中的自主操作，可实现对生产过程的实时监控、情况识别和预测、自动和自适应（重新）规划、团队合作，以及通过学习提高性能。本文总结了实现自主工业机器人技术的主要需求，提出了实现此类系统的通用工作流程，并介绍了HUN-REN SZTAKI最近在装配、焊接、打磨、拾取和放置以及机械加工等多个应用领域的广泛实践。这些解决方案的共同点是以通用的数字孪生概念为核心。最后，本文提出实现工业自主机器人解决方案的一般建议，并讨论了未来要研究的一些开放性问题。

关键词：工业机器人自动化数字孪生使能技术

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SURfACE STUDIES IN ULTRATHIN BINARY IRON OXIde fILMS:ANCIENT MATERIALS,NEW OPPORTUNITIES

SURFACE STUDIES IN ULTRATHIN BINARY IRON OXIDE FILMS:ANCIENT...

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8th International Symposium on the Industrial Applications of the Mossbauer Effect

作者： M.Monti J.de la figuera J.f.Marco Instituto de Quimica fisica "Rocasolano" CSIC.Serrano 11928006 Madrid.Spain.

Binary iron oxides(feO,feO,Y-feO,a-feO) are well-known *** the Mossbauer spectroscopic point of view they have been extensively studied and an overwhelming amount of information is available in the literature both for the bulk materials as for other forms of these materials(for example, nanoparticles).The properties of these oxides in ultrathin

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Comparison of Pharmacokinetic Variability of Metformin in German Caucasian and Chinese subjects

Comparison of Pharmacokinetic Variability of Metformin in Ge...

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第十五届国际药理学大会

作者： Harrison f Yin O Schnelle K de la Mote S Chow M Harrison Clinical Research GmbH MunichGermany. School of Pharmacy Faculty of MedicineChinese University of Hong Kong. Harrison Clinical Research GmbH MunichGermany. Harrison Clinical Research GmbH MunichGermany. School of Pharmacy Faculty of MedicineChinese University of Hong Kong.

＜正＞ Purpose: To evaluate the inter - and intra - individual variability of kinetics of metfomin. a representative substrate of organic cation transporter （OCT2） in Germans and Chinese. Methods: Metformin kinetic data following 2 bioequivalent formulations in healthy Germans （n = 24） or Chinese （n = 28） were evaluated. The inter- and intra - subject variances were estimated based on ANOVA. The genetic contribution （rGC） was calculated using a standard formula from these variances. Results: The mean metformin oral clearance （CL/f） was 1.35 and 1. 05 L/h/kg （p＜0.0l）（with inter- individual CV of 32.1 and 32.2% ） in Germans and Chinese respectively. Their mean drug elimination half - life （T1/2） was 3.89 and 3.78 h and the respective rGC 0.76 and 0.72 （p＞0.05）. Conclusion: The total exposure of metformin appeared to be greater and its elimination t1/2 and variability were similar in German Caucasian and Chinese subjects. Data mining from the bioequivalence studies in different ethnic groups may provide a rapid approach for identifying potential differences of commonly used drugs in different ethnic populations.

关键词： pharmacogenetics metformin transporters

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Low-Cost and Biodegradable Thermoelectric devices Based on van der Waals Semiconductors on Paper Substrates

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Energy & Environmental Materials 2024年第1期7卷 201-206页

作者： Gulsum Ersu Carmen Munuera federico J.Mompean Daniel Vaquero Jorge Quereda João Elias f.S.Rodrigues Jose A.Alonso Eduardo flores Jose R.Ares Isabel J.ferrer Abdullah M.Al-Enizi Ayman Nafady Sruthi Kuriakose Joshua O.Island Andres Castellanos-Gomez Materials Science factory Instituto de Ciencia de Materiales de Madrid(ICMM-CSIC)Madrid E-28049Spain Nanotechnology Group USAL-NanolabUnivesidad de SalamancaSalamanca Junta de Castilla y León 37007Spain GISC Departamento de Física de MaterialesUniversidad Complutense de MadridMadrid E-28040Spain departamento de física Aplicada Centro de Investigación y Estudios AvanzadosMérida 97310Mexico MIRE Group Departamento de Física de MaterialesUniversidad Autónoma de MadridMadrid E-28049Spain Instituto Nicolás Cabrera Universidad Autónoma de MadridMadrid E-28049Spain department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia department of Physics and Astronomy University of Nevada Las VegasLas Vegas NV 89154USA

We present a method to fabricate handcrafted thermoelectric devices on standard office paper *** devices are based on thin films of WS_(2),Te,and BP(P-type semiconductors)and TiS_(3)and TiS_(2)(N-type semiconductors),deposited by simply rubbing powder of these materials against *** thermoelectric properties of these semiconducting films revealed maximum Seebeck coefficients of(+1.32±0.27)mV K^(-1)and(-0.82±0.15)mV K^(-1)for WS_(2)and TiS_(3),***,Peltier elements were fabricated by interconnecting the P-and N-type films with graphite electrodes.A thermopower value up to 6.11 mV K^(-1)was obtained when the Peltier element were constructed with three *** findings of this work show proof-of-concept devices to illustrate the potential application of semiconducting van der Waals materials in future thermoelectric power generation as well as temperature sensing for low-cost disposable electronic devices.

关键词： paper-based electronics Seebeck effect semiconductors thermoelectrics van der Waals materials

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Physiological and pathological role of local and immigrating colonic stem cells

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World Journal of Gastroenterology 2012年第4期18卷 295-301页

作者： ferenc Sipos Gábor Valcz Béla Molnár 2nd department of Internal Medicine Semmelweis University Molecular Medicine Research Unit Hungarian Academy of Sciences

The latest avenue of research is revealing the existence of and role for the colonic stem cells in the physiological renewal of the mucosa and in pathological circumstanc- es where they have both positive and negative effects. In the case of human colon, different levels of stem cell compartments exist. first, the crypt epithelial stem cells, which have a role in the normal crypt epithelial cell dynamics and in colorectal carcinogenesis. Close to the crypts, the second layer of stern cells can be found; the local subepithelial stem cell niche, including the pericryptic subepithelial myofibroblasts that regulate the epithelial cell differentiation and have a crucial role in cancer progression and chronic inflammation-related fibrosis. The third level of stem cell compartment is the immigrating bone-marrow-derived stem cells, which have an important role in wound healing after severe mucosal inflammation, but are also involved in cancer invasion. This paper focuses on stem cell biology in the context of physiological and pathological processes in the human colon.

关键词： Colon Mesencyhmal stem cells Bone marrow Myofibroblast fibrosis Colorectal cancer Para-thyroid hormone Transforming growth factor-β

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施用生物炭和有机肥对新垦红壤氮素气态排放的影响

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土壤通报 2024年第5期55卷 1366-1375页

作者：胡林松达布希拉图杨宇李成蓉黄江凌云南农业大学资源与环境学院云南昆明650201 玉溪市三湖生态环境保护研究与工程管理中心云南玉溪653100

【目的】探究新垦梯地山原红壤施用生物炭和有机肥对N_(2)O排放和NH_(3)挥发变化的影响。【方法】通过定位小区两茬白菜种植试验,以常规施用化肥(CK)为对照,在CK的基础上施用7500 kg hm^(−2)生物炭(B)和施用7100 kg hm^(−2)有机肥(f),... 详细信息

【目的】探究新垦梯地山原红壤施用生物炭和有机肥对N_(2)O排放和NH_(3)挥发变化的影响。【方法】通过定位小区两茬白菜种植试验,以常规施用化肥(CK)为对照,在CK的基础上施用7500 kg hm^(−2)生物炭(B)和施用7100 kg hm^(−2)有机肥(f),共设置3个处理,每个处理3次重复,共9个试验小区,随机区组设计,测定各处理土壤N_(2)O排放和NH_(3)挥发量变化和土壤阳离子交换量、含氧官能团、总有机碳、水溶性有机碳、微生物量碳含量和团聚体的稳定性等指标,通过分析氮素气态排放损失与土壤性质间关系,揭示施用生物炭、有机肥与氮素气体挥发变化的机理。【结果】施用生物炭和有机肥均显著降低土壤N_(2)O累积排放量和NH_(3)累积挥发量,两者对土壤N_(2)O的减排效果无显著差异,施用有机肥对NH_(3)挥发的减排效果显著优于生物炭(P0.25 mm粒径的团聚体百分比和水溶性有机碳是影响土壤N_(2)O排放和NH_(3)挥发的主要因子。【结论】施用有机肥能够提高土壤微生物量碳、水溶性有机碳含量,有利于土壤大团聚体的形成及其稳定性的增强,进而抑制土壤氮素气体挥发;施用有机肥与生物炭两者相比,前者抑制土壤氮素挥发的效果优于后者。

关键词：生物炭有机肥 N_(2)O排放 NH_(3)挥发土壤理化性质

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黄绿色羟基磷铝锂石的谱学特征及其颜色成因

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光谱学与光谱分析 2024年第3期44卷 777-783页

作者：张娟李可心秦冬梅包德清王朝文武汉工程科技学院艺术与传媒学院湖北武汉430200 中国地质大学(武汉)珠宝学院湖北武汉430074

磷铝锂石为含f和OH的连续固溶体矿物,属于一种稀有宝石品种,然而国内对其鲜有研究报道,尤其对快速无损估计f含量从而确定宝石名称以及宝石颜色成因研究较少。对市场上收集的黄绿色宝石级磷铝锂石分别进行常规宝石学、激光剥蚀电感耦合... 详细信息

磷铝锂石为含f和OH的连续固溶体矿物,属于一种稀有宝石品种,然而国内对其鲜有研究报道,尤其对快速无损估计f含量从而确定宝石名称以及宝石颜色成因研究较少。对市场上收集的黄绿色宝石级磷铝锂石分别进行常规宝石学、激光剥蚀电感耦合等离子体质谱仪(la-ICP-MS)、红外光谱(fTIR)、拉曼光谱(Raman)、紫外-可见吸收光谱(UV-Vis)测试与分析。常规宝石学测试结果显示较高的折射率和较低的相对密度的特征均指示研究样品属于羟磷铝锂石端元。研究样品在400~1500 cm^(-1)的红外光谱指纹区表现为430 cm^(-1)的吸收谱带,归属Li—O键的弯曲振动;494、546、604和664 cm^(-1)的吸收为PO43-的弯曲振动和AlO6键的伸缩振动共同作用所致;~832 cm^(-1)为OH的弯曲振动(δOH);~1032、~1090、~1211 cm^(-1)为PO43-的伸缩振动。~3386 cm^(-1)左右,是OH的伸缩振动(νOH)。拉曼光谱显示样品具有305、430、489、648、806、893、1013、1058、1107、1193和3367 cm^(-1)等典型拉曼峰。在3367 cm^(-1)左右的相对较宽的峰是典型的OH伸缩振动,1000~1200 cm^(-1)之间的一组峰是PO43-的非对称伸缩振动(V3)。在600 cm^(-1)以下的拉曼光谱峰,为PO43-的非对称伸缩振动和Al—O键的伸缩振动所致。通过利用折射率高值指数、红外和拉曼光谱指数对磷铝锂石f含量进行了综合估算,折射率高值指数nγ、拉曼光谱中3367 cm^(-1)左右的峰值和1058 cm^(-1)左右的峰值之差以及3367 cm^(-1)附近拉曼峰的半高宽(fWHM)指数是氟磷铝锂石-羟磷铝锂石系列中f含量的良好指标,可被用于快速和间接地半定量估计磷铝锂石刻面宝石的f含量。激光剥蚀电感耦合等离子体质谱la-ICP-MS结果显示,研究样品的主要元素组成为P2O5、Al_(2)O_(3)和Li_(2)O外,还含有微量的fe,与羟磷铝锂石的化学成分相符。fe在磷铝锂石中以类质同象取代Al,O^(2-)—fe^(3+)之间电价转移,fe^(3+)—fe^(2+)价键间电荷转移和fe^(3+)的d—d轨道的自旋禁阻跃迁同时对蓝紫区和橙红区的吸收,与紫外-可见光谱测试结果反映出蓝紫区(300~420 nm)和黄橙区(590 nm附近)的吸收较为一致,可能是导致羟磷铝锂石呈黄绿色调的主要原因。

关键词：羟基磷铝锂石 la-ICP-MS 紫外-可见吸收光谱拉曼光谱颜色成因

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