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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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2008年的全球沙尘暴:观测与HYSPLIT模式验证

2008年的全球沙尘暴:观测与HYSPLIT模式验证

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第28届中国气象学会年会

作者：王亚强 Ariel F.Stein Roland R.draxler Jesús d.de la rosa 张小曳中国气象科学研究院 Associate Unit CSIC-University of Huelva "Atmospheric Pollution"University of HuelvaCampus El CarmenHuelvaSpain Earth Resources&Technology Inc.on assignment to NOAA Air Resources LaboratorySilver SpringMarylandUSA NOAA Air Resources laboratory Silver SpringMarylandUSA

分别采用了两种沙尘释放模型,利用HYSPLIT模式对2008年全球沙尘分布进行了数值模拟。第一个沙尘释放模型假定沙尘可以从任何模式定义为沙漠的土地利用格点释放出来,第二个模型利用了基于卫星观测获得的经验算法。为了研究2008年全球沙... 详细信息

分别采用了两种沙尘释放模型,利用HYSPLIT模式对2008年全球沙尘分布进行了数值模拟。第一个沙尘释放模型假定沙尘可以从任何模式定义为沙漠的土地利用格点释放出来,第二个模型利用了基于卫星观测获得的经验算法。为了研究2008年全球沙尘暴特性,并对模式结果进行验证,使用卫星反演的气溶胶指数数据和全球综合地面小时观测（ISH）数据分析了沙尘暴的空间分布和季节变化。还利用中国北方的四个站点和西班牙两个站点的PM10观测数据以及撒哈拉沙漠中部的一个站点的气溶胶光学厚度（AOd）观测数据对模式结果进行了验证。观测数据显示出了高沙尘暴发生频率的"沙尘带",包括北非、中东、蒙古国和中国西北部地区,也有一些沙尘暴发生在澳大利亚、墨西哥、阿根廷和南美洲其它地区。东亚的沙尘暴主要发生在春季,而其它地区显示出了不同的季节分布。总体来说,两种沙尘释放模型的模式结果都再现了多数地区的沙尘暴发生频率。第一个沙尘释放模式高估了东亚下风区的沙尘浓度,低估了北非和中东地区的沙尘浓度。第二个沙尘释放模型对北非和中东地区的模拟有所改进,但低估了东亚地区的沙尘浓度。

关键词：沙尘暴观测 HYSPLIT模式验证

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Fatty acids in microalgae and cyanobacteria in a changing world:Contrasting temperate and cold environments

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BIOCELL 2022年第3期46卷 607-621页

作者： MARCELO P.HERNANdO IRENE R.SCHLOSS FLORENCIA de la rosa MARLEEN de TROCH Comisión Nacional de Energía Atómica(CNEA) Centro Atómico ConstituyentesDepartamento de RadiobiologíaSan MartínBuenos AiresArgentina Red.de Investigación de Estresores Marinos-costeros en América latina y el Caribe(REMARCO) Mar del Plata7602Argentina Instituto Antártico Argentino(IAA) San MartínBuenos AiresArgentina Centro Austral de Investigaciones Científicas(CAdIC-CONICET) Ushuaia9410Argentina Universidad Nacional de Tierra del Fuego Ushuaia9410Argentina Instituto de Ciencias Básicas y Experimentales(ICBE) Universidad de MorónMorónBuenos AiresArgentina Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Buenos AiresArgentina Ghent University Faculty of SciencesBiology DepartmentMarine BiologyGhent9000Belgium

Under the present changing climate conditions and the observed temperature increase,it is of high importance to understand its effects on aquatic microbial life,and organisms’adaptations at the biochemical *** adjust to temperature or salinity stress and avoid cell damage,organisms alter their degree of fatty acids(FAs)***,temperature is expected to have strong effects on both the quantity and quality of FAs in aquatic *** we review some recent findings about FAs sensitivity to climate change in contrasting ***,heat waves may induce changes in the relative abundance of polyunsaturated FAs(PUFA).However,the impact of the exposure to warming waters is different in temperate and polar *** cold marine waters,high concentration of omega-3(ω3)FAs such as eicosapentaenoic acid(EPA)is promoted due to the activation of the desaturase *** this way,cells have enough energy to produce or activate antioxidant protection mechanisms and avoid oxidative stress due to heat ***,under high irradiance and heat wave conditions in temperate environments,photosystems’protection is achieved by decreasing EPA concentration due to desaturase *** FAs are transferred in aquatic food ***,any alteration in the production of essential FAs by phytoplankton(the main source ofω3)due to climate warming can be transferred to higher trophic levels,with cascading effects for the entire aquatic ecosystem.

关键词： Antarctic Temperate Essential FAs Increased temperature Microalgae Cyanobacteria

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Vascular endothelial growth factor：an essential neurotrophic factor for motoneurons？

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Neural Regeneration Research 2018年第7期13卷 1181-1182页

作者： Paula M.Calvo Angel M.Pastor rosa R.de la Cruz departamento de Fisiologia Facultad de Biologia Universidad de Sevilla Sevilla Spain

Vascular endothelial growth factor（VEGF）,an angiogenic factor with neuroprotective effects：The VEGF was initially characterized by its vasculogenic and angiogenic activities and its capacity to promote vascular permeability（Yancopoulos et al.,2000）.VEGF is also known as VEGF-A and is the prototype member of a related group of five trophic factors,VEGF-B,VEGF-C,VEGF-d and placental growth factor（Pl GF;lange et al.,2016）.

关键词： VEGFR Vascular endothelial growth factor:an essential neurotrophic factor for motoneurons

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Role of vascular endothelial growth factor as a critical neurotrophic factor for the survival and physiology of motoneurons

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Neural Regeneration Research 2023年第8期18卷 1691-1696页

作者： Paula M.Calvo Rosendo G.Hernández rosa R.de la Cruz Angel M.Pastor departamento de Fisiología Facultad de BiologíaUniversidad de SevillaSevillaSpain

Vascular endothelial growth factor(VEGF)was discovered by its angiogenic ***,during evolution,it appeared earlier as a neurotrophic factor required for the development of the nervous system in invertebrates lacking a circulatory *** aimed at reviewing recent evidence indicating that VEGF has neuroprotective effects in neurons exposed to a variety of *** particular interest is the link established between VEGF and motoneurons,especially after the design of the VEGFδ/δmutant *** mice are characterized by low levels of VEGF and.develop muscle weakness and motoneuron degeneration resembling amyotrophic lateral *** administration of VEGF through several routes to animal models of amyotrophic lateral sclerosis delays motor impairment and motoneuron degeneration and increases life *** are new recent advances in the role of VEGF in the physiology of *** experimental aims use the extraocular(abducens)motoneurons lesioned by axotomy as a model for studying VEGF *** abducens motoneurons exhibit severe alterations in their discharge activity and a loss of synaptic *** exogenous administration of VEGF to axotomized abducens motoneurons,either from the transected nerve or intraventricularly,fully restores the synaptic and discharge properties of abducens motoneurons,despite being *** addition,when an anti-VEGF neutralizing antibody is delivered from the muscle to intact,uninjured abducens motoneurons,these cells display alterations in their discharge pattern and a loss of synaptic boutons that resemble the state of *** these data indicate that VEGF is an essential neurotrophic factor for motoneurons.

关键词： abducens nucleus amyotrophic lateral sclerosis cell death extracellular single-unit recordings eye movements neurodegeneration oculomotor trophic factors

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do large brains of long-living mammals prefer non-newly generated,immature neurons？

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Neural Regeneration Research 2018年第4期13卷 633-634页

作者： Ottavia Palazzo Chiara la rosa Matteo Piumatti Luca Bonfanti Neuroscience Institute Cavalieri Ottolenghi(NICO) OrbassanoItaly institute of zoology-neurogenetics universitat regensburgGermany department of veterinary sciences university of turinGrugliasco(TO)Italy universitélibre de bruxelles(ulb) institute for interdisciplinary research in human biology(iribhm)BrusselsBelgium

Brain plasticity is heterogeneous in mammals：Brain regeneration and repair are the dream of every neurobiologist as well as every common citizen in the world who knows that most neurological diseases,dementia and other age-related problems affecting the central nervous system（CNS）do represent a heavy health and social *** re-generative processes are not＂ a natural property of the mammalian CNS, rather, due to evolutionary constraints they seem substantially reduced （if compared to those occurring in non-mammalian vertebrates） and hardly inducible by therapeutic approaches （reviewed in Martino et al., 2011）.

关键词： PSA Figure dCX do large brains of long-living mammals prefer non-newly generated,immature neurons

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Effect of BaF2 addition on luminescence properties of Er3+/Yb3+ co-doped phosphate glasses

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Journal of Rare Earths 2018年第1期36卷 58-63页

作者： K.Linganna R.Narro-García P.Manasa H.desirena E.de la rosa C.K.Jayasankar department of Physics Sri Venkateswara University Advanced Optical Lens Research Center Korea Photonics Technology Institute (KOPTI) Centro de Física Aplicada y Tecnología Avanzada UNAM Centro de Investigaciones en Optica

Er3+/Yb3+co-doped phosphate glasses（P2O5-Al2O3-BaO-BaF2-K2O-Er2O3-Yb2O3） with varying BaF2content,were prepared by a conventional melt quenching technique and their spectroscopic properties were examined through the Raman, absorption, emission and.decay measurements. Raman spectra(350-1400 cm-1) of the Er3+/Yb3+co-doped phosphate glasses with varying BaF2content, were recorded upon laser excitation at 785 nm. Near infrared luminescence spectra were measured in the1400-1600 nm region under 970 nm diode laser excitation and characteristic band was observed at1533 nm corresponding to4Ⅰ13/2→4Ⅰ15/2transition of Er3+ion. The decay curves for the4Ⅰ13/2level of Er3+ion, were measured and the lifetime is found to decrease from 7.94 to 7.70 ms when BaF2content increases from 0 to 8 mol% and then increases up to 7.83 ms with further increase in BaF2content（12 mol%）. The emission *** and figure of merit for the4Ⅰ13/2→4Ⅰ15/2transition of Er3+ion were evaluated and compared to the other host matrices. The upconversion luminescence was measured and intense red emission was observed for all the studied samples.

关键词： Er3+/Yb3+co-doped phosphate glasses Raman spectra Absorption and emission cross-sections Lifetime Rare earths

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EFFECTS OF RIVER NETWORK WORKS ANd SOIL CONSERVATION MEASURES ON RESERVOIR SILTATION

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International Journal of Sediment Research 2007年第4期22卷 273-281页

作者： Bruno MOLINO rosa VIPARELLI Annamaria de VINCENZO Prof. Department of Environmental Physics and Engineering University of Basilicata 85100 Potenza Italy

Knowledge of the morphological dynamics of a water course is essential for management of reservoir siltation. With an example of sedimentation in a reservoir in Basilicata, Italy, this paper demonstrates the effect on reservoir siltation of the hydraulic works, which are aimed to reduce sediment transport along the fluvial network and to prevent part of the sediment discharge from reaching the lake. The effect depends on the river type and on the the geological features of river basin slopes. The paper also shows how mass erosion can significantly contribute to development of reservoir siltation. Finally, preliminary results are provided about the time needed for river training works to be effective.

关键词： Water resources management River hydraulic works Soil erosion landslide Reservoir siltation

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Assessment of lead pollution in topsoils of a southern Italy area: Analysis of urban and peri-urban environment

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Journal of Environmental Sciences 2015年第7期27卷 179-187页

作者： Ilaria Guagliardi domenico Cicchella rosanna de rosa Gabriele Buttafuoco department of Biology Ecology and Earth Sciences University of Calabria department of Science and Technology University of Sannio National Research Council of Italy Institute for Agricultural and Forest Systems in the Mediterranean (ISAFOM)

Exposure to lead（Pb） may affect adversely human health. Mapping soil Pb contents is essential to obtain a quantitative estimate of potential risk of Pb contamination. The main aim of this paper was to determine the soil Pb concentrations in the urban and peri-urban area of Cosenza-Rende to map their spatial distribution and assess the probability that soil Pb concentration exceeds a critical threshold that might cause concern for human *** were collected at 149 locations from residual and non-residual topsoil in gardens,parks, flower-beds, and agricultural fields. Fine earth fraction of soil samples was analyzed by X-ray Fluorescence spectrometry. Stochastic images generated by the sequential Gaussian simulation were jointly combined to calculate the probability of exceeding the critical threshold that could be used to delineate the potentially risky areas. Results showed areas in which Pb concentration values were higher to the Italian regulatory values. These polluted areas were quite large and likely, they could create a significant health risk for human beings and vegetation in the near future. The results demonstrated that the proposed approach can be used to study soil contamination to produce geochemical maps,and identify hot-spot areas for soil Pb concentration.

关键词： Urban and peri-urban soils Geochemistry Lead Soil pollution Stochastic simulation

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Estimation of aboveground biomass of arboreal species in the semi-arid region of Brazil using SAR(synthetic aperture radar)images

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Journal of Arid land 2023年第6期15卷 695-709页

作者： Janisson B de JESUS Tatiana M KUPLICH Íkaro d.de C BARRETO Fernando L HILLEBRANd Cristiano N da rosa Postgraduate Program in Remote Sensing Federal University of Rio Grande do SulCampus ValePorto Alegre 91501970Brazil National Institute for Space Research(INPE) COESU(Southern Spatial Coordination)Santa Maria 97105970Brazil Postgraduate Program Biometry and Applied Statistics Rural Federal University of PernambucoRecife 52171900Brazil Federal Institute of Education Science and Technology of Rio Grande do Sul(IFRS)Campus RolanteRolante 95690000Brazil Postgraduate Program in Remote Sensing Polar and Climate CenterFederal University of Rio Grande do SulPorto Alegre 91501970Brazil

The Caatinga biome is an important ecosystem in the semi-arid region of *** has significantly degraded due to human activities and is currently a region undergoing ***,monitoring the variation in the Caatinga biome has become essential for its sustainable ***,traditional methods for estimating aboveground biomass(AGB)are time-consuming and *** sensing,such as optical and radar imaging,can estimate and correlate with ***,radar imaging is still a novelty to be applied in estimating the AGB of this biome,which is an area with little ***,this study aimed to use Sentinel-1 images to estimate the AGB of the Caatinga biome in Sergipe State(northeastern Brazil)and to verify its influencing *** sample plots(30 m×30 m)were selected,and the stems of individuals with a circumference at breast height(1.3 m above the ground)equal to or greater than 6.0 cm were measured,and the AGB through an allometric equation was *** Sentinel-1 images from 3 different periods(green,intermediate,and dry periods)were used to consider the phenological conditions of the Caatinga *** the pre-processing and extraction of attributes(co-polarized VV(vertical transmit and vertical receive),cross-polarized VH(vertical transmit and horizontal receive),and band ratio VH/VV backscatter,radar vegetation index,dual polarization synthetic aperture radar(SAR)vegetation index(dPSVI),entropy(H),and alpha angle(α))were performed with Sentinel’s Application *** attributes were used to estimate the AGB through simple and multiple linear regressions and evaluated by the coefficients of determination(R2),correlation(r),and root mean squared error(RMSE).The results showed that the attributes individually had little ability to estimate the AGB of the Caatinga biome in the three *** with multiple regression,we found that the intermediate period presented the equation with the best

关键词： Caatinga tropical dry forest coherent and incoherent attributes C-band Sentinel-1

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