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Validating a dust production model by field experiment in Mu Us Desert, China

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Chinese Science Bulletin 2006年第7期51卷 878-884页

作者： MEI Fanmin j. Rajot S. alfaro L. Gomes ZHANG Xiaoye WANG Tao Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi'an 710075 China Department of Environmental Science and Technology Xi'an University of Engineering and Technology Xi'an 710048 China Center of Monitoring and Forecasting of Chemical Components of Atmosphere State Key Laboratory of Atmospheric Chemistry Institute of National Meteorology Research Beijing 100081 China Laboratoire lnteruniversitaire des Systemes Atmospheriques Universite de Paris 12 Paris 94010 France

Field experiments of dust production have been seldom performed in Chinese deserts that are identified as one of main dust sources in the world, and such an experiment to validate a dust production model (DPM) has not been made in China until now. Saltation flux, dust emission flux, surface features and meteorological parameters (U*, Z0, Ri, etc.) were investigated in Mu Us Desert of China to verify the DPM model and accumulate dust emission data during the spring of 2002. It indicates that observed saltation fluxes from 0.07 to 8.00 g·m?1·s?1 are in good agreement with the ones predicted by the DPM model when the constant of the saltation flux equation is tuned to about 2.61, which corresponds to wind fric- tion velocities from 0.26 to 0.35 m·s?1. Unfortunately, during three local dust emission events, the observed dust fluxes are from 1 to 3 μg· m?2· s?1, lower than the modeled ones, implying that the model needs to be improved further under lower wind velocity. In comparison with data from a sandy soil with physical crust and a loam soil, saltation fluxes of the loose sandy soil in Mu Us Desert are obviously higher, which suggests that deserts and sandy land with desertification are major dust sources in northern China.

关键词：沙漠尘埃模拟野外试验

Tree growth is more limited by drought in rear-edge forests most of the times

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Forest Ecosystems 2021年第2期8卷 330-344页

作者： j.julio Camarero Antonio Gazol Gabriel Sangüesa-Barreda Marta Vergarechea Raquel alfaro-Sánchez Nicolás Cattaneo Sergio M.Vicente-Serrano Instituto Pirenaico de Ecología(IPE-CSIC) Avda.Montañana 1005E-50192 ZaragozaSpain Ei FAB-iu FOR University of ValladolidCampus Duques de SoriaE-42004 SoriaSpain NIBIO Norwegian Institute of Bioeconomy ResearchPostboks 155NO-1431ÅsNorway Department of Biology Wilfrid Laurier UniversityN2L 3C575 Univ.Avenue WWaterlooOntarioCanada

Background:Equatorward,rear-edge tree populations are natural monitors to estimate species vulnerability to climate *** to biogeographical theory,exposition to drought events increases with increasing aridity towards the equator and the growth of southern tree populations will be more vulnerable to drought than in central ***,the ecological and biogeographical margins can mismatch due to the impact of ecological factors(topography,soils)or tree-species acclimation that can blur large-scale geographical imprints in trees responses to drought making northern populations more drought ***:We tested these ideas in six tree species,three angiosperms(Fagus sylvatica,Quercus robur,Quercus petraea)and three gymnosperms(Abies alba,Pinus sylvestris and Pinus uncinata)by comparing rear-edge tree populations subjected to different degrees of *** used dendrochronology to compare the radial-growth patterns of these species in northern,intermediate,and southern tree populations at the continental rear *** and conclusions:We found marked variations in growth variability between species with coherent patterns of stronger drought signals in the tree-ring series of the southern populations of ***,***,and *** was also observed in species from cool-wet sites(*** and ***),despite their limited responsiveness to ***,in the case of *** the intermediate population showed the strongest relationship to *** drought-sensitive species as *** and ***,southern populations presented more variable growth which was enhanced by cool-wet conditions from late spring to *** found a trend of enhanced vulnerability to drought in these two *** response of tree growth to drought has a marked biogeographical component characterized by increased drought sensitivity in southern populations even within the species distribution rear ***,the relationship

关键词： Climate change Dendroecology Latitudinal gradient Mediterranean forests Standardized evapotranspiration precipitation index(SPEI)

Vigorous,but differential mononuclear cell response of cirrhotic patients to bacterial ligands

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World journal of Gastroenterology 2011年第10期17卷 1317-1325页

作者： Varenka j Barbero-Becerra María Concepción Gutiérrez-Ruiz Carmen Maldonado-Bernal Félix I Téllez-Avila Roberto alfaro-Lara Florencia Vargas-Vorácková Department of Gastroenterology Instituto Nacional de Ciencias Médicasy Nutrición Salvador Zubirán Laboratorio de Fisiología Celular División de Ciencias de la Salud Universidad Autónoma Metropolitana-Iztapalapa Unidad de Investigación Médica en Enfermedades Infecciosasy Parasitarias Hospital de Pediatría Unidad de Investigación en Enfermedades Oncológicas Hospital Infantil de México Federico Gómez

AIM: To study the role of gram-positive and gram-negative bacteria in the pathogenesis of liver injury, specifically the activation of inflammatory mediators. METHODS: Peripheral blood mononuclear cells of 20 out-patients were studied, 10 of them with *** blood mononuclear cells were isolated and exposed to lipopolysaccharide or lipoteichoic acid. CD14, Toll-like receptor 2 and 4 expression was determined by flow cytometry, and tumor necrosis factor (TNF) α, interleukin (IL)-1β, IL-6, IL-12 and IL-10 secretion in supernatants was determined by ELISA. RESULTS: Higher CD14, Toll-like receptor 2 and 4 expression was observed in peripheral blood mononuclear cells from cirrhotic patients, (P < 0.01, P < 0.006, P < 0.111) respectively. Lipopolysaccharide and lipoteichoic acid induced a further increase in CD14 expression (P < 0.111 lipopolysaccharide, P < 0.013 lipoteichoic acid), and a decrease in Toll-like receptor 2 (P < 0.008 lipopolysaccharide, P < 0.008 lipoteichoic acid) and Toll-like receptor 4 (P < 0.008 lipopolysaccharide, P < 0.028 lipoteichoic acid) expression. With the exception of TNFα, absolute cytokine secretion of peripheral blood mononuclear cells was lower in cirrhotic patients under nonexposure conditions (P < 0.070 IL-6, P < 0.009 IL-1β, P < 0.022 IL-12). Once exposed to lipopolysaccharide or lipoteichoic acid, absolute cytokine secretion of peripheral blood mononuclear cells was similar in cirrhotic and non-cirrhotic patients, determining a more vigorous response in the former (P < 0.005 TNFα, IL-1β, IL-6, IL-2 and IL-10 lipopolysaccharide; P < 0.037 TNFα; P < 0.006 IL-1β; P < 0.005 IL-6; P < 0.007 IL-12; P < 0.014 IL-10 lipoteichoic acid). Response of peripheral blood mononuclear cells was more intense after lipopolysaccharide than after lipoteichoic acid exposure. CONCLUSION: Peripheral blood mononuclear cells of cirrhotic patients are able to respond to a sudden bacterial ligand exposure, particularly lipopolysaccharide, suggestin

关键词：单核细胞肝硬化细菌性患者外周血单个核细胞 Toll样受体4 配体肿瘤坏死因子

Boron nitride nanoresonators for phonon-enhanced molecular vibrational spectroscopy at the strong coupling limit

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Light(Science & Applications) 2017年第1期6卷 55-62页

作者： Marta Autore Peining Li Irene Dolado Francisco j alfaro-Mozaz Ruben Esteban Ainhoa Atxabal Fèlix Casanova Luis E Hueso Pablo Alonso-González javier Aizpurua Alexey Y Nikitin Saül Vélez Rainer Hillenbrand CIC nanoGUNE Donostia-San Sebastián 20018Spain Donostia International Physics Center(DIPC) Donostia-San Sebastián 20018Spain IKERBASQUE Basque Foundation for ScienceBilbao 48013Spain Departamento de Física Universidad de OviedoOviedo 33007Spain Centro de Física de Materiales(MPC CSIC-UPV/EHU)Donostia-San Sebastián 20018Spain Current address:Department of Materials ETH ZürichZürich 8093Switzerland CIC nanoGUNE and UPV/EHU Donostia-San Sebastián 20018Spain

Enhanced light-matter interactions are the basis of surface-enhanced infrared absorption(SEIRA)spectroscopy,and conventionally rely on plasmonic materials and their capability to focus light to nanoscale spot *** polariton nanoresonators made of polar crystals could represent an interesting alternative,since they exhibit large quality factors,which go far beyond those of their plasmonic *** recent emergence of van der Waals crystals enables the fabrication of highquality nanophotonic resonators based on phonon polaritons,as reported for the prototypical infrared-phononic material hexagonal boron nitride(h-BN).In this work we use,for the first time,phonon-polariton-resonant h-BN ribbons for SEIRA spectroscopy of small amounts of organic molecules in Fourier transform infrared ***,the interaction between phonon polaritons and molecular vibrations reaches experimentally the onset of the strong coupling regime,while numerical simulations predict that vibrational strong coupling can be fully *** polariton nanoresonators thus could become a viable platform for sensing,local control of chemical reactivity and infrared quantum cavity optics experiments.

关键词： boron nitride phonon polaritons strong coupling surface-enhanced infrared absorption spectroscopy SEIRA

平坦沙地的空气动力学粗糙度变化及其物理意义

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自然科学进展 2006年第3期16卷 325-330页

作者：梅凡民 j.Rajot S.alfaro 张小曳王涛中国科学院寒区旱区环境与工程研究所沙漠与沙漠化重点实验室中国气象科学研究院大气边界层物理和大气化学国家重点实验室北京100081 中国科学院地球环境研究所黄土与第四纪地质国家重点实验室西安710075 Laboratoire Interuniversitaire des Systèmes Atmosphèriques 西安工程科技学院环境工程与环境科学系西安710048

利用风温廓线法测定了不同大气稳定度下的空气动力学粗糙度,以跃移传感器(saltiphone)记录的瞬时最小跃移通量观测瞬时起动摩阻风速．观测数据表明:空气动力学粗糙度随着大气稳定度变化而呈现明显的变化,近中性层结下其平均值在(1．2-4... 详细信息

利用风温廓线法测定了不同大气稳定度下的空气动力学粗糙度,以跃移传感器(saltiphone)记录的瞬时最小跃移通量观测瞬时起动摩阻风速．观测数据表明:空气动力学粗糙度随着大气稳定度变化而呈现明显的变化,近中性层结下其平均值在(1．2-4．5)×10-5m之间,不稳定层结的平均值在 (0．5-1．1)×10-4m之间,稳定层结的平均值在3×10-5-2×10-5m之间,不稳定层结空气动力学粗糙度高,稳定层结的低,近中性层结介于两者之间;3种大气稳定度下跃移过程的平均空气动力学粗糙度高于无跃移过程,近中性层结无跃移过程的平均空气动力学粗糙度在1-3×10-5m之间;野外测定的每日平均起动摩阻风速在0．19-0．26 m·s-1之间变化．观测与模拟结果表明近中性层结-地表无跃移过程下测定的空气动力学粗糙度对起动摩阻风速是有效的,而非中性层结下测定的空气动力学粗糙度对起动摩阻风速对起动摩阻风速的作用不显著,这能够从物理机制上得到说明．大气稳定度虽然对起动摩阻风速影响不大,但是否影响到风蚀强度还需要进一步的研究．

关键词：沙地空气动力学粗糙度摩阻风速起动摩阻风速大气稳定度

毛乌素沙地的粉尘释放通量观测及DPM模型的野外验证

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科学通报 2006年第11期51卷 1326-1332页

作者：梅凡民 j．Rajot S．alfaro L．Gomes 张小曳王涛中国科学院寒区旱区环境与工程研究所沙漠与沙漠化重点实验室 Laboratoire Interuniversitaire des Systèmes Atmosphèriques Universitè de Paris 12 Paris 94010France 中国气象局大气成分观测与服务中心中国气象局大气化学重点开放实验室

目前关于中国粉尘源区的释放通量观测数据很少,被经常使用的DPM粉尘释放模型在中国源区的可靠性还没有得到验证．2002年春季在毛乌素沙地开展了野外观测实验,分别观测了跃移通量、<10μm的粉尘释放通量、温度和风速梯度．观测期间平均... 详细信息

目前关于中国粉尘源区的释放通量观测数据很少,被经常使用的DPM粉尘释放模型在中国源区的可靠性还没有得到验证．2002年春季在毛乌素沙地开展了野外观测实验,分别观测了跃移通量、<10μm的粉尘释放通量、温度和风速梯度．观测期间平均摩阻风速在0．26-0．35 m．s-1之间,实测的跃移通量约在0．07～8．00 g·m-1·s-1之间,实测和模拟的跃移通量较为一致,跃移通量方程经验系数取2．61比较合适;在3次局地的粉尘释放过程中,实测的粉尘释放通量约在1～3μg·m-2·s-1之间,模拟的粉尘释放通量偏高,说明该模型在低风速条件下还需要校正．通过与前人数据的比较,发现松散的砂质土的跃移通量大于具有物理结皮的砂质土和存在大土壤团块的壤质土,说明在相同摩阻风速条件下,松散的砂质土的粉尘释放通量最大,预示中国北方粉尘的主要源地在沙漠和沙漠化的土地．

关键词：毛乌素沙地粉尘释放通量观测模型验证

2011年5月11日西班牙东南洛尔卡M_W5.1地震诱发的大范围滑坡

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世界地震译丛 2013年第3期44卷 66-80页

作者： P.alfaro j.Delgado F.j.García-Tortosa L.Lenti j.A.López C.López-Casado S.Martino 许冲中国地震局地质研究所

2011年5月11日，一个中等震级地震（Mw5．1）袭击了西班牙东南部洛尔卡城和邻近地区，造成了显著的破坏和人员伤亡。通过地震影响区的野外考察对250多处主要是碎裂型（岩／土崩塌、碎裂的土质滑坡和岩崩）诱发滑坡进行了定点和特征描述... 详细信息

2011年5月11日，一个中等震级地震（Mw5．1）袭击了西班牙东南部洛尔卡城和邻近地区，造成了显著的破坏和人员伤亡。通过地震影响区的野外考察对250多处主要是碎裂型（岩／土崩塌、碎裂的土质滑坡和岩崩）诱发滑坡进行了定点和特征描述。与以前该区域相似震级（Mw4．7～5．0）的地震事件，以及以前预测地震期间斜坡表现的模型结果相比，本次地震诱发滑坡的数量相当大。提出了几个原因来解释这种差异：（1）地震序列中相对高震级（Mw4．5）的前震可能弱化了区域内的斜坡强度；（2）这些事件产生了高的地震动峰值；（3）发生了地形场地效应。本研究的结果指出了在改进区域斜坡特征研究模型时考虑这些影响的重要性。

关键词：地震诱发滑坡滑坡编目浅源地震中等震级地形场地效应洛尔卡

双能量多层CT碘定量区别肾透明细胞癌与肾乳头状细胞癌:一项多阅片者诊断效能研究

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国际医学放射学杂志 2015年第1期 76-77页

作者： A.Mileto D.Marin M.alfaro-Cordoba j.C.Ramirez-Giraldo C.D.Eusemann E.Scribano Department of Radiology Duke University Medical Center

目的研究双能量多层CT成像碘量化是否能区别肾透明细胞癌和肾乳头状细胞癌亚型。材料与方法这项回顾性研究遵从HIPAA,通过机构审查委员会批准。本研究纳

关键词：肾透明细胞癌乳头状双能量 CT

DIFFERENCE IN PULSE AMPLITUD PER- FUSION PRESSURE AND PULSATIL OCU-LAR BLOOD FLOW BETWEEN HEALTHY INDIVIDUALS AND POAG PATIENTS IN MEXICO

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国际眼科杂志 2003年第1期3卷 13-13页

作者： G.alfaro j.jimenez M.Moreno j.Fromow M.E.Anaya Asociacion Mexicana de Glaucoma Sociedad Mexicana de Glaucoma Mexico and American A-cademy of Ophthalmology USAAsociacion Mexicana de Glaucoma Sociedad Mexicana de Glaucoma Mexico and American A-cademy of Ophthalmology USAAsociacion Mexicana de Glaucoma Sociedad Mexicana de Glaucoma Mexico and American A-cademy of Ophthalmology USAAsociacion Mexicana de Glaucoma Sociedad Mexicana de Glaucoma Mexico and American A-cademy of Ophthalmology USASociedad Mexicana de Glaucoma Mexico

To determine the pulse amplitude, ocular puslatile blood flow and perfusion pressure, we use the OBF pneumotonometer in healthy individuals and in patients with open angle glaucoma. Once determine the results compare it and show the experience in mexicans. The hypothesis is that the healthy individuals have higher pulse amplitud, pulsatile ocular blood flow and

关键词：原发性开角型青光眼健康眼墨西哥脉冲幅度灌流压眼内血流