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Effect of Climate Variability on Yams (<i>Dioscorea spp</i>.) Production in Central and Northern Benin

American Journal of Climate Change 2020年第4期9卷 423-440页

作者： Fiacre Hermann Adifon Gilbert Atindogbé Daouda Orou Bello Ibouraïman Balogoun Ibouraïma Yabi Joseph Dossou léonard Ahoton Aliou saïdou Integrated Soil and Crop Management (ISCM) Unit Soil Sciences Laboratory School of Plant Production Sciences and Techniques Faculty of Agronomic Sciences University of Abomey-Calavi Cotonou Benin laboratory of Study and Research in Applied and Biometric Statistics (lERsaB) Faculty of Agronomic Sciences (FSA) of the University of Abomey-Calavi Cotonou Benin Plant Biology laboratory School of Plant Production Sciences and Techniques Faculty of Agronomic Sciences University of Abomey-Calavi Cotonou Benin Pierre PAGNEY laboratory “Climate Water Ecosystem and Development” University of Abomey-Calavi Faculty of Letters Arts and Human Sciences Department of Geography and Spatial Planning Cotonou Benin laboratory of Bioengineering of Food Processes (lABIOPA) Faculty of Agronomic Sciences (FSA) University of Abomey-Calavi Cotonou Benin

Climate change poses an important constraint to agricultural sector and food security in tropical African countries dominated by rain-fed agriculture. This research focuses on the effects of climate variability on yam production in central and northern Benin. Daily climate data such as temperatures, precipitation, potential evapotranspiration, relative humidity and insolation from 1981 to 2016 were collected at the direction of METEO-Benin. A survey was then conducted with 351 producers to collect their perceptions of the effect of climate variability on the yams production. Descriptive statistics, principal component analysis (PCA) followed by trend analyses, lamb index calculations and the agro-climatic stress index were carried out. The distribution of rain during the yam cycle (91.5% of those surveyed), the ambient temperature (84.9%), insolation (83.5%), the amount of rainwater that fell during the rainy season (82.2%) and the harmattan (53.3%) are perceived by sociolinguistic groups as climatic factors affecting the growth, the tuberization and yield of yams according to the producers. The results indicate an upward trend in temperature over the period 2001 to 2016 in the transition zone (28.4°C) and in the Northeast (27.76°C) and over the period from 2001 to 2011 in the North-West of Benin (27.71°C), where the average annual temperature during these periods is higher than normal (27.82°C in the center, 27.44°C in the Northeast and 27.42°C to the northwest). This research also shows an instability of the rains with a regular decrease in the rainfall in the Centre and the North-East of the country. The agro-climatic stress index (Isa) and above all the annual rainfall constitute the main climatic factors which determine

关键词： Yam Climate Variability Yield Food Security Benin

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基于压缩感知与尺度不变特征变换的图像配准算法

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光学学报 2014年第11期34卷 98-102页

作者：杨飒杨春玲广东第二师范学院物理系广东广州510310 华南理工大学电子与信息学院广东广州510640

尺度不变特征变换(SIFT)算法是图像配准中一种用来描述局部特征最稳健,使用最广泛的方法。针对存在关键点特征描述向量维数较高,算法计算复杂的问题,提出了一种基于稀疏随机投影(SRP)与SIFT相结合的图像配准算法,该算法把压缩感知理论... 详细信息

尺度不变特征变换(SIFT)算法是图像配准中一种用来描述局部特征最稳健,使用最广泛的方法。针对存在关键点特征描述向量维数较高,算法计算复杂的问题,提出了一种基于稀疏随机投影(SRP)与SIFT相结合的图像配准算法,该算法把压缩感知理论的稀疏特征表示概念引入SIFT算法中,即SRP-SIFT,用稀疏特征表示方法对SIFT关键点特征向量进行提取,再使用相应的l1距离度量进行特征向量的匹配。对新算法和相关SIFT算法进行了图像配准实验,实验结果表明,SRP-SIFT算法对包含复杂结构内容的图像配准性能优于传统SIFT算法,配准效率与几种改进的SIFT算法相当,但运算速度比传统SIFT算法和几种改进的SIFT算法有明显提高。

关键词：图像处理尺度不变特征变换压缩感知特征提取稀疏随机投影

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Impact of device resistances in the performance of graphene-based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期 89-99页

作者： óscar Castelló Sofía M.lópez Baptista kenji Watanabe Takashi Taniguchi Enrique Diez Jesús Enrique Velázquez-Pérez Yahya M.Meziani José M.Caridad Juan A.Delgado-Notario Department of Applied Physics University of Salamanca Unidad de Excelencia en luz y Materia Estructurada(lUMES) University of Salamanca Research Center for Electronic and Optical Materials National Institute for Materials Science Research Center for Materials Nanoarchitectonics National Institute for Materials Science Nanotechnology Group USAL–Nanolab University of Salamanca

In recent years, graphene field-effect-transistors(GFETs) have demonstrated an outstanding potential for terahertz(THz) photodetection due to their fast response and high-sensitivity. Such features are essential to enable emerging THz applications, including 6G wireless communications, quantum information, bioimaging and security. However, the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device, so-called access or parasitic resistances. In this work, we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFET detectors. Such dual-gate architectures allow us to fine tune(decrease) the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector, respectively. Our results can be well understood by a series resistance model, as shown by the excellent agreement found between the experimental data and theoretical calculations. These findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

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In-situ Raman observation on crack tips of Vickers indent in PlZT ceramics

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Transactions of Nonferrous Metals Society of China 2011年第10期21卷 2259-2263页

作者：张飒程璇张颍厦门大学材料学院福建省特种先进材料重点实验室厦门361005

Vickers indentation was introduced into the originally in-plane and out-of-plane poled PlZT *** Raman spectra were in-situ recorded at selected crack tips before and after the indentations,as well as after the applications of external electric *** results show that the changes in Raman intensities of optical modes could be sensitively related to 90° domain switching around the crack tips which are strongly dependent on the directions of original polarization and geometric *** the direction of electric field was perpendicular to the direction of original polarization,the 90° domain switching at crack tips of the Vickers indentation on the originally in-plane poled PlZT ceramics caused most significant change in the Raman intensity,which inhibited the crack ***,when the direction of electric field was parallel to the direction of original polarization,the growth of crack tips became predominantly without the 90° domain switching,which led to the crack growth.

关键词： ferroelectric ceramics domain switching in-situ Raman spectroscopy Vickers indentation

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急性肝衰竭小鼠血清TNFα与血脑屏障通透性的改变

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中国医科大学学报 2011年第8期40卷 681-683页

作者：王文吕飒周莹刘沛中国医科大学附属第一医院传染科沈阳110001 北京302医院生物治疗研究中心北京100039

目的探讨对乙酰氨基酚/扑热息痛(APAP)导致的急性肝衰竭(AlF)小鼠模型中血清肿瘤坏死因子α(TNFα)及血脑屏障(BBB)通透性的改变。方法应用APAP建立AlF小鼠模型,观察死亡率、血清丙氨酸氨基转移酶(AlT)及TNFα含量及肝组织病理学变化。... 详细信息

目的探讨对乙酰氨基酚/扑热息痛(APAP)导致的急性肝衰竭(AlF)小鼠模型中血清肿瘤坏死因子α(TNFα)及血脑屏障(BBB)通透性的改变。方法应用APAP建立AlF小鼠模型,观察死亡率、血清丙氨酸氨基转移酶(AlT)及TNFα含量及肝组织病理学变化。利用伊文思蓝(EB)在脑中含量检测BBB通透性。结果小鼠注射APAP后4 h开始死亡,6 h死亡率达到高峰。血清AlT水平2 h开始升高,9 h达到高峰。肝脏病理学9 h病变最重,表现为大块或亚大块出血性坏死。6 h组血清TNFα较0小时组显著升高。脑组织EB含量于2 h开始升高,6 h达到高峰。结论在APAP所致的AlF动物模型中,血清TNFα水平明显增高,且与脑组织EB含量的显著升高相一致。TNFα可能是导致AlF时BBB通透性增加的重要细胞因子。

关键词：急性肝衰竭肿瘤坏死因子血脑屏障

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HYDRO-PACIAE:Hydrodynamic and Transport Hybrid Model for Ultra-relativistic Heavy Ion Collisions

HYDRO-PACIAE:Hydrodynamic and Transport Hybrid Model for Ult...

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作者： YAN Yu-liang CHENG Yun ZHOU Dai-mei DONG Bao-guo CAI Xu l.P.Csernai sa Ben-hao Department of Nuclear Physics Institute of Particle Physics Huazhong Normal University Department of Physics and Technology University of Bergen

Combining the particle in cell hydrodynamic model and the PACIAE transport model,we present the HYDRO-PACIAE hybrid model and then use it to investigate,as an example,the charged particle

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Combined Radiometric Analysis Related to Guava leaf Phenology in Response to Soil Application of Paclobutrazol (PBZ)

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International Journal of Geosciences 2022年第8期13卷 681-694页

作者： Victor Manuel Rodríguez-Moreno Victor Manuel Rodríguez-Moreno José saúl Padilla-Ramírez Guillermo Medina-García Arturo Reyes-González Experimental Field Station “Pabellón” Km 32.5 highway Ags-Zac Pabellón de Arteaga Aguascalientes México Experimental Field Station “Zacatecas” Km 24.5 highway Zacatecas-Fresnillo Calera de Victor Rosales Zac. México Experimental Field Station “la laguna” Boulevard José Santos Valdez 1200 Pte Matamoros Coahuila México

The leaf-response to three-soil applied treatments of Paclobutrazol (PBZ;1000, 2000 and 0 ppm-control) was studied in a high-density plantation of eight guava (Psidium guajava) genotypes trees. All materials were prunned in vase form, with two to three major branches, yearly prunning for triggering the annual production cycle, and average height of 2.0 m. The dataset comprises fourth radiometric indices highly related to plant physiological activities. The dataset model took into account data collection dates, guava genotypes, and the positional effect of sun radiation on leaves based on their proximity to the canopy level and downward to the base of the woody seasonal-branch. Unexpectedly, there were no significant differences (NS) in PBZ treatments for genotypes, leaf position and radiometric indices. Analysis of the radiometric indices data revealed that anthocyanin (ARI index) and chlorophyll (PRI index) have a strong inverse relationship. Significant differences (P ≤ 0.05) were found between guava genotypes, and anthocyanin content;these results show that guava genotypes have varied responses, which could derive in their classification based-on drought resistance or low water requirements, however, it is important to note that additional research is required to determine the scope of these indications.

关键词： Radiometric Indices PBZ Guava High-Density Plantation Climate Change

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板桥凹陷原油轻烃地球化学特征

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天然气地球科学 2014年第8期25卷 1218-1225,1274页

作者：任拥军吕琳柳飒周立宏蒲秀刚中国石油大学地球科学与技术学院山东青岛266580 中国石油大港油田公司勘探事业部天津300280 中国石油大港油田公司勘探开发研究院天津300280

黄骅坳陷板桥凹陷原油轻烃整体表现为富链烷烃、贫芳烃和环烷烃含量相对较高的特征。C7和C6轻烃参数一致指示原油母源有明显高等植物有机质的输入,母质类型为混合型。庚烷值和异庚烷值较高,原油生成温度在108.7～129.8℃之间,说明原油... 详细信息

黄骅坳陷板桥凹陷原油轻烃整体表现为富链烷烃、贫芳烃和环烷烃含量相对较高的特征。C7和C6轻烃参数一致指示原油母源有明显高等植物有机质的输入,母质类型为混合型。庚烷值和异庚烷值较高,原油生成温度在108.7～129.8℃之间,说明原油主要为成熟阶段的产物。Mango参数k1值大致在1.0附近,符合轻烃稳态催化理论;k2值较高,源岩具有淡水湖相沉积的特点。碳环优势指数六环优势明显,指示出陆相原油的特点。根据轻烃参数特征可将研究区原油分为：来源于典型混合型有机母源的正常成熟原油、生物降解型原油以及来源于偏腐泥型母质的特殊成因原油3种类型。

关键词：板桥凹陷轻烃成熟度 Mango参数成因类型

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有关风险、信任和知识的话题:以哈兰德萨斯隧道为例

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AMBIO－人类环境杂志 1999年第6期28卷 558-562页

作者： sa Boholm Ragnar lfstedt 刘乃隆 Centre for Public Sector Research(CEFOS) Gteborg University Box 720 SE-405 30 Gteborg Sweden Centre for Environmental Strategy University of Surrey Guilford Surrey GU2 5XHUK

由于种种原因,凡是一些对于当地社区以及环境会有重大影响的大型工厂或基础建设项目,总会引起激烈的争议。本文论述在瑞典南部一条穿过哈兰德萨斯(Hallandsas)山岭的大型铁路隧道工程中当地社区的反应。现代工业社会中的一项关键问题是... 详细信息

由于种种原因,凡是一些对于当地社区以及环境会有重大影响的大型工厂或基础建设项目,总会引起激烈的争议。本文论述在瑞典南部一条穿过哈兰德萨斯(Hallandsas)山岭的大型铁路隧道工程中当地社区的反应。现代工业社会中的一项关键问题是,由国家设计和批准的认为发展经济所必需的项目如何能够在一个在时间和空间上有着特殊的历史和传统意义的环境中得以实施。本文以哈兰德萨斯隧道工程为例,对有关风险意识问题、对政府部门、工业和管理部门的信任问题以及各个集团认为有关的知识进行讨论。

关键词：哈兰德萨斯隧道工程选址交通设施基础建设

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Dietary Iodine Intake in the Chinese Population

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Biomedical and Environmental Sciences 2011年第6期24卷 617-623页

作者： SUI Hai Xia lI Jian Wen MAO Wei Feng ZHU Jiang Hui HE Yu Na SONG Xiao Yu MA Ning ZHANG lei lIU sa Na lIU Zhao Ping lI Feng Qin National Institute of Nutrition and Food safety China CDC Beijing 100021 China

Objective To evaluate dietary iodine intake and its potential risks among the Chinese population Methods Individual dietary iodine intake was calculated using food consumption data multiplying by iodine concentration in foods, table salt and drinking water, followed by summing, and then compared with the corresponding age-specific reference values, including Upper Intake level （Ul） and Recommended Nutrient Intake （RNI）. Results In areas with water iodine concentration （Wl） lower than 150 ug/l, 80.8% of residents had iodine intake between the RNI and Ul, 5.8% higher than Ul, and the remaining （13.4%） lower than RNI if iodized salt was consumed. However, in the uniodized salt consumption scenario, only 1.0% of residents between RNI and Ul, 1.4% higher than Ul, and a large part of residents （97.6%） lower than RNI. In areas with Wl higher than 150 ug/l ,all residents had iodine intake between RNI and Ul if iodized salt was consumed, except 10.5% and 24.9% of residents higher than Ul in areas with Wl at 150-300 ug/l and higher than 300 ug/l respectively. However, in the uniodized salt consumption scenario, only 1.5% and 1.7% of residents had higher iodine intake than Ul respectively. Conclusion The findings suggested that in general, the dietary iodine intake by the Chinese population was appropriate and safe at the present stage. People in areas with WI lower than 150 ug/l were more likely to have iodine deficiency. While people in areas with WI higher than 150 ug/l were more likely to have excessive iodine intake if iodized salt was consumed.

关键词： Iodine Exposure assessment Drinking water Iodine Dietary Iodine Intake

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