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Effect of Baobab (Adansonia digitata L.) Seeds Washing and Origin on Their Fatty Acids and Phenolic Compounds Oils Content
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作者 Alioune Sow Edouard Mbarick Ndiaye +9 位作者 Oumar Ibn Khatab Cissé Pape Guédel Faye Alé Kane Delphine Margout-Jantac Bou Ndiaye Samba Baldé Khadim Niane Nicolas Ayessou Patrick Poucheret Mady Cissé 《American Journal of Analytical Chemistry》 2025年第1期1-14,共14页
The aim of the present study was to evaluate the effects of baobab seed washing and origin on the chemical composition of the oil extracted by pressing. Six (6) oil samples were obtained from seeds of three (3) geogra... The aim of the present study was to evaluate the effects of baobab seed washing and origin on the chemical composition of the oil extracted by pressing. Six (6) oil samples were obtained from seeds of three (3) geographical origins. The identification and quantification of fatty acids and the polyphenolic profile were carried out by GC-MS and HPLC-UV, respectively. Analysis of fatty acid methyl esters allowed the identification and quantification of 18 fatty acids. Oils from unwashed seeds were richer in palmitic (C16:0), stearic (C18:0), oleic (C18:1) and arachidic (C20:0) acids. In addition, HPLC-UV analysis at 279 nm shows that oils from unwashed seeds are richer in tyrosol, hydroxytyrosol and caffeic acid. With regard to the polyphenolic profile, gallic acid and quercetin were not detected in these baobab oils. Principal component analysis of fatty acid and phenolic compound content showed that oils from unwashed seeds would best preserve their chemical and associated potential bioactive characteristics. 展开更多
关键词 Adansonia digitata L. SEEDS Extraction Pressure Oil Fatty Acids TYROSOL Hydroxytyrosol
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地中海涡旋的垂向结构与物理性质 被引量:7
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作者 陈江欣 宋海斌 +3 位作者 拜阳 Luis Pinheiro 黄兴辉 刘伯然 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2013年第3期943-952,共10页
本文利用地震海洋学新的反演结果,对地中海涡旋的温度、密度、声速以及波阻抗等物理性质进行了详细的分析与讨论,特别对地中海涡旋的一些细结构、混合过程进行了相关描述.研究分析取得以下认识:(1)涡旋具有涡旋核心水与涡旋混合水双层结... 本文利用地震海洋学新的反演结果,对地中海涡旋的温度、密度、声速以及波阻抗等物理性质进行了详细的分析与讨论,特别对地中海涡旋的一些细结构、混合过程进行了相关描述.研究分析取得以下认识:(1)涡旋具有涡旋核心水与涡旋混合水双层结构,这种结构特征可以在温度图、声速图和波阻抗图中识别出来;(2)涡旋核心水并不是均匀的稳定结构,内部有微弱的混合作用;(3)在涡旋上部以及周围边缘区域,海水的混合比较复杂;在涡旋下部边缘区域,除了有小尺度的盐指混合,内波也是非常重要的动力混合作用;(4)海水密度在涡旋核心水的分布比较稳定,成层性较强,在混合水区域由于不同的混合作用及其强烈程度不同,会发生波动甚至反转;(5)涡旋本身并不是一个严格对称的结构,涡旋与背景海水的上部以及周围边界比较模糊和复杂,而涡旋下部边界则比较明显.地震海洋学反演提供的涡旋物理性质数据能够为涡旋进一步的研究提供更为准确、更高精度以及更高分辨率的参考数据,同时对涡旋的运动学以及动力学研究提供了更进一步的研究方法和研究方向. 展开更多
关键词 地震海洋学 地中海涡旋 海水物理性质 细结构 混合
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利用反射地震数据和XBT数据联合反演海水的温盐分布 被引量:22
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作者 黄兴辉 宋海斌 +1 位作者 Luis M.Pinheiro 拜阳 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2011年第5期1293-1300,共8页
利用地震数据反演海水的温盐分布是地震海洋学研究的一个重要方向.本文分析了采集于伊比利亚半岛西南缘海域的GOLR12低频地震数据和同步观测的XBT(eXpendable BathyThermograph)、CTD(Conductivity-Temperature-Depth)资料,将叠后约束... 利用地震数据反演海水的温盐分布是地震海洋学研究的一个重要方向.本文分析了采集于伊比利亚半岛西南缘海域的GOLR12低频地震数据和同步观测的XBT(eXpendable BathyThermograph)、CTD(Conductivity-Temperature-Depth)资料,将叠后约束波阻抗反演方法应用到海水温度、盐度剖面的计算当中,计算结果显示这种反演方法可以提供水平分辨率为6.25m的温度和盐度资料,温度的精度约为0.16℃,可以为物理海洋学研究提供高横向分辨率的基础数据. 展开更多
关键词 地震海洋学 叠后反演 温盐分布 地中海涡旋
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海洋中尺度涡与内波的地震图像 被引量:21
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作者 宋海斌 Luis Pinheiro +3 位作者 王东晓 董崇志 宋洋 拜阳 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2009年第11期2775-2780,共6页
海洋反射地震通常用于调查、研究海底地质构造,勘探油气与天然气水合物资源.近期研究表明多道反射地震方法也可以对水柱的热盐细结构成像.中尺度涡与内波是重要的物理海洋现象,但是常规的物理海洋调查是在间隔若干公里的离散测站上进行... 海洋反射地震通常用于调查、研究海底地质构造,勘探油气与天然气水合物资源.近期研究表明多道反射地震方法也可以对水柱的热盐细结构成像.中尺度涡与内波是重要的物理海洋现象,但是常规的物理海洋调查是在间隔若干公里的离散测站上进行的,水平分辨率较低,因此对中尺度涡的结构与内波的横向分布了解较差.本文利用在大西洋东部、南海采集的地震数据给出了低频反射地震可以对中尺度涡与内波清晰成像的新的证据.反射地震方法较传统海洋观测手段,具有明显的优势,主要体现在高的水平分辨率和短时间内对整个海水剖面进行成像方面.从地震剖面上,能够清楚地观测到中尺度涡、内波造成的反射特征变化,从而有助于改进对能量在不同尺度的海水运动之间传递过程的认识. 展开更多
关键词 海洋反射地震 中尺度涡 海洋内波 南海 大西洋东部
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Siderophore-Producing Rhizobacteria as a Promising Tool for Empowering Plants to Cope with Iron Limitation in Saline Soils:A Review 被引量:7
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作者 Maria J.FERREIRA Helena SILVA Angela CUNHA 《Pedosphere》 SCIE CAS CSCD 2019年第4期409-420,共12页
Iron(Fe) bioavailability to plants is reduced in saline soils;however, the exact mechanisms underlying this effect are not yet completely understood. Siderophore-expressing rhizobacteria may represent a promising alte... Iron(Fe) bioavailability to plants is reduced in saline soils;however, the exact mechanisms underlying this effect are not yet completely understood. Siderophore-expressing rhizobacteria may represent a promising alternative to chemical fertilizers by simultaneously tackling salt-stress effects and Fe limitation in saline soils. In addition to draught, plants growing in arid soils face two other major challenges: high salinity and Fe deficiency. Salinity attenuates growth, affects plant physiology, and causes nutrient imbalance,which is, in fact, one of the major consequences of saline stress. Iron is a micronutrient essential for plant development, and it is required by several metalloenzymes involved in photosynthesis and respiration. Iron deficiency is associated with chlorosis and low crop productivity. The role of microbial siderophores in Fe supply to plants and the effect of plant growth-promoting rhizobacteria(PGPR) on the mitigation of saline stress in crop culture are well documented. However, the dual effect of siderophore-producing PGPR, both on salt stress and Fe limitation, is still poorly explored. This review provides a critical overview of the combined effects of Fe limitation and soil salinization as challenges to modern agriculture and intends to summarize some indirect evidence that argues in favour of siderophore-producing PGPR as biofertilization agents in salinized soils. Recent developments and future perspectives on the use of PGPR are discussed as clues to sustainable agricultural practices in the context of present and future climate change scenarios. 展开更多
关键词 ARIDITY BIOAVAILABILITY BIOFERTILIZER Fe deficiency high salinity plant growth-promoting rhizobacteria(PGPR) saline stress soil salinization
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Atmospheric River Signatures in Radiosonde Profiles and Reanalyses at the Dronning Maud Land Coast,East Antarctica 被引量:4
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作者 Irina V.GORODETSKAYA Tiago SILVA +1 位作者 Holger SCHMITHUSEN Naohiko HIRASAWA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第5期455-476,共22页
Atmospheric rivers(ARs)are an important component of the hydrological cycle linking moisture sources in lower latitudes to the Antarctic surface mass balance.We investigate AR signatures in the atmospheric vertical pr... Atmospheric rivers(ARs)are an important component of the hydrological cycle linking moisture sources in lower latitudes to the Antarctic surface mass balance.We investigate AR signatures in the atmospheric vertical profiles at the Dronning Maud Land coast,East Antarctica,using regular and extra radiosonde measurements conducted during the Year of Polar Prediction Special Observing Period November 2018 to February 2019.Prominent AR events affecting the locations of Neumayer and Syowa cause a strong increase in specific humidity extending through the mid-troposphere and a strong low-level jet(LLJ).At Neumayer,the peak in the moisture inversion(up to 4 g kg^?1)is observed between 800 and 900 hPa,while the LLJ(up to 32 m s^?1)is concentrated below 900 hPa.At Syowa the increase in humidity is less pronounced and peaks near the surface,while there is a substantial increase in wind speed(up to 40 m s?1)between 825 and 925 hPa.Moisture transport(MT)within the vertical profile during the ARs attains a maximum of 100 g kg?1 m s?1 at both locations,and is captured by both ERA-Interim and ERA5 reanalysis data at Neumayer,but is strongly underestimated at Syowa.Composites of the enhanced MT events during 2009?19 show that these events represent an extreme state of the lower-tropospheric profile compared to its median values with respect to temperature,humidity,wind speed and,consequently,MT.High temporal-and vertical-resolution radiosonde observations are important for understanding the contribution of these rare events to the total MT towards Antarctica and improving their representation in models. 展开更多
关键词 ANTARCTICA moisture transport RADIOSONDE observations YOPP-SOP-SH REANALYSIS
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Determination of 17<i>α</i>-Methyltestosterone in Freshwater Samples of Tilapia Farming by High Performance Liquid Chromatography 被引量:3
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作者 Isabel R. Barbosa Sara Lopes +3 位作者 Rhaul Oliveira Inês Domingues Amadeu M. V. M. Soares António J. A. Nogueira 《American Journal of Analytical Chemistry》 2013年第4期207-211,共5页
17α-methyltestosterone is used to induce the sex reversal of Tilapia sp. to obtain cultures mono-sex to an economically viable. This practice may lead to environmental contamination and problems in human health. Ther... 17α-methyltestosterone is used to induce the sex reversal of Tilapia sp. to obtain cultures mono-sex to an economically viable. This practice may lead to environmental contamination and problems in human health. Therefore methods need to be developed to detect residues of 17α-methyltestosterone in aqueous matrices. A simple high-performance liquid chromatographic method using ultraviolet detection (245 nm) and testosterone as internal standard has been developed for the monitoring 17α-methyltestosterone in freshwater samples of tilapia aquaculture. The method described involves limited sample preparation as it includes a filtration followed by a single solid-phase extraction step using C18 cartridge. Validation data indicated that the HPLC-UV method for 17α-methyltestosterone determination in the concentration range of 50 - 2000 μg/L provided good linearity, sensitivity, accuracy and precision. Method performance was efficiently applied to monitoring the freshwater samples of fish ponds and the surrounding aquatic channels. 展开更多
关键词 17α-Methyltestosterone High Performance Liquid Chromatography Environment TILAPIA FARMING
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High temperature X-ray diffraction study of the formation of Na_(2)Ti_(3)O_(7) from a mixture of sodium carbonate and titanium oxide 被引量:1
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作者 Caroline Piffet Bénédicte Vertruyen +3 位作者 Frédéric Hatert Rudi Cloots Frédéric Boschini Abdelfattah Mahmoud 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第2期210-218,共9页
Na2Ti3O7 has attracted much attention in the field of anode materials for Na-ion batteries thanks to its non-toxicity and very low working potential of 0.3 V vs Na0/Na+.Building a clearer picture of its formation from... Na2Ti3O7 has attracted much attention in the field of anode materials for Na-ion batteries thanks to its non-toxicity and very low working potential of 0.3 V vs Na0/Na+.Building a clearer picture of its formation from cheap Na_(2)CO_(3) and TiO_(2) starting materials is therefore of obvious interest.Here,we report new insights from an in-situ high temperature X-ray diffraction study conducted from room temperature to 800°C,complemented by ex-situ characterizations.We were thereby able to position the previously reported Na_(4)Ti_(5)O_(12) and Na_(2)Ti_(6)O_(13) intermediate phases in a reaction scheme involving three successive steps and temperature ranges.Shifts and/or broadening of a subset of the Na_(2)Ti_(6)O_(13) reflections suggested a combination of intra-layer disorder with the well-established ordering of successive layers.This in-situ study was carried out on reproducible mixtures of Na_(2)CO_(3) and TiO_(2) in 1:3 molar ratio prepared by spraydrying of mixed aqueous suspensions.Single-phase Na_(2)Ti_(3)O_(7) was obtained after only 8 h at 800°C in air,instead of a minimum of 20 h for a conventional solid-state route using the same precursors.Microstructure analysis revealed~15 mm diameter granules made up from rectangular rods of a fewmm length presenting electrochemical properties in line with expectations.In the absence of grinding or formation of intimate composites with conductive carbon,the specific capacity of 137 m Ah/g at C/5 decreased at higher rates. 展开更多
关键词 Formation mechanism High temperature XRD Na_(2)Ti_(3)O_(7) Spray-drying synthesis Na-ion batteries
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Colloidal(Gd0.98Nd0.02)2O3 nanothermometers operating in a cell culture medium within the first and second biological windows 被引量:2
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作者 M.L.Debasu H.Oliveira +1 位作者 J.Rocha L.D.Carlos 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第5期483-491,共9页
Non-contact,self-referenced and near-infrared luminescent nanothermometers have been recognized as emerging tools in the fields of nanomedicine and nanotechnology due to their great capability of precise temperature r... Non-contact,self-referenced and near-infrared luminescent nanothermometers have been recognized as emerging tools in the fields of nanomedicine and nanotechnology due to their great capability of precise temperature readout at the nanoscale and real-time deep-tissue imaging.However,the development of multifunctional and biocompatible luminescent nanothermometers operating within the optically transparent biological windows with high thermal sensitivity(>2.0%/K)remains challenging.Here,we present(Gd0.98Nd0.02)2O3 nanothermometers operated effectively within the first and second biological windows upon continuous-wave laser diode excitation at 808 nm.Ratiometric thermometric parameters are defined by the relative changes in the emission intensities originating from the two Stark components of the 4 F3/2 level(R2 and R1)to the 4 I9/2(900-1000 nm),4 I11/2(1035-1155 nm)and 4 I13/2(1300-1450 nm)multiplets.The thermo metric parameters are evaluated for colloidal samples in a cell culture medium and powder samples,and the highest thermal sensitivity(2.18%/K at 298 K)is attained for the former in the first biological window(both the excitation and emission in the 800-965 nm range).The repeatability and temperature uncertainty are 99%and 1.2 K,respectively.The nanothermometers are biocompatible with human MNT-1 melanoma and HaCaT cells for 24 h of exposure and nanoparticle concentration up to 0.400 mg/mL,showing their potential for applications in nanomedicine,e.g.,intracellular imaging and temperature mapping. 展开更多
关键词 GD2O3 Nd3^+-doped nanoparticles Luminescent nanothermometry Thermal sensitivity Cytotoxicity of nanoparticles Rare earths
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From the Challenges Imposed by Climate Change to the Preservation of Ecosystem Processes and Services 被引量:1
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作者 Rita Anastácio Mário Jorge Pereira 《Natural Resources》 2017年第12期788-807,共20页
Today, especially in countries that offer a satisfactory quality of life, it is easy to forget that we depend directly and indirectly on services provided by ecosystems such as quantity and quality of water, energy, f... Today, especially in countries that offer a satisfactory quality of life, it is easy to forget that we depend directly and indirectly on services provided by ecosystems such as quantity and quality of water, energy, food, health, and shelter. In less developed countries, the daily struggle for essential goods makes this dependency more real, despite the lack of knowledge, organization and/or financial resources to deal with the problems imposed on ecosystems by climate and anthropogenic changes. Protecting ecosystems by ensuring the services they provide has become highly dependent on our management capacity, our understanding of its functioning, and our capacity for persuasion. Demographic pressure and individualism compromise the survival of various species, including our own, and create pressures under governments and the stability of nations. The notion of facing a global challenge has awakened in the scientific community the need to focus on developing global strategies that change the mind-sets of decision makers, industry, governments and markets. Global knowledge networks and experts are being built to mitigate problems on a global scale. In this mini review, the authors make a brief visit to documents, intergovernmental initiatives, and platforms that have been built with the aim of contributing to promote a resolution for the global problems. 展开更多
关键词 ROADS to DIGNITY Essential BIODIVERSITY Variables KYOTO Protocol IPCC Ecosystem SERVICES Profile SDG’s
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PM_(2.5) chemical composition and health risks by inhalation near a chemical complex 被引量:3
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作者 Celia Alves Margarita Evtyugina +5 位作者 Estela Vicente Ana Vicente Ismael Casotti Rienda Ana Sanchez de la Campa Mario Tome Iola Duarte 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第2期860-874,共15页
Particulate matter(PM_(2.5))samples were collected in the vicinity of an industrial chemical pole and analysed for organic and elemental carbon(OC and EC),47 trace elements and around 150 organic constituents.On avera... Particulate matter(PM_(2.5))samples were collected in the vicinity of an industrial chemical pole and analysed for organic and elemental carbon(OC and EC),47 trace elements and around 150 organic constituents.On average,OC and EC accounted for 25.2% and 11.4% of the PM_(2.5) mass,respectively.Organic compounds comprised polycyclic aromatic hydrocarbons(PAHs),alkylated PAHs,anhydrosugars,phenolics,aromatic ketones,glycerol derivatives,aliphatic alcohols,sterols,and carboxyl groups,including aromatic,carboxylic and dicarboxylic acids.Enrichment factors>100 were obtained for Pb,Cd,Zn,Cu,Sn,B,Se,Bi,Sb and Mo,showing the contribution of industrial emissions and nearby major roads.Principal component analysis revealed that vehicle,industrial and biomass burning emissions accounted for 66%,11% and 9%,respectively,of the total PM_(2.5)-bound PAHs.Some of the detected organic constituents are likely associated with plasticiser ingredients and thermal stabilisers used in the manufacture of PVC and other plastics in the industrial complex.Photooxidation products of both anthropogenic(e.g.,toluene)and biogenic(e.g.,isoprene and pinenes)precursors were also observed.It was estimated that biomass burning accounted for 13.8%of the PM_(2.5) concentrations and that secondary OC represented 37.6% of the total OC.The lifetime cancer risk from inhalation exposure to PM_(2.5)-bound PAHs was found to be negligible,but it exceeded the threshold of 10−6 for metal(loi)s,mainly due to Cr and As. 展开更多
关键词 PM_(2.5) OC/EC Organic speciation Trace elements Cancer and non-cancer risks
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Urban Air Quality Plans and Integrated Assessment Methodologies 被引量:1
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作者 Ana Isabel Miranda Helder Relvas +7 位作者 Enrico Turrini Diogo Lopes Carlos Silveira Joana Ferreira Myriam Lopes Elisa Sa Carlos Borrego Marialuisa Volta 《Journal of Environmental Science and Engineering(B)》 2014年第2期70-78,共9页
The air quality directive (2008/50/EC (of the European Parliament and of the Council of 21 May 2008)) requires European Member States to design appropriate AQPs (air quality plans) for zones and agglomerations w... The air quality directive (2008/50/EC (of the European Parliament and of the Council of 21 May 2008)) requires European Member States to design appropriate AQPs (air quality plans) for zones and agglomerations where the air quality does not comply with the limit values and to assess possible emission reduction measures to decrease concentration levels. The Portuguese agglomeration of Porto Litoral is one of the several European Union urban areas that had to develop and implement AQPs to reduce particulate matter (PM10). The AQPs were initially designed based on a scenario approach and using an air quality model, which was applied over the study region for the reference situation with the current PM10 emissions, and for a reduction scenario with PM10 emissions re-estimated considering the implementation of abatement measures. Aiming to cost-efficiently optimize Porto Litoral PM10 abatement measures, the assessment procedure was repeated using an optimization approach based on the RIAT + (regional integrated assessment tool +). Porto Litoral urban area's technical and non-technical measures were characterized (including associated costs) and, through the application of the air quality model to 20 emissions abatement scenarios, S-R (source-receptor) relationships were created. This paper comparatively describes the air quality plans designed to improve PM10 levels in the Porto Litoral agglomeration based on both the scenario analysis and the optimization approach. 展开更多
关键词 Urban air quality air quality plans integrated assessment methodologies modelling tools
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Sea Turtle Nesting: What Is Known and What Are the Challenges under a Changing Climate Scenario 被引量:1
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作者 Raquel A. M. São Miguel Rita Anastácio Mário J. Pereira 《Open Journal of Ecology》 2022年第1期1-35,共35页
The rate of climate change experienced globally in recent decades may compromise sea turtles’ survival;especially temperature increase, which is particularly fast, impacts life history characteristics, such as temper... The rate of climate change experienced globally in recent decades may compromise sea turtles’ survival;especially temperature increase, which is particularly fast, impacts life history characteristics, such as temperature-dependent sex determination (TSD), late maturity and sea turtles highly migratory nature. This review aims to identify and summarize the information that has been collected from 2009-2020 in order to aid future empirical studies that seek to fill these and other knowledge gaps, and subsequently assist conservationists in making multilevel decisions to protect sea turtle populations and species. In a summarized way the general knowledge acquired so far on the influence of environmental abiotic and biotic factors on nesting behaviour and hatching, emergence and survival successes of sea turtle hatchlings, was gathered. To accomplish this work, a search on Web of Science, Science Direct, NCBI/PubMed, and Google Scholar was carried out using the terms “sea turtles + climate change”. Published articles in the period 2009-2020 were selected, related to the nesting ecology of 5 species of sea turtles: <em>Caretta caretta</em>, <em>Eretmochelys imbricata</em>, <em>Dermochelys coriacea</em>,<em> Chelonia mydas</em>, <em>Lepidochelys olivacea</em>. Emphasis was also placed on geographical information and on population location (e.g. climatic conditions during the nesting season). These articles (N = 126) were analysed giving relevance to researcher’s data interpretations, comparisons with other researches, and the reached conclusions. An attempt was made to represent all 5 species of sea turtles when selecting articles on each of the environmental factors that influence sea turtle nesting: temperature, humidity, nesting substrate, gases, depth of the nest, sea surface temperature (SST), nest location on the beach, nesting phenology and geographic distribution of nesting habitats. The interaction between these parameters and their consequences on the terrestrial phase of reproduction are presented and discussed. 展开更多
关键词 Reproductive Ecology Sea Turtles Climate Change Nesting Phenology and Geographic Distribution of Nesting Habitats
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Distinction between critical current effects and intrinsic anomalies in the point-contact Andreev reflection spectra of unconventional superconductors 被引量:1
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作者 Ge He Zhong-Xu Wei +12 位作者 Jérémy Brisbois Yan-Li Jia Yu-Long Huang Hua-Xue Zhou Shun-Li Ni Alejandro V Silhanek Lei Shan Bei-Yi Zhu Jie Yuan Xiao-Li Dong Fang Zhou Zhong-Xian Zhao Kui Jin 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第4期451-459,共9页
In this work,we discuss the origin of several anomalies present in the point-contact Andreev reflection spectra of(Li1-xFex)OHFeSe,LiTi2O4,and La2-xCexCuO4.While these features are similar to those stemming from int... In this work,we discuss the origin of several anomalies present in the point-contact Andreev reflection spectra of(Li1-xFex)OHFeSe,LiTi2O4,and La2-xCexCuO4.While these features are similar to those stemming from intrinsic superconducting properties,such as Andreev reflection,electron-boson coupling,multigap superconductivity,d-wave and p-wave pairing symmetry,they cannot be accounted for by the modified Blonder–Tinkham–Klapwijk(BTK) model,but require to consider critical current effects arising from the junction geometry.Our results point to the importance of tracking the evolution of the dips and peaks in the differential conductance as a function of the bias voltage,in order to correctly deduce the properties of the superconducting state. 展开更多
关键词 critical current effect point-contact Andreev reflection unconventional superconductor
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Effects of Seed Pretreatment on Germination, Growth and Yield of <i>Momordica charantia</i>L. 被引量:1
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作者 Samba Balde Nicolas Cyrille Ayessou +4 位作者 Antoine Sambou Khadim Niane Papa Guedel Faye Mady Cisse Codou Mar Diop 《Agricultural Sciences》 2021年第1期39-57,共19页
<em>Momordica charantia</em> is a plant species widely used in food and traditional medicine. However, the germination techniques and the performances of <em>M. charantia</em> are poorly unders... <em>Momordica charantia</em> is a plant species widely used in food and traditional medicine. However, the germination techniques and the performances of <em>M. charantia</em> are poorly understood by the populations. This study aims to better understand the germination, growth and development characteristics, and yield of <em>M. charantia</em>. Three pretreatments of the seeds are used for the shortening of the pre-germination period: soaking the seeds in tap water for 24 hours (batch 2), in hot water at 80<span style="white-space:nowrap;">&#730;</span>C (batch 3), for 24 hours and in the boiling water at 100<span style="white-space:nowrap;">&#730;</span>C for 24 hours (batch 4). A control without soaking (batch 1) was also carried out. The seeds were sown in plastic boxes in the laboratory with sterile sand and directly in the nursery in polyethylene sleeves. The influence of the light factor (light and dark) and watering frequency (every day and every two days) on the growth and yield parameters was evaluated respectively in the laboratory and in the nursery. Germination, growth and yield parameters were determined. The results show that the light and frequency of watering factors have no influence (p > 0.05) on the rate and duration of seed germination unlike pretreatments. Thus, Batch1 and 2 exhibit significantly higher germination rates (70% ± 16%) than Lots 3 and 4 (21% ± 15%) in the laboratory and in the nursery. On the other hand in terms of germination time, batch 3 and 4 displayed shorter durations (14 days) than those batch1 and 2 (23 days). Growth parameters and yield (fruit and seeds) are strongly influenced by watering frequency, unlike pretreatments which only affect yield. Growth and yield parameters are significantly higher with daily watering than daily watering. Ultimately, this study showed that pretreatments have an influence on the duration and rate of germination as well as the frequency of watering on the performance of <em>M. charantia</em>. 展开更多
关键词 Momordica charantia GERMINATION PERFORMANCE YIELD
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Evaluation of Phenolic Content and Antioxidant Activity of Aqueous Extracts of Three Carica papaya Varieties Cultivated in Senegal 被引量:1
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作者 Aissatou Alioune Gaye Oumar Ibn Khatab Cisse +3 位作者 Bou Ndiaye Nicolas Cyrille Ayessou Mady Cisse Codou Mar Diop 《Food and Nutrition Sciences》 2019年第3期276-289,共14页
The aqueous extracts of different parts (old leaves (OL), young leaves (YL), peels (PE) and delipidated seed residues (DS)) of three varieties of papaya are studied. Extraction conditions are optimized: an extraction ... The aqueous extracts of different parts (old leaves (OL), young leaves (YL), peels (PE) and delipidated seed residues (DS)) of three varieties of papaya are studied. Extraction conditions are optimized: an extraction time of 20 minutes, a temperature of 70°C and a plant material/water mixture of 1% give the best yield of polyphenol. The amount of polyphenols, flavonoids, saponins and proanthocyanins of each aqueous extract was investigated. Antioxidant activities are measured using two different methods (DPPH and ABTS). The delipidated seeds (DS) of V1 have the highest total phenolic content (TPC = 72.56 ± 3.16 mg GAE/g) while they have the lowest total flavonoid content (TFC = 0.22 ± 0.01). With regard to saponins, the PE of V3 is much richer in saponins (194.03 ± 15.78 mg AeE/g) than all the other extracts studied. The OL of V2 and PE of V1 contain the most proanthocyanidins with very similar values of 2.51 ± 0.03 mg CE/g and 2.53 ± 0.34 mg CE/g respectively. The study of the antioxidant activities of the extracts showed a correlation between the amount of polyphenols and IC50. DPPH OL and YL V2, which are rich in polyphenols, have the lowest IC50 of 0.072 mg/ml and 0.080 mg/ml respectively, whereas for ABTS we have PE of V1 that is very rich in polyphenols which has the smallest IC50 value of 0.218 mg/ml. 展开更多
关键词 Carica papaya Extraction Antioxidant POLYPHENOLS FLAVONOIDS PROANTHOCYANIDINS SAPONINS
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Physicochemical Characterization of Nine Cassava (<i>Manihot esculenta</i>Crantz) Cultivars from Chad 被引量:1
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作者 Djirabaye Nadjiam Nicolas Cyrille Ayessou Aliou Guissé 《Food and Nutrition Sciences》 2020年第7期741-756,共16页
In Chad, despite the multiple culinary uses of cassava leaves and tubers, their nutritional values are untapped. In this study, the physicochemical compositions and structure of nine cultivars were assessed. The prote... In Chad, despite the multiple culinary uses of cassava leaves and tubers, their nutritional values are untapped. In this study, the physicochemical compositions and structure of nine cultivars were assessed. The proteins were obtained by Kjeldahl’s method. Total sugars were determined according to the Luff-Schoorl method. For starch content, the polarimetric method of Earle and Milner was used. Mineral elements were carried out using an atomic absorption spectrophotometry. The cyanide was evaluated by the method of Williams and Edwards. Significant variability has been demonstrated in the leaves and dry tubers except for water content and dry matter. Analysis of the variances of the components of the tubers reveals that the water contents of the cultivars vary from 5.01% to 5.86%. The ash contents vary from 4.23% (cultivar DVA2) to 8.32% (cultivar DVL2). For total sugars, the values are between 53.63% (cultivar DVL2) and 57.99% (cultivars DVL12 and KA0303). The fiber contents are lower and vary from 1.74% (cultivar DVL12) to 1.92% (cultivars SB1366, DVA2, TL0101 and PG1314). The starch content varies from 28.93% (cultivar DVL12) to 31.05% (cultivar SB1366). The variations in mineral constituents of the tubers in mg/100g are Ca (145.21 - 250.08), Mg (83.89 - 165.22), P (147.34 - 360.78), K (1534.50 - 3064.09), Zn (0.75 - 0.82) and Mn (0.78 - 0.89). Iron concentrations are from 7.72 mg/100g (cultivar BA0909) to 60.62 mg/100g (cultivar DVA2</span><span style="font-family:Verdana;">)</span><span style="font-family:""><span style="font-family:Verdana;">. Analysis of the variances of the </span><span style="font-family:Verdana;">leaf constituents reveals high contents of Calcium for SB1366 (2108.41 mg/100g)</span><span style="font-family:Verdana;">, of iron (Fe 54.26 mg/100g) and potassium (K 1866.86 mg/100g) for DVL12, </span><span style="font-family:Verdana;">of phosphorus for TL0101 (471.87 mg/100g), of phosphorus (470.36 mg/100g)</span> <span style="font-family:Verdana;">and protein (30.74%) for PG1314, for magnesium for DVA2 (383.41 mg/100g)</span> <span style="font-family:Verdana;">and Copper for KA0303 (0.0147 mg/100g). The concentrations of hydrocyanic</span><span style="font-family:Verdana;"> acids are high in both leaves than fresh tubers (85 - 150 ppm). Lowest values are observed in tubers (10 - 15 ppm) for cultivar DVA2. Principal component analysis of the physicochemical characteristics of the leaves revealed four groups: the first very rich in calcium, magnesium and average potassium contents. Groups 2 and 3 are poor in calcium and magnesium but Group 2 </span><span style="font-family:Verdana;">ha</span></span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> the highest potassium content while Group 3 ha</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> an intermediate conten</span><span style="font-family:""><span style="font-family:Verdana;">t. Group 4 is very rich in calcium but low in magnesium and potassium. </span><span style="font-family:Verdana;">According to tubers, three groups have been identified which are characterized</span><span style="font-family:Verdana;"> by low, intermediate </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> high contents in phosphorus. Cultivars SB1366, DVA2, DVL2, TL0101 an</span><span style="font-family:Verdana;">d PG1314 show promising nutritional values and chemical constituents even if some have high levels of hydrocyanic acids. They could be recommended for the national selection program and for various applications. 展开更多
关键词 Physicochemical Constituents Leaves TUBERS CULTIVAR CASSAVA CHAD
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Diagnosing Ocean Tracer Transport from Sellafield and Dounreay by Equivalent Diffusion and Age
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作者 Steinar ORRE Yongqi GAO +1 位作者 Helge DRANGE Eric DELEERSNIJDER 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第5期805-814,共10页
A simple approach for estimating the equivalent diffusion for diagnosing tracer transport is proposed. Two different expressions are derived; one is based directly on an analytical solution of the two-dimensional adve... A simple approach for estimating the equivalent diffusion for diagnosing tracer transport is proposed. Two different expressions are derived; one is based directly on an analytical solution of the two-dimensional advection-diffusion equation, the other uses the variance of the tracer distribution. To illustrate some features of the equivalent diffusion and possible applications thereof, idealized releases of passive tracers from the nuclear fuel reprocessing plants at Sellafield in the Irish Sea and Dounreay on the northern coast of Scotland have been simulated with a regional isopycnic co-ordinate Ocean General Circulation Model. Both continuous and pulse releases are considered; the former being representative of the actual historical discharges from the reprocessing plants, the latter resembling an accidental scenario. Age tracers are included to calculate the mean time elapsed since the tracers left their source regions. It is found that in the Nordic Seas the age of tracers from Dounreay is approximately 2 years younger than the age from Sellafield. Although tracers from both sources eventually end up along the same transport routes, significant qualitative differences regarding the dispersion properties are found. It is argued that one single parameter, the equivalent horizontal diffusion, which is estimated to be in the range of 20 56 m^2 s^-1 from Sellafield and 170-485 m^2 s^-1 from Dounreay, determines these differences. 展开更多
关键词 equivalent diffusion passive tracers age tracers SELLAFIELD dounreay
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Spy out to Protect: Sensing Devices for Wildlife Virtual Fencing
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作者 Rita Anastácio Sérgio Cardoso Mário Jorge Pereira 《Open Journal of Ecology》 2018年第3期192-208,共17页
To avoid wildlife-human conflict several solutions are used, like electrical fences, the most expensive solution. Nowadays, technology enables alternative and cheaper approaches for conservation projects. A technologi... To avoid wildlife-human conflict several solutions are used, like electrical fences, the most expensive solution. Nowadays, technology enables alternative and cheaper approaches for conservation projects. A technological device was developed to detect elephants, moving on their habitat, and predict and react by avoiding confrontation with man. The devices were tested in field experiments, and proved to be efficient in capturing floor vibration, and air-sound signals. Collected data also enabled the estimation of the vibration-source by calculus (using triangulation), revealing the importance of the methodology for real-time location and tracking of high mass animals (e.g. elephants). Building up a mesh of devices, separated 25 m from each other, is estimated as possible to monitor and identify different animals (by discriminating patterns) in an area, like a virtual fencing system. Though the devices may be effective for animal behaviour research, or even animal communication analysis, or other Biology field, other applications outside Biology are possible for them, like monitoring of: rock-falling, micro seismic railway, infrastructures, and people movements. 展开更多
关键词 Micro-Electro-Mechanical Systems (MEMS) Microseismic Detection VIRTUAL FENCING FREE-RANGING WILDLIFE
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Water yield and biomass production for on a eucalypt-dominated Mediterranean catchment under different climate scenarios
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作者 Joao Rocha Ana Quintela +2 位作者 Dalila Serpa Jan Jacob Keizer Sérgio Fabres 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1263-1278,共16页
Worldwide,forests are vital in the regulation of the water cycle regulation and in water balance allocation.Knowledge of ecohydrological responses of production forests is essential to support management strategies,es... Worldwide,forests are vital in the regulation of the water cycle regulation and in water balance allocation.Knowledge of ecohydrological responses of production forests is essential to support management strategies,especially where water is already scarce.Shifting climatological patterns are expected to impact thermopluviometric regimes,water cycle components,hydrological responses,and plant physiology,evapotranspiration rates,crop productivity and land management operations.This work(1)assessed the impacts of different predicted climate conditions on water yield;(2)inferred the impacts of climate change on biomass production on eucalypt-to-eucalypt succes sion.To this end,the widely accepted Soil and Water Assessment Tool(SWAT)was run with the RCA,HIRHAM5 and RACMO climate models for two emission scenarios(RCP 4.5 and8.5).Three 12-year periods were considered to simulate tree growth under coppice regime.The results revealed an overall reduction in streamflow and water yield in the catchment in line with the projected reduction in total annual precipitation.Moreover,HIRHAM5 and RACMO models forecast a slight shift in seasonal streamflow of up to 2 months(for2024-2048)in line with the projected increase in precipitation from May to September.For biomass production,the extreme climate model(RCA)and severe emis sion scenario(RCP 8.5)predicted a decrease up to 46%.However,in the less extreme and more-correlated(with actual catchment climate conditions)climate models(RACMO and HIRHAM5)and in the less extreme emission scenario(RCP 4.5),biomass production increased(up to 20%),and the growth cycle was slightly reduced.SWAT was proven to be a valuable tool to assess climate change impacts on a eucalypt-dominated catchment and is a suitable decision-support tool for forest managers. 展开更多
关键词 Climate scenarios Forested catchments Forest ecohydrological modelling Eucalypt biomass production SWAT model
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