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Vegetation productivity responses to drought on tribal lands in the four corners region of the Southwest USA

Frontiers of Earth Science 2018年第1期12卷 37-51页

作者： Mohamed Abd Salam el-VILALY Kamel DIDAN Stuart E. MARSH Willem j.D. VAN LEEUWEN Michael A. CRIMMINS Armando Barreto MUNOZ The Intemational Food Policy Research Institute Washington DC 20006-1002 USA Vegetation Index and Phenology Lab Department of Agricultural and Biosystems Engineering The University of Arizona Tucson AZ 85721-0036 USA Arizona Remote Sensing Center School of Natural Resources and the Environment The University of Arizona Tucson AZ 85721-0043 USA Department of Soils Water and Environmental Science The University of Arizona Tucson AZ 85721-0038 USA

For more than a decade, the Four Comers Region has faced extensive and persistent drought conditions that have impacted vegetation communities and local water resources while exacerbating soil erosion. These persistent droughts threaten ecosystem services, agriculture, and livestock activities, and expose the hypersensitivity of this region to inter-annual climate variability and change. Much of the intermountain Western United States has sparse climate and vegetation monitoring stations, making fine-scale drought assessments difficult. Remote sensing data offers the opportunity to assess the impacts of the recent droughts on vegetation productivity across these areas. Here, we propose a drought assessment approach that integrates climate and topographical data with remote sensing vegetation index time series. Multisensor Normalized Difference Vegetation Index （NDVI） time series data from 1989 to 2010 at 5.6 km were analyzed to characterize the vegetation productivity changes and responses to the ongoing drought. A multi-linear regression was applied to metrics of vegetation productivity derived from the NDVI time series to detect vegetation productivity, an ecosystem service proxy, and changes. The results show that around 60.13% of the study area is observing a general decline of greenness （p 〈 0.05）, while 3.87% show an unexpected green up, with the remaining areas showing no consistent change. Vegetation in the area show a significant positive correlation with elevation and precipitation gradients. These results, while, confirming the region＇s vegetation decline due to drought, shed further light on the future directions and challenges to the region＇s already stressed ecosystems. Whereas the results provide additional insights into this isolated and vulnerable region, the drought assessment approach used in this study may be adapted for application in other regions where surfacebased climate and vegetation monitoring record is spatially and temporally limited.

关键词： drought remote sensing Hopi Navajo Nation

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First Insights into the Viral Communities of the Deep-sea Anoxic Brines of the Red Sea

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Genomics, Proteomics & Bioinformatics 2015年第5期13卷 304-309页

作者： Andr Antunes Intikhab Alam Marta Filipa Simoes Camille Dan.els Ari j.S.Ferreira Rania Siam Hamza el-Dorry Vladimir B.Bajic Computational Bioscience Research Center (CBRC) ComputerElectrical and Mathematical Sciences and Engineering Division (CEMSE)King Abdullah University of Science and Technology (KAUST) Red Sea Research Center (RSRC) Biological and Environmental Sciences and Engineering Division (BESE)King Abdullah University of Science and Technology (KAUST) Biology Department American University in Cairo

The deep-sea brines of the Red Sea include some of the most extreme and unique envi- ronments on Earth. They combine high salinities with increases in temperature, heavy metals, hydrostatic pressure, and anoxic conditions, creating unique settings for thriving populations of novel extremophiles. Despite a recent increase of studies focusing on these unusual biotopes, their viral communities remain unexplored. The current survey explores four metagenomic datasets obtained from different brine-seawater interface samples, focusing specifically on the diversity of their viral communities. Data analysis confirmed that the particle-attached viral communities present in the brine-seawater interfaces were diverse and generally dominated by Candovirales, yet appearing distinct from sample to sample. With a level of caution, we report the unexpected finding of Phycodnaviridae, which infects algae and plants, and trace amounts of insect-infecting Iridoviridae. Results from Kebrit Deep revealed stratification in the viral communities present in the interface： the upper-interface was enriched with viruses associated with typical marine bacteria, while the lower-interface was enriched with haloviruses and halophages. These results provide first insights into the unexplored viral communities present in deep-sea brines of the Red Sea, represent- ing one of the first steps for ongoing and future sampling efforts and studies.

关键词： Viral diversity Metagenomics Brine-seawater interface Caudovirales Red Sea

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Asian journal of Andrology 2008年第2期10卷 177-187页

作者： Khaled Hamden Dorothee Silandre Christelle Delalande Abdefattah el Feki Serge Carreau Animal Ecophysiology Faculty of Sciences Sfax-3018 Tunisia USC 20061NRA- EA 2608 Biochemistry Caen-14032 France

Aim： To examine the effects on rat aging of caloric restriction （CR1） and undernutrition （CR2） on the body and on testicular weights, on two enzymatic antioxidants （superoxide dismutase and catalase）, on lipid peroxidation and on the expression of testicular aromatase and estrogen receptors （ER）. Methods： CR was initiated in 1-month-old rats and carried on until the age of 18 months. Results： In control and CR2 rats an age-related decrease of the aromatase and of ER （α and β） gene expression was observed; in parallel a diminution of testicular weights, and of the total number and motility of epididymal spermatozo was recorded. In addition, aging in control and CR2 rats was accompartied by a significant decrease in testicular superoxide dismutase, catalase activities, and an increase in lipid peroxidation level （thiobarbituric acid reactive substance）, associated with alterations of spermatogenesis. Conversely, caloric restriction-treatment exerted a protective effect and all the parameters were less affected by aging. Conclusion： These results indicate that during aging, a low caloric diet （not undernutrition） is beneficial for spermatogenesis and likely improves the protection of the cells via an increase of the cellular antioxidant defense system in which aromatase/ ER could play a role. （Asian j Andro12008 Mar; 10： 177-187）

关键词： aging low caloric diet rat testis aromatase estrogen receptors antioxidants

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Indium doping effect on properties of ZnO nanoparticles synthesized by sol–gel method

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Chinese Physics B 2019年第4期28卷 342-348页

作者： S Mourad j el Ghoul K Omri K Khirouni Laboratory of Physics of Materials and Nanomaterials Applied at Environment (LaPhyMNE) Faculty of Sciences in Gabes Gabes University Imam Mohammad Ibn Saud Islamic University (IMSIU) College of Sciences Department of Physics

Pure ZnO and indium-doped ZnO(In–ZO) nanoparticles with concentrations of In ranging from 0 to 5% are synthesized by a sol–gel processing technique. The structural and optical properties of ZnO and In–ZO nanoparticles are characterized by different techniques. The structural study confirms the presence of hexagonal wurtzite phase and indicates the incorporation of In^(3+) ions at the Zn^(2+) sites. However, the optical study shows a high absorption in the UV range and an important reflectance in the visible range. The optical band gap of In–ZnO sample varies between 3.16 e V and 3.22 e V. The photoluminescence(PL) analysis reveals that two emission peaks appear: one is located at 381 nm corresponding to the near-band-edge(NBE) and the other is observed in the green region. The aim of this work is to study the effect of indium doping on the structural, morphological, and optical properties of ZnO nanoparticles.

关键词： In-doped ZnO nanoparticles sol–gel process structural and optical characterization

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Enhanced photocatalytic activities of silicon nanowires/graphene oxide nanocomposite:Effect of etching parameters

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journal of Environmental Sciences 2021年第3期33卷 123-134页

作者： Mounir Gaidi Kais Daoudi Soumya Columbus Anouar Hajjaji My Ali el Khakani Brahim Bessais Department of Applied Physics and Astronomy University of SharjahSharjah 27272United Arab Emirates Sharjah Centre for Advanced Materials Research Research Institute of Sciences and EngineeringUniversity of SharjahSharjah 27272United Arab Emirates Sharjah Sharjah Research Academy University CitySharjah 60999United Arab Emirates Sharjah Laboratoire de Photovoltaïque Centre de Recherches et des Technologies de l’EnergieTechnopole de Borj-CédriaHammam-Lif 2050Tunisia Institut National de la Recherche Scientifique(INRS) INRS-ÉnergieMatériaux et Télécommunications1650Blvd.Lionel-BouletVarennesQC J3X-1S2Canada

Homogeneous and vertically aligned silicon nanowires(SiNWs)were successfully fabricated using silver assisted chemical etching *** prepared samples were characterized using scanning electron microscopy,transmission electron microscopy and atomic force *** degradation properties of graphene oxide(GO)modified SiNWs have been *** found that the SiNWs morphology depends on etching time and etchant *** SiNWs length could be tuned from 1 to 42μm,respectively when varying the etching time from 5 to 30 *** etchant concentration was found to accelerate the etching process;doubling the concentrations increases the length of the SiNWs by a factor of two for fixed etching *** in bundle morphology were also studied as function of etching *** SiNWs diameter was found to be independent of etching time or etchant composition while the size of the SiNWs bundle increases with increasing etching time and etchant *** addition of GO was found to improve significantly the photocatalytic activity of SiNWs.A strong correlation between etching parameters and photocatalysis efficiency has been observed,mainly for SiNWs prepared at optimum etching time and etchant concentrations of 10 min and 4:1:8.A degradation of92%was obtained which further improved to 96%by addition of hydrogen *** degradation efficiency of 16%and 31%has been observed for bare Si and GO/bare Si samples *** obtained results demonstrate that the developed SiNWs/GO composite exhibits excellent photocatalytic performance and could be used as potential platform for the degradation of organic pollutants.

关键词： Photocatalysis Nanomaterials Methylene Blue Silicon nanowire Graphene oxide Water treatment

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Design and validation of a handheld capnography device for cardiopulmonary assessment based on the Arduino platform

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journal of Innovative Optical Health Sciences 2021年第6期4卷 42-54页

作者： Om Prakash Singh Ismail M.el-Badawy M.B.Malarvili Bio-signal Processing Research Group(BSPRG)School of Biosciences and Medical Engineering Universiti Teknologi Malaysia(UTM) 81310 SkudaiJohorMalaysia electronics and Communication Engineering Department Arab Academy for Science and Technology CairoEgypt School of Electrical Engineering Universiti Teknologi Malaysia(UTM)81310 SkudaiJohorMalaysia Bio-Signal Processing Research Group(BSPRG)School of Biosciences and Medical Engineering Universiti Teknologi Malaysia(UTM) 81310 SkudaiJohorMalaysia

The design of a handheld capnography device is in great demand because of its effective and practical uses in all cardiac arrest resuscitations,according to the recommendation of the American Heart ***,a handheld capnography device that can be used in clinical settings and the home environment is *** proposed device was developed by using an infrared CO_(2)sensor,Arduino Mega2560,and a high-resolution display(2.8").Furthermore,two rechargeable batteries(7.6 V,0.99 A)and a secure digital card with a capacity of 16 GB were incorporated to increase the portability and usability of the *** were implemented to measure standard features,namely,inspired CO_(2)(ICO_(2)),end-tidal CO_(2)(EtCO_(2)),and re-spiratory rate(RR).The features of 15 healthy subjects were recorded by using the developed prototype and the standard capnography device(Capnostream^(TM)20 Model CS08798).Validation was performed with Bland-Altman *** revealed that mean differences±standard deviations for the set limits of ICO_(2),EtCO_(2)and RR were 0.29±1.30 millimeters of mercury(mmHg),0.15±1.77 mmHg and 0.40±0.97 breaths per minute(bpm),*** of the differences among device measurements across all features fell within the 95%limits of ***,the developed device may help manage respiratory distress conditions in and outside of a hospital setting.

关键词： Arduino board capnogram carbon dioxide sensor cardiorespiratory monitoring system

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Assessment of the Protective Capacity of Vadoze Zone over Aquifer Systems Using Secondary Geoelectrical Parameters: A Case Study of Kaltungo Area North East, Nigeria

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journal of Environmental & Earth Sciences 2020年第2期2卷 1-11页

作者： E.Y.Mbiimbe I.B.Goni j.M.el-Nafaty A.U.Yuguda Department of Geology Gombe State University Department of Geology University of Maiduguri

An assessment of the protective capacity of the vadose zone overlyingthe aquifer systems in the Kaltungo area was carried out to determine itsinfluence on groundwater quality. Applying the schlumberger array with amaximum electrode spread AB/2 = 100m through VES, thirty water wellpoints were surveyed using Omega terrameter (PIOSO1) resistivity *** field data was first subjected to manual interpretation through curvemarching and then digitized modeled curves using computer software. Theinterpreted data revealed that the area is characterized by eleven differentcurve types representing three to five geo electrical layers. In order toassess the protective capacity of the vadoze zone over the aquifer systems,the longitudinal conductance (S) and transverse resistance (T) (secondarygeoelectric parameters) were computed from the primary data using theDar Zarouk formula. The values of S obtained range from 0.0018 to 0.4056ohms with a mean value of 0.0135 ohms while the values of T range from0.55 ohms to 1195.68 ohms with a mean value of 39.84 ohms. The valuesof S and T obtained reveal that 90% of probed points has poor protectivecapacity, 10 % has moderate protective capacity and 83 % has hightransmissivity, 17 % has intermediate transmissivity. The T and S values areskewed towards poorly protective capacity thus making groundwater in thearea highly vulnerable to contamination from the surface. To achieve goodgroundwater quality in the area, proper completion of newly constructedwells should install protective casing through the entire vadose zone.

关键词： Assessment Protective Capacity Vadose zone Aquifer systems Secondary Geoelectric Parameters and Kaltungo Area

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Comparative Analysis of Climatic Change Trend and Change-Point Analysis for Long-Term Daily Rainfall Annual Maximum Time Series Data in Four Gauging Stations in Niger Delta

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Open journal of Modern Hydrology 2023年第4期13卷 229-245页

作者： Masi G. Sam Ify L. Nwaogazie Chiedozie Ikebude jonathan O. Irokwe Diaa W. el Hourani Ubong j. Inyang Bright Worlu Department of Civil and Environmental Engineering University of Port Harcourt Port Harcourt Nigeria Center for Occupational Health Safety and Environment University of Port Harcourt Port Harcourt Nigeria

The aim of this study is to establish the prevailing conditions of changing climatic trends and change point dates in four selected meteorological stations of Uyo, Benin, Port Harcourt, and Warri in the Niger Delta region of Nigeria. Using daily or 24-hourly annual maximum series (AMS) data with the Indian Meteorological Department (IMD) and the modified Chowdury Indian Meteorological Department (MCIMD) models were adopted to downscale the time series data. Mann-Kendall (MK) trend and Sen’s Slope Estimator (SSE) test showed a statistically significant trend for Uyo and Benin, while Port Harcourt and Warri showed mild trends. The Sen’s Slope magnitude and variation rate were 21.6, 10.8, 6.00 and 4.4 mm/decade, respectively. The trend change-point analysis showed the initial rainfall change-point dates as 2002, 2005, 1988, and 2000 for Uyo, Benin, Port Harcourt, and Warri, respectively. These prove positive changing climatic conditions for rainfall in the study area. Erosion and flood control facilities analysis and design in the Niger Delta will require the application of Non-stationary IDF modelling.

关键词： Rainfall Time Series Data Climate Change Trend Analysis Variation Rate Change Point Dates Non-Parametric Statistical Test

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Effect of Heat Input on the Microstructure and Properties of Dissimilar Weld joint Between Incoloy 28 and Superaustenitic Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2014年第2期27卷 259-266页

作者： M.S.Abdel Rahman N.A.Abdel Raheem M.R.el Koussy Department of Metallurgy Faculty of EngineeringCairo University

Abstract This work focuses on studying the effect of welding heat input within the range from 1 to 5 kj/mm on the microstructure and the corresponding mechanical and corrosion properties of dissimilar joint between superaustenitic stainless steel （UNS S31254） and Incoloy 28 （UNS N08028）. The two materials were butt-welded with ER NiCrMo3. The metallurgical changes associated with welding of SASS and Incoloy 28 were studied using optical microscope, SEM, and EDX. The mechanical and corrosion properties were investigated using tensile test, Vickers hardness test, and pitting and crevice corrosion tests. The weld metal microstructure showed precipitates with needle-like shape at 3 and 5 kj/mm. Also, the microstructure showed unmixed zone （UMZ） at the fusion line of both SASS and Incoloy 28 sides at all the investigated heat inputs. The Mo microsegregation within UMZ at Incoloy 28 side increased as the heat input increased from 1 to 5 k j/ram but that in SASS increased with increasing heat input from 1 to 3 kj/mm and then decreased with increasing from 3 to 5 kj/mm. The ultimate tensile strengths for all specimens at all the investigated heat inputs are acceptable. The average hardness noticeably changed in weld metal as the heat input increased from 1 to 5 kj/mm. Other zones such as HAZ or UMZ did not demonstrate marked changes in the average hardness. The pitting and crevice corrosion rates of the weld joint were found significant at l and 3 kj/mm but insignificant at 5 kj/mm according to ASTM G48.

关键词： Superaustenitic Incoloy 28 Welding Heat input Unmixed zone Microsegregation Corrosion

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SATB2:A versatile transcriptional regulator of craniofacial and skeleton development,neurogenesis and tumorigenesis,and its applications in regenerative medicine

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Genes & Diseases 2022年第1期9卷 95-107,I0005页

作者： Xia Huang Qiuman Chen Wenping Luo Mikhail Pakvasa Yuxin Zhang Liwen Zheng Shuang Li Zhuohui Yang Huan Zeng Fang Liang Fugui Zhang Dan.el A.Hu Kevin H.Qin Eric j.Wang David S.Qin Russell R.Reid Tong-Chuan He Aravind Athiviraham Mostafa el Dafrawy Hongmei Zhang Stomatological Hospital of Chongqing Medical University Chongqing 401147PR China Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences Chongqing 401147PR China Molecular Oncology Laboratory Department of Orthopaedic Surgery and Rehabilitation MedicineThe University of Chicago Medical CenterChicagoIL 60637USA The Pritzker School of Medicine The University of Chicago Medical CenterChicagoIL 60637USA Department of Surgery The University of Chicago Medical CenterChicagoIL 60637USA Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education Chongqing 401147PR China

SATB2(special AT-rich sequence-binding protein 2)is a member of the special AT-rich binding protein *** a transcription regulator,SATB2 mainly integrates higher-order chromatin ***2 expression appears to be tissue-and stage-specific,and is governed by several cellular signaling molecules and *** in branchial arches and osteoblast-lineage cells,SATB2 plays a significant role in craniofacial pattern and skeleton *** addition to regulating osteogenic differentiation,SATB2 also displays versatile functions in neural development and cancer *** an osteoinductive factor,SATB2 holds great promise in improving bone regeneration toward bone defect *** this review,we have summarized our current understanding of the physiological and pathological functions of SATB2 in craniofacial and skeleton development,neurogenesis,tumorigenesis and regenerative medicine.

关键词： Bone regeneration Development Neurogenesis SATB2 Tumorigenesis

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