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Dielectric Resonator Magnetoelectric Dipole Arrays with Low Cross Polarization,Backward Radiation,and Mutual Coupling for MIMO Base Station Applications

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China Communications 2024年第6期21卷 290-304页

作者： Song Simin da Yiran Qian Bingyi Huang Xiaoyu Chen Xiaoming Li Yingsong ahmed A.Kishk School of Information and Communications Engineering Xi’an Jiaotong UniversityXi’an 710049China Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education Anhui UniversityHefei 230039China Department of Electrical and Computer Engineering Concordia UniversityMontrealQC H3G 1M8Canada

Dielectric resonator magnetoelectric dipole(DRMED)arrays with enhanced isolation,reduced cross-polarization,and backward radiation are proposed for base station(BS)*** proposed antenna comprises an elevated dielectric resonator antenna(DRA)on a small metal plate above a sizeable common ground *** DRA is designed in its T Eδ11 mode,acting like a magnetic *** surface current excited by the differential probes flowing on the small ground plane is equivalent to an electric *** these two equivalent dipoles are orthogonal,they have the magnetoelectric dipole characteristics with reduced backward ***,the small ground planes can be treated as decoupling structures to provide a neutralization path to cancel the original coupling path.A linearly-polarized 4-element prototype array was verified experimentally in previous ***,a dual-polarized DRMED antenna is presented to construct a 2-element and 4×4 array for BS *** investigate its MIMO performance,sophisticated multi-cell scenario simulations are carried *** using the proposed dualpolarized DRMED array,the cellular system capacityis improved by 118.6%compared to a conventional DRA *** significant MIMO system improvement is mainly due to the reduced backward radiation and,therefore,reduced inter-cell *** align well with the simulations.

关键词： backward radiation dielectric resonator antennas(DRAs) isolation magnetoelectric-dipole(ME-dipole)antennas

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Prevalence and Factors Associated with Chronic Low Back Pain in the Mining Sector in Burkina Faso

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Occupational Diseases and Environmental Medicine 2024年第3期12卷 211-224页

作者： Marthe Sandrine Sanon Lompo Gaston Kaboré Jules Owona Manga Issa Traoré Ibrahim Mama Cissé Marius Kédoté ahmed Kaboré Nicolas Méda Dpartement de Sant Publique Unit de Formation et de Recherche en Sciences de la Sant Universit Joseph Ki Zerbo Ouagadougou Burkina Faso Centre Hospitalier Universitaire Yalgado Oudraogo Ouagadougou Burkina Faso Facult des Sciences de la Sant Universit de Yaound Yaound Camroun Institut Suprieur des Sciences de la Sant Universit Nazi BONI Bobo Dioulasso Burkina Faso Facult de Mdecine Universit de Parakou Parakou Bnin Centre Rgional de Formation en Sant Publique Ouidah Benin

Introduction: Low back pain is nowadays a real public health problem in companies. The objective of the study was to determine the prevalence and factors associated with chronic low back pain among workers of a mining company in Burkina Faso. Material and Methods: This was a descriptive and analytical cross-sectional study with a retrospective collection that took place from August 1, 2021 to March 16, 2022 in a gold mine in Burkina Faso. It focused on mine workers who participated in the 2019 annual medical visit. Results: Out of a total workforce of 880 workers who took part in the annual medical visit in 2019, 165 had chronic common low back pain, i.e. a prevalence of 18.75%. The average age of low back pain workers was 37.21 ± 7.5 years. Among the workers suffering from low back pain, 62 (37.58%) held the position of machine operator. Clinically, mechanical pain was found in 113 low back pain workers (76%) and twenty-nine (17.58%) had radicular pain. Standard radiography of the lumbar spine was abnormal in 129 workers (78.18%. In the univariate analysis, the factors associated with the pathology were sex, level of study, work station and seniority in the position. After a logistic regression, the factors associated with its occurrence were whole-body vibration (Fisher’s test = 12.7541;P = 0.000), male sex (Fisher’s test = 8.363;P = 0.004), and seniority for 4 to 5 years (Chi2 = 4.0234;p = 0.046). Conclusion: The study reveals the existence of chronic low back pain cases among the workers of the mining company. There is a predominance of the pathology in men, workers exposed to vibrations and those with a seniority of 4 to 5 years. It is necessary to establish a policy of prevention of low back pain for the benefit of workers, in particular those exposed to vibrations.

关键词： Chronic Low Back Pain Prevalence Associated Factors Mine Burkina Faso

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The linkage between Bitcoin and foreign exchanges in developed and emerging markets

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Financial Innovation 2023年第1期9卷 1003-1029页

作者： ahmed BenSaïda LaREMFiQ Laboratory University of SousseSousseTunisia College of Business Effat UniversityJeddahSaudi Arabia

This study investigates the connectedness between Bitcoin and fiat currencies in two groups of countries:the developed G7 and the emerging *** methodology adopts the regular(R)-vine copula and compares it with two benchmark models:the multivariate t copula and the dynamic conditional correlation(DCC)GARCH ***,this study examines whether the Bitcoin meltdown of 2013,selloff of 2018,COVID-19 pandemic,2021 crash,and the Russia-Ukraine conflict impact the linkage with conventional *** results indicate that for both currency baskets,R-vine beats the benchmark ***,the dependence is better modeled by providing sufficient information on the shock transmission ***,the cross-market linkage slightly increases during the Bitcoin crashes,and reaches significant levels during the 2021 and 2022 crises,which may indicate the end of market isolation of the virtual currency.

关键词： Cryptocurrency Fiat currency Bitcoin crashes Market integration

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Antihyperglycemic effect of methanol extract of Tamarix aphylla L. Karst (Saltcedar) in streptozocin–nicotinamide induced diabetic rats

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Asian Pacific Journal of Tropical Biomedicine 2017年第7期7卷 619-623页

作者： rooh ullah shafiq ahmed tariq naeem khan nawaz sharif zia ud din khalid mansoor department of pharmacology institute of basic medical sciences khyber medical university

Objective: To evaluate the antihyperglycemic potential of Tamarix aphylla(T. aphylla)leaves in STZ–NIC induced diabetes in Wister Albino ***: Acute toxicity study was done to check the toxicity of T. aphylla(L. Karst)methanol extract. T. aphylla leaves extract was administered intraperitoneally(100 mg,250 mg and 400 mg/kg body weight per day) to diabetic Wister rats for 21 days. The various parameters were studied including fasting blood glucose levels, haemoglobin and glycosylated ***: The treatment groups with the extract at three dose levels expressively abridged the intensities of blood glucose and Glycosylated Haemoglobin. The earlier detected reduced level of plasma haemoglobin of the diabetic rats was raised to near normalcy with treatment of ***: The results of the current study confirm that the leaves extract of T. aphylla are nontoxic and have antidiabetic nature.

关键词： Tamarix aphylla leaves Diabetes Streptozotocin Antidiabetic potential Insulin secretion

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Origin of Quartz Cement in the Paleogene Sandstone Reservoir of Shahejie Formation,Bohai Bay Basin,China

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Acta Geologica Sinica(English Edition) 2022年第1期96卷 248-260页

作者： Muhammad KASHIF CAO Yingchang Nizam ud DIN Uzair SIDDIQUE XI Kelai Faisal REHMAN Noor ahmed GU Xihao Mohammad Saleh GAGHMAN Department of Earth sciences University of SargodhaSargodha 40100Pakistan School of Geosciences China University of PetroleumQingdaoShandong 266580China College of Earth sciences and Engineering Hohai UniversityNanjing 210098China Institute of Marine Geology and Resources Ocean CollegeZhejiang UniversityZhoushanZhejiang 316021China Department of Earth sciences Quaid-I-Azam UniversityIslamabad 45320Pakistan

The precipitation of authigenic quartz plays a significant role to reduce the reservoir characteristics and enhance the stiffness of the *** Es_(1) sandstone of Shahejie Formation is acting as a significant hydrocarbon producing rock in the Nanpu *** methods like thin section petrography,cathodoluminescence(CL),scanning electron microscope(SEM,with EDS),and electron microprobe analysis has been used to reveal the origin of quartz cement as well as to evaluate the effect of quartz cement on reservoir *** studied sandstone is classified as immature to mature feldspathic litharenite and lithic arkose and consists of quartz,feldspar,rock fragments and *** studies and SEM analysis shows that the authigenic quartz is acting a significant cement that reduces the reservoir *** clay minerals(kaolinite and mixed layer illite to smectite)are dominant in the Es_(1) sandstone,that can reduce the reservoir ***,CL and thin section analysis reveal that there are two stages of quartz cement in the studied samples;that are pore filling authigenic cement and quartz overgrowth *** inclusion homogenization temperatures shows that stages of quartz cement were developed with continuous process from 70℃ to 130℃.Quartz cements were generally originated from I/S reaction,feldspar dissolution,conversion of rock fragments and pressure *** dissolution(K-feldspar)and kaolinite to illite reaction is an insignificant silica source for the silica cement which is internally precipitated in a close system with diffusion transporting ***,quartz cement significantly enhance the rock strengthen and brittleness effectively as well as it reduce the overall reservoir quality.

关键词： origin authigenic quartz silica sources diffusion Shahejie Formation

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Toxicity assessment of polyethylene microplastics in combination with a mix of emerging pollutants on Physalaemus cuvieri tadpoles

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Journal of Environmental Sciences 2023年第5期127卷 465-482页

作者： Amanda Pereira da Costa Araújo Thiarlen Marinho da Luz Mohamed ahmed Ibrahim ahmed Mir Mohammad Ali Md.Mostafizur Rahman Bojan Nataraj daniela de Melo e Silva damiàBarceló Guilherme Malafaia Post-Graduation Program in Environmental Sciences Federal University of GoiásGoianiaGO 74690-970Brazil Laboratory of Toxicology Applied to the Environment Goiano Federal InstituteUrutaíGO 75790-000Brazil Plant Protection Department Faculty of AgricultureAssiut UniversityAssiut 71526Egypt Department of Aquaculture Faculty of FisheriesAquaculture&Marine ScienceSher-e-Bangla Agricultural UniversityDhaka 1207Bangladesh Department of Environmental Sciences Jahangirnagar UniversitySavar 1342Bangladesh Unit of Toxicology Department of ZoologySchool of Life SciencesBharathiar UniversityCoimbatore 641046India Laboratory of Environmental Mutagenesis Federal University of GoiásGoianiaGO 74690-970Brazil Catalan Institute for Water Research(ICRA-CERCA) H_(2)O BuildingScientific and Technological Park of the University of GironaEmili Grahit 101Girona 17003Spain Water and Soil Quality Research Group Department of Environmental ChemistryInstitute of Environmental Assessment and Water Research(IDAEA-CSIC)JordiGirona 1826Barcelona 08034Spain Post-Graduation Program in Conservation of Cerrado Natural Resources Goiano Federal InstituteUrutaíGO 75790-000Brazil Post-Graduation Program in Ecology Conservationand BiodiversityFederal University of UberlandiaUberlandiaMG 38400-902Brazil Post-Graduation Programa in Biotechnology and Biodiversity Federal University of GoiásGoianiaGO 74605-050Brazil

Studies in recent years have shown that aquatic pollution by microplastics(MPs)can be considered to pose additional stress to amphibian ***,our knowledge of how MPs affect amphibians is very rudimentary,and even more limited is our understanding of their effects in combination with other emerging ***,we aimed to evaluate the possible toxicity of polyethylene MPs(PE-MPs)(alone or in combination with a mix of pollutants)on the health of Physalaemus cuvieri *** 30 days of exposure,multiple biomarkers were measured,including morphological,biometric,and developmental indices,behavioral parameters,mutagenicity,cytotoxicity,antioxidant and cholinesterase responses,as well as the uptake and accumulation of PE-MPs in *** on the results,there was no significant change in any of the parameters measured in tadpoles exposed to treatments,but induced stress was observed in tadpoles exposed to PE-MPs combined with themixture of pollutants,reflecting significant changes in physiological and biochemical *** principal component analysis(PCA)and integrated biomarker response(IBR)assessment,effects induced by pollutants in each test group were distinguished,confirming that the exposure of *** tadpoles to the PE-MPs in combination with a mix of emerging pollutants induces an enhanced stress response,although the uptake and accumulation of PE-MPs in these animalswas ***,our study provides newinsight into the danger to amphibians of MPs coexisting with other pollutants in aquatic environments.

关键词： Amphibians Environmental toxicology Micropollutants Emerging pollutants Aquatic pollution Biomarkers

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Detailed investigation of optimized alkali catalyzed transesterification of Jatropha oil for biodiesel production

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Journal of Energy Chemistry 2015年第3期24卷 331-336页

作者： Waqas ahmed Muhammad Faizan Nazar Syed danish Ali Usman Ali Rana Salah ud-Din Khan National Centre for Physics Quaid-i-Azam University Campus Office of Research Innovation and CommercializationUniversity of Gujrat Department of Chemistry University of Gujrat Sustainable Energy Technologies (SET) Center College of EngineeringPO-Box 800King Saud University

The non-edible oils are believed to be one of the major feedstock for the production of biodiesel in *** the present study,we investigated the production of Jatropha oil methyl esters（JOMEs） via alkali-catalyzed transesterification *** biophysical characteristics of Jatropha oil were found within the optimal range in accordance with ASTM standards as a substitute diesel *** chemical composition and production yield of as-synthesized biodiesel were confirmed by various analytical techniques such as FT-IR,1H NMR,13 C NMR and gas chromatography coupled with mass spectrometry.A high percentage conversion,～96.09%,of fatty acids into esters was achieved under optimized transesterification conditions with 6 ：1 oil to methanol ratio and 0.9 wt% Na OH for 50 min at ～60°***,twelve fatty acids methyl esters（FAME） were quantified in the GC/MS analysis and it was interesting to note that the mass fragmentation pattern of saturated,monounsaturated and diunsaturated FAME was comparable with the literature reported values.

关键词： Jatropha oil methyl esters transesterification biodiesel fuel gas chromatography mass spectrometry

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Use of Random Amplified Polymorphic DNA Analysis for Economically Important Food Crops

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Journal of Integrative Plant Biology 2007年第12期49卷 1670-1680页

作者： Halima Hassan Salem Bahy ahmed Ali Tian-Hua Huang da-Nian Qin Xiao-Mei Wang Qing-Dong Xie Cell Biology and Medical Genetics Department Medical College Shantou University Shantou 515031 Nucleic Acid Research Department Genetic Engineering and Biotechnology Research InstituteMubarak City for Scientific Research & Technology Applications New Borg El-Arab City 21934 Alexandria Egypt Physiology Department Medical College Shantou University Shantou 515031 China Department of Biochemistry and Molecular Biology Life Science School Shenzhen University Shenzhen 518060 China

The objective of this review is to summarize numerous studies on the use of the random amplified polymorphic DNA （RAPD） technique on rice, corn, wheat, sorghum, barley, rye, and oats to examine its feasibility and validity for assessment of genetic variation, population genetics, mapping, linkage and marker assisted selection, phylogenetic analysis, and the detection of somaclonal variation. Also we discuss the advantages and limitations of RAPD. Molecular markers have entered the scene of genetic improvement in different fields of agricultural research. The simplicity of the RAPD technique made it ideal for genetic mapping, plant and animal breeding programs, and DNA fingerprinting, with particular utility in the field of population genetics.

关键词： random amplified polymorphic DNA food crops poaceae.

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Novel mutations in PDE6A and CDHR1 cause retinitis pigmentosa in Pakistani families

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International Journal of Ophthalmology(English edition) 2021年第12期14卷 1843-1851页

作者： Muhammad dawood Siying Lin Taj ud Din Irfan Ullah Shah Niamat Khan Abid Jan Muhammad Marwan Komal Sultan Maha Nowshid Raheel Tahir Asif Naveed ahmed Muhammad Yasin Emma LBaple Andrew HCrosby Shamim Saleha Department of Biotechnology and Genetic Engineering Kohat University of Science and Technology(KUST)Kohat 26000Khyber PakhtunkhwaPakistan Medical Research RILD Wellcome Wolfson Centre(Level 4)Royal Devon and Exeter NHS Foundation TrustExeterDevon EX25DWUK Department of Ophthalmology KMU Institute of Medical Sciences(KIMS)Kohat 26000Khyber PakhtunkhwaPakistan

AIM:To investigate the genetic basis of autosomal recessive retinitis pigmentosa(arRP)in two consanguineous/endogamous Pakistani ***:Whole exome sequencing(WES)was performed on genomic DNA samples of patients with arRP to identify disease causing *** sequencing was performed to confirm familial segregation of identified mutations,and potential pathogenicity was determined by predictions of the mutations’***:A novel homozygous frameshift mutation[NM_000440.2:c.1054delG,p.(Gln352Argfs*4);Chr5:g.149286886del(GRCh37)]in the PDE6A gene in an endogamous family and a novel homozygous splice site mutation[NM_033100.3:c.1168-1G>A,Chr10:g.85968484G>A(GRCh37)]in the CDHR1 gene in a consanguineous family were *** PDE6A variant p.(Gln352Argfs*4)was predicted to be deleterious or pathogenic,whilst the CDHR1 variant c.1168-1G>A was predicted to result in potential alteration of ***:This study expands the spectrum of genetic variants for arRP in Pakistani families.

关键词： autosomal recessive retinitis pigmentosa PDE6A CDHR1 variants Pakistani families

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Analysis of Bifenthrin Degrading Bacteria from Rhizosphere of Plants Growing at Tannery Solid Waste

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American Journal of Plant Sciences 2015年第13期6卷 2042-2050页

作者： Mukhtar ahmed Farkhanda Jabeen Muhammad Ali Zarnab Ahmad Fayyaz ahmed Muhammad Bilal Sarwar Salah ud Din Mubbashir Hassan Shah Jahan Centre of Excellence in Molecular Biology University of the Punjab Lahore Pakistan Department of Botany University of the Punjab Lahore Pakistan

Bifenthrin is an insecticide which is used to control insects, mites, and ticks. It poses a solemn en-vironmental threat and health risk to living organisms. It may be bioaccumulated or biomagnified at different trophic levels in the food chain by biota. Microbes are hidden creature of earth’s biodiversity. For isolation of bifenthrin degrading bacteria, rhizospheric soil samples of plants like Pisum sativum, Triticun aestvum, Chenopodium album were taken from tannery solid waste, Kasur, Pakistan. Enrichment culture techniques were used for the isolation of bacterial strains that showed luxurious growth on minimal growth media with bifenthrin dose was selected for biodegradation study. Bacteria were further screened out based on their morphological, biochemical parameters and degradation efficiency. Furthermore the effect of different growth factors like temperature, pH, inoculum concencentration, minimal inhibitory concentration of heavy metals and antibiotics were also studied. Bacterial strains of Xanthomonas and Bacillus sp. were identified as efficient degrading microbes. Maximum bifenthrin utilization were observed at 25°C (pH 7), with 500 μL inoculum of Bacillus sp., while Xanthomonas sp. gave optimm utilization at 30°C (pH 7) at the same inoculum volume of bacteria. The Rf values of Bacillus sp. and Xanthomonas sp. were 0.91 and 0.90 respectively, which indicated their potential to metabolize bifenthrin into nontoxic forms. These strains can be used to clean up the sites polluted with pesticides and tannery wastes when present in rhizosphere of plants.

关键词： Bifenthrin Biodegradation Tannery Solid Waste Rhizosphere

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