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Mechanism of Thermally Radiative Prandtl Nanofluids and Double-Diffusive Convection in Tapered Channel on Peristaltic Flow with Viscous Dissipation and Induced Magnetic Field
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作者 Yasir Khan Safia Akram +3 位作者 Maria Athar Khalid Saeed Alia Razia A.Alameer 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1501-1520,共20页
The application of mathematical modeling to biological fluids is of utmost importance, as it has diverse applicationsin medicine. The peristaltic mechanism plays a crucial role in understanding numerous biological flo... The application of mathematical modeling to biological fluids is of utmost importance, as it has diverse applicationsin medicine. The peristaltic mechanism plays a crucial role in understanding numerous biological flows. In thispaper, we present a theoretical investigation of the double diffusion convection in the peristaltic transport of aPrandtl nanofluid through an asymmetric tapered channel under the combined action of thermal radiation andan induced magnetic field. The equations for the current flow scenario are developed, incorporating relevantassumptions, and considering the effect of viscous dissipation. The impact of thermal radiation and doublediffusion on public health is of particular interest. For instance, infrared radiation techniques have been used totreat various skin-related diseases and can also be employed as a measure of thermotherapy for some bones toenhance blood circulation, with radiation increasing blood flow by approximately 80%. To solve the governingequations, we employ a numerical method with the aid of symbolic software such as Mathematica and MATLAB.The velocity, magnetic force function, pressure rise, temperature, solute (species) concentration, and nanoparticlevolume fraction profiles are analytically derived and graphically displayed. The results outcomes are compared withthe findings of limiting situations for verification. 展开更多
关键词 Double diffusion convection thermal radiation induced magnetic field peristaltic flow tapered asymmetric channel viscous dissipation Prandtl nanofluid
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Crashworthiness Design and Multi-Objective Optimization of Bionic Thin-Walled Hybrid Tube Structures
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作者 Pingfan Li Jiumei Xiao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期999-1016,共18页
Thin-walled structures are widely used in cars due to their lightweight construction and energy-absorbing properties.However,issues such as high initial stress and lowenergy-absorbing efficiency arise.This study propo... Thin-walled structures are widely used in cars due to their lightweight construction and energy-absorbing properties.However,issues such as high initial stress and lowenergy-absorbing efficiency arise.This study proposes a novel energy-absorbing structure inwhich a straight tube is combinedwith a conical tube and a bamboo-inspired bulkhead structure is introduced.This configuration allows the conical tube to flip outward first and then fold together with the straight tube.This deformation mode absorbs more energy and less peak force than the conical tube sinking and flipping inward.Through finite element numerical simulation,the specific energy absorption capacity of the structure is increased by 26%compared to that of a regular circular cross-section tube.Finally,the impact resistance of the bionic straight tapered tube structure is further improved through multi-objective optimization,promoting the engineering application and lightweight design of hybrid cross-section tubes. 展开更多
关键词 CRASHWORTHINESS tube inversion multi-objective optimization energy absorption
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Prevalence and risk factors associated with long COVID symptoms in children and adolescents in a southern province of Vietnam
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作者 Huynh Ngoc Linh Nguyen The Tan +5 位作者 Le Thi Minh Thu Nguyen Tu Loan Nguyen Thi To Uyen Le Thanh Thao Trang Truong Thanh Nam Doan Hoang Phu 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第3期119-128,I0001,I0002,共12页
Objective:To investigate the prevalence and risk factors associated with long COVID symptoms among children and adolescents who have recovered from COVID-19.Methods:This study applied a cross-sectional approach within... Objective:To investigate the prevalence and risk factors associated with long COVID symptoms among children and adolescents who have recovered from COVID-19.Methods:This study applied a cross-sectional approach within community settings in a southern province of Vietnam.A structured questionnaire featuring socio-demographic information and common long COVID symptoms was employed.Phi correlation coefficients assessed associations among pairs of long COVID symptoms.Additionally,multivariable logistic regression models were performed to investigate the risk factors of long COVID in recovered COVID-19 children and adolescents.Results:Among 422 participants,39.3%reported long COVID symptoms,with a prevalence of 45.2%(SD=0.5)in children and 22.2%(SD=0.4)in adolescents.Common symptoms reported were cough 34.6%(SD=0.5),fatigue 20.6%(SD=0.4),shortness of breath 10.9%(SD=0.3),and lack of appetite 6.6%(SD=0.3).Concerning risk factors of long COVID,a higher risk was observed among demographic groups,including girls(OR 1.25,95%CI 1.15-1.37;P<0.001,reference:boys),children compared to adolescents(OR 1.24,95%CI 1.12-1.37;P<0.001),overweight individuals(OR 1.14,95%CI 1.02-1.27;P=0.018,reference:healthy weight),and participants without any COVID-19 vaccination(OR 1.36,95%CI 1.20-1.54;P<0.001),or have received only one single dose(OR 1.35,95%CI 1.10-1.64;P=0.004)compared to those who have received two doses.Besides,patients with a COVID-19 treatment duration exceeding two weeks also had a higher risk of long COVID(OR 1.32,95%CI 1.09-1.60;P=0.003)than those who recovered less than seven days.Conclusions:The insights from this study provide crucial guidance for predicting the factors associated with the occurrence of long COVID in pediatric patients,contributing to strategic interventions aimed at mitigating the long COVID risks among children and adolescents in Vietnam. 展开更多
关键词 Long COVID PREVALENCE Risk factors Children ADOLESCENT VIETNAM
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Relationship between the rs2241766 ADIPOQ Polymorphism in a Black African Population and the Occurrence of Type 2 Diabetes
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作者 Aude Syntia Mbang Bengone Rosalie Nikiema-Ndong +6 位作者 Elisabeth Lendoye Alvine Sibylle Batou Edwige Nnegue Edzo Serge Bekale Daniela Nsame Frédéric Da Dari Félix Ovono Abessolo 《American Journal of Molecular Biology》 CAS 2024年第2期97-106,共10页
Background: Type 2 diabetes mellitus (T2DM) is a metabolic disease, characterized by chronic hyperglycemia. This pathology is linked to various genes whose interaction with the environment promotes its development. Th... Background: Type 2 diabetes mellitus (T2DM) is a metabolic disease, characterized by chronic hyperglycemia. This pathology is linked to various genes whose interaction with the environment promotes its development. The aim of this work was to determine the relationship between the rs2241766 (T/G) polymorphism of the ADIPOQ gene with type 2 diabetes in the black population. Material and Methods: This work was a case-control study, involving type 2 diabetics subjects (n = 94) and controls (n = 82). The study took place from September 2022 to September 2023. Patients were recruited in the Endocrinology Department of the Libreville University Hospital Center. Analysis was performed in the Biochemistry laboratory of the University of Health Sciences in Libreville and at the Research Institute of Health Sciences of Bobodioulasso. Genomic DNA was extracted using the protocol Qiagen kit and the PCR-RFLP method was used to determine the rs2241766 (T/G) polymorphism of the ADIPOQ gene. Results: Only 2 genotypes were found in this population, the TT genotype and the GT genotype. The proportions were not different between the two groups (p = 0.1095) neither the distribution of G and T alleles (p = 0.1095). On the other hand, the HDL hypocholesterolemia was frequent in subjects with the GT genotype compared to TT heterozygous (51.1% vs 48.9%, p = 0.0280;OR = 0.55 [0.30 - 1.01]). Conclusion: There was no association between the rs2241766 (T/G) variant of the ADIPOQ gene and the occurrence of type 2 diabetes in this population. On the other hand, a relationship between HDL hypocholesterolemia and the GT genotype has been established. 展开更多
关键词 Type 2 Diabetes Mellitus POLYMORPHISM rs2241766 ADIPOQ PCR-RFLP
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Effect of an Inclined Slots on the Power Consumption and Vortices Size in a Rushton Turbine Agitated Tank
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作者 Sarra Youcefi Mohamed Bouzit +1 位作者 Abdelkader Youcefi Abderrahim Mokhefi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第6期261-276,共16页
Mechanical agitation in baffled vessels with turbines plays a vital role in achieving homogeneous fluid mixing and promoting various transfer operations.Therefore,designing vessels with optimal energy efficiency and f... Mechanical agitation in baffled vessels with turbines plays a vital role in achieving homogeneous fluid mixing and promoting various transfer operations.Therefore,designing vessels with optimal energy efficiency and flow dynamics is essential to enhance operational performance and eliminate flow perturbations.Hence,the present research focuses on a numerical investigation of the impact of inclined slots with different angles installed at the side-wall of a cylindrical vessel equipped with a Rushton turbine.This study explores power consumption and vortex size while considering various rotation directions of the impeller with different rotation speeds.The numerical simulations are conducted for Reynolds numbers ranging from 104 to 105,using the RANS k-εturbulence model to govern the flow inside the stirred vessel,accounting for mass and momentum balances.The results have shown that the installation of slots reduces power consumption and vortex size compared to conventional vessel configu-rations.Moreover,increasing the slot angle from 0 to 32.5°further reduces energy consumption and vortex size,especially with negative rotation speeds.On the other hand,increasing the Reynolds numbers leads to a decrease in power consumption and an increase in vortex size.The present research therefore proposes a design for con-structing Rushton-turbine stirred vessels offering optimal operation,characterized by reduced energy consumption and minimized vortex size. 展开更多
关键词 Mixing Stirred tank Rushton turbine Inclined slots HYDRODYNAMIC Power consumption Vortices size
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Flexible Global Aggregation and Dynamic Client Selection for Federated Learning in Internet of Vehicles
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作者 Tariq Qayyum Zouheir Trabelsi +3 位作者 Asadullah Tariq Muhammad Ali Kadhim Hayawi Irfan Ud Din 《Computers, Materials & Continua》 SCIE EI 2023年第11期1739-1757,共19页
Federated Learning(FL)enables collaborative and privacy-preserving training of machine learning models within the Internet of Vehicles(IoV)realm.While FL effectively tackles privacy concerns,it also imposes significan... Federated Learning(FL)enables collaborative and privacy-preserving training of machine learning models within the Internet of Vehicles(IoV)realm.While FL effectively tackles privacy concerns,it also imposes significant resource requirements.In traditional FL,trained models are transmitted to a central server for global aggregation,typically in the cloud.This approach often leads to network congestion and bandwidth limitations when numerous devices communicate with the same server.The need for Flexible Global Aggregation and Dynamic Client Selection in FL for the IoV arises from the inherent characteristics of IoV environments.These include diverse and distributed data sources,varying data quality,and limited communication resources.By employing dynamic client selection,we can prioritize relevant and high-quality data sources,enhancing model accuracy.To address this issue,we propose an FL framework that selects global aggregation nodes dynamically rather than a single fixed aggregator.Flexible global aggregation ensures efficient utilization of limited network resources while accommodating the dynamic nature of IoV data sources.This approach optimizes both model performance and resource allocation,making FL in IoV more effective and adaptable.The selection of the global aggregation node is based on workload and communication speed considerations.Additionally,our framework overcomes the constraints associated with network,computational,and energy resources in the IoV environment by implementing a client selection algorithm that dynamically adjusts participants according to predefined parameters.Our approach surpasses Federated Averaging(FedAvg)and Hierarchical FL(HFL)regarding energy consumption,delay,and accuracy,yielding superior results. 展开更多
关键词 IoT Federated Learning SENSORS IoV OMNET++ edge computing
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Friction welding influence on microstructure,microhardness and hardness behavior of CrNiMo steel(AISI 316)
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作者 Ammar Jabbar Hassan Billel Cheniti +3 位作者 Brahim Belkessa Taoufik Boukharouba Djamel Miroud Nacer-Eddine Titouche 《China Welding》 CAS 2023年第3期21-27,共7页
For joining high Cr,Ni and Mo austenitic stainless steel(AISI 316)by direct drive friction welding(DDFW),with friction weld-ing conditions:rotation speed of 3000 r/min,friction time of 10 s,friction pressure of 130 MP... For joining high Cr,Ni and Mo austenitic stainless steel(AISI 316)by direct drive friction welding(DDFW),with friction weld-ing conditions:rotation speed of 3000 r/min,friction time of 10 s,friction pressure of 130 MPa,forge time of 5 s and forge pressure of 260 MPa.The results of microstructure showed that the temperature at the interface reached 819℃while forge applied between 357-237℃,which subdivided welded joint into four distinct regions of highly plastically deformed zone(HPDZ),thermo-mechanically affected zone(TMAZ),heat affected zone(HAZ)and the base metal,with grain size about 10µm,100µm,90µm and 30µm respectively.These re-gions were created due to dynamic recrystallization(DRX)at the interface and thermo-mechanical deformation with heat diffusion in the neighboring regions.Whereas,high level of microhardness about 300 HV0.1 and hardness roughly 240 Hv10 at the interface due to HPDZ creation while low level of 240 HV0.1 for microhardness and moderately of 205 HV10 for hardness in neighboring regions. 展开更多
关键词 friction welding austenitic stainless steel MICROSTRUCTURE MICROHARDNESS HARDNESS
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Investigation of the sodium storage mechanism of iron fluoride hydrate cathodes using X-ray absorption spectroscopy and mossbauer spectroscopy
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作者 Ghulam Ali Muhammad Akbar +4 位作者 Faiza Jan Iftikhar Qamar Wali Beata Kalska Szostko Dariusz Satuła Kyung Yoon Chung 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期535-542,I0014,共9页
Elucidation of a reaction mechanism is the most critical aspect for designing electrodes for highperformance secondary batteries.Herein,we investigate the sodium insertion/extraction into an iron fluoride hydrate(FeF_... Elucidation of a reaction mechanism is the most critical aspect for designing electrodes for highperformance secondary batteries.Herein,we investigate the sodium insertion/extraction into an iron fluoride hydrate(FeF_(3)·0.5H_(2)O)electrode for sodium-ion batteries(SIBs).The electrode material is prepared by employing an ionic liquid 1-butyl-3-methylimidazolium-tetrafluoroborate,which serves as a reaction medium and precursor for F^(-)ions.The crystal structure of FeF_(3)·0.5H_(2)O is observed as pyrochlore type with large open 3-D tunnels and a unit cell volume of 1129A^(3).The morphology of FeF_(3)·0.5H_(2)O is spherical shape with a mesoporous structure.The microstructure analysis reveals primary particle size of around 10 nm.The FeF_(3)·0.5H_(2)O cathode exhibits stable discharge capacities of 158,210,and 284 mA h g^(-1) in three different potential ranges of 1.5-4.5,1.2-4.5,and 1.0-4.5 V,respectively at 0.05 C rate.The specific capacities remained stable in over 50 cycles in all three potential ranges,while the rate capability was best in the potential range of 1.5-4.5 V.The electrochemical sodium storage mechanism is studied using X-ray absorption spectroscopy,indicating higher conversion at a more discharged state.Ex-situ M?ssbauer spectroscopy strengthens the results for reversible reduction/oxidation of Fe.These results will be favorable to establish high-performance cathode materials with selective voltage window for SIBs. 展开更多
关键词 Iron fluoride Sodium-ion batteries PYROCHLORE X-ray absorption spectroscopy Mössbauer spectroscopy
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Effect of Acacia albida Leaf Supplementation on Reproductive Parameters and Pre-Weaning Growth of Arabian Lambs
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作者 Oumar Moucthar Kodbe Miegoue Emile +5 位作者 Mouchili Mama Azoutane Julien Ousmane Issa Abdel Djalil Kwayep Nyah Cedric Taboumda Evariste Tendonkeng Fernand 《Open Journal of Animal Sciences》 CAS 2023年第1期46-59,共14页
A trial on Acacia albida leaf supplementation on reproductive parameters and pre-weaning growth of Arabian lambs was conducted from September 2020 to May 2021 at the small ruminant station of the Livestock Research In... A trial on Acacia albida leaf supplementation on reproductive parameters and pre-weaning growth of Arabian lambs was conducted from September 2020 to May 2021 at the small ruminant station of the Livestock Research Institute for Development (IRED) in N’Djamena, Chad. Forty-eight (48) Arabian sheep (45 non-pregnant females and 3 males for a sex ratio of 1 ram to 15 ewes) with an average weight of 20.3 ± 1.2 kg and aged approximately 2 years were divided into 3 groups of 15 ewes each. The supplemented group received in addition to the dominant forage of the pasture (300 g of Dactyloctenium aegyptium + 300 g of Cenchrus ciliaris + 600 g of Panicum maximum), 400 g and 600 g of Acacia albida leaves/animal/day while the control group received only 300 g of Dactyloctenium aegyptium + 300 g of Cenchrus ciliaris + 600 g of Panicum maximum. From the results of this study, it appears that the ewes that received 400 g of Acacia albida leaves had a significantly higher fertility rate and birth mortality rate (93.03% and 6.25% respectively). Animals in the control group had a significantly higher pre-weaning mortality rate than those receiving Acacia albida leaves as a supplement (16.66% versus 6.66% and 14.28% respectively). The highest weight of the lambs was observed in the ration supplemented with 600 g of Acacia albida leaves (12209.66 g). The total weight gain, as well as the average daily weight gain of the lambs receiving the 600 g Acacia albida leaf ration was significantly higher than those of the other rations. Supplementation with 400 g and 600 g of Acacia albida leaves can be recommended as a protein supplement for breeding ewes and pre-weaned lambs. 展开更多
关键词 Acacia albida LAMB GROWTH WEANING Supplementation
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Identification of Software Bugs by Analyzing Natural Language-Based Requirements Using Optimized Deep Learning Features
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作者 Qazi Mazhar ul Haq Fahim Arif +4 位作者 Khursheed Aurangzeb Noor ul Ain Javed Ali Khan Saddaf Rubab Muhammad Shahid Anwar 《Computers, Materials & Continua》 SCIE EI 2024年第3期4379-4397,共19页
Software project outcomes heavily depend on natural language requirements,often causing diverse interpretations and issues like ambiguities and incomplete or faulty requirements.Researchers are exploring machine learn... Software project outcomes heavily depend on natural language requirements,often causing diverse interpretations and issues like ambiguities and incomplete or faulty requirements.Researchers are exploring machine learning to predict software bugs,but a more precise and general approach is needed.Accurate bug prediction is crucial for software evolution and user training,prompting an investigation into deep and ensemble learning methods.However,these studies are not generalized and efficient when extended to other datasets.Therefore,this paper proposed a hybrid approach combining multiple techniques to explore their effectiveness on bug identification problems.The methods involved feature selection,which is used to reduce the dimensionality and redundancy of features and select only the relevant ones;transfer learning is used to train and test the model on different datasets to analyze how much of the learning is passed to other datasets,and ensemble method is utilized to explore the increase in performance upon combining multiple classifiers in a model.Four National Aeronautics and Space Administration(NASA)and four Promise datasets are used in the study,showing an increase in the model’s performance by providing better Area Under the Receiver Operating Characteristic Curve(AUC-ROC)values when different classifiers were combined.It reveals that using an amalgam of techniques such as those used in this study,feature selection,transfer learning,and ensemble methods prove helpful in optimizing the software bug prediction models and providing high-performing,useful end mode. 展开更多
关键词 Natural language processing software bug prediction transfer learning ensemble learning feature selection
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Overview of cytokines and nitric oxide involvement in immuno-pathogenesis of inflammatory bowel diseases 被引量:31
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作者 Imene Soufli Ryma Toumi +1 位作者 Hayet Rafa Chafia Touil-Boukoffa 《World Journal of Gastrointestinal Pharmacology and Therapeutics》 CAS 2016年第3期353-360,共8页
Inflammatory bowel diseases(IBDs), including Crohn's disease and ulcerative colitis are complex disorders with undetermined etiology. Several hypotheses suggest that IBDs result from an abnormal immune response ag... Inflammatory bowel diseases(IBDs), including Crohn's disease and ulcerative colitis are complex disorders with undetermined etiology. Several hypotheses suggest that IBDs result from an abnormal immune response against endogenous flora and luminal antigens in genetically susceptible individuals. The dysfunction of the mucosal immune response is implicated in the pathogenesis of IBD. The balance between pro-inflammatory cytokines [tumor necrosis factor(TNF)-α, interleukin(IL)-1b, IL-8, and IL-17A], anti-inflammatory cytokines(IL-4 and IL-13), and immunoregulatory cytokines(IL-10 and transforming growth factors b) is disturbed. Moreover, evidence from animal and clinical studies demonstrate a positive correlation between an increased concentration of nitric oxide(NO) and the severity of the disease. Interestingly, proinflammatory cytokines are involved in the up-regulation of inducible oxide synthase(iN OS) expression in IBD. However, anti-inflammatory and immunoregulatory cytokines are responsible for the negative regulation of iN OS. A positive correlation between NO production and increased pro-inflammatory cytokine levels(TNF-α, IL-6, IL-17, IL-12, and interferon-γ) were reported in patients with IBD. This review focuses on the role of cytokines in intestinal inflammation and their relationship with NO in IBD. 展开更多
关键词 Inflammatory bowel disease CYTOKINES NITRIC OXIDE INDUCIBLE NITRIC OXIDE synthase IMMUNO PATHOGENESIS
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High prevalence of multidrug-resistance in Acinetobacter baumannii and dissemination of carbapenemase-encoding genes bla_(OXA-23-like),bla_(OXA-24-like)and bla_(NDM-1) in Algiers hospitals 被引量:20
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作者 Khadidja Khorsi Yamina Messai +2 位作者 Moufida Hamidi Houria Ammari Rabah Bakour 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2015年第6期439-447,共9页
Objective:To assess and characterize antibiotic resistance in Acinetobacter baumannii strains recovered from 5 health-care facilities in Algiers.Methods:Antibiotic susceptibility testing was performed by agar diffusio... Objective:To assess and characterize antibiotic resistance in Acinetobacter baumannii strains recovered from 5 health-care facilities in Algiers.Methods:Antibiotic susceptibility testing was performed by agar diffusion and agar dilution methods,resistance genes were identified by PCR and sequencing,and molecular typing of isolates was carried out by enterobacterial repetitive intergenic consensus-PCR(ERIC-PCR).Results:Among 125 tested isolates,117(93.6% ) were multidrug-resistant.of which 94(75.2% ) were imipenem resistant.The bla_(ADC)and bla_(OXA-51-like) genes were detected in all isolates,in association with ISAba I sequence in 84% and 8% (imipenem resistant) of isolates,respectively.The bla_(OXA-23-like) and bla_(OXA-24-like)carbapenemase genes were delected in 67.02% and 20.21% of imipenem-resistant isolates,respectively.The bla_(OXA-23-like) gene is linked to ISAba1 or ISAba4 elements.The metallo-β-lactamase NDM-1 gene was found in 10(10.6% ) imipenem-resisianl strains from three hospitals,it is linked to ISAba125 clement in nine strains.Extended spectrum β-lactamases production was not detected.Imipenem and cefotaxime resistance phenolypes could not be transferred to Escherichia coli by conjugation.Outer membrane protein CarO gene was not delected in four imipenem-resisianl isolates.The aac(6')-1b.sul1,sul2,tetA and tetB genes were present in 5.31% .36.17% .77.65% .1.06% and 65.92% of strains,respectively.Class 1 integrons were detected in 23.4% strains.KRIC-PCR typing showed a genetic diversity among bla_(OXA-23-like) and bla_(OXA-24-like) positive strains,while clonality was observed among bla_(NDM-1)positives.Conclusions:This study highlighted the high prevalence of imipenem resistance in Acinetobacter baumannii in Algiers hospitals mediated mainly by bla_(OXA-23-like),bla_(OXA-24-like),and bla_(NDM-1) genes. 展开更多
关键词 ACINETOBACTER BAUMANNII MULTIDRUG-RESISTANCE CARBAPENEMASE carO Hospital Algiers
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Survey and technological analysis of laser and its defense applications 被引量:10
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作者 Syed Affan Ahmed Mujahid Mohsin Syed Muhammad Zubair Ali 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第2期583-592,共10页
The laser technology has made remarkable progress over the past couple of decades.It is being widely employed in diverse domains,such as holography,space sciences,spectroscopy,medical sciences,micro and power electron... The laser technology has made remarkable progress over the past couple of decades.It is being widely employed in diverse domains,such as holography,space sciences,spectroscopy,medical sciences,micro and power electronics,industrial engineering,and most distinctively,as directed energy military weapons.Owing to their active transmissions,laser systems are similar to microwave radars to some extent;however,unlike conventional radars,the laser operates at very high frequencies thus making it a potent enabler of narrow-beam and high energy aerial deployments,both in offensive and defensive roles.In modern avionics systems,laser target indicators and beam riders are the most common devices that are used to direct the Laser Guided Weapons(LGW)accurately to the ground targets.Additionally,compact size and outstanding angular resolution of laser-based systems motivate their use for drones and unmanned aerial applications.Moreover,the narrow-beam divergence of laser emissions offers a low probability of intercept,making it a suitable contender for secure transmissions and safety-critical operations.Furthermore,the developments in space sciences and laser technology have given synergistic potential outcomes to use laser systems in space operations.This paper comprehensively reviews laser applications and projects for strategic defense actions on the ground or in space.Additionally,a detailed analysis has been done on recent advancements of the laser technology for target indicators and range-finders.It also reviews the advancements in the field of laser communications for surveillance,its earlier state of the art,and ongoing scientific research and advancements in the domain of high energy directed laser weapons that have revolutionized the evolving military battlefield.Besides offering a comprehensive taxonomy,the paper also critically analyzes some of the recent contributions in the associated domains. 展开更多
关键词 Laser systems Laser military applications Directed energy weapons Non-lethal weapons Laser military projects SURVEY TAXONOMY
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Analysis of Earthquake-Triggered Failure Mechanisms of Slopes and Sliding Surfaces 被引量:10
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作者 WANG Jian YAO Lingkan Arshad Hussain 《Journal of Mountain Science》 SCIE CSCD 2010年第3期282-290,共9页
Earthquake-induced landslides along the Dujiangyan-Yingxiu highway after the Ms 8.0 Wenchuan earthquake in 2008 were investigated.It was found that:(1) slopes were shattered and damaged during the earthquake and open ... Earthquake-induced landslides along the Dujiangyan-Yingxiu highway after the Ms 8.0 Wenchuan earthquake in 2008 were investigated.It was found that:(1) slopes were shattered and damaged during the earthquake and open tension cracks formed on the tops of the slopes;(2) the upper parts of slopes collapsed and slid,while the lower parts remained basically intact,indicating that the upper parts of slopes would be damaged more heavily than the lower parts during an earthquake.Large-scale shaking table model tests were conducted to study failure behavior of slopes under the Wenchuan seismic wave,which reproduced the process of deformation and failure of slopes.Tension cracks emerged at the top and upper part of model,while the bottom of the model remained intact,consistent with field investigations.Depth of the tension crack at the top of model is 32 cm,i.e.,3.2 m compared to the prototype natural slope with a height of 14 m when the length scale ratio(proto/model) is 10.Acceleration at the top of the slope was almost twice as large as that at the toe when the measured accelerations on shaking table are 4.85 m/s2 and 6.49 m/s2,which means that seismic force at the top of the slope is twice the magnitude of that at the toe.By use of the dynamic-strength-reduction method,numerical simulation was conducted to explore the process and mechanism of formation of the sliding surface,with other quantified information.The earthquake-induced failure surfaces commonly consist of tension cracks and shear zones.Within 5 m from the top of the slope,the dynamic sliding surface will be about 1 m shallower than the pseudo-static sliding surface in a horizontal direction when the peak ground acceleration(PGA) is 1 m/s2;the dynamic sliding surface will be about 2 m deeper than the pseudo-static sliding surface in a horizontal direction when the PGA is 10 m/s2,and the depths of the dynamic sliding surface and the pseudo-static sliding surface will be almost the same when the PGA is 2 m/s2.Based on these findings,it is suggested that the key point of anti-seismic design,as well as for mitigation of post-earthquake,secondary mountain hazards,is to prevent tension cracks from forming in the upper part of the slope.Therefore,the depth of tension cracks in slope surfaces is the key to reinforcement of slopes.The depth of the sliding surface from the pseudo-static method can be a reference for slope reinforcement mitigation. 展开更多
关键词 边坡加固 滑动面 大地震 大型振动台模型试验 破坏机理 引发 表面张力 峰值加速度
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Antihydatic and immunomodulatory effects of Punica granatum peel aqueous extract in a murine model of echinococcosis 被引量:5
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作者 Moussa Labsi Lila Khelifi +2 位作者 Dalila Mezioug Imene Soufli Chafia Touil-Boukoffa 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第3期208-216,共9页
Objective:To investigate the effect of pomegranate peel aqueous extract(PGE) on the development of secondary experimental echinococcosis and on the viability of Echinococcux granulosus protoscoleces,and the immunomodu... Objective:To investigate the effect of pomegranate peel aqueous extract(PGE) on the development of secondary experimental echinococcosis and on the viability of Echinococcux granulosus protoscoleces,and the immunomodulatory properties of PGE.Methods:Swiss mice were inoculated intraperitoneally with viable protoscoleces.Then,PGE was orally administered daily during cystic echinococcosis development.Cyst development and hepatic damage were macroscopically and histologically analyzed.The production of nitric oxide and TNF-α was assessed in plasma and the hepatic expression of iNOS.TNF-α,NF-κB and CD68 was examined.Moreover,protoscoleces were cultured and treated with different concentrations of PGE.Results:It was observed that in vitro treatment of protoscoleces caused a significant decrease in viability in a PGE-dose-dependent manner.In vivo,after treatment of cystic echinococcosis infected mice with PGE,a significant decrease in nitric oxide levels(P<0.000 1)and TNF-α levels(P<0.001) was observed.This decline was strongly related to the inhibition of cyst development(rate of hydatid cyst growth inhibition=63.08%) and a decrease in CD68 expression in both the pericystic layer of hepatic hydatid cysts and liver tissue(P<0.000 1).A significant diminution of iNOS,TNF-α and NF-κB expression was also observed in liver tissue of treated mice(P<0.000 1).Conclusions:Our results indicate an antihydatic scolicidal effect and immunomodulatory properties of PGE,suggesting its potential therapeutic role against Echinococcuss granulosus infection. 展开更多
关键词 POMEGRANATE PEEL aqueous extract Tumor NECROSIS factor-α iNOS Nuclear factor-κB
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Permeability and pressure distribution characteristics of the roadway surrounding rock in the damaged zone of an excavation 被引量:5
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作者 Xue Yi Gao Feng +1 位作者 Liu Xingguang Liang Xin 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第2期211-219,共9页
Research on the permeability and pressure distribution characteristics of the roadway surrounding rock in the excavation damaged zone(EDZ) is beneficial for the development of gas control technology. In this study, an... Research on the permeability and pressure distribution characteristics of the roadway surrounding rock in the excavation damaged zone(EDZ) is beneficial for the development of gas control technology. In this study, analytical solutions of stress and strain of the roadway surrounding rock were obtained, in which the creep deformation and strain softening were considered. Using the MTS815 rock mechanics testing system and a gas permeability testing system, permeability tests were conducted in the complete stress-strain process, and the evolution characteristics of permeability and strain were studied over the whole loading process. Based on the analytical solutions of stress and strain and the governing equation of gas seepage flow, this paper proposes a hydro-mechanical(HM) model, which considers three different zones around the roadway. Then the gas flow process in the roadway surrounding rock in three different zones was simulated according to the engineering geological conditions, thus obtaining the permeability and pressure distribution characteristics of the roadway surrounding rock in three different zones. These results show that the surrounding rock around the roadway can be divided into four regions-the full flow zone(FFZ), flow-shielding zone(FSZ), transitive flow zone(TFZ), and in-situ rock flow zone(IRFZ). These results could provide theoretical guidance for the improvement of gas extraction and gas control technology. 展开更多
关键词 巷道围岩 演化特征 压力分布 渗透性 开挖 全应力应变过程 破坏区 瓦斯治理技术
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COMBINED EFFECTS OF TEMPERATURE, IRRADIANCE AND SALINITY ON GROWTH OF DIATOM SKELETONEMA COSTATUM 被引量:5
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作者 颜天 周名江 钱培元 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第3期237-243,共7页
factor experiment was used to study the combined effects of temperature, irradiance and salinity on the growth of an HAB species diatom Skeletonema costatum (Grev.) Cleve. The results showed that temperature (12, 19, ... factor experiment was used to study the combined effects of temperature, irradiance and salinity on the growth of an HAB species diatom Skeletonema costatum (Grev.) Cleve. The results showed that temperature (12, 19, 25, 32℃), irradiance ((0.02, 0.08, 0.3, 1.6)×10 16 quanta/(s·cm 2)) and salinity (10, 18, 25, 30, 35) significantly influenced the growth of this species. There were interactive effects between any two of and among all three physical factors on the growth. In the experiment, the most optimal growth condition for S. costatum was temparature of 25℃, salinity of 18-35 and irradiance of 1.6×10 16 quanta/(s·cm 2). The results indicated S. costatum could divide at higher rate and were more likely to bloom under high temperature and high illumination from spring to fall. It was able to distribute widely in ocean and estuary due to its adaptation to a wide range of salinities. 展开更多
关键词 硅藻属 盐分 温度 光强度 植物生长 环境因素
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Effect of interlayer anions on chromium removal using Mg–Al layered double hydroxides:Kinetic,equilibrium and thermodynamic studies 被引量:3
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作者 Mohamed Khitous Zineb Salem Djamila Halliche 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第4期433-445,共13页
The influence of interlayer anions such as NO3-, SO42-and Cl-on Mg–Al hydrotalcites for Cr(VI) removal from aqueous solution was studied. The structure of the prepared LDHs was characterized by XRD, SEM, FTIR, TGA, B... The influence of interlayer anions such as NO3-, SO42-and Cl-on Mg–Al hydrotalcites for Cr(VI) removal from aqueous solution was studied. The structure of the prepared LDHs was characterized by XRD, SEM, FTIR, TGA, BET surface area and p Hzpc. The sorbent ability and sorption mechanisms were also investigated. The LDHs exhibit high removal for Cr(VI), and the sorbed amount depends on the nature of interlayer anion, which decreased in the following order: NO3-N Cl-N SO42-. Nitrate-containing LDH reached a Cr(VI) sorption equilibrium within only 30 min. The effects of operating conditions, including initial concentration, solution p H, agitation time and sorbent amount have been studied in batch mode. The optimum conditions were observed at an initial concentration of 100 mg·L-1, p H = 6, agitation time of 60 min and a sorbent dose of 2 g·L-1. The equilibrium data were fitted to the Langmuir, Freundlich and Dubinin–Radushkevich isotherm models. The Langmuir model was found to sufficiently describe the sorption process, offering a maximum sorption capacity of 71.91 mg·g-1. The sorption kinetic follows pseudo-second-order reaction with high accuracy. Thermodynamic parameters suggested that the sorption process is spontaneous and endothermic in nature. 展开更多
关键词 镁铝水滑石 吸附平衡 层状双氢氧化物 阴离子 动力学 热力学 去除效果 层间
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Gene-gene,gene-environment,gene-nutrient interactions and single nucleotide polymorphisms of inflammatory cytokines 被引量:4
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作者 Amina Nadeem Sadaf Mumtaz +4 位作者 Abdul Khaliq Naveed Muhammad Aslam Arif Siddiqui Ghulam Mustafa Lodhi Tausif Ahmad 《World Journal of Diabetes》 SCIE CAS 2015年第4期642-647,共6页
Inflammation plays a significant role in the etiology of type 2 diabetes mellitus(T2DM).The rise in the pro-inflammatory cytokines is the essential step in glucotoxicity and lipotoxicity induced mitochondrial injury,o... Inflammation plays a significant role in the etiology of type 2 diabetes mellitus(T2DM).The rise in the pro-inflammatory cytokines is the essential step in glucotoxicity and lipotoxicity induced mitochondrial injury,oxidative stress and beta cell apoptosis in T2 DM.Among the recognized markers are interleukin(IL)-6,IL-1,IL-10,IL-18,tissue necrosis factor-alpha(TNF-α),C-reactive protein,resistin,adiponectin,tissue plasminogen activator,fibrinogen and heptoglobins.Diabetes mellitus has firm genetic and very strong environmental influence; exhibiting a polygenic mode of inheritance.Many single nucleotide polymorphisms(SNPs) in various genes including those of pro and antiinflammatory cytokines have been reported as a risk for T2 DM.Not all the SNPs have been confirmed by unifying results in different studies and wide variations have been reported in various ethnic groups.The inter-ethnic variations can be explained by the fact that gene expression may be regulated by gene-gene,gene-environment and gene-nutrient interactions.This review highlights the impact of these interactions on determining the role of single nucleotide polymorphism of IL-6,TNF-α,resistin and adiponectin in pathogenesis of T2 DM. 展开更多
关键词 Cytokines GENE-ENVIRONMENT INTERACTION Diabetes MELLITUS Single NUCLEOTIDE polymorphism Gene-gene INTERACTION
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Landslide susceptibility analysis of Karakoram highway using analytical hierarchy process and scoops 3D 被引量:3
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作者 Barira RASHID Javed IQBAL SU Li-jun 《Journal of Mountain Science》 SCIE CSCD 2020年第7期1596-1612,共17页
Landslides are prevalent,regular,and expensive hazards in the Karakoram Highway(KKH)region.The KKH connects Pakistan with China in the present China-Pakistan Economic Corridor(CPEC)context.This region has not only imm... Landslides are prevalent,regular,and expensive hazards in the Karakoram Highway(KKH)region.The KKH connects Pakistan with China in the present China-Pakistan Economic Corridor(CPEC)context.This region has not only immense economic importance but also ecological significance.The purpose of the study was to map the landslide-prone areas along KKH using two different techniquesAnalytical Hierarchy Process(AHP)and Scoops 3 D model.The causative parameters for running AHP include the lithology,presence of thrust,land use land cover,precipitation,and Digital Elevation Model(DEM)derived variables(slope,curvature,aspect,and elevation).The AHP derived final landslide susceptibility map was classified into four zones,i.e.,low,moderate,high,and extremely high.Over 80%of the study area falls under the moderate(43%)and high(40%)landslide susceptible zones.To assess the slope stability of the study area,the Scoops 3 D model was used by integrating with the earthquake loading data.The results of the limit equilibrium analysis categorized the area into four groups(low,moderate,high,and extremely high mass)of slope failure.The areas around Main Mantle Thrust(MMT)including Dubair,Jijal,and Kohistan regions,had high volumes of potential slope failures.The results from AHP and Scoops 3 D techniques were validated with the landslides inventory record of the Geological Survey of Pakistan and Google Earth.The results from both the techniques showed similar output that coincides with the known landslides areas.However,Scoops 3 D provides not only susceptible zones but also the range of volume of the potential slope failures.Further,these techniques could be used in other mountainous areas,which could help in the landslide mitigation measures. 展开更多
关键词 Landslide mapping Landslide hazard zonation Analytical Hierarchy Process(AHP) Scoops 3D China Pakistan Economic Corridor(CPEC) Karakoram Highway
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