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Epidemiological, Clinical, and Evolutionary Profile of Children Admitted to the Pediatric Emergency Department of the Maroua Regional Hospital, Cameroon
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作者 Soureya Haman Kamo Selangaï Héléne +4 位作者 Enyama Dominique Abouame Palma Haoua Salihou Sadjo Mekone Nkwele Isabelle Nguefack Félicitée 《Open Journal of Pediatrics》 2024年第5期878-888,共11页
Introduction: Pediatric emergencies in developing countries are associated with high morbidity and mortality. The Maroua Regional Hospital (MRH) is one of the referral centers for pediatric emergencies in the Far nort... Introduction: Pediatric emergencies in developing countries are associated with high morbidity and mortality. The Maroua Regional Hospital (MRH) is one of the referral centers for pediatric emergencies in the Far north region of Cameroon. Pediatric emergencies are frequent in Maroua and are associated with significant mortality. The aim of our study is to determine the epidemiological, clinical, and evolutionary profile of children admitted to the pediatric emergency department of the HRM. Methods: We conducted an observational, descriptive, and retrospective study over a period from April 10, 2023 to April 10, 2024, focusing on the records of patients admitted to the pediatric emergency department of the MRH. The variables studied included epidemiological, clinical, and evolutionary characteristics. Data analysis was performed using CSPro version 8.01 and SPSS version 27.0. Results: We included 1027 patients;the sex ratio was 1.2 infants under 2 years represented 54.33%. The main reasons for consultation were fever (62.22%) and seizures (30.18%). The most frequently prescribed additional test was the Complete Blood Count (CBC), performed in 97.37% of cases. The most common pathologies were severe malaria (45.18%), broncho-pulmonary infections (15.48%), and bacterial meningitis (12.26%). At admission, 32.9% were transfused. There were 68 deaths, representing 6.67%, and 86% of the deaths occurred within 24 hours of admission. The leading cause of death was severe malaria, with 28 (41.17%) cases. Conclusion: Febrile illnesses were the main reason for consultation, and mortality was linked to severe malaria. Therefore, in addition to the other preventive methods already used against malaria, it is recommended to consider the use of the malaria vaccine. 展开更多
关键词 Pediatric emergencies MALARIA Cameroon
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Deformable Catalytic Material Derived from Mechanical Flexibility for Hydrogen Evolution Reaction 被引量:2
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作者 Fengshun Wang Lingbin Xie +7 位作者 Ning Sun Ting Zhi Mengyang Zhang Yang Liu Zhongzhong Luo Lanhua Yi Qiang Zhao Longlu Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期287-311,共25页
Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent year... Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent years,deformable catalysts for HER have made great progress and would become a research hotspot.The catalytic activities of deformable catalysts could be adjustable by the strain engineering and surface reconfiguration.The surface curvature of flexible catalytic materials is closely related to the electrocatalytic HER properties.Here,firstly,we systematically summarized self-adaptive catalytic performance of deformable catalysts and various micro–nanostructures evolution in catalytic HER process.Secondly,a series of strategies to design highly active catalysts based on the mechanical flexibility of lowdimensional nanomaterials were summarized.Last but not least,we presented the challenges and prospects of the study of flexible and deformable micro–nanostructures of electrocatalysts,which would further deepen the understanding of catalytic mechanisms of deformable HER catalyst. 展开更多
关键词 Deformable catalytic material Micro-nanostructures evolution Mechanical flexibility Hydrogen evolution reaction
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Valence electronic engineering of superhydrophilic Dy-evoked Ni-MOF outperforming RuO_(2) for highly efficient electrocatalytic oxygen evolution 被引量:1
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作者 Zhiyang Huang Miao Liao +6 位作者 Shifan Zhang Lixia Wang Mingcheng Gao Zuyang Luo Tayirjan Taylor Isimjan Bao Wang Xiulin Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期244-252,I0007,共10页
Tackling the problem of poor conductivity and catalytic stability of pristine metal-organic frameworks(MOFs) is crucial to improve their oxygen evolution reaction(OER) performance.Herein,we introduce a novel strategy ... Tackling the problem of poor conductivity and catalytic stability of pristine metal-organic frameworks(MOFs) is crucial to improve their oxygen evolution reaction(OER) performance.Herein,we introduce a novel strategy of dysprosium(Dy) doping,using the unique 4f orbitals of this rare earth element to enhance electrocatalytic activity of MOFs.Our method involves constructing Dy-doped Ni-MOF(Dy@Ni-MOF) nanoneedles on carbon cloth via a Dy-induced valence electronic perturbation approach.Experiments and density functional theory(DFT) calculations reveal that Dy doping can effectively modify the electronic structure of the Ni active centers and foster a strong electronic interaction between Ni and Dy.The resulting benefits include a reduced work function and a closer proximity of the d-band center to the Fermi level,which is conducive to improving electrical conductivity and promoting the adsorption of oxygen-containing intermediates.Furthermore,the Dy@Ni-MOF achieves superhydrophilicity,ensuring effective electrolyte contact and thus accelerating reaction kinetics,Ex-situ and in-situ analysis results manifest Dy_(2)O_(3)/NiOOH as the actual active species.Therefore,Dy@Ni-MOF shows impressive OER performance,significantly surpassing Ni-MOF.Besides,the overall water splitting device with Dy@NiMOF as an anode delivers a low cell voltage of 1.51 V at 10 mA cm^(-2) and demonstrates long-term stability for 100 h,positioning it as a promising substitute for precious metal catalysts. 展开更多
关键词 Dy@Ni-MOF Dy incorporation Electronic interaction SUPERHYDROPHILICITY Oxygen evolution reaction
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Microwave shock motivating the Sr substitution of 2D porous GdFeO_(3) perovskite for highly active oxygen evolution 被引量:1
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作者 Jinglin Xian Huiyu Jiang +10 位作者 Zhiao Wu Huimin Yu Kaisi Liu Miao Fan Rong Hu Guangyu Fang Liyun Wei Jingyan Cai Weilin Xu Huanyu Jin Jun Wan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期232-241,I0006,共11页
The incorporation of partial A-site substitution in perovskite oxides represents a promising strategy for precisely controlling the electronic configuration and enhancing its intrinsic catalytic activity.Conventional ... The incorporation of partial A-site substitution in perovskite oxides represents a promising strategy for precisely controlling the electronic configuration and enhancing its intrinsic catalytic activity.Conventional methods for A-site substitution typically involve prolonged high-temperature processes.While these processes promote the development of unique nanostructures with highly exposed active sites,they often result in the uncontrolled configuration of introduced elements.Herein,we present a novel approach for synthesizing two-dimensional(2D)porous GdFeO_(3) perovskite with A-site strontium(Sr)substitution utilizing microwave shock method.This technique enables precise control of the Sr content and simultaneous construction of 2D porous structures in one step,capitalizing on the advantages of rapid heating and cooling(temperature~1100 K,rate~70 K s^(-1)).The active sites of this oxygen-rich defect structure can be clearly revealed through the simulation of the electronic configuration and the comprehensive analysis of the crystal structure.For electrocatalytic oxygen evolution reaction application,the synthesized 2D porous Gd_(0.8)Sr_(0.2)FeO_(3) electrocatalyst exhibits an exceptional overpotential of 294 mV at a current density of 10 mA cm^(-2)and a small Tafel slope of 55.85 mV dec^(-1)in alkaline electrolytes.This study offers a fresh perspective on designing crystal configurations and the construction of nanostructures in perovskite. 展开更多
关键词 2D materials PEROVSKITE MICROWAVE ELECTROCATALYSIS Oxygen evolution reaction
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High-speed penetration of ogive-nose projectiles into thick concrete targets:Tests and a projectile nose evolution model 被引量:1
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作者 Xu Li Yan Liu +4 位作者 Junbo Yan Zhenqing Shi Hongfu Wang Yingliang Xu Fenglei Huang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期553-571,共19页
The majority of the projectiles used in the hypersonic penetration study are solid flat-nosed cylindrical projectiles with a diameter of less than 20 mm.This study aims to fill the gap in the experimental and analytic... The majority of the projectiles used in the hypersonic penetration study are solid flat-nosed cylindrical projectiles with a diameter of less than 20 mm.This study aims to fill the gap in the experimental and analytical study of the evolution of the nose shape of larger hollow projectiles under hypersonic penetration.In the hypersonic penetration test,eight ogive-nose AerMet100 steel projectiles with a diameter of 40 mm were launched to hit concrete targets with impact velocities that ranged from 1351 to 1877 m/s.Severe erosion of the projectiles was observed during high-speed penetration of heterogeneous targets,and apparent localized mushrooming occurred in the front nose of recovered projectiles.By examining the damage to projectiles,a linear relationship was found between the relative length reduction rate and the initial kinetic energy of projectiles in different penetration tests.Furthermore,microscopic analysis revealed the forming mechanism of the localized mushrooming phenomenon for eroding penetration,i.e.,material spall erosion abrasion mechanism,material flow and redistribution abrasion mechanism and localized radial upsetting deformation mechanism.Finally,a model of highspeed penetration that included erosion was established on the basis of a model of the evolution of the projectile nose that considers radial upsetting;the model was validated by test data from the literature and the present study.Depending upon the impact velocity,v0,the projectile nose may behave as undistorted,radially distorted or hemispherical.Due to the effects of abrasion of the projectile and enhancement of radial upsetting on the duration and amplitude of the secondary rising segment in the pulse shape of projectile deceleration,the predicted DOP had an upper limit. 展开更多
关键词 High-speed penetration Concrete target EROSION Projectile nose evolution model
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Carbon Emission Effects Driven by Evolution of Chinese Dietary Structure from 1987 to 2020 被引量:1
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作者 ZHU Yuanyuan ZHANG Yan ZHU Xiaohua 《Chinese Geographical Science》 SCIE CSCD 2024年第1期181-194,共14页
Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research ob... Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research object(data excluding Hong Kong,Macao and Taiwan) and used the carbon emission coefficient method to quantitatively measure the food carbon emissions from 1987–2020,then analyzed the carbon emission effects under the evolution of dietary structure.The results showed that during the study period,the Chinese dietary structure gradually changed to a high-carbon consumption pattern.The dietary structure of urban residents developed to a balanced one,while that of rural residents developed to a high-quality one.During the study period,the per capita food carbon emissions and total food consumption of Chinese showed an increasing trend.The per capita food carbon emissions of residents in urban and rural showed an overall upward trend.The total food carbon emissions in urban increased significantly,while that in rural increased first and then decreased.The influence of beef and mutton on carbon emissions is the highest in dietary structure.Compared with the balanced dietary pattern,the food carbon emissions of Chinese residents had not yet reached the peak,but were evolving to a high-carbon consumption pattern. 展开更多
关键词 dietary structure structural evolution carbon emission effects carbon neutrality China
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Tuning electronic structure of RuO_(2)by single atom Zn and oxygen vacancies to boost oxygen evolution reaction in acidic medium 被引量:1
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作者 Qing Qin Tiantian Wang +7 位作者 Zijian Li Guolin Zhang Haeseong Jang Liqiang Hou Yu Wang Min Gyu Kim Shangguo Liu Xien Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期94-102,I0003,共10页
The poor stability of RuO_(2)electrocatalysts has been the primary obstacles for their practical application in polymer electrolyte membrane electrolyzers.To dramatically enhance the durability of RuO_(2)to construct ... The poor stability of RuO_(2)electrocatalysts has been the primary obstacles for their practical application in polymer electrolyte membrane electrolyzers.To dramatically enhance the durability of RuO_(2)to construct activity-stability trade-off model is full of significance but challenging.Herein,a single atom Zn stabilized RuO_(2)with enriched oxygen vacancies(SA Zn-RuO_(2))is developed as a promising alternative to iridium oxide for acidic oxygen evolution reaction(OER).Compared with commercial RuO_(2),the enhanced Ru–O bond strength of SA Zn-RuO_(2)by forming Zn-O-Ru local structure motif is favorable to stabilize surface Ru,while the electrons transferred from Zn single atoms to adjacent Ru atoms protects the Ru active sites from overoxidation.Simultaneously,the optimized surrounding electronic structure of Ru sites in SA ZnRuO_(2)decreases the adsorption energies of OER intermediates to reduce the reaction barrier.As a result,the representative SA Zn-RuO_(2)exhibits a low overpotential of 210 mV to achieve 10 mA cm^(-2)and a greatly enhanced durability than commercial RuO_(2).This work provides a promising dual-engineering strategy by coupling single atom doping and vacancy for the tradeoff of high activity and catalytic stability toward acidic OER. 展开更多
关键词 ELECTROCATALYST Acidic oxygen evolution reaction Electronic structure engineering DURABILITY Reaction barrier
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Evolution of microstructure and properties of a novel Ni-based superalloy during stress relief annealing 被引量:1
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作者 Lei Jia Heng Cui +3 位作者 Shufeng Yang Shaomin Lü Xingfei Xie Jinglong Qu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第8期1876-1889,共14页
We discussed the decrease in residual stress,precipitation evolution,and mechanical properties of GH4151 alloy in different annealing temperatures,which were studied by the scanning electron microscope(SEM),high-resol... We discussed the decrease in residual stress,precipitation evolution,and mechanical properties of GH4151 alloy in different annealing temperatures,which were studied by the scanning electron microscope(SEM),high-resolution transmission electron microscopy(HRTEM),and electron backscatter diffraction(EBSD).The findings reveal that annealing processing has a significant impact on diminishing residual stresses.As the annealing temperature rose from 950 to 1150℃,the majority of the residual stresses were relieved from 60.1 MPa down to 10.9 MPa.Moreover,the stress relaxation mechanism transitioned from being mainly controlled by dislocation slip to a combination of dislocation slip and grain boundary migration.Meanwhile,the annealing treatment promotes the decomposition of the Laves,accompanied by the precipitation ofμ-(Mo_(6)Co_(7))starting at 950℃ and reaching a maximum value at 1050℃.The tensile strength and plasticity of the annealing alloy at 1150℃ reached the maximum(1394 MPa,56.1%)which was 131%,200%fold than those of the as-cast alloy(1060 MPa,26.6%),but the oxidation process in the alloy was accelerated at 1150℃.The enhancement in durability and flexibility is primarily due to the dissolution of the brittle phase,along with the shape and dispersal of theγ′phase. 展开更多
关键词 GH4151 alloy annealing treatment residual stress precipitation evolution STRENGTH mechanical properties
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Exciting lattice oxygen of nickel–iron bi-metal alkoxide for efficient electrochemical oxygen evolution reaction 被引量:1
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作者 Saihang Zhang Senchuan Huang +8 位作者 Fengzhan Sun Yinghui Li Li Ren Hao Xu Zhao Li Yifei Liu Wei Li Lina Chong Jianxin Zou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期194-201,I0005,共9页
High efficiency,cost-effective and durable electrocatalysts are of pivotal importance in energy conversion and storage systems.The electro-oxidation of water to oxygen plays a crucial role in such energy conversion te... High efficiency,cost-effective and durable electrocatalysts are of pivotal importance in energy conversion and storage systems.The electro-oxidation of water to oxygen plays a crucial role in such energy conversion technologies.Herein,we report a robust method for the synthesis of a bimetallic alkoxide for efficient oxygen evolution reaction(OER)for alkaline electrolysis,which yields current density of 10 mA cm^(-2)at an overpotential of 215 mV in 0.1 M KOH electrolyte.The catalyst demonstrates an excellent durability for more than 540 h operation with negligible degradation in activity.Raman spectra revealed that the catalyst underwent structure reconstruction during OER,evolving into oxyhydroxide,which was the active site proceeding OER in alkaline electrolyte.In-situ synchrotron X-ray absorption experiment combined with density functional theory calculation suggests a lattice oxygen involved electrocatalytic reaction mechanism for the in-situ generated nickel–iron bimetal-oxyhydroxide catalyst.This mechanism together with the synergy between nickel and iron are responsible for the enhanced catalytic activity and durability.These findings provide promising strategies for the rational design of nonnoble metal OER catalysts. 展开更多
关键词 Oxygen evolution reaction Nickel-iron bi-metal alkoxide Lattice oxygen-mediated reaction mechanism Alkaline electrolysis ELECTROCATALYSTS
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Damage evolution of rock-encased-backfill structure under stepwise cyclic triaxial loading 被引量:1
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作者 Xin Yu Yuye Tan +4 位作者 Weidong Song John Kemeny Shengwen Qi Bowen Zheng Songfeng Guo 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期597-615,共19页
Rock-encased-backfill(RB)structures are common in underground mining,for example in the cut-andfill and stoping methods.To understand the effects of cyclic excavation and blasting activities on the damage of these RB ... Rock-encased-backfill(RB)structures are common in underground mining,for example in the cut-andfill and stoping methods.To understand the effects of cyclic excavation and blasting activities on the damage of these RB structures,a series of triaxial stepwise-increasing-amplitude cyclic loading experiments was conducted with cylindrical RB specimens(rock on outside,backfill on inside)with different volume fractions of rock(VF=0.48,0.61,0.73,and 0.84),confining pressures(0,6,9,and 12 MPa),and cyclic loading rates(200,300,400,and 500 N/s).The damage evolution and meso-crack formation during the cyclic tests were analyzed with results from stress-strain hysteresis loops,acoustic emission events,and post-failure X-ray 3D fracture morphology.The results showed significant differences between cyclic and monotonic loadings of RB specimens,particularly with regard to the generation of shear microcracks,the development of stress memory and strain hardening,and the contact forces and associated friction that develops along the rock-backfill interface.One important finding is that as a function of the number of cycles,the elastic strain increases linearly and the dissipated energy increases exponentially.Also,compared with monotonic loading,the cyclic strain hardening characteristics are more sensitive to rising confining pressures during the initial compaction stage.Another finding is that compared with monotonic loading,more shear microcracks are generated during every reloading stage,but these microcracks tend to be dispersed and lessen the likelihood of large shear fracture formation.The transition from elastic to plastic behavior varies depending on the parameters of each test(confinement,volume fraction,and cyclic rate),and an interesting finding was that the transformation to plastic behavior is significantly lower under the conditions of 0.73 rock volume fraction,400 N/s cyclic loading rate,and 9 MPa confinement.All the findings have important practical implications on the ability of backfill to support underground excavations. 展开更多
关键词 Rock and backfill Triaxial cyclic loading Volume fraction Damage evolution 3D visualization
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Origin and evolution of a new tetraploid mangrove species in an intertidal zone
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作者 Hui Feng Achyut Kumar Banerjee +9 位作者 Wuxia Guo Yang Yuan Fuyuan Duan Wei Lun Ng Xuming Zhao Yuting Liu Chunmei Li Ying Liu Linfeng Li Yelin Huang 《Plant Diversity》 SCIE CAS CSCD 2024年第4期476-490,共15页
Polyploidy is a major factor in the evolution of plants,yet we know little about the origin and evolution of polyploidy in intertidal species.This study aimed to identify the evolutionary transitions in three truemang... Polyploidy is a major factor in the evolution of plants,yet we know little about the origin and evolution of polyploidy in intertidal species.This study aimed to identify the evolutionary transitions in three truemangrove species of the genus Acanthus distributed in the Indo-West Pacific region.For this purpose,we took an integrative approach that combined data on morphology,cytology,climatic niche,phylogeny,and biogeography of 493 samples from 42 geographic sites.Our results show that the Acanthus ilicifolius lineage distributed east of the Thai-Malay Peninsula possesses a tetraploid karyotype,which is morphologically distinct from that of the lineage on the west side.The haplotype networks and phylogenetic trees for the chloroplast genome and eight nuclear genes reveal that the tetraploid species has two sub-genomes,one each from A.ilicifolius and A.ebracteatus,the paternal and maternal parents,respectively.Population structure analysis also supports the hybrid speciation history of the new tetraploid species.The two sub-genomes of the tetraploid species diverged from their diploid progenitors during the Pleistocene.Environmental niche models revealed that the tetraploid species not only occupied the near-entire niche space of the diploids,but also expanded into novel environments.Our findings suggest that A.ilicifolius species distributed on the east side of the Thai-Malay Peninsula should be regarded as a new species,A.tetraploideus,which originated from hybridization between A.ilicifolius and A.ebracteatus,followed by chromosome doubling.This is the first report of a true-mangrove allopolyploid species that can reproduce sexually and clonally reproduction,which explains the long-term adaptive potential of the species. 展开更多
关键词 Acanthus ALLOPOLYPLOID BIOGEOGRAPHY evolution HYBRIDIZATION POLYPLOIDY
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Comparison of Propofol and Fentanyl for Preventing Emergence Agitation Following Sevoflurane Anesthesia in Pediatric Patients: A Single-Center Study in Bangladesh
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作者 Md. Saiful Islam Khan Md. Abir Tazim Chowdhury +8 位作者 Farzana Fardousi Munama Magdum Md. Ahaduzzaman Taneem Mohammad Shamima Akter Suriya Akter Md. Saiful Islam Azad Md. Mozaffer Hossain M. Abdur Rahman 《Pharmacology & Pharmacy》 2024年第6期223-235,共13页
Background: Emergence agitation (EA) is a common phenomenon observed in pediatric patients following general anesthesia. This study aimed to assess the efficacy of propofol and fentanyl in preventing EA and to compare... Background: Emergence agitation (EA) is a common phenomenon observed in pediatric patients following general anesthesia. This study aimed to assess the efficacy of propofol and fentanyl in preventing EA and to compare their associated complications or side effects. Methods: This prospective randomized observational comparative study was conducted at Dhaka Medical College Hospital from July 2013 to June 2014. The study aimed to evaluate the effects of propofol and fentanyl on EA in children aged 18 to 72 months undergoing circumcision, herniotomy, and polypectomy operations. Ninety children were included in the study, with 45 in each group. Patients with psychological or neurological disorders were excluded. Various parameters including age, sex, weight, American Society of Anesthesiologists (ASA) class, duration of anesthesia, Saturation of Peripheral Oxygen (SPO2), heart rate (HR), respiratory rate (RR), Pediatric Anesthesia Emergence Delirium (PAED) score, duration of post-anesthesia care unit (PACU) stay, incidence of laryngospasm, nausea, vomiting, and rescue drug requirement were compared between the two groups. Results: Age, sex, weight, ASA class, and duration of anesthesia were comparable between the two groups. Perioperative SpO2 and HR were similar in both groups. However, the PAED score was significantly higher in the fentanyl group during all follow-ups except at 30 minutes postoperatively. The mean duration of PACU stay was significantly longer in the fentanyl group. Although the incidence of laryngospasm was higher in the fentanyl group, it was not statistically significant. Conversely, nausea or vomiting was significantly higher in the fentanyl group. The requirement for rescue drugs was significantly higher in the fentanyl group compared to the propofol group. Conclusion: Both propofol and fentanyl were effective in preventing emergence agitation in pediatric patients undergoing various surgical procedures under sevoflurane anesthesia. However, propofol demonstrated a better safety profile with fewer incidences of nausea, vomiting, and rescue drug requirements compared to fentanyl. 展开更多
关键词 emergence Agitation (EA) General Anesthesia PROPOFOL FENTANYL Pediatric Patients Pediatric Anesthesia emergence Delirium (PAED) Score BANGLADESH
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Microdynamic mechanical properties and fracture evolution mechanism of monzogabbro with a true triaxial multilevel disturbance method
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作者 Zhi Zheng Bin Deng +3 位作者 Hong Liu Wei Wang Shuling Huang Shaojun Li 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第3期385-411,共27页
The far-field microdynamic disturbance caused by the excavation of deep mineral resources and underground engineering can induce surrounding rock damage in high-stress conditions and even lead to disasters.However,the... The far-field microdynamic disturbance caused by the excavation of deep mineral resources and underground engineering can induce surrounding rock damage in high-stress conditions and even lead to disasters.However,the mechanical properties and damage/fracture evolution mechanisms of deep rock induced by microdynamic disturbance under three-dimensional stress states are unclear.Therefore,a true triaxial multilevel disturbance test method is proposed,which can completely simulate natural geostress,excavation stress redistribution(such as stress unloading,concentration and rotation),and subsequently the microdynamic disturbance triggering damaged rock failure.Based on a dynamic true triaxial test platform,true triaxial microdynamic disturbance tests under different frequency and amplitudes were carried out on monzogabbro.The results show that increasing amplitude or decreasing frequency diminishes the failure strength of monzogabbro.Deformation modulus gradually decreases during disturbance failure.As frequency and amplitude increase,the degradation rate of deformation modulus decreases slightly,disturbance dissipated energy increases significantly,and disturbance deformation anisotropy strengthens obviously.A damage model has been proposed to quantitatively characterize the disturbance-induced damage evolution at different frequency and amplitude under true triaxial stress.Before disturbance failure,the micro-tensile crack mechanism is dominant,and the micro-shear crack mechanism increases significantly at failure.With the increase of amplitude and frequency,the micro-shear crack mechanism increases.When approaching disturbance failure,the acoustic emission fractal dimension changes from a stable value to local large oscillation,and finally increases sharply to a high value at failure.Finally,the disturbance-induced failure mechanism of surrounding rock in deep engineering is clearly elucidated. 展开更多
关键词 True triaxial disturbance test Mechanical properties Fracture evolution mechanism Disturbance-induced damage evolution Failure mechanism and precursor
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Human lineage mutations regulate RNA-protein binding of conserved genes NTRK2 and ITPR1 involved in human evolution
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作者 Wenxiang Cai Weichen Song +2 位作者 Shunying Yu Min Zhao Guan Ning Lin 《General Psychiatry》 CSCD 2024年第3期375-387,共13页
Background The role of human lineage mutations(HLMs)in human evolution through post-transcriptional modification is unclear.Aims To investigate the contribution of HLMs to human evolution through post-transcriptional ... Background The role of human lineage mutations(HLMs)in human evolution through post-transcriptional modification is unclear.Aims To investigate the contribution of HLMs to human evolution through post-transcriptional modification.Methods We applied a deep learning model Seqweaver to predict how HLMs impact RNA-binding protein affinity.Results We found that only 0.27%of HLMs had significant impacts on RNA-binding proteins at the threshold of the top 1%of human common variations.These HLMs enriched in a set of conserved genes highly expressed in adult excitatory neurons and prenatal Purkinje neurons,and were involved in synapse organisation and the GTPase pathway.These genes also carried excess damaging coding mutations that caused neurodevelopmental disorders,ataxia and schizophrenia.Among these genes,NTRK2 and ITPR1 had the most aggregated evidence of functional importance,suggesting their essential roles in cognition and bipedalism.Conclusions Our findings suggest that a small subset of human-specific mutations have contributed to human speciation through impacts on post-transcriptional modification of critical brain-related genes. 展开更多
关键词 evolution CONSERVED HUMAN
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Acute Kidney Injury in the Nephrology Department of the Brazzaville University Hospital: Epidemiological, Clinical and Evolutionary Aspects
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作者 Daniel Tony Eyeni Sinomono Gael Honal Mahoungou +3 位作者 Eric Gabdzali Ngabé Audrey Missamou Mavi Bouloupy Richard Loumingou 《Open Journal of Nephrology》 2024年第2期196-215,共20页
Introduction: Acute kidney injury (AKI) is defined as a sudden and reversible deterioration in renal function. It is a life-threatening condition in hospitalized patients. Our objectives were to determine the prevalen... Introduction: Acute kidney injury (AKI) is defined as a sudden and reversible deterioration in renal function. It is a life-threatening condition in hospitalized patients. Our objectives were to determine the prevalence of AKI in a nephrology department, list the causes, describe the evolutionary profile and identify the factors associated with death. Patients and Methods: We reviewed the records of patients hospitalised between 1 January 2016 and 31 October 2020 in the nephrology department of Brazzaville University Hospital. We included patients aged at least 18 years whose discharge diagnosis included the item AKI. Study variables were socio-demographic data, clinical and paraclinical signs, stage and type of AKI, etiology and evolutionary profile. Results: Of the 1823 patients hospitalised, 244 (13.38%) were hospitalised for AKI. Of these, 60.2% were boys and 39.8% girls, with an average age of 47 19 years. The average consultation time was 10 6.5 days. AKI was stage 3 in 69.57% of cases. It was functional, organic and obstructive in the order of 55.28%, 36.02% and 8.69%. Dialysis was indicated in 62 patients (38.51%) and performed in 24 patients (14.9%). In-hospital mortality was 27.95%, with an average hospital stay of 9.6 5.8 days. Metabolic acidosis and anemia were the main causes of death in 14.28% and 4.35% of patients respectively. Factors associated with death were male sex, socioeconomic level, coma, indication for dialysis and absence of dialysis, with a p Conclusion: AKI is more common in young adult males. Mortality is relatively low. Improving prognosis requires early management and access to dialysis. 展开更多
关键词 AKI EPIDEMIOLOGY Diagnosis evolution BRAZZAVILLE
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Hydrochemical Characteristics and Evolution of Underground Brine in Lop Nur,Northwestern China
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作者 BO Ying LIU Chenglin +2 位作者 JIAO Pengcheng LU Fenglin ZHANG Hua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期786-800,共15页
Lop Nur is located at the eastmost end of the Tarim Basin in Xinjiang,Northwestern China.This study reviews the hydrochemical characteristics and evolution of underground brine in Lop Nur,based on analytical data from... Lop Nur is located at the eastmost end of the Tarim Basin in Xinjiang,Northwestern China.This study reviews the hydrochemical characteristics and evolution of underground brine in Lop Nur,based on analytical data from 429 water samples(mainly brine).It is found that in the NE-SW direction,from the periphery to the Luobei sub-depression,while the hydrochemical type varies from the sodium sulfate subtype(S)to the magnesium sulfate subtype(M),the corresponding brine in the phase diagram transfers from the thenardite phase(Then)area,through the bloedite phase(Blo),epsomite phase(Eps),picromerite phase(Picro),finally reaching the sylvite phase(Syl)area.As for the degree of evolution,the sequence is the periphery<Luobei horizontally and the overlying glauberite brine<the underlying clastic brine vertically.It is concluded that the oxygen and hydrogen isotopic compositions of the brine have evidently been affected through the effects of evaporation and altitude,as well as the changes in local water circulation in recent years.Boron and chloride isotopic compositions show that the glauberite brine is formed under more arid conditions than the clastic one.The strontium isotopic composition indicates that the Lop Nur brine primarily originates from surface water;however,deep recharge may also be involved in the evolution of the brine,according to previous noble gas studies.It is confirmed that the brine in Lop Nur has become enriched with potassium prior to halite precipitation over the full course of the salt lake's evolution.Based on chemical compositions of brine from drillhole LDK01 and previous lithological studies,the evolution of the salt lake can be divided into three stages and it is inferred that the brine in Lop Nur may have undergone at least two significant concentration-dilution periods. 展开更多
关键词 BRINE evolution ISOTOPE ENRICHMENT POTASSIUM Lop Nur
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Mpox and related poxviruses:A literature review of evolution,pathophysiology,and clinical manifestations
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作者 Priya Bhardwaj Swarnabha Sarkar Ritu Mishra 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第8期319-330,共12页
The recently re-emerged mpox(monkeypox)virus that causes mpox disease is a member of genus Orthopoxvirus and has unprecedentedly spread worldwide.Numerous studies have contributed to our understanding of its evolution... The recently re-emerged mpox(monkeypox)virus that causes mpox disease is a member of genus Orthopoxvirus and has unprecedentedly spread worldwide.Numerous studies have contributed to our understanding of its evolution,pathophysiology,and clinical manifestations.The current outbreak of the mpox virus depicts its novel route of transmission as a new variant.However,the exact reason for its transition from an epidemic to a pandemic remains unclear.Furthermore,other poxviruses such as vaccinia virus,variola virus,and cowpox virus,also belong to the same genus,Orthopoxvirus.In the present review,our objective was to summarize the evidence on evolution,pathophysiology,and clinical manifestations of mpox virus and its related poxviruses.The present review would aid in a better understanding of the current circulating mpox virus and its differences from other poxviruses.In addition,the shared genetic factors contributing to virulence in these Orthopoxvirus highlight their evolutionary connections and genetic similarities.While they exhibit differences in virulence,studying these genetic relationships is crucial for understanding their biology,pathogenicity,and the development of effective vaccines and antiviral therapeutics to curb mpox disease. 展开更多
关键词 evolution Mpox ORTHOPOXVIRUSES PATHOPHYSIOLOGY POXVIRUSES TRANSMISSION
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Enhancing Photocatalytic Hydrogen Evolution through Electronic Structure and Wettability Adjustment of ZnIn2S4/Bi2O3 S-Scheme Heterojunction
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作者 Linfeng Xiao Wanlu Ren +4 位作者 Shishi Shen Mengshan Chen Runhua Liao Yingtang Zhou Xibao Li 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第8期50-63,共14页
The production of renewable fuels through water splitting via photocatalytic hydrogen production holds significant promise.Nonetheless,the sluggish kinetics of hydrogen evolution and the inadequate water adsorption on... The production of renewable fuels through water splitting via photocatalytic hydrogen production holds significant promise.Nonetheless,the sluggish kinetics of hydrogen evolution and the inadequate water adsorption on photocatalysts present notable challenges.In this study,we have devised a straightforward hydrothermal method to synthesize Bi_(2)O_(3)(BO)derived from metal‐organic frameworks(MOFs),loaded with flower-like ZnIn_(2)S_(4)(ZIS).This approach substantially enhances water adsorption and surface catalytic reactions,resulting in a remarkable enhancement of photocatalytic activity.By employing triethanolamine(TEOA)as a sacrificial agent,the hydrogen evolution rate achieved with 15%(mass fraction)ZIS loading on BO reached an impressive value of 1610μmol∙h^(−1)∙g^(−1),marking a 6.34-fold increase compared to that observed for bare BO.Furthermore,through density functional theory(DFT)and ab initio molecular dynamics(AIMD)calculations,we have identified the reactions occurring at the ZIS/BO S-scheme heterojunction interface,including the identification of active sites for water adsorption and catalytic reactions.This study provides valuable insights into the development of high-performance composite photocatalytic materials with tailored electronic properties and wettability. 展开更多
关键词 S-scheme Hydrogen evolution WETTABILITY Photocatalysis Electronic structure
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Land-population-industry based village evolution and its influencing factors in the upper Tuojiang River
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作者 ZHAN Yunjun JI Yuxin +2 位作者 HUANG Jiejun MA Changying MA Chuanqi 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2790-2809,共20页
With economic development and urbanization in China,the rural settlements have experienced great change.To explore the evolution process of rural settlements in terms of land,population and industry can reveal the dev... With economic development and urbanization in China,the rural settlements have experienced great change.To explore the evolution process of rural settlements in terms of land,population and industry can reveal the development law of rural spatial distribution,population structure and industrial economy in different stages and regions.Studying the development status and evolution characteristics of villages in the upper Tuojiang River basin in Southwest China in the past 20 years are of significant value.The upper Tuojiang River basin includes the main types of terrain found in the Southwest region:mountainous,plains,and hills,exhibiting a certain typicality of geographical characteristics.This study took towns and townships at the town-level scale as the basic unit of research,and constructed an evaluation system for village evolution based on'land,population,and industry'.It employed Criteria Importance Through Inter-Criteria Correlation(CRITIC)analysis to examine the characteristics of village evolution in the area from 2000 to 2020,and used geographic detector analysis to identify the leading factors affecting village evolution.The results show that:(1)From 2000 to 2010,villages in the upper Tuojiang River basin experienced significant changes,and the pace of these transformations slowed from 2010 to 2020.(2)From a comprehensive perspective,from 2000 to 2020,villages in hilly areas show a decline,while villages in plain areas near the city center show a positive urbanization development.(3)Road accessibility and distance from the city center are the main factors that explain the spatial differentiation of village evolution degree in the study area.This study elucidates the spatiotemporal evolution characteristics of villages in the upper Tuojiang River basin and identifies the primary factors contributing to their changes,which will provide a reference for investigating the development of rural areas in different terrains of Southwest China. 展开更多
关键词 Village evolution LAND POPULATION Industry Geographic detector
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Identification of S-RNase genotype and analysis of its origin and evolutionary patterns in Malus plants
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作者 Zhao Liu Yuan Gao +10 位作者 Kun Wang Jianrong Feng Simiao Sun Xiang Lu Lin Wang Wen Tian Guangyi Wang Zichen Li Qingshan Li Lianwen Li Dajiang Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1205-1221,共17页
Identification of the S genotype of Malus plants will greatly promote the discovery of new genes,the cultivation and production of apple,the breeding of new varieties,and the origin and evolution of self-incompatibili... Identification of the S genotype of Malus plants will greatly promote the discovery of new genes,the cultivation and production of apple,the breeding of new varieties,and the origin and evolution of self-incompatibility in Malus plants.In this experiment,88 Malus germplasm resources,such as Aihuahong,Xishuhaitang,and Reguanzi,were used as materials.Seven gene-specific primer combinations were used in the genotype identification.PCR amplification using leaf DNA produced a single S-RNase gene fragment in all materials.The results revealed that 70 of the identified materials obtained a complete S-RNase genotype,while only one S-RNase gene was found in 18 of them.Through homology comparison and analysis,13 S-RNase genotypes were obtained:S_(1)S_(2)(Aihuahong,etc.),S_(1)S_(28)(Xixian Haitang,etc.),S_(1)S_(51)(Hebei Pingdinghaitang),S_(1)S_(3)(Xiangyangcun Daguo,etc.),S_(2)S_(3)(Zhaiyehaitang,etc.),S_(3)S_(51)(Xishan 1),S_(3)S_(28)(Huangselihaerde,etc.),S_(2)S_(28)(Honghaitang,etc.),S_(4)S_(28)(Bo 11),S_(7)S_(28)(Jiuquan Shaguo),S_(10)S_e(Dongchengguan 13),S_(10)S_(21)(Dongxiangjiao)and S_(3)S_(51)(Xiongyue Haitang).Simultaneously,the frequency of the S gene in the tested materials was analyzed.The findings revealed that different S genes had varying frequencies in Malus resources,as well as varying frequencies between intraspecific and interspecific.S_(3) had the highest frequency of 68.18%,followed by S_(1)(42.04%).In addition,the phylogenetic tree and origin evolution analysis revealed that the S gene differentiation was completed prior to the formation of various apple species,that cultivated species also evolved new S genes,and that the S_(50) gene is the oldest S allele in Malus plants.The S_(1),S_(29),and S_(33) genes in apple-cultivated species,on the other hand,may have originated in M.sieversii,M.hupehensis,and M.kansuensis,respectively.In addition to M.sieversii,M.kansuensis and M.sikkimensis may have also played a role in the origin and evolution of some Chinese apples. 展开更多
关键词 MALUS S-RNase genotype SELF-INCOMPATIBILITY origin and evolution
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