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Development of x-ray scintillator functioning also as an analyser grating used in grating-based x-ray differential phase contrast imaging 被引量:4
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作者 雷耀虎 刘鑫 +2 位作者 郭金川 赵志刚 牛憨笨 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期222-227,共6页
In order to push the grating-based phase contrast imaging system to be used in hospitM and laboratories, this paper designs and develops a novel structure of x-ray scintillator functioning also as an analyser grating,... In order to push the grating-based phase contrast imaging system to be used in hospitM and laboratories, this paper designs and develops a novel structure of x-ray scintillator functioning also as an analyser grating, which has been proposed for grating-based x-ray differential phase contrast imaging. According to this design, the scintillator should have a periodical structure in one dimension with the pitch equaling the period of self-image of the phase grating at the Talbot distance, where one half of the pitch is pixellated and is made of x-ray sensitive fluorescent material, such as CsI(T1), and the remaining part of the pitch is made of x-ray insensitive material, such as silicon. To realize the design, a deep pore array with a high aspect ratio and specially designed grating pattern are successfully manufactured on 5 inch silicon wafer by the photo-assisted electrochemical etching method. The related other problems, such as oxidation-caused geometrical distortion, the filling of CsI(T1) into deep pores and the removal of inside bubbles, have been overcome. Its pixel size, depth and grating pitch are 3 p.m^7.5 ~m, 150 p^m and 3 Ixm, respectively. The microstructure of the scintillator has been examined microscopically and macroscopically by scanning electron microscope and x-ray resolution chart testing, respectively. The preliminary measurements have shown that the proposed scintillator, also functioning as an analyser grating, has been successfully designed and developed. 展开更多
关键词 scintillator screen pore arrays oxidation CsI(T1) analyser grating
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An optical method for wavelength fine-selection in optical spectrum analysers 被引量:2
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作者 廖廷弟 邱怡申 徐惠贞 《Chinese Optics Letters》 SCIE EI CAS CSCD 2004年第9期552-554,共3页
This letter describes a novel optical method for wavelength fine-selection in the optical spectrum analysers (OSAs) for dense wavelength division multiplexing (DWDM) applications. The proposed new method employs a ... This letter describes a novel optical method for wavelength fine-selection in the optical spectrum analysers (OSAs) for dense wavelength division multiplexing (DWDM) applications. The proposed new method employs a 'refractive optical lever' system consisting of a rotating optical wedge prism. A new OSA system based on Littman-type monochromator is proposed and the wavelength selection accuracy and resolution of OSA that has included such an optical lever system have been improved by a factor of 20 to 100 depending on the wedge angle and offset orientation angle of the optical wedge prism. This proposed 'refractive optical lever' may also simplify the rotation mechanism of the mirror in the commercially available OSAs. 展开更多
关键词 An optical method for wavelength fine-selection in optical spectrum analysers DWDM OSA
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Weathering and accumulation of trace elements in the soils of the Porali Plain, Balochistan: repercussions in agriculture
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作者 Maria Kaleem Erum Bashir +2 位作者 Shahid Naseem Tahir Rafique Bushra Shahab 《Acta Geochimica》 EI CAS CSCD 2024年第2期214-234,共21页
This study is thefirst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by mu... This study is thefirst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by multi-variate analysis based on geochemical data.The outcomes of this study are expected to help farmers in soil manage-ment and selecting suitable crops for the region.Twenty-five soil samples were collected,mainly from the arable land of the Porali Plain.After drying and coning-quarter-ing,soil samples were analyzed for major and trace ele-ments using the XRF technique;sieving and hydrometric methods were employed for granulometric analysis.Esti-mated data were analyzed using Excel,SPSS,and Surfer software to calculate various indices,correlation matrix,and spatial distribution.The granulometric analysis showed that 76%of the samples belonged to loam types of soil,12%to sand type,and 8%to silt type.Weathering indices:CIA,CIW,PIA,PWI,WIP,CIX,and ICV were calculated to infer the level of alteration.These indices reflect mod-erate to intense weathering;supported by K_(2)O/AI_(2)O_(3),Rb/K_(2)O,Rb/Ti,and Rb/Sr ratios.Assessment of the geo-ac-cumulation and Nemerow Pollution indices pinpoint rela-tively high concentrations of Pb,Ni,and Cr concentration in the soils.The correlation matrix and Principal Compo-nent Analysis show that the soil in this study area is mainly derived from the weathering of igneous rocks of Bela Ophiolite(Cretaceous age)and Jurassic sedimentary rocks of Mor Range having SEDEX/MVT type mineralization.Weathering may result in the undesirable accumulation of certain trace elements which adversely affects crops. 展开更多
关键词 Weathering indices Pollution indices ACCUMULATION Repercussions Trace elements Multivariate analyses Porali Plain BALOCHISTAN
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Encroachment drives facilitation at alpine shrublines
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作者 Yafeng Wang Eryuan Liang J.Julio Camarero 《Forest Ecosystems》 SCIE CSCD 2024年第1期62-72,共11页
Ongoing encroachment is driving recent alpine shrubline dynamics globally,but the role of shrub-shrub interactions in shaping shrublines and their relationships with stem density changes remain poorly understood.Here,... Ongoing encroachment is driving recent alpine shrubline dynamics globally,but the role of shrub-shrub interactions in shaping shrublines and their relationships with stem density changes remain poorly understood.Here,the size and age of shrubs from 26 Salix shrubline populations along a 900-km latitudinal gradient(30°-38°N)were measured and mapped across the eastern Tibetan Plateau.Point pattern analyses were used to quantify the spatial distribution patterns of juveniles and adults,and to assess spatial associations between them.Mean intensity of univariate and bivariate spatial patterns was related to biotic and abiotic variables.Bivariate mark correlation functions with a quantitative mark(shrub height,basal stem diameter,crown width)were also employed to investigate the spatial relationships between shrub traits of juveniles and adults.Structural equation models were used to explore the relationships among conspecific interactions,patterns,shrub traits and recruitment dynamics under climate change.Most shrublines showed clustered patterns,suggesting the existence of conspecific facilitation.Clustered patterns of juveniles and conspecific interactions(potentially facilitation)tended to intensify with increasing soil moisture stress.Summer warming before 2010 triggered positive effects on population interactions and spatial patterns via increased shrub recruitment.However,summer warming after2010 triggered negative effects on interactions through reduced shrub recruitment.Therefore,shrub recruitment shifts under rapid climate change could impact spatial patterns,alter conspecific interactions and modify the direction and degree of shrublines responses to climate.These changes would have profound implications for the stability of alpine woody ecosystems. 展开更多
关键词 Alpine shrubline Positive interactions FACILITATION Spatial clustering Point pattern analyses
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Numerical investigation of hydro-morphodynamic characteristics of a cascading failure of landslide dams
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作者 ZHONG Qiming CHEN Lingchun +3 位作者 MEI Shengyao SHAN Yibo WU Hao ZHAO Kunpeng 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1868-1885,共18页
A cascading failure of landslide dams caused by strong earthquakes or torrential rains in mountainous river valleys can pose great threats to people’s lives,properties,and infrastructures.In this study,based on the t... A cascading failure of landslide dams caused by strong earthquakes or torrential rains in mountainous river valleys can pose great threats to people’s lives,properties,and infrastructures.In this study,based on the three-dimensional Reynoldsaveraged Navier-Stokes equations(RANS),the renormalization group(RNG)k-εturbulence model,suspended and bed load transport equations,and the instability discriminant formula of dam breach side slope,and the explicit finite volume method(FVM),a detailed numerical simulation model for calculating the hydro-morphodynamic characteristics of cascading dam breach process has been developed.The developed numerical model can simulate the breach hydrograph and the dam breach morphology evolution during the cascading failure process of landslide dams.A model test of the breaches of two cascading landslide dams has been used as the validation case.The comparison of the calculated and measured results indicates that the breach hydrograph and the breach morphology evolution process of the upstream and downstream dams are generally consistent with each other,and the relative errors of the key breaching parameters,i.e.,the peak breach flow and the time to peak of each dam,are less than±5%.Further,the comparison of the breach hydrographs of the upstream and downstream dams shows that there is an amplification effect of the breach flood on the cascading landslide dam failures.Three key parameters,i.e.,the distance between the upstream and the downstream dams,the river channel slope,and the downstream dam height,have been used to study the flood amplification effect.The parameter sensitivity analyses show that the peak breach flow at the downstream dam decreases with increasing distance between the upstream and the downstream dams,and the downstream dam height.Further,the peak breach flow at the downstream dam first increases and then decreases with steepening of the river channel slope.When the flood caused by the upstream dam failure flows to the downstream dam,it can produce a surge wave that overtops and erodes the dam crest,resulting in a lowering of the dam crest elevation.This has an impact on the failure occurrence time and the peak breach flow of the downstream dam.The influence of the surge wave on the downstream dam failure process is related to the volume of water that overtops the dam crest and the erosion characteristics of dam material.Moreover,the cascading failure case of the Xiaogangjian and Lower Xiaogangjian landslide dams has also been used as the representative case for validating the model.In comparisons of the calculated and measured breach hydrographs and final breach morphologies,the relative errors of the key dam breaching parameters are all within±10%,which verify the rationality of the model is applicable to real-world cases.Overall,the numerical model developed in this study can provide important technical support for the risk assessment and emergency treatment of failures of cascading landslide dams. 展开更多
关键词 Cascading landslide dams Cascading dam failure process Detailed numerical simulation model Flood amplification effect Parameter sensitivity analyses
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Causal roles of gut microbiota in cholangiocarcinoma etiology suggested by genetic study
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作者 Zhi-Tao Chen Chen-Chen Ding +3 位作者 Kai-Lei Chen Yang-Jun Gu Chi-Cheng Lu Qi-Yong Li 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1319-1333,共15页
BACKGROUND Cholangiocarcinoma(CCA)is a highly malignant biliary tract cancer with poor prognosis.Previous studies have implicated the gut microbiota in CCA,but evidence for causal mechanisms is lacking.AIM To investig... BACKGROUND Cholangiocarcinoma(CCA)is a highly malignant biliary tract cancer with poor prognosis.Previous studies have implicated the gut microbiota in CCA,but evidence for causal mechanisms is lacking.AIM To investigate the causal relationship between gut microbiota and CCA risk.METHODS We performed a two-sample mendelian randomization study to evaluate potential causal associations between gut microbiota and CCA risk using genome-wide association study summary statistics for 196 gut microbial taxa and CCA.Genetic variants were used as instrumental variables.Multiple sensitivity analyses assessed result robustness.RESULTS Fifteen gut microbial taxa showed significant causal associations with CCA risk.Higher genetically predicted abundance of genus Eubacteriumnodatum group,genus Ruminococcustorques group,genus Coprococcus,genus Dorea,and phylum Actinobacteria were associated with reduced risk of gallbladder cancer and extrahepatic CCA.Increased intrahepatic CCA risk was associated with higher abundance of family Veillonellaceae,genus Alistipes,order Enterobacteriales,and phylum Firmicutes.Protective effects against CCA were suggested for genus Collinsella,genus Eisenbergiella,genus Anaerostipes,genus Paraprevotella,genus Parasutterella,and phylum Verrucomicrobia.Sensitivity analyses indicated these findings were reliable without pleiotropy.CONCLUSION This pioneering study provides novel evidence that specific gut microbiota may play causal roles in CCA risk.Further experimental validation of these candidate microbes is warranted to consolidate causality and mechanisms. 展开更多
关键词 CHOLANGIOCARCINOMA Mendelian randomization Gut microbiota Instrumental variables Sensitivity analyses
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Design,preparation,application of advanced array structured materials and their action mechanism analyses for high performance lithium-sulfur batteries
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作者 Nanping Deng Xiaofan Feng +7 位作者 Yongbing Jin Zhaozhao Peng Yang Feng Ying Tian Yong Liu Lu Gao Weimin Kang Bowen Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期266-303,I0007,共39页
Lithium-sulfur battery(LSB)has brought much attention and concern because of high theoretical specific capacity and energy density as one of main competitors for next-generation energy storage systems.The widely comme... Lithium-sulfur battery(LSB)has brought much attention and concern because of high theoretical specific capacity and energy density as one of main competitors for next-generation energy storage systems.The widely commercial application and development of LSB is mainly hindered by serious“shuttle effect”of lithium polysulfides(Li PSs),slow reaction kinetics,notorious lithium dendrites,etc.In various structures of LSB materials,array structured materials,possessing the composition of ordered micro units with the same or similar characteristics of each unit,present excellent application potential for various secondary cells due to some merits such as immobilization of active substances,high specific surface area,appropriate pore sizes,easy modification of functional material surface,accommodated huge volume change,enough facilitated transportation for electrons/lithium ions,and special functional groups strongly adsorbing Li PSs.Thus many novel array structured materials are applied to battery for tackling thorny problems mentioned above.In this review,recent progresses and developments on array structured materials applied in LSBs including preparation ways,collaborative structural designs based on array structures,and action mechanism analyses in improving electrochemical performance and safety are summarized.Meanwhile,we also have detailed discussion for array structured materials in LSBs and constructed the structure-function relationships between array structured materials and battery performances.Lastly,some directions and prospects about preparation ways,functional modifications,and practical applications of array structured materials in LSBs are generalized.We hope the review can attract more researchers'attention and bring more studying on array structured materials for other secondary batteries including LSB. 展开更多
关键词 Array structured materials Preparation methods and structural designs Action mechanism analyses Advanced Li-S batteries Excellent electrochemical performances and safety
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Self-assembly of differentiated dental pulp stem cells facilitates spheroid human dental organoid formation and prevascularization
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作者 Fei Liu Jing Xiao +4 位作者 Lei-Hui Chen Yu-Yue Pan Jun-Zhang Tian Zhi-Ren Zhang Xiao-Chun Bai 《World Journal of Stem Cells》 SCIE 2024年第3期287-304,共18页
BACKGROUND The self-assembly of solid organs from stem cells has the potential to greatly expand the applicability of regenerative medicine.Stem cells can self-organise into microsized organ units,partially modelling ... BACKGROUND The self-assembly of solid organs from stem cells has the potential to greatly expand the applicability of regenerative medicine.Stem cells can self-organise into microsized organ units,partially modelling tissue function and regeneration.Dental pulp organoids have been used to recapitulate the processes of tooth development and related diseases.However,the lack of vasculature limits the utility of dental pulp organoids.AIM To improve survival and aid in recovery after stem cell transplantation,we demonstrated the three-dimensional(3D)self-assembly of adult stem cell-human dental pulp stem cells(hDPSCs)and endothelial cells(ECs)into a novel type of spheroid-shaped dental pulp organoid in vitro under hypoxia and conditioned medium(CM).METHODS During culture,primary hDPSCs were induced to differentiate into ECs by exposing them to a hypoxic environment and CM.The hypoxic pretreated hDPSCs were then mixed with ECs at specific ratios and conditioned in a 3D environment to produce prevascularized dental pulp organoids.The biological characteristics of the organoids were analysed,and the regulatory pathways associated with angiogenesis were studied.RESULTS The combination of these two agents resulted in prevascularized human dental pulp organoids(Vorganoids)that more closely resembled dental pulp tissue in terms of morphology and function.Single-cell RNA sequencing of dental pulp tissue and RNA sequencing of Vorganoids were integrated to analyse key regulatory pathways associated with angiogenesis.The biomarkers forkhead box protein O1 and fibroblast growth factor 2 were identified to be involved in the regulation of Vorganoids.CONCLUSION In this innovative study,we effectively established an in vitro model of Vorganoids and used it to elucidate new mechanisms of angiogenesis during regeneration,facilitating the development of clinical treatment strategies. 展开更多
关键词 Human dental pulp stem cells Prevascularized organoids Integrated analyses ANGIOGENESIS Forkhead box protein O1
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In silico prospective analysis of the medicinal plants activity on the CagA oncoprotein from Helicobacter pylori
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作者 Rafaela Viana Vieira Gabrielle Caroline Peiter +2 位作者 Fabrício Freire de Melo Ana Carla Zarpelon-Schutz Kádima Nayara Teixeira 《World Journal of Clinical Oncology》 2024年第5期653-663,共11页
BACKGROUND Colonization with Helicobacter pylori(H.pylori)has a strong correlation with gastric cancer,and the virulence factor CagA is implicated in carcinogenesis.Studies have been conducted using medicinal plants w... BACKGROUND Colonization with Helicobacter pylori(H.pylori)has a strong correlation with gastric cancer,and the virulence factor CagA is implicated in carcinogenesis.Studies have been conducted using medicinal plants with the aim of eliminating the pathogen;however,the possibility of blocking H.pylori-induced cell differentiation to prevent the onset and/or progression of tumors has not been addressed.This type of study is expensive and time-consuming,requiring in vitro and/or in vivo tests,which can be solved using bioinformatics.Therefore,prospective computational analyses were conducted to assess the feasibility of interaction between phenolic compounds from medicinal plants and the CagA oncoprotein.AIM To perform a computational prospecting of the interactions between phenolic compounds from medicinal plants and the CagA oncoprotein of H.pylori.METHODS In this in silico study,the structures of the phenolic compounds(ligands)kaempferol,myricetin,quercetin,ponciretin(flavonoids),and chlorogenic acid(phenolic acid)were selected from the PubChem database.These phenolic compounds were chosen based on previous studies that suggested medicinal plants as non-drug treatments to eliminate H.pylori infection.The three-dimensional structure model of the CagA oncoprotein of H.pylori(receptor)was obtained through molecular modeling using computational tools from the I-Tasser platform,employing the threading methodology.The primary sequence of CagA was sourced from GenBank(BAK52797.1).A screening was conducted to identify binding sites in the structure of the CagA oncoprotein that could potentially interact with the ligands,utilizing the GRaSP online platform.Both the ligands and receptor were prepared for molecular docking using AutoDock Tools 4(ADT)software,and the simulations were carried out using a combination of ADT and AutoDock Vina v.1.2.0 software.Two sets of simulations were performed:One involving the central region of CagA with phenolic compounds,and another involving the carboxy-terminus region of CagA with phenolic compounds.The receptor-ligand complexes were then analyzed using PyMol and BIOVIA Discovery Studio software.RESULTS The structure model obtained for the CagA oncoprotein exhibited high quality(C-score=0.09)and was validated using parameters from the MolProbity platform.The GRaSP online platform identified 24 residues(phenylalanine and leucine)as potential binding sites on the CagA oncoprotein.Molecular docking simulations were conducted with the three-dimensional model of the CagA oncoprotein.No complexes were observed in the simulations between the carboxy-terminus region of CagA and the phenolic compounds;however,all phenolic compounds interacted with the central region of the oncoprotein.Phenolic compounds and CagA exhibited significant affinity energy(-7.9 to-9.1 kcal/mol):CagA/kaempferol formed 28 chemical bonds,CagA/myricetin formed 18 chemical bonds,CagA/quercetin formed 16 chemical bonds,CagA/ponciretin formed 13 chemical bonds,and CagA/chlorogenic acid formed 17 chemical bonds.Although none of the phenolic compounds directly bound to the amino acid residues of the K-Xn-R-X-R membrane binding motif,all of them bound to residues,mostly positively or negatively charged,located near this region.CONCLUSION In silico,the tested phenolic compounds formed stable complexes with CagA.Therefore,they could be tested in vitro and/or in vivo to validate the findings,and to assess interference in CagA/cellular target interactions and in the oncogenic differentiation of gastric cells. 展开更多
关键词 CagA oncoprotein Phenolic compounds Helicobacter pylori In silico analyses Medicinal plants Prospective analysis
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3-Dimensional Kinematic Comparison of Arm Movements between an Individual with NGLY1 Deficiency and a Neurotypical Individual
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作者 Charles S. Layne Christopher A. Malaya +6 位作者 Brock Futrell Dacia Martinez Diaz Christian Alfaro Hannah E. Gustafson Subhalakshmi Chandrasekaran Rhea M. Phatak Bernhard Suter 《Case Reports in Clinical Medicine》 2024年第4期122-146,共25页
NGLY1 Deficiency is an ultra-rare autosomal recessively inherited disorder. Characteristic symptoms include among others, developmental delays, movement disorders, liver function abnormalities, seizures, and problems ... NGLY1 Deficiency is an ultra-rare autosomal recessively inherited disorder. Characteristic symptoms include among others, developmental delays, movement disorders, liver function abnormalities, seizures, and problems with tear formation. Movements are hyperkinetic and may include dysmetric, choreo-athetoid, myoclonic and dystonic movement elements. To date, there have been no quantitative reports describing arm movements of individuals with NGLY1 Deficiency. This report provides quantitative information about a series of arm movements performed by an individual with NGLY1 Deficiency and an aged-matched neurotypical participant. Three categories of arm movements were tested: 1) open ended reaches without specific end point targets;2) goal-directed reaches that included grasping an object;3) picking up small objects from a table placed in front of the participants. Arm movement kinematics were obtained with a camera-based motion analysis system and “initiation” and “maintenance” phases were identified for each movement. The combination of the two phases was labeled as a “complete” movement. Three-dimensional analysis techniques were used to quantify the movements and included hand trajectory pathlength, joint motion area, as well as hand trajectory and joint jerk cost. These techniques were required to fully characterize the movements because the NGLY1 individual was unable to perform movements only in the primary plane of progression instead producing motion across all three planes of movement. The individual with NGLY1 Deficiency was unable to pick up objects from a table or effectively complete movements requiring crossing the midline. The successfully completed movements were analyzed using the above techniques and the results of the two participants were compared statistically. Almost all comparisons revealed significant differences between the two participants, with a notable exception of the 3D initiation area as a percentage of the complete movement. The statistical tests of these measures revealed no significant differences between the two participants, possibly suggesting a common underlying motor control strategy. The 3D techniques used in this report effectively characterized arm movements of an individual with NGLY1 deficiency and can be used to provide information to evaluate the effectiveness of genetic, pharmacological, or physical rehabilitation therapies. 展开更多
关键词 NGLY1 Deficiency Developmental Disorders KINEMATICS 3 Dimensional Analyses
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Analysis of postoperative ocular surface changes and intervention effect after pars plana vitrectomy in meibomian gland dysfunction dry eye patients
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作者 Bo-Shi Liu Jiao-Ting Wei +5 位作者 Ze-Tong Nie Meng Yang Shao-Fang Pang Wen-Bo Li Xiao-Rong Li Bo-Jie Hu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第5期721-729,共9页
AIM:To observe ocular surface changes after phacovitrectomy in patients with mild to moderate meibomian gland dysfunction(MGD)-type dry eye and track clinical treatment response using a Keratograph 5M and a Lipi View ... AIM:To observe ocular surface changes after phacovitrectomy in patients with mild to moderate meibomian gland dysfunction(MGD)-type dry eye and track clinical treatment response using a Keratograph 5M and a Lipi View interferometer.METHODS:Forty cases were randomized into control group A and treatment group B;the latter received meibomian gland treatment 3d before phacovitrectomy and sodium hyaluronate before and after surgery.The average non-invasive tear film break-up time(NITBUTav),first noninvasive tear film break-up time(NITBUTf),non-invasive measured tear meniscus height(NTMH),meibomian gland loss(MGL),lipid layer thickness(LLT)and partial blink rate(PBR)were measured preoperatively and 1wk,1 and 3mo postoperatively.RESULTS:The NITBUTav values of group A at 1wk(4.38±0.47),1mo(6.76±0.70),and 3mo(7.25±0.68)were significantly lower than those of group B(7.45±0.78,10.46±0.97,and 11.31±0.89;P=0.002,0.004,and 0.001,respectively).The NTMH values of group B at 1wk(0.20±0.01)and 1mo(0.22±0.01)were markedly higher than those of group A(0.15±0.01 and 0.15±0.01;P=0.008 and P<0.001,respectively);however,there was no difference at 3mo.The LLT of group B at 3mo[91.5(76.25-100.00)]significantly exceeded that of group A[65.00(54.50-91.25),P=0.017].No obvious intergroup difference was found in MGL or PBR(P>0.05).CONCLUSION:Mild to moderate MGD dry eye worsens in the short term after phacovitrectomy.Preoperative cleaning,hot compresses,and meibomian gland massage as well as preoperative and postoperative sodium hyaluronate promote the rapid recovery of tear film stability. 展开更多
关键词 meibomian gland dysfunction dry eye non-invasive ocular surface analyser pars plana vitrectomy meibomian gland massage
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Multiple Data Sources Reveal a New Asian Leaf Litter Toad of Leptobrachella Smith, 1925 (Anura, Megophryidae) from Southwestern China 被引量:1
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作者 Shengchao SHI Tuo SHEN +2 位作者 Xin WANG Jianping JIANG Bin WANG 《Asian Herpetological Research》 SCIE CSCD 2023年第1期65-94,I0004,共31页
A new species of Leptobrachella is described from Sichuan Province and Chongqing Municipality,China.Molecular phylogenetic analyses based on mitochondrial and nuclear gene sequences indicated that the new species is g... A new species of Leptobrachella is described from Sichuan Province and Chongqing Municipality,China.Molecular phylogenetic analyses based on mitochondrial and nuclear gene sequences indicated that the new species is genetically divergent from its congeners.It could be identified from its congeners by a combination of followings characters:body size of male 29.1-34.1 mm(n=14),female 34.1-34.9 mm(n=4);dorsal skin rough with large tubercles in size of humeral glands,without conical spines;fringes on toes narrow;ventral body basically floral white with deep grey pigments all over;dorsal body deep greyish brown with smoky black markings;iris gold above,gradually silver bellow;tibia-tarsal articulation reaches the level of the middle of the eye when leg being stretched forward;the main call type with dominant frequency4.08 ± 0.16 kHz(14.1-14.9℃),call duration 170.35± 15.19ms,the number of pulses for the first note in a call 3.50±0.89,and the number of pulses for the second note in a call 5.08±0.77. 展开更多
关键词 BIOACOUSTICS MEGOPHRYIDAE molecular phylogenetic analyses morphology new species
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Phase separation-hydrogen etching-derived Cu-decorated Cu-Mn bimetallic oxides with oxygen vacancies boosting superior sodium-ion storage kinetics 被引量:1
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作者 Lin Yan Lingshuo Zong +6 位作者 Qi Sun Junpeng Guo Zhenyang Yu Zhijun Qiao Jiuhui Han Zhenyu Cui Jianli Kang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期163-173,I0005,共12页
Understanding the crystal phase evolution of bimetallic oxide anodes is the main concern to profoundly reveal the conversion reaction kinetics and sodium-ion storage mechanisms.Herein,an integrated selfsupporting anod... Understanding the crystal phase evolution of bimetallic oxide anodes is the main concern to profoundly reveal the conversion reaction kinetics and sodium-ion storage mechanisms.Herein,an integrated selfsupporting anode of the Cu-decorated Cu-Mn bimetallic oxides with oxygen vacancies(Ov-BMO-Cu)are in-situ generated by phase separation and hydrogen etching using nanoporous Cu-Mn alloy as selfsacrificial templates.On this basis,we have elucidated the relationship between the phase evolution,oxygen vacancies and sodium-ion storage mechanisms,further demonstrating the evolution of oxygen vacancies and the inhibition effect of manganese oxides as an“anchor”on grain aggregation of copper oxides.The kinetic analyses confirm that the expanded lattice space and increased oxygen vacancies of cycled Ov-BMO-Cu synergistically guarantee effective sodium-ion diffusion and storage mechanisms.Therefore,the Ov-BMO-Cu electrode exhibits higher reversible capacities of 4.04 mA h cm^(-2)at 0.2 mA cm^(-2)after 100 cycles and 2.20 m A h cm^(-2)at 1.0 mA cm^(-2)after 500 cycles.Besides,the presodiated Ov-BMO-Cu anode delivers a considerable reversible capacity of 0.79 m A h cm^(-2)at 1.0 mA cm^(-2)after 60 cycles in full cells with Na_(3)V_(2)(PO_(4))_(3)cathode,confirming its outstanding practicality.Thus,this work is expected to provide enlightenment for designing high-capacity bimetallic oxide anodes. 展开更多
关键词 Sodium-ion storage mechanism Bimetallic oxide anode material Crystal phase evolution Oxygen vacancies Kinetic analyses
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Phylogenetic and epidemiological characteristics of H9N2 avian influenza viruses in Shandong Province, China from 2019 to 2021
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作者 ZHAO Yi-ran ZHAO Yu-zhong +7 位作者 LIU Si-dang XIAO Yi-hong LI Ning LIU Kui-hao MENG Fan-liang ZHAO Jun LIU Meng-da LI Bao-quan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第3期881-896,共16页
H9N2 avian influenza virus(AIV) has widely circulated in poultry worldwide and sporadic infections in humans and mammals. During our surveillance of chicken from 2019 to 2021 in Shandong Province, China, we isolated 1... H9N2 avian influenza virus(AIV) has widely circulated in poultry worldwide and sporadic infections in humans and mammals. During our surveillance of chicken from 2019 to 2021 in Shandong Province, China, we isolated 11 H9N2AIVs. Phylogenetic analyses showed that the eight gene segments of the 11 isolates were closely related to several sublineages of Eurasian lineage: BJ/94-like clades(HA and NA genes), G1-like clades(PB2 and M genes), and SH/F/98-like clades(PB1, PA, NP and NS genes). The isolates showed mutation sites that preferentially bind to humanlike receptors(HA) and mammalian fitness sites(PB2, PB1 and PA), as well as mutations in antigen and drug resistance sites. Moreover, studies with mice revealed four isolates with varying levels of pathogenicity. The average antibody titer of the H9N2 AIVs was 8.60 log2. Based on our results, the epidemiological surveillance of H9N2 AIVs should be strengthened. 展开更多
关键词 influenza virus phylogenetic analyses mutation sites PATHOGENICITY antibody titer epidemiological surveillance
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The need to develop tailored tools for improving the quality of thematic bibliometric analyses: Evidence from papers published in Sustainability and Scientometrics
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作者 Alvaro Cabezas-Clavijo Yusnelkis Milanés-Guisado +1 位作者 Ruben Alba-Ruiz Ángel MDelgado-Vázquez 《Journal of Data and Information Science》 CSCD 2023年第4期10-35,共26页
Purpose: The aim of this article is to explore up to seven parameters related to the methodological quality and reproducibility of thematic bibliometric research published in the two most productive journals in biblio... Purpose: The aim of this article is to explore up to seven parameters related to the methodological quality and reproducibility of thematic bibliometric research published in the two most productive journals in bibliometrics, Sustainability(a journal outside the discipline) and Scientometrics, the flagship journal in the field.Design/methodology/approach: The study identifies the need for developing tailored tools for improving the quality of thematic bibliometric analyses, and presents a framework that can guide the development of such tools. A total of 508 papers are analysed, 77% of Sustainability, and 23% published in Scientometrics, for the 2019-2021 period.Findings: An average of 2.6 shortcomings per paper was found for the whole sample, with an almost identical number of flaws in both journals. Sustainability has more flaws than Scientometrics in four of the seven parameters studied, while Scientometrics has more shortcomings in the remaining three variables.Research limitations: The first limitation of this work is that it is a study of two scientific journals, so the results cannot be directly extrapolated to the set of thematic bibliometric analyses published in journals from all fields.Practical implications: We propose the adoption of protocols, guidelines, and other similar tools, adapted to bibliometric practice, which could increase the thoroughness, transparency, and reproducibility of this type of research.Originality/value: These results show considerable room for improvement in terms of the adequate use and breakdown of methodological procedures in thematic bibliometric research, both in journals in the Information Science area and journals outside the discipline. 展开更多
关键词 Thematic bibliometric analyses SUSTAINABILITY SCIENTOMETRICS Reproducibility Methodological quality
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From landslide characterization to nature reserve management:The“Scialimata Grande di Torre Alfina”landslide Geosite(Central Apennines,Italy)
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作者 Gianluca TRONTI Francesca VERGARI +4 位作者 Irene Maria BOLLATI Filippo BELISARIO Maurizio DELMONTE Manuela PELFINI Paola FREDI 《Journal of Mountain Science》 SCIE CSCD 2023年第3期585-606,共22页
Italy is characterized by widespread geomorphological instability,among which landslides leave impressive marks on the landscape.Nevertheless,landslide bodies may represent key sites for thematic and educational itine... Italy is characterized by widespread geomorphological instability,among which landslides leave impressive marks on the landscape.Nevertheless,landslide bodies may represent key sites for thematic and educational itineraries,especially in protected areas,where their management becomes an important issue.Our study focuses on the"Monte Rufeno Nature Reserve"(Central Apennines,Italy),where iconic landslides are present.Here,the"Scialimata Grande di Torre Alfina"landslide(SGTA)is listed in the regional Geosite database.This work aims to propose a multiscale procedure for landslide analysis,in terms of both hazard sources but also educational and geoheritage enhancement opportunities in natural reserves.After performing a Landslide Susceptibility conditional Analysis(LSA)for the reserve territory,attention was focused on the SGTA,to define properly its features and morphodynamics.A multi-disciplinary approach was adopted,by applying both remote sensing(UAV structure from motion,Photointerpretation)and field survey(geomorphological and GPS monitoring).From the LSA,based on drainage density,curvature,and slope triggering factors,the road and trail susceptibility maps were derived,as base tools for future risk assessments and trail paths management within the reserve.At the SGTA scale,the monitoring showed a displacement of up to 23 m during the time interval between 2015 and 2018.The landslide dynamics seem to be driven by alternating dry and extremely wet periods;moreover,leaks from the aqueduct in the detachment area and piping effects through clays may have also decreased the substrate cohesion.The SGTA complex influence on the Paglia River valley geometry was also hypothesized,underlining the action of landslide through different spatial scales(on-site and off-site)and on different environment features(sediment connectivity,hydrology).Finally,the SGTA appears highly representative of the geomorphic dynamics within the Nature Reserve(i.e.,scientific value)and it could be classified as an active geosite.Since the site was featured by a tourist trail,adequate management strategies must be adopted,considering the educational value and safety issues. 展开更多
关键词 LANDSLIDES GEOHERITAGE Geosites Nature reserves management UAV structure from motion Landslides conditional analyses
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Phylogeography and diversification of Oriental weaverbirds(Ploceus spp.):A gradual increase of eurytopy
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作者 Abdul Razaq Giovanni Forcina +5 位作者 Urban Olsson Qian Tang Robert Tizard Naing Lin Nila Pwint Aleem Ahmed Khan 《Avian Research》 SCIE CSCD 2023年第4期511-522,共12页
Weaverbirds are a speciose group of colorful passerines inhabiting the Old World Tropics.Nevertheless,the Oriental weaverbirds(Ploceus spp.),widespread across southern Asia,are much less diverse and restricted to a fe... Weaverbirds are a speciose group of colorful passerines inhabiting the Old World Tropics.Nevertheless,the Oriental weaverbirds(Ploceus spp.),widespread across southern Asia,are much less diverse and restricted to a few ecological niches compared to their African counterpart.To investigate their phylogeography,we retrieved 101 samples of Baya Weaver(P.philippinus),Streaked Weaver(P.manyar),Black-Throated Weaver(P.benghalensis)and Asian Golden Weaver(P.hypoxanthus)along with GenBank sequences of Finn's Weaver(P.megarhynchus).We reconstructed the first molecular phylogeny based on a dataset consisting of both mitochondrial and nuclear genes,dating the most recent common ancestor of Oriental Ploceus to~11 mya.Subsequent speciation appears to have been a combination of divergence within the Indian subcontinent and dispersal across a barrier situated between the Indian subcontinent and the Indochinese region,which provided habitats with a varying degree of isolations and ultimately promoted divergences in allopatry.Two descendants of the earliest nodes,P.megarhynchus and P.hypoxanthus,are both rare and local,often found near large river systems,which perhaps reflects niche conservatism and a lack of adaptive potential.The three smaller species are all widespread,common and less habitat specific.The most recent divergence,between western and eastern P.philippinus populations,is supported by both phylogenetic and morphological evidence,pointing toward limited gene flow between them.However,a zone of intergradation may exist in Myanmar and Brahmaputra flood plains,thus preventing a recommendation for species level recognition without further study. 展开更多
关键词 Avian phylogenetics Indian subcontinent Indochinese region Multilocus analyses Ploceidae
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Fine mapping and transcriptome sequencing reveal candidate genes conferring all-stage resistance to stripe rust on chromosome arm 1AL in Chinese wheat landrace AS1676
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作者 Xiu Yang Yunfeng Jiang +18 位作者 Xianghai Yu Haipeng Zhang Yuqi Wang Fangnian Guan Li Long Hao Li Wei Li Qiantao Jiang Jirui Wang Yuming Wei Jian Ma Houyang Kang Pengfei Qi Qiang Xu Meng Deng Yazhou Zhang Youliang Zheng Yonghong Zhou Guoyue Chen 《The Crop Journal》 SCIE CSCD 2023年第5期1501-1511,共11页
Stripe rust, caused by Puccinia striiformis f. sp. tritici(Pst), threatens wheat production worldwide, and resistant varieties tend to become susceptible after a period of cultivation owing to the variation of pathoge... Stripe rust, caused by Puccinia striiformis f. sp. tritici(Pst), threatens wheat production worldwide, and resistant varieties tend to become susceptible after a period of cultivation owing to the variation of pathogen races. In this study, a new resistance gene against Pst race CYR34 was identified and predicted using the descendants of a cross between AS1676, a highly resistant Chinese landrace, and Avocet S, a susceptible cultivar. From a heterozygous plant from a F7recombinant inbred line(RIL) population lacking the Yr18 gene, a near-isogenic line(NIL) population was developed to map the resistance gene. An allstage resistance gene, YrAS1676, was identified on chromosome arm 1AL via bulked-segregant exomecapture sequencing. By analyzing a large NIL population consisting of 6537 plants, the gene was further mapped to the marker interval between KA1A_485.36 and KA1A_490.13, spanning 485.36–490.13 Mb on1AL. A total of 66 annotated genes have been reported in this region. To characterize and predict the candidate gene(s), an RNA-seq was performed using NIL-R and NIL-S seedlings 3 days after CYR34 inoculation. Compared to NIL-S plants, NIL-R plants showed stronger immune reaction and higher expression levels of genes encoding pathogenesis-associated proteins. These differences may help to explain why NIL-R plants were more resistant to Pst race CYR34 than NIL-S plants. By combining fine-mapping and transcriptome sequencing, a calcium-dependent protein kinase gene was finally predicted as the potential candidate gene of YrAS1676. This gene contained a single-nucleotide polymorphism. The candidate gene was more highly expressed in NIL-R than in NIL-S plants. In field experiments with Pst challenge,the YrAS1676 genotype showed mitigation of disease damage and yield loss without adverse effects on tested agronomic traits. These results suggest that YrAS1676 has potential use in wheat stripe rust resistance breeding. 展开更多
关键词 Stripe rust All-stage resistance(ASR) BSE-Seq Transcriptome analyses Candidate genes
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Sustainability of lime stabilized road subgrade in mountainous regions of Türkiye
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作者 Yavuz ABUT İlknur BOZBEY Ece KURT BAL 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2436-2452,共17页
In this paper the use of lime stabilized subgrade for low volume roads in two regions with high mountains and different frost penetration conditions in Türkiye was investigated in terms of design,performance,and ... In this paper the use of lime stabilized subgrade for low volume roads in two regions with high mountains and different frost penetration conditions in Türkiye was investigated in terms of design,performance,and cost.Pavements on unstabilized and stabilized subgrade were designed for two regions(Izmir and Van),covering all climate variations.The resilient modulus of the lime stabilized subgrade with different soil pulverization levels for non-freezing and freezing conditions were taken from a previous laboratory study.Frost effects were considered in pavement design using two different approaches,including limited subgrade frost penetration method and reduced subgrade strength method.Detailed application and evaluation were performed for all steps.Lime stabilized subgrades significantly reduced the thickness of base courses,and the benefit of lime stabilization was highly dependent on soil pulverization level.A detailed cost analysis on the unstabilized and stabilized cases found that the use of lime stabilization in the subgrade provided significant initial cost savings.Comparative analysis by using the AASHTO(1993)method and KENPAVE software,and quantity effect of soil pulverization level on the performance of low volume roads from a service life perspective,show that subgrade resilient modulus can be estimated.It is also possible to make correct performance estimation in the field.The results of the study show that lime stabilization is a good solution for low volume roads in the mountainous regions of Türkiye. 展开更多
关键词 Aggregate Surfaced Roads Lime Stabilization Soil Pulverization Levels Road Design Service Life Cost analyses
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Identification and comparison of the local physicochemical structures of transition metal-based layered double hydroxides for high performance electrochemical oxygen evolution reactions
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作者 Min Sung Kim Bipin Lamichhane +5 位作者 Ju-Hyeon Lee Jin-Gyu Bae Jeong Yeon Heo Hyeon Jeong Lee Shyam Kattel Ji Hoon Lee 《Journal of Energy Chemistry》 SCIE EI CSCD 2023年第12期89-97,I0004,共10页
Layered double hydroxides(LDHs) have attracted considerable attention as a cost effective alternative to the precious iridium-and ruthenium-based electrocatalysts for an oxygen evolution reaction(OER),a bottleneck of ... Layered double hydroxides(LDHs) have attracted considerable attention as a cost effective alternative to the precious iridium-and ruthenium-based electrocatalysts for an oxygen evolution reaction(OER),a bottleneck of water electrolysis for sustainable hydrogen production.Despite their excellent OER performance,the structural and electronic properties of LDHs,particularly during the OER process,remain to be poorly understood.In this study,a series of LDH catalysts is investigated through in situ X-ray absorption fine structure analyses and density functional theory(DFT) calculations.Our experimental results reveal that the LDH catalyst with equal amounts of Ni and Fe(NF-LDH) exhibits the highest OER activity and catalytic life span when compared with its counterparts having equal amounts of Ni and Co(NC-LDH)and Ni only(Ni-LDH).The NF-LDH shows a markedly enhanced OER kinetics compared to the NC-LDH and the Ni-LDH,as proven by the lower overpotentials of 180,240,and 310 mV,respectively,and the Tafel slopes of 35.1,43.4,and 62.7 mV dec^(-1),respectively.The DFT calculations demonstrate that the lowest overpotential of the NF-LDH is associated with the active sites located at the edge planes of NF-LDH in contrast to those located at the basal planes of Ni-LDH and NC-LDH.The current study pinpoints the active sites on various LDHs and presents strategies for optimizing the OER performance of the LDH catalysts. 展开更多
关键词 Layered double hydroxides Oxygen evolution reaction In situ X-ray analyses Density functional theory Catalytic active sites
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