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3D morphological characteristics of shrinkage porosities and their relationship with microstructures in Mg−12Al magnesium alloy
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作者 Chuang-ming LI Ang ZHANG +6 位作者 Yong-feng LI Heng-rui HU He LIU Yu-yang GAO Zhi-hua DONG Bin JIANG Fu-sheng PAN 《Transactions of Nonferrous Metals Society of China》 2026年第1期96-111,共16页
The dependence of shrinkage porosities on microstructure characteristics of Mg−12Al alloy was investigated.The distribution,morphology,size,and number density of shrinkage porosities were analyzed under different cool... The dependence of shrinkage porosities on microstructure characteristics of Mg−12Al alloy was investigated.The distribution,morphology,size,and number density of shrinkage porosities were analyzed under different cooling rates.The relationship between shrinkage porosities and microstructure characteristics was discussed in terms of temperature conditions,feeding channel characteristics,and feeding capacity.Further,the feeding behavior of the residual liquid phase in the solid skeleton was quantified by introducing permeability.Results show a strong correlation between the solid microstructure skeleton and shrinkage porosity characteristics.An increase in permeability corresponds to a declining number density of shrinkage porosities.This study aims to provide a more complete understanding how to reduce shrinkage porosities by controlling microstructure characteristics. 展开更多
关键词 Mg−12Al alloy shrinkage porosity SOLIDIFICATION microstructure characteristics morphological characteristics
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Morphological characteristics and corresponding functional properties of homeostatic human microglia
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作者 Pariya Khodabakhsh Olga Garaschuk 《Neural Regeneration Research》 2026年第3期1112-1113,共2页
Microglia,the resident immune cells of the central nervous system,exhibit a wide array of functional states,even in their so-called“homeostatic”condition,when they are not actively responding to overt pathological s... Microglia,the resident immune cells of the central nervous system,exhibit a wide array of functional states,even in their so-called“homeostatic”condition,when they are not actively responding to overt pathological stimuli.These functional states can be visualized using a combination of multi-omics techniques(e.g.,gene and protein expression,posttranslational modifications,mRNA profiling,and metabolomics),and,in the case of homeostatic microglia,are largely defined by the global(e.g.,genetic variations,organism’s age,sex,circadian rhythms,and gut microbiota)as well as local(specific area of the brain,immediate microglial surrounding,neuron-glia interactions and synaptic density/activity)signals(Paolicelli et al.,2022).While phenomics(i.e.,ultrastructural microglial morphology and motility)is also one of the key microglial state-defining parameters,it is known that cells with similar morphology can belong to different functional states. 展开更多
关键词 functional properties multi omics techniques protein expressionposttranslational modificationsmrna profilingand homeostatic human microglia morphological characteristics resident immune cells homeostatic microgliaare protein expression
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Effects of Morphological Awareness on Reading Comprehension in Beginner Chinese EFL Learners
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作者 Weiqi Huang Rendong Cai Xiaomei Yu 《Chinese Journal of Applied Linguistics》 2025年第4期566-584,639,共20页
This study investigates how English morphological awareness contributes to reading comprehension in beginner Chinese EFL learners.The research examines both derivational and compounding morphological awareness at mult... This study investigates how English morphological awareness contributes to reading comprehension in beginner Chinese EFL learners.The research examines both derivational and compounding morphological awareness at multiple levels(identification,discrimination,and manipulation)on English reading comprehension and explores whether their contributions are mediated by vocabulary knowledge.Data were collected from 71 Grade 9 students using various morphological awareness tasks,a vocabulary test,and a reading comprehension assessment.Mixed-effects regression and mediation analyses revealed that all components of morphological awareness,except derivational identification,significantly contributed to reading comprehension.Derivational manipulation was found to have both direct and indirect effects on reading comprehension,partially mediated by vocabulary knowledge.In contrast,compounding awareness influenced reading comprehension primarily through its effect on vocabulary.These findings provide a more nuanced understanding of how different facets of morphological awareness impact reading comprehension in EFL contexts,offering valuable insights for vocabulary and reading instruction. 展开更多
关键词 morphological awareness derivational morphology compounding morphology L2 reading comprehension
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Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ) double perovskites as oxygen electrodes for solid oxide cells:Effect of chemical composition and electrospun morphology 被引量:1
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作者 Jacek Winiarski Piotr Winiarz Konrad Świerczek 《International Journal of Minerals,Metallurgy and Materials》 2025年第11期2628-2638,共11页
Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)double perovskites are optimized for application in terms of chemical composi-tion and morphology for the use as oxygen electrodes in solid oxide cells.Structur... Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)double perovskites are optimized for application in terms of chemical composi-tion and morphology for the use as oxygen electrodes in solid oxide cells.Structural studies of other physicochemical properties are con-ducted on a series of materials obtained by the sol-gel method with different ratios of Gd and Sm cations.It is documented that changing the x value,and the resulting adjustment of the average ionic radius,have a significant impact on the crystal structure,stability,as well as on the total conductivity and thermomechanical properties of the materials,with the best results obtained for the Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)composition.Oxygen electrodes are prepared using the selected compound,allowing to obtain low polarization resistance values,such as 0.086Ω·cm^(2)at 800℃.Systematic studies of electrocatalytic activity are conducted using La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(_(0.2))O_(3−δ)as the electrolyte for all electrodes,and Ce_(0.8)Gd_(0.2)O_(2−δ)electrolyte for the best performing Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)electrodes.The electrochemical data are analyzed using the distribution of relaxation times method.Also,the influence of the preparation method of the electrode material is in-ve`stigated using the electrospinning technique.Finally,the performance of the Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)electrodes is tested in a Ni-YSZ(yttria-stabilized zirconia)anode-supported cell with a Ce_(0.8)Gd_(0.2)O_(2−δ)buffer layer,in the fuel cell and electrolyzer operating modes.With the electrospun electrode,a power density of 462 mW·cm^(−2)is obtained at 700℃,with a current density of ca.0.2 A·cm^(−2)at 1.3 V for the electrolysis at the same temperature,indicating better performance compared to the sol-gel-based electrode. 展开更多
关键词 multicomponent oxides double perovskites morphology modification ELECTROSPINNING oxygen electrodes solid oxide cells
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Enhanced risk assessment framework integrating distribution dynamics,genetically inferred populations,and morphological traits of Diploderma lizards 被引量:1
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作者 Qi Xiao Xiu-Dong Shi +5 位作者 Lin Shi Zhong-Yi Yao You-Hua Chen Wei-Zhao Yang Zi-Yan Liao Yin Qi 《Zoological Research》 2025年第1期15-26,共12页
Assessing the threat status of species in response to global change is critical for biodiversity monitoring and conservation efforts.However,current frameworks,even the IUCN Red List,often neglect critical factors suc... Assessing the threat status of species in response to global change is critical for biodiversity monitoring and conservation efforts.However,current frameworks,even the IUCN Red List,often neglect critical factors such as genetic diversity and the impacts of climate and land-use changes,hindering effective conservation planning.To address these limitations,we developed an enhanced extinction risk assessment framework using Diploderma lizards as a model.This framework incorporates long-term field surveys,environmental data,and land-use information to predict distributional changes for 10 recently described Diploderma species on the Qinghai-Xizang Plateau,which hold ecological significance but remain underassessed in conservation assessment.By integrating the distribution data and genetically inferred effective population sizes(Ne),we conducted scenario analyses and used a rank-sum approach to calculate Risk ranking scores(RRS)for each species.This approach revealed significant discrepancies with the IUCN Red List assessments.Notably,D.yangi and D.qilin were identified as facing the highest extinction risk.Furthermore,D.vela,D.batangense,D.flaviceps,D.dymondi,D.yulongense,and D.laeviventre,currently classified as“Least Concern”,were found to warrant reclassification as“Vulnerable”due to considerable threat from projected range contractions.Exploring the relationship between morphology and RRS revealed that traits such as snout-vent length and relative tail length could serve as potential predictors of extinction risk,offering preliminary metrics for assessing species vulnerability when comprehensive data are unavailable.This study enhances the precision of extinction risk assessment frameworks and demonstrates their capacity to refine and update risk assessments,especially for lesser-known taxa. 展开更多
关键词 LIZARD Extinction Risk Assessment IUCN Red List Conservation Status Effective Population Size morphological Traits
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High-Precision and Ultraspeed Monitoring of Melt-Pool Morphology in Laser-Directed Energy Deposition Using Deep Learning 被引量:1
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作者 Jiayu Yang Guan Liu +4 位作者 Wei Zhu Yingjie Zhang Wenbin Zhou Defu Liu Yongcheng Lin 《Additive Manufacturing Frontiers》 2025年第2期81-89,共9页
Laser-directed energy deposition(L-DED)is an advanced additive manufacturing technology primarily adopted in metal three-dimensional printing systems.The L-DED process is characterized by various defects,thus necessit... Laser-directed energy deposition(L-DED)is an advanced additive manufacturing technology primarily adopted in metal three-dimensional printing systems.The L-DED process is characterized by various defects,thus necessitating the extensive use of in-situ monitoring to enable real-time adjustments of process parameters by detecting molten-pool features.To address the challenge of accurately extracting the molten-pool morphology from an undetached spatter,an innovative monitoring method based on the U-Net(U-shaped network)is proposed herein.A lightweight architecture accelerates the processing speed,whereas an enhanced loss function incorporating weight maps augments the segmentation precision.The model performance is evaluated by comparing its segmentation accuracy and processing speed with those of the conventional U-Net,using the mean intersection over union(MIoU)as the segmentation metric.The improved model demonstrates superior segmentation accuracy at the interface between the molten pool and spatter,with a peak MIoU of 0.9798 achieved on the test set.Furthermore,this model processes each image in an extremely short time of 17.9 ms.Using this segmentation algorithm,the error in extracting the molten-pool width from single-track experiments is within 0.1 mm.The proposed method for monitoring the molten-pool morphology is suitable for deployment in online monitoring systems,thus providing a foundation for subsequent process-parameter regulation. 展开更多
关键词 Laser-directed energy deposition Molten-pool morphology Semantic segmentation Mean intersection over union(MIoU)
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Morphology engineering of ZnO micro/nanostructures under mild conditions for optoelectronic application
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作者 Liang Chu Haoyu Shen +3 位作者 Hudie Wei Hongyu Chen Guoqiang Ma Wensheng Yan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期498-503,共6页
Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV.Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,si... Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV.Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,simplicity,and easy implementation.Moreover,ZnO morphology engineering has become desirable through the alteration of minor conditions in the reaction process,particularly at room temperature.In this work,ZnO micro/nanostructures were synthesized in a solution by varying the amounts of the ammonia added at low temperatures(including room temperature).The formation of Zn^(2+)complexes by ammonia in the precursor regulated the reaction rate of the morphology engineering of ZnO,which resulted in various structures,such as nanoparticles,nanosheets,microflowers,and single crystals.Finally,the obtained ZnO was used in the optoelectronic application of ultraviolet detectors. 展开更多
关键词 morphology engineering low temperature ZnO nanosheets microflowers ultraviolet detector
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Novel homozygous SPAG17 variants cause human male infertility through multiple morphological abnormalities of spermatozoal flagella related to axonemal microtubule doublets 被引量:1
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作者 Tao Liu Fazal Rahim +15 位作者 Meng-Lei Yang Meftah Uddin Jing-Wei Ye Imtiaz Ali Yousaf Raza Abu Mansoor Muhammad Shoaib Mujahid Hussain Ihsan Khan Basit Shah Asad Khan Ahmad Nisar Hui Ma Bo Xu Wasim Shah Qing-Hua Shi 《Asian Journal of Andrology》 2025年第2期245-253,共9页
Male infertility can result from impaired sperm motility caused by multiple morphological abnormalities of the flagella(MMAF).Distinct projections encircling the central microtubules of the spermatozoal axoneme play p... Male infertility can result from impaired sperm motility caused by multiple morphological abnormalities of the flagella(MMAF).Distinct projections encircling the central microtubules of the spermatozoal axoneme play pivotal roles in flagellar bending and spermatozoal movement.Mammalian sperm-associated antigen 17(SPAG17)encodes a conserved axonemal protein of cilia and flagella,forming part of the C1a projection of the central apparatus,with functions related to ciliary/flagellar motility,skeletal growth,and male fertility.This study investigated two novel homozygous SPAG17 mutations(M1:NM_206996.2,c.829+1G>T,p.Asp212_Glu276del;and M2:c.2120del,p.Leu707*)identified in four infertile patients from two consanguineous Pakistani families.These patients displayed the MMAF phenotype confirmed by Papanicolaou staining and scanning electron microscopy assays of spermatozoa.Quantitative real-time polymerase chain reaction(PCR)of patients’spermatozoa also revealed a significant decrease in SPAG17 mRNA expression,and immunofluorescence staining showed the absence of SPAG17 protein signals along the flagella.However,no apparent ciliary-related symptoms or skeletal malformations were observed in the chest X-rays of any of the patients.Transmission electron microscopy of axoneme cross-sections from the patients showed incomplete C1a projection and a higher frequency of missing microtubule doublets 1 and 9 compared with those from fertile controls.Immunofluorescence staining and Western blot analyses of spermatogenesis-associated protein 17(SPATA17),a component of the C1a projection,and sperm-associated antigen 6(SPAG6),a marker of the spring layer,revealed disrupted expression of both proteins in the patients’spermatozoa.Altogether,these findings demonstrated that SPAG17 maintains the integrity of spermatozoal flagellar axoneme,expanding the phenotypic spectrum of SPAG17 mutations in humans. 展开更多
关键词 C1a projection central apparatus male infertility multiple morphological abnormalities of the flagella SPAG17
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Unveiling the growth and morphological transition mechanisms of Al_(2)Cu intermetallic compounds quantified by synchrotron X-ray tomography 被引量:1
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作者 Zongye Ding Liao Yu +3 位作者 Naifang Zhang Wenquan Lu Jianguo Li Qiaodan Hu 《Journal of Materials Science & Technology》 2025年第6期43-54,共12页
Controlling the morphology of Al_(2) Cu intermetallic compounds(IMCs)has been of importance to enhance the properties of Al-based alloys.However,the quantification of Al_(2) Cu IMCs with diversified morphologies is st... Controlling the morphology of Al_(2) Cu intermetallic compounds(IMCs)has been of importance to enhance the properties of Al-based alloys.However,the quantification of Al_(2) Cu IMCs with diversified morphologies is still lacking,and the morphological evolution of Al_(2) Cu dendrites remains poorly understood.Using synchrotron X-ray tomography,we have directly quantified the morphological evolution of proeutectic Al_(2) Cu IMCs in directionally solidified Al-Cu alloys.The three-dimensional(3D)morphologies of Al_(2) Cu IMCs under different growth rates were quantified using volume,specific surface area,interconnectivity,tortuosity,and Gaussian curvature.The faceted morphology under slow growth rate was divided into three different types,including single hollow prism,irregular prism lacking partial faces,and coalesced prism consisting of two adjacent crystals.The morphological transition from faceted prism to non-faceted algae-like,irregular tree-like,and typically dendritic shapes with increasing growth rates was determined,reflecting the growth modes varied from lateral mode to intermediary and continuous modes.The non-faceted Al_(2) Cu dendrite had one primary stem,three groups of secondary arms,and a faceted tip.The angles between secondary arms were 120°,and the tip consisted of(011)and(011^(-))planes.This work provides a deep understanding of the formation and growth of complex IMCs in metallic alloys. 展开更多
关键词 Proeutectic Al_(2)Cu intermetallic Synchrotron tomography Directional solidification 3-D morphology
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The interaction between KIF21A and KANK1 regulates dendritic morphology and synapse plasticity in neurons
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作者 Shi-Yan Sun Lingyun Nie +5 位作者 Jing Zhang Xue Fang Hongmei Luo Chuanhai Fu Zhiyi Wei Ai-Hui Tang 《Neural Regeneration Research》 SCIE CAS 2025年第1期209-223,共15页
Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory.Kinesin-4 KIF21A helps organize the microtubule-actin network at th... Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory.Kinesin-4 KIF21A helps organize the microtubule-actin network at the cell cortex by interacting with KANK1;however,whether KIF21A modulates dendritic structure and function in neurons remains unknown.In this study,we found that KIF21A was distributed in a subset of dendritic spines,and that these KIF21A-positive spines were larger and more structurally plastic than KIF21A-negative spines.Furthermore,the interaction between KIF21A and KANK1 was found to be critical for dendritic spine morphogenesis and synaptic plasticity.Knockdown of either KIF21A or KANK1 inhibited dendritic spine morphogenesis and dendritic branching,and these deficits were fully rescued by coexpressing full-length KIF21A or KANK1,but not by proteins with mutations disrupting direct binding between KIF21A and KANK1 or binding between KANK1 and talin1.Knocking down KIF21A in the hippocampus of rats inhibited the amplitudes of long-term potentiation induced by high-frequency stimulation and negatively impacted the animals’cognitive abilities.Taken together,our findings demonstrate the function of KIF21A in modulating spine morphology and provide insight into its role in synaptic function. 展开更多
关键词 ACTIN CYTOSKELETON dendrite KANK1 KIF21A MICROTUBULE spine morphology SPINE synaptic plasticity talin1
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The application of mordenite with different crystal morphologies in isoamylene oligomerization
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作者 WANG Zijian LI Shuting +2 位作者 ZHENG Jiashuo KE Ming SONG Zhaozheng 《燃料化学学报(中英文)》 北大核心 2025年第11期1654-1662,共9页
The oligomerization of light olefins is considered a green production technology.Currently,the application of mordenite in isoamylene oligomerization faces two main challenges:low dimerization selectivity and poor sta... The oligomerization of light olefins is considered a green production technology.Currently,the application of mordenite in isoamylene oligomerization faces two main challenges:low dimerization selectivity and poor stability.In this work,a series of different SiO_(2)/Al_(2)O_(3) ratio mordenite are synthesized by utilizing hexamethyleneimine(HMI)as the organic structure directing agent,and it turns out that the rod-like zeolite with the ratio of SiO_(2)/Al_(2)O_(3)=14 exhibits the higher dimerization selectivity.The incorporation of TPOAC optimizes the pore structure and acid site distribution of the rod-like zeolite,which enables the samples to not only exhibit a conversion rate of isoamylene over 88.30% within 12 h,while maintaining good dimerization selectivity.These findings provide a promising approach for improving the efficiency and sustainability of olefin oligomerization processes. 展开更多
关键词 MORDENITE HEXAMETHYLENEIMINE crystal morphology isoamylene oligomerization
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Morphological and molecular characterization of Thelohanellus xiushanensis n.sp.infecting the gill filament of Carassius auratus
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作者 ZHANG Jinye WANG Miaomiao +3 位作者 WANG Yueru LIU Hongyan ZHANG Yiwen ZHAO Yuanjun 《水产学报》 北大核心 2025年第12期176-187,共12页
The exploration and understanding of myxosporean,one of the crucial stressors causing fish disease,have always been highly regarded.The present study aims to fully understand a novel myxobolid species,Thelohanellus xi... The exploration and understanding of myxosporean,one of the crucial stressors causing fish disease,have always been highly regarded.The present study aims to fully understand a novel myxobolid species,Thelohanellus xiushanensis n.sp.infecting the gill filaments of Carassius auratus from Chongqing,China,as well as the associated pathological impacts.A multifaceted analysis at various levels and perspectives was carried out by the approach integrating morphology,molecular systematics,histopathology,combined host and habitat,as well as SSU rDNA data.The results indicated that its mature myxospores displayed a tapering anterior and a blunt-rounded posterior,with a dropshape in front view and melon-seed shape in sutural view in morphology.The outer surface was covered with a transparent membrane sheath in valve view.The dimensions of myxospores were average(19.2±1.1)(17.1-21.0)×(10.0±0.7)(8.7-12.1)×(9.7±0.5)(9.1-10.8)μm.An elliptical polar capsule,containing four to five turns of single polar filament,measures(8.0±0.6)(6.9-9.1)×(6.6±0.3)(6.1-7.1)μm.Its SSU rDNA sequence demonstrated the closest similarity(99.95%)with an actinosporean Neoactinomyxum sp.NEO-7.Histopathological results indicated that numerous myxoplasmodia of T.xiushanensis n.sp.were located in the tips of the gill filaments,resulting in deformation and rupture of partial gill filaments.Furthermore,severely infected gill lamellae exhibited hyperplasia and fusion,accompanied by infiltration of numerous eosinophils.In addition,regenerated gill filaments were observed at the bases of partially ruptured gill filaments,indicating that the host’s gill tissue has the innate capacity to shed diseased tissues and regenerate new ones.This study has proved the present species and Neoactinomyxum sp.NEO-7 belong to the same myxosporean species but corresponding to different developmental stage,designated as a new species.This novel species is a potential pathogen for the host,which should not be ignored.This study not only enriches myxobolid biodiversity and demonstrates a potentially pathogenic agent,but also provides a valid diagnosis for the gill myxoboliosis caused by the present pathogen in aquaculture. 展开更多
关键词 Carassius auratus Thelohanellus xiushanensis n.sp. morphology phylogeny SSU rDNA
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Tuning support morphology to control alloy over PtCo/γ-Al_(2)O_(3) for the preferential oxidation of CO
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作者 SONG Lichuan ZHONG Liding +3 位作者 SHEN Jia LOU Yake GUO Yun WANG Li 《燃料化学学报(中英文)》 北大核心 2025年第1期96-105,共10页
The preferential oxidation of CO(CO-PROX)reaction is a cost-effective method for eliminating trace amounts of CO from the fuel H2.Pt-based catalysts have been extensively studied for COPROX,with their activity influen... The preferential oxidation of CO(CO-PROX)reaction is a cost-effective method for eliminating trace amounts of CO from the fuel H2.Pt-based catalysts have been extensively studied for COPROX,with their activity influenced by the morphology of the support.Hydrothermal synthesis was employed to produce different morphologies ofγ-Al_(2)O_(3):flower-likeγ-Al_(2)O_(3)(f)exposing(110)crystal faces,sheet-likeγ-Al_(2)O_(3)(s)revealing(100)crystal faces,and rod-likeγ-Al_(2)O_(3)(r)displaying(111)crystal faces,followed by loading PtCo nanoparticles.The exposed crystal faces of the support impact the alloying degree of the PtCo nanoparticles,and an increase in the alloying degree correlates with enhanced catalyst reactivity.Pt_(3)Co intermetallic compounds were identified onγ-Al_(2)O_(3)(f)exposing(110)crystal faces,and PtCo/γ-Al_(2)O_(3)(f)showed high catalytic activity in the CO-PROX reaction,achieving 100%CO conversion across a broad temperature range of 50−225°C.In contrast,only partial alloying of PtCo was observed onγ-Al_(2)O_(3)(s).Furthermore,no alloying between Pt and Co occurred in PtCo/γ-Al_(2)O_(3)(r),resulting in a reaction rate at 50°C that was merely 11%of that of PtCo/γ-Al_(2)O_(3)(f).The formation of Pt3Co intermetallic compounds led to a more oxidized state of Pt,which significantly diminished the adsorption of CO on Pt and augmented the active oxygen species,thereby facilitating the selective oxidation of CO. 展开更多
关键词 PtCo catalysts γ-Al_(2)O_(3) support morphology CO-PROX
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Morphology of the Left Atrial Appendage in the Senegalese: About 36 Anatomic Parts
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作者 Ndeye Bigué Mar Magaye Gaye +10 位作者 Sokhna Astou Gawane Thiam Issa Dior Seck Racky Wade Mamadou Ndiaye Daouda Tireira Aïnina Ndiaye Philippe Manyacka Ma Nyemb Jean Marc Ndiaga Ndoye Mamadou Diop Ablaye Ndiaye Assane Ndiaye 《Forensic Medicine and Anatomy Research》 2025年第1期1-7,共7页
Introduction: the left atrial appendage, a dormant embryonic vestige, would play a major role in cardiac hemodynamic changes, volume homeostasis and thrombi formation. It, therefore constitutes a therapeutic target. I... Introduction: the left atrial appendage, a dormant embryonic vestige, would play a major role in cardiac hemodynamic changes, volume homeostasis and thrombi formation. It, therefore constitutes a therapeutic target. Its morphology is extremely variable. Objective: it consisted on determining the morphological variations of the left auricle as well as their interest in the prevention of thrombi in the Senegalese. Material and Method: This study was conducted by dissecting 36 fresh hearts from Senegalese anatomical subjects with a sampling of the left atrial appendage, including specimens with normal morphological appearance. Their morphology was studied using the fresh and frozen plaster molding method. The data obtained were analyzed statistically. Results: the average age of the subjects was 33 years, with a sex ratio of 1.06, the cauliflower shape was dominant with 57% of cases and the cactus shape (4%) was less frequent. The cauliflower shape presented a clear angulation compared to the others without statistically significant differences according to age. Conclusion: This work showed a great morphological variability of the left atrial appendage. It can provide an update on the specificity of Senegalese. Taking these variations into account is important in the safe management of hemodynamic conditions and the improvement of the management of recurrent strokes. 展开更多
关键词 Atrial Appendage morphologY STROKE
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Morphological Characteristics of Local Chicken Populations (Gallus gallus domesticus) in Farmed Basins of the Far North Region, Cameroon
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作者 Christophe Wang-baa Temoa Jean Massawa +2 位作者 Francis Dongmo Djiotsa Yakouba Manjely Felix Meutchieye 《Open Journal of Animal Sciences》 2025年第1期51-68,共18页
In order to contribute to a better understanding of the biodiversity of local chicken populations, this study focused on the description of the essential qualitative parameters in the phenotypic characterization of lo... In order to contribute to a better understanding of the biodiversity of local chicken populations, this study focused on the description of the essential qualitative parameters in the phenotypic characterization of local species. Conducted in 6 localities in the Far North Region of Cameroon (Doukoula, Yagoua, Guidiguis, Dziguilao, Maroua 3rd and Méri), a population of 240 local chickens, including 172 hens and 68 cocks were characterized in family farms. The choice of localities was made on the basis of their strong potential local chicken flocks in the region. To this end, each animal was the subject of a qualitative description based on the identification of the sex of the animal, the description of the colorations of the plumage and extremities, and the description of the types of format, plumage and crests. All observations were made with the naked eye and in daylight and then photographed. The main results show that the plumage colors are multiple and dominated by the White-Pied-Black (21.7%) and the Mille-fleur (20.8%);the wattles are dominated by the red (60%) and the pink (35.4%);the tarsi are dominated by the white (43.8%) and the black (32.08%);the white skin (92.5%) dominates over the pink skin (7.5%);the “Smooth-uniform” feather is dominant (97.08%), followed by the smooth-crested type (2.08%) and the fries type (0.82%);the medium size of the chickens is dominant (86.66%), followed by the dwarf size (9.58%) and the large size (3.75%). The results of this study demonstrate that there is a strong phenotypic diversity within the local chicken population. This diversity can serve as a basis for the development of selection, conservation and genetic potential improvement programs based on rational exploitation of the local chicken. 展开更多
关键词 morphological Characteristics Local Chicken Far North Cameroon
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Volcanic Geomorphology and Morphometry Classification of Cinder Cone in Harrat Lunayyir Saudi Arabia by Using GIS and Remote Sensing
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作者 Azizah Aziz al Shehri 《Journal of Environmental & Earth Sciences》 2025年第5期304-318,共15页
Harrat Lunayyir,a volcanic field in western Saudi Arabia,exhibits diverse geomorphological and topographical features shaped by volcanic,tectonic,and climatic processes.This study integrates field observations,remote ... Harrat Lunayyir,a volcanic field in western Saudi Arabia,exhibits diverse geomorphological and topographical features shaped by volcanic,tectonic,and climatic processes.This study integrates field observations,remote sensing,and GIS analysis to investigate the spatial distribution and relationships between volcanic landforms,lava flows,and topographical variation result obtained is a morphological classification of the cinder cones of Harrat Lunayyir,which can be sub-divided into four types:tephra rings,horseshoe-shaped volcanoes,multiple volcanoes and volcanoes without craters.All of these are monogenetic volcanoes,unlike central volcanoes(stratovolcanoes)which live for tens or hundreds of thousands of years and erupt numerous times.In Harrat Lunayyir,there is a clear dominance of arched horseshoe-shaped volcanoes(58)over ring-shaped cinder cones(10),A1_symmetric cones(circular,uniform cinder cones with a single crater)(32),A2_asymmetric cones(elongated,irregular cones and may feature one or more craters)(8),volcanoes without craters(55)and multiple volcanoes(20).The classification presented in this paper makes it possible to include all morphological types of volcanoes found in the region.This fact also renders the present classification a useful tool to apply in other,both insular and continental volcanic areas to eventually analyze and systematize the study of eruptive edifices with similar traits.Hence,this research will explore the standard physical volcanology literature so as to follow accepted definitions. 展开更多
关键词 GIS morphology DEM Topography LITHOLOGY Cinder Cones
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Novel insight into the site-specificity of Hegu (LI4): morphological, biomechanical, and histological analyses
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作者 Kanae Umemoto SHAN Xiyao +3 位作者 Takuro Ishikawa Tadashi Watsuji Yasuharu Watanabe Munekazu Naito 《Journal of Traditional Chinese Medicine》 2025年第4期867-872,共6页
OBJECTIVE:To investigate the site specificity and differences of the Hegu(LI4)located on the midpoint of the second metacarpal and the point where the bases of the first and second metacarpal bones on the dorsum was h... OBJECTIVE:To investigate the site specificity and differences of the Hegu(LI4)located on the midpoint of the second metacarpal and the point where the bases of the first and second metacarpal bones on the dorsum was historically used as Hegu(LI4)in Japan,through morphological,biomechanical,and histological analyses.METHODS:We defined distally located Hegu(LI4)as Hegu(LI4)-D and proximally located Hegu(LI4)as Hegu(LI4)-P.The distance from the skin surface to the blood vessels as well as the biomechanical properties of the two Hegu(LI4)samples were measured using an ultrasound device and Myoton PRO(Myoton AS,Tallinn,Estonia),respectively,in 20 healthy adult volunteers.Sympathetic fibers under the two Hegu(LI4)samples were histologically observed using tyrosine hydroxylase(TH)immunostaining in 10 cadavers.RESULTS:Hegu(LI4)-D was classified into type 1 with blood vessels<4 mm away from the skin surface,and type 2 with blood vessels>10 mm away from the skin surface.In Hegu(LI4)-P,blood vessels were approximately 10 mm away from the surface.Further,Hegu(LI4)-P had significantly higher tone,stiffness,and elasticity than Hegu(LI4)-D(P<0.0001).TH-positive fibers were present near the artery in Hegu(LI4)-P.CONCLUSION:Hegu(LI4)-D and Hegu(LI4)-P differed in terms of hardness and the distance between the skin surface and blood vessels.Furthermore,sympathetic nerve fibers were present near the artery in Hegu(LI4)-P.Taken together,these results suggest that there is site specificity of morphological,biomechanical,and histological differences between the Hegu(LI4)-D and Hegu(LI4)-P. 展开更多
关键词 acupuncture ultrasonic therapy metacarpal bones HISTOLOGY morphology biomechanism
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Correction to:Functional reproductive morphology of the snapping shrimp genus Synalpheus Spence Bate,1888(Decapoda,Alpheidae)
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《Current Zoology》 2025年第3期408-408,共1页
This is a correction to:Isabela R R Moraes,Mariana Antunes,Laura S Lopez-Greco,Fernando Jose Zara,Antonio Leao Castilho,Functional reproductive morphology of the snapping shrimp genus Synalpheus Spence Bate,1888(Decap... This is a correction to:Isabela R R Moraes,Mariana Antunes,Laura S Lopez-Greco,Fernando Jose Zara,Antonio Leao Castilho,Functional reproductive morphology of the snapping shrimp genus Synalpheus Spence Bate,1888(Decapoda,Alpheidae),Current Zoology,2024,71,338-352;https:/doi.org/10.1093/cz/zoae053. 展开更多
关键词 Synalpheus reproductive morphology ALPHEIDAE snapping shrimp DECAPODA
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Morphology,transcriptome,and proteome analysis of gill tissue in Acanthopagrus latus infected with Cryptocaryon irritans
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作者 Luxin Bai Man Jiang +3 位作者 Dongling Zhang Jing Zhang Liangmin Huang Xiande Liu 《Acta Oceanologica Sinica》 2025年第9期145-157,共13页
Cryptocaryon irritans is the parasite responsible for“white spot disease”in the yellowfin seabream Acanthopagrus latus,which has caused significant losses to the aquaculture industry.This experiment investigated the... Cryptocaryon irritans is the parasite responsible for“white spot disease”in the yellowfin seabream Acanthopagrus latus,which has caused significant losses to the aquaculture industry.This experiment investigated the changes in the morphology,transcriptome,and proteome of gill tissue in yellowfin seabream infected with C.irritans,aiming to provide foundational data for further understanding the pathogenic mechanisms and control measures against this parasite.The main findings were as follows,after C.irritans infection,the structure of gill tissue in yellowfin seabream was damaged,with microvessels ruptured,some cells proliferating,and large amounts of mucus infiltrating.Transcriptome analysis revealed a total of 4299 differentially expressed genes,with 2367 up-regulated and 1932down-regulated.Further bioinformatics analysis of all differentially expressed genes identified nine immune-related genes,cox-2,mcama,tbx21,dcn,tnfb,cd74a,illb,ppib,and cd4-1 in A.latus.The reliability of the transcriptome data was validated by real time q PCR,which showed the same trend as the RNA-seq results.Proteome analysis found365 differential proteins,with 180 proteins up-regulated and 185 proteins down-regulated.Bioinformatics analysis identified three immune-related proteins,Myll,Gapdh,and Actn3b.These findings indicated that C.irritans disrupted the structure of gill tissue,impeded gas exchange and led to asphyxiation and death in affected fish.Transcriptome and proteome analyses showed that the expression of immune-related genes and proteins in yellowfin seabream,involved not only inflammatory responses and the activation and migration of immune cells but also potentially participated in tissue repair and defense regulation.These findings highlighted the complex immune regulatory network in response to C.irritans infection,offering references for prevention and control of white spot disease in yellowfin seabream. 展开更多
关键词 Cryptocaryon irritans yellowfin seabream morphologY TRANSCRIPTOME PROTEOME immune response
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Contributions of temperature and development state to the morphological variation of Ulva prolifera highlight the source management for green tides
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作者 Kai-Ming Sun Changlin Li +2 位作者 Xiaoxiang Miao Shiliang Fan Zongling Wang 《Journal of Environmental Sciences》 2025年第12期351-360,共10页
Since 2007,the world's largest transregional green tides caused by Ulva prolifera have periodically occurred in China.The morphology of U.prolifera drastically changes during the drifting period,but the reason for... Since 2007,the world's largest transregional green tides caused by Ulva prolifera have periodically occurred in China.The morphology of U.prolifera drastically changes during the drifting period,but the reason for this phenomenon has still been under debate.Our results showed that temperature partly explained the changes in the morphology of U.prolifera,with a determining factor of 0.498.The ratio of highly branched thalli decreased as the temperature increased from around 25 to 30℃.Because morphological changes and physiological acclimation synergistically occurred in floating macroalgae,we hypothesized that if the morphology of U.prolifera is also determined by its development state,and the U.prolifea thalli with different development states should have distinct morphological and physiological traits even under the same environmental conditions.To test the hypothesis,we investigated the photosynthesis of U.prolifera and found a higher photosynthetic capacity but lower photoprotective capacity in algae that grew in the branched development state compared to those in the unbranched development state.Combined with other field observations and lab experiments,we suggest that both temperature and development state contribute to the morphological changes of U.prolifera.Given the varying trends of temperature during U.prolifera blooms in past eleven years and the initial occurrence of U.prolifera thalli in the branched development state in the source of algal bloom,we emphasize the need for source management of green tides. 展开更多
关键词 Ulva prolifera morphology PHOTOSYNTHESIS DESICCATION Algal control
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