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Characteristics and Driving Forces of Spatial Expansion of Oasis Cities and Towns in Hexi Corridor, Gansu Province, China

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Chinese Geographical Science 2015年第2期25卷 250-262页

作者： LIU Hailong SHI Peiji TONG Huali zhu Guofeng LIU Haimeng ZHANG xuebin WEI Wei WANG Xinmin College of Geography and Environmental Science Northwest Normal University

This paper presents an integrated study of urban spatial expansion in the Hexi Corridor, Gansu Province, China based on TM, ETM remote sensing data in 1987, 1990, 1995, 2000, 2006 and 2011. The study explores the characteristics of urban spatial expansion and dynamic mechanism by using expansion speed index, expansion intensity index, compact index, fractal dimension, and extended flexibility index. We built the index system of influencing factors of urban spatial expansion by using the grey incidence model. The results showed that urban spatial expansion rate in the Hexi Corridor has been on the upward trend since 1987. Expansion intensity showed an obvious upward trend, however, the upward trend varied in different urban areas. In addition, the urban structure was loose relatively, but the urban compactness was more obvious. The urban spatial form tended to be simple, and the urban land use tended to become more intensive. Urban spatial expansion experienced several stages: padding internally, external expansion and padding internally. The main driving factors of urban spatial expansion are not the urban water resources and the oasis scale, but one or several factors such as economy, traffic, population, resource and national policy.

关键词： spatial expansion driving forces oasis cities and towns Hexi Corridor China

Testis Development and Ultrastructural Features During Spermatogenesis in Cultured Small Yellow Croaker,Larimichthys polyactis

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Journal of Ocean University of China 2023年第5期22卷 1412-1426页

作者： ZHENG xuebin WANG Jingqian GAO Xinming DU Chen HOU Congcong XIE Qingping LIU Feng zhu Junquan LOU Bao Key Laboratory of Applied Marine Biotechnology by the Ministry of Education School of Marine SciencesNingbo UniversityNingbo 315211China Zhejiang Academy of Agricultural Sciences Hangzhou 310021China

The small yellow croaker Larimichthys polyactis is an economically important marine fish in Northeast ***,its natural resources are threatened by overfishing and environmental ***,research on the reproductive system of the fish is ***,we studied the testis development and ultrastructural features of spermatogenesis in cultured *** using anatomical,histological,and ultrastructural techniques.A pair of testes,consisting of a central sperm duct and radial seminiferous lobules,were *** reproduction cycle of testes can be divided into stages I–*** to May was confirmed as the breeding season for male ***,while April is the ideal period for artificial *** male *** can attain sexual maturity within 1 *** spermatogenesis of *** comprised spermatogonium,spermatocyte,spermatid,and mature *** morphology of spermatogenic cells changed obviously during spermiogenesis,including nuclear shaping,midpiece and flagellum *** mature sperms consist of an ellipsoidal head,a short midpiece,and a long *** anterior of the head with a kidney-shaped nucleus can be *** midpiece is located posterior to the head and includes four to six spherical *** flagellum has irregular lateral *** testis of *** is an unrestricted lobular type,with cystic spermatogenesis,type II spermiogenesis,and type II *** features are highly similar to those of other Sciaenid *** findings provide useful insights into the mechanism underlying testis development and spermatogenesis of ***,which can facilitate the artificial breeding of this species.

关键词： testis development spermatogenesis Larimichthys polyactis histology ultrastructure

Effects of capture and captivity on plasma corticosterone and metabolite levels in breeding Eurasian Tree Sparrows

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Avian Research 2019年第2期10卷 228-237页

作者： Mo Li Weiwei zhu Yang Wang Yanfeng Sun Juyong Li Xuelu Liu Yuefeng Wu xuebin Gao Dongming Li Key Laboratory of Animal Physiology Biochemistry and Molecular Biology of Hebei ProvinceCollege of Life SciencesHebei Normal UniversityShijiazhuang 050024China Ocean College of Hebei Agricultural University Qinhuangdao 066003China Shaanxi Institute of Zoology Xi’an 710032China

Background: Bringing free-living animals into captivity subjects them to the stress of both capture and captivity, leading to the alteration of normal physiological processes and behaviors through activation of the hypothalamic– pituitary–adrenal axis. In free-living birds, although elevated plasma corticosterone (CORT) is an important adaptation regulating physiological and behavioral responses during the process of capture and captivity stress, little information is currently available on the effects of such stress on plasma metabolite levels. Methods: We examined the effects of immediate capture and 24-h captivity on body mass, body condition, plasma CORT, and metabolite levels including glucose (Glu), triglyceride (TG), total cholesterol (TC), uric acid (UA), in breeding Eurasian Tree Sparrows (Passer montanus). Results: CORT and Glu levels were increased significantly by the stress of capture, whereas TC and UA levels decreased. Body mass, body condition declined notably after 24 h in captivity, but CORT, Glu, and UA levels increased. Furthermore, male sparrows had lower TG levels after both capture and captivity than those of females. The relationships between plasma CORT and metabolite levels varied between sexes. Conclusions: Our results revealed that the metabolic status of Eurasian Tree Sparrows could be dramatically altered by capture and captivity. Monitoring the dynamic effects of both capture and captivity on plasma CORT, metabolite levels in a free-living bird contributes to a better understanding of the stress-induced pathways involved in sexdependent energy mobilization.

关键词： Capture stress Captivity stress Corticosterone Plasma metabolites Free-living birds

Evidence for the role of KIF17 in fish spermatid reshaping:expression pattern of KIF17 in Larimichthys polyactis spermiogenesis

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Journal of Oceanology and Limnology 2021年第6期39卷 2322-2335页

作者： Jingqian WANG Xinming GAO xuebin ZHENG Chen DU Congcong HOU Qingping XIE Bao LOU Feng LIU Shan JIN Junquan zhu Key Laboratory of Applied Marine Biotechnology by the Ministry of Education School of Marine SciencesNingbo UniversityNingbo 315211China Zhejiang Academy of Agricultural Sciences Hangzhou 310021China

The homodimeric kinesin-2 protein KIF17 functions in intracellular transport and spermiogenesis in ***,its role in fish spermiogenesis has not been ***,we aimed to clone full-length kif17 cDNA and determine the molecular characteristics and expression patterns of KIF17 in Larimichthys polyactis *** full-length cDNA of *** kif17(Lp-kif17)was sequenced and found to contain a 332-bp 5′untranslated region,480-bp 3′untranslated region,and 2433-bp open reading frame encoding 810 amino *** analyses showed that *** KIF17(Lp-KIF17)shared high sequence similarity with homologs in other animals and possessed an N-terminal motor domain with microtubule-binding sites and adenosine triphosphate(ATP)hydrolysis sites,a stalk domain containing two coiled-coil regions,and a C-terminal tail *** Lp-kif17 mRNA was widely expressed in various tissues,with the highest level in the brain,followed by that in the *** in situ hybridization(FISH)analysis revealed that Lp-kif17 was continuously expressed in spermiogenesis,showing that it had potential functions in this *** immunofluorescence(IF)analysis,we found that Lp-KIF17 colocalized with tubulin and was transferred from the perinuclear cytoplasm to the side of spermatid where the tail forms during *** findings suggested that KIF17 is involved in *** *** particular,it may participate in nuclear shaping and tail formation by interacting with perinuclear microtubules during spermatid *** addition to providing evidence for the role of KIF17 in fish spermatid reshaping,this study provides important data for studies of reproductive biology in ***.

关键词： KIF17 spermiogenesis Larimichthys polyactis spermatid reshaping

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主斜井带式输送机软驱动技术浅析

煤矿机械 2025年第1期46卷 92-95页

作者：徐锐祥朱文焱张荣高刚刚陆学斌兰州信息科技学院智能装备学院兰州730300

随着煤矿行业对高效率和环保要求的不断提升,主斜井带式输送机的驱动技术也在不断发展。分析了3种主要的软驱动形式:变频减速驱动方式、液力偶合器驱动方式及永磁直驱方式。对这些驱动方式的工作原理、优缺点及其应用场景进行了综合评估... 详细信息

随着煤矿行业对高效率和环保要求的不断提升,主斜井带式输送机的驱动技术也在不断发展。分析了3种主要的软驱动形式:变频减速驱动方式、液力偶合器驱动方式及永磁直驱方式。对这些驱动方式的工作原理、优缺点及其应用场景进行了综合评估,这些技术不仅提升了运输效率,还保障了系统运行的稳定性和安全性,是煤矿高效开采的重要技术支撑。

关键词：带式输送机软驱动变频减速液力偶合器永磁直驱

Solid-gas Phase Preparation Method for Porous Molybdenum Trioxide

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Journal of Wuhan University of Technology(Materials Science) 2020年第3期35卷 495-500页

作者： REN Jie MU Shichun YANG Daohe LI Xuejing DONG Shengqi zhu Junwei LIN Xianghai DONG xuebin State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Wuhan Construction Engineering Safety Supervision Station Wuhan 430015China School of Civil Engineering Wuhan Univer-sityWuhan 430072China

A novel solid-gas reaction preparation technology was used to adjust the composition and microstructure of the composite crystal materials by changing the preparation parameters. Compared with the commonly used sol-gel method, acid base neutralization sedimentation method, hydrothermal method, and gas phase deposition method, the technology was relatively simplified and the elemental composition was controllable, without the use of openings and additives. A kind of multi-element composite porous metal oxide was obtained by pre-intercalation and decarburization. In order to increase the porosity of MoO3 material and promote the adsorption and diffusion of reactant molecules, the microstructure of MoO3 was studied. The preparation process of porous molybdenum trioxide by solid gas combination process was discussed, which provides an innovative idea for the design and preparation of new materials with a large specific surface area and other desirable properties.

关键词： molybdenum trioxide porous structure solid-gas phase method synthetic

Predicting Chemical Immunotoxicity through Data-Driven QSAR Modeling of Aryl Hydrocarbon Receptor Agonism and Related Toxicity Mechanisms

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Environment & Health 2024年第7期2卷 474-485页

作者： Nada J.Daood Daniel P.Russo Elena Chung xuebin Qin Hao zhu Predicting Chemical Immunotoxicity through Data-Driven QSAR Modeling of Aryl Hydrocarbon Receptor Agonism and Related Toxicity Mechanisms Department of Chemistry and Biochemistry Rowan UniversityGlassboroNew Jersey 08028United States Center for Biomedical Informatics and Genomics Tulane University School of MedicineNew OrleansLouisiana 70112United States Tulane National Primate Research Center Tulane University School of MedicineCovingtonLouisiana 70433United States

Computational modeling has emerged as a time-saving and cost-effective alternative to traditional animal testing for assessing chemicals for their potential ***,few computational modeling studies for immunotoxicity were reported,with few models available for predicting toxicants due to the lack of training data and the complex mechanisms of *** this study,we employed a data-driven quantitative structure–activity relationship(QSAR)modeling workflow to extensively enlarge the limited training data by revealing multiple targets involved in *** this end,a probe data set of 6,341 chemicals was obtained from a high-throughput screening(HTS)assay testing for the activation of the aryl hydrocarbon receptor(AhR)signaling pathway,a key event leading to *** this probe data set against PubChem yielded 3,183 assays with testing results for varying proportions of these 6,341 compounds.100 assays were selected to develop QSAR models based on their correlations to AhR *** individual QSAR models were built for each assay using combinations of four machine-learning algorithms and three molecular fingerprints.5-fold cross-validation of the resulting models showed good predictivity(average CCR=0.73).A total of 20 assays were further selected based on QSAR model performance,and their resulting QSAR models showed good predictivity of potential immunotoxicants from external *** study provides a computational modeling strategy that can utilize large public toxicity data sets for modeling immunotoxicity and other toxicity endpoints,which have limited training data and complicated toxicity mechanisms.

关键词： Immunotoxicity QSAR Machine learning Aryl hydrocarbon receptor Data mining

Prohibitin Protein Expression During Spermatogenesis in the Large Yellow Croaker, Larimichthys crocea

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Journal of Ocean University of China 2022年第5期21卷 1251-1264页

作者： LIN Chenwen GAO Xinming NI Jie ZHANG Shengshuo LIU Cheng LUO Shengyu DU Chen ZHENG xuebin HOU Congcong TANG Daojun ZHANG Chundan zhu Junquan Key Laboratory of Applied Marine Biotechnology by the Ministry of Education School of Marine SciencesNingbo UniversityNingbo 315211China

Mitochondria are important for animals’fertility,and their morphologies and functions during spermatogenesis are un-der ***,the molecular mechanism that regulates the mitochondrial dynamic during spermatogenesis is still *** this study,the cytological features of spermatogenesis were investigated in Larimichthys *** addition,the structure and function of prohibitin(PHB),which is associated with mitochondrial structure and dynamic,was also *** full-length cDNA and protein(Lc-PHB)from the *** phb gene(Lc-phb)contained 1625 base pairs and 271 amino acids,***-PHB had a conserved primary structure that resulted in a transmembrane,SPFH(the analogous region of proteins stomat-ins,prohibitins,flotillins and HflK/C),and coiled-coil *** was detected at high levels in the muscle,liver,and heart,and at intermediate levels in the testis,gill,and ***-phb mRNA expression was detected in spermatogenic cells by fluorescence in situ *** immunofluorescence assay revealed that PHB protein was localized in the mitochondria during ***,PHB expression was detected in the perinuclear cytoplasm of spermatogonia,spermatocytes,and spermatids in the early developmental stage,and mainly localized on one side of the nuclei in the cytoplasm of spermatids in a middle developmental stage,and finally on the sperm *** blotting showed that PHB was located in the extracted mitochondria protein fraction but not in the cytoplasm protein fraction of ***,these results indicated that PHB was expressed in the mitochondria dur-ing *** addition,the study explained the mitochondrial dynamic during fish spermatogenesis and proposed a possi-ble relationship among PHB,spermatogenesis,and male fertility.

关键词： spermatogenesis ultrastructure prohibitin expression pattern subcellular localization

Change in Surface Microstructure and Properties of PTFE after Solar Radiation and its Mechanism

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Journal of Wuhan University of Technology(Materials Science) 2019年第1期34卷 223-229页

作者： MA Guozheng WANG Haidou China Huayin Ordnance Test Center National Key Laboratory for Remanufacturing Academy of Armored Forces Engineering

A series of solar radiation tests for the polytetrafluoroethylene(PTFE) bulk and film samples were carried out using Q-SUN XE-3-HSC type Solar Radiation Simulator, with the test parameters as follows: radiation intensity is 1 120 W/m^2, temperature is 55 ℃ and humidity is 70% RH. Surface morphology, composition and microstructure of the PTFE samples before and after radiation tests were characterized contrastively. Effect of solar radiation on the tribology and wetting properties of PTFE were also studied by tribometer and contact angle tester, respectively. The results show that, for radiated PTFE, surface roughness, the relative content of C element, the friction coefficients and the contact angle with water increased in varying degrees. In conclusion, the obvious change in PTFE samples can be mainly attributed to break of(CFx)-C bonds after bombardment of high energy UV photons, which causes the loss of F-rich groups, oxidation, crosslinking and restructuring of active unsaturated groups.

关键词： solar radiation PTFE microstructure tribological properties wetting properties