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Dynamics of iron and aluminum storages in a subtropical forest headwater stream

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Journal of Mountain Science 2024年第7期21卷 2193-2205页

作者： YI Qiumeng MA Diting peng yan ZHAO Zemin YUAN Chaoxiang YUAN Ji NI Xiangyin WU Fuzhong YUE Kai AN Nannan Key Laboratory of Humid Subtropical Eco-geographical Processes of Ministry of Education School of Geographical SciencesFujian Normal UniversityFuzhou 350117China Fujian Sanming Forest Ecosystem National Observation and Research Station Sanming 365002China

The forest headwater streams are important hubs for connecting terrestrial and aquatic ecosystems,with plant litter and sediments as the major carriers for material migrations;however,until now we knew little about the dynamics of trace elements such as iron(Fe)and aluminum(Al)in forest headwater streams.Here,we quantitatively identified the spatiotemporal dynamics of Fe and Al storages in plant litter and sediments and their influencing factors in a subtropical forest headwater stream,and assessed the potential pollution risk.The results showed that:(1)the mean concentrations of Fe and Al in plant litter(sediments)were 5.48 and 8.46(7.39 and 47.47)g·kg^(-1),and the mean storages of Fe and Al in plant litter(sediments)were 0.26 and 0.43(749.04 and 5030.90)g·m^(-2),respectively;(2)the storages of Fe and Al in plant litter and sediments significantly fluctuated from January to December,and showed a decreasing pattern from the source to mouth;and(3)storages of Fe and Al had no significant correlation with riparian forest type and the present of tributary and the Fe and Al storages in plant litter were mainly affected by water temperature and water alkalinity,and their storages in sediments were mainly affected by water temperature and frequency of rainfall;and(4)there were no anthropogenic pollution in Fe and Al in the forest headwater stream.Our study revealed the primary factors of concentrations and storages of Fe and Al in plant litter and sediments in a forest headwater stream,which will improve our understanding of the role of headwater streams in forest nutrient storage and cycling along with hydrological processes.

关键词： Plant litter Sediments Storage Forest headwater stream Stream characteristics Trace element

Application of prostate resectoscope in the treatment of massive rectal bleeding after transrectal prostate puncture

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World Journal of Clinical Cases 2024年第18期12卷 3438-3443页

作者： Hong-Mei Li Fa-Ying yang Song Tu peng yan Jun Qian Jia-Xi Yao Department of Urology Hexi University Affiliated Zhangye People’s HospitalHexi UniversityZhangye 734000Gansu ProvinceChina Department of General Surgery II Hexi UniversityZhangye 734000Gansu ProvinceChina

BACKGROUND Ultrasound-guided prostate biopsy is a reliable diagnostic procedure for prostate cancer diagnosis with minimal procedure-related trauma.However,complications,such as massive rectal bleeding may occur after the puncture.We hypothesized that using a transrectal resectoscope could help treat massive rectal bleeding after transrectal prostate punctures.AIM To identify a simple and effective treatment for massive rectal bleeding after transrectal prostate punctures.METHODS Patients requiring treatment for massive rectal bleeding after transrectal prostate punctures were included.A SIMAI resectoscope was inserted through the anus.Direct electrocoagulation was performed for superficial bleeding points.Part of the rectal mucosa or surface muscle layer was removed to expose deep bleeding points,followed by electrocoagulation.An electric cutting ring was used to compress and stop the bleeding for jet-like points before electrocoagulation.The fluid color in the drainage tube was monitored postoperatively for continuous bleeding.RESULTS Eight patients were included from 2012 to 2022.None of the patients with massive rectal bleeding after the transrectal prostate punctures improved with conventional conservative and blood transfusion treatments.Two patients had an inferior artery embolism,and digital subtraction angiography was ineffective.All patients received emergency transanal prostate resection,which immediately stopped the bleeding.Four days after the procedure,the patients had recovered and were discharged.CONCLUSION Using a transanal prostate resection instrument is a simple,safe,and effective method for treating massive rectal bleeding after transrectal prostate punctures.

关键词： Electrocoagulation Hemostasis Transanal prostate resection instrumentation Prostate puncture

Thermal and mechanical behavior of casting copper alloy wheel during wheel and belt continuous casting process

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China Foundry 2024年第1期21卷 82-90页

作者： Kun Gao yan peng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

To investigate the thermal and mechanical behavior of casting wheel,a two-dimensional thermoelastic-plastic finite element model was used to predict the temperature,stress and distortion distribution of the casting wheel during the wheel and belt continuous casting process.The effects of grinding thickness and casting speed on the thermal and mechanical behaviors of the center of the hot face of the casting wheel were discussed in detail.In each rotation,the casting wheel passes through four different spray zones.The results show that the temperature distribution of the casting wheel in different spray zones is similar,the temperature of the hot face is the highest and the temperature reaches the peak in the spray zoneⅢ.The stress and distortion depend on the temperature distribution,and the maximum stress and distortion of the hot face are 358.2 MPa and 1.82 mm,respectively.The temperature at the center of the hot face decreases with increasing grinding thickness and increases with increasing casting speed.

关键词： casting wheel finite element model grinding thickness casting speed hot face spray zones

Numerical simulation of fluid flow and free surface fluctuations during wheel and belt casting process

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1117-1126页

作者： Kun Gao yan peng National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina

The unstable fluid flow and severe free surface fluctuations in the wheel and belt caster can affect the quality of the cast bar.The lower level height tends to entrap inclusions in the molten metal.On the other hand,the higher level height makes the production process more dangerous due to the overflow of high temperature fluid from the mold.A computational model of the molten metal pouring process was established.The transient fluid flow and free surface fluctuations behavior were calculated using the three-dimensional large eddy simulation model and the volume of fluid model.The results show that the flow velocity of the main jet gradually decreases under the influence of the low kinetic energy fluid in the mold.There is an obvious oscillation in the tail of the jet,while the flow field is asymmetric in space.The jet is closer to the inside radius side due to the Coanda effect,and there is a recirculation zone on the inside radius and the outside radius respectively,according to the 10 s time-averaged results.Compared with the industrial observation and simulation results,the shape of the free surface is a wave that varies with time.In addition,the free surface height is lowest and the flow velocity is highest in the region near the jet.

关键词： Fluid flow Free surface Wheel and belt caster Large eddy simulation Volume of fluid method

Simple preparation of C(CS)/g-C_(3)N_(4)/Co carbon aerogel and its catalytic performance for ammonium perchlorate

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Defence Technology（防务技术） 2024年第3期33卷 186-196页

作者： Yujie yan Bo Jin Rufang peng State Key Laboratory of Environment-friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologyMianyang621010China

Biomass chitosan(CS)was used as a template,graphitic phase carbon nitride(g-C_(3)N_(4))with high nitrogen content and certain catalytic activity was used as a dopant,and nano-transition metal cobalt(Co)was used as a catalytic center point.The carbon aerogel(C(CS)/g-C_(3)N_(4)/Co)with a three-dimensional network-like structure was prepared by assembling the three materials through experimental operations such as freeze-drying and high-temperature carbonization.It was demonstrated by scanning and transmission characterization that the CS in the carbon aerogel could provide more active sites for the cobalt nanoparticles,and the doping of graphite-phase carbon nitride as a template dispersed the cobalt nanoparticles and changed the conductivity of the CS.To investigate the catalytic effect of carbon aerogel on ammonium perchlorate(AP),it was investigated by differential thermal analyzer and TG thermal analysis.This carbon aerogel was very effective in catalyzing AP,and the 10 wt% content of the catalyst reduced the AP pyrolysis peak from 703.9 to 595.5 K.And to further investigate the synergistic effect of the three materials,further carbon aerogels such as C(CS)/Co,g-C_(3)N_(4)/Co were prepared and applied to catalyze AP,and the same ratio reduced the AP pyrolysis peak by 98.1℃ and 97.7℃.This result indicates a synergistic effect of the assembly of the three materials.

关键词： g-C_(3)N_(4) Chitosan Co Ammonium perchlorate Pyrolysis kinetics

Paracrine function amplifies pro-tumor electrochemical signal within neuron-glioma synapses

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Science China(Life Sciences) 2024年第6期67卷 1318-1320页

作者： yan Hu Peishan Hu Xiaozhong peng Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE State Key Laboratory of BiotherapyWest China Second University HospitalSichuan UniversityChengdu 610041China Guangdong Institute of Gastroenterology Department of General SurgeryGuangdong Provincial Key Laboratory of Colorectal and Pelvic Floor DiseasesThe Sixth Affiliated HospitalSun Yat-sen UniversityGuangzhou 510655China Department of Molecular Biology and Biochemistry Institute of Basic Medical SciencesMedical Primate Research CenterNeuroscience CenterChinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijing 100730China State Key Laboratory of Respiratory Health and Multimorbidity Institute of Basic Medical Sciences Chinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijing 100730China Institute of Laboratory Animal Science Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China

Neuronal activity plays a pivotal role in various physiological processes,including tissue development,homeostasis,and adaptability.Advances in recent years have improved our understanding of neuronal activity in brain cancers,such as glioblastoma(GBM)and diffuse midline gliomas(DMG),which are among the most prevalent and lethal cancers affecting children and adults.Generally,the neurons regulate brain cancers via two routes.

关键词： glioma homeostasis function

Cooperative control for heterogeneous multi-agent systems: progress, applications, and challenges

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Science China(Information Sciences) 2024年第5期67卷 318-320页

作者： Bing yan peng SHI Jonathon CHAMBERS School of Electrical and Mechanical Engineering Faculty of Science Engineering and TechnologyThe University of Adelaide School of Engineering College of Science and Engineering University of Leicester

Cooperative control for heterogeneous multi-agent systems(MASs) is a critical and rapidly evolving field in modern automation and robotics. Characterized by the integration of agents with diverse capabilities and func... 详细信息

关键词： Multi agent systems

Enhanced and asymmetric signatures of hybridization at climatic margins: Evidence from closely related dioecious fig species

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Plant Diversity 2024年第2期46卷 181-193页

作者： Jian-Feng Huang Clive T.Darwell yan-Qiong peng CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China National Center for Genetic Engineering and Biotechnology(BIOTEC) 113 Thailand Science ParkPhahonyothin RoadKhlong NuengKhlong LuangPathum Thani 12120Thailand

Hybridization plays a significant role in biological evolution. However, it is not clear whether ecological contingency differentially influences likelihood of hybridization, particularly at ecological margins where parental species may exhibit reduced fitnesses. Moreover, it is unknown whether future ecosystem change will increase the prevalence of hybridization. Ficus heterostyla and F. squamosa are closely related species co-distributed from southern Thailand to southwest China where hybridization, yielding viable seeds, has been documented. As a robust test of ecological factors driving hybridization, we investigated spatial hybridization signatures based on nuclear microsatellites from extensive population sampling across a widespread contact range. Both species showed high population differentiation and strong patterns of isolation by distance. Admixture estimates exposed asymmetric interspecific gene flow.Signatures of hybridization increase significantly towards higher latitude zones, peaking at the northern climatic margins. Geographic variation in reproductive phenology combined with ecologically challenging marginal habitats may promote this phenomenon. Our work is a first systematic evaluation of such patterns in a comprehensive, latitudinally-based clinal context, and indicates that tendency to hybridize appears strongly influenced by environmental conditions. Moreover, that future climate change scenarios will likely alter and possibly augment cases of hybridization at ecosystem scales.

关键词： Hybridization Heterospecific visitation Fig Pollinator wasp Asymmetric gene flow

HIF-1α signaling: Essential roles in tumorigenesis and implications in targeted therapies

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Genes & Diseases 2024年第1期11卷 234-251页

作者： yan Zhao Cheng Xing Yating Deng Can Ye Hongling peng Department of Hematology The Second Xiangya HospitalCentral South UniversityChangshaHunan 410011China Hunan Key Laboratory of Tumor Models and Individualized Medicine The Second Xiangya HospitalCentral South UniversityChangshaHunan 410011China Hunan Engineering Research Center of Cell Immunotherapy for Hematopoietic Malignancies The Second Xiangya HospitalCentral South UniversityChangshaHunan 410011China

The hypoxic microenvironment is an essential characteristic of most malignant tu-mors.Notably,hypoxia-inducible factor-1 alpha(HIF-1a)is a key regulatory factor of cellular adaptation to hypoxia,and many critical pathways are correlated with the biological activity of organisms via HIF-1a.In the intra-tumoral hypoxic environment,HIF-1αis highly expressed and contributes to the malignant progression of tumors,which in turn results in a poor prog-nosis in patients.Recently,it has been indicated that HiF-1αinvolves in various critical pro-cesses of life events and tumor development via regulating the expression of HiF-1a target genes,such as cell proliferation and apoptosis,angiogenesis,glucose metabolism,immune response,therapeutic resistance,etc.Apart from solid tumors,accumulating evidence has re-vealed that HiF-1αis also closely associated with the development and progression of hemato-logical malignancies,such as leukemia,lymphoma,and multiple myeloma.Targeted inhibition of HiF-1a can facilitate an increased sensitivity of patients with malignancies to relevant ther-apeutic agents.In the review,we elaborated on the basic structure and biological functions of HIF-1a and summarized their current role in various malignancies.It is expected that they will have future potential fortargeted therapy.

关键词： Angiogenesis Hematological malignancies Hypoxia-inducible factor-1 alpha(HIF-1α) Immune escape Targeted therapy