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Measures to Enhance the Surveillance System and the Situation of Offenses Seen in Maritime Fishing:The National Fisheries Surveillance and Police Center(CNSP)in Guinea
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作者 Daouda Konate Pascal Bilivogui +1 位作者 Abdoulaye Bah Sekouba Mara 《Journal of Environmental Science and Engineering(B)》 2025年第1期23-35,共13页
This work’s goal was to compile a list of fishing-related violations in order to suggest ways to enhance the surveillance system.In order to accomplish this goal,the following approach was used:Executive consultation... This work’s goal was to compile a list of fishing-related violations in order to suggest ways to enhance the surveillance system.In order to accomplish this goal,the following approach was used:Executive consultation and archive exploitation;surveillance agent survey;surveillance system identification and description;identification of offenses and fleet involved in the Guinean exclusive and economic area in recent years;identification and categorization of offense causes;surveillance system evaluation;and suggestion for enhanced surveillance system measures.Monitoring of this strategy showed that:fishing operating zones,administrative paperwork,and fishing gear are all linked to the infractions committed in the Guinean exclusive and economic zone.Records show that there were 308 boardings between 2006 and 2021.IP(Intellectual Property)infringement rates are 59%,Motorized Artisanal Fishing is 25%,and Semi-industrial fishing is 16%.In Motorized Artisanal Fishing,the Guineans have committed 33,the Senegalese have committed 23,and the Leonese have committed 18.In Semi-industrial fishing,the Chinese have committed 17 and the Senegalese have committed 16.According to the stakeholder survey,Vessal Monitoring System monitored 79 vessels in industrial fishing and 49 in Semi-industrial fishing in 2021.Registration certificates,personnel,rescue gear,gross tonnage,coastal state fishing authority,and maritime radio license are typically the primary documents examined at sea.From 2006 to 2022,a total of 135 fleets-80 demersal trawlers,7 cephalopod boats,21 shrimp boats,22 pelagic trawlers,and 5 cargo ships-were implicated in violations in the Guinean exclusive and economic area.By integrating the automatic identification system and Vessal Monitoring systems for fisheries surveillance,establishing a marking system for fishing gear,investing in highly effective launches,and protecting the privacy of patrol activities,Guinea’s surveillance system might be improved more effectively. 展开更多
关键词 Offenses marine fishing surveillance system BOARDING
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Vascular plant diversity and distribution pattern in Tajikistan:A global hotspot of diversity
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作者 ZHOU Yixin MA Suliya +7 位作者 LI Wenjun Parvina KURBONOVA Mariyo BOBOEV LI Yufan Hikmat HISORIEV MA Keping YANG Weikang ZHANG Yuanming 《Regional Sustainability》 2026年第1期37-53,共17页
Tajikistan represents a core region of the biodiversity hotspot in Central Asian mountains and has exceptional vascular plant diversity.However,the species diversity of the country faces urgent conservation challenges... Tajikistan represents a core region of the biodiversity hotspot in Central Asian mountains and has exceptional vascular plant diversity.However,the species diversity of the country faces urgent conservation challenges.There has been a lack of a comprehensive and multidimensional assessment to inform strategic conservation planning.Therefore,this study integrated 4 key biodiversity indices including species richness(SR),phylogenetic diversity(PD),threatened species richness(TSR),and endemic species richness(ESR)to map species diversity distribution patterns,identify conservation gaps,and elucidate their effects of climatic factors.This study revealed that species diversity shows a clear trend of decreasing from the western region to the eastern region of Tajikistan.The central–western mountains(specifically the Gissar-Darvasian and Zeravshanian regions)emerge as irreplaceable biodiversity hotspots.However,we found a severe spatial mismatch between these priority areas and the existing protected areas(PAs).Protection coverage for all hotspots was alarmingly low,ranging from 31.00%to 38.00%.Consequently,a critical 64.80%of integrated priority areas fall outside of the current PAs,representing a major conservation gap.This study identified precipitation seasonality and isothermality as the principal drivers,collectively explaining over 50.00%of the diversity variation and suggesting high vulnerability to hydrological shifts.Furthermore,we detected significant geographic sampling bias in the public biodiversity databases,with the most critical hotspot being systematically under-sampled.This study provides a robust scientific basis for conservation action,highlighting the urgent need to strategically expand PAs in the under-protected southwestern region and to mitigate critical sampling gaps through targeted data digitization and field surveys.These measures are indispensable for securing Tajikistan’s unique biodiversity and achieving the Kunming-Montreal Global Biodiversity Framework Target 3(“30×30 Protection”). 展开更多
关键词 Vascular plant Species diversity Distribution pattern Conservation gaps TAJIKISTAN
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GFAP expression in the optic nerve and increased Н2S generation in the integration centers of the rainbow trout(Oncorhynchus mykiss) brain after unilateral eye injury 被引量:2
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作者 Evgeniya V.Pushchina Anatoly A.Varaksin +1 位作者 Dmitry K.Obukhov Igor M.Prudnikov 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第10期1867-1886,共20页
Hydrogen sulfide(H2S)is considered as a protective factor against cardiovascular disorders.However,there are few reports on the effects of H2S in the central nervous system during stress or injury.Previous studies on ... Hydrogen sulfide(H2S)is considered as a protective factor against cardiovascular disorders.However,there are few reports on the effects of H2S in the central nervous system during stress or injury.Previous studies on goldfish have shown that astrocytic response occurs in the damaged and contralateral optic nerves.Glial fibrillary acidic protein(GFAP)concentration in the optic nerves of rainbow trout has not been measured previously.This study further characterized the astrocytic response in the optic nerve and the brain of a rainbow trout(Oncorhynchus mykiss)after unilateral eye injury and estimated the amount of H2S-producing enzyme cystathionineβ-synthase(CBS)in the brain of the rainbow trout.Within 1 week after unilateral eye injury,a protein band corresponding to a molecular weight of 50 kDa was identified in the ipsi-and contralateral optic nerves of the rainbow trout.The concentration of GFAP in the injured optic nerve increased compared to the protein concentration on the contralateral side.The results of a quantitative analysis of GFAP+cell distribution in the contralateral optic nerve showed the largest number of GFAP+cells and fibers in the optic nerve head.In the damaged optic nerve,patterns of GFAP+cell migration and large GFAP+bipolar activated astrocytes were detected at 1 week after unilateral eye injury.The study of H2S-producing system after unilateral eye injury in the rainbow trout was conducted using enzyme-linked immunosorbent assay,western blot analysis,and immunohistochemistry of polyclonal antibodies again st CBS in the integrative centers of the brain:telencephalon,optic tectum,and cerebellum.Enzyme-linked immunosorbent assay results showed a 1.7-fold increase in CBS expression in the rainbow trout brain at 1 week after unilateral eye injury compared with that in intact animals.In the ventricular and subventricular regions of the rainbow trout telencephalon,CBS+radial glia and neuroepithelial cells were identified.After unilateral eye injury,the number of CBS+neuroepithelial cells in the pallial and subpallial periventricular regions of the telencephalon increased.In the optic tectum,unilateral eye injury led to an increase in CBS expression in radial glial cells;simultaneously,the number of CBS+neuroepithelial cells decreased in intact animals.In the cerebellum of the rainbow trout,neuroglial interrelationships were revealed,where H2S was released,apparently,from astrocyte-like cells.The organization of H2S-producing cell complexes suggests that,the amount of glutamate produced in the rainbow trout cerebellum and its reuptake was controlled by astrocyte-like cells,reducing its excitotoxicity.In the dorsal matrix zone and granular eminences of the rainbow trout cerebellum,CBS was expressed in neuroepithelial cells.After unilateral eye injury,the level of CBS activity increased in all parts of the cerebellum.An increase in the number of H2S-producing cells was a response to oxidative stress after unilateral eye injury,and the overproduction of H2S in the cerebellum occurred to neutralize reactive oxygen species,providing the cells of the rainbow trout cerebellum with a protective effect.A structural reorganization in the dorsal matrix zone,associated with the appearance of an additional CBS+apical zone,and a decrease in the enzyme activity in the dorsal matrix zone,was revealed in the zones of constitutive neurogenesis.All experiments were approved by the Commission on Biomedical Ethics,A.V.Zhirmunsky National Scientific Center of Marine Biology(NSCMB),Far Eastern Branch,Russian Academy of Science(FEB RAS)(approval No.1)on July 31,2019. 展开更多
关键词 astrocyte-like cells glial fibrillary acidic protein hydrogen sulfide neuroepithelial cells NEUROPROTECTION radial glial cells rainbow trout(Oncorhynchus mykiss) reactive oxygen species unilateral eye injury
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Patients with functional bowel disorder have disaccharidase deficiency:A single-center study from Russia 被引量:1
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作者 Saria Dbar Olga Akhmadullina +11 位作者 Elena Sabelnikova Nikolai Belostotskiy Asfold Parfenov Svetlana Bykova Sergey Bakharev Elena Baulo Alexandra Babanova Lilia Indeykina Tatyana Kuzmina Tatiana Kosacheva Aleksey Spasenov Alina Makarova 《World Journal of Clinical Cases》 SCIE 2021年第17期4178-4187,共10页
BACKGROUND Functional bowel disorder(FBD)may be caused by a decrease in disaccharidase activity.Thus,the timely diagnosis of disaccharidase deficiency could lead to a better prognosis in patients with this condition.A... BACKGROUND Functional bowel disorder(FBD)may be caused by a decrease in disaccharidase activity.Thus,the timely diagnosis of disaccharidase deficiency could lead to a better prognosis in patients with this condition.AIM To determine the potential value of intestinal disaccharidases glucoamylase,maltase,sucrase,and lactase in understanding the etiology and pathogenesis of FBD.METHODS A total of 82 FBD patients were examined.According to the Rome IV criteria(2016),23 patients had diarrhea-predominant irritable bowel syndrome(IBS),33 had functional diarrhea,10 had constipation-predominant IBS,4 had functional constipation,and 12 had mixed IBS.The Dahlqvist method was used to measure disaccharidase activity in the brush-border membrane of mature enterocytes of the small intestine,in duodenal biopsies obtained during esophagogastroduodenoscopy.RESULTS Lactase deficiency was detected in 86.5%of patients,maltase deficiency in 48.7%,sucrase deficiency in 50%,and glucoamylase deficiency in 84.1%.The activities of all enzymes were reduced in 31.7%of patients,and carbohydrase deficiency was detected in 63.5%of patients.The low activity of enzymes involved in membrane digestion in the small intestine was found in 95.2%of patients.CONCLUSION In 78 of the 82 patients with FBD,gastrointestinal symptoms were associated with disaccharidase deficiency. 展开更多
关键词 Functional bowel disorder Irritable bowel syndrome Disaccharidase deficiency Maltase deficiency Sucrase deficiency Lactase deficiency
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New Index for Quantifying an Individual's Scientific Research Output
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作者 Mahmoud Abdel-Aty 《Computer Technology and Application》 2014年第1期44-50,共7页
Classifying researchers' work according to the quality of their publications rather than the quantity of their publications is an important issue. To this end we introduce a new measure, the "percentage range" or A... Classifying researchers' work according to the quality of their publications rather than the quantity of their publications is an important issue. To this end we introduce a new measure, the "percentage range" or A-index, which provides a qualitative evaluation of a researchers' productivity. The percentage range depends to a great extent on the number of single-author published papers and their citations. It is to be a new index to be considered along with the h-index. The combined factors have the advantage of making clearer the innovation of the individual authors. The resultant percentage range gives a reduced impact on its numerical value for authors who gain citations by adding their names on multi-author papers. It is shown that various dimensions of ethical integrity and originality are clarified by the new index. The important scenarios arising from this analysis are demonstrated with examples, The great differences between the new percentage range and old h-index come from the percentage range's emphasis on considering the whole work of an author, including the significance of the author's single-author papers as opposed to multiple-author contributions. This emphasis is demonstrated. 展开更多
关键词 H-INDEX impact factor research output.
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Research and practice of marine scientific data security governance
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作者 FU Yu TONG Xin +2 位作者 CAO Shengwen XU Mogeng HE Long 《Marine Science Bulletin》 2024年第2期69-83,共15页
at present,data security has become the most urgent and primary issue in the era of digital economy.Marine scientific data security is the most urgent core issue of marine data resource management and sharing service.... at present,data security has become the most urgent and primary issue in the era of digital economy.Marine scientific data security is the most urgent core issue of marine data resource management and sharing service.This paper focuses on the analysis of the needs of marine scientific data security governance,in-depth development of marine scientific data security governance approaches and methods,and practical application in the national marine scientific data center,optimizing the existing data management model,ensuring the safety of marine scientific data,and fully releasing the data value. 展开更多
关键词 data security governance marine scientific data data sharing
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Fabrication of SnS_(2)/C_(3)N_(5), heterojunction photocatalyst for highly efficient hydrogen production and organic pollutant degradation 被引量:1
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作者 GAO Yanan SHI Ming +2 位作者 YANG Jingxuan WANG Yajie LIU Bin 《燃料化学学报(中英文)》 北大核心 2025年第3期336-347,共12页
The semiconductor photocatalysis are considered as one of the most promising candidates in hydrogen energy source and environmental remediation area.In this paper,flower-shaped SnS,is successfully combined on g-C,Ns,a... The semiconductor photocatalysis are considered as one of the most promising candidates in hydrogen energy source and environmental remediation area.In this paper,flower-shaped SnS,is successfully combined on g-C,Ns,and the well matching band structure successfully constitutes a new Type-II heterojunction.As expected,the photocatalytic hydrogen production experiment showed that the quantity of hydrogen produced on 5% SnS_(2)/C_(3)N_(5)was 922.5μmol/(g.h),which is 3.6 times higher than that of pure g-C_(3)N_(5).Meanwhile,in photocatalytic degradation of methylene blue,5%SnS2/C,Ns composite material can degrade 95% of contaminants within 40 min,showing good photocatalytic degradation performance.The mechanism study indicates that SnS_(2)/C_(3)N_(5)heterojunction improves the photogenerated charge migration rate and reduces the electron-hole recombination rate,and effectively improves the photocatalytic performance of g-C_(3)N_(5).This work provides a new idea for designing C,Ns-based heterojunctions with efficient hydrogen production and degradation performance. 展开更多
关键词 C_(3)N_(5) stannic disulfide photocatalysis hydrogen PHOTODEGRADATION
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Comparative study on the oblique water-entry of high-speed projectile based on rigid-body and elastic-plastic body model 被引量:2
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作者 Xiangyan Liu Xiaowei Cai +3 位作者 Zhengui Huang Yu Hou Jian Qin Zhihua Chen 《Defence Technology(防务技术)》 2025年第4期133-155,共23页
To examine the similarities and differences in the evolution of cavity,wetting and dynamics of a highspeed,oblique water-entry projectile with different positive angles of attack,a comparative analysis has been conduc... To examine the similarities and differences in the evolution of cavity,wetting and dynamics of a highspeed,oblique water-entry projectile with different positive angles of attack,a comparative analysis has been conducted based on the numerical results of two mathematical models,the rigid-body model and fluid-structure interaction model.In addition,the applicable scope of the above two methods,and the structural response characteristics of the projectile have also been investigated.Our results demonstrate that:(1) The impact loads and angular motion of the projectile of the rigid-body method are more likely to exhibit periodic variations due to the periodic tail slap,its range of positive angles of attack is about α<2°.(2) When the projectile undergone significant wetting,a strong coupling effect is observed among wetting,structural deformation,and projectile motion.With the applied projectile shape,it is observed that,when the projectile bends,the final wetting position is that of Part B(cylinder of body).With the occu rrence of this phenomenon,the projectile ballistics beco me completely unstable.(3) The force exerted on the lower surface of the projectile induced by wetting is the primary reason of the destabilization of the projectile traj ectory and structu ral deformation failure.Bending deformation is most likely to appear at the junction of Part C(cone of body) and Part D(tail).The safe angles of attack of the projectile stability are found to be about α≤2°. 展开更多
关键词 Fluid-structure interaction Rigid-body model Elastic-plastic model Structural deformation Impact loads Structural safety of projectile
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DI-YOLOv5:An Improved Dual-Wavelet-Based YOLOv5 for Dense Small Object Detection 被引量:1
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作者 Zi-Xin Li Yu-Long Wang Fei Wang 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期457-459,共3页
Dear Editor,This letter focuses on the fact that small objects with few pixels disappear in feature maps with large receptive fields, as the network deepens, in object detection tasks. Therefore, the detection of dens... Dear Editor,This letter focuses on the fact that small objects with few pixels disappear in feature maps with large receptive fields, as the network deepens, in object detection tasks. Therefore, the detection of dense small objects is challenging. 展开更多
关键词 small objects receptive fields feature maps detection dense small objects object detection dense objects
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Investigation on the Ice Load on a Cylinder Vertically Breaking through Model Ice Sheet from Underneath
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作者 ZHAO Wei−hang TIAN Yu−kui +3 位作者 JI Shao−peng GANG Xu−hao YU Chao−ge KONG Shuai 《船舶力学》 北大核心 2025年第6期964-975,共12页
Ice load on underwater vehicles breaking through ice covers from underneath is a significant concern for researchers in polar exploration,and the research on this problem is still in its early stages.Both mechanical e... Ice load on underwater vehicles breaking through ice covers from underneath is a significant concern for researchers in polar exploration,and the research on this problem is still in its early stages.Both mechanical experimental measurement and numerical simulation pose research challenges.This study focuses on the ice load of a cylinder structure breaking upward through the ice sheet form underneath in the Small Ice Model Basin of China Ship Scientific Research Center(CSSRC SIMB).A high-speed camera system was employed to observe the ice sheet failure during the tests,in which,with the loading position as center,local radial cracks and circumferential cracks were generated.A load sensor was used to measure the overall ice load during this process.Meanwhile,a numerical model was developed using LS-DYNA for validation and comparison.With this model,numerical simulation was conducted under various ice thicknesses and upgoing speeds to analyze the instantaneous curves of ice load.The calculation results were statistically analyzed under different working conditions to determine the influence of the factors on the ice load of the cylinder.The study explores the measurement method about ice load of objects vertically breaking through model ice sheet and is expected to provide some fundamental insights into the safety design of underwater structures operating in ice waters. 展开更多
关键词 CYLINDER model test failure mode crack propagation ice load numerical modeling
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Monitoring and Data Analysis of Mooring Tension for Floating Platforms
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作者 YANG Hua−wei ZHENG Qing−xin +2 位作者 XU Chun YANG Qi−fan JIANG Zhen−tao 《船舶力学》 北大核心 2025年第6期941-951,共11页
Mooring cable tension is a crucial parameter for evaluating the safety and reliability of a floating platform mooring system.The real-time mooring tension in an actual marine environment has always been essential data... Mooring cable tension is a crucial parameter for evaluating the safety and reliability of a floating platform mooring system.The real-time mooring tension in an actual marine environment has always been essential data that mooring system designers aim to acquire.To address the need for long-term continuous monitoring of mooring tension in deep-sea marine environments,this paper presents a mooring cable tension monitoring method based on the principle of direct mechanical measurement.The developed tension monitoring sensors were installed and applied in the mooring system of the"Yongle"scientific experimental platform.Over the course of one year,a substantial amount of in-situ tension monitoring data was obtained.Under wave heights of up to 1.24 m,the mooring tension on the floating platform reached 16.5 tons.Through frequency domain and time domain analysis,the spectral characteristics of mooring tension,including waveinduced force,slow drift force,and mooring cable elastic restoring force,were determined.The mooring cable elastic restoring force frequency was approximately half of that of the wave signal.Due to the characteristics of the hinge connection structure of the dual module floating platform,under some specific working conditions the wave-induced force was the maximum of the three different frequency forces,and restoring force was the smallest. 展开更多
关键词 floating platform mooring tension tension monitoring sensor wave frequency force drift force
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Manufacturing of lithium battery toward deep-sea environment 被引量:1
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作者 Yaohua Zhao Nan Li +4 位作者 Keyu Xie Chuan Wang Sisi Zhou Xianggong Zhang Cong Ye 《International Journal of Extreme Manufacturing》 2025年第2期310-335,共26页
The operation of deep-sea underwater vehicles relies entirely on onboard batteries.However,the extreme deep-sea conditions,characterized by ultrahigh hydraulic pressure,low temperature,and seawater conductivity,pose s... The operation of deep-sea underwater vehicles relies entirely on onboard batteries.However,the extreme deep-sea conditions,characterized by ultrahigh hydraulic pressure,low temperature,and seawater conductivity,pose significant challenges for battery development.These conditions drive the need for specialized designs in deep-sea batteries,incorporating critical aspects of power generation,protection,distribution,and management.Over time,deep-sea battery technology has evolved through multiple generations,with lithium(Li)batteries emerging in recent decades as the preferred power source due to their high energy and reduced operational risks.Although the rapid progress of Li batteries has notably advanced the capabilities of underwater vehicles,critical technical issues remain unresolved.This review first systematically presents the whole picture of deep-sea battery manufacturing,focusing on Li batteries as the current mainstream solution for underwater power.It examines the key aspects of deep-sea Li battery development,including materials selection informed by electro-chemo-mechanics models,component modification and testing,and battery management systems specialized in software and hardware.Finally,it discusses the main challenges limiting the utilization of deep-sea batteries and outlines promising directions for future development.Based on the systematic reflection on deep-sea batteries and discussion on deep-sea Li batteries,this review aims to provide a research foundation for developing underwater power tailored for extreme environmental exploration. 展开更多
关键词 manufacturing of deep-sea battery Li battery materials selection component modification and test specialized battery management system
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KHSRP promotes cancer stem cell maintenance,tumorigenesis,and suppresses anti-tumor immunity in gastric cancer 被引量:1
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作者 YARU DU ZHIHUI PEI +2 位作者 SHUQIN HU CHUANWEN LIAO SHUHAO LIU 《Oncology Research》 2025年第2期309-325,共17页
Objectives:KH-type splicing regulatory protein(KHSRP)is an RNA-binding protein involved in several cellular processes,including nuclear splicing,mRNA localization,and cytoplasmic degradation.While KHSRP’s role has be... Objectives:KH-type splicing regulatory protein(KHSRP)is an RNA-binding protein involved in several cellular processes,including nuclear splicing,mRNA localization,and cytoplasmic degradation.While KHSRP’s role has been studied in other cancers,its specific involvement in gastric cancer remains poorly understood.This study aims to explore KHSRP expression in gastric cancer and its potential effects on tumor progression and immune response.Methods:KHSRP expression in gastric cancer tissues and normal tissues was analyzed using data from The Cancer Genome Atlas(TCGA)database.The correlation between KHSRP expression,patient survival,and immune response was also assessed.Immunohistochemistry was performed to evaluate KHSRP expression in gastric cancer tissues.Gain-and loss-of-function experiments were conducted to assess KHSRP’s effects on gastric cancer cell proliferation,stemness,and migration.Furthermore,the impact of KHSRP silencing on tumor volume and immune cell infiltration was evaluated in a C3H/He mouse xenograft model.Results:KHSRP was found to be overexpressed in gastric cancer tissues compared to normal tissues,with a positive correlation to tumor stage and a negative correlation with patient prognosis.Functional assays revealed that KHSRP promotes gastric cancer cell proliferation,enhances cancer stem cell properties,and increases migratory capabilities in vitro.In vivo,KHSRP silencing led to a significant reduction in tumor volume and increased immune cell infiltration in the mouse xenograft model.Conclusions:KHSRP acts as an oncogene in gastric cancer by promoting tumorigenesis and suppressing anti-tumor immune responses.Its overexpression is associated with poor prognosis,making KHSRP a potential prognostic marker and therapeutic target in gastric cancer. 展开更多
关键词 KH-type splicing regulatory protein(KHSRP) Gastric cancer(GC) Cancer stem cell TUMORIGENESIS
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Bubble Theory and its Applications in Underwater Explosion, Marine Cavitation, and Seismic Exploration 被引量:1
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作者 Runze Xu Shiping Wang +1 位作者 Hemant J.Sagar Haikun Wang 《哈尔滨工程大学学报(英文版)》 2025年第2期255-284,共30页
Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have bee... Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have been conducted to reveal the mysteries of bubble motion and its mechanisms.These efforts have significantly advanced research in bubble dynamics,where theoretical study is an efficient method for bubble motion prediction.Since Lord Rayleigh introduced the theoretical model of single-bubble motion in incompressible fluid in 1917,theoretical studies have been pivotal in understanding bubble dynamics.This study provides a comprehensive review of the development and applicability of theoretical studies in bubble dynamics using typical theoretical bubble models across different periods as a focal point and an overview of bubble theory applications in underwater explosion,marine cavitation,and seismic exploration.This study aims to serve as a reference and catalyst for further advancements in theoretical analysis and practical applications of bubble theory across marine fields. 展开更多
关键词 Bubble theory Underwater explosion Marine cavitation Seismic exploration
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Fatigue Crack Growth Behavior of High-strength Steel for Ships
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作者 LEI Yin−hui WANG Ke +3 位作者 ZHANG Ruo−nan LI Yong−zheng QIN Chuang WEI Peng−yu 《船舶力学》 北大核心 2025年第6期952-963,共12页
As a typical steel,the fatigue of marine high-strength steels has been emphasized by scholars.In this paper,the fatigue performance and crack growth mechanism of a high-strength steel for ships are investigated by exp... As a typical steel,the fatigue of marine high-strength steels has been emphasized by scholars.In this paper,the fatigue performance and crack growth mechanism of a high-strength steel for ships are investigated by experimental methods.First,the fatigue threshold test and fatigue crack growth rate test of this high-strength steel under different stress ratios were carried out.The influence of stress ratio on the fatigue properties of this steel was analyzed.Secondly,scanning electron microscope was used to analyze the crack growth specimen section of this steel.The crack growth and failure mechanism of this steel were revealed.Finally,based on the above research results,the stress ratio effect of high-strength steel was investigated from the perspectives of crack closure and driving force.Considering the fatigue behavior in the near-threshold stage and the destabilization stage,a fatigue crack growth behavior prediction model of highstrength steel was established.The accuracy of the model was verified by test data.Moreover,the applicability of the modified model to various materials and its excellent predictive ability were verified through comparison with literature data and existing models. 展开更多
关键词 high-strength steel fatigue test load ratio effect dual-parameter-driving force prediction model
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Mechanistic Insights into N-Oleoylethanolamide-Mediated Hepatoprotection via PPAR-α
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作者 Darya Ivashkevich Arina Ponomarenko +1 位作者 Igor Manzhulo Inessa Dyuizen 《BIOCELL》 2025年第4期607-627,共21页
The high prevalence of obesity and associated nonalcoholic fatty liver disease(NAFLD)in the population determines the increased interest in identifying molecular targets for regulating the processes underlying these p... The high prevalence of obesity and associated nonalcoholic fatty liver disease(NAFLD)in the population determines the increased interest in identifying molecular targets for regulating the processes underlying these patholo-gies.The search for new endogenous bioregulators of lipid metabolism and their inclusion in therapeutic regimens for the treatment of patients is becoming a potentially promising direction in science and medicine.Oleoylethanolamide(OEA)is an endogenous lipid mediator capable of exerting multiple hypolipidemic,anti-inflammatory,and hepato-protective effects mediated by agonism with receptors of the peroxisome proliferator-activated receptor(PPAR)family(PPAR-αand PPAR-γ).This review focuses on a detailed description of the PPAR-dependent mechanisms of the hepatoprotective activity of OEA in the development of NAFLD.The main attention is paid to such topics as reduction of oxidative stress and inflammation,inhibition of liver fibrogenesis,suppression of hepatocyte death,and changes in various parameters of lipid metabolism. 展开更多
关键词 NAFLD liver inflammation N-Oleoylethanolamide OEA PPAR-Α
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Application of Wuling powder in the treatment of ulcerative colitis complicated by depression as a new therapy principle
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作者 Olga V Smirnova Aleksander Sinyakov Edward V Kasparov 《World Journal of Gastroenterology》 2025年第23期103-108,共6页
The problem of ulcerative colitis(UC)is becoming increasingly relevant due to its prevalence and combination with psychological disorders.UC is associated with alterations in the intestinal microbiocenosis as one of t... The problem of ulcerative colitis(UC)is becoming increasingly relevant due to its prevalence and combination with psychological disorders.UC is associated with alterations in the intestinal microbiocenosis as one of the factors reducing tolerance to self-antigens.In addition,patients with UC often experience anxiety,depression and other negative emotional and psychological factors aggravating the course of the underlying disease.The study presented by Wang et al shows that the traditional Chinese medicine Wuling can exert its therapeutic effect by reversing the aberrant precursor of brain-derived neurotrophic factor(BDNF)/BDNF signaling in mice with UC and depression.The combination of Wuling powder with mesalazine can exhibit an antidepressant effect and reduce intestinal inflammation.Undoubtedly,the study by Chinese authors deserves attention,and changes in the balance of precursor of BDNF/p75 neurotrophin receptor/sortilin and BDNF/tropomyosin receptor kinase B signaling may become a novel therapeutic target for clinical treatment and further development of research. 展开更多
关键词 Ulcerative colitis DEPRESSION Signaling pathways Precursor of brain-derived neurotrophic factor/p75 neurotrophin receptor/sortilin Brain-derived neurotrophic factor/tropomyosin receptor kinase B Wuling powder
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Helicobacter pylori infection as a risk factor in the development of metabolic dysfunction-associated steatotic liver disease
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作者 Olga V Smirnova Aleksander A Sinyakov Edward V Kasparov 《World Journal of Hepatology》 2025年第10期19-26,共8页
The problem of metabolic dysfunction-associated steatotic liver disease(MASLD)is becoming a non-infectious pandemic,the growth drivers of which are obesity and diabetes mellitus.According to modern concepts,MASLD deve... The problem of metabolic dysfunction-associated steatotic liver disease(MASLD)is becoming a non-infectious pandemic,the growth drivers of which are obesity and diabetes mellitus.According to modern concepts,MASLD develops and progresses as a result of the interaction of multiple genetic,environmental and adaptive factors,which include specific genetic polymorphisms(for example,the patatin-like phospholipase domain-containing protein 3 gene)and epigenetic modifications,dietary patterns(for example,high consumption of saturated fats and fructose),physical inactivity,obesity,insulin resistance,dysregulation of adipokine production,lipotoxicity,oxidative stress,intestinal microbiota dysbiosis(small intestinal bacterial overgrowth syndrome).In addition,due to the high infection rate of Helicobacter pylori(up to 80%)of people in the population,the influence of this factor on the development and progression of MASLD cannot be ruled out.Ye et al presented a study investigating the relationship between Helicobacter pylori infection and metabolic dysfunction associated with hepatic steatosis and identified prognostic factors.Certainly,the work of the Chinese authors deserves attention and further study. 展开更多
关键词 Helicobacter pylori infection Metabolic dysfunction-associated steatotic liver disease OBESITY Lipid profile Blood glucose CYTOKINES
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2D coordination polymers of transition metals as catalysts for oxygen evolution reaction
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作者 Mikhail N.Khrizanforov Anastasiia P.Samorodnova +5 位作者 Ilya A.Bezkishko Radis R.Gainullin Kirill V.Kholin Aidar T.Gubaidullin Ruslan P.Shekurov Vasili A.Miluykov 《Materials Reports(Energy)》 2025年第2期77-85,I0002,共10页
The oxygen evolution reaction(OER)is a key process in water splitting for hydrogen production,yet its sluggish kinetics pose significant challenges for catalyst development.In this work,we present the first systematic... The oxygen evolution reaction(OER)is a key process in water splitting for hydrogen production,yet its sluggish kinetics pose significant challenges for catalyst development.In this work,we present the first systematic study on isostructural 2D coordination polymers(CPs)based on 1,10-ferrocenediyl-bis(H-phosphinic)acid,with cobalt,manganese,and cadmium metals as electrocatalysts for OER.These polymers were synthesized via a facile solution reaction,yielding crystalline materials with excellent structural integrity.The electrocatalytic performance of CPs composites,prepared with carbon and phosphonium ionic liquid,was evaluated in 0.1 M KOH using a three-electrode system.Notably,the Co-and Cd-based CPs demonstrated exceptional OER activity,achieving an overpotential as low as 236–255 mV at 10 mA cm^(-2),surpassing those of many previously reported CP-based OER catalysts.Furthermore,these materials exhibited high stability over prolonged electrolysis,maintaining their activity without significant degradation.This work not only introduces a new class of ferrocenyl phosphinatebased CPs as highly active and durable OER catalysts but also provides valuable insights into their structureactivity relationships,paving the way for future advancements in electrocatalysis. 展开更多
关键词 Oxygen evolution reaction 2D coordination polymers Ferrocenyl phosphinate ligands ELECTROCATALYSIS Water splitting Surface morphology OVERPOTENTIAL Catalytic stability
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Ecological state of the natural and agricultural phytocenoses as the marker of ecosystem services:Taking into account differences in natural and anthropogenic conditions under global climate change
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作者 SARGSYAN Karine Sh. LARIONOV Maxim Viktorovich +3 位作者 TOVMASYAN Gagik A. GHARAKHANYAN Karen A. YEGHIAZARYAN Argishti G. GALSTYAN Meruzhan H. 《Journal of Geographical Sciences》 2025年第11期2335-2362,共28页
The results of the 2022-2025 study conducted for the vulnerability assessment of pastures and for the development of improvement measures on the degraded land sections in the arid and semi-arid provinces of the Caucas... The results of the 2022-2025 study conducted for the vulnerability assessment of pastures and for the development of improvement measures on the degraded land sections in the arid and semi-arid provinces of the Caucasus under the global climate change conditions are introduced in the current article.The main goal of our scientific work is to study and assess the current ecological and resource state of natural phytocenoses,pastures and hayfields in the arid and semi-arid landscapes under climate change.The paper presents the results of determining the areas and levels of degradation of the natural biogeocenoses and biogeocenoses of the pastures and hayfields in the mountain and highland landscapes.The results were obtained using remote sensing,field and laboratory studies and analyses.The conducted studies have revealed that along 34,174.5 ha pasture and 1342.0 meadows areas of the pastures at the Areni,Yeghegis,Yeghegnadzor and Vayq consolidated administrative territories situated in the arid and semi-arid zones of the Vayots Dzor Region high degradation was recorded in about 6508 hectares of pasture and 407 hectares of meadows areas,which is related to irregular and uncontrolled economic mismanagement of the local population and global climate change.To improve the ecological condition,accessibility and quality of ecosystem services of the pastures,hayfields and natural meadows,comprehensive restoration bioecological and agrotechnical measures have been proposed.They are aimed at improving the air,water and nutrient regimes of soils,at their bioprotection,as well as at the general increase in area and at improving the economic characteristics of the vegetation cover.Such measures on the ecosystem basis are appropriate in the context of enriching the qualitative composition of plants with useful ecological and economic bioecological characteristics,taking into account the characteristics of landscapes,weather and climatic conditions,and agricultural opportunities. 展开更多
关键词 natural meadows PASTURES hayfields mountain and highland landscapes arid and semi-arid areas resources of natural phytocenoses and lands remote sensing NDVI field ecological research state of phytocenoses soil condition degradation levels the Caucasus global climate change
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