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等离子体技术制备具有亚微米颗粒结构的球化W-Cu伪合金微粉
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作者 A.V.SAMOKHIN N.V.ALEKSEEV +4 位作者 A.A.DOROFEEV A.A.FADEEV M.A.SINAYSKIY I.D.ZAVERTIAEV Y.V.GRIGORIEV 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第2期592-603,共12页
采用复杂多级方法研究并证实制备具有亚微米/纳米级内部结构的球形W-Cu复合微粉的可能性。首先,采用等离子体化学合成法制备具有核壳结构的W-Cu纳米粉末(W核及Cu壳)。然后,将W-Cu纳米粉末与蔗糖的水悬浮液进行喷雾干燥,形成25~63μm的微... 采用复杂多级方法研究并证实制备具有亚微米/纳米级内部结构的球形W-Cu复合微粉的可能性。首先,采用等离子体化学合成法制备具有核壳结构的W-Cu纳米粉末(W核及Cu壳)。然后,将W-Cu纳米粉末与蔗糖的水悬浮液进行喷雾干燥,形成25~63μm的微粒,收率为50%。最后,用热等离子体射流处理由纳米粉末组成的微粒,形成致密的球形W-Cu颗粒。成品粉末的球化度为90%~95%,体积密度为8.1 g/cm^(3),流动性约为12 s/50 g,杂质中O、C和H的含量(质量分数)分别为0.7%、0.02%~0.2%和0.03%~0.05%。 展开更多
关键词 W-CU复合材料 等离子体化学合成 造粒 等离子体球化 纳米颗粒 微粒 微粉
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Buckling Properties of Water-Drop-Shaped Pressure Hulls with Various Shape Indices Under Hydrostatic External Pressure
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作者 DING Xiao-de ZHANG Jian +2 位作者 WANG Fang JIAO Hui-feng WANG Ming-lu 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期1-17,共17页
The water-drop-shaped pressure hull has a good streamline,which has good application prospect in the underwater observatory.Therefore,this study conducted analytical,experimental and numerical investigation of the buc... The water-drop-shaped pressure hull has a good streamline,which has good application prospect in the underwater observatory.Therefore,this study conducted analytical,experimental and numerical investigation of the buckling properties of water-drop-shaped pressure hulls under hydrostatic pressure.A water-drop experiment was conducted to design water-drop-shaped pressure hulls with various shape indices.The critical loads for the water-drop-shaped pressure hulls were resolved by using Mushtari’s formula.Several numerical simulations including linear buckling analysis and nonlinear buckling analysis including eigenmode imperfections were performed.The results indicated that the critical loads resolved by Mushtari's formula were in good agreement with the linear buckling loads from the numerical simulations.This formula can be extended to estimate the buckling capacity of water-drop-shaped pressure hulls.In addition,three groups of pressure hulls were fabricated by using stereolithography,a rapid prototyping technique.Subsequently,three groups of the pressure hulls were subjected to ultrasonic measurements,optical scanning,hydrostatic testing and numerical analysis.The experimental results were consistent with the numerical results.The results indicate that the sharp end of the water-drop-shaped pressure hulls exhibited instability compared with the blunt end.This paper provides a new solution to the limitations of experimental studies on the water-drop-shaped pressure hulls as well as a new configuration and evaluation method for underwater observatories. 展开更多
关键词 BUCKLING pressure hull water drop underwater observatory
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基于分叉传递矩阵法的多跨连续刚构桥桥墩有效长度系数
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作者 康厚军 郭忠 +2 位作者 张晓宇 苏潇阳 丛云跃 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第2期542-557,共16页
桥墩的有效长度系数对桥墩的稳定性和强度十分重要。为解决桥墩的稳定性问题,本文建立了一种便于采用传递矩阵法求解的新颖力学模型,并基于该方法计算了多跨连续刚构桥的有效长度系数。首先,建立n跨刚构桥的一般力学模型,并利用传递矩... 桥墩的有效长度系数对桥墩的稳定性和强度十分重要。为解决桥墩的稳定性问题,本文建立了一种便于采用传递矩阵法求解的新颖力学模型,并基于该方法计算了多跨连续刚构桥的有效长度系数。首先,建立n跨刚构桥的一般力学模型,并利用传递矩阵法推导了其在考虑自重荷载情况下的平面内稳定特征方程,进而求得弹性屈曲载荷和有效长度系数,并将其与有限元法得到的结果进行对比,从而验证所提理论和方法的正确性。其次,研究了用碳纤维增强聚合物和超高性能混凝土加固桥墩时,桥墩有效长度系数的变化规律。最后,探讨了边跨与中跨之比、桥面梁刚度以及桥墩刚度对桥墩有效长度系数的影响。结果表明,增强整体结构刚度比增强局部刚度对提高稳定性更有效,桥梁边跨和中跨跨度对有效长度系数的影响较大。同时,还观察到碳纤维增强聚合物加固高度改变时,桥墩有效长度系数变化曲线产生了独特的双峰效应。 展开更多
关键词 有效长度系数 面内稳定性 桥墩 传递矩阵法 刚构桥
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Application of CFD and FEA Coupling to Predict Structural Dynamic Responses of A Trimaran in Uni-and Bi-Directional Waves
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作者 LIAO Xi-yu XIA Jin-song +4 位作者 CHEN Zhan-yang TANG Qin ZHAO Nan ZHAO Wei-dong GUI Hong-bin 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期81-92,共12页
To predict the wave loads of a flexible trimaran in different wave fields,a one-way interaction numerical simulation method is proposed by integrating the fluid solver(Star-CCM+)and structural solver(Abaqus).Differing... To predict the wave loads of a flexible trimaran in different wave fields,a one-way interaction numerical simulation method is proposed by integrating the fluid solver(Star-CCM+)and structural solver(Abaqus).Differing from the existing coupled CFD-FEA method for monohull ships in head waves,the presented method equates the mass and stiffness of the whole ship to the hull shell so that any transverse and longitudinal section stress of the hull in oblique waves can be obtained.Firstly,verification study and sensitivity analysis are carried out by comparing the trimaran motions using different mesh sizes and time step schemes.Discussion on the wave elevation of uni-and bi-directional waves is also carried out.Then a comprehensive analysis on the structural responses of the trimaran in different uni-directional regular wave and bi-directional cross sea conditions is carried out,respectively.Finally,the differences in structural response characteristics of trimaran in different wave fields are studied.The results show that the present method can reduce the computational burden of the two-way fluid-structure interaction simulations. 展开更多
关键词 CFD-FEA fluid-structure coupling structural responses TRIMARAN bi-directional cross sea
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In situ direct reprogramming of astrocytes to neurons via polypyrimidine tract-binding protein 1 knockdown in a mouse model of ischemic stroke
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作者 Meng Yuan Yao Tang +2 位作者 Tianwen Huang Lining Ke En Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2240-2248,共9页
In situ direct reprogramming technology can directly convert endogenous glial cells into functional neurons in vivo for central nervous system repair. Polypyrimidine tract-binding protein 1(PTB) knockdown has been sho... In situ direct reprogramming technology can directly convert endogenous glial cells into functional neurons in vivo for central nervous system repair. Polypyrimidine tract-binding protein 1(PTB) knockdown has been shown to reprogram astrocytes to functional neurons in situ. In this study, we used AAV-PHP.e B-GFAP-sh PTB to knockdown PTB in a mouse model of ischemic stroke induced by endothelin-1, and investigated the effects of GFAP-sh PTB-mediated direct reprogramming to neurons. Our results showed that in the mouse model of ischemic stroke, PTB knockdown effectively reprogrammed GFAP-positive cells to neurons in ischemic foci, restored neural tissue structure, reduced inflammatory response, and improved behavioral function. These findings validate the effectiveness of in situ transdifferentiation of astrocytes, and suggest that the approach may be a promising strategy for stroke treatment. 展开更多
关键词 astrocyte in situ direct reprogramming ischemic stroke miR-30 based shRNA neuron polypyrimidine tract-binding protein 1 TRANSDIFFERENTIATION
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Image Splicing Forgery Detection Using Feature-Based of Sonine Functions and Deep Features
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作者 Ala’a R.Al-Shamasneh Rabha W.Ibrahim 《Computers, Materials & Continua》 SCIE EI 2024年第1期795-810,共16页
The growing prevalence of fake images on the Internet and social media makes image integrity verification a crucial research topic.One of the most popular methods for manipulating digital images is image splicing,whic... The growing prevalence of fake images on the Internet and social media makes image integrity verification a crucial research topic.One of the most popular methods for manipulating digital images is image splicing,which involves copying a specific area from one image and pasting it into another.Attempts were made to mitigate the effects of image splicing,which continues to be a significant research challenge.This study proposes a new splicing detectionmodel,combining Sonine functions-derived convex-based features and deep features.Two stages make up the proposed method.The first step entails feature extraction,then classification using the“support vector machine”(SVM)to differentiate authentic and spliced images.The proposed Sonine functions-based feature extraction model reveals the spliced texture details by extracting some clues about the probability of image pixels.The proposed model achieved an accuracy of 98.93% when tested with the CASIA V2.0 dataset“Chinese Academy of Sciences,Institute of Automation”which is a publicly available dataset for forgery classification.The experimental results show that,for image splicing forgery detection,the proposed Sonine functions-derived convex-based features and deep features outperform state-of-the-art techniques in terms of accuracy,precision,and recall.Overall,the obtained detection accuracy attests to the benefit of using the Sonine functions alongside deep feature representations.Finding the regions or locations where image tampering has taken place is limited by the study.Future research will need to look into advanced image analysis techniques that can offer a higher degree of accuracy in identifying and localizing tampering regions. 展开更多
关键词 Image forgery image splicing deep learning Sonine functions
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Comprehensive analysis of the gut microbiome and posttranslational modifications elucidates the route involved in microbiota-host interactions
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作者 Hai-Yang Wang Lan-Xiang Liu +8 位作者 Xue-Yi Chen Yang-Dong Zhang Wen-Xia Li Wen-Wen Li Lian Wang Xiao-Long Mo Hong Wei Ping Ji Peng Xie 《Zoological Research》 SCIE CSCD 2024年第1期95-107,共13页
The gut microbiome interacts with the host to maintain body homeostasis,with gut microbial dysbiosis implicated in many diseases.However,the underlying mechanisms of gut microbe regulation of host behavior and brain f... The gut microbiome interacts with the host to maintain body homeostasis,with gut microbial dysbiosis implicated in many diseases.However,the underlying mechanisms of gut microbe regulation of host behavior and brain functions remain unclear.This study aimed to elucidate the influence of gut microbiota on brain functions via post-translational modification mechanisms in the presence or absence of bacteria without any stimulation.We conducted succinylome analysis of hippocampal proteins in germ-free(GF)and specific pathogen-free(SPF)mice and metagenomic analysis of feces from SPF mice.These results were integrated with previously reported hippocampal acetylome and phosphorylome data from the same batch of mice.Subsequent bioinformatics analyses revealed 584 succinylation sites on 455 proteins,including 54 up-regulated succinylation sites on 91 proteins and 99 down-regulated sites on 51 proteins in the GF mice compared to the SPF mice.We constructed a panoramic map of gut microbiota-regulated succinylation,acetylation,and phosphorylation,and identified cross-talk and relative independence between the different types of post-translational modifications in modulating complicated intracellular pathways.Pearson correlation analysis indicated that 13 taxa,predominantly belonging to the Bacteroidetes phylum,were correlated with the biological functions of post-translational modifications.Positive correlations between these taxa and succinylation and negative correlations between these taxa and acetylation were identified in the modulation of intracellular pathways.This study highlights the hippocampal physiological changes induced by the absence of gut microbiota,and proteomic quantification of succinylation,phosphorylation,and acetylation,contributing to our understanding of the role of the gut microbiome in brain function and behavioral phenotypes. 展开更多
关键词 Gut microbiota Hippocampal protein Post-translational modifications SUCCINYLATION ACETYLATION PHOSPHORYLATION
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Limb Lengthening and Reconstruction Society orthopedic surgeons in the United States:An analysis of geographical distribution,academic,leadership,and demographic characteristics
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作者 Amir Human Hoveidaei Reza Niakan +2 位作者 Seyed Hossein Hosseini-Asl Abijith Annasamudram Janet D Conway 《World Journal of Orthopedics》 2024年第2期147-155,共9页
BACKGROUND The Limb Lengthening and Reconstruction Society(LLRS)is a premier orthopedic specialty organization that promotes limb reconstruction for all ages.LLRS membership characteristics,however,are poorly reported... BACKGROUND The Limb Lengthening and Reconstruction Society(LLRS)is a premier orthopedic specialty organization that promotes limb reconstruction for all ages.LLRS membership characteristics,however,are poorly reported.This study delineates orthopedic surgeon LLRS members’demographic traits,academic achievement,leadership attainment,and geographical distribution across the United States.AIM To inform aspiring orthopedic professionals,as well as to promote growth and diversity in both the LLRS organization and overarching field.METHODS This cross-sectional study examined United States LLRS members’academic,leadership,demographic,and geographical attributes.After reviewing the 2023 LLRS member directory,Google search results were matched to the listings and appended to the compiled data.Sex and ethnicity were evaluated visually utilizing retrieved images.The Hirsch index(H-index)of academic activity,residency and fellowship training,other graduate degrees,leadership positions,practice type(academic or non-academic),and spoken languages were categorized.LLRS members per state and capita determined geographic distribution.The Mann Whitney U test was applied to compare H-index between males and females,as well as to assess member differences pertaining to affiliation with academic vs non-academic practice facilities.RESULTS The study included 101 orthopedic surgeons,78(77.23%)Caucasian and 23(22.77%)non-Caucasian,79(78.22%)male and 22(21.78%)female.Surgeons with DO degrees comprised only 3.96%(4)of the cohort,while the vast majority held MDs[96.04%(97)].Mean H-index was 10.55,with male surgeons having a significantly higher score(P=0.002).Most orthopedic surgeons(88.12%,)practiced in academic centers.Of those professionals who occupied leadership positions,14%were women,while 86%were men.Additionally,19(37.25%)United States regions and the District of Columbia lacked an LLRS-member orthopedic surgeon.Total per capita rate across the United States was 0.30 LLRS orthopedic surgeons per 1 million people.CONCLUSION Over 21%of LLRS members are women,surpassing prior benchmarks noted in orthopedic faculty reporting.LLRS members’high research productivity scores imply field dedication that can refine expertise in the limb lengthening and reconstruction space.Gender disparities in leadership remain,however,necessitating greater equity efforts.A low rate of LLRS representation per capita must be addressed geographically as well,to affect improvements in regional care access.This study can serve to support aspiring orthopedic professionals,inform diversity,leadership,and field advancement strategies,and maintain the continued goal of enhanced patient care worldwide. 展开更多
关键词 Limb lengthening and reconstruction Orthopedic surgeon demographics Orthopedic surgeon societal membership Orthopedic fellowships
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Numerical Study of the Biomechanical Behavior of a 3D Printed Polymer Esophageal Stent in the Esophagus by BP Neural Network Algorithm
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作者 Guilin Wu Shenghua Huang +7 位作者 Tingting Liu Zhuoni Yang Yuesong Wu Guihong Wei Peng Yu Qilin Zhang Jun Feng Bo Zeng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2709-2725,共17页
Esophageal disease is a common disorder of the digestive system that can severely affect the quality of life andprognosis of patients. Esophageal stenting is an effective treatment that has been widely used in clinica... Esophageal disease is a common disorder of the digestive system that can severely affect the quality of life andprognosis of patients. Esophageal stenting is an effective treatment that has been widely used in clinical practice.However, esophageal stents of different types and parameters have varying adaptability and effectiveness forpatients, and they need to be individually selected according to the patient’s specific situation. The purposeof this study was to provide a reference for clinical doctors to choose suitable esophageal stents. We used 3Dprinting technology to fabricate esophageal stents with different ratios of thermoplastic polyurethane (TPU)/(Poly-ε-caprolactone) PCL polymer, and established an artificial neural network model that could predict the radial forceof esophageal stents based on the content of TPU, PCL and print parameter. We selected three optimal ratios formechanical performance tests and evaluated the biomechanical effects of different ratios of stents on esophagealimplantation, swallowing, and stent migration processes through finite element numerical simulation and in vitrosimulation tests. The results showed that different ratios of polymer stents had different mechanical properties,affecting the effectiveness of stent expansion treatment and the possibility of postoperative complications of stentimplantation. 展开更多
关键词 Finite element method 3D printing polymer esophageal stent artificial neural network
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Overall Assessment of Heat Transfer for a Rarefied Flow in a Microchannel with Obstacles Using Lattice Boltzmann Method
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作者 Siham Hammid Khatir Naima +7 位作者 Omolayo M.Ikumapayi Cheikh Kezrane Abdelkrim Liazid Jihad Asad Mokdad Hayawi Rahman Farhan Lafta Rashid Naseer Ali Hussien Younes Menni 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期273-299,共27页
The objective of this investigation is to assess the effect of obstacles on numerical heat transfer and fluid flow momentum in a rectangular microchannel(MC).Two distinct configurations were studied:one without obstac... The objective of this investigation is to assess the effect of obstacles on numerical heat transfer and fluid flow momentum in a rectangular microchannel(MC).Two distinct configurations were studied:one without obstacles and the other with alternating obstacles placed on the upper and lower walls.The research utilized the thermal lattice Boltzmann method(LBM),which solves the energy and momentum equations of fluids with the BGK approximation,implemented in a Python coding environment.Temperature jump and slip velocity conditions were utilized in the simulation for the MC and extended to all obstacle boundaries.The study aims to analyze the rarefaction effect,with Knudsen numbers(Kn)of 0.012,0.02,and 0.05.The outcomes indicate that rarefaction has a significant impact on the velocity and temperature distribution.The presence of nine obstacles led to slower fluid movement inside the microchannel MC,resulting in faster cooling at the outlet.In MCs with obstacles,the rarefaction effect plays a crucial role in decreasing the Nusselt number(Nu)and skin friction coefficient(Cf).Furthermore,the study demonstrated that the obstacles played a crucial role in boosting fluid flow and heat transfer in the MC.The findings suggest that the examined configurations could have potential applications as cooling technologies in micro-electro-mechanical systems and microdevice applications. 展开更多
关键词 MICROFLUID rarefied flow LBM MICROCHANNEL Knudsen number numerical simulation
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An Investigation into Forced Convection of a Nanofluid Flowing in a Rectangular Microchannel under the Influence of a Magnetic Field
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作者 Muataz S.Alhassan Ameer A.Alameri +4 位作者 Andrés Alexis Ramírez-Coronel I.B.Sapaev Azher M.Abed David-Juan Ramos-Huallpartupa Rahman S.Zabibah 《Fluid Dynamics & Materials Processing》 EI 2024年第2期311-323,共13页
In line with recent studies,where it has been shown that nanofluids containing graphene have a stronger capacity to boost the heat transfer coefficient with respect to ordinary nanofluids,experiments have been conducted ... In line with recent studies,where it has been shown that nanofluids containing graphene have a stronger capacity to boost the heat transfer coefficient with respect to ordinary nanofluids,experiments have been conducted using water with cobalt ferrite/graphene nanoparticles.In particular,a circular channel made of copper subjected to a constant heatflux has been considered.As nanoparticles are sensitive to the presence of a magneticfield,different conditions have been examined,allowing both the strength and the frequency of such afield to span relatively wide ranges and assuming different concentrations of nanoparticles.According to thefindings,the addition of nanoparticles to thefluid causes its rotation speed to increase by a factor of two,whereas ultraviolet radiation plays a negligible role.The amount of time required to attain the maximum rotation speed of the nanofluid and the Nusselt number have been measured under both constant and alternating magneticfields for a ferrofluid with a concentration of 0.5%and atflow Reynolds number of 550 and 1750. 展开更多
关键词 Nano fluid rectengular tube magnetic field
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Association of daily sitting time and leisure-time physical activity with body fat among U.S.adults
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作者 Jingwen Liao Min Hu +4 位作者 Kellie Imm Clifton J.Holmes Jie Zhu Chao Cao Lin Yang 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期195-203,共9页
Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investi... Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investigated the independent and joint associations of daily sitting time and physical activity with body fat among adults.Methods:This was a cross-sectional analysis of U.S.nationally representative data from the National Health and Nutrition Examination Survey2011-2018 among adults aged 20 years or older.Daily sitting time and leisure-time physical activity(LTPA)were self-reported using the Global Physical Activity Questionnaire.Body fat(total and trunk fat percentage)was determined via dual X-ray absorptiometry.Results:Among 10,808 adults,about 54.6%spent 6 h/day or more sitting;more than one-half reported no LTPA(inactive)or less than 150 min/week LTPA(insufficiently active)with only 43.3%reported 150 min/week or more LTPA(active)in the past week.After fully adjusting for sociodemographic data,lifestyle behaviors,and chronic conditions,prolonged sitting time and low levels of LTPA were associated with higher total and trunk fat percentages in both sexes.When stratifying by LTPA,the association between daily sitting time and body fat appeared to be stronger in those who were inactive/insuufficiently active.In the joint analyses,inactive/insuufficiently active adults who reported sitting more than 8 h/day had the highest total(female:3.99%(95%confidence interval(95%CI):3.09%-4.88%);male:3.79%(95%CI:2.75%-4.82%))and trunk body fat percentages(female:4.21%(95%CI:3.09%-5.32%);male:4.07%(95%CI:2.95%-5.19%))when compared with those who were active and sitting less than 4 h/day.Conclusion:Prolonged daily sitting time was associated with increased body fat among U.S.adults.The higher body fat associated with 6 h/day sitting may not be offset by achieving recommended levels of physical activity. 展开更多
关键词 ADULTS Body fat distribution Physical activity Sitting time
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Comprehensive analysis of the role of ubiquitin-specific peptidases in colorectal cancer:A systematic review
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作者 Eman Al-Balushi Amina Al Marzouqi +10 位作者 Shima Tavoosi Amir Hossein Baghsheikhi Arash Sadri Leyla Sharifi Aliabadi Mohammad-Mahdi Salarabedi Syed Azizur Rahman Nabeel Al-Yateem Alireza Mosavi Jarrahi Aram Halimi Mohammad Ahmadvand Wael M Abdel-Rahman 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第1期197-213,共17页
BACKGROUND Colorectal cancer(CRC)is the third most frequent and the second most fatal cancer.The search for more effective drugs to treat this disease is ongoing.A better understanding of the mechanisms of CRC develop... BACKGROUND Colorectal cancer(CRC)is the third most frequent and the second most fatal cancer.The search for more effective drugs to treat this disease is ongoing.A better understanding of the mechanisms of CRC development and progression may reveal new therapeutic strategies.Ubiquitin-specific peptidases(USPs),the largest group of the deubiquitinase protein family,have long been implicated in various cancers.There have been numerous studies on the role of USPs in CRC;however,a comprehensive view of this role is lacking.AIM To provide a systematic review of the studies investigating the roles and functions of USPs in CRC.METHODS We systematically queried the MEDLINE(via PubMed),Scopus,and Web of Science databases.RESULTS Our study highlights the pivotal role of various USPs in several processes implicated in CRC:Regulation of the cell cycle,apoptosis,cancer stemness,epithelial–mesenchymal transition,metastasis,DNA repair,and drug resistance.The findings of this study suggest that USPs have great potential as drug targets and noninvasive biomarkers in CRC.The dysregulation of USPs in CRC contributes to drug resistance through multiple mechanisms.CONCLUSION Targeting specific USPs involved in drug resistance pathways could provide a novel therapeutic strategy for overcoming resistance to current treatment regimens in CRC. 展开更多
关键词 Ubiquitin-specific peptidases Colorectal cancer Deubiquitinase protein family Drug target discovery Biomarker discovery
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Predicting bioactive compounds and cancer-related molecular targets of lotus seedpod (Receptaculum Nelumbinis) based on network pharmacology and molecular docking
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作者 Jian-Lin Shen Meng-Tong Zhang +8 位作者 Fei Li Jia-Yu Huang Quan-Sheng Xu Han-Yue Zhang Jun Zhang Jing Li Yan-Ping Li Qi Zou Xiao-Yin Wang 《Food and Health》 2024年第2期14-41,共28页
Background:Lotus seedpod(Receptaculum Nelumbinis)is the abundant by-products produced during lotus seed processing,and the sources are usually considered to be wastes and are abandoned outdoors or incinerated.This stu... Background:Lotus seedpod(Receptaculum Nelumbinis)is the abundant by-products produced during lotus seed processing,and the sources are usually considered to be wastes and are abandoned outdoors or incinerated.This study aims at predicting its bioactive compounds and cancer-related molecular targets against six cancers,including lung cancer,gastric cancer,liver cancer,breast cancer,ovarian cancer and cervical cancer.Methods:Network pharmacology and molecular docking methods were performed.Results:Network pharmacology results indicated that 14 core compounds(liensinine,tetrandrine,lysicamine,tricin,sanleng acid,cireneol G,ricinoleic acid,linolenic acid,5,7-dihydroxycoumarin,apigenin,luteolin,morin,quercetin and isorhamnetin)and 10 core targets(AKT1,ESR1,HSP90AA1,JUN,MAPK1,MAPK3,PIK3CA,PIK3R1,SRC and STAT3)were screened for lotus seedpod against the six cancers.Molecular docking analysis suggested that the binding abilities between the core compounds and the core targets were mostly strong.GO analysis revealed that the intersected targets between the bioactive compounds of lotus seedpod and the six cancers were significantly related to biological processes,cell compositions and molecular functions.KEGG analysis showed that PI3K-Akt,TNF,Ras,MAPK,HIF-1 and C-type lectin receptor signaling pathways were notably involved in the anti-cancer activities of lotus seedpod against the six cancers.Conclusions:14 core compounds and 10 core targets were screened for lotus seedpod against lung cancer,gastric cancer,liver cancer,breast cancer,ovarian cancer and cervical cancer.This study supports the application of lotus seedpod in treating cancers,and promotes the recycling and the high-value utilization. 展开更多
关键词 Lotus seedpod ANTI-CANCER Bioactive compounds Molecular targets Network pharmacology Molecular docking.
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Design and research on a variable ballast system for deep-sea manned submersibles 被引量:6
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作者 邱中梁 《Journal of Marine Science and Application》 2008年第4期255-260,共6页
Variable ballast systems are necessary for manned submersibles to adjust their buoyancy.In this paper,the design of a variable ballast system for a manned submersible is described.The variable ballast system uses a su... Variable ballast systems are necessary for manned submersibles to adjust their buoyancy.In this paper,the design of a variable ballast system for a manned submersible is described.The variable ballast system uses a super high pressure hydraulic seawater system.A super high pressure seawater pump and a deep-sea brushless DC motor are used to pump seawater into or from the variable ballast tank,increasing or decreasing the weight of the manned submersible.A magnetostrictive linear displacement transducer can detect the seawater level in the variable ballast tank.Some seawater valves are used to control pumping direction and control on-off states.The design and testing procedure for the valves is described.Finally,the future development of variable ballast systems and seawater hydraulic systems is projected. 展开更多
关键词 深海 潜水器 变量镇流系统 海水排水泵
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Improved Whale Optimization with Local-Search Method for Feature Selection 被引量:1
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作者 Malek Alzaqebah Mutasem KAlsmadi +12 位作者 Sana Jawarneh Jehad Saad Alqurni Mohammed Tayfour Ibrahim Almarashdeh Rami Mustafa A.Mohammad Fahad A.Alghamdi Nahier Aldhafferi Abdullah Alqahtani Khalid A.Alissa Bashar A.Aldeeb Usama A.Badawi Maram Alwohaibi Hayat Alfagham 《Computers, Materials & Continua》 SCIE EI 2023年第4期1371-1389,共19页
Various feature selection algorithms are usually employed to improve classification models’overall performance.Optimization algorithms typically accompany such algorithms to select the optimal set of features.Among t... Various feature selection algorithms are usually employed to improve classification models’overall performance.Optimization algorithms typically accompany such algorithms to select the optimal set of features.Among the most currently attractive trends within optimization algorithms are hybrid metaheuristics.The present paper presents two Stages of Local Search models for feature selection based on WOA(Whale Optimization Algorithm)and Great Deluge(GD).GD Algorithm is integrated with the WOA algorithm to improve exploitation by identifying the most promising regions during the search.Another version is employed using the best solution found by the WOA algorithm and exploited by the GD algorithm.In addition,disruptive selection(DS)is employed to select the solutions from the population for local search.DS is chosen to maintain the diversity of the population via enhancing low and high-quality solutions.Fifteen(15)standard benchmark datasets provided by the University of California Irvine(UCI)repository were used in evaluating the proposed approaches’performance.Next,a comparison was made with four population-based algorithms as wrapper feature selection methods from the literature.The proposed techniques have proved their efficiency in enhancing classification accuracy compared to other wrapper methods.Hence,the WOA can search effectively in the feature space and choose the most relevant attributes for classification tasks. 展开更多
关键词 OPTIMIZATION whale optimization algorithm great deluge algorithm feature selection and classification
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Phyllosphere eukaryotic microalgal communities in rainforests:Drivers and diversity
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作者 Ben-Wen Liu Shu-Yin Li +1 位作者 Huan Zhu Guo-Xiang Liu 《Plant Diversity》 SCIE CAS CSCD 2023年第1期45-53,共9页
Phyllosphere algae are common in tropical rainforests,forming visible biofilms or spots on plant leaf surfaces.However,knowledge of phyllosphere algal diversity and the environmental factors that drive that diversity ... Phyllosphere algae are common in tropical rainforests,forming visible biofilms or spots on plant leaf surfaces.However,knowledge of phyllosphere algal diversity and the environmental factors that drive that diversity is limited.The aim of this study is to identify the environmental factors that drive phyllosphere algal community composition and diversity in rainforests.For this purpose,we used single molecule real-time sequencing of full-length 18S rDNA to characterize the composition of phyllosphere microalgal communities growing on four host tree species(Ficus tikoua,Caryota mitis,Arenga pinnata,and Musa acuminata) common to three types of forest over four months at the Xishuangbanna Tropical Botanical Garden,Yunnan Province,China.Environmental 18S rDNA sequences revealed that the green algae orders Watanabeales and Trentepohliales were dominant in almost all algal communities and that phyllosphere algal species richness and biomass were lower in planted forest than in primeval and reserve rainforest.In addition,algal community composition differed significantly between planted forest and primeval rainforest.We also found that algal communities were affected by soluble reactive phosphorous,total nitrogen,and ammonium contents.Our findings indicate that algal community structure is significantly related to forest type and host tree species.Furthermore,this study is the first to identify environmental factors that affect phyllosphere algal communities,significantly contributing to future taxonomic research,especially for the green algae orders Watanabeales and Trentepohliales.This research also serves as an important reference for molecular diversity analysis of algae in other specific habitats,such as epiphytic algae and soil algae. 展开更多
关键词 Full-length 18S rDNA sequences Cryptic diversity Environmental factors High-throughput sequence Phyllosphere algae Tropical rainforest
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Lake regime shift from submerged macrophyte to phytoplankton affected phosphorus speciation in sediment and eutrophic state in Caohai Lake,Guizhou,China
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作者 Jixing DONG Yanmin GUO +5 位作者 Pinhua XIA Yuanbin TIAN Feifei ZHENG Anyan LI Tao LIN Ruiwen LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第6期2262-2275,共14页
To understand the effect of regime shift in Caohai Lake in Yunnan-Guizhou Plateau,SW China from submerged macrophyte dominance to phytoplankton dominance on the specification and distribution of phosphorus and on ecol... To understand the effect of regime shift in Caohai Lake in Yunnan-Guizhou Plateau,SW China from submerged macrophyte dominance to phytoplankton dominance on the specification and distribution of phosphorus and on ecological and environmental states,changes in phosphorus specification in the sediments and water were studied.The form,composition,and distribution of phosphorus in sediment were sampled in July 2020(before regime shift)and July 2021(after regime shift)were analyzed.Results reveal that phosphorus content in sediment was lower than that those of Erhai Lake and Dianchi Lake,Yunnan,SW China,on the same plateau,and was lower than those of Taihu Lake,Chaohu Lake,and Poyang Lake in the middle-lower Changjiang(Yangtze)River Plain.Organic phosphorus(Or-P)was the main form(up to 60%),followed by inactive phosphorus(Ina-P),and the active phosphorus(Act-P),the least,which is opposite to those of Taihu Lake and Poyang Lake in the middle-lower Changjiang River Plain in the eastern China.Or-P content was high,indicating a high potential risk of phosphorous release.After the regime shift,the total phosphorus in sediment decreased from 0.87±0.13 to 0.70±0.13 g/kg.The proportion of Or-P and Act-P decreased from 68.23% to 65.32% and from 5.35% to 4.69%,respectively.In contrast,the proportion of Ina-P increased from 26.42% to 29.99%.The Moran’s I index revealed that the heterogeneity of the spatial distributions of the total phosphorus(S-TP)and Act-P in the sediments before regime shift was significant(P<0.1).However,the heterogeneity of the spatial distributions of S-TP and the various forms of phosphorus after regime shift was not significant(P>0.05).The regime shift aggravated the eutrophication of the lake,the trophic level index(TLI)increased from 48.42 to 54.49(P<0.01),and the previously mesotrophic lake became a mildly eutrophic lake.The results of this study revealed the impact of regime shift in the lake from submerged macrophyte dominance to phytoplankton dominance on the composition and spatial distribution of phosphorus in sediments and provided a basis for the restoration of eutrophicated and aquatic ecosystem degraded lakes. 展开更多
关键词 Caohai Lake SEDIMENT phosphorus specification regime shift
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5-mRNA-based prognostic signature of survival in lung adenocarcinoma
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作者 Qian-Lin Xia Xiao-Meng He +3 位作者 Yan Ma Qiu-Yue Li Yu-Zhen Du Jin Wang 《World Journal of Clinical Oncology》 CAS 2023年第1期27-39,共13页
BACKGROUND Lung adenocarcinoma(LUAD)is the most common non-small-cell lung cancer,with a high incidence and a poor prognosis.AIM To construct effective predictive models to evaluate the prognosis of LUAD patients.METH... BACKGROUND Lung adenocarcinoma(LUAD)is the most common non-small-cell lung cancer,with a high incidence and a poor prognosis.AIM To construct effective predictive models to evaluate the prognosis of LUAD patients.METHODS In this study,we thoroughly mined LUAD genomic data from the Gene Expression Omnibus(GEO)(GSE43458,GSE32863,and GSE27262)and the Cancer Genome Atlas(TCGA)datasets,including 698 LUAD and 172 healthy(or adjacent normal)lung tissue samples.Univariate regression and LASSO regression analyses were used to screen differentially expressed genes(DEGs)related to patient prognosis,and multivariate Cox regression analysis was applied to establish the risk score equation and construct the survival prognosis model.Receiver operating characteristic curve and Kaplan-Meier survival analyses with clinically independent prognostic parameters were performed to verify the predictive power of the model and further establish a prognostic nomogram.RESULTS A total of 380 DEGs were identified in LUAD tissues through GEO and TCGA datasets,and 5 DEGs(TCN1,CENPF,MAOB,CRTAC1 and PLEK2)were screened out by multivariate Cox regression analysis,indicating that the prognostic risk model could be used as an independent prognostic factor(Hazard ratio=1.520,P<0.001).Internal and external validation of the model confirmed that the prediction model had good sensitivity and specificity(Area under the curve=0.754,0.737).Combining genetic models and clinical prognostic factors,nomograms can also predict overall survival more effectively.CONCLUSION A 5-mRNA-based model was constructed to predict the prognosis of lung adenocarcinoma,which may provide clinicians with reliable prognostic assessment tools and help clinical treatment decisions. 展开更多
关键词 Lung adenocarcinoma Differentially expressed genes Prognostic signature Risk score NOMOGRAM
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The impacts of ambiguity in preparation of 80% sulfuric acid solution and shaking time control of calibration solution on the determination of transparent exopolymer particles
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作者 Congcong Guo Guicheng Zhang +2 位作者 Shan Jian Wei Ma Jun Sun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第4期50-58,共9页
The quantification of transparent exopolymer particles(TEP) by colorimetric method is of large error and low repeatability,one major reason of which is related to the absence of clear definition and evaluation for par... The quantification of transparent exopolymer particles(TEP) by colorimetric method is of large error and low repeatability,one major reason of which is related to the absence of clear definition and evaluation for part steps of the original method.It is obscure that the 80% sulfuric acid solution,acted as the extraction solution in the determination of TEP,is prepared based on a volume ratio or mass ratio.Furthermore,the change of solubility of recently available Gum Xanthan(GX) from the market means that the original protocol is no longer applicable,and the grinding of GX stock solution with a tissue grinder is replaced by shaking with a rotating shaker in the study to prevent the excessive dissolution of GX.We found that different preparation techniques could result in the varied concentrations of 80% H_(2)SO_(4).The duration of shaking during the preparation of standard solution significantly affected the slope of the calibration curve,which caused different correction results of TEP.The impacts of different extraction solution concentrations and shaking time of GX solution on the quantification of TEP were investigated based on the field sampling and laboratory analysis.The extraction capacities of H_(2)SO_(4) with different concentrations for Alcian Blue were distinct,but had limited effect on the final measuring result of TEP.The change of the standard curve slope came along with the variation of shaking time,which markedly altered the detection limit and calibration result,and the extended shaking time was in favor of the determination of low-concentration TEP.It was suggested that the extraction solution concentration,shaking time and filtration volume of standard solution are required to be well controlled and selected to obtain more accurate results for TEP with different concentrations. 展开更多
关键词 transparent exopolymer particles determination method method improvement sulfuric acid shaking time
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