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world Journal of Mechanics 2024年第5期14卷 73-96页

作者： David w. A. Rees Abdelraouf M. Sami Alsheikh College of Engineering and Design Brunel University Uxbridge UK

Three aluminium channel sections of US standard extruded dimension are mounted as cantilevers with x-axis symmetry. The flexural bending and shear that arise with applied axial torsion are each considered theoretically and numerically in terms of two longitudinal axes of loading not coincident with the shear centre. In particular, the warping displacements, stiffness and stress distributions are calculated for torsion applied to longitudinal axes passing through the section’s centroid and its web centre. The stress conversions derived from each action are superimposed to reveal a net sectional stress distribution. Therein, the influence of the axis position upon the net axial and shear stress distributions is established compared to previous results for each beam when loading is referred to a flexural axis through the shear centre. within the net stress analysis is, it is shown how the constraint to free warping presented by the end fixing modifies the axial stress. The latter can be identified with the action of a ‘bimoment’ upon each thin-walled section.

关键词： Thin-Aluminium Channels Cantilever Beam Bending Shear Torsion warping Bimoment Flexural Axis Centre of Twist Centroid Shear Centre Torsional Stiffness Constrained Stress

Soybean Response to weed Residues in the Soil

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Agricultural Sciences 2024年第8期15卷 801-811页

作者： Dwayne D. Joseph Michael w. Marshall Matthew Cutulle Department of Plant and Environmental Sciences Clemson University Clemson SC USA Edisto Research and Education Center Clemson University Blackville SC USA Coastal Research and Education Center Clemson University Charleson SC USA

Soybean production systems that return plant residues to the soil surface are gaining in popularity. As these practices become more widespread, more crop and weed residues are being introduced into the upper soil profile. Greenhouse studies were conducted to determine the effects of varying concentrations of Palmer amaranth and pitted morningglory plant residues (aboveground portion of the plant) on soybean production. The study was arranged in a completely randomized experimental design with five treatments and five replications. Palmer amaranth and pitted morningglory residues were incorporated into soil at 20,000, 40,000, 80,000 and 160,000 ppm. Inert plastic residue at the same residue levels was included as a check. Soybean dry weight, leaf area and leaf tissue nutrient content were recorded during the study. A decrease in soybean dry weight and leaf area was observed as Palmer amaranth residue in the soil increased. Palmer amaranth residues of 160,000 ppm and 80,000 ppm in the soil significantly reduced soybean dry weight by 69% and 59%, respectively, and soybean leaf area by 60% and 57%, respectively. In contrast, pitted morningglory and inert plastic residues had no observable effect on soybean growth and development. This study demonstrated Palmer amaranth residues in the soil impacted early season soybean growth and development.

关键词： Reduced Tillage Plant Residues Allelopathy Glycine max L.

Theory of Flexural Shear, Bending and Torsion for a Thin-walled Beam of Open Section

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world Journal of Mechanics 2024年第3期14卷 23-53页

作者： David w. A. Rees Abdelraouf M. Sami Alsheikh College of Engineering and Design Brunel University Uxbridge UK

Aspects of the general Vlasov theory are examined separately as applied to a thin-walled channel section cantilever beam under free-end end loading. In particular, the flexural bending and shear that arise under transverse shear and axial torsional loading are each considered theoretically. These analyses involve the location of the shear centre at which transverse shear forces when applied do not produce torsion. This centre, when taken to be coincident with the centre of twist implies an equivalent reciprocal behaviour. That is, an axial torsion applied concentric with the shear centre will twist but not bend the beam. The respective bending and shear stress conversions are derived for each action applied to three aluminium alloy extruded channel sections mounted as cantilevers with a horizontal principal axis of symmetry. Bending and shear are considered more generally for other thin-walled sections when the transverse loading axes at the shear centre are not parallel to the section = s centroidal axes of principal second moments of area. The fixing at one end of the cantilever modifies the St Venant free angular twist and the free warping displacement. It is shown from the wagner-Kappus torsion theory how the end constrained warping generates an axial stress distribution that varies with the length and across the cross-section for an axial torsion applied to the shear centre. It should be mentioned here for wider applications and validation of the Vlasov theory that attendant papers are to consider in detail bending and torsional loadings applied to other axes through each of the centroid and the web centre. Therein, both bending and twisting arise from transverse shear and axial torsion applied to each position being displaced from the shear centre. Here, the influence of the axis position upon the net axial and shear stress distributions is to be established. That is, the net axial stress from axial torsional loading is identified with the sum of axial stress

关键词： Thin wall Theory Cantilever Beam Open Channel Section Principal Axes Flexure Transverse Shear Torsion Shear Centre Shear Flow warping Fixed-End Constraint

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《音乐社会学导论》选译

新美术 2024年第3期45卷 25-63页

作者： [德]特奥多尔·w.阿多诺罗逍然(译) 不详中国美术学院

《作为社会棱镜的音乐》一文已经提到,阿多诺在思想与论述中都是有意识地拒绝体系化表达的。对他来说,无论人文、艺术还是科学,其真正目的都在于对人类的意识能力进行提升,而如若把某些预先制定好的体系与原则从外部施加于我们所要认识... 详细信息

《作为社会棱镜的音乐》一文已经提到,阿多诺在思想与论述中都是有意识地拒绝体系化表达的。对他来说,无论人文、艺术还是科学,其真正目的都在于对人类的意识能力进行提升,而如若把某些预先制定好的体系与原则从外部施加于我们所要认识的事物上,则无异于是在抹除事物自身的独特属性以及事物之间的微妙差异,那么也就是在伤害人类的意识能力。所以,阿多诺要求音乐不能仅仅是被动地接受并施用素材(其中包括体系、手法、风格等)。

关键词：音乐社会学阿多诺事物自身体系化导论独特属性意识

Circulating tumor cells shielded with extracellular vesicle-derived CD45 evade T cell attack to enable metastasis

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Signal Transduction and Targeted Therapy 2024年第5期9卷 2114-2131页

作者： Chuan Yang Xueping wang Kenneth K.w.To Caimei Cui Min Luo Shaocong wu Lamei Huang Kai Fu Can Pan Zeyu Liu Teng Fan Caibo Yang Fang wang Liwu Fu State Key Laboratory of Oncology in South China Guangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060P.R.China School of Pharmacy Faculty of MedicineThe Chinese University of Hong KongHong KongChina LABVIV Technology(Shenzhen)Co. LtdShenzhen 518057China

Circulating tumor cells(CTCs)are precursors of distant metastasis in a subset of cancer patients.A better understanding of CTCs heterogeneity and how these CTCs survive during hematogenous dissemination could lay the foundation for therapeutic prevention of cancer *** remains elusive how CTCs evade immune surveillance and elimination by immune *** this study,we unequivocally identified a subpopulation of CTCs shielded with extracellular vesicle(EVs)-derived CD45(termed as CD45^(+)CTCs)that resisted T cell attack.A higher percentage of CD45^(+)CTCs was found to be closely correlated with higher incidence of metastasis and worse prognosis in cancer ***,CD45^(+)tumor cells orchestrated an immunosuppressive milieu and CD45^(+)CTCs exhibited remarkably stronger metastatic potential than CD45−CTCs in ***,CD45 expressing on tumor surfaces was shown to form intercellular CD45-CD45 homophilic interactions with CD45 on T cells,thereby preventing CD45 exclusion from TCR-pMHC synapse and leading to diminished TCR signaling transduction and suppressed immune ***,these results pointed to an underappreciated capability of EVs-derived CD45-dressed CTCs in immune evasion and metastasis,providing a rationale for targeting EVs-derived CD45 internalization by CTCs to prevent cancer metastasis.

关键词： CD45 metastasis prevention

Combined Effect of Outdoor Time and Other Modifiable Factors on Myopia Incidence Among Children and Adolescents—9 PLADs,China,2020

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China CDC weekly 2024年第9期6卷 151-156,I0001,I0002页

作者： Panliang Zhong Yunfei Liu Ning Ma Jiajia Dang Di Shi Shan Cai Ziyue Chen Yanhui Dong Peijin Hu Jun Ma Patrick w.C Lau Randall S.Stafford Yi Song Institute of Child and Adolescent Health School of Public HealthPeking UniversityNational Health Commission Key Laboratory of Reproductive HealthBeijingChina Department of Sport Physical Education&HealthHong Kong Baptist UniversityKowloon TongHong Kong Special Administrative RegionChina Department of Medicine Stanford Prevention Research CenterStanford University School of MedicineStanfordCAUnited States

Summary what is already known about this topic?Myopia has been identified as a significant emerging challenge and policy priority among children and adolescents in China by the Ministry of Education and seven other *** research has been conducted to investigate the collective impact of outdoor time and other modifiable factors on the incidence of myopia.

关键词： Incidence collective policy

Multi-resistant bacteria in spontaneous bacterial peritonitis: A new step in management?

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world Journal of Gastroenterology 2014年第39期20卷 14079-14086页

作者： Angelo Alves de Mattos ane Micheli Costabeber Livia Caprara Lion?o Cristiane Valle Tovo Department of Gastroenterology Universidade Federal de Ciências da Saúde de Porto Alegre Porto Alegre 90430-080 Brasil

Spontaneous bacterial peritonitis(SBP) is the most typical infection observed in cirrhosis patients. SBP is responsible for an in-hospital mortality rate of approximately 32%. Recently, pattern changes in the bacterial flora of cirrhosis patients have been observed, and an increase in the prevalence of infections caused by multi-resistant bacteria has been noted. The wide-scale use of quinolones in the prophylaxis of SBP has promoted flora modifications and resulted in the development of bacterial resistance. The efficacy of traditionally recommended therapy has been low in nosocomial infections(up to 40%), and multi-resistance has been observed in up to 22% of isolated germs in nosocomial SBP. For this reason, the use of a broad empirical spectrum antibiotic has been suggested in these situations. The distinction between community-acquired infectious episodes, healthcare-associated infections, or nosocomial infections, and the identification of risk factors for multi-resistant germs can aid in the decision-making process regarding the empirical choice of antibiotic therapy. Broad-spectrum antimicrobial agents, such as carbapenems with or without glycopeptides or piperacillin-tazobactam, should be considered for the initial treatment not only of nosocomial infections but also of healthcare-associated infections when the risk factors or severity signs for multi-resistant bacteria are apparent. The use of cephalosporins should be restricted to community-acquired infections.

关键词： Spontaneous peritonitis Multi-resistant bacteria Cirrhosis Infection Ascites

Selective conversion of N_(2) to NH_(3) on highly dispersed RuO_(2) using amphiphilic ionic liquid-anchored fibrous carbon structure

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Journal of Energy Chemistry 2022年第4期31卷 474-482页

作者： Kahyun ham Muhammad Salman Sunki Chung Minjun Choi HyungKuk Ju Hye Jin Lee Jaeyoung Lee School of Earth Sciences and Environmental Engineering Gwangju Institute of Science and Technology(GIST)123 Cheomdangwagi-RoGwangju 61005South Korea International Future Research Center of Chemical Energy Storage and Conversion Processes GIST123 Cheomdangwagi-RoGwangju 61005South Korea Ertl Center for Electrochemical and Catalysis GIST123 Cheomdangwagi-RoGwangju 61005South Korea Department of Chemistry and Green-Nano Materials Research Center Kyungpook National University80 Daehak-RoDaegu-city 41566South Korea Hydrogen Research Department Korea Institute of Energy Research152 Gajeong-RoYuseong-guDaejeon 34129South Korea

Ammonia (NH_(3)) plays a key role in the agricultural fertilizer and commodity chemical industries and is useful for exploring hydrogen storage *** electrochemical nitrogen reduction reaction (NRR) is receiving attention as an environmentally sustainable NH_(3) synthesis replacement for the traditional Haber–Bosch process owing to its near ambient reaction conditions (wever,its NH_(3) yield and faradaic efficiency are extremely low because of the sluggish kinetics of N≡N bond dissociation and the hindrance from competitive hydrogen *** overcome these challenges,we herein introduce a dual-functionalized ionic liquid (1-(4-hydroxybutyl)-3-methylimidazolium hydroxide[HOBIM]OH) for a highly dispersed ruthenium oxide electrocatalyst to achieve a biased *** observed uniform distribution of RuO_(2) on the carbon fiber and increase in the surface area for N_(2) adsorption by limiting proton access can be attributed to the presence of imidazolium ***,extensive N_(2) adsorption contributes to enhanced NRR selectivity with an NH_(3) yield of 3.0×10^(-10)mol cm^(-2)s^(-1)(91.8μg h^(-1)mg^(-1)) and a faradaic efficiency of 2.2%at-0.20 V_(RHE).we expect our observations to provide new insights into the design of effective electrode structures for electrochemical NH;synthesis.

关键词： Ammonia synthesis Nitrogen reduction reaction Imidazolium-based ionic liquid Ruthenium oxide

The risk of prostate cancer on incidental finding of an avid prostate uptake on 2-deoxy-2-[^(18)F]fluoro-D-glucose positron emission tomography/computed tomography for non-prostate cancer-related pathology:A single centre retrospective study

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Asian Journal of Urology 2024年第1期11卷 33-41页

作者： Anthony Franklin Troy Gianduzzo Boon Kua David wong Louise McEwan James walters Rachel Esler Matthew J.Roberts Geoff Coughlina John w.Yaxley Department of Urology The Wesley HospitalBrisbaneQLDAustralia wesley Medical Research BrisbaneQLDAustralia School of Medicine The University of QueenslandBrisbaneQLDAustralia Department of Radiology Wesley Medical ImagingBrisbaneQLDAustralia Department of Urology Royal Brisbane and Women's HospitalBrisbaneQLDAustralia

Objective:To review the risk of prostate cancer(PCa)in men with incidentally reported increased intraprostatic uptake at 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography/computed tomography(18F-FDG PET/CT)ordered at Department of Urology,The wesley Hospital,Brisbane,QLD,Australia for non-PCa related ***:Retrospective analysis of consecutive men between August 2014 and August 2019 presenting to a single institution for 18F-FDG PET/CT for non-prostate related conditions was *** were classified as benign,indeterminate,or malignant depending of the results of prostate-specific antigen(PSA),PSA velocity,biopsy histopathology,and three-Tesla(3 T)multiparametric MRI(mpMRI)Prostate Imaging Reporting and Data System score,or gallium-68-prostate-specific membrane antigen(68Ga-PSMA)PET/CT ***:Three percent(273/9122)of men demonstrated 18F-FDG avidity within the ***-five percent(231/273)were further investigated,including with PSA tests(227/231,98.3%),3 T mpMRI(68/231,29.4%),68Ga-PSMA PET/CT(33/231,14.3%),and prostate biopsy(57/231,24.7%).Results were considered benign in 130/231(56.3%),indeterminate in 31/231(13.4%),and malignant in 70/231(30.3%).PCa was identified in 51/57(89.5%)of the men who proceeded to biopsy,including 26/27(96.3%)men with Prostate Imaging Reporting and Data System scores 4-5 mpMRI and six men with a positive 68Ga-PSMA PET/*** most common Gleason score on biopsy was greater than or equal to 4+5(14/51,27.5%).68Ga-PSMA PET/CT was concordant with the 18F-FDG findings in 26/33(78.8%).All 13 men with a positive concordant 18F-FDG,3 T mpMRI,and 68Ga-PSMA PET/CT had PCa on *** was no statistically significant difference in the 18F-FDG maximum standardized uptake value between the benign or malignant groups(5.7 vs.6.1;p=0.580).Conclusion:In this study,after an incidental finding of an avid intraprostatic lesion on 18F-FDG PET/CT,70 of the 231 cases(30.3%;0.8%of the entire cohort)had results c

关键词： Prostatecancer Positionemission tomography Multiparametric magneticresonance imaging Prostatebiopsy

A comparison of conventional and computer-assisted semen analysis.（CRISMAS software） using samples from 166 young Danish men

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Asian Journal of Andrology 2011年第3期13卷 453-458,513页

作者： Anne Vested Cecilia H Ramlau-Hansen Jens P Bonde ane M Thulstrup Susanne L Kristensen Gunnar Toft Danish Ramazzini Center Department of Occupational Medicine Aarhus University Hospital DK-8000 Aarhus C Denmark Department of Occupational and Environmental Medicine Copenhagen University Hospital Bispebjerg DK-2400 Copenhagen NV Denmark

The aim of the present study was to compare assessments of sperm concentration and sperm motility analysed by conventional semen analysis with those obtained by computer-assisted semen analysis （CASA）（Copenhagen Rigshospitalet Image House Sperm Motility Analysis System （CRISMAS） 4.6 software） using semen samples from 166 young Danish men. The CRISMAS software identifies sperm concentration and classifies spermatozoa into three motility categories. To enable comparison of the two methods, the four motility stages obtained by conventional semen analysis were, based on their velocity classifications, divided into three stages, comparable to the three CRISMAS motility categories： rapidly progressive （A）, slowly progressive （B） and non-progressive （C＋ D）. Differences between the two methods were large for all investigated parameters （P〈0.001）. CRISMAS overestimated sperm concentration and the proportion of rapidly progressive spermatozoa and, consequently, underestimated the percentages of slowly progressive and non-progressive spermatozoa, compared to the conventional method. To investigate whether results drifted according to time of semen analysis, results were pooled into quarters according to date of semen analysis. CRISMAS motility results appeared more stable over time compared to the conventional analysis; however, neither method showed any trends. Apparently, CRISMAS CASA results and results from the conventional method were not comparable with respect to sperm concentration and motility analysis. This needs to be accounted for in clinics using this software and in studies of determinants of these semen characteristics.

关键词： computer-assisted semen analysis reproduction semen analysis sperm concentration sperm motility