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Visualization of atomic scale reaction dynamics of supported nanocatalysts during oxidation and ammonia synthesis using in-situ environmental(scanning) transmission electron microscopy

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Journal of Energy Chemistry 2021年第6期30卷 281-290,I0007页

作者： Michael R.Ward Robert W.Mitchell edward d.boyes Pratibha L.Gai The York Nanocentre University of YorkYork YO105DDUK department of Physics University of YorkYork YO105DDUK department of Electronic Engineering University of YorkYork YO105DDUK department of Chemistry University of YorkYork YO105DDUK

Reaction dynamics in gases at operating temperatures at the atomic level are the basis of heterogeneous gas-solid catalyst reactions and are crucial to the catalyst *** noble metal nanocatalysts such as platinum are of interest in fuel cells and as diesel oxidation catalysts for pollution control,and practical ruthenium nanocatalysts are explored for ammonia *** and graphitic carbons are of interest as supports for the *** considerable literature on the catalytic processes on graphite and graphitic supports,reaction dynamics of the nanocatalysts on the supports in different reactive gas environments and operating temperatures at the single atom level are not well *** we present real time in-situ observations and analyses of reaction dynamics of Pt in oxidation,and practical Ru nanocatalysts in ammonia synthesis,on graphite and related supports under controlled reaction environments using a novel in-situ environmental(scanning) transmission electron microscope with single atom *** recording snapshots of the reaction dynamics,the behaviour of the catalysts is *** images reveal single metal atoms,clusters of a few atoms on the graphitic supports and the support *** all play key roles in the mobility,sintering and growth of the *** experimental findings provide new structural insights into atomic scale reaction dynamics,morphology and stability of the nanocatalysts.

关键词： In-situ visualization Atomic scale reaction dynamics In-situ environmental scanning transmission electron microscopy with single atom resolution Supported nanoparticles Ammonia synthesis Oxidation reactions

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dEM analysis of the influence of stirrer design on die filling with forced powder feeding

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Particuology 2024年第5期88卷 107-115页

作者： Chao Zheng edward Yost Ariel R.Muliadi Nicolin Govender Ling Zhang Chuan-Yu Wu School of Chemistry and Chemical Engineering University of SurreyGuildfordGU2 7XHUnited Kingdom Small Molecule Pharmaceutics GenentechInc.One DNA WaySouth San FranciscoCA94080USA

die filling is a critical stage during powder compaction,which can significantly affect the product quality and *** this paper,a forced feeder is introduced attempting to improve the filling performance of a lab-scale die filling *** die filling process is analysed with a graphics processing units(GPU)enhanced discrete element method(dEM).Various stirrer designs are assessed for a wide range of process settings(i.e.,stirrer speed,filling speed)to explore their influence on the die filling performance of free-flowing *** results show that die filing with the novel helical-ribbon(i.e.,type d)stirrer design exhibits the highest filling ratio,implying that it is the most robust stirrer design for the feeder configuration ***,die filling performance with the type d stirrer design is a function of the stirrer speed and the filling speed.A positive variation of filling ratio(ηf>0%)can be ensured over the whole range of filling speed by adjusting the stirrer speed(i.e.,increasing the stirrer speed).The approach used in this study can not only help understand how the stirrer design affects the die filling performance but also guide the optimization of feeder system and process settings.

关键词： discrete element method die filling Forced feeding Stirrer design GPU computing

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Application of Connected Truck data to Evaluate Spatiotemporal Impact of Rest Area Closures on Ramp Parking

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Journal of Transportation Technologies 2024年第3期14卷 289-307页

作者： Jijo K. Mathew Jairaj desai edward d. Cox darcy M. Bullock Lyles School of Civil Engineering Purdue University West Lafayette IN USA Indiana department of Transportation Indianapolis IN USA

Ensuring adequate access to truck parking is critical to the safe and efficient movement of freight traffic. There are strict federal guidelines for commercial truck driver rest periods. Rest areas and private truck stops are the only places for the trucks to stop legally and safely. In locations without sufficient parking areas, trucks often park on interstate ramps, which create safety risks for other interstate motorists. Historically, agencies have employed costly and time intensive manual counting methods, camera surveillance, and driver surveys to assess truck parking. Connected truck data, available in near real-time, offers an efficient alternative to practitioners to assess truck parking patterns and identify areas where there may be insufficient safe parking spaces. This paper presents a case study of interstate I-70 in east central Indiana and documents the observed spatiotemporal impacts of a rest area closure on truck parking on nearby interstate ramps. Results showed that there was a 28% increase in parking on ramps during the rest area closure. Analysis also found that ramps closest to the rest area were most impacted by the closure, seeing a rise in truck parking sessions as high as 2.7 times. Parking duration on the ramps during rest area closure also increased drastically. Although it was expected that this would result in increased parking by trucks on adjacent ramps, this before, during, after scenario provided an ideal scenario to evaluate the robustness of these techniques to assess changing parking characteristics of long-haul commercial trucks. The data analytics and visualization tools presented in this study are scalable nationwide and will aid stakeholders in informed data-driven decision making when allocating resources towards improving the nations commercial vehicle parking infrastructure.

关键词： Connected Truck data Rest Areas Exit Ramps Truck Parking Commercial Vehicles

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Contraceptive behaviors and awareness in an urban slum community of south India

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Asian pacific Journal of Reproduction 2024年第4期13卷 160-168页

作者： Monica Albert Sekhar Shanthi edward Angeline Grace Sushmitha G Shirley Esther Priscilla department of Community Medicine Sree Balaji Medical College and Hospital(SBMCH)ChennaiIndia

Objective:To assess the factors associated with knowledge,attitude and behavior of contraception use among urban slum population in ***:A cross-sectional study was conducted in the urban slum of Anakaputhur,*** couples between ages of 19-49 years and living in slum areas were taken up for the study by simple random *** women,postnatal and postmenopausal women were excluded from the *** collection was done using a pretested structured questionnaire focusing on details regarding contraception knowledge,attitude,and *** analysis was done using IBM SPSS version *** test like Chi square and odds ratio(OR)were used to identify association between knowledge,attitude,and behavior of contraception with the associated variables and enter method of logistic regression analysis was ***:Out of the 360 respondents,228 were females,with a mean age of(34±5)*** 43%demonstrated adequate knowledge of contraception use,and 91%were aware of at least one contraceptive ***,72%exhibited a positive attitude towards contraceptive ***,43%(155 individuals)did not utilize any contraceptive *** contraceptive users,intrauterine devices were the most commonly adopted,followed by barrier methods and female *** was significant association between knowledge of contraception and education(aOR 7.29,95%CI 2.93-18.10,Pd socioeconomic class(aOR 3.66,95%CI 1.71-7.85,Pding attitude towards contraception use,education(aOR 8.54,95%CI 2.35-31.03,Pd number of children(aOR 10.04,95%CI 4.26-23.66,Pd a significant ***:These findings underscore the imperative for enhanced d

关键词： Family planning Unmet need Sterilization Knowledge Practice Urban slum

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Integrated Single-cell Multiomic Analysis of HIV Latency Reversal Reveals Novel Regulators of Viral Reactivation

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Genomics, Proteomics & Bioinformatics 2024年第1期22卷 67-88页

作者： Manickam Ashokkumar Wenwen Mei Jackson J.Peterson Yuriko Harigaya david M.Murdoch david M.Margolis Caleb Kornfein Alex Oesterling Zhicheng Guo Cynthia d.Rudin Yuchao Jiang edward P.Browne department of Medicine University of North Carolina at Chapel HillChapel HillNC 27599USA HIV Cure Center University of North Carolina at Chapel HillChapel HillNC 27599USA department of Biostatistics University of North Carolina at Chapel HillChapel HillNC 27599USA department of Microbiology and Immunology University of North Carolina at Chapel HillChapel HillNC 27599USA department of Genetics University of North Carolina at Chapel HillChapel HillNC 27599USA department of Medicine Duke UniversityDurhamNC 27708USA department of Computer Science Duke UniversityDurhamNC 27708USA department of Statistics Texas A&M UniversityCollege StationTX 77843USA department of Biology Texas A&M UniversityCollege StationTX 77843USA department of Biomedical Engineering Texas A&M UniversityCollege StationTX 77843USA

despite the success of antiretroviral therapy,human immunodeficiency virus(HIV)cannot be cured because of a reservoir of latently infected cells that evades *** understand the mechanisms of HIV latency,we employed an integrated single-cell RNA sequencing(scRNA-seq)and single-cell assay for transposase-accessible chromatin with sequencing(scATAC-seq)approach to simultaneously profile the transcriptomic and epigenomic characteristics of~125,000 latently infected primary Cd4^(+)T cells after reactivation using three different latency reversing *** expressed genes and differentially accessible motifs were used to examine transcriptional pathways and transcription factor(TF)activities across the cell *** identified cellular transcripts and TFs whose expression/activity was correlated with viral reactivation and demonstrated that a machine learning model trained on these data was 75%-79%accurate at predicting viral ***,we validated the role of two candidate HIV-regulating factors,FOXP1 and GATA3,in viral *** data demonstrate the power of integrated multimodal single-cell analysis to uncover novel relationships between host cell factors and HIV latency.

关键词： HIV latency reversal Primary Cd4þT cell Single-cell multiomics HIV-regulating factor Machine learning

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3d printing for ultra-precision machining:current status,opportunities,and future perspectives

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Frontiers of Mechanical Engineering 2024年第4期19卷 1-28页

作者： Tao HE Wai Sze YIP edward Hengzhou YAN Jiuxing TANG Muhammad REHAN Long TENG Chi Ho WONG Linhe SUN Baolong ZHANG Feng GUO Shaohe ZHANG Suet TO State Key Laboratory of Ultra-precision Machining Technology Department of Industrial and Systems EngineeringThe Hong Kong Polytechnic UniversityHong KongChina department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityHong KongChina department of Physics The Hong Kong University of Science and TechnologyHong KongChina School of Geosciences and Info-Physics Central South UniversityChangsha 410083China

Additive manufacturing,particularly 3d printing,has revolutionized the manufacturing industry by allowing the production of complex and intricate parts at a lower cost and with greater ***,3d-printed parts frequently require post-processing or integration with other machining technologies to achieve the desired surface finish,accuracy,and mechanical ***-precision machining(UPM)is a potential machining technology that addresses these challenges by enabling high surface quality,accuracy,and repeatability in 3d-printed *** study provides an overview of the current state of UPM for 3d printing,including the current UPM and 3d printing stages,and the application of UPM to 3d *** the presentation of current stage perspectives,this study presents a detailed discussion of the benefits of combining UPM with 3d printing and the opportunities for leveraging UPM on 3d printing or supporting each *** particular,future opportunities focus on cutting tools manufactured via 3d printing for UPM,UPM of 3d-printed components for real-world applications,and post-machining of 3d-printed ***,future prospects for integrating the two advanced manufacturing technologies into potential industries are *** study concludes that UPM is a promising technology for 3d-printed components,exhibiting the potential to improve the functionality and performance of 3d-printed products in various *** also discusses how UPM and 3d printing can complement each other.

关键词： ultra-precision machining 3d printing additive manufacturing future perspectives start-of-the-art-review

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Identification of novel mammalian viruses in tree shrews(Tupaia belangeri chinensis)

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Zoological Research 2024年第2期45卷 429-438页

作者： Hong Zhou Ren-Rong Tian Xiu-Rong Wang Jin-Xuan Yang Yun-Xiao Wang Ming-Liang Zhao Xu-dong Zhang Yu-Hua Ma Long-Bao Lv edward CHolmes Yong-Tang Zheng Wei-Feng Shi School of Clinical and Basic Medical Sciences Shandong First Medical University&Shandong Academy of Medical SciencesJi’nanShandong 250117China Key Laboratory of Emerging Infectious diseases in Universities of Shandong Shandong First Medical University and Shandong Academy of Medical SciencesTaianShandong 271000China Key Laboratory of Animal Models and Human disease Mechanisms of the Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common DiseasesCenter for Biosafety Mega-ScienceKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China School of Public Health Shandong First Medical University&Shandong Academy of Medical SciencesJi’nanShandong 250117China National Resource Center for Non-Human Primates Kunming Primate Research CenterKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650107China Sydney Institute for Infectious diseases School of Medical SciencesThe University of SydneySydneyNew South Wales 2006Australia department of Infectious diseases Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Shanghai Institute of Virology Shanghai Jiao Tong University School of MedicineShanghai 200025China

The Chinese tree shrew(Tupaia belangeri chinensis),a member of the mammalian order Scandentia,exhibits considerable similarities with primates,including humans,in aspects of its nervous,immune,and metabolic *** similarities have established the tree shrew as a promising experimental model for biomedical research on cancer,infectious diseases,metabolic disorders,and mental health ***,we used metatranscriptomic sequencing to analyze plasma,as well as oral and anal swab samples,from 105 healthy asymptomatic tree shrews to identify the presence of potential zoonotic *** total,eight mammalian viruses with complete genomes were identified,belonging to six viral families,including Flaviviridae,Hepeviridae,Parvovirinae,Picornaviridae,Sedoreoviridae,and ***,the presence of rotavirus was recorded in tree shrews for the first *** viruses-hepacivirus 1,parvovirus,and picornavirus-exhibited low genetic similarity(d viruses at the whole-genome scale,indicating ***,three other viruses-hepacivirus 2,hepatovirus A and hepevirus-exhibited high similarity(>94%)to known viral *** analyses also revealed that the rotavirus and mammalian orthoreovirus identified in this study may be novel *** findings provide insights into the diverse viral spectrum present in captive Chinese tree shrews,highlighting the necessity for further research into their potential for crossspecies transmission.

关键词： Tree shrew(Tupaia belangeri chinensis) Meta-transcriptomic sequencing Mammalian viruses Genomic analysis

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Sustainable oil-in-water analysis using a supercritical fluid carbon dioxide extraction system directly interfaced with infrared spectroscopy

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Journal of Environmental Sciences 2010年第9期22卷 1462-1468页

作者： edward d.Ramsey School of Chemical Engineering University of Science and Technology Liaoning

A direct aqueous supercritical fluid extraction （SFE） system using carbon dioxide provides a sustainable means by which a vast range of industries may continue to depend on well established infrared （IR） techniques to determine oil-in-water. The SFE-IR method provides an environmentally friendly substitute for current national standard IR reference methods for measuring oil-in-water that rely on using increasingly restricted ozone depleting solvents whose manufacture is being phased out in accordance with international law. The SFE-IR analysis of a 500 mL water sample can be accomplished in 15 min. A rapid on-line SFE-IR calibration method has been implemented. With this calibration method, SFE-IR accuracy for determining diesel oil in 500 mL spiked water samples using single wave number measurement was 86.0%-98.8% with precision （RSd） ranging from 2.5%-7.0%. Using a general purpose calculation which involves measuring infrared absorbance values at three different wave numbers, SFE-IR method accuracy for determining diesel oil in 500 mL spiked water samples was 83.7%-92.2% with RSd 1.0%-9.3%. data is presented that indicates current long established national standard IR reference methods involving three wave number calculations should be reviewed since, without careful consideration, the inclusion of calculated aromatic hydrocarbon species contributions to final oil-in-water concentration values may provide less accurate results.

关键词： oil-in-water supercritical fluid extraction infrared spectroscopy sustainable green technology

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The association of diet quality and physical activity with cardiovascular disease and mortality in 85,545 older Australians:A longitudinal study

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Journal of Sport and Health Science 2024年第6期13卷 841-850页

作者： ding ding Joe Van Buskirk Stephanie Partridge Philip Clare edward Giovannucci Adrian Bauman Nicole Freene Robyn Gallagher Binh Nguyen Sydney School of Public Health Faculty of Medicine and Healththe University of SydneyCamperdownNSW 2006Australia Charles Perkins Centre the University of SydneyCamperdownNSW 2006Australia Sydney Local Health district CamperdownNSW 2050Australia School of Health Sciences Faculty of Medicine and Healththe University of SydneyCamperdownNSW 2006Australia National drug and Alcohol Research Centre UNSW SydneySydneyNSW 2052Australia departments of Nutrition and Epidemiology Harvard T.H.Chan School of Public HealthBostonMA 02115USA Faculty of Health University of CanberraCanberraACT 2617Australia Susan Wakil School of Nursing and Midwifery the University of SydneyCamperdownNSW 2050Australia

Background:A quality diet and an active lifestyle are both important cornerstones of cardiovascular disease(CVd)***,despite their interlinked effects on metabolic health,the 2 behaviors are rarely considered jointly,particularly within the context of CVd *** examined the independent,interactive,and joint associations of diet and physical activity with CVd hospitalization,CVd mortality,and all-cause ***:CVd-free Australian participants aged 4574 years(n=85,545)reported physical activity,diet,sociodemographic,and lifestyle characteristics at baseline(20062009)and follow-up(20122015),and data were linked to hospitalization and death registries(03/31/2019 for CVd hospitalization and all-cause mortality and 12/08/2017 for CVd mortality).diet quality was categorized as low,medium,and high based on meeting dietary *** activity was operationalized as(a)total moderate-to-vigorous physical activity(MVPA)as per guidelines,and(b)the composition of MVPA as the ratio of vigorous-intensity physical activity(VPA)to total *** used a left-truncated cause-specific Cox proportional hazards model using time-varying ***:during a median of 10.7 years of follow-up,6576 participants were admitted to the hospital for CVd and 6581 died from all causes(876 from CVd during 9.3 years).A high-quality diet was associated with a 17%lower risk of all-cause mortality than a low-quality diet,and the highest MVPA category(compared with the lowest)was associated with a 44%and 48%lower risk of CVd and all-cause mortality,*** interactions between diet and physical activity were *** all outcomes,the lowest risk combinations involved a high-quality diet and the highest MVPA *** for total MVPA,some VPA was associated with further risk reduction of CVd hospitalization and all-cause ***:For CVd prevention and longevity,one should adhere to both a healthy d

关键词： diet Physical activity Cardiovascular disease Mortality Cohort studies

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Channel Flows in Plate Heat Exchangers with the Aid of Particle Tracking Velocimetry

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Open Journal of Fluid dynamics 2024年第3期14卷 163-183页

作者： Felipe José dos Santos Leonel edward Beckedorff Kleber Vieira de Paiva Jorge Luiz Goes Oliveira PETROBRASPetrleo Brasileiro S.A. Rio de Janeiro Brazil Institute of Fluid Mechanics and Heat Transfer Technische Universitt Wien Vienna Austria department of Mobility Engineering Federal University of Santa Catarina Joinville Brazil

Channel flows of Plate Heat Exchangers (PHEs) were assessed by experiments with three different chevron angle arrangements in turbulent regime. Two chevron angles were selected to assess low and high pressure drop channels, besides a third mixed configuration as to achieve in-between results regarding hydraulic performance. Friction factor correlations were provided with the channel Reynolds number ranging from 1175 to 8325. Two-dimensional (2d) mean velocity field was obtained by Particle Tracking Velocimetry (PTV) with Reynolds number equal to 3450. To the best of our knowledge, this is the first experimental study that quantified the complete 2d velocity field of a typical PHE channel. This value allowed comparison with literature results of Plate and Shell Heat Exchanger (PSHE) channels with the same Reynolds number. PSHE mean velocity field is highly heterogeneous as compared to the one obtained for PHE channels. Peak velocity magnitude in the PSHE center is 50% higher than its bulk velocity, whereas this value is only 15% higher in the PHE center. Pressure drop in PHE mixed channels cannot be approximated by averaging chevron angles: furrow flow prevailed in the specified conditions. The axial velocity is asymmetric regarding the vertical plane. Smooth streamlines prevail in the channel inlet. Recirculation zones at the channel exit affect pipe flow in the manifold outlet with swirling flow structures. The necessary length to obtain fully developed pipe flow at the channel outlet was estimated. Significant velocity components occur in the distribution areas and can limit the heat exchanger performance. The results reported herein are essential to understand how the PHE channel geometry affects the velocity field and, therefore, local heat transfer and dissipation processes.

关键词： PHE PTV PSHE Friction Factor Chevron

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