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Friction and wear performance of polyether ether ketone(PEEK)polymers in three lubrication regimes

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Friction 2024年第4期12卷 670-682页

作者： Davide MASSOCCHI nora LECIS Marco LATTUADA Davide SCAGLIA steven CHATTERTOn Paolo PEnnACCHI Department of Mechanical Engineering Politecnico di MilanoMilan 20156Italy Eni SpA Downstream product R&DLombardia 20097Italy Eurobearings S.R.L. Lombardia 29016Italy

This experimental study investigates the friction and wear of three coatings commonly used in industrial applications,particularly in hydrodynamic *** three materials under investigation were Babbitt,polyether ether ketone(PEEK)reinforced with 15%carbon fibers,and PEEK reinforced with 20%carbon *** first polymer material was extruded,while the other was produced by fused deposition modelling(FDM).The materials were subjected to sliding tests in a pin-on-disc configuration,with a steel ball serving as the counter *** tests were conducted at room temperature,with a load of 10 n and under three different lubrication conditions:dry,grease,and *** linear speed was set at 0.3 m/s for the dry and semi-solid lubrication tests,while for the oil tests,the speed was set at 0.25 m/*** greases used had consistency grades of nGLI 000 and nGLI *** ISO VG 68 circulation oil was used for the oil lubrication ***,thermodynamic analyses were performed under the most severe conditions(i.e.,dry)to investigate the steel-Babbitt and steel-PEEK contact.

关键词： hydrodynamic bearings polyether ether ketone(PEEK)polymers additive manufacturing grease lubrication sliding oil lubrication ball-on-disk tribology

Hepatic angiotensin-converting enzyme 2 expression in metabolic dysfunction-associated steatotic liver disease and in patients with fatal COVID-19

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World Journal of Gastroenterology 2024年第31期30卷 3705-3716页

作者： Angus K Jacobs steven D Morley Kay Samuel Katie Morgan Lyndsey Boswell Timothy J Kendall David A Dorward Jonathan A Fallowfield Peter C Hayes John n Plevris Hepatology Laboratory University of EdinburghEdinburgh EH164SBUnited Kingdom Scottish national Blood Transfusion Service Jack Copland CentreEdinburgh EH144BEUnited Kingdom Institute for Regeneration and Repair University of EdinburghEdinburgh EH164UUUnited Kingdom Edinburgh Pathology University of EdinburghEdinburgh EH164SBUnited Kingdom

BACKGROUnD Metabolic dysfunction-associated steatotic liver disease(MASLD),characterised by hepatic lipid accumulation,causes inflammation and oxidative stress accompanied by cell damage and *** injury(LI)is also frequently reported in patients hospitalised with coronavirus disease 2019(COVID-19),while preexisting MASLD increases the risk of LI and the development of COVID-19-associated *** of injury at the cellular level remain unclear,but it may be significant that severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)which causes COVID-19,uses angiotensin-converting expression enzyme 2(ACE2),a key regulator of the‘anti-inflammatory’arm of the renin-angiotensin system,for viral attachment and host cell *** To determine if hepatic ACE2 levels are altered during progression of MASLD and in patients who died with severe *** ACE2 protein levels and localisation,and histological fibrosis and lipid droplet accumulation as markers of MASLD were determined in formalin-fixed liver tissue sections across the MASLD pathological spectrum(isolated hepatocellular steatosis,metabolic dysfunction-associated steatohepatitis(MASH)+/-fibrosis,end-stage cirrhosis)and in post-mortem tissues from patients who had died with severe COVID-19,using ACE2 immunohistochemistry and haematoxylin and eosin and picrosirius red staining of total collagen and lipid droplet areas,followed by quantification using machine learning-based image pixel *** ACE2 staining is primarily intracellular and concentrated in the cytoplasm of centrilobular hepatocytes and apical membranes of bile duct ***,ACE2 protein levels are elevated in non-fibrotic MASH compared to healthy controls but not in the progression to MASH with fibrosis and in ***2 protein levels and histological fibrosis are not associated,but ACE2 and liver lipid droplet content are significantly correlated across the MASLD *** A

关键词： Metabolic dysfunction-associated steatotic liver disease Angiotensin-converting enzyme 2 Immunohistochemistry COVID-19 COVID-19-associated cholangiopathy

Thermodynamic analysis of metal segregation in dual phase high entropy ceramics

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Journal of Materiomics 2024年第4期10卷 889-895页

作者： steven M.Smith II William G.Fahrenholtz Gregory E.Hilmas Stefano Curtarolo Missouri University of Science and Technology Materials Science and Engineering DepartmentRollaMO65409USA Duke University Department of Mechanical Engineering and Materials ScienceDurhamNC27708USA Duke University Center of Autonomous Materials DesignDurhamNC27708USA

Equilibrium Gibbs'free energy calculations were used to determine metal segregation trends between boride and carbide solid solutions containing two metals that are relevant to dual phase high entropy *** model predicted that Ti had the strongest tendency to segregate to the boride phase followed by Zr,nb,Mo,V,Hf,and Ta,which matches experimental results of measured *** ratio of a metal in the carbide phase to the content of the same metal in the corresponding metal boride had a linear trend with the change in standard Gibbs'free energy of reaction for a metal carbide reacting with B_(4)C to produce its corresponding metal boride and *** proposed model was used to predict the changes in standard Gibbs'free energy for CrC→CrB_(2) to be−260 kJ and WC→WB_(2) to be 148 kJ,which indicates that Cr has the strongest segregation to the boride and W has the strongest segregation to the *** proposed model can be used to estimate the segregation of metals in dual phase high entropy boride-carbide ceramics of any boride/carbide ratio or metal content.

关键词： Dual phase High entropy ceramic Boride Carbide Thermodynamics

Empirically evaluating virtual reality’s effect on reservoir engineering tasks

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Visual Informatics 2024年第1期8卷 26-46页

作者： Bryson Lawton nanjia Wang steven Samoil Parisa Daeijavad Siqi Xie Zhangxin Chen Frank Maurer Department of Computer Science University of Calgary2500 University Dr NWCalgaryT2N 1N4AlbertaCanada Department of Chemical&Petroleum Engineering University of Calgary2500 University Dr NWCalgaryT2N 1N4AlbertaCanada

To help determine in what ways virtual reality(VR)technologies may benefit reservoir engineering workflows,we conducted a usability study on a prototype VR tool for performing reservoir model analysis *** leveraging the strengths of VR technologies,this tool’s aim is to help advance reservoir analysis workflows beyond conventional methods by improving how one understands,analyzes,and interacts with reservoir model *** evaluate our tool’s VR approach to this,the study presented herein was conducted with reservoir engineering experts who used the VR tool to perform three common reservoir model analysis tasks:the spatial filtering of model cells using movable planes,the cross-comparison of multiple models,and well path *** study found that accomplishing these tasks with the VR tool was generally regarded as easier,quicker,more effective,and more intuitive than traditional model analysis software while maintaining a feeling of low task workload on ***,participants provided positive feedback regarding their experience with using VR to perform reservoir engineering work tasks,and in general,it was found to improve multi-model cross-analysis and rough object manipulation in *** indicates the potential for VR to be better than conventional means for some work tasks and participants also expressed they could see it best utilized as an addition to current software in their reservoir model analysis *** were,however,some concerns voiced when considering the full adoption of VR into their work that would be best first addressed before this took place.

关键词： Immersive analytics Visual analytics Data visualization Reservoir engineering Virtual reality VR

Orientation Bias of Self-Assembled Alkanes and Their Derivatives Under Dynamic Lateral nanoconfinement Conditions

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CCS Chemistry 2024年第4期6卷 1024-1033页

作者： Conditions Lihua Yu Yuanzhi Xia Tianze Hu Brent Daelemans steven De Feyter Department of Chemistry Division of Molecular Imaging and PhotonicsKU LeuvenB-3001 Leuven

Self-assembled molecular networks(SAMns)formed on crystalline solid substrates result from the spontaneous arrangement of individual molecules into structured *** interaction between molecules and the substrate leads to a nonrandom orientation of SAMns with respect to the substrate’s *** the case of graphite,the sixfold rotational symmetry of the substrate results in an equivalent rotational degeneracy in the orientation of *** this study,we explored how nanoconfinement,that is,the restriction of SAMn formation to nanometersized areas,known as nanocorrals,could impact and potentially alleviate the orientational degeneracy of SAMns,with emphasis on the influence of molecule symmetry,size,and intermolecular *** this end,we investigated the orientation distribution of n-alkanes and functionalized alkanes within nanocorrals,which were fabricated using scanning tunneling microscopy lithography(nanoshaving).We observed lifting of orientational degeneracy for long alkanes,contrary to shorter alkanes,which did not exhibit this orientation ***,functionalized alkanes with hydrogen bonding groups demonstrated preferential alignment regardless of length,highlighting the significance of stabilizing intermolecular interactions in the alignment *** study discussed the underlying principles of the molecular packing process and shed light on the complexity of molecular self-assembly in nanoconfined spaces.

关键词： self-assembly confinement condition nanocorral orientation bias scanning tunneling microscopy

nutritional epigenetics education improves diet and attitude of parents of children with autism or attention deficit/hyperactivity disorder

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World Journal of Psychiatry 2024年第1期14卷 159-178页

作者： Renee J Dufault Katherine M Adler David O Carpenter steven G Gilbert Raquel A Crider College of Graduate Health Studies A.T.Still UniversityKirksvilleMO 63501United States Department of Research Food Ingredient and Health Research InstituteNaalehuHI 96772United States Department of Health Sciences University of New HavenWest HavenCT 06516United States Institute for Health and the Environment School of Public HealthState University of New YorkAlbanyNY 12222United States Department of Research Institute of Neurotoxicology and Neurological DisordersSeattleWA 98105United States Department of Statistics Food Ingredient and Health Research InstituteNaalehuHI 96772United States

BACKGROUnD Unhealthy maternal diet leads to heavy metal exposures from the consumption of ultra-processed foods that may impact gene behavior across generations,creating conditions for the neurodevelopmental disorders known as autism and attention deficit/hyperactivity disorder(ADHD).Children with these disorders have difficulty metabolizing and excreting heavy metals from their bloodstream,and the severity of their symptoms correlates with the heavy metal levels measured in their *** may play a key role in helping parents reduce their ultra-processed food and dietary heavy metal intake by providing access to effective nutritional epigenetics *** To test the efficacy of nutritional epigenetics instruction in reducing parental ultra-processed food *** The study utilized a semi-randomized test and control group pretest-posttest pilot study design with participants recruited from parents having a learning-disabled child with autism or ***-two parents who met the inclusion criteria were randomly selected to serve in the test(n=11)or control(n=11)*** test group participated in the six-week online nutritional epigenetics tutorial,while the control group did *** efficacy of the nutritional epigenetics instruction was determined by measuring changes in parent diet and attitude using data derived from an online diet survey administered to the participants during the pre and post intervention *** intake scores were derived for both ultra-processed and whole/organic *** sample t-tests were conducted to determine any differences in mean diet scores within each *** There was a significant difference in the diet scores of the test group between the pre-and post-intervention *** parents in the test group significantly reduced their intake of ultra-processed foods with a preintervention diet score of 70(mean=5.385,SD=2.534)and a post-intervention diet score of 113(mean=8.692,SD=1.750)and the

关键词： Epigenomics Parenteral nutrition Autism Attention deficit/hyperactivity disorder Ultra-processed foods Heavy metals

Development and application of photocatalytic coating for roadside nO_(x) mitigation in Hong Kong

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Chinese Chemical Letters 2024年第3期35卷 153-157页

作者： Xinwei Li Pengge Wang Shuwen Han Yu Huang Wingkei Ho steven Sai Hang Ho Shun-cheng Lee Meng Wang Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina State Key Laboratory of Loess and Quaternary Geology(SKLLQG)and Key Laboratory of Aerosol Chemistry and Physics Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China Department of Science and Environmental Studies The Education University of Hong KongHong KongChina Division of Atmospheric Sciences Desert Research InstituteRenoNV 89512United States

A facile chemical method for the development of photocatalytic coating products was proposed based on practical application perspective for the Hong Kong roadside nitrogen oxides(nO_(x))***_(2)-based photocatalytic coating PC-C film with crystallized size of around 5–6 nm was synthesized with the peptization of H_(2)O_(2).The PC-C coating possesses a super-hydrophilicity surface and is proven to have a nO_(x)degradation rate of 46.8%with an optimum pH level of *** addition,the PC-C coating presents a promising photocatalytic nO_(x)degradation compared with other commercially available coating products and P25 when applied on two building materials of poly-methyl methacrylate(PMMA)and concrete surface.A weather resistance simulation and a 180-day on-site field trial were carried out the attenuation effects of photocatalytic coating applied in outdoor *** on epidemiological estimation and field investigation,hospital admissions for respiratory diseases(HARD)and mortality cases(MC)could be reduced with the application of PC-C coating along the street *** work demonstrates the feasibility of air pollution control measures for the local roadside nO_(x)using photocatalytic technology,offering promising health benefits with environmental remediation.

关键词： Photocatalysis Coating nO_(x) mitigation Hong Kong Roadside

Application of sentiment and word frequency analysis of physician review sites to evaluate refractive surgery care

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Advances in Ophthalmology Practice and Research 2024年第2期4卷 78-83页

作者： Victoria Vought Rita Vought Andrew S.Lee Irene Zhou Mansi Garneni steven A.Greenstein Institute of Ophthalmology and Visual Science Rutgers New Jersey Medical SchoolNewarkNJUSA Washington University School of Medicine St.LouisMOUSA Cornea and Laser Eye Institute TeaneckNJUSA

Background:Online physician reviews increase transparency in health care,helping patients make informed de-cisions about their *** processing techniques can quantify this data and allow providers to better understand patients'experiences,perspectives,and *** objective of this study was to assess patient satisfaction and understand the aspects of care that are valued by patients seeking refractive care using sentiment and word frequency ***:Written reviews and Star ratings for members of the Refractive Surgery Alliance Society practicing in the United States were collected from Healthgrades,a popular physician rating *** with at least one written review were included in the *** were scored from-1(most negative)to+1(most positive)using Valence Aware Dictionary sEntiment Reasoner(VADER).Reviews were stratified by demographic charac-teristics,namely gender,region,and years in *** frequency analysis was applied to find the most common words and ***:A total of 254 specialists and 3104 reviews were analyzed,with an average of 4.4/5 stars and mean 48 ratings *** physicians had positive reviews(96%,average VADER=0.69).Younger physicians(nce residency)had significantly higher Stars rating than senior peers(>20 years)(Pnd was observed in VADER score(0.71 vs 0.69),although not statistically significant(P=0.06).no statistical differences were observed between Stars rating and VADER score by gender(P=0.66,P=0.83)or by geographical region(P=0.74,P=0.07)."Staff"(n=1269),"professional"(n=631),"office"(n=523),"questions"(n=424),and"friendly"(n=386)were frequently used in reviews,along with phrases such as"the staff"(n=273)and"my questions"(n=174)."Surgery"(n=719),"staff"(n=576),"procedure"(n=251),"experience"(n=243),and"professional"(n=240)were the most common words in positive reviews,while"surgery"(n=147),"office"(n=86),"staff"(n=54),"time"(n=47),and"insurance"(

关键词： Patient sentiment Quality improvement Physician reviews

non-genetic contributions of the sperm nucleus to embryonic development

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Asian Journal of Andrology 2011年第1期13卷 31-35页

作者： Yasuhiro Yamauchi Jeffrey A Shaman W steven ward Department Anatomy and Reproductive Biology Institute for Biogenesis Research John A. Burns School of Medicine University of Hawaii at Manoa Honolulu HI USA GLP Services GENEWlZ Inc. 115 Corporate Blvd. South Plainfield NJ 07080 USA

Recent data from several laboratories have provided evidence that the newly fertilized oocyte inherits epigenetic signals from the sperm chromatin that are required for proper embryonic development. For the purposes of this review, the term epigenetic is used to describe all types of molecular information that are transmitted from the sperm cell to the embryo. There are at least six different forms of epigenetic information that have already been established as being required for proper embryogenesis in mammals or for which there is evidence that it may do so. These are （i） DnA methylation; （ii） sperm-specific histones, （iii） other chromatin-associated proteins; （iv） the perinuclear theca proteins; （v） sperm-born RnAs and, the focus of this review; and （vi） the DnA loop domain organization by the sperm nuclear matrix. These epigenetic signals should he considered when designing protocols for the manipulation and cryopreservation of spermatozoa for assisted reproductive technology as necessary components for effective fertilization and subsequent embryo development.

关键词： embryogenesis epigenetics sperm DnA sperm nuclear matrix DnA loop domain organization