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Exploring the effects of coronary artery disease as a preexisting comorbidity on mortality in hospitalized septic patients:a retrospective observation study

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Emergency and Critical Care Medicine 2024年第2期4卷 47-51页

作者： Anmol Multani Greg stahl kerry Johnson Scott Goade robert D.Arnce College of Osteopathic Medicine Kansas City UniversityJoplinMOUSA Department of Data Improvement Freeman Health SystemJoplinMOUSA Department of Mathematics Missouri Southern State UniversityJoplinMOUSA Department of Pharmacy Freeman Health SystemJoplinMOUSA

Background:Sepsis has high prevalence and mortality rate,and it is imperative to identify populations at risk of poor sepsis *** patients with preexisting chronic comorbidities are shown to have worse sepsis *** identifying comorbidities with greater influence on sepsis progression,we can direct limited resources to septic patients with comorbidities and reduce health care *** comorbidities can impact the risk of developing sepsis and having worse *** artery disease(CAD)is a common comorbidity,especially in the elderly,and a leading cause of death *** wished to investigate the influence of CAD as a comorbidity on sepsis and hypothesized that preexisting CAD would increase mortality in hospitalized septic ***:We conducted retrospective observational study using patient data from Freeman Health System in Joplin,*** analyzed patient records from Freeman Health System database from January 1,2019,to June 30,*** patients were identified using the International Classification of Diseases,Tenth revision sepsis *** identify septic patients with preexisting CAD,we used International Classification of Diseases,Tenth revision codes for *** compared mortality rates for septic patients with and without ***:Two-sample proportion test was conducted to test the difference in mortality between septic patients with and without preexisting *** difference in mortality for the total population was−0.016(P=0.553).In the male and female subgroups,the differences in mortality were 0.0122(P=0.739)and−0.0511(P=0.208),*** differences in mortality in patients aged 40 to 64 years and 65 years and older were−0.0077(P=0.870)and 0.0007(P=0.983),*** statistical tests failed to find significant differences when comparing septic patients with and without preexisting *** was no significant difference in the age and sex ***:Our study showed that CAD alone was n

关键词： Comorbidity Coronary artery disease Inflammation Mortality rate in sepsis prognosis Sepsis

Challenges in determination of microscopic degree of cleanliness in ultra-clean gear steels

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Journal of Iron and Steel research(International) 2022年第10期29卷 1583-1600页

作者： D.Fuchs T.Tobie k.stahl Gear research Center(FZG) Technical University of Munich85748 GarchingGermany

Shot-peened,case-hardened gears can fail in the tooth root due to crack initiation below the surface of the steel ***,the crack is initiated at a non-metallic inclusion in the center of a so-called *** failure type can lead to a reduced endurance fatigue limit of the *** is for this reason that,over the last decade,much effort has been invested by steel manufacturers to reduce the non-metallic inclusion content of gear steels so as to mitigate or even completely prevent such crack *** ultra-clean gear steels were achieved by various measures in the steel production ***,as a result,the remaining non-metallic inclusions are inhomogeneously distributed in the steel volume in terms of both size and ***,due to the inhomogeneity of ultra-clean steels,the question arose if the values derived according to the standards are still representative of ultra-clean steel *** results show that the standards can still be applied,but more effort must be *** determine the degree of cleanliness,six microsections are currently evaluated according to steel test specification(SEP)1571,method *** is shown that an examination of 24 microsections starting from size class 0 seems beneficial to get more reliable and comparable results of the degree of cleanliness of these ultra-clean gear *** addition,it is shown that a high degree of cleanliness has been achieved for all steel batches investigated with the measures taken in the steel production process.

关键词： Degree of cleanliness Non-metallic inclusion Evaluation of inclusion SEP 1571 DIN 50602 Ultrasonic immersion testing Ultra-clean gear steel Gear

On the experimental characterization of the fluid volume influence on the friction between rough surfaces

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Friction 2023年第7期11卷 1334-1348页

作者： Lukas stahl Michael MÜLLEr Georg-Peter OSTErMEYEr Institute of Dynamics and Vibrations Technische Universität BraunschweigBraunschweig 37106Germany

The load-bearing behaviour of lubricated contacts depends primarily on the normal force,the relative velocity,and the ***,with the aid of the Stribeck curve,it is usually well possible to characterize whether hydrodynamics,mixed friction,or boundary friction is more likely to be *** fact that the load regime can also depend on the fluid quantity is obvious,but has hardly been systematically investigated so *** for contacts with microscopic roughness,the defined application of a very small amount of fluid is a very challenging *** this paper,a very fundamental study shows how a pin-on-disc tribometer can be used to achieve the transition from dry friction via mixed friction to predominant hydrodynamics by the amount of supplied *** experiments are carried out on samples filed with different *** addition,the simultaneous influence of partial filling and normal force as well as relative velocity is also *** good reproducibility has been practically reached over the entire range of the *** the quantities for the coefficient of friction(COF),it was concluded that close to full filling,a reduction of the fluid quantity has a similar effect on the COF as the reduction of the *** property goes along with the common theory of starved lubricated *** behaviour was not observed to the same extent for the normal *** the vicinity of smaller fluid quantities,the COF increases very rapidly with further reduction in fluid quantity,far more disproportionately than that with reduction in *** a deeper understanding of this problem,various practical issues such as idling or the run-up process in bearings can also be studied in a more focused manner.

关键词： starved lubrication Stribeck curve pin-on-disc tribometer fluid supply experimental studies

Numerical Visualization of Grease Flow in a Gearbox

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Chinese Journal of Mechanical Engineering 2023年第2期36卷 220-233页

作者： Hua Liu Florian Dangl Thomas Lohner karsten stahl School of Engineering&Design Department of Mechanical EngineeringTechnical University of MunichGear Research Center(FZG)BoltzmannstraBe1585748 Garching near MunichGermany

Lubricating greases are widely used in *** gear drives and gearboxes with difficult sealing *** efficiency and heat balance of grease-lubricated gearboxes depend strongly on the lubrication mechanisms channeling and circulating,for which the grease flow is *** computational fluid dynamics opens up the possibility to visualize and understand the grease flow in gearboxes in more *** this study,a single-stage gearbox lubricated with an NLGI 1-2 grease was modeled by the finite-volume method to numerically investigate the fluid *** show that the rotating gears influence the grease sump only locally around the *** a low grease fill volume,the rotation of the gears is widely separated from the grease *** a high grease fill volume,a pronounced geargrease interaction results in a circulating grease flow around the *** simulated grease distributions show good accordance with high-speed camera recordings.

关键词： Lubrication Grease Transmission Gearbox Computational fluid dynamics

A methodological framework for analyzing PPGIS data collected in 3D

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International Journal of Digital Earth 2023年第1期16卷 3435-3455页

作者： kamyar Hasanzadeh Nora Fagerholm Hans Skov-Petersen Anton stahl Olafsson Department of Geography and Geology University of TurkuTurkuFinland Department of Geosciences and Natural resource Management University of CopenhagenCopenhagenDenmark

Public participation geographic information system(PPGIS)is a facilitated Volunteered Geographic Information approach and data collection method that aims to capture the spatial experiences of *** we experience the space around us three-dimensionally,altitude,as the third dimension,has been often absent from PPGis research and *** is largely because of the complexity of implementing surveys in 3D but can also be attributed to a lack of analytical preparedness for using such *** study complements 3D PPGIS data collected from a pilot study of the Aninkainen block in Turku,Finland with synthetic,*** manufactured,data to propose an analytical framework for the study of 3D PPGIS *** analytical framework divides methods based on the geographical scale into two groups:micro-and macro-scale *** this framework,we propose the use of geospatial metrics to analyze 3D PPGIS *** argue that while this multidisciplinary area of research is in its infancy,use of intuitive 3D adapted geometric and landscape metrics can help overcome some of complexities associated with use of this emerging participatory *** conclude by outlining the limitations and envisioning areas for future research.

关键词： 3D GIS landscape metrics PPGIS

running‑In Behavior of Wet Multi‑plate Clutches:Introduction of a New Test Method for Investigation and Characterization

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Chinese Journal of Mechanical Engineering 2020年第2期33卷 152-160页

作者： katharina Voelkel Hermann Pflaum karsten stahl Gear research Centre(FZG) Technical University of MunichGarchingGermany

Wet multi-plate clutches are relevant components of modern drivetrain applications,not only in terms of function but also safety and *** at the beginning of their lifetime,distinct changes of the friction behavior may occur and make the actuation of the clutch *** transcript describes the typical running-in behavior of wet multi-plate clutches and gives a general definition for running-in of ***,a new test method to systematically investigate the running-in behavior of clutches is *** test method contains a test procedure to characterize the running-in behavior on different load ***,a multi-stage procedure to evaluate and characterize the running-in behavior of clutches with mathematical approaches and new characteristic values is *** quality of the test method is demonstrated on the example of three different tribological systems from dual clutch transmissions(DCT)and automatic transmissions(AT)application using paper friction linings.

关键词： Clutch running-in Test method Paper friction lining

Signaling transduction pathways involved in basophil adhesion and histamine release

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Chinese Medical Journal 2006年第2期119卷 122-130页

作者： SHA Quan Lars k. Poulsen Jens Gerwien NielsФdum Per stahl Skov Allergy Unit National University Hospital Copenhagen Denmark Allergy and Immunology research Center and Department of Medical Immunology Anhui Medical University Hefei 230032 China Institute of Medical Microbiology and Immunology University of Copenhagen Copenhagen Denmark reference Laboratory National University Hospital Copenhagen Denmark

Background Little is known about basophil with respect to the different signaling transduction pathways involved in spontaneous, cytokine or anti-IgE induced adhesion and how this compares to IgE-dependent and IgE-independent mediator secretion. The purpose of the present study was to investigate the roles of β1 and β2 integrins in basophil adhesion as well as hosphatidylinositol 3-kinase （PI3k）, src-kinases and extracellular signal regulated kinase （Erk）1/2 in basophil adhesion and histamine release （Hr）. Methods Basophils （purity of 10%-50%） were preincubated with anti-CD29 or anti-CD 18 blocking antibodies before used for adhesion study. Basophils were preincubated with the pharmacological inhibitors wortmannin, PP1, PD98059 before used for adhesion and Hr study. Cell adherence to bovine serum albumin （BSA） or fibronectin （Fn） was monitored using cell associated histamine as a basophil marker and the histamine was measured by the glass fiber assay. results Basophil spontaneous adhesion to Fn was inhibited by anti-CD29. Interleukin （IL）-3, granulocyte/macrophage colony stimulating factor （GM-CSF） induced adhesion to BSA was inhibited by anti-CD18. Wortmannin at 1 μmol/L and PP1 at 20 μmol/L strongly interfered with, whereas PD98059 at 50μmol/L weakly inhibited basophil spontaneous adhesion to Fn. One μmol/L wortmannin strongly inhibited IL-3, IL-5, GM-CSF and anti-IgE induced adhesion to BSA. PP1 at 20 μmol/L partly inhibited anti-IgE induced adhesion. Fifty μmol/L PD98059 marginally inhibited IL-5, weakly inhibited anti-IgE, partly inhibited GM-CSF induced adhesion. Wortmannin, PP1 and PD98059 inhibited anti-IgE （1：100 or 1：1000） induced basophil Hr in a dose dependent manner. They inhibited calcium ionophore A23187 （10 μmol/L, 5 μmol/L） induced basophil Hr in a dose dependent manner, but to different extend with PP1 being the most efficient. Conclusions Basophil spontaneous adhesion to Fn is mediated by β 1-integrins whereas cytokine induced adhesion to BSA is m

关键词： basophil signaling transduction adhesion histamine release

The diversity and ecological significance of microbial traits potentially involved in B_(12) biosynthesis in the global ocean

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mLife 2023年第4期2卷 416-427页

作者： Jiayin Zhou Wei Qin Xinda Lu Yunfeng Yang David stahl Nianzhi Jiao Jizhong Zhou Jihua Liu Qichao Tu Institute of Marine Science and Technology Shandong UniversityQingdaoChina Joint Lab for Ocean research and Education at Dalhousie University Shandong University and Xiamen UniversityQingdaoChina School of Biological Sciences University of OklahomaNormanOklahomaUSA Department of Civil and Environmental Engineering Massachusetts Institute of TechnologyCambridgeMassachusettsUSA State key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijingChina Department of Civil and Environmental Engineering University of WashingtonSeattleWashingtonUSA Institute of Marine Microbes and Ecospheres Xiamen UniversityXiamenChina Earth and Environmental Sciences Lawrence Berkeley NationalLaboratoryBerkeley CaliforniaUSA Institutefr Environmental Genomics University of OklahomaNormanOklahomaUSA School of Civil Engineering and Environmental Sciences University of OklahomaNormanOklahomaUSA School of Computer Sciences University of OklahomaNormanOklahomaUSA DermBiont Inc. BostonMassachusettsUSA

Cobalamin(B_(12)),an essential nutrient and growth cofactor for many living organisms on Earth,can be fully synthesized only by selected prokaryotes in ***,microbial communities related to B_(12) biosynthesis could serve as an example subsystem to disentangle the underlying ecological mechanisms balancing the function and taxonomic make-up of complex functional *** anchoring microbial traits potentially involved in B_(12) biosynthesis,we depict the biogeographic patterns of B_(12) biosynthesis genes and the taxa harboring them in the global ocean,despite the limitations of detecting de novo B_(12) synthesizers via metagenomes *** the taxonomic and functional composition of B_(12) biosynthesis genes were strongly shaped by depth,differentiating the epipelagic zones from the mesopelagic *** genes related to B_(12) biosynthesis were relatively stably distributed across different oceans,but the taxa harboring them varied considerably,showing clear functional redundancy among microbial *** taxa carrying B_(12) biosynthesis genes in the surface water were influenced by environmental factors such as temperature,oxygen,and ***,the composition of functional genes was only weakly associated with these environmental *** model analyses demonstrated that determinism governed the variations in B_(12) biosynthesis genes,whereas a higher degree of stochasticity was associated with taxonomic *** associations were observed between the chlorophyll a concentration and B_(12) biosynthesis,confirming its importance in primary production in the global *** results of this study reveal an essential ecological mechanism governing the assembly of microbes in nature:the environment selects for function rather than taxonomy;functional redundancy underlies stochastic community assembly.

关键词： B_(12)biosynthesis community assembly functional genes functional redundancy ocean primary production

A bioactive compliant vascular graft modulates macrophage polarization and maintains patency with robust vascular remodeling

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Bioactive Materials 2023年第1期19卷 167-178页

作者： Alexander stahl Dake Hao Janos Barrera Dominic Henn Sien Lin Seyedsina Moeinzadeh Sungwoo kim William Maloney Geoffrey Gurtner Aijun Wang Yunzhi Peter Yang Department of Orthopaedic Surgery Stanford University240 Pasteur DriveStanfordCA94304USA Department of Chemistry Stanford University121 Mudd BuildingStanfordCA94305USA Department of Surgery School of MedicineUniversity of California DavisSacramentoCA95817USA Institute for Pediatric regenerative Medicine Shriners Hospitals for ChildrenSacramentoCA95817USA Department of Surgery Stanford University300 Pasteur DriveStanfordCA94305USA Department of Biomedical Engineering University of California DavisDavisCA95616USA Department of Materials Science and Engineering Stanford University496 Lomita MallStanfordCA94305USA Department of Bioengineering Stanford University443 Via OrtegaStanfordCA4305USA

Conventional synthetic vascular grafts are associated with significant failure rates due to their mismatched mechanical properties with the native vessel and poor regenerative *** different tissue engineering approaches have been used to improve the biocompatibility of synthetic vascular grafts,it is still crucial to develop a new generation of synthetic grafts that can match the dynamics of native vessel and direct the host response to achieve robust vascular *** size of pores within implanted biomaterials has shown significant effects on macrophage polarization,which has been further confirmed as necessary for efficient vascular formation and ***,we developed biodegradable,autoclavable synthetic vascular grafts from a new polyurethane elastomer and tailored the grafts’interconnected pore sizes to promote macrophage populations with a pro-regenerative phenotype and improve vascular regeneration and patency *** synthetic vascular grafts showed similar mechanical properties to native blood vessels,encouraged macrophage populations with varying M2 to M1 phenotypic expression,and maintained patency and vascular regeneration in a one-month rat carotid interposition model and in a four-month rat aortic interposition *** innovative bioactive synthetic vascular graft holds promise to treat clinical vascular diseases.

关键词： Vascular graft Vascular compliance Pore size Macrophage polarization Vascular remodeling