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Friction 2024年第4期12卷 812-822页

作者： MichałWASILCZUK MichałWODTKE Faculty of Mechanical Engineering and Ship Technology Gdańsk University of TechnologyGdańsk 80-233Poland

In hydrodynamic bearings traditional bearing alloys:Babbitts and bronzes are most frequently *** sliding layers are sometimes applied as a valuable *** diamond-like carbon(DLC)coatings,which are also considered for certain applications may show some advantages,as *** material selection is of secondary importance in a full film lubrication regime it becomes important in mixed friction conditions,which is crucial for bearings with frequent starts and *** research aimed at studying the performance of fluid film bearings in the specific operating regime,including the transition to mixed friction,is described in the *** tests were carried out on four tilting pad bearings of different material compositions:Steel/bronze,DLC/steel,steel/polyether ether ketone(PEEK),and steel/*** tests comprised stopping under load and reproduction of the Stribeck curve by decreasing rotational speed to very low values,and observing the changes of friction force during the transition to mixed friction *** of the transition conditions and other results showed clear differences between the tested bearings,illustrating the feasibility of less popular material compositions for bearings operating in specific *** specifically,the DLC/steel bearing was demonstrating superior performance,*** friction,transition to mixed friction occurring at higher load,and more stable performance at start-stop regime over the other tested bearings.

关键词： tilting pad thrust bearing experimental research start-stop regime polyether ether ketone(PEEK) diamond-like carbon(DLC)coating metallic bearing alloys

Adaptive Optimal Discrete-Time Output-Feedback Using an Internal Model Principle and Adaptive Dynamic Programming

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 131-140页

作者： Zhongyang Wang Youqing Wang Zdzisław Kowalczuk the College of Information Science and Technology Beijing University of Chemical TechnologyBeijing 100029China IEEE the Department of Robotics and Decision Systems Faculty of ElectronicsTelecommunications and InformaticsGdańsk University of TechnologyGdansk 80-233Poland

In order to address the output feedback issue for linear discrete-time systems, this work suggests a brand-new adaptive dynamic programming(ADP) technique based on the internal model principle(IMP). The proposed method, termed as IMP-ADP, does not require complete state feedback-merely the measurement of input and output data. More specifically, based on the IMP, the output control problem can first be converted into a stabilization problem. We then design an observer to reproduce the full state of the system by measuring the inputs and outputs. Moreover, this technique includes both a policy iteration algorithm and a value iteration algorithm to determine the optimal feedback gain without using a dynamic system model. It is important that with this concept one does not need to solve the regulator equation. Finally, this control method was tested on an inverter system of grid-connected LCLs to demonstrate that the proposed method provides the desired performance in terms of both tracking and disturbance rejection.

关键词： Adaptive dynamic programming(ADP) internal model principle(IMP) output feedback problem policy iteration(PI) value iteration(VI)

Enhancing diaphragmatic defect repair and regeneration:How biomaterials leading the way to progress?

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BMEMat(BioMedical Engineering Materials) 2024年第3期2卷 92-107页

作者： Mojtaba Farahani Przemysław Gnatowski Raziyeh Najafloo Tina Navaei Edyta Piłat Justyna Kucińska-Lipka Mohammad Reza Saeb Masoud Mozafari Institute of Biomedical Engineering Department of Pharmacology and PhysiologyFaculty of MedicineUniversity of MontrealMontrealCanada Research Center Centre Hospitalier Universitaire Sainte-JustineMontrealCanada Department of Polymer Technology Faculty of ChemistryGdańsk University of TechnologyGdańskPoland Faculty of Sustainable Design Engineering University of Prince Edward IslandCharlottetownCanada Department of Pharmaceutical Chemistry Medical University of GdańskGdańskPoland Research Unit of Medical Imaging Physics and TechnologyFaculty of MedicineUniversity of OuluOuluFinland

Physicians encounter significant challenges in dealing with large diaphragmatic defects in both pediatric and adult *** hernias,such as Morgagni,Bochdalek,and Hiatus hernias,can result in congenital lesions that are often undiagnosed until the appearance of symptoms(bleeding,anemia,and acid reflux).Therefore,substantial potential exists for developing tissue-engineered constructs as novel therapeutic options in *** research indicates promising mid-term performance for both natural and synthetic ***,studies exploring their application in diaphragm regeneration are limited and remain in the early research ***,further investigation is required to address the constraints in human tissue supply for clinical *** article comprehensively reviews the role of biomaterials in diaphragmatic tissue repair and *** emphasizes biomaterials,including biomimetic polymers used in technological *** summary will enable researchers to critically assess the capability of existing natural biomaterials as essential tissueengineered patches for clinical use.

关键词： biomaterials diaphragm diaphragmatic defects hernia scaffolds

Unraveling the potential of acute intermittent hypoxia as a strategy for inducing robust repair in multiple sclerosis

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Neural Regeneration Research 2024年第11期19卷 2339-2340页

作者： Valerie M.K.Verge Nataliya Tokarska Justin M.Naniong Department of Anatomy Physiology and PharmacologyUniversity of SaskatchewanSaskatoonSKCanada Cameco MS Neuroscience Research Center University of SaskatchewanSaskatoonSKCanada

Multiple sclerosis(MS)is a debilitating inflammatory disease of the central nervous system characterized by immune-mediated segmental demyelination and variable degrees of axonal and neuronal degeneration that contribute to *** efficient and effective repair programs following demyelination is a major goal and challenge in *** MS therapies focus largely on modulating the immune aspects of the disease contributing to *** this alleviates some symptoms and mitigates damage,it does not tackle the fundamental challenge of effective remyelination,which few MS patients experience,especially in the progressive phase of the disease.

关键词： sclerosis degeneration damage

Bone graft incorporation failure with inappropriate limb load transfer can lead to aseptic acetabular loosening of metal-on-metal prosthesis: A case report

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World Journal of Orthopedics 2024年第7期15卷 668-674页

作者： RafałStanisław Domagalski Bogdan Dugiełło Sonia Rokicka Szymon Czech Rafałskowroński Dominika Rokicka Marta Patrycja Wróbel Krzysztof Strojek Tomasz Stołtny District Hospital of Orthopaedics and Trauma Surgery in PiekaryŚląskie PiekaryŚląskie 41-940Poland District Railway Hospital Medical University of SilesiaKatowice 40-760Poland Faculty of Medicine Medical University of GdańskGdańsk 80-210Poland “ALFA”Orthopaedics and Traumatology Center Białystok 15-763Poland Department of Internal Medicine Diabetology and Cardiometabolic DisordersFaculty of Medical Sciences ZabrzeMedical University of SilesiaZabrze 41-800Poland

BACKGROUND Aseptic acetabular loosening can result from various factors that can be categorized into groups:patient-related,surgeon-related and *** present a case of a 63-year-old patient who at first underwent a total hip arthro-plasty(THA)using a metal-on-metal bearing due to hip ***-up visits revealed no complications after the *** years after the THA,acetabular component loosening occurred due to subsequent trauma of the opposite hip,necessitating a revision THA using a ceramic-on-ceramic *** SUMMARY We aim to illustrate a rare case where the primary reason for undergoing THA revision was not only incomplete bone graft incorporation but also improper limb load *** the revision arthroplasty,a 9-year follow-up visit revealed improvements in all evaluation measures on questionnaire compared to the state before surgery:Harris Hip Score(before surgery:15;after surgery:95),Western Ontario and McMaster Universities Arthritis Index(before surgery:96;after surgery:0),and Visual Analogue Scale(before surgery:10;after surgery:1).CONCLUSION Opposite-hip trauma caused a weight transfer to the limb after a THA *** process led to a stress shielding effect,resulting in acetabular component loosening.

关键词： Acetabular loosening Limb load Stress shielding effect Revision hip arthroplasty Case report

Synchrotron X-ray micro-computed tomography imaging of solid bridges between potash particles near contact points

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Particuology 2024年第9期92卷 24-29页

作者： Mojtaba Nabipoor Hassankiadeh Mohammad Mehdi Heydari Carter Blocka Lifeng Zhang Department of Chemical and Biological Engineering University of SaskatchewanSKS7N 5A9SaskatoonCanada

Chemical fertilizers,such as potash,have a strong tendency to cake when exposed to *** this work,a novel synchrotron-based X-ray tomography 3D-imaging technique was for the first time employed to investigate the solid bridge formation from 2D and 3D *** processing and a theoretical model were presented to demonstrate recrystallization near contact points between potash particles during a conventional drying *** effect of initial moisture content on the water activity of surface surrounding the contact points was *** results showed that by increasing the moisture content of particles(3%–5%),the dissolution of sylvite increased and the solid bridge length between potash particles was enlarged from 28μm to 44μm due to supersaturation *** addition,the external porosity of potash particles at the end of drying process decreased from 25.3%to 19.5%for 3%and 5%moisture content,respectively.

关键词： Potash fertilizer Solid bridge Recrystallization Synchrotron X-ray micro-CT imaging Drying process

Emerging role of galectin 3 in neuroinflammation and neurodegeneration

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Neural Regeneration Research 2024年第9期19卷 2004-2009页

作者： Brian M.Lozinski Khanh Ta Yifei Dong Department of Clinical Neuroscience University of CalgaryCalgaryABCanada Deparment of Biochemistry Microbiology&ImmunologyUniversity of SaskatchewanSaskatoonSKCanada

Neuroinflammation and neurodegeneration are key processes that mediate the development and progression of neurological ***,the mechanisms modulating these processes in different diseases remain incompletely *** in single cell based multi-omic analyses have helped to identify distinct molecular signatures such as Lgals3 that is associated with neuroinflammation and neurodegeneration in the central nervous system(CNS).Lgals3 encodes galectin-3(Gal3),aβ-galactoside and glycan binding glycoprotein that is frequently upregulated by reactive microglia/macrophages in the CNS during various neurological *** Gal3 has previously been associated with non-CNS inflammatory and fibrotic diseases,recent studies highlight Gal3 as a prominent regulator of inflammation and neuroaxonal damage in the CNS during diseases such as multiple sclerosis,Alzheimer’s disease,and Parkinson’s *** this review,we summarize the pleiotropic functions of Gal3 and discuss evidence that demonstrates its detrimental role in neuroinflammation and neurodegeneration during different neurological *** also consider the challenges of translating preclinical observations into targeting Gal3 in the human CNS.

关键词： Alzheimer’s disease Galectin 3 microglia multiple sclerosis neurodegeneration neuroinflammation Parkinson’s disease therapeutics

Exploring the effects of anthropogenic disturbance on predator inspection activity in Trinidadian guppies

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Current Zoology 2024年第1期70卷 109-111页

作者： Alix J.P Brusseau Laurence E.A.Feyten Adam L.Crane Grant E.Brown Department of Biology Concordia UniversityMontrealQCH4B 1R6Canada Department of Biomedical Sciences WCVMUniversity of SaskatchewanSaskatoonSKCanada

Prey animals are often faced with uncertainty due to having imperfect information regarding current local conditions,including predation risks and the availability of reliable foraging opportunities(Dall 2010).As this uncertainty increases,the probability of making costly behavioral errors also increases,leading to more risk averse behavioral tactics(Feyten et al.2019).For example,Trinidadian guppies Poecilia reticulata are far more risk averse when faced with multiple unknown sources of risk assessment information than when faced with a mix of known and unknown cues(Feyten et al.2019).Prey can reduce uncertainty by gathering and integrating private and social information regarding current risk levels within microhabitats(Dall 2010;Munoz and Blumstein 2012).

关键词： human disturbance information availability information reliability predator-prey interactions risk assessment uncertainty

Hierarchical Control Strategy for Load Regulation Based on Stackelberg Game Theory Considering Randomness

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 929-941页

作者： Tingyu Jiang Ping Ju C.Y.Chung Yuzhong Gong College of Energy and Electrical Engineering Hohai UniversityNanjing 211100China Department of Electrical Engineering City University of Hong KongHong Kong CF624China Department of Electrical and Computer Engineering University of SaskatchewanSaskatoonSK S7N 5A9Canada CSEE IEEE

Demand response has been recognized as a valuable functionality of power systems for mitigating power *** paper proposes a hierarchical control strategy among the distribution system operator(DSO),load aggregators(LAs),and thermostatically controlled loads(TCLs);the strategy includes a scheduling layer and an executive layer to provide load *** the scheduling layer,the DSO(leader)offers compensation price(CP)strategies,and the LAs(followers)respond to CP strategies with available regulation power(ARP)*** of the DSO and LAs are modeled according to their behaviors during the load regulation *** game is adopted to capture interactions among the players and leader and to obtain the optimal strategy for each participant to achieve ***,considering inevitable random factors in practice,e.g.,renewable generation and behavior of users,two different stochastic models based on sample average approximation(SAA)and parameter modification are formulated with improved scheduling *** the executive layer,distributed TCLs are triggered based on strategies determined in the scheduling layer.A self-triggering method that does not violate user privacy is presented,where TCLs receive external signals from the LA and independently determine whether to alter their operation *** simulations are performed on the modified IEEE-24 bus system to verify effectiveness of the proposed strategy.

关键词： Demand response hierarchical control load regulation self-triggering method Stackelberg game

Type 2 Diabetes—Hard to Select a Healthy Choice

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Health 2024年第1期16卷 1-8页

作者： Stefan Backe Department of Public Health Sciences University of Sk&#246vde Sk&#246vde Sweden

Introduction: The use of foods containing high levels of sugar is increasing all the time. This is a risk factor for increased incidence of type 2 diabetes. There are few studies that have investigated the availability of low-sugar müsli products in grocery stores. Purpose: The study aims to identify which types of müsli contain high respectively low levels of sugar, and which brands are involved. Methods: The material consists of both qualitative interviews and observations from five grocery stores: City Gross, Hemköp, Ica Maxi, Stora Coop and Willy’s in Helsingborg, Sweden. The qualitative interviews had a semi-structured character and were recorded. The interviews took approx. 20 minutes and a textual analysis was conducted of the results. Data from observation was analyzed based on brand, nutritional composition and flavors, and also, where low sugar products were placed on store shelves. Results: The grocery stores provided together brands from AXA, Coop, Finax, Frebaco, Garant, ICA, Risenta, Saltå Kvarn och Urtekram, in total 24 müsli products. Of these products, 19 were high in sugar. The observation reveals that müsli products with high sugar content (17 - 29 g per 100 g müsli) are more prominently displayed than those with low sugar content. From the interviews with the store managers, it became clear that it would be valuable to highlight healthy müsli products on the shelves. However, central bureaucracy puts obstacles to such measures. Discussion: The study emphasizes the need for increased visibility of low-sugar products and proposes solutions such as negotiating with responsible person at the head office in Stockholm. Several reviews have shown that if the grocery store raises the prices of unhealthy food, the consumer is willing to purchase healthier müsli and other products. Conclusion: This study shows the need for grocery stores to upgrade healthy müsli products along with advertising to be able to influence customer’s shopping habits. Also, furth

关键词： Type 2 Diabetes High Sugar Content in Müsli Difficulty Making Healthy Choices Central Food Bureaucracy