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Changes in physical activity and sleep following the COVID-19 pandemic on a university campus:Perception versus reality

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Sports Medicine and Health Science 2024年第3期6卷 246-251页

作者： Bryce t.Daniels Samantha Robinson ivan Vargas Jamie I.Baum Erin K.Howie University of Arkansas FayettevilleARUnited States Rush University Medical Center ChicagoIllinoisUnited States1 University of Arkansas System Division of Agriculture FayettevilleARUnited States

It has been hypothesized that key lifestyle behaviors of physical activity and sleep worsened in response to the Coronavirus disease(COVID-19)***,there have been inconsistencies in findings of changes in these key lifestyle behaviors across populations likely due to the wide variety of assessment *** purpose of the study was to compare physical activity and sleep before and after the COVID-19 pandemic using accelerometers and self-reported behaviors.A longitudinal follow-up was conducted on students,faculty,and staff at a university campus in the United *** the periods before March 2020(covering the academic years of 2018–2019 or 2019–2020)and again in April–June 2021,participants completed surveys to evaluate their physical activity and sleep behaviors and wore an accelerometer.A total of 44 participants completed the survey at both timepoints and 32 completed accelerometer assessment at both ***-seven percent of participants reported a perceived decline in physical activity,while 30%reported a worsening in *** selfreported data,overall physical activity did not change,but there was a decrease in active transport(ptic physical activity(p?0.012).Sleep quality decreased as evidenced by an increase in Pittsburgh Sleep Quality Index scores(p?0.045).there were no changes in accelerometer measured physical activity or *** were no changes in physical or mental *** perceptions of physical activity declined from prior to the COVID-19 pandemic,there were no changes in device-measured physical activity,and changes in self-reported physical activity differed by domain.

关键词： Movement Longitudinal Measurement

不锈钢和CFRP混合配筋预应力混凝土梁的延性和变形性能

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工程力学 2005年第3期22卷 190-197页

作者：方志 t.ivan Campbell 湖南大学土木工程学院湖南长沙410082 Department of Civil Engineering Queen’s University Kingston Ontario Canada K7L 3N6

由于FRP(fiber-reinforcedpolymer/Plastics)材料直到拉断还表现出线弹性的力学性能,使得采用FRP配筋的混凝土结构延性较差,且已成为这类结构应用中人们所关注的一个主要问题。研究了不锈钢和CFRP(Carbonfiber-reinforcedpolymer/Plastics)混合配筋部分粘结、部分预应力混凝土梁的延性和变形特性。分析时假定这类梁的截面在加载过程中具有3折线的弯矩-曲率关系,而在卸载过程中截面的弯矩-曲率关系假定为线性,据此提出了这类梁受力全过程的非线性分析方法,并以试验结果验证了其适用性。基于能量耗散的观点引入了反映这类梁延性特性的延性指标,并利用所提分析方法对这类梁的延性进行了参数分析。分析结果表明:增加混凝土极限压应变和预应力束的无粘结部分长度可以有效地增加这类梁的变形性能,但对延性的增加却很有限,而且这两个参数对梁延性和变形性能的影响程度还强烈依赖于梁的破坏形态。

关键词：混凝土预应力不锈钢碳纤维(CFRP) 梁延性

Emerging and multifaceted potential contributions of polyphenols in the management of type 2 diabetes mellitus

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World Journal of Diabetes 2024年第2期15卷 154-169页

作者： Ileana González Cristian Lindner ivan Schneider Erik Diaz Miguel Angel Morales Armando Rojas Biomedical Research Laboratories Faculty of MedicineCatholic University of MauleTalca 34600000Chile Department of Radiology Faculty of MedicineUniversity of ConcepciónConcepción 4030000Chile Centre of Primary Attention South Metropolitan Health ServiceSantiago 3830000Chile Faculty of Medicine Catholic University of MauleTalca 3460000Chile Molecular and Clinical Pharmacology Program Institute of Biomedical SciencesUniversity of ChileSantiago 8320000Chile

type 2 diabetes mellitus(t2DM)is recognized as a serious public health concern with a considerable impact on human life,long-term health expenditures,and substantial health *** this context,the use of dietary polyphenols to prevent and manage t2DM is widely *** dietary compounds exert their beneficial effects through several actions,including the protection of pancreatic islet β-cell,the antioxidant capacities of these molecules,their effects on insulin secretion and actions,the regulation of intestinal microbiota,and their contribution to ameliorate diabetic complications,particularly those of vascular *** the present review,we intend to highlight these multifaceted actions and the molecular mechanisms by which these plant-derived secondary metabolites exert their beneficial effects on type 2 diabetes patients.

关键词： Polyphenols Antioxidants Oxidative stress type 2 diabetes mellitus Health benefits

Polariton lasing in Mie-resonant perovskite nanocavity

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Opto-Electronic Advances 2024年第4期7卷 27-42页

作者： Mikhail A.Masharin Daria Khmelevskaia Valeriy I.Kondratiev Daria I.Markina Anton D.Utyushev Dmitriy M.Dolgintsev Alexey D.Dmitriev Vanik A.Shahnazaryan Anatoly P.Pushkarev Furkan Isik ivan V.Iorsh ivan A.Shelykh Hilmi V.Demir Anton K.Samusev Sergey V.Makarov UNAM-Institute of Materials Science and Nanotechnology National Nanotechnology Research CenterDepartment of Electrical and Electronics EngineeringDepartment of PhysicsBilkent UniversityAnkara 06800Turkey ItMO University School of Physics and EngineeringSt.Petersburg 197101Russia Abrikosov Center for theoretical Physics MIPTDolgoprudnyiMoscow Region 141701Russia LUMINOUS!Center of Excellence for Semiconductor Lighting and Displays School of Electrical and Electronic EngineeringSchool of Physical and Mathematical SciencesSchool of Materials Science and EngineeringNanyang Technological UniversitySingapore 639798Singapore Department of Physics Engineering Physics and AstronomyQueen’s UniversityKingstonOntario K7L 3N6Canada Science Institute University of IcelandDunhagi 3IS-107ReykjavikIceland Experimentelle Physik 2 Technische Universität DortmundDortmund 44227Germany Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao 266000China

Deeply subwavelength lasers(or nanolasers)are highly demanded for compact on-chip bioimaging and sensing at the *** of the main obstacles for the development of single-particle nanolasers with all three dimensions shorter than the emitting wavelength in the visible range is the high lasing thresholds and the resulting *** we ex-ploit exciton-polariton condensation and mirror-image Mie modes in a cuboid CsPbBr3 nanoparticle to achieve coherent emission at the visible wavelength of around 0.53μm from its ultra-small(≈0.007μm3 or≈λ3/20)semiconductor *** polaritonic nature of the emission from the nanocavity localized in all three dimensions is proven by direct com-parison with corresponding one-dimensional and two-dimensional waveguiding systems with similar material *** a deeply subwavelength nanolaser is enabled not only by the high values for exciton binding energy(≈35 meV),re-fractive index(>2.5 at low temperature),and luminescence quantum yield of CsPbBr3,but also by the optimization of po-laritons condensation on the Mie resonances with quality factors improved by the metallic ***,the key parameters for optimal lasing conditions are intermode free spectral range and phonons spectrum in CsPbBr3,which govern polaritons condensation *** chemically synthesized colloidal CsPbBr3 nanolasers can be potentially de-posited on arbitrary surfaces,which makes them a versatile tool for integration with various on-chip systems.

关键词： nanolaser perovskite polariton Mie resonance exciton-polariton

Effect of special types of bread with select herbal components on postprandial glucose levels in diabetic patients

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World Journal of Diabetes 2024年第4期15卷 664-674页

作者： Drasko M Gostiljac Srdjan S Popovic Vesna Dimitrijevic-Sreckovic Sasa M Ilic Jelena A Jevtovic Dragan M Nikolic ivan A Soldatovic Clinic for Endocrinology Diabetes and Metabolic DiseasesUniversity Clinical Centre of SerbiaBelgrade 11000Serbia Faculty of Medicine University of BelgradeBelgrade 11000Serbia Clinic for Gastroenterology and Hepatology University Clinical Centre of SerbiaBelgrade 11000Serbia Clinic for Endocrinology Diabetes and Metabolic Diseases-Laboratory for Human Pancreatic Islets CultureUniversity Clinical Centre of SerbiaBelgrade 11000Serbia

BACKGROUND Nutrition recommendations in patients with type 2 diabetes mellitus(t2DM)are to consume rye or integral bread instead of white bread.A positive effect on glucoregulation has been achieved by enriching food with various biologically active substances of herbal origin,so we formulated an herbal mixture that can be used as a supplement for a special type of bread(StB)to achieve better effects on postprandial glucose and insulin levels in patients with *** to compare organoleptic characteristics and effects of two types of bread on postprandial glucose and insulin levels in t2DM *** this trial included 97 patients with t2DM.A parallel group of 16 healthy subjects was also *** participants were given 50 g of rye bread and the same amount of a StB with an herbal mixture on 2 consecutive *** blood glucose and insulin levels were compared at the 30^(th),60^(th),90^(th) and 120th min.A questionnaire was used for subjective estimation of the organoleptic and satiety features of the two types of *** Compared to patients who consumed rye bread,significantly lower postprandial blood glucose and insulin concentrations were found in t2DM patients who consumed *** relevant differences were found among the healthy *** estimated organoleptic and satiety characteristics are better for StB than for rye *** StB have better effects than rye bread on postprandial glucoregulation in t2DM *** estimated organoleptic and satiety characteristics are better for StB than for rye ***,StB can be recommended for nutrition in t2DM patients.

关键词： Special types of bread Postprandial glucoregulation Insulin Nutrition type 2 diabetes mellitus

Elevated brain temperature under severe heat exposure impairs cortical motor activity and executive function

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Journal of Sport and Health Science 2024年第2期13卷 233-244页

作者： Xiang Ren tan Mary C.Stephenson Sharifah Badriyah Alhadad Kelvin W.Z.Loh tuck Wah Soong Jason K.W.Lee ivan C.C.Low Health and Social Sciences Singapore Institute of TechnologySingapore 138683Singapore Human Potential translational Research Programme Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117597Singapore Centre for translational Magnetic Resonance Research Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117549Singapore Department of Physiology Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117593Singapore Heat Resilience and Performance Centre Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117510Singapore N.1 Institute for Health National University of SingaporeSingapore 117456Singapore Campus for Research Excellence and technological Enterprise(CREAtE) Singapore 138602Singapore

Background:Excessive heat exposure can lead to hyperthermia in humans,which impairs physical performance and disrupts cognitive *** heat is a known physiological stressor,it is unclear how severe heat stress affects brain physiology and ***:Eleven healthy participants were subjected to heat stress from prolonged exercise or warm water immersion until their rectal temperatures(t_(re))attained 39.5℃,inducing exertional or passive hyperthermia,*** a separate trial,blended ice was ingested before and during exercise as a cooling *** were compared to a control condition with seated rest(normothermic).Brain temperature(t_(br)),cerebral perfusion,and task-based brain activity were assessed using magnetic resonance imaging ***:t_(br)in motor cortex was found to be tightly regulated at rest(37.3℃±0.4℃(mean±SD))despite fluctuations in t_(re).With the development of hyperthermia,t_(br)increases and dovetails with the rising t_(re).Bilateral motor cortical activity was suppressed during high-intensity plantarflexion tasks,implying a reduced central motor drive in hyperthermic participants(t_(re)=38.5℃±0.1℃).Global gray matter perfusion and regional perfusion in sensorimotor cortex were reduced with passive *** function was poorer under a passive hyperthermic state,and this could relate to compromised visual processing as indicated by the reduced activation of left lateral-occipital ***,ingestion of blended ice before and during exercise alleviated the rise in both t_(re)and t_(bc)and mitigated heat-related neural ***:Severe heat exposure elevates t_(br),disrupts motor cortical activity and executive function,and this can lead to impairment of physical and cognitive performance.

关键词： Brain functional activity Cognition Heat stress Hyperthermia Motor function

身份融合对农民工就业的影响——基于倾向得分匹配的研究（英文）

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中国农业大学学报 2018年第7期23卷 176-191页

作者：卢海阳 KANDILOV t.ivan 福建农林大学公共管理学院福州350002 北卡罗莱纳州立大学农业与资源经济系美国罗利27606

身份融合是理解农民工经济行为的重要概念。基于2013年浙江省的农民工调研数据,本研究探讨了身份融合对农民工就业的影响。为了解决可能存在的自选择问题,采用倾向得分匹配法进行实证分析。结果表明:身份融合对农民工的劳动参与有显著影... 详细信息

身份融合是理解农民工经济行为的重要概念。基于2013年浙江省的农民工调研数据,本研究探讨了身份融合对农民工就业的影响。为了解决可能存在的自选择问题,采用倾向得分匹配法进行实证分析。结果表明:身份融合对农民工的劳动参与有显著影响,身份融合对农民工自我雇佣和工作强度的影响并不显著;身份融合对农民工就业的影响存在明显的代际差异、性别差异以及户籍地差异。本研究获得的政策启示在于:促进农民工的城市融入有利于稳定他们的就业预期,实现劳动供给的可持续发展,对中国经济的发展具有重要作用。

关键词：就业身份融合倾向得分匹配农民工

Influence of Statins and Fibrates Drugs on Bone Health and Regeneration

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Journal of Biomaterials and Nanobiotechnology 2024年第1期15卷 1-24页

作者： Octavio Santiago ivan Nadir Camal Ruggieri Marina Ribeiro Paulini Valéria Paula Sassoli Fazan João Paulo Mardegan Issa Sara Feldman LABOAtEM Laboratory of Bone Biology and Tissue Engineering School of Medicine Rosario National University Ros&#225rio Argentina School of Dentistry of Ribeirã o Preto University of S&#227o Paulo (FORP/USP) Ribeir&#227o Preto S&#227o Paulo Brazil School of Medicine of Ribeirã o Preto University of S&#227o Paulo (FMRP/USP) Ribeir&#227o Preto S&#227o Paulo Brazil

In the medical and dental field, the importance and need for the study of materials and drugs for use as bone grafts or regeneration in injured areas due to the presence of fractures, infections or tumors that cause extensive loss of bone tissue is observed. Bone is a specialized, vascularized and dynamic connective tissue that changes throughout the life of the organism. When injured, it has a unique ability to regenerate and repair without the presence of scars, but in some situations, due to the size of the defect, the bone tissue does not regenerate completely. thus, due to its importance, there is a great development in therapeutic approaches for the treatment of bone defects through studies that include autografts, allografts and artificial materials used alone or in association with bone grafts. Pharmaceuticals composed of biomaterials and osteogenic active substances have been extensively studied because they provide potential for tissue regeneration and new strategies for the treatment of bone defects. Statins work as specific inhibitors of 3-hydroxy-3-methyl-glutaryl coenzyme A reductase (HMG-CoAreductase). they represent efficient drugs in lowering cholesterol, as they reduce platelet aggregation and thrombus deposition;in addition, they promote angiogenesis, reduce the β-amyloid peptide related to Alzheimer’s disease and suppress the activation of t lymphocytes. Furthermore, these substances have been used in the treatment of hypercholesterolemia and coronary artery disease. By inhibiting HMG-CoAreductase, statins not only inhibit cholesterol synthesis, but also exhibit several other beneficial pleiotropic effects. therefore, there has been increasing interest in researching the effects of statins, including Simvastatin, on bone and osteometabolic diseases. However, statins in high doses cause inflammation in bone defects and inhibit osteoblastic differentiation, negatively contributing to bone repair. thus, different types of studies with different conc

关键词： Bone Statins Rosuvastatin Sinvastatin Fibrates Fenofibrate Bone Regeneration

Hordedane diterpenoid phytoalexins restrict Fusarium graminearum infection but enhance Bipolaris sorokiniana colonization of barley roots

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Molecular Plant 2024年第8期17卷 1307-1327页

作者： Yaming Liu Dario Esposto Lisa K.Mahdi Andrea Porzel Pauline Stark Hidayat Hussain Anja Scherr-Henning Simon Isfort Ulschan.Bathe ivan F.Acosta Alga Zuccaro Gerd U.Balcke Alain tissier Department of Cell and Metabolic Biology Leibniz Institute of Plant BiochemistryHalleGermany Institute for Plant Sciences Cluster of Excellence on Plant Sciences(CEPLAS)Cologne BiocenterUniversity of CologneCologneGermany Department of Bioorganic Chemistry Leibniz Institute of Plant BiochemistryHalleGermany Max Planck Institute for Plant Breeding Research CologneGermany Horticultural Sciences University of FloridaGainesvilleFLUSA.

Plant immunity is a multilayered process that includes recognition of patterns or effectors from pathogens to elicit defense *** include the induction of a cocktail of defense metabolites that typically restrict pathogen ***,we investigate the interaction between barley roots and the fungal pathogens Bipolaris sorokiniana(Bs)and Fusarium graminearum(Fg)at the metabolite *** identify hordedanes,a previously undescribed set of labdane-related diterpenoids with antimicrobial properties,as critical players in these *** of barley roots by Bs and Fg elicits hordedane synthesis from a 60o-kb gene *** reconstruction of the biosynthesis pathway in yeast and Nicotiana benthamiana produced several hordedanes,including one of the most functionally decorated products 19-β-hydroxy-hordetrienoic acid(19-OH-HtA).Barley mutants in the diterpene synthase genes of this cluster are unable to produce hordedanes but,unexpectedly,show reduced Bs *** contrast,colonization by Fusarium graminearum,another fungal pathogen of barley and wheat,is 4-fold higher in the mutants completely lacking ***,19-OH-HtA enhances both germination and growth of Bs,whereas it inhibits other pathogenic fungi,including *** of microscopy and transcriptomics data suggest that hordedanes delay the necrotrophic phase of *** together,these results show that adapted pathogens such as Bs can subvert plant metabolic defenses to facilitate root colonization.

关键词： barley Hordeum vulgare diterpenoid phytoalexins gene cluster pathogenic fungi Bipolaris sorokininiana Fusarium graminearum