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Mathematical modelling of ball and plate system with experimental and correlation function-based model validation

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Control Theory and Technology 2024年第2期22卷 326-341页

作者： T.r.Dil Kumar S.j.Mija Department of Electrical Engineering National Institute of Technology CalicutKozhikode673601KeralaIndia

The ball and plate system is an inherently nonlinear under actuated benchmark system used for validating the performance of various control schemes. A mathematical model depicting the dynamics close to that of the system is very much required for such a test bed. In this correspondence, the complete nonlinear model, a simplified nonlinear model, and a linearized model of the ball and plate system are developed. The system comprises a ball and plate mechanism and a rotary servo unit. The ball and plate mechanism is modelled using the Euler–Lagrange method, whereas the rotary servo subsystem is modelled from the first principles. The nonlinear model of the combined system is developed by including the dynamics of the servo motor with gear and rolling resistance between the ball and the plate. The simplified nonlinear model of the system is obtained with suitable assumptions. The model is linearized around the operating point using the jacobian. The validity of the developed models is investigated through correlation function analysis. The open-loop response of the three models, viz., nonlinear, simplified nonlinear, and linearized models, is analyzed in the MATLAB/Simulink platform. Since the open-loop system is unstable, the experimental validation of the model is performed with a double-loop PSo (particle swarm optimization) PID control scheme.

关键词： Ball and plate system Correlation function Model validation Particle swarm optimization(PSo) PSo PID controller

Associations between physical activity levels and ATPase inhibitory factor 1 concentrations in older adults

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journal of Sport and Health Science 2024年第3期13卷 409-418页

作者： jérémy raffin Yves rolland Annelise Genoux Guillaume Combes Mikael Croyal Bertrand Perret Sophie Guyonnet Bruno Vellas Laurent o.Martinez Philipe de Souto Barreto for the MAPT/DSA Group Institut du Vieillissement Gérontopôle de ToulouseCentre Hospitalo-Universitaire de ToulouseToulouse 31000France Centre d'Epidémiologie et de recherche en Santédes Populations UnitéMixte de Recherche 1295Institut National de la Santéet de la Recherche MédicaleUniversitéToulouse-III-Paul-SabatierToulouse 31000France LimitAging Team Institut des Maladies Métaboliques et CardiovasculairesUnitéMixte de Recherche 1297Institut National de la Santéet de la Recherche MédicaleUniversitéToulouse III-Paul SabatierToulouse 31432France Service de Biochimie Pôle de biologieHôpital de PurpanCentre Hospitalo-Universitaire de ToulouseToulouse 31300France L'Institut du Thorax Institut National de la Santéet de la Recherche MédicaleCentre National de la Recherche ScientifiqueCentre Hospitalo-Universitaire de NantesNantes UniversitéNantes 44000France BioCore US16Structure Fédérative de Recherche BonamyInstitut National de la Santéet de la Recherche MédicaleCentre National de la Recherche ScientifiqueCentre Hospitalo-Universitaire de NantesNantes UniversitéNantes 44000France Plate-forme de spectrométrie de masse Centre de Recherche en Nutrition HumaineOuestNantes 44000France 不详

Background:Adenosine triphosphatase inhibitory factor 1(IF1)is a key protein involved in energy ***1 has been linked to various agerelated diseases,although its relationship with physical activity(PA)remains ***,the apolipoprotein A-I(apoA-I),a PA-modulated lipoprotein,could play a role in this relationship because it shares a binding site with IF1 on the cell-surface ATP *** examined here the associations between chronic PA and plasma IF1 concentrations among older adults,and we investigated whether apoA-I mediated these ***:In the present work,1096 healthy adults(63.8%females)aged 70 years and over who were involved in the Multidomain Alzheimer Prevention Trial study were ***1 plasma concentrations(square root of ng/mL)were measured at the 1-year visit of the Multidomain Alzheimer Prevention Trial,while PA levels(square root of metabolic equivalent task min/week)were assessed using questionnaires administered each year from baseline to the 3-year *** linear regressions were performed to investigate the associations between the first-year mean PA levels and IF1 *** analyses were conducted to examine whether apoA-I mediated these *** linear regressions were carried out to investigate whether the 1-year visit IF1 concentrations predicted subsequent changes in ***:Multiple linear regressions indicated that first-year mean PA levels were positively associated with IF1 concentrations(B=0.021;SE=0.010;p=0.043).Mediation analyses revealed that about 37.7%of this relationship was mediated by apoA-I(B_(ab)=0.008;SE=0.004;p=0.023).Longitudinal investigations demonstrated that higher concentrations of IF1 at the 1-year visit predicted a faster decline in PA levels over the subsequent 2 years(time×IF1:B=0.148;SE=0.066;p=0.025).Conclusion:This study demonstrates that regular PA is associated with plasma IF1 concentrations,and it suggests that apoA-I partly med

关键词： Aging Apolipoprotein Bioenergetics Exerkine Mitochondria

Wood anatomical acclimation in the endemic genus Polylepis in Peruvian Andean forests

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journal of Mountain Science 2024年第9期21卷 2986-3000页

作者： Anthony GUErrA Fressia N.AMES-MArTÍNEZ Ernesto C.roDrÍguez-rAMÍrEZ Postgraduate Programme in Agronomy/Plant Physiology Department of Biology-Institute of Natural Sciences Federal University of LavrasLavras 37203-202Minas Gerais 30000-31999Brazil Laboratory of Biotechnology and Molecular Biology Continental UniversitySan Antonio UrbanizationHuancayo 12000Peru Ecology and Biodiversity research Programme ANDINUS AssociationMiguel Grau Street 370Huancayo 12000Peru Dendrochronology Laboratory Continental UniversitySan Carlos Avenue 1980Huancayo 12000Peru

Polylepis(Queñua)is a dominant woody plant genus in Andean Puna forests that occurs in a wide range of montane habitats and is ecologically diverse in endemism,which may be particularly threatened by climate *** anatomical traits are essential for understanding how plants adjust their ecophysiological requirements and maximize their resilience,resistance,and recovery to extreme *** the effects of extreme climatic conditions in high altitude ecosystems have been studied extensively,our knowledge is relatively limited to quantitative differences in the main xylem *** address this gap,we assessed the acclimation of wood anatomical traits in six Peruvian Andean Polylepis species with different water availability(semi-dry with high moisture and semiarid with dry winters).We selected hydraulic diameter,vessel density,vessel grouping index,solitary vessel index,vulnerability index,mesomorphy index,vessel element length,fiber length,fiber wall thickness,fiber lumen diameter,and total fiber diameter that can provide relevant eco-wood anatomical acclimation to hydric *** performed multivariate analysis to determine the leading dimensions of covariation among Polylepis species and climatic *** wood anatomical traits(vessel grouping index,vulnerability index,and fiber wall thickness)were dissimilar between xeric-and mesic-Polyelpis *** study demonstrates that wood anatomical traits in Peruvian Andean Polylepis species provides high-resolution and long-term eco-wood anatomical signals on how climate oscillations drive the acclimation processes of fiber and vessel *** findings underscore the significance of xylem hydraulic adjustment to various hydrological environments in Andean puna *** evaluating the effects of drought on wood anatomical characteristics and ecological function,we demonstrate the capacity of tree species to adapt and endure climate-related changes,thereby emphasizing their resilience and ada

关键词： Carlquist indices Climatic resilience Vessel traits Fiber Functional trait Hydric stress

Learning to bag with a simulation‐free reinforcement learning framework for robots

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IET Cyber-Systems and robotics 2024年第2期6卷 52-66页

作者： francisco Munguia-Galeano jihong Zhu juan David Hernández Ze ji Cooper Group University of LiverpoolLiverpoolUK School of Physics Engineering and Technology University of YorkYorkUK School of Computer Science and Informatics Cardiff UniversityCardiffUK School of Engineering Cardiff UniversityCardiffUK

Bagging is an essential skill that humans perform in their daily ***,deformable objects,such as bags,are complex for robots to manipulate.A learning-based framework that enables robots to learn bagging is *** novelty of this framework is its ability to learn and perform bagging without relying on *** learning process is accomplished through a reinforcement learning(rL)algorithm introduced and designed to find the best grasping points of the bag based on a set of compact state *** framework utilises a set of primitive actions and represents the task in five *** our experiments,the framework reached 60% and 80% success rates after around 3 h of training in the real world when starting the bagging task from folded and unfolded states,***,the authors test the trained rL model with eight more bags of different sizes to evaluate its generalisability.

关键词： reinforcement learning robot learning robotics

Polyelectrolyte Complexes between Hyperbranched and Linear Polysaccharides: Fucoidan/Chitosan

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Chinese journal of Polymer Science 2024年第4期42卷 468-479页

作者： Ekaterina r.Gasilova Daria N.Poshina Aleksandra o.Sitnikova Natalia N.Saprykina Yury A.Skorik Institute of Macromolecular Compounds of the russian Academy of Sciences Bolshoi VO 31St.Petersburg199004Russian Federation

Polyelectrolyte complexes(PECs)of hyperbranched(HB)and linear polysaccharides are promising as more effective encapsulation agents compared to PECs formed by linear *** investigated the PECs between the HB anionic polysaccharide fucoidan(FUC)and the cationic linear polysaccharide chitosan(CS).The FUC had a molecular weight(MW)of 30×*** PECs were prepared in three solvents(water,0.01 and 0.1 mol/L acetic acid)with CS of MW of 15,110 and 170 kDa,and deacetylation degrees(DDA)of 70%and 97%.The structures of the PECs and the initial FUC were investigated by multi-angle static and dynamic light *** the FUC contained 18 wt%of—oSo3 groups and 5 wt%of uronic acid units,it was a“strong-weak”copolyanion,so the HB macromolecules of the FUC formed nanogel particles in 0.1 mol/L AcoH and open branched structures in water,as confirmed by the Kratky *** mixing the solutions of original components,the PEC structures underwent an equilibration period,the duration of which increased with the MW of *** the charge stoichiometry was approached,the PECs shrank;the fractal dimension approached unity,indicating the side-by-side packing of adjacent FUC branches with the help of *** aggregation in the vicinity of the charge compensation was hardly observed,as it occurred in a very narrow *** PEC content at theζ-potential inversion depended on solvents’pH and the DDA of *** the extreme case of core-shell PECs in 0.1 mol/L AcoH,obtained by mixing FUC nanogels with the solutions of high MW CS of 97%DDA,the protruding tails of CS formed a positively charged shell in the whole range of FUC content(10 wt%ron microscopy and atomic force microscopy images of dried samples were discussed in relation to the light scattering results.

关键词： Polyelectrolyte complexes Chitosan Hyperbranched fucoidan Light scattering

Back-contact configuration energizes perovskite photovoltaic modules

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Nano research Energy 2024年第2期3卷 7-11页

作者： Xiaoyu Yang Yongguang tu Fengjun Ye Zheng Bao State Key Laboratory for Artificial Microstructure and Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871China Frontiers Science Center for Flexible Electronics(FSCFE) Xi’an Institute of Flexible Electronics(IFE)&Xi’an Institute of Biomedical Materials and Engineering(IBME)Northwestern Polytechnical University Xi’anShaanxi 710072China Beijing Solarverse optoelectronic Technology Co. Ltd.Beijing 100176China

In this viewpoint,recent hot topics in the photovoltaic community,interdigitated back contact(IBC)cells,are systematically reviewed from the view of device *** categories of IBC designs on the most popular perovskite solar cells(PSCs)were discussed,and a planar back-contact perovskite module was first *** device configuration,fabrication methods,working mechanism,optimization strategies,and future development directions of this novel PSC module were put forward to show its superiorities in the module performance,processing difficulty,and extensible functionality among present perovskite modules,presenting promising potential to improve the competitiveness of perovskite technology in the photovoltaic market.

关键词： perovskite solar cell back-contact photovoltaic technology device configuration

Different mechanisms underlie similar species-area relationships in two tropical archipelagoes

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Plant Diversity 2024年第2期46卷 238-246页

作者： Shengchun Li Tieyao tu Shaopeng Li Xian Yang Yong Zheng Liang-Dong Guo Dianxiang Zhang Lin jiang Key Laboratory of Plant resources Conservation and Sustainable Utilization South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China ECNU-Alberta joint Lab for Biodiversity Study Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China School of Biological Sciences Georgia Institute of TechnologyAtlantaGA 30332USA jiangxi Academy of forestry Nanchang 330032China Institute of Eco-Chongming(IEC) Shanghai 202162China State Key Laboratory of Biocontrol School of EcologySun Yat-sen UniversityGuangzhou 510275China School of Geographical Sciences Fujian Normal UniversityFuzhou 350007China State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

Despite much research in the field of island biogeography,mechanisms regulating insular diversity remain ***,we aim to explore mechanisms underlying plant species-area relationships in two tropical archipelagoes in the South China *** found positive plant species-area relationships for both coral and continental ***,our results showed that different mechanisms contributed to similar plant species-area relationships between the two *** coral islands,soil nutrients and spatial distance among communities played major roles in shaping plant community structure and species *** contrast,the direct effect of island area,and to a lesser extent,soil nutrients determined plant species richness on continental ***,increasing soil nutrients availability(N,P,K)had opposite effects on plant diversity between the two *** summary,the habitat quality effect and dispersal limitation are important for regulating plant diversity on coral islands,whereas the passive sampling effect,and to a lesser extent,the habitat quality effect are important for regulating plant diversity on continental *** generally,our findings indicate that island plant species-area relationships are outcomes of the interplay of both niche and neutral processes,but the driving mechanisms behind these relationships depends on the type of islands.

关键词： Coral and continental islands Plant diversity Soil nutrients Species-area relationships The sampling effect

recent development in degradation mechanisms of proton exchange membrane fuel cells for vehicle applications:problems,progress,and perspectives

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Energy Storage and Saving 2024年第2期3卷 106-152页

作者： Zikuo Liu Shanshan Cai Zhengkai tu Siew Hwa Chan School of Energy and Power Engineering Huazhong University of Science and TechnologyWuhan430074China Energy research Institute Nanyang Technological University637553Singapore

Due to its zero emissions,high efficiency and low noise,proton exchange membrane fuel cell(PEMFC)is full of potential for the application of vehicle power ***,its lifespan and durability remain multiple obstacles to be solved before widespread *** exposure to non-rated operating conditions could considerably accelerate the degradation of the PEMFC in various forms,thus reducing its *** paper first analyzes degradation mechanisms of PEMFCs under typical automotive operating conditions,including idling,startup-shutdown,dynamic loads,and cold *** corresponding accelerated stress testing methods are also ***,as the impurities existed in the reaction gas source and generated from the degradation of the PEMFC itself may occur under all automotive conditions,the degradation mechanisms caused by impurity contamination are classified and reviewed in *** that,the techniques proposed by researchers to enhance the durability of PEMFCs are presented from four aspects:membrane electrode assembly materials,bipolar plates and flow fields design,stack assembly,and cell control *** challenges in the field and the prospects for the future are summarized and analyzed at the *** aim of this work is to provide guidelines for improving the durability of PEMFCs in vehicle applications.

关键词： Proton exchange membrane fuel cell Vehicle Automotive operating conditions Degradation Durability

rapid Simultaneous Determination of four Ganoderic Acids in Ganoderma(Chinese Name:Lingzhi)by Direct Infusion-Multiple reaction Monitoring Cubed

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journal of Analysis and Testing 2024年第1期8卷 52-62页

作者： Nian Wu Bo Peng Ting Li Pengfei tu Shengpeng Wang Bo Li Wenjing Liu Yuelin Song Modern research Center for Traditional Chinese Medicine Beijing Research Institute of Chinese MedicineBeijing University of Chinese MedicineBeijing 100029China Amway(China)Botanical research Center Wuxi 214011China State Key Laboratory of Quality research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipa 999078China Amway(Shanghai)Innovation&Science Co. LtdShanghai 201508China School of Pharmacy Henan University of Chinese MedicineZhengzhou 450046China

Attributing to the rapid demand expansion for the edible medicinal materials in the market,the limited throughput of highperformance liquid chromatography-multiple reaction monitoring(HPLC-MrM)cannot fully address the measurement workload for a huge number of testing ***,it is urgent to pursue more efficient approaches for the quality *** of the greater selectivity of MrM cubed(MrM^(3))over MrM,there might be a chance to omit the time-intensive LC *** current study,we attempted to develop a direct infusion(DI)-MrM^(3) program,and the applicability was thereafter assessed through simultaneous determination of four ganoderic acids(GAs)in one of the most famous tonic herbal medicines namely Ganoderma(Chinese name:Lingzhi).Primary parameters such as Q1>Q3>QLIT ion transitions,collision energy(CE),and excitation energy were optimized by programming online energy-resolved mass spectrometry with authentic compounds.A single DI-MrM measurement merely costed four minutes,and in spite of the wide occurrences of isomers,satisfactory selectivity was *** validation assays demonstrated the method to be sensitive,precise,accurate,and *** quantitative results from DI-MrM^(3) were also justified by conducting LC-MrM measurements in *** differences occurred for the content patterns between the two original sources namely Ganoderma lucidum and ***,and,moreover,either cultivar or harvest time showed dramatical influence on the quantitative features of the four targeted *** importantly,DI-MrM3 is a meaningful analytical option for rapid quantitative analysis of herbal medicines,because of the comparable reliability,nonetheless,less consumptions of both measurement time and solvent,compared with LC-MrM.

关键词： Direct infusion Multiple reaction monitoring cubed High-throughput quantitative analysis Ganoderic acids Ganoderma