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Theoretical and experimental study of a bi-stable piezoelectric energy harvester under hybrid galloping and band-limited random excitations

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 461-478页

作者： Haitao LI Tianyu ZHENG Weiyang QIN Ruilan TIAN Hu DING J.c.JI Liqun cHEN Department of Engineering Mechanics North University of ChinaTaiyuan 030051China Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechnoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China School of Mechanical and Mechatronic Engineering University of Technology SydneyNew South Wales 2007Australia

In the practical environment,it is very common for the simultaneous occurrence of base excitation and *** the combined energy of vibration and wind with a single energy harvesting structure is *** this purpose,the effects of the wind speed and random excitation level are investigated with the stochastic averaging method(SAM)based on the energy *** results of the analytical prediction are verified with the Monte-carlo method(McM).The numerical simulation shows that the introduction of wind can reduce the critical excitation level for triggering an inter-well jump and make a bi-stable energy harvester(BEH)realize the performance enhancement for a weak base ***,as the strength of the wind increases to a particular level,the influence of the random base excitation on the dynamic responses is weakened,and the system exhibits a periodic galloping response.A comparison between a BEH and a linear energy harvester(LEH)indicates that the BEH demonstrates inferior performance for high-speed *** experiments are conducted to investigate the validity of the theoretical prediction and numerical *** experimental findings also show that strong random excitation is favorable for the BEH in the range of low wind ***,as the speed of the incoming wind is up to a particular level,the disadvantage of the BEH becomes clear and evident.

关键词： bi-stability inter-well response galloping band-limited random

crystal structure and luminescence dynamics of highly pure LiM(PO_(3))_(3):Eu^(3+)(M=Sr,ca) red phosphors for white light emitting diodes

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Journal of Rare Earths 2024年第8期42卷 1470-1478,I0002页

作者： Payal Khajuria M.Manhas A.K.Bedyal Ankush Vij H.c.Swart Vinay Kumar Department of Physics and Astronomical Sciences Central University of JammuRahy-Suchani.Samba1143J&KIndia Department of Physics School of SciencesCluster University of JammuCanal RoadJammu180001India Department of Physics University of Petroleum and Energy StudiesDehradunUttarakhand248007India Department of Physics University of the Free StateP.O.Box 339BloemfonteinZA 9300South Africa

Highly pure red phosphors LiM(PO_(3))_(3):Eu^(3+)(M=Sr,ca) doped with Eu^(3+)(1 mol%) were synthesized via solution combustion method and their crystal structure and luminescence dynamics were studied to explore its suitability in white light emitting *** Rietveld refinement analysis of the powder Xray diffraction patterns reveals that the phosphors belong to the pure triclinic phase of LiSr(PO_(3))_(3) and Lica(PO_(3)) with space group P-1(2).The scanning electron microscopy images showed the agglomerated *** photoluminescence emission spectra under 393 nm show an orange band at 594 nm and a red band at 613 nm ascribed to ^(5)D_(0)→^(7)F_(1).^(5)D_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the ***,the spectroscopic properties such as luminescence behaviour,and Stark splitting were used to examine the symmetry of Eu^(3+)ions in LiM(PO_(3))_(3):Es^(3+)(M=Sr,ca) phosphors in terms of distortion induced upon *** Stark splitting shows that the actual site symmetry for Eu^(3+)ion was estimated to be D_(2) type for both *** photometric properties of Lica(PO_(3))_(3):Eu^(3+)such as commission International de l'Eclairage coordinates(x=0.64,y=0.36) near to the standard one(red),high color purity(95%) and higher brightness reveal that the phosphor has the capability of acting as a red component in n-UV white light emitting diodes.

关键词： Photoluminescence Phosphate WLEDs Stark splitting Rare earths

Are school uniforms associated with gender inequalities in physical activity? A pooled analysis of population-level data from 135 countries/regions

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Journal of Sport and Health Science 2024年第4期13卷 590-598页

作者： Mairead Ryan Luiza I.c.Ricardo Nicole Nathan Riikka Hofmann Esther van Sluijs Medical Research council Epidemiology Unit University of CambridgeCambridge CB20QQUK Faculty of Education University of CambridgeCambridge CB28PQUK Hunter New England Population Health WallsendNSW 2287Australia School of Medicine and Public Health College of HealthMedicine and WellbeingUniversity of NewcastleCallaghanNSW 2308Australia Hunter Medical Research Institute New Lambton HeightsNSW 2305Australia National centre of Implementation Science University of NewcastleCallaghanNSW 2308Australia

Purpose:It is aimed to assess whether school uniforms are associated with population-level gender inequalities in physical activity,and whether associations differ by school level,country/region income,and assessment ***:An ecological study design was *** collected data about global uniform practices using an online *** searched for country/region-level estimates of school-aged youth meeting physical activity guidelines from international surveillance *** selection was conducted in duplicate using a systematic process,and a random sample of all data was checked to ensure extraction and pooling processes were *** calculated absolute and relative gender inequalities in physical activity for each *** regression examined associations between country/region-level uniform practices(binary yes/no exposure variable) and country/region-level gender inequalities in physical activity guideline compliance(absolute and relative inequalities).We investigated moderation by school level,stratified analyses by income group,and repeated primary analyses using device-measured ***:Pooling data from 135 countries/regions(n=1,089,852),we found no association between population-level uniform practices and gender inequalities in physical activity across all ages(absolute:β=-0.2;95% confidence interval(95%cI):-1.7 to 1.3,p=0.74;relative:β=0.1;95%cI:-0.1 to 0.2,p=0.51).Subgroup analysis suggested a positive association in primary school settings(absolute:β=4.3;95%cI:-0.0 to 8.6,p=0.05).Among high-income countries,absolute inequalities were significantly greater in countries/regions with uniform practices(N=37) compared to those without(N=48)(9.1(SD=3.6) vs.7.8 percentage points(SD=4.3)).Repeating analyses using device-measured data(n=32,130;N=24) did not alter our primary *** initial descriptive statistics,we found that in countries/regions where a maj ority of schools(>50%) reportedly use uniforms,there was lower compli

关键词： School policy clothing child Adolescent Accelerometer

Slope stability of reclaimed coal mines through a new water filling index

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 828-839页

作者： Antonios Mikroutsikos Alexandros I.Theocharis Nikolaos c.Koukouzas Ioannis E.Zevgolis chemical Process&Energy Resources Institute Centre for Research&Technology HellasAthensGreece School of Mining and Metallurgical Engineering National Technical University of AthensAthensGreece

A common reclamation practice for closed coal surface mines is filling them with water to form pit *** creation and sustainability of these lakes are significantly affected by the stability of the corresponding *** present study provides a general framework for analyzing the water filling’s effect on slope stability based on a new water filling index,which can indirectly consider the factors affecting the process and efficiently quantify the filling speed’s *** assumptions of the proposed approach are thoroughly discussed,and the range of the water filling index is ***,the safety factor is calculated using the finite element method with the shear strength reduction technique during the filling process for various conditions(soil properties,slope geometry,hydraulic conditions,and water filling speed).Results are presented as normalized stability charts for practical *** the water filling,the stability gradually decreases until the reservoir reaches a critical level of 10%e40%of the total height;it then increases to even more stable conditions than the initial ***,the present analysis allows for the preliminary stability evaluation of a coal mine during the formation of a pit lake and the appropriate quantification of the water filling’s effect.

关键词： Post-coal era Open-pit flooding Stability charts critical level

cannabinoids and endocannabinoids as therapeutics for nervous system disorders:preclinical models and clinical studies

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Neural Regeneration Research 2024年第4期19卷 788-799页

作者： R.Scott Duncan Sean M.Riordan Matthew c.Gernon Peter Koulen Department of Ophthalmology School of MedicineUniversity of Missouri Department of Biomedical Sciences School of MedicineUniversity of Missouri

cannabinoids are lipophilic substances derived from cannabis sativa that can exert a variety of effects in the human *** have been studied in cellular and animal models as well as in human clinical trials for their therapeutic benefits in several human *** of these include central nervous system(cNS)diseases and dysfunctions such as forms of epilepsy,multiple sclerosis,Parkinson’s disease,pain and neuropsychiatric *** addition,the endogenously produced cannabinoid lipids,endocannabinoids,are critical for normal cNS function,and if controlled or modified,may represent an additional therapeutic avenue for cNS *** review discusses in vitro cellular,ex vivo tissue and in vivo animal model studies on cannabinoids and their utility as therapeutics in multiple cNS *** addition,the review provides an overview on the use of cannabinoids in human clinical trials for a variety of cNS *** and endocannabinoids hold promise for use as disease modifiers and therapeutic agents for the prevention or treatment of neurodegenerative diseases and neurological disorders.

关键词： anandamide cannabidiol cannabinoid endocannabinoid epilepsy multiple sclerosis neurodegeneration neuroprotection tetrahydrocannabinol

Adsorption of pharmaceutical pollutants on Zncl_(2)-activated biochar from corn cob:Efficiency,selectivity and mechanism

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Journal of Bioresources and Bioproducts 2024年第1期9卷 58-73页

作者： christian F.Varela L.c.Moreno-Aldana Yazmin Yaneth Agámez-Pertuz Department of chemistry National University of ColombiaAv.Carrera 30 No.45-03BogotáD.C.Colombia Department of Biology and chemistry University of the Llanoskm 12 road to Puerto LópezVillavicencioColombia

The occurrence of pharmaceuticals in water bodies and drinking water poses risks for the envi-ronment and human health,thus it is necessary to study methodologies that allow the efficient removal of these *** this work,corn cob-derived biochar was obtained by Zncl_(2)-activation,and subsequent carbonization at 700℃.The effect of contact time,temperature,pH,and initial concentration on the adsorption capacity of acetaminophen(AcE)and amoxicillin(AMX)was determined through batch *** addition,the kinetics,isotherms,and ther-modynamics parameters were *** activated biochar exhibited a maximum adsorp-tion capacity of 332.08 mg/g for AcE and 175.86 mg/g for *** adsorption kinetics and adsorption isotherm of AcE corresponded to the pseudo-second order and Langmuir model,***,pseudo-first-order kinetics and the Freundlich isotherm model were well-fitted to AMX *** AcE and AMX co-adsorption had a synergistic effect on AMX but an antagonistic effect on AcE removal,achieving a maximum adsorption capacity of 193.51 and 184.58 mg/g,*** the other hand,fixed-bed column experiments showed that the adsorption capacity depends on the influent concentration,and the breakthrough curve fits the Thomas and Yoon-Nelson *** mechanism adsorption studies showed that surface inter-actions(hydrogen bonding formation and n-𝜋interactions)are the main driving forces for the adsorption process,and pore filling is the rate-limiting *** this way,the prepared biochar exhibits a high potential for the adsorption of pharmaceutical compounds from water.

关键词： Biochar Adsorption Acetaminophen Amoxicillin Wastewater treatment

characterization of conception drawing in architecture to face technological mediations

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Frontiers of Architectural Research 2024年第3期13卷 425-438页

作者： Hugo c.Gomez-Tone Javier F.Raposo Grau Departamento de Ideación Gráfica Arquitectónica Universidad Politécnica de MadridMadrid 28040Spain Departamento de Arquitectura Universidad Nacional de San Agustín de ArequipaArequipa 04001Peru

The conception drawing in architecture is that allows to initiate the architectural thinking,visualizing,and discovering the first *** drawing has traditionally been given as an act of linking and collaboration between thought,sight,and the movement of the hands with a *** and recognizing its characteristics will make it possible to deal with any mediation of information *** establish such characteristics,three case studies were carried *** analysis was made of the conception drawings and interviews by the Pritzker Prize laureates:Ando,Hadid and *** condition and four characteristics have been determined:drawing is a phenomenological action that produces haptic drawings;it is an undecided process that originates unformed drawings;it is a fast action that results in small and multiplied drawings;it is a perceptual act that generates redrawn and remarked drawings;and finally,it is an action that seeks to remember to resume the creative process at another moment,which produces rudimentary conventional *** these before any technological mediation will be an important pedagogical contribution that will allow future architects not to alter the cognitive processes that generate the first ideas in the initial moments of the architectural project.

关键词： conception drawing Architectural thinking Graphic ideation concept creativity

Blood metal concentrations and cardiac structure and function in total joint arthroplasty patients

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World Journal of Orthopedics 2024年第8期15卷 773-782页

作者： Peter c Brennan Stephanie M Peterson Thomas J O'Byrne Mariana L Laporta cody c Wyles Paul J Jannetto Garvan c Kane Maria Vassilaki Hilal Maradit Kremers Department of Orthopedic Surgery Mayo ClinicRochesterMN 55905United States Department of Quantitative Health Sciences Mayo ClinicRochesterMN 55905United States Department of Anesthesiology and Perioperative Medicine Mayo ClinicRochesterMN 55905United States Department of Laboratory Medicine and Pathology Mayo ClinicRochesterMN 55905United States Department of cardiovascular Diseases Mayo ClinicRochesterMN 55905United States

BAcKGROUND There is concern regarding potential long-term cardiotoxicity with systemic distribution of metals in total joint arthroplasty(TJA)*** To determine the association of commonly used implant metals with echocardiographic measures in TJA *** The study comprised 110 TJA patients who had a recent history of high chromium,cobalt or titanium *** underwent two-dimensional,three-dimensional,Doppler and speckle-strain transthoracic echocardiography and a blood draw to measure metal *** and sex-adjusted linear and logistic regression models were used to examine the association of metal concentrations(exposure)with echocardiographic measures(outcome).RESULTS Higher cobalt concentrations were associated with increased left ventricular end-diastolic volume(estimate 5.09;95%cI:0.02-10.17)as well as left atrial and right ventricular dilation,particularly in men but no changes in cardiac *** titanium concentrations were associated with a reduction in left ventricle global longitudinal strain(estimate 0.38;95%cI:0.70 to 0.06)and cardiac index(estimate 0.08;95%cI,-0.15 to-0.01).cONcLUSION Elevated cobalt and titanium concentrations may be associated with structural and functional cardiac changes in some *** studies are warranted to better understand the systemic effects of metals in TJA patients.

关键词： Total joint arthroplasty Metal-on-metal cardiotoxicity Heart failure Echocardiography cobalt

Polio eradication surveillance in Sri Lanka,2019-2023

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Asian Pacific Journal of Tropical Medicine 2024年第6期17卷 268-272页

作者： M.A.Y.Fernando N.S.Madarasinghe c.Rangana N.Weerasinghe D.c.U.D.Weligamage J.I.Abeynayake Department of Medical Microbiology and Immunology Faculty of MedicineUniversity of ColomboSri Lanka Department of Virology Medical Research InstituteColombo 08Sri Lanka Medical Research Institute Colombo 08Sri Lanka

Objective:To evaluate the polio laboratory surveillance carried out from January,2019 to May,2023 by the Polio Regional Reference Laboratory,Sri ***:This retrospective study analyzed all stool samples received under the acute flaccid paralysis(AFP)and immunodeficient vaccine-derived poliovirus(VDPV)surveillance at Polio Regional Reference Laboratory,Sri Lanka from January,2019 to May,*** results of the testing methodologies were extracted from the laboratory data system,i.e.,poliovirus virus isolation,intra-typic differentiation/VDPV real time reverse transcriptase polymerase chain reaction(ITD/VDPV rRTPcR)and sequencing,along with the data on timing of reporting results,stool adequacy and *** was analyzed using descriptive ***:A total of 2141 stool samples from 1644 cases were received for AFP surveillance from Sri Lanka(93.61%),Maldives(1.52%),and immunodeficient VDPV(4.86%)*** polioviruses(19/1644,1.15%)and non-polio enteroviruses(73/1644,4.44%)were isolated,while Sabin-like 3 virus was detected in majority(12/19,63.15%)among the poliovirus *** polioviruses or circulating VDPVs were not detected among the *** all years of the study,the non-polio AFP detection rate was>1/100000 in children aged less than 15 years,whereas stool adequacy rate was>80%.All results were reported within 14 days of receipt,ensuring timely reporting as per global ***:The Polio Regional Reference Laboratory,Sri Lanka plays a vital role in maintaining the polio-free status in the country through its robust laboratory surveillance,while adhering to the surveillance ***-detection of wild polioviruses and circulating VDPV during the study period reinforces the polio-free status in the country.

关键词： Poliovirus Polio laboratory surveillance Regional reference laboratory Polio eradication