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two-dimensional atomically thin Pt layers on MXenes: the role of electronic effects during catalytic dehydrogenation of ethane and propane

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Nano Research 2024年第3期17卷 1251-1258页

作者： Zhe Li tobias K.Misicko Fan Yang Xiaopeng Liu Zhenwei Wu Xiaoyang Gao tao Ma Jeffrey t.Miller Daniela s.Mainardi Collin D.Wick Zhenhua Zeng Yang Xiao Yue Wu Department of Chemical and Biological Engineering Iowa State University618 Bissell RoadAmesIA 50011USA Institute for Micromanufacturing Louisiana Tech University505 Tech DriveRustonLA 71272USA Davidson school of Chemical Engineering Purdue University480 Stadium Mall DriveWest LafayetteIN 47907USA Michigan Center for Materials Characterization University of Michigan2800 Plymouth RdAnn Arbor MI 48109USA College of Engineering and science Louisiana Tech UniversityRustonLA 71272USA

Atomically thin Pt nanolayers were synthesized on the surface of Mo2tiC2 MXenes and used for the catalytic dehydrogenation of ethane and propane into ethylene and propylene,two important chemicals for the petrochemical *** compared with Pt nanoparticles.t.e atomically thin Pt nanolayer catalyst showed superior coke-resistance(no deactivation for 24 h),high activity(turnover frequencies.t.Fs)of 0.4–1.2 s^(-1)),and selectivity(>95%)toward ethylene and *** unique Pt nanolayer has a similar geometric surface to Pt nanoparticles,enabling the investigations of the electronic effect on the catalytic performance,where the geometric effect is *** is found that the electronic effect plays a critical role in dehydrogenative product selectivity and catalyst *** metal–support interaction is found dependent on the substrate and metal components,providing wide opportunities.t. explore high-performance MXene-supported metallic catalysts.

关键词： MXene catalysis alkane dehydrogenation nanolayers

Experimental study of friction dissipators for seismic protection of building structures

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Earthquake Engineering and Engineering Vibration 2011年第4期10卷 475-486页

作者： F. López-Almansa s.t. de la Cruz C. taylor technical Univers.t. of Catalonia Architecture Structures Department Universidad Autónoma de Ciudad Juárez Civil and Environmental Engineering Department Civil Engineering Department University of Bristol

this paper presents.t.e results from unidirectional shaking table tests of two reduced scale steel models of a building frame, with one and two floors, respectively. these frames incorporate friction dissipators at every floor. the inputs are sine-dwells and artificial and registered earthquakes. this study is part of a larger research project aiming to assess.t.e seismic efficiency of friction dissipators by means of an integrated numerical and experimental approach. Inside this framework, the main objectives of these experiments are to：（i） collect a wide range of results.t. calibrate a numerical model derived within the project, （ii） clarify some of the most controversial issues about friction dissipators （including behavior for inputs containing pulses, capacity to reduce resonance peaks, introduction of high frequencies in the response, and self- generated eccentricities）, （iii） better understand their dynamic behavior, （iv） provide insight on the feasibility and reliability of using simple friction dissipators for seismic protection of building structures and （v） characterize the hysteretic behavior of these devices. Most of these objectives are s.t.sfactorily reached and relevant conclusions are stated.

关键词： building structures earthquake engineering passive control friction energy dissipators experimentalverification shaking table tests

Conformally symmetric wormhole solutions supported by non-commutative geometry in f(Q,t)gravity

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Communications in theoretical Physics 2024年第2期76卷 111-124页

作者： Chaitra Chooda Chalavadi V Venkatesha N s Kavya s V Divya Rashmi Department of P.G.studies and Research in Mathematics Kuvempu UniversityShankaraghattaShivamogga 577451KarnatakaIndia Department of Mathematics Vidyavardhaka College of EngineeringMysuru—570002India

this paper investigates wormhole solutions within the framework of extended symmetric teleparallel gravity,incorporating non-commutative geometry,and conformal *** achieve this,we examine the linear wormhole model with anis.t.opic fluid under Gaussian and Lorentzian *** primary objective is.t. derive wormhole solutions while considering the influence of the shape function on model parameters under Gaussian and Lorentzian *** resulting shape function s.t.sfies all the necessary conditions for a traversable ***,we analyze the characteristics of the energy conditions and provide a detailed graphical discussion of the matter contents via energy ***,we explore the effect of anis.t.opy under Gaussian and Lorentzian ***,we present our conclusions based on the obtained results.

关键词： traversable wormhole f(Q t)gravity energy conditions non-commutative geometry conformal motion

Long-term follow-up of kidney transplant recipients admitted to a tertiary care transplant center with sARs-CoV-2

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World Journal of Virology 2024年第2期13卷 87-95页

作者： Emily E Zona Mina L Gibes Asha s Jain Jeannina A smith Jacqueline M Garonzik-Wang Didier A Mandelbrot sandesh Parajuli Division of Nephrology Department of MedicineUniversity of Wisconsin School of Medicine and Public HealthMadisonWI 53705United States Department of Infectious Disease University of Wisconsin Hospital and ClinicsMadisonWI 53705United States Department of surgery University of WisconsinMadisonWI 53705United States Department of Medicine University of Wisconsin School of Medicine and Public HealthMadisonWI 53705United States Department of Medicine University of Wisconsin School of Medicine and Public HealthUniversity of Wisconsin MadisonMadisonWI 53705United States

BACKGROUND Kidney transplant recipients(KtR)are at risk of severe coronavirus disease 2019(COVID-19)disease and mortality after severe acute respiratory syndrome coronavirus 2(sARs-CoV-2)*** predicted that hospitalization for COVID-19 and subsequent admission to the intensive care unit(ICU)would yield worse outcomes in *** was stratified by ICU *** of interest included risk factors for ICU admission and mortality,length of stay(LOs),respiratory symptoms at admission,all-cause graft failure at the last follow-up,and death related to *** 96 KtRs were hospitalized for sARs-COV-2 infection.21(22%)required ICU *** ICU group had longer hospital LOs(21.8 vs 8.6 days,Pto experience graft failure(81%vs 31%,Pthose admitted to the ICU,76%had death at last-follow up,and 71%had death related to *** factors for ICU admission included male sex(aHR:3.11,95%CI:1.04-9.34;P=0.04).Risk factors for all-cause mortality and COVID-19-related mortality included ICU admission and advanced age at sARs-CoV-2 *** was highest within a month of COVID-19 diagnosis,with the ICU group having increased risk of all-cause(aHR:11.2,95%CI:5.11-24.5;Pted mortality(aHR:27.2,95%CI:8.69-84.9;PsION ICU admission conferred an increased risk of mortality,graft failure,and longer ***-fifth of those hospit-alized died of COVID-19,reflecting the impact of COVID-19-related morbidity and mortality among KtRs.

关键词： Kidney transplants sARs-CoV-2 Intensive care unit admission Outcomes Graft failure

the spectrum of Nail Disorders in Patients with End-stage Renal Disease Undergoing Conservative treatment: A Case-Control study

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International Journal of Dermatology and Venereology 2024年第3期7卷 150-154页

作者： shigidi M.M.t. Department of Internal Medicine College of Medicine Jouf University Al Jouf 72388 Saudi Arabia Nephrology Division Department of Medicine Baraha Medical City North Khartoum State Khartoum 13311 Sudan

Objective: Various nail disorders have been reported in patients with chronic kidney disease. However, few studies have investigated nail disorders in patients with advanced chronic kidney disease. this study focused on nail disorders seen in patients with end-stage renal disease (EsRD) undergoing conservative treatment. Methods: A case-control study was conducted at Baraha Medical City in Khartoum state, sudan. Data on patients with EsRD who were on conservative treatment and presented for follow-up between March and september 2021 were collected. Patients' demographic features, nail findings on clinical examination, and laboratory results were recorded. the obtained data were compared with those on age- and sex-matched healthy individuals from the general population. the chi-square test and student t test were performed to analyze categorical and numerical variables, respectively. Results: Data on 78 patients with EsRD were studied. their mean age was 54.6 ± 17.6 years, and 45 (57.7%) were men. these patients were compared with 129 controls. Nail disorders were seen in 65 (83.3%) EsRD patients and 86 (66.6%) controls (P = 0.009). Patients with EsRD were found to be at increased relative risk of developing a wide spectrum of nail disorders. An absent lunula, half-and-half nails, nail dystrophy, terry's nails, onychomycosis, and koilonychia were the most common disorders and were seen in 44 (56.4%), 13 (16.7%), 10 (12.8%), 9 (11.5%), 6 (7.7%), and 5 (6.4%) patients, respectively. Patients with EsRD had a statistically significant risk of developing above diseases (all P sion: the current study demonstrated a wide spectrum of nail disorders in patients with EsRD undergoing conservative treatment. Further studies are essential to understand their pathogenesis. © 2024 Hospital for skin Diseases (Institute of Dermatology), Chinese Academy of Medical sciences, and Chinese Medical Association, published by Wolters Kluwer, Inc.

关键词： chronic kidney disease disease spectrum end-stage renal disease nail disorders

Wild Nutrition’s Food-Grown® Magnesium supplementation Increases sleep Quality and sleep Duration and Reduces stress in a Healthy Adult Population: A Double-Blind, Randomised, Placebo-Controlled study

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Food and Nutrition sciences 2024年第7期15卷 509-523页

作者： David Briskey Jane Erickson Chelsie smith Amanda Rao school of Human Movement and Nutrition sciences University of Queensland Brisbane Australia RDC Clinical Brisbane Australia

Background: Magnesium, an essential mineral crucial for various bodily functions, has been shown to pos.t.vely influence sleep patterns. this study aimed to evaluate the efficacy of Food-Grown® magnesium in enhancing sleep quality and duration, as well as overall well-being. Methods: Eighty participants were randomly assigned to receive either 80 mg of Food-Grown® magnesium or a placebo (microcrystalline cellulose) daily for 8 weeks. Participants completed questionnaires assessing sleep quality, daytime drowsiness, quality of life, anxiety, and stress levels. Additionally, participants maintained daily sleep diaries and wore wrist-worn actigraphy devices. the primary outcome measured was.t.e change in sleep quality and duration. Results: seventy-one participants fulfilled all study requirements (35 in the active group and 36 in the placebo group). Magnesium supplementation significantly improved reported sleep quality, with the active group showing a 32% increase compared to 16% in the placebo group (p = 0.034). Moreover, magnesium supplementation led to a decrease in reported stress scores at week 8 compared to the placebo group (3.7 ± 2.6 vs. 5.5 ± 3.1, respectively). Both the magnesium and placebo groups exhibited significant increases in reported sleep duration and reductions in time to fall asleep, sleep disturbance, sleep latency, sleep medication usage, and total Pittsburgh sleep Quality Index score at week 8 compared to baseline. Conclusion: Magnesium supplementation notably enhanced sleep quality and reduced stress levels compared to the placebo group. these findings highlight the potential of magnesium as a beneficial supplement for improving sleep quality and overall well-being.

关键词： Magnesium sleep Quality sleep Duration stress Food-Grown

Elevation trans.t.on of aquatic insects closely matches a thermal feature in the Yungas of Northwestern Argentina

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Journal of Mountain science 2024年第2期21卷 433-448页

作者： Alexandra BUItRAGO-GUACANAME Carlos MOLINERI Andrés LIRA-NORIEGA Daniel Andrés DOs sANtOs Neotropical Biodivers.t. Institute(CONICEt-UNt) UNT-DomesHorco Molle S/N4107 TucumánArgentina CONACYt Research Fellow Network of Advanced Molecular StudiesInstitute of Ecology A.COld Road to Coatepec 351El HayaCP 91073XalapaVeracruzMexico Biostatistics Chair Faculty of Natural Sciences and IMLNational University of TucumánSan Miguel de TucumánMiguel Lillo 2054000 TucumánArgentina

temperature is a key factor that shapes.t.e distribution of *** knowledge about how species respond to temperature is relevant to devise strategies for addressing the impacts of climate *** insects are particularly vulnerable to climate change,yet there is still much to learn about their ecology and *** the Yungas ecoregion of Northwestern Argentina,cold-and warm-adapted species of the orders Ephemeroptera,Plecoptera,and trichoptera(EPt)are segregated by *** modeled the ecological niche of south American EPt species in this region using available data and projected their potential distribution in geographic *** were grouped based on their ecogeographic similarity,and we analyzed their replacement pattern along elevation gradients,focusing on the ecotone where opposing thermal preferences *** this interface,we identified critical points where the combined incidence of cold and warm assemblages maximizes,indicating a significant trans.t.on *** found that the Montane Cloud Forest holds.t.e interface,with a particularly greater suitability at its lower *** main axis of the interface runs in a N-s direction and falls between 14°C-16°C mean annual *** probability of a particular location within a basin being classified as part of the interface increases as Kira’s warmth index approaches a score around *** the interface is critical for defining the thermal limits of species distribution and designing biomonitoring *** in the location of thermal constants related to mountainous ecotones may cause vertical displacement of aquatic insects and vegetation *** have recognized significant temperature thresholds.t.at serve as indicators of suitability for the *** global warming is anticipated to shift these indicators,we suggest using them to monitor the imprints of climate change on mountain ecosystems.

关键词： Austral Yungas Ecological Niche Model Ephemeroptera Kira’s warmth index Plecoptera trichoptera

Improved state-space Modelling for Microgrids Without Virtual Resistances

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Journal of Modern Power systems and Clean Energy 2024年第2期12卷 584-596页

作者： Paranagamage s.A.Peiris shaahin Filizadeh Dharshana Muthumuni Department of Electrical and Computer Engineering University of ManitobaWinnipegMBR3T 5V6Canada Manitoba HVDC Research Center 211 Commerce DriveWinnipegMBR3P 1A3Canada IEEE

Power converters and their interfacing networks are often treated as modular state-space blocks for small-signal stability studies in microgrids.t.ey are interconnected by matching the input and output states of the network and *** resistors have been widely used in existing models.t. generate a voltage for state-space models of the network that require voltage *** paper accurately quantifies.t.e adverse impacts of adding the virtual resistance and proposes an alternative method for network modelling that eliminates.t.e requirement of the virtual resistor when interfacing converters with *** proposed nonlinear method allows initialization,time-domain simulations of the nonlinear model,and linearization and eigenvalue generation.A numerically linearized small-signal model is used to generate eigenvalues and is compared with the eigenvalues generated using the existing modelling method with virtual *** of the existing method and improvements offered by the proposed modelling method are clearly *** transient(EMt)simulations using detailed switching models are used for validation of the proposed modelling method.

关键词： Low-voltage converter state-space modelling dynamic phasor time-domain simulation eigenvalue analysis

A study of the Comets with Large Perihelion Distances C/2019 L3(AtLAs)and C/2019 O3(Palomar)

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Research in Astronomy and Astrophysics 2024年第9期24卷 199-213页

作者： Alberto s.Betzler Centro de Ciencia e tecnologia em Energia e sustentabilidade Universidade Federal do Recôncavo da BahiaFeira de SantanaBahia44.085-132Brazil

this work analyzes.t.e photometric data of the Oort spike comets C/2019 L3(AtLAs)and C/2019 O3(Palomar)obtained between 2016 and 2023 by the AtLAs network and the Belgian Olmen *** comets Palomar and AtLAs have a typical and unusually high activity level,respectively,based on the Afρparameter corrected to phase angle zero at *** absolute magnitude of comets AtLAs and Palomar in the o-band is 4.71±0.05 and 4.16±0.02 *** cometary activity of comets AtLAs and Palomar probably began at r>13 au before perihelion and will end at r>14 au after perihelion,which means.t.at they could remain active until the second half of *** nucleus of comet AtLAs has a minimum radius of 7.9 km,and the nucleus of comet Palomar could be a little *** c-o colors of the comets AtLAs and Palomar are redder and bluer,respectively,at perihelion than the solar twin YBP *** comets showed a bluish trend in the coma color with decreasing heliocentric *** Palomar probably had two outbursts after its perihelion,each releasing about 10^(8)kg of *** slopes of the photometric profile of the comae of these comets were between 1and 1.5,indicating a steady state during the observation campaign.

关键词： individual C/2019 L3(AtLAs) C/2019 O3(Palomar) techniques:photometric methods:data analysis