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emission colour tuning in KLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)phosphor

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Journal of Rare earths 2024年第1期42卷 57-65,I0002页

作者： Janani K Gayathri e Vijayatha V Ramasubramanian S Thiyagarajan p Department of Science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia Department of Sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia Department of physics Anna UniversityChennaiIndia

KLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)(Ln=Y,Yb,Gd)phosphors were.prepared by solid-state reaction *** each of the Yb^(3+)/er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and *** luminescence emissions of green and red colour were detected for the synthesized *** changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the.prepared *** the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green *** rare-earth er/Ho doped KYbF4shows strong red emission compared to other ***_(4):Yb,er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,er-doped KGdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 *** photoluminescence studies and decay curve analysis were carried out using UV light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped KYbF_(4)*** study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride.phosphor.

关键词： Rare earths energy transfer upconversion Downshifting Colour coordinates

Alzheimer's disease and low-dose radiation therapy:A new hope

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Radiation Medicine and protection 2024年第1期5卷 1-6页

作者： Neal e.Dunlap Robert p.Friedland Lu Cai Department of Radiation Oncology University of Louisville School of MedicineLouisvilleKY40202USA Department of Neurology The University of Louisville School of MedicineLouisvilleKY40202USA pediatric Research Institute Departments of PediatricsPharmacology and ToxicologyUniversity of Louisville School of MedicineLouisvilleKY40202USA

The concept of low-dose radiation(LDR)-induced hormetic re.ponses was initially observed approximately 70 years ago and systematically reviewed along with the discovery of LDR-induced adaptive re.ponses in a cytogenetic in vitro study in *** the end of the 1990s,discussions regarding the.potential applications of LDRinduced hormesis and adaptive re.ponses for preventing or treating chronic diseases,such as Alzheimer’s disease(AD)had taken *** 2016,reports on radiotherapy for the subjects with AD and for genetic AD model mice were ***,several preclinical studies with animal models of AD and clinical studies in AD subjects were conducted.A significant milestone was achieved with the online availability of a new Systematic Review based on qualified publications from these.preclinical and clinical *** mini-review provides a concise historical introduction to LDR-induced hormesis and adaptive re.ponses with discussion of AD radiotherapy with either LDR or relatively high dose *** of this Systematic Review cover promising outcomes,challenges,and new questions,followed by discussion of potential mechanisms.

关键词： Alzheimer’s disease Low-dose radiation Radiation adaptive re.ponse Radiation hormesis

e.ploring 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

Ca-based materials derived from calcined cigarette butts for CO_(2)capture and thermochemical energy storage

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Journal of environmental Sciences 2024年第6期140卷 230-241页

作者： Nabil Amghar Virginia Moreno pedro e.Sánchez-Jiménez Antonio perejón Luis A.pérez-Maqueda Instituto de Ciencia de Materiales de Sevilla C.S.I.C.-Universidad de SevillaC.Américo Vespucio4941092 SevillaSpain Instituto de Tecnología de Materiales(ITM) Universitat Politècnica de València(UPV)Plaza Ferrándiz y Carbonell 1AlcoyAlicante 03801Spain Departamento de Química Inorgánica Facultad de QuímicaUniversidad de Sevilla41012 SevillaSpain

Cigarette butts(CBs)are one of the most common types of litter in the *** to the toxic substances they contain,the waste generated poses a harmful risk to the environment,and therefore there is an urgent need for alternative solutions to landfill ***,this work presents a possible revalorization of this waste material,which implies interesting environmental *** were used as sacrificial te.plates for the.preparation of CaO-based materials by impregnation with calcium and magnesium nitrates followed by flaming *** materials presented enhanced porosity for their use in the Calcium Looping process applied either to thermochemical energy storage or CO_(2)capture *** influence of the concentration of Ca and Mg in the impregnating solutions on the multicycle reactivity of the samples was *** improved multicycle.performance was obtained in terms of conversion for both applications.

关键词： Cigarette butts Calcium-Looping CO_(2)Capture Thermochemical energy storage

physical activity volume,frequency,and intensity:Associations with hypertension and obesity over 21 years in Australian women

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Journal of Sport and Health Science 2024年第5期13卷 631-641页

作者： Gregore I.Mielke Ding Ding Shelley e.Keating Bruno p.Nunes Ruth Brady Wendy J.Brown School of public Health The University of QueenslandBrisbaneQLD 4006Australia Sydney School of public Health Faculty of Medicine and HealthThe University of SydneySydneyNSW 2006Australia The Charles perkins Centre The University of SydneySydneyNSW 2006Australia School of Human Movement and Nutrition Sciences The University of QueenslandBrisbaneQLD 4072Australia School of Nursing Federal University of PelotasPelotasRio Grande do Sul 96010-610Brazil Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4226Australia

Background:Optimal patterns of accrual of recommended levels of physical activity(pA)for prevention of hypertension and obesity are not *** overall aim of this study was to investigate whether different patterns of accumulation of pA are differentially associated with hypertension and obesity in Australian women over 21 ***,we investigated whether,for the same weekly volume of pA,the number of sessions(frequency)and vigorousness of pA(intensity)were associated with a reduction in the occurrence of hypertension and obesity in ***:Data from the 1973-1978 and 1946-1951 cohorts of the Australian Longitudinal Study on Women's Health were analyzed(n=20,588;12%-16%with a Bachelor's or higher degree).Self-reported pA,hypertension,height,and weight were collected using mail surveys every 3 years from 1998/2000 to 2019/*** estimating equation models with a 3-year lag model were used to investigate the association of pA volume(metabolic equivalent min/week)(none;33-499;500-999;≥1000,weekly frequency(none;1-2 times;3-4times;5-7 times;≥8 times),and the.proportion of vigorous pA to total volume of pA(none;0%;1%-33%;34%-66%;67%-100%)with odds of hypertension and obesity from 2000 to ***:The cumulative incidence of hypertension was 6%in the 1973-1978 and 23%in the 1946-1951 cohort;27%of women in the 1973-1978;and 15%in the 1946-1951 cohort developed obesity over the ***,a higher volume of pA was associated with reduced odds of hypertension and *** the volume of pA was considered,the odds of hypertension did not vary according to the frequency or intensity of ***,increased proportion of vigorous pA to the total volume of pA was associated with a small additional reduction in the risk of obe ***:pA volume appears to be more important than the.pattern of accumulation for the.prevention of hypertension and *** more sessions,particularly of vigorous-intensity pA,may provide extr

关键词： physical activity Frequency Intensity Incidences epidemiology Women

Collisionless shock acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves

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Matter and Radiation at extremes 2024年第2期9卷 12-25页

作者： J.-R.Marquès L.Lancia p.Loiseau p.Forestier-Colleoni M.Tarisien e.Atukpor V.Bagnoud C.Brabetz F.Consoli J.Domange F.Hannachi p.Nicolaï M.Salvadori B.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance CeA DAMDIF91297 Arpajon CedexFrance Universitéparis-Saclay CEALMCE91680 Bruyères-le-ChatelFrance CeNBG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany University of Darmstadt Schloßgartenstr.764289 DarmstadtGermany eNeA Fusion and Technologies for Nuclear Safety Department C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly CeLIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance Universitéparis-Saclay CEALIDYL91191 Gif-sur-YvetteFrance

We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[Marquès et al.,*** 28,023103(2021)].In a continuation of this numerical work,we study e.perimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the.picosecond laser,and by tailoring both sides of the gas *** tailoring,the acceleration is transverse to the laser axis,with a low-energy e.ponential spectrum,produced by Coulomb *** the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the.plasma are *** forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(CSA).The spatiote.poral evolution of the.plasma profile is characterized by optical shadowgraphy of a probe *** refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the.plasma *** with the e.perimental results allows estimation of the thickness and near-critical density of the.plasma slab produced by tailoring both sides of the gas *** parameters are in good agreement with those required for CSA.

关键词： acceleration hydrodynamic collision

Factors that influence the results of indirect decompression e.ploying oblique lumbar interbody fusion

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World Journal of Orthopedics 2024年第8期15卷 734-743页

作者： Andrey e Bokov Svetlana Y Kalinina Mingiyan I Khaltyrov Alexandr p Saifullin Anatoliy A Bulkin Department of Neurosurgery Institute of Traumatology and OrthopedicsPrivolzhsky Research Medical UniversityNizhny Novgorod603005Russia Department of Traumatology Orthopedics and NeurosurgeryPrivolzhsky Research Medical UniversityNizhny Novgorod603005Russia

BACKGROUND Indirect decompression is one of the.potential benefits of anterior reconstruction in patients with spinal *** the other hand,the reported rate of revision surgery after indirect decompression highlights the necessity of working out prediction models for the radiographic results of indirect decompression with assessing their clinical *** To assess factors that influence radiographic and clinical results of the indirect decompression in patients with stenosis of the lumbar *** This study is a single-center cross-sectional evaluation of 80 consecutive.patients(17 males and 63 females)with lumbar spinal stenosis combined with the instability of the lumbar spinal *** underwent single level or bisegmental spinal instrumentation e.ploying oblique lumbar interbody fusion(OLIF)with percutaneous pedicle screw *** results of the indirect decompression were assessed using computerized tomography,while MacNab scale was used to assess clinical *** After indirect decompression e.ploying anterior reconstruction using OLIF,the statistically significant increase in the disc space height,vertebral canal square,right and left lateral canal depth were detected(Рe median(M)relative vertebral canal square increase came toМ=24.5%with 25%-75%quartile border(16.3%;33.3%)if indirect decompression was achieved by restoration of the segment *** patients with the reduction of the upper vertebrae slip,the median of the relative increase in vertebral canal square accounted for 49.5%with 25%-75%quartile border(2.35;99.75).Six out of 80 patients(7.5%)presented with unsatisfactory results because of residual nerve root *** critical values for lateral recess depth and vertebral canal square that were associated with indirect decompression failure were 3 mm and 80 mm2 *** Indirect decompression e.ploying anterior reconstruction is achieved by the increase in disc height al

关键词： Indirect decompression Anterior reconstruction Central lumbar spinal stenosis Degenerative spondylolisthesis Lateral recess stenosis Spinal instability Oblique lateral interbody fusion

miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High power Laser Science and engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold e.Beyreuther F.-e.Brack F.Kroll J.pawelke J.D.Schilz M.Schneider U.Schramm M.e.p.Umlandt K.Zeil T.Ziegler J.Metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum Freiburg FreiburgGermany

Laser plasma accelerators(LpAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new e.perimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such e.periments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single.proton bunches to allow for fast online *** we.present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LpA proton *** e.periments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

Impact of device resistances in the.performance of graphene‑based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期17卷 87-97页

作者： O.Castelló Sofía M.López Baptista K.Watanabe T.Taniguchi e.Diez J.e.Velázquez-pérez Y.M.Meziani J.M.Caridad J.A.Delgado-Notario Department of Applied physics University of Salamanca37008 SalamancaSpain Unidad de excelencia en Luz y Materia estructurada(LUMeS) University of Salamanca37008 SalamancaSpain Research Center for electronic and Optical Materials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for Materials Nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Nanotechnology Group USAL-NanolabUniversity of Salamanca37008 SalamancaSpain

In recent years,graphene field-effect-transistors(GFeTs)have demonstrated an outstanding potential for terahertz(THz)photodetection due to their fast re.ponse and *** features are essential to enable emerging THz applications,including 6G wireless communications,quantum information,bioimaging and ***,the overall performance of these.photodetectors may be utterly compromised by the impact of internal resistances presented in the device,so-called access or parasitic *** this work,we.provide a detailed study of the influence of internal device resistances in the.photore.ponse of high-mobility dual-gate GFeT *** dual-gate architectures allow us to fine tune(decrease)the internal resistance of the device by an order of magnitude and consequently demonstrate an improved re.ponsivity and noise-equivalent-power values of the.photodetector,*** results can be well understood by a series resistance model,as shown by the excellent agreement found between the e.perimental data and theoretical *** findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene.photodetectors.

关键词： Graphene THz photodetector Field-effect transistor plasmonic