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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

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Development,validation,and transportability of several machine-learned,non-exercise-based VO_(2max)prediction models for older adults

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journal of Sport and health Science 2024年第5期13卷 611-620页

作者： Benjamin T.Schumacher michael j.Lamonte Andrea Z.LaCroix Eleanor m.Simonsick Steven p.hooker humberto parada jr. john Bellettiere Arun Kumar herbert Wertheim School of public health and human Longevity Science University of California San DiegoLa JollaCA 92093USA Department of Epidemiology and Environmental health School of Public Health and Health ProfessionsUniversity at BuffaloState University of New YorkBuffaloNY 14214USA Translational Gerontology Branch Intramural Research ProgramNational Institute on AgingNational Institutes of HealthBaltimoreMD 21225USA College of health and human Services San Diego State UniversitySan DiegoCA 92182USA Division of Epidemiology and Biostatistics School of Public HealthSan Diego State UniversitySan DiegoCA 92182USA University of California San Diego moores Cancer Center La JollaCA 92093USA Computer Science and Engineering and halicioglu Data Science Institute University of California San DiegoLa JollaCA 92093USA

Background:There exist few maximal oxygen uptake(VO_(2max))non-exercise-based prediction equations,fewer using machine learning(mL),and none specifically for older *** direct measurement of VO_(2max)is infeasible in large epidemiologic cohort studies,we sought to develop,validate,compare,and assess the transportability of several mL VO_(2max)prediction ***:The Baltimore Longitudinal Study of Aging(BLSA)participants with valid VO2_(max)tests were included(n=1080).Least absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine(SVm)algorithms were trained to predict VO_(2max)*** developed these algorithms for:(a)the overall BLSA,(b)by sex,(c)using all BLSA variables,and(d)variables common in aging ***,we quantified the associations between measured and predicted VO_(2max)and ***:The age was 69.0±10.4 years(mean±SD)and the measured VO_(2max)was 21.6±5.9 mL/kg/*** absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine yielded root mean squared errors of 3.4 mL/kg/min,3.6 mL/kg/min,3.4 mL/kg/min,3.6 mL/kg/min,and 3.5 mL/kg/min,*** quartiles of measured VO_(2max)showed an inverse gradient in mortality *** VO_(2max)variables yielded similar effect estimates but were not robust to ***:measured VO_(2max)is a strong predictor of *** mL can improve the accuracy of prediction as compared to simpler approaches but estimates of association with mortality remain sensitive to *** studies should seek to reproduce these results so that VO_(2max),an important vital sign,can be more broadly studied as a modifiable target for promoting functional resiliency and healthy aging.

关键词： Cardiorespiratory fitness prediction algorithms Epidemiology mortality

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A hydrodynamic modelling of wave-activated bodies for wavelet marine regions

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CLEAN ENERGY 2024年第2期8卷 35-47页

作者： peh, j. S. muhieldeen, mohammed W. Shuaib, N. h. UCSI Univ Fac Engn Technol & Built Environm Mech Engn Dept Kuala Lumpur 56000 Malaysia mTC Engineer Sdn Bhd Shah Alam Selangor Malaysia

Recently, most wave energy research has targeted sea areas with high power density under extreme wave conditions for deployment. This trend often leads to higher energy costs for wave power plants. however, many marine areas with low power density, characterized by wavelet conditions and less destructive forces than extreme wave conditions, remain underexplored. Therefore, this study aimed to propose a wave-activated body model for sea regions with wavelet conditions. The wave-activated body design process encompassed site selection, parameter determination, geometry design, comparison and performance evaluation using the ANSYS (R) AQWA model. The results indicated that the proposed device achieved the desired heave motion, with an amplitude range of 1.2 to -2.5 m, validating its potential for deployment in marine regions with wavelet conditions. Notably, while the proposed design is optimized for wavelet conditions, it was found to have potential limitations in extreme wave environments. This observation emphasizes the challenge of formulating a generalized design suitable for both conditions. Consequently, it is pivotal for wave-activated body designs to be customized based on the specific ocean conditions they target, underscoring the need for specialized designs of wave energy converters that consider the unique wave characteristics of their deployment sites. A wave-activated body is designed for energy generation in ocean regions with wavelet conditions. hydrodynamic modelling is carried out for two locations with different wave characteristics to determine the optimum conditions for deployment. Graphical Abstract

关键词： wave energy converter South China sea renewable and sustainable energy wavelet ANSYS AQWA hydrodynamic wave-activated bodies ENERGY ImpACT

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Abalone shell-derived mg-doped mesoporous hydroxyapatite microsphere drug delivery system loaded with icariin for inducing apoptosis of osteosarcoma cells

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Biomaterials Translational 2024年第2期5卷 185-196页

作者： Liu K. Cheng m. huang h. Yu h. Zhao S. Zhou j. Tie D. Wang j. pan p. Chen j. marine College Shandong University Shandong Province Weihai China State Key Laboratory of mineral processing Beijing China College of Biological Science and Technology Fuzhou University Fujian Province Fuzhou China

hydroxyapatite (hAp) porous microspheres with very high specific surface area and drug loading capacity, as well as excellent biocompatibility, have been widely used in tumour therapy. mg2+ is considered to be a key factor in bone regeneration, acting as an active agent to stimulate bone and cartilage formation, and is effective in accelerating cell migration and promoting angiogenesis, which is essential for bone tissue repair, anti-cancer, and anti-infection. In this study, abalone shells from a variety of sources were used as raw materials, and mg2+-doped abalone shell-derived mesoporous hAp microspheres (mg-hAp) were prepared by hydrothermal synthesis as mg2+/icariin smart dual delivery system (ICA-mg-hAp, ImhA). With increasing of mg2+ doping, the surface morphology of hAp microspheres varied from collapsed macroporous to mesoporous to smooth and non-porous, which may be due to mg2+ substitution or coordination in the hAp lattice. At 30% mg2+ doping, the mg-hAp microspheres showed a more homogeneous mesoporous morphology with a high specific surface area (186.06 m2/g). The ImhA microspheres showed high drug loading (7.69%) and encapsulation rate (83.29%), sustained mg2+ release for more than 27 days, sustained and stable release of icariin for 60 hours, and good responsiveness to ph (ph 6.4 > ph 5.6). In addition, the ImhA delivery system stimulated the rapid proliferation of bone marrow mesenchymal stem cells and induced apoptosis in mG63 cells by blocking the G2 phase cycle of osteosarcoma cells and stimulating the high expression of apoptotic genes (Bcl-2, caspase-3,-8,-9). This suggests that the abalone shell-based ImhA may have potential applications in drug delivery and tumour therapy. © 2024, Chinese medical multimedia press Co Ltd. All rights reserved.

关键词： abalone shell drug delivery hydroxyapatite microspheres magnesium doping osteosarcoma

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Ecosystem Services of Grazed Grasslands in the Flooding pampa

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phyton-International journal of Experimental Botany 2024年第6期93卷 1179-1202页

作者： Elizabeth j.jacobo Adriana m.Rodríguez Facultad de Agronomía Área de AgroecologíaUniversidad de Buenos AiresBuenos Aires1417Argentina Facultad de Agronomía Departamento de Producción AnimalUniversidad de Buenos AiresBuenos Aires1417Argentina

The Flooding pampa grasslands are the last remnant of the Rio de la plata grasslands in ***-genic interventions have led to severe degradation and,as a result,the ecosystem services provided by the grass-lands are declining,in terms of provisioning,regulating,and supporting *** synthesized the existing literature on the ecosystem goods and services provided by these grasslands under grazing in different conditions and conservation *** found that plant and animal diversity and primary production are the most studied ecosystem services,while climate regulation,water supply,nutrient cycling,meat production and erosion control,in that order,are less *** services are *** grazing and glyphosate spraying are the main drivers of grassland *** grazing and conservative stocking rates have been shown to reverse degradation and demonstrate that livestock production is compatible with ecosystem conserva-tion by maintaining regulating and provisioning *** these management strategies are poorly integrated,improving their implementation will require important changes in farmers’decisions and the development of policies that create the economic conditions for this to *** is needed to understand the conditions that prevent the knowledge generated from being transferred to producers and translated into practices that would improve the provision of ecosystem services.

关键词： Salado basin sustainability biodiversity rangelands meat production adaptative multi paddock grazing process technologies agroecology

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Carbon monoxide as C1 Building Block in Fine Chemical Synthesis

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Chinese journal of Chemistry 2024年第2期42卷 199-221页

作者： Rui m.B.Carrilho mario j.F.Calvete Gabor mikle Laszlo Kollar mariette m.pereira University of Coimbra Coimbra Chemistry CentreDepartment of ChemistryRua Larga3004-535 CoimbraPortugal Department of General and Inorganic Chemistry and ELKh-pTE Research Groupfor Selective Chemical Syntheses University of PecsIfjusag utja 6H-7624 PecsHungary

Carbon monoxide(CO)has become one of the most relevant and versatile renewable C1 building blocks for chemical synthesis,especially in the fine chemicals industry,due to the development of efficient and selective catalysts for its *** this review,we present a comprehensive critical analysis of the last 10 years literature on the use of CO as a renewable feedstock for fine chemicals *** review is organized by type of catalytic reaction,namely alkene and alkyne carbonylation,hydroformylation,carbonylation of aryl halides,carbonylative cross-coupling and C-h *** examples of the synthesis of relevant building blocks and/or known pharmaceuticals are *** is placed on examples of utilizing CO as the C1 building block in one or more catalytic *** catalyst used and the reaction conditions are consistently presented throughout all of the examples.

关键词： Carbon monoxide Fine chemicals Carbonylation hydroformylation C-h functionalization

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Effect of stress-dependent microannulus aperture on well leakage

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journal of Rock mechanics and Geotechnical Engineering 2024年第6期16卷 1967-1976页

作者： meng meng Luke p.Frash j.William Carey mohamed mehana Wenfeng Li Bailian Chen Earth and Environmental Sciences Los Alamos National LaboratoryLos AlamosNMUSA

Debonding at the cement-casing interface is recognized as a principal failure mechanism leading to CO_(2) leakage in *** detachment gives rise to a microannulus,which notably possesses greater permeability than undamaged cement,undermining its sealing ***,the permeability of the microannulus is regarded as a uniform value throughout the ***,fundamentally,a microannulus is one type of fracture,and its gap or aperture size is affected by the effective *** this work,we developed a unique experimental *** equipment facilitates the curing of cement inside a steel casing,the formation of a microannulus between the casing and the cement,and the investigation of the fluid flow dynamics along the microannulus under laboratory-replicated in situ *** microannulus was formed by injecting fluid from one end of the setup,and receiving similar amount of fluid on the other end signified the development of the leakage ***,strain gauges affixed to the casing’s external surface yielded key information on the microannulus’s opening and *** observed a noticeable decline in microannulus hydraulic aperture(or permeability)in relation to effective stress and an exponential equation fits their *** findings also indicate a distinct behavior when comparing liquid CO_(2) with ***,it is easier for liquid CO_(2) to create the ***,the hydraulic aperture range for this microannulus(0.7-6 mm)is considerably smaller than that created by water flow(2-17 mm).Finally,we integrated the stressdependent microannulus aperture size into the combined analysis of well mechanical integrity and well *** outcomes consistently demonstrated that when factoring in the stress-dependent aperture sizes,the leakage rates are 3e5 times compared to a fixed aperture *** traditional assumption of a constant aperture significantly underestimates fluid leakage risks.

关键词： microannulus Leakage assessment Aperture size Triaxial experiment Carbon sequestration

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Interfacial stress engineering toward enhancement of ferroelectricity in Al doped hfO_(2)thin films

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Chinese physics B 2024年第9期33卷 637-643页

作者： S X Chen m m Chen Y Liu D W Cao G j Chen Department of microelectronics Jiangsu UniversityZhenjiang 212013China Department of physics Jiangsu UniversityZhenjiang 212013China Guangdong–hong Kong–macao joint Laboratory for Intelligent micro-Nano Optoelectronic Technology Foshan UniversityFoshan 528225China

Ferroelectric hfO_(2)has attracted much attention owing to its superior ferroelectricity at an ultra-thin thickness and good compatibility with Si-based complementary metal-oxide-semiconductor(CmOS)***,the crystallization of polar orthorhombic phase(o-phase)hfO_(2)is less competitive,which greatly limits the ferroelectricity of the as-obtained ferroelectric hfO_(2)thin ***,the crystallization of o-phase hfO_(2)can be thermodynamically modulated via interfacial stress *** this paper,the growth of improved ferroelectric Al doped hfO_(2)(hfO_(2):Al)thin films on(111)-oriented Si substrate has been *** analysis has suggested that nonpolar monoclinic hfO_(2):Al grown on(111)-oriented Si substrate suffered from a strong compressive strain,which promoted the crystallization of(111)-oriented o-phase hfO_(2)in the as-grown hfO_(2):Al thin *** addition,the in-plane lattice of(111)-oriented Si substrate matches well with that of(111)-oriented o-phase hfO_(2),which further thermally stabilizes the o-phase hfO_(2).Accordingly,an improved ferroelectricity with a remnant polarization(2p_(r))of 26.7C/cm^(2) has been *** results shown in this work provide a simple way toward the preparation of improved ferroelectric hfO_(2)thin films.

关键词： improved ferroelectricity interfacial stress engineering compressive strain hfO_(2)

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measurement,associations,patterns,and promotion:Unveiling vital areas in physical activity epidemiology

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journal of Sport and health Science 2024年第5期13卷 605-607页

作者： Kara m.Whitaker Guest editor michael j.Lamonte Department of health&human physiology University of IowaIowa CityIA 52242USA Department of Epidemiology and Environmental health University of BuffaloBuffaloNY 14214 USA

physical activity(pA)epidemiology first emerged as a new field of study around the 1950s with publication of seminal investigations on London civil servants1 and has continued to evolve as a scientific discipline to present *** subdiscipline of epidemiology studies the frequencies,distributions,and dynamics of pA and its impact on human health,morbidity,and *** over the past 75 years has demonstrated numerous health benefits of *** on these research findings,the World health Organization recommends adults aged 18-64 years engage in at least 150-300 min of moderate-intensity aerobic pA per week,or at least 75-150 min of vigorous-intensity aerobic pA per week,or a combination of both intensities.

关键词： epidemiology promotion continued

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Use of ketamine for severe asthma exacerbation in a pregnant patient with persistent bronchospasm: A case report

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Emergency and Critical Care medicine 2024年第3期4卷 130-133页

作者： johnson m. Abbas m. Abdo j. mansour m. jones j. pharmacy Department Beaumont Health Dearborn MI United States Emergency Center Beaumont Health Dearborn MI United States

Background Estimated 4%-8% of pregnancies are complicated by asthma. Adequate management in this population is critical to minimize complications. patients presenting with asthma exacerbation are typically managed with standard bronchodilators and systemic corticosteroids. however, additional agents may be used in patients with refractory asthma exacerbation. Ketamine has been used in refractory bronchospasm, although its efficacy in published literature is heterogeneous. Case presentation We present a case of a pregnant patient with severe asthma exacerbation refractory to standard and salvage treatment who achieved termination of bronchospasm with ketamine infusion. Conclusion After receiving ketamine infusion for several days, the patient had improved air flow and achieved successful extubation, without experiencing rebound bronchospasm. Although this individual clinical case alone cannot change guidelines or directives to use in refractory asthma exacerbations, it offers a possible treatment option to patients and providers in unusually severe cases with extenuating risk factors. © Wolters Kluwer health, Inc. All rights reserved.

关键词： Asthma Bronchospasms Case Report Ketamine pregnancy

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