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Crystal field and magnetism with Wannier functions: rare-earth doped aluminum garnets

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Journal of Rare Earths 2015年第12期33卷 1316-1323页

作者： eva Mihóková Pavel Novák Valentin V.Laguta Institute of Physics Czech Academy of Sciences

Using the recently developed method we calculated the crystal field parameters m yttrium anct lutetium aluminum garnets doped with seven trivalent Krarners rare-earth ions. We then inserted calculated parameters into the atomic-like Hamiltonian taking into account the electron-electron, spin-orbit and Zeeman interactions and determined the multiplet splitting by the crystal field as well as magnetic tensors. We compared calculated results with available experimental data. Very good agreement with the spectroscopic data and qualitative agreement with experimental tensors was found.

关键词： crystal field ab initio calculations gamets rare earths

Interaction of silver nanoparticles with mediterranean agricultural soils: Lab-controlled adsorption and desorption studies

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Journal of Environmental Sciences 2019年第9期31卷 205-216页

作者： Laura Torrent eva Margui Ignasi Queralt Manuela Hidalgo Monica Iglesias Department of Chemistry University of Girona C/M. Aurelia Capmany 69 17003 Girona Spain Institute of Environmental Assessment and Water Research (IDAEA-CSIC) C. Jordi Girona 28-26 08034 Barcelona Spain

The production of silver nanoparticles(AgNPs) has increased tremendously during recent years due to their antibacterial and physicochemical properties. As a consequence, these particles are released inevitably into the environment, with soil being the main sink of disposal. Soil interactions have an effect on AgNP mobility, transport and bioavailability. To understand AgNP adsorption processes, lab-controlled kinetic studies were *** tests performed with five different Mediterranean agricultural soils showed that cation exchange capacity and electrical conductivity are the main parameters controlling the adsorption processes. The adsorption kinetics of different sized(40, 75, 100 and 200 nm)and coated(citrate, polyvinylpyrrolidone and polyethyleneglycol(PEG)) AgNPs indicated that these nanoparticle properties have also an effect on the adsorption *** assess the mobility and bioavailability of AgNPs and to determine if their form is maintained during adsorption/desorption processes, loaded soils were submitted to leaching tests three weeks after batch adsorption studies. The DIN 38414-S4 extraction method indicated that AgNPs were strongly retained on soils, and single-particle inductively coupled plasma mass spectrometry confirmed that silver particles maintained their nanoform, except for 100 nm PEG-AgNPs and 40 nm citrate-coated AgNPs. The DTPA(diethylenetriaminepentaacetic acid) leaching test was more effective in extracting silver,but there was no presence of AgNPs in almost all of these leachates.

关键词： Silver nanoparticles Agricultural soils Sorption kinetics Leaching tests Single-particle inductively coupled plasma mass spectrometry

Formulation of carbon black-ionomer dispersions for thin film formation in fuel cells

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Particuology 2019年第3期17卷 7-21页

作者： eva Hoffmann Su Zhang Martin Thoma Cornelia Damm Wolfgang Peukert Institute of Particle Technology (LFG) Friedrich-Alexander-Universitat Erlangen-Niimberg (FAU) CauerstraJSe 4 D-91058 Erlangen Germany

The performance of proton exchange membrane fuel cells (PEMFC) is strongly determined by the structure and composition of the electrode *** interactions between the ionomer,carbon black particles,and solvent affect the suspension properties and thus the layer *** analyze the effect of the ionomer-to-carbon (I/C) weight ratio for two different types of carbon black on the suspension and layer *** branched carbon blacks with a high surface area tend to form less cracked *** less branched carbons can pack together more closely,a smaller pore size results in a larger capillary pressure during drying and thus more *** added ionomer adsorbs on the carbon particles and improves the colloidal stability of the carbon black *** carbon black aggregates are thus smaller,resulting in closer packing and thinner ***,the addition of the ionomer increases the critical coating thickness (CCT) of the layers because drying stresses are dissipated by the deformation of the ionomer,preventing crack *** optimum I/C weight ratio is identified for optimal layer formation and minimized crack formation.

关键词： Perfluorosulfonic acid (PFSA) ionomer Carbon black Layer formation Cracking Porosity

Melatonin:a multitasking indoleamine to modulate hippocampal neurogenesis

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Neural Regeneration Research 2023年第3期18卷 503-505页

作者： Alejandro Romero JoséÁngel Morales-García eva Ramos Department of Pharmacology and Toxicology Faculty of Veterinary MedicineComplutense University of Madrid Institute for Biomedical Research“A.Sols”(CSIC-UAM) Spanish Center for Networked Biomedical Research on Neurodegenerative Diseases(CIBERNED Department of Cellular Biology School of MedicineComplutense University of MadridMadridSpain

Neurodegeneration affects a large number of cell types including neurons,astrocytes or oligodendrocytes,and neural stem *** stem cells can generate new neuronal populations through proliferation,migration,and *** neurogenic potential may be a relevant factor to fight neurodegeneration and *** the last years,we can find growing evidence suggesting that melatonin may be a potential modulator of adult hippocampal *** lack of therapeutic strategies targeting neurogenesis led researchers to explore new *** preclinical studies with melatonin observed how melatonin can modulate and enhance molecular and signaling pathways involved in *** made a special focus on the connection between these modulation mechanisms and their implication in neurodegeneration,to summarize the current knowledge and highlight the therapeutic potential of melatonin.

关键词： adult hippocampal neurogenesis aging melatonin neural stem cell neurodegeneration neuroprotection signaling pathway therapeutic strategy

All Roads Lead to Auxin: Post-translational Regulation of Auxin Transport by Multiple Hormonal Pathways

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Plant Communications 2020年第3期1卷 1-19页

作者： Hana Semeradova Juan Carlos Montesinos eva Benkova Institute of Science and Technology Austria 3400 KlosterneuburgAustria

Auxin is a key hormonal regulator,that governs plant growth and development in concert with other hormonal *** unique feature of auxin is its polar,cell-to-cell transport that leads to the formation of local auxin maxima and gradients,which coordinate initiation and patterning of plant *** molecular machinery mediating polar auxin transport is one of the important points of interaction with other *** hormonal pathways converge at the regulation of auxin transport and form a regulatory network that integrates various developmental and environmental inputs to steer plant *** this review,we discuss recent advances in understanding the mechanisms that underlie regulation of polar auxin transport by multiple hormonal ***,we focus on the post-translational mechanisms that contribute to fine-tuning of the abundance and polarity of auxin transporters at the plasma membrane and thereby enable rapid modification of the auxin flow to coordinate plant growth and development.

关键词： plant hormones polar auxin transport(PAT) post-translational regulation trafficking PINs abiotic stress

Aerial pollutants on a pig farm in peri-urban Beijing,China

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International Journal of Agricultural and Biological Engineering 2013年第1期6卷 36-47页

作者： Roxana Mendoza Huaitalla eva Gallmann Liu Xuejun Eberhard Hartung Institute of Agricultural Engineering University of HohenheimStuttgart70599Germany College of Agricultural Resources and Environmental Sciences China Agricultural UniversityBeijing 100094China Institute of Agricultural Engineering Christian-Albrechts-University KielKiel24098Germany

The study was carried out to evaluate the airborne gases and suspended particulate matter concentrations in the pig barns of a commercial pig farm situated in the peri-urban area of Beijing,*** measurements followed the natural pig life-stages namely:gestation,farrowing,weaning,and *** order to accomplish these objectives,three different measurement devices were employed:(i)color diffusion tubes,(ii)a portable gas measuring device,and(iii)a dust measuring *** to the rotation of the devices in the different sampling places,the measurements were performed at different time periods during the months of the summer and winter season in *** pig farm had a capacity of 15000 pigs per year and the manurial system was identified as“gan qing fen”or dry cleaning of the *** main by-products generated by the farm were irrigation water and small-scale biogas *** dust concentrations were identified in the pig barns,especially during the feeding and manure cleaning events inside the farrowing and weaning barns with slatted *** dust ranged from 0 mg/m3 to 12.45 mg/m3,while the allowable dust ranged from 0 mg/m3 to 9.62 mg/*** concentration ranged from 0 ppm to 20 ppm(1 ppm=1 cm3/m3),and the carbon dioxide concentration ranged from 300 ppm to 8000 *** highest ammonia concentration was recorded in the fattening barn during the summer season,while the highest carbon dioxide concentration was reported in the weaning barn during the summer *** results of this study were similar to the results of studies performed on pig farms under natural and mechanical ventilation *** the other hand,the problems encountered during the gas measurements on the pig farm were directly related to the inadequate housing layout due to the obstruction of windows,fans and air channels for indoor ventilation,and thus the measurement devices faced harsh working ***,it is recommended that the housing system s

关键词： pig farm aerial pollutant barn China gases dust

Perspectives for delivery of therapeutics by extravasation of biodegradable microspheres in the brain

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Neural Regeneration Research 2024年第5期19卷 969-970页

作者： Anne-eva van der Wijk Ed VanBavel Amsterdam UMC location University of Amsterdam Department of Biomedical Engineering and PhysicsAmsterdamThe Netherlands Amsterdam Neuroscience Neurovascular Disorders ProgramAmsterdamThe Netherlands Amsterdam Cardiovascular Sciences Microcirculation ProgramAmsterdamThe Netherlands

Development of therapeutics for brain diseases has remained challenging,in particular due to the difficulty of passing the blood-brain *** a result,the current arsenal of therapeutics targeting the brain is limited to small,lipid-soluble drugs and there is a lack of options for treating neuroblastomas,Alzheimer’s disease,and many other devastating *** the advances in strategies for crossing the blood-brain barrier such as the use of nanoparticles(Hersh et al.,2022;Duan et al.,2023),such delivery systems have not yet reached clinical ***,novel platforms for the transport of therapeutics across the blood-brain barrier remain highly *** specifically holds for large molecules such as monoclonal antibodies and recombinant proteins,as well as nucleotide-based therapeutics and cell *** efforts in this field are increasing exponentially,with thousands of publications in the last few years.

关键词： therapeutics holds spite

A short climatology of black and brown carbon and their sources at a suburban site impacted by smoke in Brazil

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Journal of Environmental Sciences 2024年第2期136卷 498-511页

作者： Admir Creso Targino Patricia Krecl Gabriel Yoshikazu Oukawa eva Maria Mollinedo Graduate Program in Environmental Engineering Federal University of TechnologyAv.Pioneiros 3131LondrinaPR 86036-370Brazil Department of Environmental Engineering Federal University of TechnologyAv.Pioneiros 3131LondrinaPR 86036-370Brazil

Emissions from biomass burning challenge efforts to curb air pollution in cities downwind of fire-prone regions,as they contribute large amounts of brown carbon(Br C)and black carbon(BC)*** investigated the patterns of Br C and BC concentrations using Aethalometer data(atλ=370 and 880 nm,respectively)spanning four years at a site impacted by the outflow of *** data required to be post processed for the shadowing effect since,without correction,concentrations would be between 29%and 35%*** Br C concentrations were consistently higher than the BC concentrations,indicating the prevalence of aerosols from biomass *** results were supported by the Angstrom coefficient(A_(370/880)),with values predominantly larger than 1(mean±standard deviation:1.25±0.31).A_(370/880)values below 1 were more prevalent during the wet season,which suggests a contribution from fossil fuel *** observed sharp Br C and BC seasonal signals,with mean minimum concentrations of 0.40μg/m^(3)and 0.36μg/m^(3),respectively,in the wet season,and mean maximum concentrations of 2.05μg/m^(3)and 1.53μg/m^(3)in the dry *** largest concentrations were observed when northerly air masses moved over regions with a high density of fire *** burning of residential solid waste and industrial combustion caused extreme Br C and BC concentrations under favourable wind *** neither pollutant is included in any ambient air quality standards,our results suggest that transboundary smoke may hamper efforts to meet the World Health Organization guidelines for fine particles.

关键词： Light-absorbing carbonaceous matter Black carbon Wildfires Biomass burning Aethalometer

Environmental correlates of sedentary behaviors and physical activity in Chinese preschool children:A cross-sectional study

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Journal of Sport and Health Science 2022年第5期11卷 620-629页

作者： Congchao Lu Tong Shen Guowei Huang eva Corpeleijn School of Public Health Tianjin Medical UniversityTianjin 300070China Department of Epidemiology University Medical Center GroningenUniversity of GroningenGroningen9700 RBthe Netherlands Tianjin Key Laboratory of Environment Nutrition and Public HealthCenter for International Collaborative Research on EnvironmentNutrition and Public HealthTianjin 300070China Tianjin University Kindergarten Tianjin UniversityTianjin 300072China Department of Nutrition and Food Science School of Public HealthTianjin Medical UniversityTianjin 300070China

Objective:This cross-sectional study examined environmental correlates of sedentary behavior(SB) and physical activity(PA) in preschool children in the urban area of Tianjin,***:Data were collected from the Physical Activity and Health in Tianjin Chinese Children study,involving healthy children 3-6 years old and their *** all children(n=980),leisure-time SB(LTSB) and leisure-time PA(LTPA) were reported in min/day by *** a subgroup(n=134),overall sedentary time,light PA,and moderate-to-vigorous PA(MVP A) were objectively measured using ActiGraph accelerometry(>3 days,>10 h/day).Environmental correlates were collected using a questionnaire that included home and neighborhood characteristics(e.g.,traffic safety,presence of physical activity facilities) and children’s *** correlates were identified using linear regression ***:Multiple linear regression analysis showed that "having grandparents as primary caregivers"(βs and 95% confidence intervals(95%CIs)for overall sedentary time:29.7(2.1-57.2);LTSB(In):0.19(0.11-0.28)) and "having a television(for LTSB(In):0.13(0.00-0.25)) or computer(for LTSB(ln):0.13(0.03-0.23) in the child’ s bedroom" were both associated with higher ***, "having grandparents as primary caregivers" was associated with less MVPA(β(95%CI):-7.6(-14.1 to-1.2)),and "active commuting to school by walking" correlated with more MVPA(β(95%CI):9.8(2.2-17.4)).The path model showed that "more neighborhood PA facilities close to home" was indirectly related to higher LTPA(In),which was partly mediated by "outdoor play"(path coefficients(95%CI):0.005(0.002-0.008)) and "going to these facilities more often"(path coefficients(95%CI):0.013(0.008-0.01 8)).Traffic safety was not a ***:Family structure and media exposure in the home maybe important factors in shaping preschoolers’ PA *** environmental correlates could indirectly influence preschoolers’ LTPA through parental h

关键词： Active commuting Built environment Family structure Media exposure Traffic safety