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Reduced Annealing Time and Enhanced Magnetocaloric Effect of La(Fe,Al)13 Alloy by La-nonstoichiometry and Si-doping

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Acta Metallurgica Sinica(English Letters) 2020年第11期33卷 1535-1542页

作者： Liang Yang Jun Li defang Tu joel C.J.Strickland Qiaodan Hu Hongbiao Dong Jianguo Li School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Engineering University of LeicesterLeicester LE17RHUK Collaborative Innovation Center for Advanced Ship and deep-Sea Exploration Shanghai Jiao Tong UniversityShanghai 200240China

LaFe13-x Mx(M=Si,Al)alloys are promising for use in magnetic ***,they require long annealing time(30 days)in order to optimize the magnetocaloric *** has shown that the addition of extra La in off-stoichiometric alloys can greatly shorten the annealing ***,the purpose of this study is to investigate the influence of the extra addition of La on the annealing properties of a new off-stoichiometric La1.7Fe11.6Al1.4-xSix(x=0,0.1,0.4)*** was demonstrated that after a 36 h annealing time,a large volume fraction of 1:13 magnetocaloric phase was obtained for all *** microstructural analysis of the off-stoichiometric La1.7Fe11.6Al1.4-xSix alloys revealed a facet-like grain *** La1.7Fe11.6Al1.4 and La1.7Fe11.6Al1Si0.4 alloys were shown to contain large 1:13 phase precipitates separated in a La-rich matrix,while the La1.7Fe11.6Al1.3Si0.1 alloy had a continuous 1:13 phase matrix with a fine dispersion of La-rich precipitates *** the magnetic field varied between 0 and 2 T,the corresponding magnetic entropy change and relative cooling capacity for the La1.7Fe11.6Al1.3Si0.1 specimen were determined as 4.58 J/kg K and 173.6 J/kg,*** importantly,the La1.7Fe11.6Al1.3Si0.1 alloy displayed only a slight volume change when the meta-magnetic phase transition occurred,which is promising for cyclic use.

关键词： Solidifi cation Magnetic properties Heat treatment Microstructure Functional alloys

Tree diversity and nectar composition affect arthropod visitors on extrafloral nectaries in a diversity experiment

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Journal of Plant Ecology 2017年第1期10卷 201-212页

作者： Michael Staab joel Methorst Jan Peters Nico Blüthgen Alexandra-Maria Klein Faculty of Environment and Natural Resources Chair of Nature Conservation and Landscape EcologyUniversity of FreiburgTennenbacher Straße 479106 FreiburgGermany Institute of Ecology Leuphana University of LüneburgScharnhorststraße 121335 LüneburgGermany Ecological Network Group Department of BiologyTechnical University DarmstadtSchnittspahnstraße 1064287 DarmstadtGermany

Aims Plants with extrafloral nectaries(EFNs)are common in tropical and subtropical habitats and,despite many other arthropods also forage for EFN,most studies solely focused on the defense mutualisms between EFN plants and *** study aims at a quantitative assessment of the entire arthropod community that visits EFN trees to compare visitor communities between different tree species to disentangle the mechanisms that may drive EFN visitor community *** also test for tree diversity effects on EFN visitors,as it is unknown if local tree species richness relates to the abundance and species richness of arthropods foraging for *** We sampled EFN-visiting arthropods in the experimental tree species richness gradient of the BEF-China Experiment,the currently largest forest diversity experiment in the world,and tested if tree species richness affects EFN visitors and if visitor community composition differs between EFN tree *** a second step,we analyzed the EFN of Ailanthus altissima and Triadica cochinchinensis,the two EFN tree species with highest visitor abundance,for sugars and amino acids(AA)to test if tree species-specific differences in nectar chemistry translate to differing visitor ***,we conducted a choice experiment using different artificial nectar solutions to test if nectar quality affects foraging decisions of ants,the most frequent EFN visitors in our study *** Findings EFN trees in young successional forests in subtropical South-East China are visited by a diverse assemblage of arthropods including ants,beetles,flies,and *** ants accounted for about 75%of all individuals,non-ant visitors were by far more species *** abundance and species richness declined with increasing tree species richness,suggesting a resource dilution effect,because plots with more tree species had proportionally less EFN tree individuals and thus lower nectar *** altissima and ***

关键词： amino acids BEF-China choice experiment formicidae HPLC chemical analysis

Prospects for Tin-Containing Halide Perovskite Photovoltaics

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Precision Chemistry 2023年第2期1卷 69-82页

作者： Shuaifeng Hu joel A.Smith Henry J.Snaith Atsushi Wakamiya the department of Chemistry Graduate School of Science of Kyoto University in Japan the department of Physics University of OxfordOxfordUK the Institute for Chemical Research of Kyoto University in Japan

Tin-containing metal halide perovskites have enormous potential as photovoltaics,both in narrow band gap mixed tin−lead materials for all-perovskite tandems and for lead-free *** introduction of Sn(II),however,has significant effects on the solution chemistry,crystallization,defect states,and other material properties in halide *** this perspective,we summarize the main hurdles for tin-containing perovskites and highlight successful attempts made by the community to overcome *** discuss important research directions for the development of these materials and propose some approaches to achieve a unified understanding of Sn *** particularly focus on the discussion of charge carrier dynamics and nonradiative losses at the interfaces between perovskite and charge extraction layers in p-i-n *** hope these insights will aid the community to accelerate the development of high-performance,stable single-junction tincontaining perovskite solar cells and all-perovskite tandems.

关键词： solar cell perovskite tin crystallization surface chemistry defect passivation carrier dynamic

Is infliximab safe to use while breastfeeding?

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World Journal of Gastroenterology 2008年第19期14卷 3085-3087页

作者： joel Z Stengel Hays L ArnoldJ Brooke Army Medical Cente3851 Roger Brooke Drive

Inflammatory bowel disease (IBD) often affects women around the age of conception and pregnancy. Most drugs used to treat IBD are safe in pregnancy, but physicians must consider the clinical implications of certain treatment regimens in young, fertile females. We report an informative case of a pregnant patient with IBD who underwent treatment with infliximab during her pregnancy and while nursing her infant. Serum and breast milk infliximab levels were monitored throughout this time period. This case report suggests that targeted monoclonal antibodies and other biologic agents can be used with caution in pregnant and breastfeeding patients.

关键词： Inflammatory bowel disease Ulcerativecolitis Crohn's disease Pregnancy Breast-feeding Monoclonal antibodies

Effects of Eccentric Pre-loading on Concentric Vertical Jump Performance in young Female Athletes

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Journal of Science in Sport and Exercise 2021年第1期3卷 98-106页

作者： Zachary M.Gillen Marni E.Shoemaker Nicholas A.Bohannon Sydney M.Gibson joel T.Cramer department of Kinesiology Mississippi State University236 McCarthy GymnasiumStarkvilleMS 39762USA College of Health Sciences The University of Texas at El PasoEl PasoTX 79968USA College of Medicine University of Nebraska Medical CenterOmahaNE 68198USA department of Nutrition&Health Sciences University of Nebraska-LincolnLincolnNE 68583USA

Purpose This study examined changes in vertical jump performance with progressively greater eccentric pre-loading in relation to growth and development in young female *** Twenty young female athletes ranging from 9 to 17 years old performed the following vertical jumps in random order:static jumps(SJs),counter-movement jumps(CMJs),and drop jumps(DJs)from drop heights of 20,30,and 40 cm(DJ20,DJ30,and DJ40,respectively).Measurements included peak force(PF),peak rate of force development(RFD),peak power(PP),eccentric impulse(ECC),and concentric impulse(CON).Measurements of growth included age,maturity offset,height,body mass,fat-free mass,and thigh muscle cross-sectional area(CSA).Results PF increased from the SJ-DJ20(Pdecreased from CMJ-DJ20(Pyoung females produced greater power during the CMJ than SJ,but equivalent power from the CMJ-DJ40,despite increases in ***,ΔCMJ-SJ was not related to CSA,which suggests other underlying mechanisms affect stretch-shortening cycle utilization in young female athletes.

关键词： Stretch-shortening cycle Youth Ground reaction force Kinetics

The impact of local U.S. tobacco policies on youth tobacco use: a critical review

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Open Journal of Preventive Medicine 2011年第2期1卷 34-43页

作者： Karen B Friend Sharon Lipper-Kreda joel Grube decision Sciences Institute Pacific Institute for Research and Evaluation Pawtucket Rhode Island.

Tobacco use continues to be the leading preventable cause of premature death in the United States, killing over 430,000 people annually. To-bacco initiation and use among youth remains a significant public health concern. despite declines in U.S. youth tobacco use in recent years, state and national survey results are still cause for alarm. Although traditional school-based curricular programs are the most common strategy to prevent or reduce youth tobacco use, their effectiveness may be limited because young people are immersed in a broader social context in which tobacco is readily available. Environmental strategies change this social context by focusing on policy, enforcement, and media. A compelling body of evidence suggests that interventions at the state and federal levels can, when implemented in combination, reduce youth tobacco use. The impact of policies implemented at the local levels is less well understood and effects of environmental strategies on smokeless tobacco consumption have been largely ignored. The purpose of this paper is to review the literature on environmental strategies implemented at the local level on youth use of both cigarettes and smokeless tobacco. We highlight results of the extant *-literature, hypothesize possible effects where research is lacking, and suggest where future studies might be warranted.

关键词： Tobacco Youth Environmental Strategies Local Policies

High-throughput calculations of charged point defect properties with semi-local density functional theory— performance benchmarks for materials screening applications

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npj Computational Materials 2023年第1期9卷 1628-1639页

作者： Danny Broberg Kyle Bystrom Shivani Srivastava Diana Dahliah Benjamin A.D.Williamson Leigh Weston David O.Scanlon Gian-Marco Rignanese Shyam Dwaraknath joel Varley Kristin A.Persson Mark Asta Geoffroy Hautier Materials Sciences Division Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA 94720USA department of Materials Science and Engineering University of CaliforniaBerkeleyCA 94720USA John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMA 02138USA department of Physics An-Najah National UniversityNablusPalestine Institute of Condensed Matter and Nanosciences UniversitéCatholique de LouvainChemin desÉtoiles 8B-1348 Louvain-la-NeuveBelgium department of Materials Science and Engineering NTNU Norwegian University of Science and TechnologyTrondheimNorway Energy Technologies Area Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA 94720USA department of Chemistry University College London20 Gordon StreetLondon WC1H 0AJUK Thomas young Centre University College LondonGower StreetLondon WC1E 6BTUK Diamond Light Source Ltd. Diamond HouseHarwell Science and Innovation CampusDidcotOxfordshire OX110DEUK Lawrence Livermore National Laboratory LivermoreCA 94550USA Molecular Foundry Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA 94720USA Thayer School of Engineering Dartmouth CollegeHanoverNH 03755USA

Calculations of point defect energetics with density Functional Theory(DFT)can provide valuable insight into several optoelectronic,thermodynamic,and kinetic *** calculations commonly use methods ranging from semi-local functionals with a-posteriori corrections to more computationally intensive hybrid functional *** applications of DFT-based high-throughput computation for data-driven materials discovery,point defect properties are of interest,yet are currently excluded from available materials *** work presents a benchmark analysis of automated,semi-local point defect calculations with a-posteriori corrections,compared to 245“gold standard”hybrid calculations previously *** consider three different a-posteriori correction sets implemented in an automated workflow,and evaluate the qualitative and quantitative differences among four different categories of defect information:thermodynamic transition levels,formation energies,Fermi levels,and dopability *** highlight qualitative information that can be extracted from high-throughput calculations based on semi-local DFT methods,while also demonstrating the limits of quantitative accuracy.

关键词： properties defect correction

A Flat Sagittal Spinal Alignment Is Common among young Patients with Lumbar Disc Herniation

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Open Journal of Orthopedics 2016年第9期6卷 294-304页

作者： Olof Thoreson joel Beck Klas Halldin Helena Brisby Adad Baranto department of Orthopaedics Institute of Clinical Sciences at Sahlgrenska Academy University of Gothenburg and Sahlgrenska University Hospital Gothenburg Sweden

Background: Recent studies suggest a correlation between spinal sagittal alignment and different types of lumbar pathologies due to different load patterns on the lumbar spine. The main objective of this study was to investigate the preoperative spinal sagittal alignment in young patients (Methods: Information regarding preoperative clinical examinations was collected from the patient medical charts. Preoperative MRI examinations were used to classify lumbar types according to four sagittal spinal alignment groups (1: a long thoracic kyphosis, 2: a flat back, 3: a normal spine and 4: an increased thoracic kyphosis). Other MRI findings were also noted. Classification of lumbar types was performed independently by three spine surgeons. To compare two sample proportions the 2-sample z-test was performed. Results: The distribution of lumbar curve types was: Type 1, 17% (9 patients);Type 2, 62% (33 patients);Type 3, 17% (9 patients) and Type 4, 4% (2 patients). The distribution of operated levels was: L3 - L4, 2% (1 patient);L4 - L5, 47% (25 patients);L5 - S1, 42% (22 patients) and L4 - L5 + L5 - S1, 9% (5 patients). Conclusions: A majority of the young patients (62%) that underwent surgery due to herniated disc in the lumbar spine were classified as Type 2 indicating a flat back. Future studies are needed to increase the knowledge about spinopelvic sagittal alignment and the correlation to spinal pathologies.

关键词： Intervertebral Disc Displacement Sagittal Alignment Spine Surgery young Adult

A one-step,tunable method of selective reactive sputter deposition as a wrinkling approach for silver/polydimethylsiloxane for electrically conductive pliable surfaces

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Microsystems & Nanoengineering 2022年第4期8卷 221-231页

作者： joel Y.Y.Loh Ali Zeineddine Moein Shayegannia Robyn McNeil Liam McRae Nazir P.Kherani department of Electrical and Computing Engineering University of TorontoTorontoON M5S 3G4Canada department of Material Science and Engineering University of TorontoTorontoON M5S 3E4Canada

The wrinkle period and morphology of a metal thin film on an elastic substrate is typically controlled by modifying the substrate before carrying out additional metal deposition ***,we show that a simultaneously selective and reactive sputtering plasma that modifies the surface of a polydimethylsiloxane(PDMS)substrate while not reacting with the metal during the deposition process decreases the wrinkle wavelength and induces additional wrinkling components and features such as ripples or *** selective reaction of the nitrogen plasma with PDMS functionalizes the siloxane surface into silicon *** hardens the immediate surface of PDMS,with a quadratic increase in the young’s modulus as a function of the sputtering flow *** increase in the critical strain mismatch and the corresponding presence of folds in the nitrogen-modified wrinkled silver film form a suitable plasmonic platform for surface-enhanced Raman spectroscopy(SERS),yielding an enhancement factor of 4.8×105 for detecting *** enhancement is linked to the emergence of electromagnetic hotspots from surface plasmon polariton coupling between the folds/wrinkles,which in turn enables the detection of low concentrations of organics using ***,when strained,the nitrogen-modified wrinkles enhance electrical conductivity by a factor of 12 compared with unmodified ***,the optical properties of the substrate can be tuned by altering the N2 *** simple addition of nonreactive nitrogen to silver sputtering enables simultaneous PDMS hardening and growth of the silver film and together provide a new avenue for tuning wrinkling parameters and enhancing the electrical conductivity of pliable surfaces.

关键词： silver reactive film