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Highly efficient silicon light emitting diodes produced by doping engineering

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Frontiers of Optoelectronics 2012年第1期5卷 7-12页

作者： Jiaming SUN M.HELM W.SKORUPA b.SCHMIDT A.MVCKLICH Key Laboratory of Weak Light Nonlinear Photonics Ministry of Education Nankai UniversityTianjin 300071China Institute of Ion beam Physics and Materials Research Helmholtz-Zentrum Dresden-RossendorfDresden 01314Germany

This paper reviews our recent progress on silicon （Si） pn junction light emitting diodes with locally doping engineered carrier potentials. boron implanted Si diodes with dislocation loops have electroluminescence （EL） quantum efficiency up to 0.12%, which is two orders of magnitude higher than those without dislocations. boron gettering along the strained dislocation lines produces locally p-type spike doping at the dislocations, which have potential wells for bounding spatially indirect excitons. Thermal dissociation of the bound excitons releases free carriers, leading to an anomalous increase of the band to band luminescence with increasing tempera- ture. Si light emitting diodes with external quantum efficiency of 0.2% have been also demonstrated by implementation of pnpn modulation doping arrays.

关键词： silicon (Si) light emitting diodes dopingengineering dislocation modulation doping

Achieving superior mechanical properties of selective laser melted AlSi10Mg via direct aging treatment

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Journal of Materials Science & Technology 2022年第13期108卷 226-235页

作者： H.Zhang Y.Wang J.J.Wang D.R.Ni D.Wang b.L.Xiao Z.Y.Ma Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China College of Materials Science and Engineering Shenyang Aerospace University37 Daoyi South AvenueShenyang 110136China

For additive manufactured aluminum alloys,the inferior mechanical properties along the building direction have been a serious *** this study,an optimized heat treatment was developed as a simple and effective *** effects of direct aging on microstructure and mechanical properties along the building direction of AlSi10Mg samples produced via selective laser melting(SLM)were *** results showed that,compared with the conventional heat treatment at elevated temperatures,direct aging at temperatures of 130-190℃ could retain the fine grain microstructure of SLM samples and promote further precipitation of Si phase,however,the growth of pores occurred during direct *** increasing aging temperature,while finer cell structures were obtained,more and larger pores were developed,resulting in decreased density of the *** types of pore formation mechanisms were *** the balance between the refinement of cell structure and the growth of pores,aging at 130℃ was determined as the optimized heat treatment for SLM AlSi10Mg *** tensile strength along the building direction of the 130℃ aged sample was increased from 403 MPa to 451 MPa,with relatively high elongation of 6.5%.

关键词： Additive manufacturing Selective laser melting AlSi10Mg alloy,Heat treatment

biomarkers of hypoxic-ischemic encephalopathy:a systematic review

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World Journal of Pediatrics 2023年第6期19卷 505-548页

作者： Ines Caramelo Margarida Coelho Miguel Rosado Carla M.P.Cardoso Alexandra Dinis Carlos b.Duarte Mario Graos bruno Manadas CNC-Center for Neuroscience and Cell biology University of Coimbra3004‑504 CoimbraPortugal PhD Programme in Experimental biology and biomedicine Institute for Interdisciplinary Research(IIIUC)University of CoimbraCasa Costa Alemão3030‑789 CoimbraPortugal Chemistry Department Faculty of Sciences and TechnologyUniversity of Coimbra3004‑535 CoimbraPortugal Stemlab SA 3060‑197 CantanhedePortugal Pediatric Intensive Care Unit Hospital PediátricoCentro Hospitalar E Universitário de Coimbra3000‑075 CoimbraPortugal Department of Life Sciences University of Coimbra3001‑401 CoimbraPortugal biocant Technology Transfer Association3060‑197 CantanhedePortugal Institute for Interdisciplinary Research University of Coimbra(IIIUC)3030‑789 CoimbraPortugal

background Current diagnostic criteria for hypoxic–ischemic encephalopathy in the early hours lack objective measurement ***,this systematic review aims to identify putative molecules that can be used in diagnosis in daily clinical practice(PROSPERO ID:CRD42021272610).Data sources Searches were performed in PubMed,Web of Science,and Science Direct databases until November *** original papers analyzing samples from newborns>36 weeks that met at least two American College of Obstetricians and Gynecologists diagnostic criteria and/or imaging evidence of cerebral damage were *** was assessed by the Newcastle–Ottawa *** search and data extraction were verified by two authors *** From 373 papers,30 met the inclusion *** from samples collected in the first 72 hours were extracted,and increased serum levels of neuron-specific enolase and S100-calcium-binding protein-b were associated with a worse prognosis in newborns that suffered an episode of perinatal *** addition,the levels of glial fibrillary acidic protein,ubiquitin carboxyl terminal hydrolase isozyme-L1,glutamic pyruvic transaminase-2,lactate,and glucose were elevated in newborns diagnosed with hypoxic–ischemic ***,pathway analysis revealed insulin-like growth factor signaling and alanine,aspartate and glutamate metabolism to be involved in the early molecular response to *** Neuron-specific enolase and S100-calcium-binding protein-b are potential biomarkers,since they are correlated with an unfavorable outcome of hypoxic-ischemic encephalopathy ***,more studies are required to determine the sensitivity and specificity of this approach to be validated for clinical practice.

关键词： biomarker Hypoxic-ischemic encephalopathy Neonatal brain injury Newborn Neuron-specific enolase S100-calcium-binding protein-b

THE FUTURE OF SCIENTIFIC JOURNALS

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编辑学报 2000年第2期12卷 120-124页

作者： DONOV.,b

科学论文肯定还将长期存在，因为如果只进行研究而不发表结果，投入的时间和金钱就不能产生效益，不少人把科学杂志仅仅看作是论文的合订本，这样科学杂志是否还将长期存在，便不象科学论文那样肯定，然而，一项由学术与专业学会出版商... 详细信息

科学论文肯定还将长期存在，因为如果只进行研究而不发表结果，投入的时间和金钱就不能产生效益，不少人把科学杂志仅仅看作是论文的合订本，这样科学杂志是否还将长期存在，便不象科学论文那样肯定，然而，一项由学术与专业学会出版商协会（Association of Learned and Professional Society Publishers,ALPSP）完成的研究表明，科学论文的潜在作者十分看重期刊的声望，影响因子和同行评议的质量，优秀的期刊还汇聚有关领域的研究兴趣，推进着学科的进步，日趋明郎的是，电子数据库或者电子期刊将难以替代印刷版期刊，这不仅因为作者喜见自己的作品刊在高质量的期刊上，而且还因为电子产品在长期保存方面的许多问题，这些以及有关细节将予讨论。

关键词：科学杂志科学论文期刊发展学科发展印刷版期刊电子期刊

FERONIA Is a Key Modulator of brassinosteroid and Ethylene Responsiveness in Arabidopsis Hypocotyls

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Molecular Plant 2010年第3期3卷 626-640页

作者： Stephen D. Deslauriers Paul b. Larsen Department of biochemistry University of California-Riverside Riverside CA 92521 USA

Ethylene signaling is a complex pathway that has been intensively analyzed partly due to its importance to the manifestation of horticultural phenomena, including fruit ripening and tissue senescence. In order to further our un- derstanding of how this pathway is regulated, a screen for Arabidopsis mutants with increased ethylene response was conducted. From this, a mutant was identified as having a dark-grown hypocotyl that is indistinguishable from Col-0 wt in the presence of the ethylene perception inhibitor AgNO3, yet has extreme responsiveness to even low levels of ethylene. Map-based cloning of the mutation revealed a T-DNA insertion in the coding sequence of the receptor-like kinase FERONIA, which is required for normal pollen tube reception and cell elongation in a currently unknown capacity. In contrast to a previous report, analysis of our feronia knockout mutant shows it also has altered responsiveness to brassinosteroids, with etiolated fer-2 seedlings being partially brassinosteroid insensitive with regard to promotion of hypocotyl elonga- tion. Our results indicate that FERONIA-dependent brassinosteroid response serves to antagonize the effect of ethylene on hypocotyl growth of etiolated seedlings, with loss of proper brassinosteroid signaling disrupting this balance and leading to a greater impact of ethylene on hypocotyl shortening.

关键词： FERONIA ethylene brassinosteroid triple response hypocotyl Arabidopsis.

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多巴胺能系统

Promoting remyelination for the treatment of multiple sclerosis:opportunities and challenges

1989年

作者： b.Halasz

本书著者原题无汉译名:本书内容包括“神经内分泌学引论”、“脑和垂体的多巴胺能系统”以及“外周多巴胺的作用”三部分。

关键词：医药、卫生基础医学人体生理学

来源：汇雅图书（南通市图书馆... 评论

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Neuroscience bulletin 2013年第2期29卷 144-154页

作者： Yueting Zhang Taylor b.Guo Hongtao Lu Neuroimmunology Discovery Performance Unit GlaxoSmithKline Research and Development Center

Multiple sclerosis （MS） is a chronic and devastating autoimmune demyelinating disease of the central nervous system. With the increased understanding of the pathophysiology of this disease in the past two decades, many disease-modifying therapies that primarily target adaptive immunity have been shown to prevent exacerbations and new lesions in patients with relapsing-remitting MS. However, these therapies only have limited efficacy on the progression of disability. Increasing evidence has pointed to innate immunity, axonal damage and neuronal loss as important contributors to disease progression. Remyelination of denuded axons is considered an effective way to protect neurons from damage and to restore neuronal function. The identification of several key molecules and pathways controlling the differentiation of oligodendrocyte progenitor cells and myelination has yielded clues for the development of drug candidates that directly target remyelination and neuroprotection. The long-term efficacy of this strategy remains to be evaluated in clinical trials. Here, we provide an overview of current and emerging therapeutic concepts, with a focus on the opportunities and challenges for the remyelination approach to the treatment of MS.

关键词： multiple sclerosis myelination neurodegeneration oligodendrocytes disease progression disease modifying therapy drug target animal models

Ontogeny of rat chondrocyte proliferation:studies in embryo,adult and osteoarthritic (OA) cartilage

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Cell Research 2005年第2期15卷 99-104页

作者： Madaí A GóMEZ-CAMARILLO,Juan b.KOURI Departamento de Patología Experimental Centro de Investigación y de Estudios Avanzados. Instituto Politécnico Nacional(CINVESTAV-IPN) México.Centro de Investigación en Ciencias biológicas Universidad Autónoma de Tlaxcala México. Departamento de Patología Experimental Centro de Investigación y de Estudios Avanzados. Instituto Politécnico Nacional(CINVESTAV-IPN) México

The aim of this work was to study the ontogeny of chondrocyte cell division using embryo, adult and osteoarthritic(OA) cartilage. We searched for mitosis phases and performed a comparative evaluation of mitotic index, basic fibro-blast growth factor b (FGFb), transforming growth factor β1 (TGF-β1) receptors, cyclin dependent kinase (CDK1)and Cyclin-b expression in fetal, neonate, 3, 5, 8 weeks old rats and experimental OA. Our results showed that mitosisphases were observed in all normal cartilage studied, although, we found a decrease in mitotic index in relation to tissuedevelopment. No mitosis was detected in OA cartilage. We also found a statistical significant reduction in cell number inOA cartilage, compared with the normal tissue. Furthermore, FGFb and TGF-β1 receptors diminished in relation totissue development, and were very scarce in experimental OA. Western blot assays showed CDK-1 expression in allcases, including human-OA cartilage. Similar results were observed for Cyclin-b, except for 8 weeks, when it was notexpressed. Our results suggest that cell division seems to be scarce, if not absent within the OA cartilage ***, the existence of factors essential for cell division leaves open the question concerning chondrocyteproliferation in OA cartilage, which is likely to be present in the early stages of the disease.

关键词： proliferation chondrocytes mitotic index growth factors.

The impact of age structure and vaccine prioritization on COVID-19 in West Africa

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Infectious Disease Modelling 2022年第4期7卷 709-727页

作者： Hemaho b.Taboe Michael Asare-baah Afsana Yesmin Calistus N.Ngonghala Department of Mathematics University of FloridaGainesvilleFL32611USA Laboratoire de biomathematiques et d’Estimations Forestieres University of Abomey-CalaviCotonouBenin Department of Epidemiology University of Florida2004 Mowry RoadGainesvilleFL32610USA Emerging Pathogens Institute University of FloridaGainesvilleFL32610USA

The ongoing COVID-19 pandemic has been a major global health challenge since its emergence in *** to early predictions that sub-Saharan Africa(SSA)would bear a disproportionate share of the burden of COVID-19 due to the region's vulnerability to other infectious diseases,weak healthcare systems,and socioeconomic conditions,the pandemic's effects in SSA have been very mild in comparison to other ***,the number of cases,hospitalizations,and disease-induced deaths in SSA remain low,despite the loose implementation of non-pharmaceutical interventions(NPIs)and the low availability and administration of *** explanations for this low burden include epidemiological disparities,under-reporting(due to limited testing),climatic factors,population structure,and government policy *** this study,we formulate a model framework consisting of a basic model(in which only susceptible individuals are vaccinated),a vaccine-structured model,and a hybrid vaccine-age-structured model to assess the dynamics of COVID-19 in West Africa(WA).The framework is trained with a portion of the confirmed daily COVID-19 case data for 16 West African countries,validated with the remaining portion of the data,and used to(i)assess the effect of age structure on the incidence of COVID-19 in WA,(ii)evaluate the impact of vaccination and vaccine prioritization based on age brackets on the burden of COVID-19 in the sub-region,and(iii)explore plausible reasons for the low burden of COVID-19 in WA compared to other parts of the *** of the model parameters and global sensitivity analysis show that asymptomatic youths are the primary drivers of the pandemic in ***,the basic and control reproduction numbers of the hybrid vaccine-age-structured model are smaller than those of the other two models indicating that the disease burden is overestimated in the models which do not account for *** result is confirmed through the vaccine-d

关键词： Vaccine prioritization SARS-CoV-2 Omicron variant AVAT Reproduction number Herd immunity