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Observations of defect propagation in [100]-oriented opal-type photonic crystals

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Chinese physics B 2008年第4期17卷 1298-1304页

作者：金崇君 Richard M.De La Rue Nigel p.johnson Department of Electronics & Electrical Engineering University of Glasgow School of physics and Engineering Laboratory of Optoelectronic Materials and TechnologiesSun Yat-Sen University

Charged colloidal suspensions have been used as experimental models for the study of crystal nucleation. Here we propose that the technique of template-assisted colloidal self-assembly can be used to visualize the effects of defect propagation in atomic crystal films produced using epitaxial growth. Templates with periodic line defects were used to grow [100]-oriented three-dimensional photonic crystals by means of the template-assisted colloidal self-assembly method, aided by capillary and gravitational forces. The defect propagation in the [100]-oriented photonic crystal was observed using scanning electron microscopy, both at the surface of the crystal and on cleaved facets. This method is useful in the understanding of defect propagation in the growth of colloidal films on templates - and the same approach may also prove useful for the understanding of atomic crystal growth on substrates with defects. Additionally, the deliberate incorporation of line defects may prove valuable as a way of introducing waveguide channels into three-dimensional photonic crystals.

关键词： photonic crystal colloidal crystal self-assembly

Occupational heat stress induced health impacts:A cross-sectional study from South Indian working population

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Advances in Climate Change Research 2020年第1期11卷 31-39页

作者： Vidhya VENUGOpAL p.K.LATHA Rekha SHANMUGAM Manikandan KRISHNAMOORTHY p.iscilla johnson Faculty of public Health Sri Ramachandra Institute of Higher Education and ResearchChennai600116India Department of physiology Sri Ramachandra Institute of Higher Education and ResearchChennai600116India

Rising temperature and heat stress risks in the changing climate scenario might potentially affect workers globally,especially the ones with strenuous workload in tropical *** used a cross-sectional study design to profile the heat exposures of-1900 workers from eight industrial sectors using a Ques Temp Wet Bulb Globe Temperature(WBGT)monitor,quantified select heat-strain indicators viz.,rise in Core Body Temperature,Sweat Rate,and Urine Specific Gravity and evaluated the perceived health impacts of heat stress using a structured *** exposures(average WBGT:30.1±2.6℃)exceeded the Threshold Limit Value for 67%workers and was positively associated with the rise in Core Body Temperature>1℃ in 13%and elevated Urine Specific Gravity>1.020 in 9%***-related health concerns were reported by 86%workers,and the heat-exposed workers had 2.3 times higher odds of adverse health outcomes compared to unexposed workers(pposure to higher WBGT and adverse renal health among salt-pan workers were significantly associated(p=0.004),and steel workers had 9% prevalence of kidney *** presented clearly points to heat stress as a health and productivity risk factor that could have long-term and irreversible health ***-depth assessments are urgently needed to develop scientifically sound preventative interventions and protective labor policies to avert the adverse occupational health and productivity consequences for millions of workers globally,thereby aiding poverty reduction.

关键词： Climate change Occupational heat stress physiological heat strain Renal issues Dehydration Workload

Biodiversity and interactions of acidophiles:Key to understanding and optimizing microbial processing of ores and concentrates

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中国有色金属学会会刊：英文版 2008年第6期18卷 1367-1373页

作者： D.B.johnson School of Biological Sciences Bangor University

采矿公司为从低档矿石恢复贱、宝贵的金属，并且为重新调停变得逐渐地知道 microbiological 途径的潜力从操作和放弃的矿地点排干的酸的、充满金属的废水。生物系统出现很多环境并且(有时) 超越常规途径的节俭的优点尽管他们的申请是，... 详细信息

采矿公司为从低档矿石恢复贱、宝贵的金属，并且为重新调停变得逐渐地知道 microbiological 途径的潜力从操作和放弃的矿地点排干的酸的、充满金属的废水。生物系统出现很多环境并且(有时) 超越常规途径的节俭的优点尽管他们的申请是，例如热冶学，别处于每种状况拨出。矿物质用微生物处理为提取黄金，铜，铀和钴被利用了，并且当前的开发正在指向另外的贱金属。最近，我们 biomining 环境，并且微生物怎么与对方一起交往的微生物学的差异的知识和理解有大增加。从模仿了搅动的坦克和堆生物反应器系统的实验室实验的结果证明了微生物引起的协会比氧化矿物质的 acidophiles 的纯文化更柔韧，并且也趋于在 bioleaching 和氧化简历的矿石更有效并且专注。纸论述了性质的简明评论和涉及硫化物矿物质的氧化的微生物引起的协会的相互作用，并且这些怎么可能被改编在 biomining 操作遇见未来挑战。

关键词：嗜酸细胞生物采矿生物多样性微生物加工

Distilling physical origins of hardness in multi-principal element alloys directly from ensemble neural network models

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npj Computational Materials 2022年第1期8卷 1450-1460页

作者： D.Beniwal p.Singh S.Gupta M.J.Kramer D.D.johnson p.K.Ray Metallurgical&Materials Engineering Indian Institute of Technology RoparRupnagar140001PunjabIndia Ames Laboratory US Department of EnergyAmesIA50011USA Materials Science&Engineering Iowa State UniversityAmesIA50011USA

Despite a plethora of data being generated on the mechanical behavior of multi-principal element alloys,a systematic assessment remains inaccessible via Edisonian *** approach this challenge by considering the specific case of alloy hardness,and present a machine-learning framework that captures the essential physical features contributing to hardness and allows high-throughput exploration of multi-dimensional compositional *** model,tested on diverse datasets,was used to explore and successfully predict hardness in Al_(x)Ti_(y)(CrFeNi)_(1-x-y),Hf_(x)Co_(y)(CrFeNi)_(1-x-y)and Al_(x)(TiZrHf)_(1-x)systems supported by data from density-functional theory predicted phase stability and ordering *** experimental validation of hardness was done on *** selected systems pose diverse challenges due to the presence of ordering and clustering pairs,as well as vacancy-stabilized novel *** also present a detailed model analysis that integrates local partial-dependencies with a compositional-stimulus and model-response study to derive material-specific insights from the decision-making process.

关键词： alloys alloy element

Experimental Modelling of Transverse Oscillations in Aquaculture Netting parallel to the Flow – Sounds Baffling

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China Ocean Engineering 2015年第3期29卷 391-400页

作者： Andrew johnson Cheslav BALASH National Centre for Maritime Engineering and Hydrodynamics Australian Maritime CollegeUniversity of Tasmania Launceston

Numerous studies have been undertaken to improve the viability, durability and suitability of materials and methods used for aquaculture enclosures. While many of the previous studies considered macro-deformation of nets, there is a paucity of information on netting micro-deformation. When aquaculture pens are towed, industry operators have observed the motion described as ＂baffling＂ – the transverse oscillation of the net planes parallel and near parallel to the flow. The difficulty to observe and assess baffling motion in a controlled experimental environment is to sufficiently reproduce netting boundary conditions and the flow environment experienced at sea. The focus of the present study was to develop and assess experimental methods for visualisation and quantification of these transverse oscillations. Four netrig configurations with varied boundary conditions and model-netting properties were tested in a flume tank. While the Reynolds number was not equivalent to full-scale, usage of the pliable and fine mesh model netting that enabled baffling to develop at low flow velocities was deemed to be of a larger relevance to this initial study. Baffling was observed in the testing frame that constrained the net sheet on the leading edge, similarly to a flag attachment onto a pole. Baffling motion increased the hydrodynamic drag of the net by 35%–58% when compared to the previously developed formula for taut net sheets aligned parallel to the flow. Furthermore, it was found that the drag due to baffling decreased with the increasing velocity over the studied Reynolds numbers（below 200）; and the drag coefficient was non-linear for Reynolds numbers below 120. It is hypothesised that baffling motion is initially propagated by vortex shedding of the netting twine which causes the netting to oscillate; there after the restoring force causes unstable pressure differences on each side of the netting which excites the amplitude of the netting oscillations.

关键词： aquaculture pen baffling model net testing netting drag netting micro-deformation

Speciation:genomic sequence data and the biogeography of speciation

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National Science Review 2022年第12期9卷 13-14页

作者： Norman A.johnson Department of Biology University of Massachusetts–Amherst

Two papers in this issue show how the use of genomic sequence data can illuminate the biogeography of the speciation ***,I provide a backdrop to these studies,with a brief history of the use of markers and the biogeog... 详细信息

关键词： Speciation:genomic sequence data and the biogeography of speciation

Min-Max Theory for Cell Complexes

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Algebra Colloquium 2020年第3期27卷 447-454页

作者： Lacey johnson Kevin Knudson Department of Mathematics University of FloridaGainesvilleFL 32611USA

In the study of smooth functions on manifolds,min-max theory provides a mechanism for identifying critical values of a *** introduce a discretized version of this theory associated to a discrete Morse function on a(regular)cell *** applications we prove a discrete version of the mountain pass lemma and give an alternate proof of a discrete Lusternik-Schnirelmann theorem.

关键词： discrete Morse theory min-max theory

Content sensitivity based access control framework for Hadoop

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Digital Communications and Networks 2017年第4期3卷 213-225页

作者： Ashwin Kumar T.K. Hong Liu johnson p. Thomas Xiaofeh Hou Department of Computer Science Oklahoma State University Stillwater OK USA

Big data technologies have seen tremendous growth in recent years. They are widely used in both industry and academia. In spite of such exponential growth, these technologies lack adequate measures to protect data from misnse/abuse. Corporations that collect data from multiple sources are at risk of liabilities due to the exposure of sensitive information. In the current implementation of Hadoop, only file-level access control is feasible. providing users with the ability to access data based on the attlibutes in a dataset or the user＇s role is complicated because of the sheer volume and multiple formats （structured, unstructured and semi-structured） of data. In this paper, we propose an access control framework, which enforces access control policies dynamically based on the sensitivity of the data. This framework enforces access control policies by harnessing the data context, usage patterns and informat/on sensitivity. Information sensitivity changes over time with the addition and removal of datasets, which can lead to modifications in access control decisions. The proposed framework accommodates these changes. The proposed framework is automated to a large extent as the data itself determines the sensitivity with minimal user intervention. Our experimental results show that the proposed framework is capable of enforcing access control policies on non-multimedia datasets with minimal overhead.

关键词： Access control Data driven information sensitivity privacy Information value

Hippo signaling and epithelial cell plasticity in mammalian liver development, homeostasis, injury and disease

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Science China(Life Sciences) 2019年第12期62卷 1609-1616页

作者： Randy L.johnson Department of Cancer Biology University of Texas MD Anderson Cancer Center

A traditional view of cellular differentiation is unidirectional: progenitor cells adopt specific fates in response to environmental cues resulting in deployment of cell-specific gene expression programs and acquisition of unique differentiated cellular properties such as production of structural and functional proteins that define individual cell types. In both development and in tissue repair stem and progenitor cells are thought to both self-renew to maintain the pool of precursors and to expand to give rise to transient amplifying and differentiated cell types. Recently, however, it has become appreciated that differentiated cell types can be reprogrammed to adopt progenitor and stem cell properties. In the case of epithelial cells in the mammalian liver, hepatocytes and biliary epithelial cells there is a significant degree of plasticity between these lineages that has been implicated in mechanisms of tissue repair and in liver pathologies such as cancer. Recent studies have highlighted the role of Hippo signaling, an emerging growth control and tumor suppressor pathway, in regulating epithelial cell plasticity in the mammalian liver and in this review, the role of cellular plasticity and Hippo signaling in regulating normal and abnormal tissue responses in the mammalian liver will be discussed.

关键词： liver homeostasis plasticity regeneration cancer Hippo pathway