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Electrically pumped metallic and plasmonic nanolasers

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Chinese Physics B 2018年第11期27卷 158-166页

作者： Martin T hill School of Electrical Electronic and Computer Engineering The University of Western Australia

In recent years, there have been a significant number of demonstrations of small metallic and plasmonic lasers. The vast majority of these demonstrations have been for optically pumped devices. Electrically pumped devices are advantageous for applications and could demonstrate concepts not amenable for optical pumping. However, there have been relatively few demonstrations of electrically pumped small metal cavity lasers. This lack of results is due to the following reasons： there are limited types of electrically pumped gain media available; there is a significantly greater level of complexity required in the fabrication of electrically pumped devices; finally, the required components for electrical pumping restrict cavity design options and furthermore make it intrinsically more difficult to achieve lasing. This review looks at the motivation for electrically pumped nanolasers, the key issues that need addressing for them to be realized, the results that have been achieved so far including devices where lasing has not been achieved, and potential new directions that could be pursued.

关键词： semiconductor lasers laser diode microcavity and microdisk laser integrated optics

Diversification of the rAB Guanosine Triphosphatase Family in Dicots and Monocots

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Journal of Integrative Plant Biology 2007年第8期49卷 1129-1141页

作者： Jiaming Zhang Daniel r. hill Anne W. Sylvester State Key Biotechnology Laboratory for Tropical Crops Institute of Tropical Bioscience and Biotechnology Chinese Academy of Tropical Agricultural Sciences Haikou 571101 China Department of Molecular Biology 3994 1000 East University Ave. University of Wyoming Laramie Wyoming 82071 USA

rAB guanosine triphosphatases （GTPases） are key regulators of vesicle trafficking and are essential to the growth and development of all eukaryotic cells. During evolution, the rAB family has expanded in different patterns to facilitate distinct cellular, developmental and physiological adaptations. Yeast has only 11 family members, whereas mammalian rABs have expanded to 18 rAB subfamilies. Plant rABs have diversified primarily by duplicating members within a single subfamily. Plant rABs are divided into eight subfamilies, corresponding to mammalian rAB1, rAB2, rAB5, rAB6, rAB7, rAB8, rAB11 and rAB18. Functional diversification of these is exemplified by the rAB1 ls, orthologs of which are partitioned into unique cell compartments in plants where they function to transport vesicles during localized tip growth. Similarly, the rAB2 family in grasses is likely involved in vesicle secretion associated with wall expansion, as determined by analysis of over-expression mutants. We propose that dicots and monocots have also diverged in their rAB profiles to accommodate unique cellular functions between the two groups. Here we present a bioinformatics analysis comparing the rAB sub-families of rice, maize and Arabidopsis. These results will guide future functional studies to test for the role of diversification of subfamilies unique to monocots compared to dicots.

关键词： dicot GTP binding protein monocot phylogenetic analysis rAB guanosine triphosphatase

Investigating the raveling test for full-depth reclamation

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Frontiers of Structural and Civil Engineering 2018年第2期12卷 222-226页

作者： robert hill Andrew BrAHAM Department of Civil Engineering University of Arkansas Fayetteville AR 72701 USA

Full-Depth reclamation （FDr） is a sustainable method of building pavement structure compared to more traditional rehabilitation methods. Traffic is generally returned to an FDr project before a surface course is applied, as water in the FDr needs time to evaporate from the structure. This should not be done too quickly or raveling occurs. Currently, there is no test to quantify the timing of return to traffic. In this study, the ＂raveling test of cold mixed bituminous emulsion samples＂（ASTM D7196） was used to compare asphalt emulsion and asphalt foam FDr. Asphalt emulsion samples were cured at ambient and 40℃ temperatures, while asphalt foam samples were cured at ambient temperatures. raveling test data was collected from 0 to 48 hours of curing, however, samples were often not able to withstand fifteen minutes of testing. Therefore, the ＂time lasted＂（the time the raveling head loses contact with the surface of the sample） was recorded. In general, the asphalt emulsion samples that were cured in the oven at 40℃ had a longer time lasted and showed higher potential for determination of return to traffic. In addition, the asphalt emulsion samples had a longer time lasted than the asphalt foam samples at ambient temperatures.

关键词： raveling full depth reclamation

Clearance angle and evolution of depth of cut in actuated disc cutting

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Journal of rock Mechanics and Geotechnical Engineering 2019年第3期11卷 644-658页

作者： Sevda Dehkhoda Bryce hill CSIrO Minerals resources Queensland Centre for Advanced Technologies

This paper investigates the effect of cutter clearance angle on variation of depth of cut and cutting process with an actuated disc cutting(ADC).ADC is a cyclic cutting method with two main characteristics:(i)a disk-shape cutter is used to attack the rock in an undercutting mechanism;and(ii)the cutter is dynamically actuated as it is moved across the ***,the cutting process of such system is periodic,each recurrence known as actuation *** first ADC model,developed in 2016,represented an idealization of the technology with a flat disc cutter,where no clearance angle was *** evolution of the contact between the disc and the rock was,therefore,computed only on horizontal x-y plane,ignoring the effect of normal component of the force acting on *** article reports on a study that incorporates the cutter inclination angle in derivation of cutter/rock interface *** extends the proposed kinematic and geometry based model to take into account the variable depth of cut in estimating the forces associated with cutting in one actuation *** were conducted using Wobble to test the predictions of the improved model at various operating *** model predictions are matched with the experimental results and effects of various factors are analysed.

关键词： Actuated disc cutting Undercutting Force model Wobble Hard rock cutting

Update on nutritional status,body composition and growth in paediatric inflammatory bowel disease

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World Journal of Gastroenterology 2014年第12期20卷 3191-3197页

作者： rebecca J hill Children’s Nutrition research Centre Queensland Children’s Medical Research Institute The University of QueenslandHerston School of Medicine The University of QueenslandHerston

Growth and nutritional status are important issues in paediatric inflammatory bowel disease(IBD).While linear growth is easy to assess,nutritional status is more complicated,with reports often compromised by the use of simple measures,such as weight and the body mass index,to assess nutritional status rather than more appropriate and sophisticated techniques to measure body *** review is an update on what is currently known about nutritional status as determined by body composition in paediatric ***,this review will focus on the impact of biologics on growth in paediatric *** lean mass deficits have been reported in children with IBD compared with controls,and there is evidence these deficits persist over ***,data imply that gender differences exist in body composition,both at diagnosis and in response to *** respect to growth improvements following treatment with biologics,there are conflicting *** some studies report enhancement of growth,others do *** relationship between disease severity,impaired growth and the requirement for biologics needs to be considered when interpreting these ***,key features associated with improvements in growth appear to be successful clinical response to treatment,patients in early stages of puberty,and the presence of growth failure at the onset of treatment.

关键词： Crohn’ s disease, Ulcerative colitis, Lean mass, Pubertal status, Infliximab, Inflammatory bowel disease

Prolog to the Section on radar System Engineering

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Journal of Systems Engineering and Electronics 1995年第1期6卷 46-47页

作者： hill, r. T. radar consultant, USA November, 1994, Beijing radar consultant USA November 1994 Beijing

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关键词： Prolog to the Section on radar System Engineering

Phage-mediated horizontal gene transfer and its implications for the human gut microbiome

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Gastroenterology report 2022年第1期10卷 78-89页

作者： Tatiana Borodovich Andrey N.Shkoporov r.Paul ross Colin hill APC Microbiome Ireland University College CorkCorkIreland School of Microbiology University College CorkCorkIreland

Horizontal gene transfer(HGT)in the microbiome has profound consequences for human health and *** spread of antibiotic resistance genes,virulence,and pathogenicity determinants predominantly occurs by way of *** exists of extensive horizontal transfer in the human gut *** transduction is a type of HGT event in which a bacteriophage transfers non-viral DNA from one bacterial host cell to *** abundance of tailed bacteriophages in the human gut suggests that transduction could act as a significant mode of HGT in the gut *** we review in detail the known mechanisms of phage-mediated HGT,namely specialized and generalized transduction,lateral transduction,gene-transfer agents,and molecular piracy,as well as methods used to detect phage-mediated HGT,and discuss its potential implications for the human gut microbiome.

关键词： gut phageome horizontal gene transfer gene transduction phage-mediated gene transfer

Supporting farmer-managed irrigation systems in the Shigar valley, Karakorum： role of the government and Aga Khan rural Support Programme

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Journal of Mountain Science 2017年第10期14卷 2064-2081页

作者： Joseph K.W.hill Department of rural Management Xavier Institute of Social Sciences (XISS) Dr Gamil Bulcke Path Post Box 7 Ranchi- 834001 India

Farmer-managed irrigation systems(FMIS) in the high altitude valleys of the Karakorum,Pakistan, continue to be managed effectively despite increased pressure on the social arrangements that sustain them. Colonial era records shows that over a century ago government agencies undertook irrigation support projects. In the past three decades,government agencies and the non-government agency Aga Khan rural Support Programme(AKrSP), which channels foreign funds into the region, have actively engaged in the provision of irrigation support. This article seeks to explore whether such projects support or undermine farmer-managed irrigation systems and the complex institutional arrangements that underpin them. Field research using ethnographic and participatory methods was conducted in spring 2013 in the upper Shigar valley, Skardu district, GilgitBaltistan. The findings show that irrigation development is a political activity that involves village-based actors, religious leaders, local politicians,and government and non-government *** agencies operate in a largely top-down,engineering mode, their larger projects limited to villages suffering water scarcity. The local government provides small funds for renovation work of FMIS,though allocation of funds is highly politicized. Nongovernment agencies, for a variety of reasons including donor-funding cycles, apply a one-size-fitsall ‘participatory' model in an attempt to socially engineer rules and institutions. In communities divided by factionalism the use of such external models that stress formation of committees are unlikely to yield positive results, and could instead contribute to undermining the very systems they seek to support. This research argues that irrigation interventions should take care to build upon the rich and complex social arrangements that have sustained FMIS through the centuries.

关键词： Farmer-managed irrigation systems Institutional arrangements Government Aga Khan rural Support Programme Shigar valley Karakorum

Emergence of the Wallerian degeneration pathway as a mechanism of secondary brain injury

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Neural regeneration research 2021年第5期16卷 980-981页

作者： Ciaran Scott hill Andrea Loreto National Hospital for Neurology and Neurosurgery University College London HospitalsUCL Cancer InstituteUniversity College LondonLondonUK Jon Van Geest Centre for Brain repair University of CambridgeCambridgeUK

Augustus Volney Wal ler was a renowned British neurophysiologist who birthed the axon degeneration field in 1850 by describing curdling and fragmentation of the glossopharyngeal and hypoglossal cranial nerves of a frog following a transection *** degeneration of axons after a transection injury is now known as Wallerian degeneration(WD).Waller’s work was expanded by Santiago ramón y Cajal who described in detail the morphological stages of WD from monitory fragmentation of the axon and the granular disintegration of the neurofibrils to the final resorption of the axon.

关键词： degeneration nerves Wallerian