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Occupational Eye Lens Radiation Dose While Performing Interventional Procedures over 18 Months Using a Face-Shield Equipped Suspended Radiation Protection System

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Open j.urnal of Radiology 2020年第2期10卷 101-114页

作者： thomas j. kwarcinski Andrew Lichliter j.seph Oros Niraj.KC Bryan Yoder Chet R. Rees Department of Radiology Baylor University Medical Center Dallas TX USA

Background: Numerous studies have demonstrated increasing evidence for cataractogenesis at lower levels of ionizing radiation than previously believed, with some suggesting possible absence of a threshold. Genetic differences between individuals also result in increased susceptibility in some operators, who might not be aware. European occupational exposure limits have been reduced and operators are seeking protective measures. Obj.ctive: To evaluate the protective effect of a face-shield equipped suspended protection system (Zero-Gravity®, TIDI Products, Neenah, WI) along with adherence to safety practices against radiation dose to the eye lens for an interventional radiologist performing a wide variety of procedures. Materials and Methods: In this institutional review board-approved single-institution study, one interventional radiologist wore a highly sensitive personnel monitoring dosimeter badge on the cap near the left eye while performing 299 procedures (3690 fluoroscopy minutes) over 18 consecutive months while utilizing the suspended protection system along with adherence to other generally recommended safety practices and movement away from the field during angiographic power inj.ctions. Dosimetry reports and procedural information were retrospectively reviewed. Results: Total lens dose equivalent to the left eye over 18 months was 0.11 mSv (annualized dose = 0.073 mSv, or 7.3 mRem). The patient-dose-area product standardized dose of 0.00576 μSv/Gy⋅cm2 is well below reports of conventional lead aprons, shields, and protective eyewear. Conclusion: Eye exposur

关键词： Lens Dose Reduction Radiation Safety Radiation-Induced Cataractogenesis Suspended Protection System

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Sleep as a window to understand and regulate Alzheimer's disease:emerging roles of thalamic reticular nucleus

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Neural Regeneration Research 2025年第6期20卷 1711-1712页

作者： Haoqi Sun Shiqian Shen Robert j.thomas M.Brandon Westover Can Zhang Department of Neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Center for Translational Pain Research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA Division of Pulmonary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging Research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

Introduction:Alzheimer 's disease(AD) is a common neurodegenerative disorder and the primary cause of dementia. Considerable evidence supports the “amyloid hypothesis,” stating that the pathogenesis of AD is primarily caused by the deposition of amyloid-β(Aβ), which drives tau phosphorylation, neuroinflammation, and neurodegeneration in the brain. The amyloid hypothesis is strengthened by the significant and moderate benefit of lecanemab, a humanized antibody through an anti-amyloid mechanism,showing slowed clinical decline(van Dyck et al.,2023). The recent positive results of anti-amyloid trials have brought back focus on the amyloid hypothesis through biochemical, genetic, and pharmacological approaches(Zhang, 2023).

关键词： Alzheimer inflammation hypothesis

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Laser cut hole matrices in novel armour plate steel for appliqué battlefield vehicle protection

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Defence Technology（防务技术） 2016年第5期12卷 351-359页

作者： Daniel j. thomas Engineering Manufacturing Centre College of Engineering Swansea University Swansea UK

During this research, experimental rolled homogeneous armour steel was cast, annealed and laser cut to form an appliqué plate. This Martensitic–Bainitic microstructure steel grade was used to test a novel means of engineering lightweight armour. It was determined that a laser cutting speed of 1200 mm/min produced optimum hole formations with limited distortion. The array of holes acts as a double-edged solution, in that they provide weight saving of 45%, providing a protective advantage and increasing the surface area. Data collected were used to generate laser cut-edge hole proj.ctions in order to identify the optimum cutting speed, edge condition, cost and deformation performance. These parameters resulted in the generation of a surface, with less stress raising features. This can result in a distribution of stress across the wider surface. Provided that appropriate process parameters are used to generate laser cut edges, then the hardness properties of the surface can be controlled. This is due to compressive residual stresses produced in the near edge region as a result of metallurgical transformations. This way the traverse cutting speed parameter can be adj.sted to alter critical surface characteristics and microstructural properties in close proximity to the cut-edge. A relationship was identified between the width of the laser HAZ and the hardness of the cut edge. It is the thickness of the HAZ that is affected by the laser process parameters which can be manipulated with adj.sting the traverse cutting speed.

关键词： Armour steels Defence systems Steel processing Armour engineering

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Expanding the phenotypic plasticity paradigm to broader views of trait space and ecological function

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Current Zoology 2016年第5期62卷 463-473页

作者： thomas j. DEWITT Department of Wildlife & Fisheries Sciences Texas A&M University College Station TX 77843-2258 USA

Foundational concepts of trait spaces, including phenotypic plasticity and function of traits, should be expanded and better integrated with ecological theory. This article addresses two areas where plasticity theory can become further integrated with ecological, evolutionary, and developmental thinking. First is the idea that not only trait means within environments and plasticity of trait means across environments is optimized by selection, but that the entire shape of phenotype distributions such as variance or skew should be optimized within and across environments. In order for trait distribution shape to evolve into adaptations, there must be a genetic basis for and selection upon variation in distribution shapes and their plasticities. I present published and new data demonstrating genetic control and selection for higher moments of phenotype distributions; though, plasticity in these values has not yet been tested. Genetic control of phenotype distribution moments is shown for Neurospora crassa ascospore size and shape. Selection on trait distribution moments is shown for Eurosta solidaginis gall size. Second, there is a tradition in modeling plasti- city as an adaptive strategy that pits it as an alternative to ecological specialization or generaliza- tion. However, these strategies need not be considered alternatives. Rather, with environmental fluctuation within generations plasticity may produce additive or non-additive intermediate （gener- alist） phenotypes, or something new altogether. I present published and new data on the snail Physa virgata and fish Gambusia affinis that show plasticity produces partly intermediate （general- ist） and partly unique phenotypic elements in mixed and fluctuating environments. Plasticity can thus be viewed in the context of a broader trait space and as having broader ecological roles than currently is conceived.

关键词： genetics of trait distributions multi-moment reaction norms non-additive plasticity off-plane phenotypes probabilisticoptimization selection on trait distributions specialists and generalists.

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The impact of macroalgae on mean and turbulent flow fields

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j.urnal of Hydrodynamics 2015年第3期27卷 427-435页

作者： thomas Robert E. MCLELLAND Stuart j. Department of Geography Environment and Earth Sciences University of Hull

In this paper, we attempt to quantify the mean and turbulent flow fields around live macroalgae within a tidal inlet in Norway. Two Laminaria digitata specimens - 0.50 m apart were selected for detailed study and a profiling ADV was used to collect 45 velocity profiles, each composed of up to seven 0.035 m-high profiles collected for 240 s at 100 Hz, at a streamwise spacing of 0.25 m and cross-stream spacing of 0.20 m. To quantify the impact of the macroalgae, measurements were repeated over a sparser grid after the region had been completely cleared of algae and maj.r roughness elements.

关键词： dealiasing laminaria digitata turbulence vectrino profiler velocity profile

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Can inhibition of telomerase increase pancreatic cancer cell's susceptibility to chemotherapeutic reagents?

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Hepatobiliary & Pancreatic Diseases International 2002年第1期1卷 155-160页

作者： thomas j.Ⅲ Fahey Department of Surgery Cornell University Medical College New York NY USA

Obj.ctives: To clarify the inhibition of pancreatic can-cer cells by interference with the hTR component of thetelomerase reverse transcriptase enzymatic complexand evaluate susceptibility of antisense hTR pancreaticcancer cells to chemotherapeutic ***: A 593 bp of full length hTR cDNA was sub-cloned into a mammalian expression vector pcDNA3.1(-) in antisense orientation to construct an antisensehTR expression plasmid. The plasmids were introducedinto Pancl cells, a human pancreatic carcinoma cellline, by lipofectin, and G418-resistant stable trans-formants were expanded. Resulting stable clones werescreened for the presence of hTR insert by PCR withT7 and BGH reverse primers located on the flanks ofthe multiclonal site of pcDNA3.1 vector. Cell growth rate,hTR expression, telomerase activity, and anchorage-in-dependent growth property were analyzed. Finally, sus-ceptibility of antisense hTR cells to chemotherapeuticreagents was ***: Significant downregulation of endogenous hTRwas evident in the antisense-hTR transformed cells,and telomerase activity was markedly decreased com-pared to control cells in standard TRAP assays. Fur-thermore, the proliferation and the anchorage-inde-pendent growth ability in antisense-hTR expressingcells were significantly decreased compared with thecontrol parental cells. However, no crisis or senescencephenomena was observed. Antisense hTR appears toincrease Pancl cell's susceptibility to chemotherapeuticreagent cDDP, but not to differentiation reagent DM-SO, COX2 inhibitor sulinbac, NS-398, curcumin, andchemotherapeutic reagent adriamycin(ADM).Conclusions: These data indicate that hTR is probablya critical component of human telomerase activity andthat downregulation of the RNA component of humantelomerase is an effective target for anticancer strategyand antisense hTR can increase Pancl cell's susceptibilityto cDDP.

关键词： Telomerase hTR Antisense Pancreatic carcinoma cellline chemotherapeutic reagents

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Particle flow simulations with homogenised lattice Boltzmann methods

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Particuology 2017年第5期15卷 1-13页

作者： Mathias j. Krause Fabian Klemens thomas Henn Robin Trunk Hermann Nirschl Institute for Applied and Numerical Mathematics Karlsruhe Institute of Technology 76021 Karlsruhe Germany Institute for Mechanical Process Engineering and Mechanics Karlsruhe Institute of Technology 76021 Karlsruhe Germany

An alternative approach to simulating arbitrarily shaped particles submersed in viscous fluid in two dimensions is proposed, obtained by adapting the velocity parameter of the equilibrium distribution function of a standard lattice Boltzmann method （LBM）. Comparisons of exemplifying simulations to results in the literature validate the approach as well as the convergence analysis. Pressure fluctuations occurring in Ladd＇s approach are greatly reduced. In comparison with the immersed boundary method, this approach does not require cost intensive interpolations. The parallel efficiency of LBM is retained. An intrinsic momentum transfer is observed during particle-particle collisions. To demonstrate the capa- bilities of the approach, sedimentation of particles of several shapes is simulated despite omitting an explicit particle collision model.

关键词： Particulate flow simulationsArbitrarily shaped particlesLattice Boltzmann methodsValidationSedimentation processes

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Regional climate model downscaling may improve the prediction of alien plant species distributions

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Frontiers of Earth Science 2014年第4期8卷 457-471页

作者： Shuyan LIU Xin-Zhong LIANG Wei GAO thomas j. STOHLGREN Earth System Science Interdisciplinary Center University of Maryland College Park MD 20740 USA Department of Atmospheric and Oceanic Sciences University of Maryland College Park MD 20740 USA Department of Ecosystem Science and Sustainability Colorado State University Fort Collins CO 80523 USA Fort Collins Science Center U.S. Geological Survey Fort Collins CO 80526 USA

Distributions of invasive species are commonly predicted with species distribution models that build upon the statistical relationships between observed species presence data and climate data. We used field observations, climate station data, and Maximum Entropy species distribution models for 13 invasive plant species in the United States, and then compared the models with inputs from a General Circulation Model （hereafter GCM-based models） and a downscaled Regional Climate Model （hereafter, RCM-based models）. We also compared species distributions based on either GCM-based or RCM-based models for the present （1990-1999） to the future （2046- 2055）. RCM-based species distribution models replicated observed distributions remarkably better than GCM- based models for all invasive species under the current climate. This was shown for the presence locations of the species, and by using four common statistical metrics to compare modeled distributions. For two widespread invasive taxa （Bromus tectorum or cheatgrass, and Tamarix spp. or tamarisk）, GCM-based models failed miserably to reproduce observed species distributions. In contrast, RCM-based species distribution models closely matched observations. Future species distributions may be significantly affected by using GCM-based inputs. Because invasive plants species often show high resilience and low rates of local extinction, RCM-based species distribution models may perform better than GCM-based species distribution models for planning containment programs for invasive species.

关键词： climate change species distribution model,Maxent downscaling

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Felsenstein＇s ＂one-allele model＂ of speciation： The role of philopatry in the initial stages of host plant mediated reproductive isolation in Enchenopa binotata

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Current Zoology 2013年第5期59卷 658-666页

作者： Frank W. STEARNS Kelley j. TILMON thomas K. WOOD Department of Biology Biology-Psychology Building University of Maryland College Park MD 20742 USA Department of Plant Science Plant Science Building South Dakota State University Brookings SD 57007 USA Department of Entomology and Applied Ecology 250 Townsend Hall University of Delaware Newark DE 19716 USA

The study of speciation genetics is primarily concerned with identifying the genetic traits that allow divergent selec- tion to overcome the homogenizing effects of gene flow. Felsenstein reviewed this race between gene flow and selection, con- cluding that speciation with gene flow was unlikely under a ＂two-allele model＂（where two traits were necessary for reproductive isolation） but that divergence could occur quite easily under a ＂one-allele model.＂ Despite this finding, much of the sympatric speciation research involving phytophagous insects has relied on a two-trait model, where insects evolve both preferences for and increased performance on novel host plants. Philopatry （a tendency to remain where one was born） is known to occur in phyto- phagous insects and is a single trait isolation mechanism. However, it is traditionally invoked as simply augmenting reproductive isolation. Species in the Enchenopa binotata complex are believed to have speciated in sympatry. They exhibit host plant prefe- rences, host specific performance advantages and strong philopatry. We experimentally shifted E. binotata to evolutionarily novel host plants. Previous research has demonstrated that the experimental population of insects possesses genetic variation in prefe- rence and performance to the novel host. The degree of philopatry at mating and egg-laying was assayed for the first four years under full choice conditions. Host plant preference and performance was assayed after eight years. Philopatry was an immediate and strong isolating mechanism, while preference for and performance on the novel host lagged. We therefore suggest that philo- patry may be a more important mechanism in the early stages of a host shift than previously believed [Current Zoology 59 （5）： 658-666, 2013].

关键词： Philopatry Enchenopa Ecological Speciation Sympatric Speciation

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Determination of quantitative structure-property and structure-process relationships for graphene production in water

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Nano Research 2015年第6期8卷 1865-1881页

作者： thomas j. Nacken Cornelia Damm Haichen Xing Andreas ROger Wolfgang Peukert Institute of Particle Technology (LFG) Friedrich-Alexander University Erlangen-NOrnberg (FAU) Cauerstrasse 4 91058 Erlangen Germany

A scalable method for graphene and few-layer graphene （FLG） production by graphite delamination in aqueous solutions of the nonionic surfactant TWEEN 80 （TW80） using stirred-media mills is presented. Delaminated product analysis using statistical Raman spectroscopy yielded extensive processing-structure-property relationships that revealed how stress intensity and specific energy input, i.e., the process parameters, govern the yield of graphene production and defect formation. The dispersed carbon concentration increased but the content and the quality of the FLG product decreased sharply with higher specific energy input. The FLG content of the product was up to 90%, especially for low specific energy input. Moreover, Raman analyses revealed that stress intensities greater than about I nj.were related to significant defect formation in the product particles. Another key parameter for graphene production is solvent viscosity. The FLG concentration in the product increased by a factor of 10 when the solvent＇s viscosity was increased from 1 to 6 mPa-s because shear- and friction-induced delamination was enhanced and in-plane fracture was reduced due to dampening of bead motion. Based on the processing-structure-property relationships found, we propose that the delamination process can be designed in such way that the product consists, almost totally, of FLG and that single-layer graphene is produced. The scalability of graphene production by stirred-media delamination was demonstrated when an increase in the batch size from 0.2 to 2 L had no significant effect on product quality.

关键词： graphite delamination few-layer graphene graphene stirred-media millprocess parameters statistical Ramanspectroscopy

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