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Cellular and molecular mechanisms implicated in pathogenesis of selective neurodegeneration in Huntington＇s disease

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Frontiers of physics 2012年第5期7卷 459-476页

作者： jeffrey r CANTLE Center for Neurobehavioral Genetics Semel Institute for Neuroscience & Human Behavior David Geffen School of Medicine at UCLA_ University of California Los Angeles CA 90095 USA DepartmentofPsychiatry & Biobehavioral Sciences David Geffen School of Medicine at UCLA University of California Los Angeles CA 90095 USA Brain research Institute. David Geffen School of Medicine at UCLA University of California Los Angeles CA 90095 USA Interdepartmental Program for Neuroscience David Geffen School of Medicine at UCLA University of CaliJbrnia Los Angeles CA 90095 USA

Huntington＇s disease （HD） is one of the most common dominantly-inherited neurodegenerative disorders and is caused by a CAG repeat expansion in the huntingtin gene. HD is characterized by selective degeneration of subpopulations of neurons in the brain, however the precise underlying mechanisms how a ubiquitously expressed disease protein could target specific types of neurons for degeneration remains a critical, yet unanswered question for HD and other major neurodegenerative disorders. In this review, we describe the expanding view of selective neuronal vulnerability in HD, based on recent neuropathological and neuroimaging studies. We will also summarize the systematic effort to define the cell types in which mutant Huntingtin expression is critical for pathogenesis of vulnerable neurons in the striatum and cortex. Finally, we will describe selected, emerging molecular mechanisms that are implicated in selective disease processes in HD. Together, the field has begun to appreciate the distinct molecular pathogenic roles of mutant huntingtin in different cell types that may contribute to the selective neuronal vulnerability, with dissection of such mechanisms likely to yield novel molecular targets for HD therapy.

关键词： Huntington's disease neurodegeneration selective neuronal vulnerability cortex striatum conditional mouse model cell-autonomous toxicity pathological cell-cell interaction pathogenesis therapeutic targets

Amplitude-mode spectroscopy of chemically injected and photogenerated charge carriers in semiconducting single-walled carbon nanotubes

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Nano research 2023年第4期16卷 5619-5625页

作者： Shai r。Vardeny Alan Phillips Kira A。Thurman ZValy Vardeny jeffrey L.Blackburn Division of Electrical Electronicand Infocommunications EngineeringOsaka University2-1 Yamada-okaSuitaOsaka 565-0871Japan Materials Chemistryand Computation Science DirectorateNational Renewable Energy LaboratoryGoldenCO 80401USA Department of Physics Colorado School of MinesGoldenCO 80401USA Department of Physics&Astronomy University of UtahSalt Lake CityUT 84112USA

In one-dimensional semiconductors such as conjugated polymers and semiconducting single-walled carbon nanotubes(s-SWCNTs),injected charge carriers(electrons or holes)can have profound impacts on both electronic conductivity and optical spectra,even at low carrier *** charge-related spectral features is a key fundamental challenge with important technological ***,we employ a systematic suite of experimental and theoretical tools to understand the mid-infrared charge signatures of heavily p-type doped polymer-wrapped *** a broad range of nanotube diameters,we find that hole charge carriers induce strong Fano anti-resonances in mid-infrared transmission spectra that correspond to defect-related(D-band)and in-plane tangential(G-band)raman-active vibrational modes,along with antiresonances arising from infrared(Ir)-active polymer and SWCNT *** employ^(13)C isotope-labeled s-SWCNTs and a removable wrapping polymer to clarify the relative intensities,energies,and sources of all observed *** performed with the“amplitude mode model”are used to quantitatively reproduce raman spectra and also help to explain the outsized intensity of the D-band anti-resonance,relative to the G-band,observed for both moderately and degenerately doped *** results provide a framework for future studies of ground-and excited-state charge carriers in s-SWCNTs and a variety of low-dimensional materials.

关键词： carbon nanotubes doping charge carriers phonons electron-phonon coupling

Chemically activated carbon nanofibers for adsorptive removal of bisphenol-A:Batch adsorption and breakthrough curve study

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Chinese Journal of Chemical Engineering 2023年第9期61卷 248-259页

作者： Wenming Hao Basma I.Waisi Timothy M.Vadas jeffrey r.McCutcheon College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China Department of Chemical&Biomolecular Engineering University of ConnecticutStorrsCT 06269United States Department of Chemical Engineering University of BaghdadBaghdad 10071Iraq Department of Civil and Environmental Engineering University of ConnecticutStorrsCT 06269United States

Activated carbon nanofibers(ACNFs)with small diameter can significantly increase the accessibility of intra pores and accelerate adsorption of molecules from *** this study,ACNFs were made by blending K_(2)CO_(3)or ZnCl_(2)as the activating agent into the polyacrylonitrile(PAN)in dimethylformamide solution for electrospinning prior to ***-A(BPA),an endocrine disruption pollutant,is widely applied in the production of polycarbonate plastics and epoxy ***,BPA is often used as a model contaminant commonly removed via *** adsorption studies were used to evaluate the kinetics and adsorption capacity of the ***-Peterson(r-P)and Langmuir models were found to fit the isotherm of BPA adsorption better than Freundlich model,showing the homogeneous nature of the PAN originated *** adsorption kinetics was better described by the pseudo second-order model than that by the pseudo first-order *** fitting by intraparticle diffusion model indicates the adsorption of BPA onto ACNFs is mainly controlled by pore *** pH value and ionic strength reduced BPA adsorption from aqueous *** breakthrough curves studied in two different fixed bed systems(cross flow bed system and packed flow bed system)confirmed the scalability of BPA removal by ACNFs in dynamic adsorption *** modified dose-response model predicted well the fixed-bed outlet concentration profiles.

关键词： Activated carbon nanofibers(ACNFs) Chemical activation Bisphenol-A(BPA) Fixed bed Adsorption

A database of modeled gridded dry deposition velocities for 45 gaseous species and three particle size ranges across North America

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Journal of Environmental Sciences 2023年第5期127卷 264-272页

作者： Leiming Zhang Zhuanshi He Zhiyong Wu Anne Marie Macdonald jeffrey r.Brook Shailesh Kharol Air Quality research Division Science and Technology BranchEnvironment and Climate Change CanadaTorontoON M3H 5T4Canada Department of Chemical Engineering and Applied Chemistry University of TorontoTorontoON M5S 2E4Canada

The dry deposition process refers to the flux loss of an atmospheric pollutant due to uptake of the pollutant by the earth’s *** deposition flux of a chemical species is typically calculated as the product of its surface-layer concentration and its dry deposition velocity(V_(d)).Field measurement based V_(d) data are very scarce or do not exist for many chemical species considered in chemistry transport *** the present study,gaseous and particulate dry deposition schemes were applied to generate a database of hourly V_(d) for 45 gaseous species and three particle size ranges for two years(2016–2017)at a 15 kmby 15 km horizontal resolution across North *** V_(d) of the 45 gaseous species ranged fromross the whole domain,with chemical species-dependentmedian(mean)values being in the range of 0.018–1.37 cm/sec(0.05–1.43 cm/sec).The spatial distributions of the two-year average V_(d) showed values higher than 1–3 cm/sec for those soluble and reactive species over certain land *** species have the highest V_(d) over water surfaces,while insoluble but reactive species have the highest V_(d) over *** V_(d) of PM_(2.5) across the whole domain ranged from 0.039 to 0.75 cm/sec with median(mean)value of 0.18(0.20)cm s^(−1),while the mean V_(d) for PM_(2.5)–10 is twice that of PM_(2.5).Uncertainties in the modeled V_(d) are typically on the order of a factor of 2.0 or larger,which needs to be considered when applying the dataset in other studies.

关键词： Air quality modeling Atmospheric pollutant Atmospheric deposition Dry deposition velocity Spatiotemporal distribution

Microenvironmental influences on T cell immunity in cancer and inflammation

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Cellular & Molecular Immunology 2022年第3期19卷 316-326页

作者： Darren r.Heintzman Emilie L.Fisher jeffrey C.rathmell Department of Pathology Microbiologyand ImmunologyVanderbilt University Medical CenterNashvilleTN37205USA Vanderbilt Center for Immunobiology Vanderbilt University Medical CenterNashvilleTN37205USA

T cell metabolism is dynamic and highly *** the intrinsic metabolic programs of T cell subsets are integral to their distinct differentiation and functional patterns,the ability of cells to acquire nutrients and cope with hostile microenvironments can limit these pathways.T cells must function in a wide variety of tissue settings,and how T cells interpret these signals to maintain an appropriate metabolic program for their demands or if metabolic mechanisms of immune suppression restrain immunity is an area of growing *** in inflamed and cancer tissues,a wide range of changes in physical conditions and nutrient availability are now acknowledged to shape *** include fever and increased temperatures,depletion of critical micro and macro-nutrients,and accumulation of inhibitory waste *** we review several of these factors and how the tissue microenvironment both shapes and constrains immunity.

关键词： immunometabolism T cell microenvironment cancer inflammation

A versatile acoustically active surface based on piezoelectric microstructures

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Microsystems & Nanoengineering 2022年第3期8卷 51-60页

作者： Jinchi Han Mayuran Saravanapavanantham Matthew r.Chua jeffrey H.Lang Vadimir Bulovic Department of Electrical Engineering and Computer Science Massachusetts Institute of TechnologyCambridgeMA 02139USA

We demonstrate a versatile acoustically active surface consisting of an ensemble of piezoelectric microstructures that are capable of radiating and sensing acoustic waves.A freestanding microstructure array embossed in a single step on a flexible piezoelectric sheet of polyvinylidene fluoride(PVDF)leads to high-quality acoustic performance,which can be tuned by the design of the embossed *** high sensitivity and large bandwidth for sound generation demonstrated by this acoustically active surface outperform previously reported thin-flm loudspeakers using PVDF,PVDF copolymers,or voided charged polymers without *** further explore the directivity of this device and its use on a curved *** addition,high-fidelity sound perception is demonstrated by the surface,enabling its microphonic application for voice recording and speaker *** versatility,high-quality acoustic performance,minimal form factor,and scalability of future production of this acoustically active surface can lead to broad industrial and commercial adoption for this technology.

关键词： surface. piezoelectric versatile

THE MErGING OF TWO UNEQUAL AXISYMMETrIC PArALLEL TUrBULENT JETS

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Journal of Hydrodynamics 2012年第2期24卷 257-262页

作者： BArATIAN-GHOrGHI Zahra KAYE Nigel B. KHAN Abdul A. SMITH jeffrey r. Glenn Department of Civil Engineering Clemson University

results of an experimental study of the merging of unequal parallel round turbulent jets are *** were conducted for a jet axial separation to nozzle diameter ratio of 3.0 and the reynolds numbers ranging from 8 000 to 15 *** distance to the point where the jets are merged was measured for a range of jet source momentum flux *** different merger criteria were used based on the mean velocity profile,mean passive tracer concentration profile,and reynolds stress *** results show that the concentration profile merges closest to the jet sources followed by the velocity profile with the reynolds stress profile merging furthest from the *** all three profiles the merge distance is relatively insensitive to the momentum flux ratio,consistent with previous findings for slot jets and buoyant round *** measured merge distances are consistent with previously published results for equal round jets,though the poor spatial resolution of data in the literature means that limited comparison is *** are no studies of unequal jet merger currently in the literature that could be used for comparison.

关键词： turbulent jet merging jets unequal jets experiment

Placental accommodations for transport and metabolism during intra-uterine crowding in pigs

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Journal of Animal Science and Biotechnology 2015年第2期6卷 163-176页

作者： jeffrey L Vallet Anthony K Mc Neel Jeremy r Miles Bradley A Freking U.S. Department of Agriculture Agricultural Research Service U.S. Meat Animal Research CenterState Spur 18D Clay Center NE 68933 USA

Litter size and birth weights are limited by uterine capacity, defined as the ability of the uterus to maintain the appropriate development of some number of conceptuses. Uterine capacity is the result of the combined effects of uterine, placental and embryo/fetal function. The number of living conceptuses that the uterus is capable of supporting is greater during early gestation compared to later gestation. Plots of log fetal weight versus log placental weight also indicate that fetal weights are less sensitive to reduced placental weight （and therefore reduced intrauterine space） in early gestation compared to late gestation. However, even in late gestation, mechanisms still exist that maintain fetal growth when the size of the placenta is reduced. One such mechanism is likely to be improved development of the folded placental-epithelial/maternal-epithelial bilayer. Fold depth, and therefore the maternal fetal interactive surface, increases as gestation advances and is greater in placenta from smal fetuses. On the fetal side of the placenta, the epithelial bilayer is embedded in stromal tissue. Glycosaminoglycans are major components of stroma, including hyaluronan and heparan sulfate. Hyaluronidases and heparanases are present within placental tissues, and likely play roles in modification of stromal components to facilitate fold development. Glycosaminoglycans are polymers of forms of glucose （glucosamine, glucuronic acid, iduronic acid） suggesting that glycosaminoglycan synthesis may compete with the glucose needs of the developing fetus. Pig conceptuses are fructogenic, such that a substantial portion of glucose transferred from mother to fetus is converted to fructose. Fructose is an intermediate product in the synthesis of glucosamine from glucose, and glucosamine is linked to regulation of trophoblast cell proliferation through regulation of mTOr. These findings suggest a link between glucose, fructose, glucosamine synthesis, GAG production, and placental m

关键词： Glycosaminoglycans Nutrient transport Placenta

Building momentum for sustainable behaviors in developing regions using Locally Managed Decentralized Circular Economy principles

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Chinese Journal of Chemical Engineering 2019年第7期27卷 1566-1571页

作者： Chandni Joshi jeffrey Seay Department of Chemical and Materials Engineering University of Kentucky

Despite the current threat from climate change,plastic collecting in the world's oceans,and the steady loss of biodiversity,the world continually fails to take action with regard to our rapidly changing ***,waiting on governments to act is no longer a viable *** change is needed and the pace of diplomacy is simply too *** governments are reactionary and taking action to solve future problems is not a priority,even as the threat of potential ecological catastrophe draws ever *** is in the hands of individuals,and it is our decisions and behaviors that will influence the future of our planet and our ability to inhabit ***,building momentum for sustainable behavior must begin with *** neoliberal approach to environmental protection posits that individuals are motivated by rational self-interest,and that economic incentives are necessary to achieve environmental ***,recent research suggests that monetary gain alone actually negatively impacts behavior,and often neglects the rural *** a result,models for projects designed to benefit the environment need more than just a monetary incentive,they must incorporate all three pillars of sustainability:environment,economy and *** approach for building momentum for sustainable behavior with regard to municipal solid waste management,particularly in the developing world,is by implementing Locally Managed Decentralized Circular Economy(LMDCE)*** contribution will describe the role behavioral economics plays in the choices made by producers and *** results of a case study on applying LMDCE principles in Uganda to manage waste plastic accumulation by conversion to fuel oil will be presented.

关键词： Pyrolysis Fuel Pollution Appropriate technology Behavioral economics Municipal solid waste