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991.
Hagerman RJ Miller LJ McGrath-Clarke J Riley K Goldson E Harris SW Simon J Church K Bonnell J Ognibene TC McIntosh DN 《Microscopy research and technique》2002,57(3):168-173
Attention Deficit Hyperactivity Disorder (ADHD) is seen in the majority of children with Fragile X Syndrome (FraX). Previous work has documented an enhanced sweat response to stimuli in children with FraX compared to controls utilizing electrodermal response (EDR) measures. The present study assesses the EDRs both on and off stimulants in 19 children with ADHD and FraX compared to 17 age- and IQ-matched control patients with ADHD and developmental delays. Although the baseline EDRs were comparable between FraX patients and controls, the patients with FraX had a significant decrease in EDR amplitude and number of peaks when treated with stimulants compared to controls. This suggests that patients with FraX are more responsive to the enhancement of inhibitory systems that occur with stimulant use for ADHD. The use of a quantifiable measure, such as EDR, is recommended in future studies of treatment efficacy. 相似文献
992.
Boosting the Efficiency of Perovskite Solar Cells with CsBr‐Modified Mesoporous TiO2 Beads as Electron‐Selective Contact 下载免费PDF全文
Ji‐Youn Seo Ryusuke Uchida Hui‐Seon Kim Yasemin Saygili Jingshan Luo Chris Moore Julie Kerrod Anthony Wagstaff Mike Eklund Robert McIntyre Norman Pellet Shaik M. Zakeeruddin Anders Hagfeldt Michael Grätzel 《Advanced functional materials》2018,28(15)
Rapid extraction of photogenerated charge carriers is essential to achieve high efficiencies with perovskite solar cells (PSCs). Here, a new mesoscopic architecture as electron‐selective contact for PSCs featuring 40 nm sized TiO2 beads endowed with mesopores of a few nanometer diameters is introduced. The bimodal pore distribution inherent to these films produces a very large contact area of 200 m2 g?1 whose access by the perovskite light absorber is facilitated by the interstitial voids between the particles. Modification of the TiO2 surface by CsBr further strengthens its interaction with the perovskite. As a result, photogenerated electrons are extracted rapidly producing a very high fill factor of close to 80% a VOC of 1.14 V and a PCE up to 21% with negligible hysteresis. 相似文献
993.
Algorithms are described which allow a significant reduction of the effects of multiple pulses, which originate from pulse reflections within terahertz (THz) emitters. The algorithms are based on models for the pulse propagation inside the emitter. Model parameters can be estimated from a calibration experiment using a reference signal in the absence of a sample. The parameters once estimated for a particular emitter device, can then be used to suppress the effects of multiple pulses in all measurements performed with the same emitter. The application of this method is demonstrated in the investigation of a disc sample and in the investigation of a paint layer. 相似文献
994.
Raphael Schmager Julie Roger Jonas A. Schwenzer Fabian Schackmar Tobias Abzieher Mahdi Malekshahi Byranvand Bahram Abdollahi Nejand Matthias Worgull Bryce S. Richards Ulrich W. Paetzold 《Advanced functional materials》2020,30(9)
High‐efficiency perovskite‐based solar cells can be fabricated via either solution‐processing or vacuum‐based thin‐film deposition. However, both approaches limit the choice of materials and the accessible device architectures, due to solvent incompatibilities or possible layer damage by vacuum techniques. To overcome these limitations, the lamination of two independently processed half‐stacks of the perovskite solar cell is presented in this work. By laminating the two half‐stacks at an elevated temperature (≈90 °C) and pressure (≈50 MPa), the polycrystalline perovskite thin‐film recrystallizes and the perovskite/charge transport layer (CTL) interface forms an intimate electrical contact. The laminated perovskite solar cells with tin oxide and nickel oxide as CTLs exhibit power conversion efficiencies of up to 14.6%. Moreover, they demonstrate long‐term and high‐temperature stability at temperatures of up to 80 °C. This freedom of design is expected to access both novel device architectures and pairs of CTLs that remain usually inaccessible. 相似文献
995.
Mike Powers Jianbiao Pan Julie Silk Patrick Hyland 《Journal of Electronic Materials》2012,41(2):224-231
Au over Ni on Cu is a widely used printed circuit board (PCB) surface finish, under bump metallization (UBM), and component
lead metallization. It is generally accepted that less than 3 wt.% Au in Sn-Pb solder joints inhibits formation of detrimental
intermetallic compounds (IMC). However, the critical limit for Au content in Pb-free solder joints is not well established.
Three surface-mount package platforms, one with a matte Sn surface finish and the others with Ni/Au finish, were soldered
to Ni/Au-finished PCB using Sn-3.0Ag-0.5Cu (SAC305) solder, in a realistic manufacturing setting. The assembled boards were
divided into three groups: one without any thermal treatment, one subjected to isothermal aging at 125°C for 30 days, and
the third group aged at 125°C for 56 days. Representative solder joints were cross-sectioned and analyzed using scanning electron
microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDX) to investigate the evolution of the solder joint morphology
as a function of Au content and isothermal aging. It was found that, if Cu is available to dissolve in the solder joint, the
migration of AuSn4 from the bulk to the interface as a result of thermal aging is mitigated. 相似文献
996.
Xin Chen Santosh Pandit Lei Shi Vaishnavi Ravikumar Julie Bonne Køhler Ema Svetlicic Zhejian Cao Abhroop Garg Dina Petranovic Ivan Mijakovic 《Advanced functional materials》2023,33(45):2304053
Alzheimer's disease (AD) is the most prevalent neurodegenerative disease, with the aggregation of misfolded amyloid-β (Aβ) peptides in the brain being one of its histopathological hallmarks. Recently, graphene oxide (GO) nanoflakes have attracted significant attention in biomedical areas due to their capacity of suppressing Aβ aggregation in vitro. The mechanism of this beneficial effect has not been fully understood in vivo. Herein, the impact of GO on intracellular Aβ42 aggregates and cytotoxicity is investigated using yeast Saccharomyces cerevisiae as the model organism. This study finds that GO nanoflakes can effectively penetrate yeast cells and reduce Aβ42 toxicity. Combination of proteomics data and follow-up experiments show that GO treatment alters cellular metabolism to increases cellular resistance to misfolded protein stress and oxidative stress, and reduces amounts of intracellular Aβ42 oligomers. Additionally, GO treatment also reduces HTT103QP toxicity in the Huntington's disease (HD) yeast model. The findings offer insights for rationally designing GO nanoflakes-based therapies for attenuating cytotoxicity of Aβ42, and potentially of other misfolded proteins involved in neurodegenerative pathology. 相似文献
997.
运营商一直在提高网络带宽和可靠性,以提供更多的增值业务,而家庭联网技术方案将帮助运营商把这些应用延伸到家庭,从而充分挖掘这些增值业务的潜力。 相似文献
998.
Hybrid halide perovskite has established its credibility as high performance thin film photovoltaic technology. Perovskite based on formamidinium cation is at the core composition to top performances and stability. Herein, a depth study based on temperature-controlled in situ X-ray diffraction focusing on the photo-active formamidinium lead iodide (α-FAPbI3) is reported. In particular, the thermal stability of the latter and the degradation pathways under different experimental conditions are clarified. Based on this in situ technique, the lattice thermal expansion coefficient is reported that provides relevant information on possible mechanical stress created upon temperature cycling or damp heat test. The results support that α-FAPbI3 degradation is substantially accelerated when temperature is combined to illumination and when it is interfaced with the extraction layers. In addition, by contrast to in darkness for which α-FAPbI3 degrades directly into PbI2, the existence of a temperature gap under illumination involving an intermediate step with a non-crystalline phase resulting from the perovskite degradation and contributing to the formation of PbI2 by-product is revealed. 相似文献
999.
High Performance Organic Transistors Using Small Molecule Semiconductors and High Permittivity Semiconducting Polymers 下载免费PDF全文
Keri L. McCall Simon R. Rutter Elizabeth L. Bone Neil D. Forrest James S. Bissett Julie D. E. Jones Michael J. Simms Aaron J. Page Raymond Fisher Beverley A. Brown Simon D. Ogier 《Advanced functional materials》2014,24(20):3067-3074
High mobility organic semiconductor formulations with excellent uniformity across large area substrates are prepared via the use of formulations containing small molecule and high permittivity semiconducting oligomers. The use of these high‐k (k > 3.3) oligomers allows control of the wetting via the manipulation of the surface energy of the substrate being coated. Organic thin film transistors results with mobilities of up to 5 cm2 V‐1 s‐1, standard deviation <10 %, on/off ratios of 109 are presented. 相似文献
1000.
AL Edinger JL Mankowski BJ Doranz BJ Margulies B Lee J Rucker M Sharron TL Hoffman JF Berson MC Zink VM Hirsch JE Clements RW Doms 《Canadian Metallurgical Quarterly》1997,94(26):14742-14747
Brain capillary endothelial cells (BCECs) are targets of CD4-independent infection by HIV-1 and simian immunodeficiency virus (SIV) strains in vitro and in vivo. Infection of BCECs may provide a portal of entry for the virus into the central nervous system and could disrupt blood-brain barrier function, contributing to the development of AIDS dementia. We found that rhesus macaque BCECs express chemokine receptors involved in HIV and SIV entry including CCR5, CCR3, CXCR4, and STRL33, but not CCR2b, GPR1, or GPR15. Infection of BCECs by the neurovirulent strain SIV/17E-Fr was completely inhibited by aminooxypentane regulation upon activation, normal T cell expression and secretion in the presence or absence of ligands, but not by eotaxin or antibodies to CD4. We found that the envelope (env) proteins from SIV/17E-Fr and several additional SIV strains mediated cell-cell fusion and virus infection with CD4-negative, CCR5-positive cells. In contrast, fusion with cells expressing the coreceptors STRL33, GPR1, and GPR15 was CD4-dependent. These results show that CCR5 can serve as a primary receptor for SIV in BCECs and suggest a possible CD4-independent mechanism for blood-brain barrier disruption and viral entry into the central nervous system. 相似文献