gebhart/patrepeval huggingface dataset:
FDTD Simulations of LEMP Propagation in the Earth-Ionosphere Waveguide Using Different Lightning Models (2021)

In this article, vertical electric fields (including skywaves) produced by lightning return strokes at distances ranging from 100 to 958 km have been computed using the finite-difference time-domain (FDTD) method in the 2-D spherical coordinate system. The return stroke is represented by the original transmission-line (TL) model (with no current decay with height and abrupt current termination at the channel top), the modified TL model with linear current decay with height (MTLL model), the modified TL model with exponential current decay with height (MTLE model), or the Hertzian dipole (HD) model. All the TL-type models include propagation delay, while in the HD model the current changes with time, but does so simultaneously in all channel sections; that is, without any propagation delay. The HD model predicts considerably higher fields than the TL-type models, if the same channel length is employed. The HD model with an unrealistically small channel length of 0.7 km yields electric field peaks similar to those produced by TL-type models with a 7-km channel. Ground waves and skywaves computed using the HD model have faster rise and decay times (shorter pulsewidths) than those computed using a TL-type model. Electric fields produced by a longer risetime current are less attenuated due to propagation over lossy ground when a TL-type model is used, while they are more attenuated if the HD model is employed. The opposite trends are related to the fact that the radiation field peak is proportional to the product of the current and propagation speed for a TL-type model, while for the HD model, it is proportional to the product of the time derivative of current and channel length. In the TL model, abrupt termination of significant current at the channel top results in the so-called mirror image (abrupt radiation field polarity change). This artifact does not occur in the framework of the MTLL model and is negligible in the MTLE model with λ = 2 km and H = 7 km.
Maskless selective growth of InGaAs/InP quantum wires on (100)GaAs (1997)

A new fabrication process to create InGaAs/InP quantum wires on (100) GaAs substrates is demonstrated. The process is based on the selectivity of the growth of InP on lines created by focused ion beam bombardment, together with the selectivity of the growth of InGaAs on the InP wires. Intense photoluminescene is observed from the wires and the emission shows clear polarization parallel and perpendicular to the wires. Cathodoluminescene images confirm that the luminescence originates from the wires.
Schwann cell heparan sulfate proteoglycans play a critical role in glial growth factor/neuregulin signaling (1996)

Glial growth factors are proteins encoded by the neuregulin gene and are thought to signal via receptor tyrosine kinases. Many neuregulin gene products bind heparin, and we hypothesize that affinity for heparin may implicate cell surface heparan sulfate proteoglycans (HeSPGs) as co-receptors for the soluble neuregulin gene product, recombinant human glial growth factor 2 (rhGGF2). Using primary rat Schwann cell cultures, we show that exogenous heparin and heparan sulfate block rhGGF2-induced phosphorylation of putative neuregulin receptors, and block subsequent DNA synthesis; other glycosaminoglycans show no such effect. Inhibition of Schwann cell HeSPG biosynthesis by administration of beta-xyloside also blocks responsiveness to rhGGF2. In cell-free binding assays, rhGGF2 binds heparin and heparan sulfate with high affinity, while suramin and suramin-like molecules block this binding. These suramin-like molecules reversibly block Schwann cell responsiveness to rhGGF2 with a rank order of potency identical to that in the cell-free binding assay. Thus we demonstrate high affinity and specificity in the interaction of rhGGF2 with heparin-like molecules, and show that three distinct perturbations of this interaction on Schwann cells (exogenous heparin/ heparan sulfate treatment, inhibition of HeSPG biosynthesis, and treatment with suramin-like molecules) result in a loss of responsiveness to rhGGF2. These results support a model in which HeSPGs are critical components that modulate extracellular rhGGF2 signaling interactions with appropriate receptor tyrosine kinases.
Automotive engine combustion with excess air. Interim progress report, Jul 1974--Sep 1975 (1975)

Lean burn, stratified charge, and Diesel engines all involve combustion in the presence of excess air. All have a potential for improved efficiency with lower emissions, in comparison with the conventional spark-ignition engines. An experimental laboratory study of combustion with excess air under conditions simulating the reciprocating engine environment has been initiated. A single pulse, compression-expansion machine has been designed, fabricated, and assembled. Initial cold (without combustion) experiments have been conducted to determine flow patterns within the combustor with particular attention to the phenomenon of vortex rollup. In support of the single pulse combustor effort, a number of theoretical, experimental, and engine tasks have been undertaken and are briefly reported in this interim progress report. (GRA)
A low-limit estimate of average distance between conjugate points on a geodesic with random curvature (2007)

The minimum distance between conjugate points on a geodesic with the curvature given by a random renewal process is estimated. It is shown that, in the zero-curvature limit, the problem is reduced to analysis of the intersection of the level by a certain diffusion process with reflection.
Supplementary figures and legends from Matrix Stiffening and EGFR Cooperate to Promote the Collective Invasion of Cancer Cells (2023)

&lt;p&gt;Supplemental data&lt;/p&gt;
Photoperiodic regulation of hippocampal neurogenesis in adult male white‐footed mice (Peromyscus leucopus) (2014)

Photoperiodic organisms monitor environmental day length to engage in seasonally appropriate adaptions in physiology and behavior. Among these adaptations are changes in brain volume and neurogenesis, which have been well described in multiple species of birds, yet few studies have described such changes in the brains of adult mammals. White-footed mice (Peromyscus leucopus) are an excellent species in which to investigate the effects of day length on adult hippocampal neurogenesis, as males, in addition to having reduced hippocampal volume in short days (SD) with concomitant impairments in hippocampus-mediated behaviors, have photoperiod-dependent changes in olfactory bulb neurogenesis. We performed the current experiment to assess the effects of photoperiod on hippocampal neurogenesis longitudinally, using the thymidine analog bromodeoxyuridine at multiple time points across 10 weeks of SD exposure. Compared with counterparts held in long day (LD) lengths, across the first 8 weeks of SD exposure hippocampal neurogenesis was reduced. However, at 10 weeks in SD lengths neurogenic levels in the hippocampus were elevated above those levels in mice held in LD lengths. The current findings are consistent with the natural photoperiodic cycle of hippocampal function in male white-footed mice, and may help to inform research on photoperiodic plasticity in neurogenesis and provide insight into how the complex interplay among the environment, genes and adaptive responses to changing day lengths affects brain structure, function and behavior at multiple levels.
Integration of BST thin film for DRAM fabrication (1995)

Abstract A process technique to integrate the sputter-deposited BST thin film into the DRAM is discussed. With some reconsiderations concerning the grain structure of the BST, the care of the electrode edge, the thermal stability of the capacitor characteristic, the upper dielectric of the capacitor and so on, the BST was successfully integrated into a capacitor TEG structure on a 9Mbits scale. By using the newly developed integration technique, a 4MDRAM was fabricated, exhibiting the normal bit function with a wide margin. After this, improvements on the thermal stability are needed by developing a barrier layer under the bottom Pt electrode that is more heat-resistant than currently achieved.
Efficient Agroinfiltration of Plants for High-level Transient Expression of Recombinant Proteins (2013)

Mammalian cell culture is the major platform for commercial production of human vaccines and therapeutic proteins. However, it cannot meet the increasing worldwide demand for pharmaceuticals due to its limited scalability and high cost. Plants have shown to be one of the most promising alternative pharmaceutical production platforms that are robust, scalable, low-cost and safe. The recent development of virus-based vectors has allowed rapid and high-level transient expression of recombinant proteins in plants. To further optimize the utility of the transient expression system, we demonstrate a simple, efficient and scalable methodology to introduce target-gene containing Agrobacterium into plant tissue in this study. Our results indicate that agroinfiltration with both syringe and vacuum methods have resulted in the efficient introduction of Agrobacterium into leaves and robust production of two fluorescent proteins; GFP and DsRed. Furthermore, we demonstrate the unique advantages offered by both methods. Syringe infiltration is simple and does not need expensive equipment. It also allows the flexibility to either infiltrate the entire leave with one target gene, or to introduce genes of multiple targets on one leaf. Thus, it can be used for laboratory scale expression of recombinant proteins as well as for comparing different proteins or vectors for yield or expression kinetics. The simplicity of syringe infiltration also suggests its utility in high school and college education for the subject of biotechnology. In contrast, vacuum infiltration is more robust and can be scaled-up for commercial manufacture of pharmaceutical proteins. It also offers the advantage of being able to agroinfiltrate plant species that are not amenable for syringe infiltration such as lettuce and Arabidopsis. Overall, the combination of syringe and vacuum agroinfiltration provides researchers and educators a simple, efficient, and robust methodology for transient protein expression. It will greatly facilitate the development of pharmaceutical proteins and promote science education.
Self-doped polyaniline and polypyrrole. A comparative study by X-ray photoelectron spectroscopy (1991)

Polymer communications Guildford
ald of Mycobacterium tuberculosis Encodes both the Alanine Dehydrogenase and the Putative Glycine Dehydrogenase (2011)

The putative glycine dehydrogenase of Mycobacterium tuberculosis catalyzes the reductive amination of glyoxylate to glycine but not the reverse reaction. The enzyme was purified and identified as the previously characterized alanine dehydrogenase. The Ald enzyme was expressed in Escherichia coli and had both pyruvate and glyoxylate aminating activities. The gene, ald, was inactivated in M. tuberculosis, which resulted in the loss of all activities. Both enzyme activities were found associated with the cell and were not detected in the extracellular filtrate. By using an anti-Ald antibody, the protein was localized to the cell membrane, with a smaller fraction in the cytosol. None was detected in the extracellular medium. The ald knockout strain grew without alanine or glycine and was able to utilize glycine but not alanine as a nitrogen source. Transcription of ald was induced when alanine was the sole nitrogen source, and higher levels of Ald enzyme were measured. Ald is proposed to have several functions, including ammonium incorporation and alanine breakdown.
Solar Landfills: Economic, Environmental, and Social Benefits (2017)

Abstract Ideally suited for hosting large solar photovoltaic arrays feeding electricity into the grid, closed landfills will play a significant role in the undergoing energy transition from fossil‐fuel and nuclear energy to renewable energy. Aimed at sustainability scholars and policy makers, this study identifies the economic, environmental, and social benefits of solar landfills, suggesting avenues for the massive transformation of hazardous landfills into renewable‐energy‐generation plants. Thus, the landfills no longer pose threats to human health and to the ecosystem.
Metal Ni-loaded g-C3N4for enhanced photocatalytic H2evolution activity: the change in surface band bending (2015)

A series of Ni@g-C3N4 composites were synthesized by a simple solvent thermal method using melamine and acetylacetone nickel as precursors. The results of X-ray diffraction, transmission electron microscopy and high resolution transmission electron microscopy indicate that Ni was successfully loaded on g-C3N4. And the Ni loaded greatly enhances the photocatalytic H2 evolution activity of g-C3N4 compared to the pure g-C3N4. In order to study the role of Ni, the surface photovoltage, the surface photocurrent and photoluminescence measurements were used to investigate the photogenerated charge properties of g-C3N4. What is more, Mott-Schottky plots and work function measurements confirmed the surface band bending change of g-C3N4 contacting with Ni. Those results demonstrate that Ni coating deepens surface band bending of g-C3N4, resulting in higher separation efficiency of photogenerated charge carriers, which is contributed to the enhanced photocatalytic H2 evolution activity.
Hollow-core fibers with reduced surface roughness and ultralow loss in the short-wavelength range (2023)

While optical fibers display excellent performances in the infrared, visible and ultraviolet ranges remain poorly addressed by them. Obtaining better fibers for the short-wavelength range has been restricted, in all fiber optics, by scattering processes. In hollow-core fibers, the scattering loss arises from the core roughness and represents the limiting factor for loss reduction regardless of the cladding confinement power. Here, we report on the reduction of the core surface roughness of hollow-core fibers by modifying their fabrication technique. The effect of the modified process has been quantified and the results showed a root-mean-square surface roughness reduction from 0.40 to 0.15 nm. The improvement in the core surface entailed fibers with ultralow loss at short wavelengths. The results reveal this approach as a promising path for the development of hollow-core fibers with loss that can potentially be orders of magnitude lower than the ones achievable with silica-core counterparts.
Actin-activated Mg-ATPase activity of Dictyostelium myosin II. Effects of filament formation and heavy chain phosphorylation. (1992)

The actin-activated Mg-ATPase activities of unphosphorylated and heavy chain phosphorylated Dictyostelium myosin II and of a Dictyostelium myosin II heavy meromyosin (HMM) fragment were examined at different Mg2+ and KCl concentrations. The Mg-ATPase activity of HMM displayed a maximum rate, Vmax, of about 4.0/s and a Kapp (actin concentration required to achieve 1/2 Vmax) that increased from 8 to 300 microM as the KCl concentration increased from 0 to 120 mM. When assayed with greater than 5 mM Mg2+ and 0 mM KCl the unphosphorylated Dictyostelium myosin II yielded a Kapp of 0.25 microM and a Vmax of 2.8/s. At lower Mg2+ concentrations or with 50 mM KCl the data were not fit well by a single hyperbolic curve and Kapp increased to 25-100 microM. The increase in Kapp did not correlate with the loss of sedimentable filaments. At KCl concentrations above 100 mM Vmax increased to greater than 4/s. Heavy chain phosphorylated myosin (3.5 mol of phosphate/mol myosin) displayed a Vmax of about 5/s and a Kapp of 50 microM under all conditions tested. Thus, heavy chain phosphorylation inhibited the actin-activated Mg-ATPase activity of Dictyostelium myosin II in 5-10 mM Mg2+ and low ionic strength through an increase in Kapp.
Prolongation of Allograft Survival by Intrathymic Introduction of Allogeneic Thymic Epithelial Cells (2018)

Thymic epithelial cells (TECs), the primary stromal population in the thymus, are critical to establish the microenvironments required for generating self-tolerant, pathogen-responsive T cells. However, due to the inaccessibility of the thoracic cavity and the fragility of TECs, manipulating the thymus to modulate adaptive immune responses remains challenging. We developed a novel surgical procedure that allowed access to thymus glands for intrathymic injection (ITI), without the need to cut the manubrium of the sternum bone. Horizontal cuts of the muscle layers between the first and second bones of the rib cage expose the thymus with minimal side effects. This novel ITI procedure enabled us to implant 16.5-day embryonic TECs into an adult syngeneic recipients’ thymus. Long-term survival and colonization of the implanted TECs was observed via live imaging, flow cytometry, and immunohistochemistry. We further investigated if introduction of allogeneic TECs in the thymus promote negative selection against allo-reactive T cells and induce donor-specific immune tolerance. We engrafted B6 islets under the kidney capsules of chemically induced diabetic Balb/C mice, preconditioned with T-cell depletion sera and intrathymic injection of B6 16.5-day embryonic TECs. Prolonged survival of the transplanted islets was observed compared to sham-operated controls. Mixed lymphocyte reaction experiments further showed dampened T cell proliferation responses against donor B6 antigens. Moreover, increased levels of Foxp3+ T-regulatory cells were detected in Balb/C recipients with ITI of B6 TECs, suggesting that implanted TECs could also promote the generation of alloantigen-specific T regulatory cells in addition to facilitating negative selection of donor antigen-reactive T cells. Our results suggest that intrathymic transplantation of TECs could be an effective way to induce donor-specific immune tolerance with limited general immune suppression. Disclosure I. Pradhan: None. S. Wong-Noonan: None. S. Bertera: None. R.J. Lakomy: None. H. Cohen: None. D. Wells: None. M. Trucco: None. Y. Fan: None.
Replication Protein A Blocks the Way (2017)

ADVERTISEMENT RETURN TO ISSUEViewpointNEXTReplication Protein A Blocks the WayEric C. Greene*View Author Information Department of Biochemistry & Molecular Biophysics, Columbia University, New York, New York 10032, United States*E-mail: [email protected]Cite this: Biochemistry 2017, 56, 13, 1809–1810Publication Date (Web):March 23, 2017Publication History Received10 March 2017Published online23 March 2017Published inissue 4 April 2017https://pubs.acs.org/doi/10.1021/acs.biochem.7b00221https://doi.org/10.1021/acs.biochem.7b00221editorialACS PublicationsCopyright © 2017 American Chemical Society. This publication is available under these Terms of Use. Request reuse permissions This publication is free to access through this site. Learn MoreArticle Views1045Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail PDF (147 KB) Get e-AlertscloseSUBJECTS:Adducts,DNA replication,Fluorescence resonance energy transfer,Genetics,Peptides and proteins Get e-Alerts
Multimode dynamics of terahertz quantum cascade lasers: Spontaneous and actively induced generation of dense and harmonic coherent regimes (2022)

We present a study concerning the dynamics of dense and harmonic coherent regimes in quantum cascade lasers (QCLs) in a Fabry--Perot configuration emitting in the terahertz (THz) spectral region. Firstly, we study the device in free-running operation, reproducing the main features of the self-generated optical frequency combs and harmonic frequency combs in this spectral range, commenting on the points of difference from the midinfrared region and finding excellent agreement with the most recent experimental evidence. Then, we analyze the THz-QCL dynamics under radio-frequency injection, with a focus on the effect of the modulation of the current on the degree of locking of the system, and we perform a systematic investigation aimed to provide a procedure for the generation of a train of pulses with short duration and high contrast. Furthermore, we extend our study to the generation of sequences of pulses with repetition frequency, which is a multiple of the free-spectral range (FSR) of the laser cavity, reproducing harmonic mode locking of the laser, a method which has been recently demonstrated in experiments with THz QCLs, and the results of which are particulary promising for a large stream of applications ranging from optical communication to imaging.
Evaluation of Prime/Boost Regimens Using Recombinant Poxvirus/Tyrosinase Vaccines for the Treatment of Patients with Metastatic Melanoma (2006)

Whereas prime/boost immunization with recombinant vaccinia and fowlpox viruses enhanced antityrosinase immunity in some patients with metastatic melanoma, it was ineffective alone in mediating clinical benefit, and in combination with IL-2 did not mediate clinical benefit significantly different from that expected from treatment with IL-2 alone.
DEPTOR: A Novel Cell‐Intrinsic Molecule That Plays A Critical Role In The Regulation Of Endothelial Activation, Proinflammatory And Angiogenic Responses (2013)

Cytokine‐mediated activation of endothelial cells (EC) is characteristic of immune inflammation, and therapeutics that inhibit EC activation have broad implications for the treatment of chronic diseases. Here, by qPCR and Western blot analyses, we find that DEPTOR, an intracellular inhibitor of mTOR signaling, is expressed in vascular EC. Using a siRNA knockdown approach and phosphokinase arrays, we found that DEPTOR functions to inhibit the mTOR, ERK1/2 and STAT1 signaling pathways in EC. Moreover, using pharmacological inhibitors of mTOR (Rapamycin, Torin1) and ERK1/2 (U0126), we found that DEPTOR regulates each of these pathways through independent mechanisms. Importantly, we also found that knockdown of DEPTOR in EC results in marked activation responses, including up to an ~1000 fold increase in the mRNA expression of T cell chemokines (CXCL9, CXCL10, CXCL11, CX3CL1 and CCL5) and adhesion molecules (VCAM‐1 and ICAM‐1). Functionally, we also found that DEPTOR siRNA transfected EC, a) bind increased numbers of PBMC and CD3+ T cells (P&lt;0.005) in adhesion assays and b) have increased migration and angiogenic responses (P&lt;0.01) in the wound healing and spheroid sprouting assays. Collectively, these findings identify DEPTOR as a novel regulatory molecule in EC, and suggest that its relative level of expression is of great importance in EC‐dependent mechanisms of inflammation and in immune angiogenesis.
Terahertz transparency at Fabry-Perot resonances of periodic slit arrays in a metal plate (2007)

We report on a terahertz transparency in periodic arrays of metallic slits using terahertz time- domain spectroscopy. Experimental results and theoretical calculations reveal that Fabry-Perot resonance appearing in spectral region below first Rayleigh minimum strongly enhances terahertz transmission and a symmetric eigenmode inside the slits is excited under the condition of terahertz transparency.