gebhart/patrepeval huggingface dataset:
A Conserved Amphipathic Helix in the N-Terminal Regulatory Region of the Papillomavirus E1 Helicase Is Required for Efficient Viral DNA Replication (2011)

The papillomavirus E1 helicase, with the help of E2, assembles at the viral origin into a double hexamer that orchestrates replication of the viral genome. The N-terminal region (NTR) of E1 is essential for DNA replication in vivo but dispensable in vitro, suggesting that it has a regulatory function. By deletion analysis, we identified a conserved region of the E1 NTR needed for efficient replication of viral DNA. This region is predicted to form an amphipathic α-helix (AH) and shows sequence similarity to portions of the p53 and herpes simplex virus (HSV) VP16 transactivation domains known as transactivation domain 2 (TAD2) and VP16C, which fold into α-helices upon binding their target proteins, including the Tfb1/p62 (Saccharomyces cerevisiae/human) subunit of general transcription factor TFIIH. By nuclear magnetic resonance (NMR) spectroscopy and isothermal titration calorimetry (ITC), we found that a peptide spanning the E1 AH binds Tfb1 on the same surface as TAD2/VP16C and with a comparable affinity, suggesting that it does bind as an α-helix. Furthermore, the E1 NTRs from several human papillomavirus (HPV) types could activate transcription in yeast, and to a lesser extent in mammalian cells, when fused to a heterologous DNA-binding domain. Mutation of the three conserved hydrophobic residues in the E1 AH, analogous to those in TAD2/VP16C that directly contact their target proteins, decreased transactivation activity and, importantly, also reduced by 50% the ability of E1 to support transient replication of DNA in C33A cells, at a step following assembly of the E1-E2-ori preinitiation complex. These results demonstrate the existence of a conserved TAD2/VP16C-like AH in E1 that is required for efficient replication of viral DNA.
A Comprehensive Study of the Analysis and Economic Benefits of Radioactive Tracer Engineered Stimulation Procedures (1995)

Abstract Hydraulic Fracturing is an important technology to enhance production from tight gas reservoirs. Several techniques have been utilized to attempt to evaluate the effectiveness of hydraulic fracturing treatments. One technique, radioactive tracers, is currently used on over 15% of the stimulation treatments performed in the U.S. With proper materials, design, and execution, tracers can be used to locate the presence and concentration of proppant at the wellbore in order to evaluate vertical and radial proppant distribution. A comprehensive study of over 100 fracture treatments has been completed in which radioactive tracers were used along with production logs, stress logs, post-fracturing completion reports, and production history to analyze completion effectiveness in four different reservoirs. Additionally, an economic benefit model was constructed to evaluate the benefit/cost ratio of applying the technology.
Physical Properties of Ammonia Solutions. Ammonium Nitrate-Ammonia-Water and Urea-Ammonia-Water. (1952)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPhysical Properties of Ammonia Solutions. Ammonium Nitrate-Ammonia-Water and Urea-Ammonia-Water.E. A. Worthington, R. C. Datin, and D. P. SchutzCite this: Ind. Eng. Chem. 1952, 44, 4, 910–913Publication Date (Print):April 1, 1952Publication History Published online1 May 2002Published inissue 1 April 1952https://pubs.acs.org/doi/10.1021/ie50508a054https://doi.org/10.1021/ie50508a054research-articleACS PublicationsRequest reuse permissionsArticle Views321Altmetric-Citations11LEARN 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 Other access options Get e-Alerts
Wafer Level Electromigration Tests for Production Monitoring (1985)

Smaller geometrics are requiring metal lines to carry higher current densities. This increases their susceptibility to electromigration. This paper describes the SWEAT test (Standard Wafer-level Electromigration Acceleration Test) which was developed to monitor electromigration susceptibility at the wafer level. The test is extremely fast, allowing evaluation of a metal line in less than 15 seconds. It also uses a specially designed test structure to concentrate those stresses which lead to voiding. Most importantly, this test allows the user to derate data obtained to give equivalent lifetimes the same as those obtained in conventional testing.
Demonstration of Directional Modulation Using a Phased Array (2010)

A four-symbol modulation is created by repeated switching of phase shifters in a phased array, in a technique known as directional modulation (DM). The phase shifts are chosen to minimize the bit error rate (BER) in a line-of-sight channel in a desired direction while maximizing the BER elsewhere. A DM transmitter is demonstrated in an anechoic chamber, and results are compared with a traditional baseband QPSK modulation using the same phased array. Experiments indicate that the DM transmitter creates a narrower region of low BERs around the desired direction than the traditional phased array while maintaining high BERs in the sidelobe regions.
Potential role of leptin in angiogenesis: leptin induces endothelial cell proliferation and expression of matrix metalloproteinases in vivo and in vitro (2001)

Leptin, the product of ob gene, is an endocrine hormone that regulates adipose tissue mass. Recently, leptin has been found to generate a growth signal involving a tyrosine kinase-dependent intracellular pathway and promote angiogenic processes via activation of leptin receptor (Ob-R) in endothelial cells. However, it is not clear how leptin functions to promote multi-step processes involved in the neovascularization at the atherosclerotic plaque. We have examined the expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) and Ob-R in human atherosclerotic lesions, leptin-mediated angiogenesis in vivo and in vitro. Immunohistochemical analysis of human atherosclerotic aorta revealed an increased expression of Ob-R in the intima of neorevascularized regions and of both MMPs and TIMPs predominantly in the endothelial lining of intimal neovessels and macrophages/foam cells. In the rat corneal angiogenesis assay, leptin elicited a comparable sensitivity of angiogenic activity to those of vascular endothelial growth factor (VEGF). The immunohistological analysis of the leptin-treated rat cornea showed definitive rises in Ob-R, MMPs and TIMPs expression as well as those of VEGF receptor (VEGFR-1). Leptin (10-40 ng/ml) induced proliferation of the human umbilical vein endothelial cells (HUVECs) and elevation of MMP-2, MMP-9, TIMP-1, and TIMP-2 expression in a dose-dependent manner. Leptin also induced increases of MMP-2, MMP-9, TIMP-1, and Up-regulated the human coronary artery smooth muscle cells (HCASMCs). These findings suggest that leptin, a hormone with pluralistic properties including a mitogenic activity on vascular endothelial cells, plays a role in matrix remodeling by regulating the expression of MMPs and TIMPs. Taken together, our findings further provide evidences for leptin's role as an angiogenesis inducer in the normal organ (rat cornea) and in aberrant vasculature under duress like atherosclerosis.
A Selective C and L-Band Amplified Spontaneous Emission Source Using a 1×2 Optical Switch (2005)

We report on a band selective amplified spontaneous emission (ASE) source of an erbium-doped fibre (EDF), which can operate in either the C- or L-band region. The band selective ASE source is realized using a pump conversion technique by a 1×2 optical switch, which makes the ASE source design convert between a backward and a forward pumped configuration alternately. A heavily doped erbium fibre and a 1480 nm laser diode are adopted for this design synchronously to enhance the power of L-band ASE. A power of 16.2 mW for C-band ASE and 11.8 mW for L-band ASE are obtained with a total pump power of 100 mW.
ZnO nanocones and nanoplatelets: synthesis and characterization (2010)

Nanowire structure plays an important role in the development of nanotechnology. However, further study shows that the shape of nanowires may not be the ideal morphology for some applications such as solar cells and sensors. Thus, the purpose of this thesis is to find a low cost and high yield approach to the synthesis of other morphologies of nanostructures in order to further improve the performance of these nanodevices. \n\nTo this end, a chemical approach has been extended to the synthesis ZnO nanocones and platelets. With UV illumination, the synthesis of ZnO nanocones was achieved on GaN films on sapphire and gold films on silicon substrates. Both TEM and XRD results show that as-grown ZnO nanocones are single crystals. The formation of ZnO nanocones could be explained by the absorption process of photons. The UV light induced thermal gradient modifies the heat distribution as well as the reagent transport. The chemical reaction system is kinetically limited and results in ZnO nanocones. If the UV light is blocked, the ZnO nanowires result. In addition, the density of ZnO nanocones is higher than ZnO nanowires grown without UV illumination. \n\nBy this chemical approach, ZnO platelets could also be obtained on GaN films deposited by PLD, whose c-axis is parallel to the surface of the substrate. The diameters and the thickness of the platelets depend on the quality and thickness of GaN film. TEM results illustrate that the obtained ZnO platelets are single crystals grown along the <0 1 1 0> direction within the {0 0 0 1} planes. Relative growth rates of various facets were altered by the presence of [1 0 0] textured GaN film. The suppression of the growth along c axis can also be achieved by citrate anions as a structure-directing agent to adsorb selectively on ZnO basal planes. Electrical measurement shows that the resistance of ZnO platelets is about 20-40 GΩ¸ and it is higher than that of ZnO nanowires. Piezoelectric potential calculation results also indicate that the piezoelectric potential is higher than for ZnO nanowires with the same external applied stress.\n\nThese procedures and results demonstrate an easy and low cost way to fabricate ZnO nanocones and platelets, which may aid the utilization of nanostructures in solar cells, sensors and other applications to further improve their performance.
Cadmium telluride semiconductor detector for improved spatial and energy resolution radioisotopic imaging (2017)

The detector in single-photon emission computed tomography has played a key role in the quality of the images. Over the past few decades, developments in semiconductor detector technology provided an appropriate substitution for scintillation detectors in terms of high sensitivity, better energy resolution, and also high spatial resolution. One of the considered detectors is cadmium telluride (CdTe). The purpose of this paper is to review the CdTe semiconductor detector used in preclinical studies, small organ and small animal imaging, also research in nuclear medicine and other medical imaging modalities by a complete inspect on the material characteristics, irradiation principles, applications, and epitaxial growth method.
Structure and Dynamics of <sup>13</sup>C,<sup>15</sup>N‐Labeled Lipopolysaccharides in a Membrane Mimetic (2008)

The natural look of endotoxin: A new approach has been developed to determine the chemical structure, dynamics, and conformation of lipopolysaccharide (endotoxin, see structure) by solution NMR spectroscopy. Using isotope labeling and solubilization by dihexanoylphosphatidylcholine as a mimetic of the bacterial membrane, a general approach makes complex endotoxin molecules amenable to analysis by heteronuclear NMR methods. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
Interference between Two Specific Pathogen Recognition Events Mediated by Distinct Plant Disease Resistance Genes. (1996)

We demonstrate that the interaction of the avirulence gene avrRpt2 and the cognate resistance gene RPS2 interferes with the interaction of avrRpm1-RPM1 in Arabidopsis. Interference is mediated outside of the bacterial pathogen Pseudomonas syringae, presumably at the level of recognition of avr-dependent signals, yet does not require the wild-type RPS2 product. A numerical excess of P. syringae expressing avrRpm1 can overcome this interference in mixed inoculations. The interference of avrRpt2-RPS2 engagement with RPM1-dependent functions is mirrored by transcriptional activation of genes preferentially expressed during RPM1- or RPS2-mediated disease resistance reactions. This demonstration of interference between two plant disease resistance genes suggests that their products compete for a common element(s) in a signal transduction pathway leading to disease resistance.
Understanding power system stability (2005)

This paper discusses the causes of power system instability and the importance of fast fault clearing. The k-constant model is used to explain the relationships among the following: small signal stability, high impedance transmission lines, line loading and high gain, fast acting excitation systems. Various types of power system instability, utilizing both mathematical and practical approaches, are covered. Transient stability is discussed, including synchronizing and damping torques. The power angle curve is used to illustrate how fault clearing time and high initial response excitation systems can affect transient stability. In the past number of years, "power system stability" has become an increasingly popular term used in generation and transmission. The sudden requirement for power system stabilizers for use with new and existing excitation equipment has created much confusion about their applicability, purpose, and benefit to the power system. This paper will discuss the fundamentals of the power system stabilizer and its effectiveness in the system. An explanation will be provided concerning the various types of power system stabilizers and the benefit of some types over others. Lastly, the paper will address regulatory commission guidelines identified by NERC that will impact generation connected to the transmission system.
Deformation Pattern of Twisted Nematic Liquid Crystal Layers in an Electric Field (1974)

Abstract At rest between two metallized glass plates a nematic liquid shows a screw-like deformation pattern if one turns the plates by an angle ωm around an axis perpendicular to the plates. If a voltage U is applied, the molecules are tilted with respect to the electric field when U exceeds a threshold voltage. With increasing amount of twist ωm the maximum angle of tilt γ m increases to almost π/2 even in a weak field. Numerical results are given for the Schadt-Helfrich-cell, i.e. ωmλπ/2. The effect of piezc-electricity on deformation in a Schadt-Helfrich-cell is discussed.
Kinetics and Energetics of Assembly, Nucleation, and Growth of Aggregates and Fibrils for an Amyloidogenic Protein (2002)

The transition states for prenucleation assembly, nucleation, and growth of aggregates and amyloid fibrils were investigated for a dimeric immunoglobulin light chain variable domain, employing pressure, temperature, and solutes as variables. Pressure-induced aggregation was nucleation-dependent and first-order in protein concentration and could be seeded. The insoluble aggregates were mixtures of amyloid fibrils and amorphous aggregates. Activation volumes, activation surface areas, and activation waters of hydration were larger for aggregate growth than for prenucleation assembly or nucleation, although activation free energies were similar for the three processes. Activation free energies for each of the transition states were dominated by the unfavorable free energy of solvation of newly exposed surfaces. Equilibrium dissociation and unfolding of the dimer showed a much larger volume change than those required to form the transition states for the three processes. Thus, the transition states for these steps are similar to the native state, and their formation requires only small structural perturbations. Finally, the presence of Congo red during amyloid fibril formation shortened lag times and caused pressure insensitivity of nucleation, suggesting that this compound or its analogs may not be effective as inhibitors of amyloidosis.
"Learning the kernel" through examples: an application to shape classification (2002)

One important problem in any retrieval system is the design of good features and of good similarity measures between features. Usually these similarity functions are defined through ad-hoc distances between features. We propose a new way to design such distances, based on non-rigid deformation of nonlinear principal components, in the framework of semi-parametric statistical regression. The proposed approach is applied to the construction of new rotation invariant distance between planar curves.
People and communities in mountain tourism: overview, contextual development and areas of focus. (2016)

This chapter introduces Part III of the book, which explores various aspects of people and communities that reside in or visit mountain tourism environments. A contextual background of the relevant literature related to people and communities provides an introduction and understanding of the importance of the diverse challenges facing planners, developers, operators, community participants, and other relevant mountain tourism stakeholders. Engagement and collaboration strategies that focus on the variety of needs and interests found in mountain tourism are included.
Effect of Surface Structure on the Irreversible Capacity of Various Graphitic Carbon Electrodes (1999)

In order to understand the structural effect on irreversible capacity, the electrochemical lithium intercalation of various graphitic carbons was studied in 1 M solution of ethylene carbonate/propylene carbonate/diethyl carbonate (EC/PC/DEC), as a function of PC content. Because the irreversible capacity was increased by PC only for the carbons with a considerable edge fraction, it was possible to selectively amplify and monitor the reaction on the edge surface. The important role of the edge surface was confirmed qualitatively by high resolution transmission electron microscope images of the surface structure and quantitatively by further analysis on the results, using a simple model that explicitly considered the different reactivity of EC and PC toward the basal and edge surfaces. Exfoliation behavior, emerging as the PC content increased above a certain structure‐dependent threshold, was examined also. The structural effect could be explained by assuming that the cointercalation of PC gave rise to exfoliation. Two controlling factors were suggested: the structural integrity affecting the expansion of layer spacing and the geometry of the edge surface affecting the cointercalation of PC. © 1999 The Electrochemical Society. All rights reserved.
Cryptosporidia--who is at risk? (1995)

Cryptosporidium parvum is a coccidian parasite originally described a century ago and, until recently, not considered to be a human pathogen. It has a complex life cycle, including both sexual and asexual reproduction, an auto-infectious cycle, and the ability to complete its development within a single host. The transmission form is a robust, environmentally resistant oocyst, excreted in the stool, which can exist for long periods of time in the environment. Because animals, in particular domesticated livestock, are its primary host, human infection is usually zoonotic. Oocysts often find their way into water supplies, and it resists chlorination and is incompletely filtered from processed drinking water supplies, even when filtration is working optimally. Transmission via ingestion of fecally contaminated swimming pool water, food, fomites, and sexual activities facilitating fecal-oral inoculation have been demonstrated. The major target of C. parvum in the host is the intestinal epithelial cell, resulting in diarrhea, sometimes profuse and persistent, although it may also infect other organs such as the gall bladder and lungs. Pathogenesis involves attachment, probably via a sporozoite lectin, invasion, probably involving apical organelles, replication within a parasitophorous vacuole with the host cell membrane, causing cellular dysfunction. Diagnosis is generally made by visualization of the oocyst form in stool by staining methods, the best of which appears to be auramine and fluorescence microscopy. Those at greatest risk are immunocompromised adults and children, especially those with AIDS, children in day care, travelers to endemic regions, dairy or cattle farm workers of their families or contacts, household contacts of cases or carriers, and possibly owners of infected dogs or cats or their neighbors. There is no specific therapy available, however in the immunocompetent host the illness is self-limited, lasting from a few days to 3 weeks, and long term carriage is uncommon. In the immunocompromised host, infection is prolonged, sometimes asymptomatic, but may result in chronic debilitating diarrhea with dehydration, malabsorption and wasting. Public health measures to reduce contamination of water supplies and vigilant surveillance will reduce the risk to populations. Reducing behaviors favoring fecal-oral transmission, such as certain sexual activities, and scrupulous hygiene in the day care setting would also reduce the likelihood of transmission but not eliminate it. Given our lack of knowledge about Cryptosporidium biology and pathogenesis, high priority should be given to research designed to increase our understanding of the organism and improve the chance of developing useful therapeutic or preventative drugs or strategies.
Human DNA-(Cytosine-5) Methyltransferase-PCNA Complex as a Target for p21 <sup>WAF1</sup> (1997)

DNA-(cytosine-5) methyltransferase (MCMT) methylates newly replicated mammalian DNA, but the factors regulating this activity are unknown. Here, MCMT is shown to bind proliferating cell nuclear antigen (PCNA), an auxiliary factor for DNA replication and repair. Binding of PCNA requires amino acids 163 to 174 of MCMT, occurs in intact cells at foci of newly replicated DNA, and does not alter MCMT activity. A peptide derived from the cell cycle regulator p21(WAF1) can disrupt the MCMT-PCNA interaction, which suggests that p21(WAF1) may regulate methylation by blocking access of MCMT to PCNA. MCMT and p21(WAF1) may be linked in a regulatory pathway, because the extents of their expression are inversely related in both SV40-transformed and nontransformed cells.