gebhart/patrepeval huggingface dataset:
Telomere shortening and ageing of the immune system. (2008)

Telomeres are protein-DNA complexes localized at the ends of linear chromosomes constituted by short, tandem G-rich hexanucleotide repeats and associated proteins. Their length shortens with each cell division and correlates inversely with age. It can be modified by genetic and epigenetic factors, sex hormones, reactive oxygen species and inflammatory reactions. A critical minimum length of telomeres triggers a cell cycle arrest or senescence of the cell. The immune system is highly sensitive to shortening of telomeres as its competence depends strictly on cell renewal and clonal expansion of T- and B-cell populations. Cells of the immune system are unique among normal somatic cells as they can up-regulate telomerase, the telomere extending enzyme, and limit telomere attrition in the process of cell proliferation undergoing in activated cells. Telomere length is highly variable among humans. Lineage-specific telomere shortening with different kinetics of telomere attrition was observed in CD4+, CD8+ T lymphocytes, B lymphocytes, granulocytes, monocytes and NK cell population. Immunosenescence is characterized by a special remodeling of the immune system induced by antigen exposure and oxidative stress. In ageing immune system adaptive immunity deteriorates because of a progressive decline of naive T and B cells and decrease of absolute numbers of T and B lymphocytes. The innate compartment of the immune system is relatively well preserved although some age-dependent alterations can be also observed. Nonagenarians or centenarians represent phenomenon of successful ageing of the immune system as most of their immune parameters are well preserved.
A Microwave Feed-Forward Experiment (1971)

Both one- and two-stage feed-forward control were applied to α 4-GHz, 461A, traveling-wave tube, used in the TD-3 radio relay system, to demonstrate the feasibility of reducing distortion to a sufficiently low level for single sideband transmission. With a single stage, and discounting extraneous losses, the third-order, MS, distortion measure was reduced by 38 dB over a selected 20-MHz channel, and the application of the second stage rendered distortion unobservable with our instruments. These results were time independent with continuous performance over several months.
Improvement of rotor position angle estimation in SRD using fuzzy logic based motor model (2004)

In this paper, a novel method of sensorless rotor position angle estimation based on the knowledge of motor model and the relation of /spl Psi/-I-/spl theta/ is developed on using fuzzy logic based motor model. Due to electromagnetic interference and measurement error, there are more errors in result. In order to improve the precision of the method, a predictive module is added in system. Through comparing predicted value with estimated value, more accurate value is gotten in test. The result shows that, with improved estimation system, rotor position angle can be accurately estimated in different regions, including startup, low-speed and mid-speed region.
Genome Sequence of the Obligate Methanotroph <i>Methylosinus trichosporium</i> Strain OB3b (2010)

Methylosinus trichosporium OB3b (for "oddball" strain 3b) is an obligate aerobic methane-oxidizing alphaproteobacterium that was originally isolated in 1970 by Roger Whittenbury and colleagues. This strain has since been used extensively to elucidate the structure and function of several key enzymes of methane oxidation, including both particulate and soluble methane monooxygenase (sMMO) and the extracellular copper chelator methanobactin. In particular, the catalytic properties of soluble methane monooxygenase from M. trichosporium OB3b have been well characterized in context with biodegradation of recalcitrant hydrocarbons, such as trichloroethylene. The sequence of the M. trichosporium OB3b genome is the first reported from a member of the Methylocystaceae family in the order Rhizobiales.
Impaired Binding of the Age-related Macular Degeneration-associated Complement Factor H 402H Allotype to Bruch's Membrane in Human Retina (2010)

Age-related macular degeneration (AMD) is the predominant cause of blindness in the industrialized world where destruction of the macula, i.e. the central region of the retina, results in loss of vision. AMD is preceded by the formation of deposits in the macula, which accumulate between the Bruch's membrane and the retinal pigment epithelium (RPE). These deposits are associated with complement-mediated inflammation and perturb retinal function. Recent genetic association studies have demonstrated that a common allele (402H) of the complement factor H (CFH) gene is a major risk factor for the development of AMD; CFH suppresses complement activation on host tissues where it is believed to bind via its interaction with polyanionic structures. We have shown previously that this coding change (Y402H; from a tyrosine to histidine residue) alters the binding of the CFH protein to sulfated polysaccharides. Here we demonstrate that the AMD-associated polymorphism profoundly affects CFH binding to sites within human macula. Notably, the AMD-associated 402H variant binds less well to heparan sulfate and dermatan sulfate glycosaminoglycans within Bruch's membrane when compared with the 402Y form; both allotypes exhibit a similar level of binding to the RPE. We propose that the impaired binding of the 402H variant to Bruch's membrane results in an overactivation of the complement pathway leading to local chronic inflammation and thus contributes directly to the development and/or progression of AMD. These studies therefore provide a putative disease mechanism and add weight to the genetic association studies that implicate the 402H allele as an important risk factor in AMD.
Profiling of Endogenous Estrogens, Their Precursors, and Metabolites in Endometrial Cancer Patients: Association with Risk and Relationship to Clinical Characteristics (2011)

Background: Endometrial cancer (EC) predominantly occurs after menopause and is strongly related to steroid hormones, particularly estrogens. However, the relationship between these hormones and clinical characteristics remains unaddressed. Experimental Design: We analyzed the circulating levels of 18 steroids including adrenal precursors, androgens, estrogens, and their glucuronide metabolites, using specific and validated methods based on tandem mass spectrometry. Our goals were to compare circulating levels in postmenopausal women with EC (n = 126) with those of healthy postmenopausal women (n = 110) and to investigate how these hormonal levels relate to clinical characteristics. Results: After adjustment for potential confounders, most hormones were significantly elevated in EC patients compared with healthy controls. In women with type I cancer, estrogen levels were up to 3-fold those of healthy women (P &lt; 0.05). These higher levels were associated with an increased risk of cancer, particularly estrogens and their direct precursors, testosterone and androstenedione (odds ratios ranging from 4.4 to 13.3; P ≤ 0.0003). Elevated circulating levels of estrogens and their metabolites were found in cancer cases with type I endometrioid cancer and low-grade and noninvasive tumor, suggesting an association between these hormones and the tumoral estrogenic activity. In addition, levels of estrone sulfate in EC patients with relapse were 2-fold over levels of EC patients without relapse (P &lt; 0.05), and 4.5-fold over those of healthy women (P &lt; 0.001). Conclusions: Circulating levels of steroids were associated with increased risk of EC. Estrogens may represent novel biomarkers predictive of clinical characteristics, including evidence for an increased risk of relapse.
Long-term follow-up study of osseointegrated implants in the treatment of totally edentulous jaws. (1990)

This study reviews the long-term outcome of prostheses and fixtures (implants) in 759 totally edentulous jaws of 700 patients. A total of 4,636 standard fixtures were placed and followed according to the osseointegration method for a maximum of 24 years by the original team at the University of Göteborg. Standardized annual clinical and radiographic examinations were conducted as far as possible. A lifetable approach was applied for statistical analysis. Sufficient numbers of fixtures and prostheses for a detailed statistical analysis were present for observation times up to 15 years. More than 95% of maxillae had continuous prosthesis stability at 5 and 10 years, and at least 92% at 15 years. The figure for mandibles was 99% at all time intervals. Calculated from the time of fixture placement, the estimated survival rates for individual fixtures in the maxilla were 84%, 89%, and 92% at 5 years; 81% and 82% at 10 years; and 78% at 15 years. In the mandible they were 91%, 98%, and 99% at 5 years; 89% and 98% at 10 years; and 86% at 15 years. (The different percentages at 5 and 10 years refer to results for different routine groups of fixtures with 5 to 10, 10 to 15, and 1 to 5 years of observation time, respectively.) The results of this study concur with multicenter and earlier results for the osseointegration method.
Efficient, Repeated Adenovirus-Mediated Gene Transfer in Mice Lacking both Tumor Necrosis Factor Alpha and Lymphotoxin α (1998)

The efficiency of adenovirus-mediated gene transfer is now well established. However, the cellular and the humoral immune responses triggered by vector injection lead to the rapid elimination of the transduced cells and preclude any efficient readministration. The present investigation focuses on the role of tumor necrosis factor alpha (TNF-alpha), a proinflammatory cytokine, and the related cytokine lymphotoxin alpha (LTalpha), in mounting an immune reaction against recombinant adenovirus vectors. After gene transfer in the liver, mice genetically deficient for both cytokines (TNF-alpha/LTalpha-/-), in comparison with normal mice, presented a weak acute-phase inflammatory reaction, a reduction in cellular infiltrates in the liver, and a severely impaired T-cell proliferative response to both Adenoviral and transgene product antigens. Moreover, we observed a strong reduction in the humoral response to the vector and the transgene product, with a drastic reduction of anti-adenovirus immunoglobulin A and G antibody isotypes. In addition, the reduction in antibody response observed in TNF-alpha/LTalpha-/- and TNF-alpha/LTalpha+/- mice versus TNF-alpha/LTalpha+/+ mice links antibody levels to TNF-alpha/LTalpha gene dosage. Due to the absence of neutralizing antibodies, the TNF-alpha/LTalpha knockout mice successfully express a second gene transduced by a second vector injection. The discovery of the pivotal role played by TNF-alpha in controlling the antibody response against adenovirus will allow more efficient adenovirus-based strategies for gene therapy to be proposed.
Isometric Texture Mapping for Free‐form Surfaces (1997)

Texture mapping is a frequently exploited technique in computer graphics aimed at the emulation of high‐resolution details in surfaces. In this paper we present a distance‐ratios preservation method for bivariate raster texture mapping to free‐form surfaces in an arbitrarily precise manner. The proposed method reduces the original general problem of computing the inverse of a three‐dimensional parametric surface mapping into a problem of two‐dimensional image warping. Several examples that demonstrate the proposed approach are also provided.
Two pyridine derivatives as potential Cu(<scp>ii</scp>) and Zn(<scp>ii</scp>) chelators in therapy for Alzheimer's disease (2009)

Two pyridine derivatives, DMAP and ENDIP, have been investigated as possible metal chelators in the therapy of Alzheimer's disease. Their complex formation with Cu(ii) and Zn(ii) were characterised in detail. In the case of ENDIP a high stability tetradentate ML complex is formed at physiological pH both with Cu(ii) and Zn(ii). DMAP was found to be a weaker metal binder. At physiological pH, it forms a bidentate ML complex with Zn(ii) and MLH(-1) and ML(2) complexes with Cu(ii), depending on the metal ion to ligand ratio. Fluorescence spectroscopy and dynamic light scattering measurements proved that ENDIP effectively competes with aggregated amyloid-beta peptides (Abeta) for both Cu(ii) and Zn(ii) and thus is able to prevent the metal ion-induced amyloid aggregation and to resolubilise amyloid precipitates.
Parsing expression grammars (2004)

For decades we have been using Chomsky's generative system of grammars, particularly context-free grammars (CFGs) and regular expressions (REs), to express the syntax of programming languages and protocols. The power of generative grammars to express ambiguity is crucial to their original purpose of modelling natural languages, but this very power makes it unnecessarily difficult both to express and to parse machine-oriented languages using CFGs. Parsing Expression Grammars (PEGs) provide an alternative, recognition-based formal foundation for describing machine-oriented syntax, which solves the ambiguity problem by not introducing ambiguity in the first place. Where CFGs express nondeterministic choice between alternatives, PEGs instead use prioritized choice. PEGs address frequently felt expressiveness limitations of CFGs and REs, simplifying syntax definitions and making it unnecessary to separate their lexical and hierarchical components. A linear-time parser can be built for any PEG, avoiding both the complexity and fickleness of LR parsers and the inefficiency of generalized CFG parsing. While PEGs provide a rich set of operators for constructing grammars, they are reducible to two minimal recognition schemas developed around 1970, TS/TDPL and gTS/GTDPL, which are here proven equivalent in effective recognition power.
ASC-1, PAT2, and P2RX5 are cell surface markers for white, beige, and brown adipocytes (2014)

White, beige, and brown adipocytes are developmentally and functionally distinct but often occur mixed together within individual depots. To target white, beige, and brown adipocytes for diagnostic or therapeutic purposes, a better understanding of the cell surface properties of these cell types is essential. Using a combination of in silico, in vitro, and in vivo methods, we have identified three new cell surface markers of adipose cell types. The amino acid transporter ASC-1 is a white adipocyte-specific cell surface protein, with little or no expression in brown adipocytes, whereas the amino acid transporter PAT2 and the purinergic receptor P2RX5 are cell surface markers expressed in classical brown and beige adipocytes in mice. These markers also selectively mark brown/beige and white adipocytes in human tissue. Thus, ASC-1, PAT2, and P2RX5 are membrane surface proteins that may serve as tools to identify and target white and brown/beige adipocytes for therapeutic purposes.
Interendothelial Claudin-5 Expression Depends on Cerebral Endothelial Cell–Matrix Adhesion by β<sub>1</sub>-Integrins (2011)

The hypothesis tested by these studies states that in addition to interendothelial cell tight junction proteins, matrix adhesion by β(1)-integrin receptors expressed by endothelial cells have an important role in maintaining the cerebral microvessel permeability barrier. Primary brain endothelial cells from C57 BL/6 mice were incubated with β(1)-integrin function-blocking antibody (Ha2/5) or isotype control and the impacts on claudin-5 expression and microvessel permeability were quantified. Both flow cytometry and immunofluorescence studies demonstrated that the interendothelial claudin-5 expression by confluent endothelial cells was significantly decreased in a time-dependent manner by Ha2/5 exposure relative to isotype. Furthermore, to assess the barrier properties, transendothelial electrical resistance and permeability measurements of the monolayer, and stereotaxic injection into the striatum of mice were performed. Ha2/5 incubation reduced the resistance of endothelial cell monolayers significantly, and significantly increased permeability to 40 and 150 kDa dextrans. Ha2/5 injection into mouse striatum produced significantly greater IgG extravasation than the isotype or the control injections. This study demonstrates that blockade of β(1)-integrin function changes interendothelial claudin-5 expression and increases microvessel permeability. Hence, endothelial cell-matrix interactions via β(1)-integrin directly affect interendothelial cell tight junction claudin-5 expression and brain microvascular permeability.
Boiling Heat Transfer With Freon 11 (R11) in Brazed Aluminum, Plate-Fin Heat Exchangers (1983)

The results of laboratory experiments with Freon 11 (R11) flowing in an electrically heated, serrated-fin test section to measure local boiling coefficients over a wide range of vapor quality, with mass fluxes up to 150 kg/m2 s, heat fluxes to 4 kW/m2, and pressure from 3–7 bar, are reported. These low mass and heat fluxes reflect the industrial process application of these heat exchangers where exceedingly small temperature differences may exist between streams. Results are compared with the very similar boiling characteristics previously reported elsewhere for the same test section, with liquid nitrogen as a test fluid under comparable flow conditions. A simple method using the Reynolds number of the total flow regarded as a liquid has been used to correlate boiling heat transfer coefficients with quality for both fluids. The use of a liquid-film flow model to produce a nondimensional correlation connecting the Nusselt, Reynolds, and Prandtl numbers of the film is discussed.
An improved GaAs MESFET equivalent circuit model for analog integrated circuit applications (1987)

An improved equivalent circuit model of a gallium-arsenide (GaAs) MESFET that is optimized for the design and analysis of precision analog integrated circuits is described. These circuits entail different modeling requirements from digital or microwave circuits, for which existing equivalent circuit models are optimized. Improved techniques are presented to model the drain-to-source conductance, device capacitance, and the functional dependence of drain-to-source current.
Determination of polychlorinated biphenyls in waste oil by gas-liquid chromatography (1987)

A 0.1 g portion of waste oil is cleaned up by silica gel chromatography followed by dimethylformamide-hexane partitioning and chromatography on a de-activated neutral alumina column. The purified extract is examined for PCBs by either packed-column or capillary-column gas chromatography using either electon-capture or Hall electrolytic conductivity detectors. Recoveries at the 10 mg kg–1 level are in the range 66–98% and the coefficient of variation is typically 12%. A reporting limit of 5 mg kg–1 is readily attainable and PCBs can be detected down to about 1 mg kg–1.
Optimal design of spatial distribution networks (2006)

We consider the problem of constructing facilities such as hospitals, airports, or malls in a country with a nonuniform population density, such that the average distance from a person's home to the nearest facility is minimized. We review some previous approximate treatments of this problem that indicate that the optimal distribution of facilities should have a density that increases with population density, but does so slower than linearly, as the two-thirds power. We confirm this result numerically for the particular case of the United States with recent population data using two independent methods, one a straightforward regression analysis, the other based on density-dependent map projections. We also consider strategies for linking the facilities to form a spatial network, such as a network of flights between airports, so that the combined cost of maintenance of and travel on the network is minimized. We show specific examples of such optimal networks for the case of the United States.
Inhibition of Electrochemical Reactions at Gold Surfaces by Grafted, Highly Fluorinated, Hyperbranched Polymer Films (1997)

We report the synthesis and passivation properties of surface-grafted, highly fluorinated, hyperbranched poly(acrylic acid) (PAA) films that contain up to 50 atom % F. These films are very hydrophobic (water contact angle of up to 114°) and block electrochemical reactions on gold electrodes. Cyclic voltammetry in basic solution shows that while an electrode covered with a three-layer PAA (3-PAA) film mimics an assembly of microelectrodes, a fluorinated three-layer PAA (3-PAA/F) film blocks nearly all electron transfer to the gold surface. The charge transfer resistance of electrodes covered with a 3-PAA/F film is about 40 times greater than that for an electrode covered with a nonfluorinated 3-PAA film. 3-PAA/F films are initially 10 times more blocking than C16SH SAMs. Additionally, while the SAM is desorbed by electrochemical cycling, 3-PAA/F films are still highly blocking after ten potential sweeps over a 1.5 V range. Thus fluorinated PAA films are promising candidates for corrosion-inhibiting coatings.
The status of the White-headed Duck <i>Oxyura leucocephala</i> (1992)

Summary The former and current status of the White-headed Duck Oxyura leucocephala is reviewed on the basis of recent census data and a literature search. The current world wintering population is estimated at 19,000 birds, with the likelihood that additional birds occur in unsurveyed wetlands in Asia. The population wintering in Pakistan appears to be declining, but there is no good evidence of current decline elsewhere in the range. The population resident in Spain is increasing. The greatest threat to the species is considered to be the spread of the introduced North American Ruddy Duck O. jamaicensis from the U.K. to the continent. Hybrids between the two species are fertile and have already been seen in Spain.
Simultaneous Detection of Heavy Metals by Anodic Stripping Voltammetry Using Carbon Nanotube Thread (2014)

Abstract Carbon nanotube (CNT) threads are a type of CNT arrays that consist of super long CNTs. CNT threads inherit the advantages of CNTs, while avoiding the potential toxicity caused by individual CNTs. Electrodes based on CNT threads were fabricated and used for simultaneous detection of trace levels of Cu 2+ , Pb 2+ Cd 2+ and Zn 2+ by anodic stripping voltammetry (ASV). The detection limits are 0.27 nM, 1.5 nM, 1.9 nM and 1.4 nM for Cu 2+, Pb 2+ , Cd 2+ and Zn 2+ , respectively, in 0.1 M acetate buffer pH 4.5. The CNT thread electrode gives well‐defined, reproducible and sharp stripping signals for individual and simultaneous detection of heavy metals.
Some considerations for optimal efficiency and low noise in large power combiners (2001)

This paper examines some relationships between important design parameters in large combiner systems and key performance objectives such as power, efficiency, noise, and graceful degradation. Results are derived for the combining efficiency of general combiner systems, and used to contrast spatial and corporate combiners and identify optimum combiner topology for a given device technology. The influence of array size on excess phase noise is quantified and shown to decrease with increase numbers of devices. Results are also presented for the degradation in combining efficiency due to statistical variations in amplifier characteristics, appropriate to large combiners, showing that phase errors are the dominant factor in power degradation.