gebhart/patrepeval huggingface dataset:
Advanced Glycation End Product Precursors Impair ABCA1-Dependent Cholesterol Removal From Cells (2005)

Abnormal HDL metabolism may contribute to the increased atherosclerosis associated with diabetes. The ATP-binding cassette transporter A1 (ABCA1) is an atheroprotective cell protein that mediates cholesterol transport from cells to apolipoprotein (apo) A-I, the major protein in HDL. Because formation of advanced glycation end products (AGEs) is associated with diabetic vascular complications, we examined the effects of carbonyls implicated in AGE formation on the ABCA1 pathway in cultured fibroblasts and macrophages. Treating cells with glycolaldehyde (GA) and glyoxal (GO) strongly inhibited ABCA1-dependent transport of cholesterol from cells to apoA-I, while methylglyoxal had little effect. This occurred under conditions where other lipoprotein receptors or lipid metabolic pathways were little affected, indicating that ABCA1 was uniquely sensitive to these carbonyls. GA and GO destabilized ABCA1 and nearly abolished its binding of apoA-I, indicating that these carbonyls directly modified ABCA1. Immunohistology of coronary arteries from hyperlipidemic swine revealed that inducing diabetes with streptozotocin increased atherosclerotic lesion area and dramatically reduced the fraction of macrophages that expressed detectable ABCA1. These results raise the possibility that reactive carbonyl-mediated damage to ABCA1 promotes accumulation of cholesterol in arterial macrophages and thus contribute to the increased cardiovascular disease associated with diabetes, insulin resistance, and other inflammatory conditions.
Prostaglandin H synthase kinetics. The effect of substituted phenols on cyclooxygenase activity and the substituent effect on phenolic peroxidatic activity. (1992)

A series of p- and m-substituted phenols were examined for their effect on the cyclooxygenase activity of prostaglandin H synthase in 0.1 M phosphate buffer at pH 8.0 and 25.0 +/- 0.1 degrees C. A biphasic response was observed. At low concentrations phenols stimulate, but at higher concentrations inhibit, cyclooxygenase activity. Both enhancement and inhibition are increased by phenolic substituents which are electron-donating, quantified by Hammett sigma constants, and hydrophobic, quantified by Hantsch tau constants. The same series of substituted phenols was also reacted with compound II of prostaglandin H synthase at 4.0 +/- 0.5 degrees C. The compound II data fit the Hammett rho sigma equation; no hydrophobicity factors are required. Phenols inhibit cyclooxygenase activity by interfering with the binding of arachidonic acid to compound I and by competing directly with arachidonic acid as reducing substrates for compound I. Phenols stimulate cyclooxygenase activity by acting as reducing substrates for compound II, thereby accelerating the peroxidatic cycle. Phenols also protect the enzyme from self-catalyzed inactivation, most likely by removing the free radical of prostaglandin G2 by reducing it to prostaglandin G2. Kinetic parameters Km and kcat for cyclooxygenase activity were determined in the presence of phenols. Identical values of Km (15.3 +/- 0.5 mM) and kcat (89 +/- 2 s-1) were obtained regardless of which phenol was employed. Therefore these represent the true Km and kcat values for cyclooxygenase activity.
The properties of mica‐filled polypropylenes (1984)

Abstract Water‐ground Phlogopite micas were classified into narrow particle‐size distributions containing flakes with well‐defined diameters and thicknesses in order to evaluate the influence of particle size and flake aspect ratio on the mechanical properties of mica‐filled polypropylenes, For the purposes of comparison, most of the injection‐molded specimens contained 40 percent (by weight) mica. As expected, the flexural and tensile modulus values increased in proportion to the aspect ratio over the range from 30 to 60 to a maximum of 8 GPa. The measured tensile strengths of the mica‐filled polypropylenes increased substantially as the flake diameter became smaller, but did not correlate with the flake aspect ratio. The attainable properties were frequently dependent upon the method of mixing, and considerable care was necessary to ensure proper dispersion and adequate coupling. Intensive mixing, as in a Gelimat Mixer, may cause in situ delamination and particle‐size reduction of the mica filler particles, leading to a marked increase in tensile strength of the resulting composite. The mica‐filled compounds could be reprocessed many times without significant loss of properties, particularly compounds having mica particles less than 40 μm in diameter. The fracture energies (notched Izod) and the heat‐distortion temperatures were not appreciably influenced by the size or aspect ratios of the mica within this range. Increased fracture toughness could be achieved by reducing the mica concentration or employing a polypropylene copolymer. Guidelines are presented to indicate the preferred characteristics of mica fillers and the influence of mixing conditions on performance.
Acoustic radiation force impulse of the liver (2013)

Acoustic radiation force impulse (ARFI) imaging is a new and promising ultrasound-based diagnostic technique that, evaluating the wave propagation speed, allows the assessment of the tissue stiffness. ARFI is implemented in the ultrasound scanner. By short-duration acoustic radiation forces (less than 1 ms), localized displacements are generated in a selected region of interest not requiring any external compression so reducing the operator dependency. The generated wave scan provides qualitative or quantitative (wave velocity values) responses. Several non-invasive methods for assessing the staging of fibrosis are used, in order to avoid liver biopsy. Liver function tests and transient elastography are non-invasive, sensitive and accurate tools for the assessment of liver fibrosis and for the discrimination between cirrhotic and non-cirrhotic liver. Many published studies analyse ARFI performance and feasibility in studying diffuse liver diseases and compare them to other diagnostic imaging modalities such as conventional ultrasonography and transient elastography. Solid focal liver lesions, both benign and malignant, are common findings during abdominal examinations. The accurate characterization and differential diagnosis are important aims of all the imaging modalities available today. Only few papers describe the application of ARFI technology in the study of solid focal liver lesions, with different results. In the present study, the existing literature, to the best of our knowledge, about ARFI application on diffuse and focal liver pathology has been evaluated and results and statistical analyses have been compared, bringing to the conclusion that ARFI can be used in the study of the liver with similar accuracy as transient elastography in diagnosing significant fibrosis or cirrhosis and has got some advantages in respect to transient elastography since it does not require separate equipment, better displays anatomical structures and measurements can be successfully carried out almost in every patient.
Catadioptric retroreflector (2011)

This paper proposes a new design for a retroreflector consisting of a biconvex lens with concentric surfaces, the back one having a mirror surface. Based on a calculation of the third-order aberrations and diffraction, calculated by means of the Fresnel–Kirchhoff integral in the Fraunhofer approximation, the influence of the length of the retroreflector on the axial luminous intensity is investigated.
Exercise training prevents the exaggerated exercise pressor reflex in rats with chronic heart failure (2010)

An exaggerated exercise pressor reflex (EPR) occurs in the chronic heart failure (CHF) state, which contributes to exercise intolerance and excessive sympathoexcitation during exercise. Exercise training (ExT) improves abnormal cardiovascular reflexes in CHF. Whether ExT can normalize the exaggerated EPR function remains to be determined. This study was designed to investigate the effects of ExT on the EPR and on the mechanical or metabolic components of this reflex in sham-operated and CHF rats. The EPR was activated by static contraction induced by electrical stimulation of L4/L5 ventral roots. The afferent fibers associated with the mechanoreflex and metaboreflex were activated by passive stretch and hindlimb arterial injection of capsaicin (0.1 and 1 microg/kg, 0.2 ml), respectively. Heart rate, blood pressure, and sympathoexcitatory responses during the activation of these reflexes were compared in sham+sedentary (Sed), sham+ExT, CHF+Sed, and CHF+ExT rats. Compared with sham+Sed rats, CHF+Sed rats exhibited exaggerated heart rate and pressor and sympathoexcitatory responses to either static contraction or passive stretch, whereas the cardiovascular responses to injection of capsaicin were blunted. Eight to ten weeks of ExT normalized the exaggerated responses induced by static contraction or passive stretch and partially improved the blunted responses due to intra-arterial capsaicin in CHF rats. ExT had no significant effect on the EPR and mechanoreflex and metaboreflex functions in sham rats. These findings suggest a potential therapeutic role for ExT in minimizing arterial pressure and sympathetic outflow following activation of the EPR in the CHF state.
Total Synthesis of the Death Cap Toxin Phalloidin: Atropoisomer Selectivity Explained by Molecular‐Dynamics Simulations (2019)

Phallotoxins and amatoxins are a group of prominent peptide toxins produced by the death cap mushroom Amanita phalloides. Phalloidin is a bicyclic cyclopeptide with an unusual tryptathionin thioether bridge. It is a potent stabilizer of filamentous actin and in a fluorescently labeled form widely used as a probe for actin binding. Herein, we report the enantioselective synthesis of the key amino acid (2S,4R)-4,5-dihydroxy-leucine as a basis for the first total synthesis of phalloidin, which was accomplished by two different synthesis strategies. Molecular-dynamics simulations provided insights into the conformational flexibility of peptide intermediates of different reaction strategies and showed that this flexibility is critical for the formation of atropoisomers. By simulating the intermediates, rather than the final product, molecular-dynamics simulations will become a decisive tool in orchestrating the sequence of ring formation reactions of complex cyclic peptides.
Effects of a novel cholinergic M1 agonist, AF102B, on ambulation and water drinking behavior in rats. (1991)

Effects of a novel M1 agonist, AF102B (cis-2-methylspiro(1,3-oxathiolane-5,3')quinuclidine HCl), on ambulation and water drinking behavior were examined using an Ambulo-Drinkometer. AF64A-treated rats, an animal model for senile dementia of the Alzheimer type (SDAT), and non-treated control rats were used. AF102B was administered orally via tap water at a concentration of 0.01% and 0.1% for an experimental therapeutic dose and a supramaximal dose, respectively. Four-week administration of 0.01% AF102B did not affect either ambulatory activity or water drinking activity in non-treated rats. Successive 0.1% AF102B administration for 4 weeks produced a significant decrease in drinking activity as compared with non-treated control rats. In AF64A-treated rats, AF102B did not change the cholinotoxin AF64A-induced high activity in ambulation. However, a decrease in water drinking activity was observed after 0.1% AF102B administration, as in non-treated rats. These results suggest that therapeutic dose of AF102B do not produce any changes in the spontaneous moter activity and water drinking behavior in normal rats or the animal model for SDAT. Several investigators reported that AF102B (FSK-508; cis-2-methylspiro (1,3-oxathiolane-5,3') quinuclidine HCl) had the property of a relatively specific muscarinic agonist of the M1-type This novel M1 agonist, AF102B, also exerted and ameliorating effect on experimental amnesia; in a T-maze, radial-arm maze task and passive avoidance tasks. AF102B improves the cognitive impairment in various animal models for memory disorders including senile dementia of the Alzheimer type (SDAT). Based on these observations, AF102B has been proposed for the treatment of SDAT.(ABSTRACT TRUNCATED AT 250 WORDS)
Preparation and Solubility in Acid and Water of Partially Deacetylated Chitins (2000)

Partially deacetylated chitins with different degrees of deacetylation (DD) were prepared by alkaline treatment under homogeneous conditions, and the effect of DD on their solubility was discussed in terms of crystal structure and mode of hydrogen bonding. With an increase in the treatment time, the DD of chitin increased proportionally. The chitin became soluble in dilute acetic acid at the DD of ca. 28% or over and soluble in water at the DD of ca. 49%. The solubility of the partially deacetylated chitins had a close relationship with their crystal structure, crystallinity, and crystal imperfection as well as the glucosamine content. The wide-angle X-ray diffractometry (WAXD) revealed that the chitin with ca. 28% DD retained the crystal structure of alpha-chitin with significantly reduced crystallinity and perfection of the crystallites. The water-soluble chitin of ca. 49% DD had a new crystal structure similar to that of beta-chitin rather than either alpha-chitin or chitosan, suggesting that the homogeneous deacetylation transformed the crystal structure of chitin from the alpha to the beta form. Some hydrogen bonds existing in raw alpha-chitin were found to be missing at a DD of ca. 49%.
Seasonal and inter‐annual variation in diet for gray wolves <i>Canis lupus</i> in Prince Albert National Park, Saskatchewan (2020)

Plains bison Bison bison bison were extirpated from most of their historical range in the late nineteenth century, and few studies have examined the interactions of bison with gray wolves Canis lupus . The Sturgeon River plains bison (SRPB) population in Prince Albert National Park, Saskatchewan is one of only a few populations of plains bison in their historical range in Canada and have declined around 50% since 2005. This study examined the inter‐ and intra‐annual variation in wolf diet using stable isotope analysis (SIA), to assess the importance of bison and other ungulates to wolf diet relative to the decline of the SRPB. We used wolf hair (n = 35) and blood (n = 29) collected from 30 individuals from 2011 to 2017 to estimate the diet of two packs for summer and winter, and visited potential wolf kill sites (n = 270) during the winter from 2013 to 2017 to collect prey samples. We used wolf scats (n = 465) collected in the winter and summer of 2012–2013 as priors for our Bayesian stable isotope mixing models. We found the percentage of bison (median range: 26–39%), deer/elk (21–24%) and moose (16–33%) consumed in the summer was consistently high, compared to winter when white‐tailed deer Odocoileus virginianus comprised the highest percentage of wolf diet (40–49%). We observed small inter‐annual variation in wolf diet. We examined differences between packs and found that wolves that had greater overlap with the SRPB had more bison in their diet, particularly in winter (26–40%). Results from SIA were consistent with percentages of prey found at wolf kill sites. Overall, bison constitute a lower proportion of wolf diet compared to other wild ungulates, and our findings support the assumption that wolf predation is not the main contributing factor to SRPB population decline.
Carbon nanotube growth for through silicon via application (2013)

Through silicon via (TSV) technology is key for next generation three-dimensional integrated circuits, and carbon nanotubes (CNT) provide a promising alternative to metal for filling the TSV. Three catalyst preparation methods for achieving CNT growth from the bottom of the TSV are investigated. Compared with sputtering and evaporation, catalyst deposition using dip-coating in a FeCl2 solution is found to be a more efficient method for realizing a bottom-up filling of the TSV (aspect ratio 5 or 10) with CNT. The CNT bundles grown in 5 min exceed the 50 μm length of the TSV and are multi-wall CNT with three to eight walls. The CNT bundles inside the TSV were electrically characterized by creating a direct contact using a four-point nanoprober setup. A low resistance of the CNT bundle of 69.7 Ω (297 Ω) was measured when the CNT bundle was contacted midway along (over the full length of) the 25 μm deep TSV. The electrical characterization in combination with the good filling of the TSV demonstrates the potential use of CNT in fully integrated TSV applications.
Accurate, Compact, and Power-Efficient Li-Ion Battery Charger Circuit (2006)

A novel, accurate, compact, and power-efficient lithium-ion (Li-Ion) battery charger designed to yield maximum capacity, cycle life, and therefore runtime is presented and experimentally verified. The proposed charger uses a diode to smoothly (i.e., continuously) transition between two high-gain linear feedback loops and control a single power MOS device, automatically charging the battery with constant current and then constant voltage. An adaptive power-efficient charging scheme in the form of a cascaded switching regulator supply ensures the voltage across the charging power-intensive pMOS remains low, thereby reducing its power losses and yielding up to 27% better overall power efficiency. An 83% power-efficient printed circuit board prototype was built and used to charge several Li-Ion batteries to within plusmn0.43% of their optimum full-charge voltage and therefore within a negligibly small fraction of their full capacity
A structured approach to the selection of condition based maintenance (1997)

Condition based maintenance (CBM) triggers maintenance activity on a parameter which is indicative of machine health. Regular tasks, which are the staple of planned preventive maintenance become scheduled inspections and measurements rather than repair or replacements, and actions are only scheduled when they are really needed. It is important that CBM is applied to appropriate problems in plant, rather than as an overall policy. The first stages of the structured approach define the problems from failure history and plant criticality. Plant criticality, in terms of safety, capital value, and influence on value of production, determines areas which are likely to be cost effective. Management evaluation and control aims to maximise cost effectiveness by regular review of selection of plant and techniques. This paper details a structured method for achieving the above, which combines a theoretical model with practical experience, and describes successful applications in the automotive industry and in the building services sector.
Unslotted 1- and p/sub i/-persistent CSMA-CD protocols for fiber optic bus networks (1994)

Analyzes the performance of the unslotted 1-persistent carrier sense multiple access with collision detection (CSMA-CD) protocol for fiber optic bus networks with a finite number of stations M, each of which has an infinite storage buffer for storing packets with its length fixed or exponentially distributed. Treating the bus network as an M-class priority queueing system with a preemptive repeat-identical retransmission strategy, the authors show numerically that this 1-persistent retransmission strategy provides better delay-throughput performance than the non-persistent one. To satisfy the fairness of equal delays among stations in the bus network, the authors next present the unslotted p/sub i/-persistent CSMA-CD protocol. Under this protocol, the first packet arriving at station i is forced to enter into the backoff procedure with the probability of (1/spl minus/p/sub i/). After backoffs, transmission begins until the station becomes empty. The authors determine the persistent probability p/sub i/ and show that the delay-throughput performance of the p/sub i/-persistent strategy is better than that of the 1-persistent one, and further it is robust for any packet lengths. Simulation results are presented to verify the analytical results.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Cytolytic T-lymphocyte responses to respiratory syncytial virus: effector cell phenotype and target proteins (1990)

Cytolytic T-lymphocyte (CTL) activity specific for respiratory syncytial (RS) virus was investigated after intranasal infection of mice with RS virus, after intraperitoneal infection of mice with a recombinant vaccinia virus expressing the F glycoprotein, and after intramuscular vaccination of mice with Formalin-inactivated RS virus or a chimeric glycoprotein, FG, expressed from a recombinant baculovirus. Spleen cell cultures from mice previously infected with live RS virus or the F-protein recombinant vaccinia virus had significant CTL activity after one cycle of in vitro restimulation with RS virus, and lytic activity was derived from a major histocompatibility complex-restricted, Lyt2.2+ (CD8+) subset. CTL activity was not restimulated in spleen cells from mice that received either the Formalin-inactivated RS virus or the purified glycoprotein, FG. The protein target structures for recognition by murine CD8+ CTL were identified by using target cells infected with recombinant vaccinia viruses that individually express seven structural proteins of RS virus. Quantitation of cytolytic activity against cells expressing each target structure suggested that 22K was the major target protein for CD8+ CTL, equivalent to recognition of cells infected with RS virus, followed by intermediate recognition of F or N, slight recognition of P, and no recognition of G, SH, or M. Repeated stimulation of murine CTL with RS virus resulted in outgrowth of CD4+ CTL which, over time, became the exclusive subset in culture. Murine CD4+ CTL were highly cytolytic for RS virus-infected cells, but they did not recognize target cells infected with any of the recombinant vaccinia viruses expressing the seven RS virus structural proteins. Finally, the CTL response in peripheral blood mononuclear cells of adult human volunteers was investigated. The detection of significant levels of RS virus-specific cytolytic activity in these cells was dependent on at least two restimulations with RS virus in vitro, and cytolytic activity was derived primarily from the CD4+ subset.
Infant mortality statistics from the 2005 period linked birth/infant death data set. (2008)

The U.S. infant mortality rate was 6.86 infant deaths per 1,000 live births in 2005, which is statistically unchanged from 6.78 in 2004. Infant mortality rates ranged from 4.89 deaths per 1,000 live births for Asian or Pacific Islander (API) mothers to 13.63 for non-Hispanic black mothers. Among Hispanics, rates ranged from 4.42 for Cuban mothers to 8.30 for Puerto Rican mothers. Infant mortality rates were higher for infants who were born in multiple deliveries or whose mothers were born in the 50 states and the District of Columbia or were unmarried. Infant mortality was also higher for male infants and infants born preterm or at low birthweight. The neonatal mortality rate was essentially unchanged from 2004 (4.52) to 2005 (4.54). The postneonatal mortality rate increased 3 percent from 2.25 in 2004 to 2.32 in 2005. Infants born at the lowest gestational ages and birthweights have a large impact on overall U.S. infant mortality. For example, more than one-half (55 percent) of all infant deaths in the United States in 2005 occurred to the 2 percent of infants born very preterm (less than 32 weeks of gestation). Infant mortality rates for late preterm infants (34-36 weeks of gestation) were three times those for term infants (37-41 weeks). The three leading causes of infant death--congenital malformations, low birthweight, and sudden infant death syndrome (SIDS)--accounted for 44 percent all infant deaths. The percentage of infant deaths that were "preterm-related" increased from 34.6 percent in 2000 to 36.5 percent in 2005. The preterm-related infant mortality rate for non-Hispanic black mothers was 3.4 times higher and the rate for Puerto Rican mothers was 87 percent higher than the rate for non-Hispanic white mothers.