gebhart/patrepeval huggingface dataset:
Rheological properties of aqueous solutions of (1 leads to 3) (1 leads to 4)-beta-D-glucan from oats (Avena sativa L.). (1995)

The rheological behavior of partially hydrolyzed oat (1→3)(1→4)-β-D-glucan was compared to that of the original unhydrolyzed β-D-glucan. Flow and oscillatory shear measurements of the nonhydrolyzed sample in aqueous solution showed behavior typical of noninteracting polysaccharides, such as guar gum, in solution. The rheology of partially hydrolyzed samples shifted toward the more get-like behavior observed with polymers, which tend to aggregate and form a three-dimensional macromolecular network. The aggregation may arise from a tendency of the β-glucan to self-associate through cellulose-like sequences in the structure. However, the reason why this behavior was not observed with unhydrolyzed oat gum is not understood. It is unlikely that structural variations, such as the amount of cellulose-like sequences, accounted for the different rheology, because quantitative analysis of oligosaccharides released by lichenase evidenced only minor differences between intact oat β-glucan and hydrolyzed samples. A more likely explanation is that because of their lower molecular weight, the partially hydrolyzed molecules are more mobile and diffuse more easily. Hence, they have a greater probability of forming aggregates.
Lifebelt for UK Science (2010)

When the United Kingdom's coalition government, formed in May this year, proposed to eliminate the budget deficit by slashing annual public expenditures by more than £80 billion per year, there was anxiety about science funding. Would the United Kingdom follow the United States, France, and Germany (and the emerging economies of the Far East) and prioritize scientific research as part of its economic recovery and growth strategy? Or would it align with Spain and the Czech Republic, where these areas were cut? Two weeks ago, the Spending Review announced a “flat cash” science budget of £4.6 billion per year for the next 4 years (with no allowance for inflation). This gives the United Kingdom a fighting chance of preserving its science base. But major concerns remain.
Mechanism of the <i>Clostridium thermoaceticum</i> Pyruvate:Ferredoxin Oxidoreductase:  Evidence for the Common Catalytic Intermediacy of the Hydroxyethylthiamine Pyropyrosphate Radical (1997)

The cofactor content and mechanism of pyruvate:ferredoxin oxidoreductase (PFOR) are controversial. By using rapid freeze-quench EPR and stopped-flow spectroscopy, the elementary steps that constitute the first half-reaction of the Clostridiumthermoaceticum PFOR mechanism were elucidated. A hydroxyethyl-TPP (HE-TPP) radical was identified and characterized as a transient intermediate, and for the first time, the kinetic competence of this substrate-derived radical was demonstrated. When the C. thermoaceticum PFOR was reacted with pyruvate and CoA, it had a lifetime of only approximately 100 ms. The results described here suggest that this radical intermediate is often not detected in studies of alpha-ketoacid oxidoreductases because it rapidly decays. It is postulated here that the HE-TPP radical is an intermediate in the mechanism of all PFORs irrespective of the number of 4Fe-4S clusters and will be detected in all PFORs when rapid mixing methods are used. The C. thermoaceticum PFOR was shown to contain two 4Fe-4S clusters, as concluded earlier [Wahl, R. C., & Orme-Johnson, W. H. (1987) J. Biol. Chem. 262, 10489-10496]. The first reductive half-reaction was shown to involve the following steps: (i) reaction with pyruvate with PFOR to form the hydroxyethylidene-TPP intermediate; (ii) one-electron transfer to reduce one of the two Fe4S4 clusters and yield the HE-TPP radical; and, (iii) reaction with CoA resulting in formation of acetyl-CoA, rapid decay of the HE-TPP radical intermediate, and reduction of the second Fe4S4 cluster. Thus, at the end of the first half-reaction, the two Fe4S4 clusters are fully reduced. The rate of the third step was found to depend on the CoA concentration (k = 35 per s at saturating concentrations of CoA); however, in its absence, this step was slower by approximately 4400-fold.
Optimal pipelining in supercomputers (1986)

This paper examines the relationship between the degree of central processor pipelining and performance. This relationship is studied in the context of modern supercomputers. Limitations due to instruction dependencies are studied via simulations of the CRAY-1S. Both scalar and vector code are studied. This study shows that instruction dependencies severely limit performance for scalar code as well as overall performance. The effects of latch overhead are then considered. The primary cause of latch overhead is the difference between maximum and minimum gate propagation delays. This causes both the skewing of data as it passes along the data path, and unintentional clock skewing due to clock fanout logic. Latch overhead is studied analytically in order to lower bound the clock period that may be used in a pipelined system. This analysis also touches on other points related to latch clocking. This analysis shows that for short pipeline segments both the Earle latch and polarity hold latch give the same clock period bound for both single-phase and multi-phase clocks. Overhead due to data skew and unintentional clock skew are each added to the CRAY-1S simulation model. Simulation results with realistic assumptions show that eight to ten gate levels per pipeline segment lead to optimal overall performance. The results also show that for short pipeline segments data skew and clock skew contribute about equally to the degradation in performance.
Characterization of the extracellular lipase of Bacillus subtilis and its relationship to a membrane-bound lipase found in a mutant strain. (1979)

Bacillus subtilis CMK33 is a mutant that is more osmotically fragile than the wild type when it is converted to the protoplast form. The protoplasts of this mutant contain a membrane-bound lipase, which is not found in protoplasts of the wild type. Hydrolysis of the membrane lipid of mutant protoplasts by the lipase is the cause of their fragility. A protein found in the wild type organism specifically inhibits the lipase (Kent, C., and Lennarz, W. J. (1972) Proc. Natl. Acad. Sci. U. S. A. 69, 2793-2797). This paper reports that cultures of both mutant and wild type cells contain an extracellular lipase which accumulates during the logarithmic phase of growth. The extracellular activity appears to be induced by a component of the growth medium. The membrane-bound lipase of the mutant has been partially purified and its properties have been compared to those of the extracellular lipase of the wild type. Their properties and sensitivity to the wild type inhibitor are similar, which suggests that the two molecules are closely related. The subcellular location of the lipase in the mutant has been investigated and compared to the location of the membrane-bound portion of the lipase inhibitor in the wild type. The lipase is located almost exclusively in the cytoplasmic membrane and not in mesosomal vesicles. In contrast, the lipase inhibitor is located in both types of membranes and is more concentrated in mesosomal vesicles. Under appropriate conditions, the appearance of new extracellular lipase activity in mutant cultures is paralleled by the loss of an equivalent amount of lipase activity from protoplasts prepared from the cells. This suggests that the membrane-bound lipase may be an intermediate in the secretion of the extracellular lipase. Because of the mutation in B. subtilis CMK33, which results in the absence of the lipase inhibitor, this intermediate can be found in protoplasts of the mutant, although it is not detectable in the wild type. Consequently, the mutant may be useful in studies of the mechanism of secretion of exoenzymes by Bacilli.
Differences in the interaction of the polyene antibiotic amphotericin B with cholesterol- or ergosterol-containing phospholipid vesicles. A circular dichroism and permeability study (1983)

The selective toxicity of the polyene antibiotic amphotericin B between pathogenic eukaryotic organisms and animal cells has often been said to originate in the presence of ergosterol in fungal membranes instead of cholesterol, found in membranes of animal cells. We have tested this hypothesis by measuring the proton efflux induced by amphotericin B in egg yolk phosphatidylcholine small unilamellar vesicles. By measuring circular dichroism under the same conditions, we monitored the interaction of the antibiotic and its conformational changes. Sterol-free vesicles are sensitive to amphotericin B, but the sensitivity of sterol-containing vesicles is always greater and increasingly so with increasing sterol concentration. Ergosterol-containing vesicles are more sensitive than cholesterol-containing vesicles. On the other hand, numerous amphotericin B conformers can be detected in sterol-containing vesicles, depending upon both the concentration of sterol and the amphotericin B sterol ratio. It appears that one conformer, or maybe two at high amphotericin B concentration, is responsible for the induced permeability. From their circular dichroism spectra, these two conformers are the same in the presence of ergosterol or cholesterol. The concentration of amphotericin B necessary to obtain the two conformers is higher with cholesterol than with ergosterol, which agrees with the permeability results.
Optimal tuning of control gains for rigid tapping processes using a learning automata methodology (2015)

Rigid tapping is a novel tapping process and is extensively used to produce internal threads on a manufactured mechanical part because of its precise and efficient performances. However, it is difficult in practice to design control gains for controlling rigid tapping processes using systematic approaches because the operational environments in the rigid tapping processes are usually unknown and cannot be predicted or modeled precisely. Tuning a set of control gains that could achieve good tapping results in rigid tapping processes is therefore a great challenge for users. In this study, we investigate the use of the learning automata methodology in optimal tuning of the control gains of rigid tapping processes operated under unknown operational environments. The rigid tapping results achieved on a CNC tapping machine indicate that the developed learning automata tuning method (consists of two tuning phases) can effectively tune the optimal control gains. As compared to tapping results where the control gains are obtained from a manual, the developed tuning method provides optimal control gains so that the CNC tapping machine efficiently and precisely produces internal threads that pass thread gauge tests.
Presynaptic dysfunction in Huntington's disease (2010)

HD (Huntington's disease) is produced by the expression of mutant forms of the protein htt (huntingtin) containing a pathologically expanded poly-glutamine repeat. For unknown reasons, in HD patients and HD mouse models, neurons from the striatum and cerebral cortex degenerate and lead to motor dysfunction and dementia. Synaptic transmission in those neurons becomes progressively altered during the course of the disease. However, the relationship between synaptic dysfunction and neurodegeneration in HD is not yet clear. Are there early specific functional synaptic changes preceding symptoms and neurodegeneration? What is the role of those changes in neuronal damage? Recent experiments in a Drosophila model of HD have showed that abnormally increased neurotransmitter release might be a leading cause of neurodegeneration. In the present review, we summarize recently described synaptic alterations in HD animal models and discuss potential underlying molecular mechanisms.
Effects of d-<i>α</i>-Tocopherol Supplementation on Experimentally Induced Primate Atherosclerosis (1992)

Prevention and regression of induced atherosclerosis by d-α-tocopherol was investigated in 24 male M. fascicularis. One group received a basal diet, while three others consumed an atherogenic diet. Two of the latter groups also received tocopherol, one at the onset of the study (prevention) and the other after atherosclerosis was established by ultrasound evaluation (regression). Atherosclerosis was monitored over a 36-month period by duplex ultrasound imaging of the common carotid arteries. At termination, 24 arterial sites were examined for histopathology. In those animals receiving an atherogenic diet, mean percent ultrasound stenosis at 36 months posttreatment was lower in the tocopherol-supplemented groups (61 and 18%) than in the unsupplemented group (87%). Plasma tocopherol concentration was negatively correlated with percent ultrasound stenosis (p < 0.002). Percent stenosis in the regression group decreased from 33 to 8% (p < 0.05) 8 months after tocopherol supplementation. Although not consistently significant, histopathological changes were greater in untreated compared to treated animals. These results, if confirmed, indicate that d-α-tocopherol may be prophylactically and therapeutically effective in atherosclerosis.
Characterization of Urban Runoff Pollution between Dissolved and Particulate Phases (2013)

To develop urban stormwater management effectively, characterization of urban runoff pollution between dissolved and particulate phases was studied by 12 rainfall events monitored for five typical urban catchments. The average event mean concentration (AEMC) of runoff pollutants in different phases was evaluated. The AEMC values of runoff pollutants in different phases from urban roads were higher than the ones from urban roofs. The proportions of total dissolved solids, total dissolved nitrogen, and total dissolved phosphorus in total ones for all the catchments were 26.19%-30.91%, 83.29%-90.51%, and 61.54-68.09%, respectively. During rainfall events, the pollutant concentration at the initial stage of rainfall was high and then sharply decreased to a low value. Affected by catchments characterization and rainfall distribution, the highest concentration of road pollutants might appear in the later period of rainfall. Strong correlations were also found among runoffs pollutants in different phases. Total suspended solid could be considered as a surrogate for particulate matters in both road and roof runoff, while dissolved chemical oxygen demand could be regarded as a surrogate for dissolved matters in roof runoff.
Medicinal Chemistry and Pharmacology Focused on Cannabidiol, a Major Component of the Fiber-Type <i>Cannabis</i> (2013)

Considerable attention has focused on cannabidiol (CBD), a major non-psychotropic constituent of fiber-type cannabis plant, and it has been reported to possess diverse biological activities. Although CBD is obtained from non-enzymatic decarboxylation of its parent molecule, cannabidiolic acid (CBDA), several studies have investigated whether CBDA itself is biologically active. In the present report, the author summarizes findings indicating that; 1) CBDA is a selective cyclooxygenase-2 (COX-2) inhibitor, and ii) CBDA possesses an anti-migrative potential for highly invasive cancer cells, apparently through a mechanism involving inhibition of cAMP-dependent protein kinase A, coupled with an activation of the small GTPase, RhoA. Further, the author introduces recent findings on the medicinal chemistry and pharmacology of the CBD derivative, CBD-2',6'-dimethyl ether (CBDD), that exhibits inhibitory activity toward 15-lipoxygenase (15-LOX), an enzyme responsible for the production of oxidized low-density lipoprotein (LDL). These studies establish CBD as both an important experimental tool and as a lead compound for pharmaceutical development. In this review, the author further discusses the potential uses of CBD and its derivatives in future medicines.
A design methodology for implementing DSP with Xilinx/sup /spl reg// System Generator for Matlab/sup /spl reg// (2003)

This paper presents a methodology for implementing real-time DSP applications on a reconfigurable logic platform using Xilinx/sup /spl reg// System Generator for Matlab/sup /spl reg//. The methodology aims at improving the efficiency of learning the use of such complex design system. The methodology steps are demonstrated using DSP design examples built with Xilinx/sup /spl reg// System Generator for Matlab/sup /spl reg//. Assessment of the methodology is also discussed.
Moment tensor inversion of microseismic events from hydrofractures (1999)

PreviousNext No AccessSEG Technical Program Expanded Abstracts 1999Moment tensor inversion of microseismic events from hydrofracturesAuthors: Richard C. Nolen‐HoeksemaLarry J. RuffRichard C. Nolen‐HoeksemaUniversity of Michigan and Larry J. RuffUniversity of Michiganhttps://doi.org/10.1190/1.1820883 SectionsAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Permalink: https://doi.org/10.1190/1.1820883FiguresReferencesRelatedDetailsCited bySeismic imaging of hydraulically-stimulated fractures: A numerical study of the effect of the source mechanismAndrey H. Shabelansky, Alison Malcolm, Mike Fehler, and Sudhish K. Bakku25 October 2012Improved seismic identification of inter-fault damage via a linked geomechanics-seismic approach7 June 2022 | Geological Society, London, Special Publications, Vol. 289, No. 1 SEG Technical Program Expanded Abstracts 1999ISSN (print):1052-3812 ISSN (online):1949-4645Copyright: 1999 Pages: 2061 publication data© 1999 Copyright © 1999 Society of Exploration GeophysicistsPublisher:Society of Exploration Geophysicists HistoryPublished Online: 04 Jan 2005 CITATION INFORMATION Richard C. Nolen‐Hoeksema and Larry J. Ruff, (1999), "Moment tensor inversion of microseismic events from hydrofractures," SEG Technical Program Expanded Abstracts : 1779-1782. https://doi.org/10.1190/1.1820883 Plain-Language Summary PDF DownloadLoading ...
Applications of Carboxylic Acids in Organic Synthesis, Nanotechnology and Polymers (2018)

Carboxylic acids are versatile organic compounds. In this chapter is presented a current overview of the use of carboxylic acids in a different area as organic synthesis, nanotechnology, and polymers. The application carboxylic acids in these areas are: obtaining of small molecules, macromolecules, synthetic or natural polymers, modification surface of nanoparticles metallic, modification surface of nanostructure such as carbon nanotubes and graphene, nanomaterials, medical field, pharmacy, etc. Carboxylic acids can be natural and synthetic, can be extracted or synthesized, presented chemical structure highly polar, active in organic reactions, as substitution, elimination, oxidation, coupling, etc. In nanotechnology, the use of acid carboxylic as surface modifiers to promote the dispersion and incorporation of metallic nanoparticles or carbon nanostructure, in the area of polymer carboxylic acids present applications such monomers, additives, catalysts, etc. The purpose of this chapter is to emphasize the importance of carboxylic acids in different areas, highlighting the area of organic synthesis, nanotechnology and polymers and its applications.
Screening for Catastrophic Neck Injuries in Sports (2007)

The cervical spine is prone to injury due to the structure of the articulating vertebrae at the level of C4–C6, where the spinal cord occupies more of the spinal canal. Cervical spine injuries can occur in all sports and all ages. Participation in contact sports certainly increases the possibility of cervical spine injuries. In screening for catastrophic neck injuries it is vital to examine incidence and injury surveillance statistics in sports. These data can help determine sport-specific preponderance of catastrophic injury. Screening methods for predisposition to catastrophic cervical spine injuries include a concise history, physical examination, and radiographic methods. There is currently no universal classification system utilizing imaging of the cervical spine that has been validated as a screening method for catastrophic neck injuries.
A new versatile peroxidase from <i>Pleurotus</i> (2001)

Lignin peroxidase (LiP) and manganese peroxidase (MnP) have been investigated in Phanerochaete chrysosporium. A third ligninolytic peroxidase has been described in Pleurotus and Bjerkandera. Two of these versatile peroxidases (VPs) have been cloned, sequenced and characterized. They have high affinity for Mn(2+), hydroquinones and dyes, and also oxidize veratryl alcohol, dimethoxybenzene and lignin dimers. The deduced sequences show higher identity with Ph. chrysosporium LiP than MnP, but the molecular models obtained include a Mn(2+)-binding site. Concerning aromatic substrate oxidation, Pl. eryngii VP shows a putative long-range electron transfer pathway from an exposed trytophan to haem. Mutagenesis and chemical modification of this tryptophan and the acidic residues forming the Mn(2+)-binding site confirmed their role in catalysis. The existence of several substrate oxidation sites is supported further by biochemical evidence. Residue conservation in other fungal peroxidases is discussed.
Effects of Anabolic Precursors on Serum Testosterone Concentrations and Adaptations to Resistance Training in Young Men (2000)

The effects of androgen precursors, combined with herbal extracts designed to enhance testosterone formation and reduce conversion of androgens to estrogens was studied in young men. Subjects performed 3 days of resistance training per week for 8 weeks. Each day during Weeks 1, 2, 4, 5, 7, and 8, subjects consumed either placebo (PL; n = 10) or a supplement (ANDRO-6; n = 10), which contained daily doses of 300 mg androstenedione, 150 mg DHEA, 750 mg Tribulus terrestris, 625 mg Chrysin, 300 mg Indole-3-carbinol, and 540 mg Saw palmetto. Serum androstenedione concentrations were higher in ANDRO-6 after 2, 5, and 8 weeks (p <.05), while serum concentrations of free and total testosterone were unchanged in both groups. Serum estradiol was elevated at Weeks 2, 5, and 8 in ANDRO-6 (p <.05), and serum estrone was elevated at Weeks 5 and 8 (p <.05). Muscle strength increased (p <.05) similarly from Weeks 0 to 4, and again from Weeks 4 to 8 in both treatment groups. The acute effect of one third of the daily dose of ANDRO-6 and PL was studied in 10 men (23 +/- 4 years). Serum androstenedione concentrations were elevated (p <.05) in ANDRO-6 from 150 to 360 min after ingestion, while serum free or total testosterone concentrations were unchanged. These data provide evidence that the addition of these herbal extracts to androstenedione does not result in increased serum testosterone concentrations, reduce the estrogenic effect of androstenedione, and does not augment the adaptations to resistance training.
Tributylphosphine‐Catalyzed Ring‐Opening Reaction of Epoxides and Aziridines with Acetic Anhydride. (2003)

Abstract For Abstract see ChemInform Abstract in Full Text.
A Maximum Power Point Tracking System With Parallel Connection for PV Stand-Alone Applications (2008)

This paper presents the analysis, design, and implementation of a parallel connected maximum power point tracking (MPPT) system for stand-alone photovoltaic power generation. The parallel connection of the MPPT system reduces the negative influence of power converter losses in the overall efficiency because only a part of the generated power is processed by the MPPT system. Furthermore, all control algorithms used in the classical series-connected MPPT can be applied to the parallel system. A simple bidirectional dc-dc power converter is proposed for the MPPT implementation and presents the functions of battery charger and step-up converter. The operation characteristics of the proposed circuit are analyzed with the implementation of a prototype in a practical application.