gebhart/patrepeval huggingface dataset:
Regulation of valine catabolism by ammonium in<i>Streptomyces ambofaciens</i>, producer of spiramycin (1995)

In Streptomyces ambofaciens, valine favored spiramycin biosynthesis by supplying aglycone precursors. The kinetics of valine consumption and isobutyrate production showed that isobutyrate accumulated in the cell during the growth phase, was excreted in the stationary phase, and then was reassimilated during spiramycin production. When valine was in excess, its deamination led to high ammonium excretion and to a significant drop in spiramycin production. We demonstrated that ammonium ions were the cause of the negative effect. Addition of a chelator agent, Ca3(PO4)2, improved spiramycin production by sixfold. In contrast, addition of ammonium, between 0 and 48 h, severely reduced spiramycin production. The negative effect of ammonium was reversed by addition of a catabolic intermediate of valine, isobutyrate. In addition to stimulating the specific growth rate, ammonium ions slowed down valine catabolism: the specific valine uptake rate, excretion, and reassimilation of isobutyrate were lowered by the pulse of ammonium. Our study showed that in addition to valine dehydrogenase, which provided the nitrogen necessary to the cell, ammonium ions repressed ketoisovalerate dehydrogenase, which introduced valine as carbon, energy, and aglycone precursor sources. However, valine dehydrogenase and ketoisovalerate dehydrogenase did not constitute the principal enzymatic targets of the negative effect of ammonium in spiramycin production.
Pulse coded neural network implementation in VLSI (2002)

A neural network that encodes signals in terms of pulses has been designed and fabricated. The neural network components are described in detail. As a test case, a two-layer network is implemented. A preliminary test result shows some promise and some limitations of the design.
Low abdominal subcutaneous preadipocyte adipogenesis is associated with visceral obesity, visceral adipocyte hypertrophy, and a dysmetabolic state (2014)

Subcutaneous adipose tissue expansion through adipogenesis is increasingly recognized as a major determinant of body fat distribution and obesity-related cardiometabolic alterations. Our objective was to assess whether adipogenic rates of cultured human primary preadipocytes from the visceral and subcutaneous compartments relate to visceral obesity and cardiometabolic alterations. We recruited 35 women undergoing gynecological surgery and assessed body fat distribution by CT as well as fasting plasma lipids and glycemia. Fat samples from the greater omentum and abdominal subcutaneous (SC) compartments were used to assess mature adipocyte cell size and establish primary preadipocyte cultures. Differentiation was induced using adipogenic media and adipogenic rates were assessed using Oil Red O (ORO) absorbance/DNA content ratio and glyceraldehyde 3-phosphate dehydrogenase (G3PDH) activity/DNA of differentiated cells. We found a lower adipogenic capacity of omental (OM) preadipocytes than SC preadipocytes originating from the same women (P < 0.05). Whereas only OM cell size was different among groups of low vs high OM adipogenic rate, SC adipogenic rates were clearly related to increased OM cell size and dyslipidemia when women were separated on median value of either ORO/DNA or G3PDH activity/DNA ratios. When matched for BMI, women with low SC preadipocyte adipogenic rates had a higher visceral adipose tissue area (P < 0.01), omental adipocyte hypertrophy (P < 0.05), higher VLDL-lipid content (P < 0.01) and higher fasting glycemia (P < 0.05) than those with low SC adipogenic rates. In conclusion, low abdominal subcutaneous preadipocyte differentiation capacity in vitro is associated with visceral obesity, visceral adipocyte hypertrophy, and a dysmetabolic state.
VITREOUS BIOPSY IN UVEITIS OF UNKNOWN CAUSE (1981)

We employed vitreous biopsy (needle aspiration and pars plana vitrectomy) in eight cases of patients with uveitis of unknown etiology. The results of cytological and culture analysis provided the diagnosis of disseminated histoplasmosis in one patient and ocular reticulum cell sarcoma in another patient. In six patients, no specific, treatable causative agents or conditions were identified. In two of these patients, however, various etiologic agents were ruled out, which provided a basis for excluding certain therapeutic options. Where chronic inflammatory cells were seen in the vitreous, the patients responded satisfactorily to conventional therapy; patients with acute or mixed acute and chronic inflammatory cells did less well. No complications resulted from the biopsy procedure. In cases of uveitis of unknown etiology, vitreous biopsy may provide identification of specific causative agents, as well as information useful for more precise histopathologic grouping of entities in this disease.
Update on the use of fibrates: focus on bezafibrate (2008)

Abstract: Low-density lipoprotein-cholesterol (LDL-C) is a well established coronary heart disease (CHD) risk factor. However, the ability of this metabolic risk factor alone to identify individuals at risk for future CHD events is limited. The raised triglycerides-low high-density lipoprotein-cholesterol (HDL-C) dyslipidemia was shown to be an important cardiovascular risk factor independently of LDL-C levels. Fibric acid derivatives (fibrates) have been used in clinical practice for more than 2 decades as a class of agents known to decrease triglyceride levels while substantially increasing HDL-C levels. Through peroxisome proliferator-activated α-receptors, fibrates have a significant impact on the synthesis of several apolipoproteins and enzymes of lipoprotein metabolism as well as on the expression of several genes involved in fibrinolysis and inflammation. Data from recent primary and secondary prevention clinical trials demonstrate the efficacy of fibrate therapy in patients with the raised triglycerides-low HDL-C dyslipidemia. This review summarizes current data regarding mechanism of action and the metbolic effects of fibrates, as well as results from major clinical trials on the efficacy of this mode of lipid lowering therapy. In addition, recent data from subgroup analyses of the Bezafibrate Infarction Prevention trial, demonstrating several important metabolic and long-term cardiovascular effects of bezafibrate therapy, are detailed. Keywords: fibrates, high-density lipoprotein-cholsterol, metabolic syndrome, peroxisome proliferator-activated α-receptors, cardiac events
Towards a general model for protein–substrate stereoselectivity (2002)

Protein-substrate interactions in enzymatic, neurological, and immunological systems are typically characterized by a high degree of stereoselectivity towards complex substrates. We propose a novel stereocenter-recognition (SR) model for stereoselectivity of proteins (or receptors in general) towards substrates that have multiple stereocenters, based on the topology of substrate stereocenters. The model provides the minimum number of substrate locations that need to enter into binding, nonbinding, or repulsive interactions with receptor sites, for stereoselectivity to occur. According to this model, a substrate location may interact with multiple receptor sites, or multiple substrate locations may interact with a single receptor site, but a stereoselective receptor has to offer, in the correct geometry, at least as many interactions as the required minimum number of substrate locations. The SR model predicts that stereoselectivity towards an acyclic substrate with N stereocenters distributed along a single chain requires interactions involving a minimum of N + 2 substrate locations, distributed over all stereocenters in the substrate, such that effectively three locations exist per stereocenter. Thus, enantioselective recognition of molecules with one chiral center requires a protein to interact with a minimum of three substrate locations, while stereoselectivity towards substrates with two or three stereocenters requires interactions with a minimum of four or five substrate locations, respectively, and so on. We demonstrate the general applicability of this model to protein-substrate interactions by interpreting several previous experimental observations.
Is Human Immunodeficiency Virus RNA Load Composed of Neutralized Immune Complexes? (2002)

During acute human immunodeficiency virus (HIV) infection, both virus load (HIV RNA) and infectivity are high (10(3)-10(7) RNA copies/mL or TCID(50)/mL) until antibody is produced, which may reduce the HIV infectivity. In HIV carriers, the HIV RNA load is elevated (10(3)-10(5) copies/mL), but infectivity is low (10(0)-10(2) TCID(50)/mL). The low infectivity in carriers could be due to neutralization by antibody in serum, resulting in immune complexes (ICs). We demonstrated that ICs in plasma, prepared with protein A beads, contained HIV RNA (80%-100%) in association with immunoglobulin G (IgG). In comparison, ICs from patients with acute HIV infection and little or no antibody contained virtually no HIV RNA. Moreover, ICs prepared by ultrafiltration contained IgG and specifically and irreversibly neutralized HIV, which indicates that the ICs contained neutralizing antibody. These findings indicate that the HIV RNA in the plasma of carriers is frequently composed of antibody-neutralized HIV as ICs.
Spectrophotometric applications of digital signal processing (2006)

Spectrophotometry is more and more often the method of choice not only in analysis of (bio)chemical substances, but also in the identification of physical properties of various objects and their classification. The applications of spectrophotometry include such diversified tasks as monitoring of optical telecommunications links, assessment of eating quality of food, forensic classification of papers, biometric identification of individuals, detection of insect infestation of seeds and classification of textiles. In all those applications, large numbers of data, generated by spectrophotometers, are processed by various digital means in order to extract measurement information. The main objective of this paper is to review the state-of-the-art methodology for digital signal processing (DSP) when applied to data provided by spectrophotometric transducers and spectrophotometers. First, a general methodology of DSP applications in spectrophotometry, based on DSP-oriented models of spectrophotometric data, is outlined. Then, the most important classes of DSP methods for processing spectrophotometric data—the methods for DSP-aided calibration of spectrophotometric instrumentation, the methods for the estimation of spectra on the basis of spectrophotometric data, the methods for the estimation of spectrum-related measurands on the basis of spectrophotometric data—are presented. Finally, the methods for preprocessing and postprocessing of spectrophotometric data are overviewed. Throughout the review, the applications of DSP are illustrated with numerous examples related to broadly understood spectrophotometry.
Magnetic field enriched surface enhanced resonance Raman spectroscopy for early malaria diagnosis (2012)

Hemozoin is a by-product of malaria infection in erythrocytes, which has been explored as a biomarker for early malaria diagnosis. We report magnetic field-enriched surface-enhanced resonance Raman spectroscopy (SERRS) of β-hematin crystals, which are the equivalent of hemozoin biocrystals in spectroscopic features, by using magnetic nanoparticles with iron oxide core and silver shell (Fe(3)O(4)@Ag). The external magnetic field enriches β-hematin crystals and enhances the binding between β-hematin crystals and magnetic nanoparticles, which provides further improvement in SERRS signals. The magnetic field-enriched SERRS signal of β-hematin crystals shows approximately five orders of magnitude enhancement in the resonance Raman signal, in comparison to about three orders of magnitude improvement in the SERRS signal without the influence of magnetic field. The improvement has led to a β-hematin detection limit at a concentration of 5 nM (roughly equivalent to 30 parasites/μl at the early stages of malaria infection), which demonstrates the potential of magnetic field-enriched SERRS technique in early malaria diagnosis.
Starfire - a commercial tokamak fusion power reactor concept (1980)

The purpose of the STARFIRE study is to develop a design concept for a commercial tokamak fusion electric power plant based on the deuterium/tritium/lithium-fuel cycle. The key technical objective is to develop an attractive embodiment of the tokamak as a power reactor consistent with credible engineering solutions to design problems. 1 ref.
Constraint Integer Programming (2007)

Diese Arbeit stellt einen integrierten Ansatz aus "Constraint Programming" (CP) und Gemischt-Ganzzahliger Programmierung ("Mixed Integer Programming", MIP) vor, den wir "Constraint Integer Programming" (CIP) nennen. Sowohl Modellierungs- als auch Lösungstechniken beider Felder fließen in den neuen integrierten Ansatz ein, um die unterschiedlichen Stärken der beiden Gebiete zu kombinieren. Als weiteren Beitrag stellen wir der wissenschaftlichen Gemeinschaft die Software SCIP zur Verfügung, die ein Framework für Constraint Integer Programming darstellt und zusätzlich Techniken des SAT-Lösens beinhaltet. SCIP ist im Source Code für akademische und nicht-kommerzielle Zwecke frei erhältlich. Unser Ansatz des Constraint Integer Programming ist eine Verallgemeinerung von MIP, die zusätzlich die Verwendung beliebiger Constraints erlaubt, solange sich diese durch lineare Bedingungen ausdrücken lassen falls alle ganzzahligen Variablen auf feste Werte eingestellt sind. Die Constraints werden von einer beliebigen Kombination aus CP- und MIP-Techniken behandelt. Dies beinhaltet insbesondere die "Domain Propagation", die Relaxierung der Constraints durch lineare Ungleichungen, sowie die Verstärkung der Relaxierung durch dynamisch generierte Schnittebenen. Die derzeitige Version von SCIP enthält alle Komponenten, die für das effiziente Lösen von Gemischt-Ganzzahligen Programmen benötigt werden. Die vorliegende Arbeit liefert eine ausführliche Beschreibung dieser Komponenten und bewertet verschiedene Varianten in Hinblick auf ihren Einfluß auf das Gesamt-Lösungsverhalten anhand von aufwendigen praktischen Experimenten. Dabei wird besonders auf die algorithmischen Aspekte eingegangen. Ein weiterer Hauptteil der Arbeit befasst sich mit der Chip-Design-Verifikation, die ein wichtiges Thema innerhalb des Fachgebiets der "Electronic Design Automation" darstellt. Chip-Hersteller müssen sicherstellen, dass der logische Entwurf einer Schaltung der gegebenen Spezifikation entspricht. Andernfalls würde der Chip fehlerhaftes Verhalten aufweisen, dass zu Fehlfunktionen innerhalb des Gerätes führen kann, in dem der Chip verwendet wird. Ein wichtiges Teilproblem in diesem Feld ist das Eigenschafts-Verifikations-Problem, bei dem geprüft wird, ob der gegebene Schaltkreisentwurf eine gewünschte Eigenschaft aufweist. Wir zeigen, wie dieses Problem als Constraint Integer Program modelliert werden kann und geben eine Reihe von problemspezifischen Algorithmen an, die die Struktur der einzelnen Constraints und der Gesamtschaltung ausnutzen. Testrechnungen auf Industrie-Beispielen vergleichen unseren Ansatz mit den bisher verwendeten SAT-Techniken und belegen den Erfolg unserer Methode.
Pro-survival Function of Akt/Protein Kinase B in Prostate Cancer Cells (2001)

Tumor necrosis factor superfamily member TRAIL/Apo-2L has recently been shown to induce apoptosis in transformed and cancer cells. Some prostate cancer cells express constitutively active Akt/protein kinase B due to a complete loss of lipid phosphatase PTEN gene, a negative regulator of phosphatidylinositol 3-kinase pathway. Constitutively active Akt promotes cellular survival and resistance to chemotherapy and radiation. We have recently noticed that some human prostate cancer cells are resistant to TRAIL. We therefore examined the intracellular mechanisms of cellular resistance to TRAIL. The cell lines expressing the highest level of constitutively active Akt were more resistant to undergo apoptosis by TRAIL than those expressing the lowest level. Down-regulation of constitutively active Akt by phosphatidylinositol 3-kinase inhibitors, wortmannin and LY294002, reversed cellular resistance to TRAIL. Treatment of resistant cells with cycloheximide (a protein synthesis inhibitor) rendered cells sensitive to TRAIL. Transfecting dominant negative Akt decreased Akt activity and increased TRAIL-induced apoptosis in cells with high Akt activity. Conversely, transfecting constitutively active Akt into cells with low Akt activity increased Akt activity and attenuated TRAIL-induced apoptosis. Inhibition of TRAIL sensitivity occurs at the level of BID cleavage, as caspase-8 activity was not affected. Enforced expression of anti-apoptotic protein Bcl-2 or Bcl-X(L) inhibited TRAIL-induced mitochondrial dysfunction and apoptosis. We therefore identify Akt as a constitutively active kinase that promotes survival of prostate cancer cells and demonstrate that modulation of Akt activity, by pharmacological or genetic approaches, alters the cellular responsiveness to TRAIL. Thus, TRAIL in combination with agents that down-regulate Akt activity can be used to treat prostate cancer.
A Report on the Use of the Bekesy Audiometer in the Performance of the Stenger Test (1964)

No AccessJournal of Speech and Hearing DisordersResearch Article1 Feb 1964A Report on the Use of the Békésy Audiometer in the Performance of the Stenger Test John E. Watson, and Richard J. Voots John E. Watson Google Scholar More articles by this author and Richard J. Voots Google Scholar More articles by this author https://doi.org/10.1044/jshd.2901.36 SectionsAboutPDF ToolsAdd to favoritesDownload CitationTrack Citations ShareFacebookTwitterLinked In Additional Resources FiguresReferencesRelatedDetailsCited by E. Harris Nober (1981) Pseudohypacusic Disturbance in Adults Communication Disorders10.1007/978-1-4757-9760-2_10 Volume 29Issue 1February 1964Pages: 36-46 Get Permissions Add to your Mendeley library History Published in issue: Feb 1, 1964PubMed ID: 14122666 Metrics Topicsasha-topicsasha-article-typesleader-topicsCopyright & PermissionsCopyright © 1964 American Speech-Language-Hearing AssociationPDF downloadLoading ...
Study of Wetting in an Asymmetrical Vane-Wall Gap in Propellant Tanks (2006)

Wetting of an asymmetrical vane-wall gap geometry is investigated. The geometry is common in vane-type liquid propellant management devices. Critical wetting conditions are determined by applying the method by Concus and Finn (Concus, P., and Finn, R., On Capillary Free Surfaces in the Absence of Gravity, Acta Mathematica, Vol. 132, 1974, pp. 177-198). The critical wetting condition is expressed in terms of critical contact angle as a function of gap size, with the vane thickness and obliquity angle as relevant parameters. It is found that the increase of both the vane thickness and the obliquity angle improves the critical wetting conditions. The analytical results are confirmed with Surface Evolver numerical computations, which also provide graphical descriptions of capillary surfaces. Results from drop tower experiments confirm the analysis and also reveal that the advance rate of the meniscus tip decreases with the gap size when other parameters are fixed.
PLASTIC SPONGE WHICH ACTS AS A FRAMEWORK FOR LIVING TISSUE (1951)

SURGEONS have learned that certain nonabsorbable foreign materials are occasionally useful in surgical reconstruction of certain organs and structures of the body. They have learned that although the foreign material is inferior to living tissue in many respects and never becomes truly a part of the body, materials such as tantalum, vitallium, stainless steel, polyethylene, polyvinyl and methyl methacrylate will often serve in place of living tissue to fill defects or correct deformities. The limitations of foreign materials used at present are well recognized. Foremost of these limitations, and common to all materials in widespread use, is failure to become united with surrounding living tissue. In certain circumstances this characteristic is not a limitation but a desirable quality, in others it is more or less of a handicap, and in still others it constitutes an objection to the use of foreign material. Hence, the finding of nonabsorbable materials, which not
High Accuracy Evaluation of the Finite Fourier Transform Using Sampled Data (1997)

Many system identification and signal processing procedures can be done advantageously in the frequency domain. A required preliminary step for this approach is the transformation of sampled time domain data into the frequency domain. The analytical tool used for this transformation is the finite Fourier transform. Inaccuracy in the transformation can degrade system identification and signal processing results. This work presents a method for evaluating the finite Fourier transform using cubic interpolation of sampled time domain data for high accuracy, and the chirp z-transform for arbitrary frequency resolution. The accuracy of the technique is demonstrated in example cases where the transformation can be evaluated analytically. Arbitrary frequency resolution is shown to be important for capturing details of the data in the frequency domain. The technique is demonstrated using flight test data from a longitudinal maneuver of the F-18 High Alpha Research Vehicle.
Electronically tunable bandpass filter (1990)

An electronically tunable bandpass filter is presented. It is a combline filter realized in microstrip form. The filter is made tunable by using the variable capacitance of a GaAs fet (or of a varactor). With the use of this technique it is possible to achieve relative bandwidth from 8% to 30%, a tuning bandwidth 'up to 50% and a center frequency up to 18 GHz. A remarkable characteristic of this device is that it requires no driving current and it presents only a capacitive load (of about 10 pF) to its driver. So, we have an electronically tunable fil­ter with a tuning time of a few nanoseconds. This paper describes method of de­sign, simulation and performance of some monolitic realizations of the filter.
Flexural beam-based fiber Bragg grating accelerometers (1998)

A flexural beam is utilized as the primary transduction mechanism for demonstrating a series of fiber Bragg grating (FBG) accelerometers. The fully packaged FBG accelerometers reported in this work have many desirable features including good acceleration sensitivity (212.5 μ/spl epsiv//g), high resonant frequencies (on the order of 1 kHz), very low cross-axis sensitivity (<1% of the primary axial responsivity), and low noise (/spl sim/1 mg//spl radic/(Hz) near 1 Hz). Arrays of such devices can be utilized in a variety of applications, including structural monitoring. Closed-form analytical formulas describing the resonant frequency and responsivity of the FBG accelerometer are provided which may be utilized to tailor the sensor performance to specific applications.
A Modification to the Monte Carlo Method—The Exodus Method (1968)

A modification to the Monte Carlo method is described which reduces calculation time and improves the accuracy. This method—termed “Exodus”—is not dependent upon a random number generator and may be applied to any problem which admits of a nodal network.