gebhart/patrepeval huggingface dataset:
Reduced transcription of the ferredoxin gene in metronidazole-resistant Trichomonas vaginalis. (1992)

Metronidazole [1-(2-hydroxyethyl)-2-methyl-5-nitroimidazole] is used to treat infections caused by Trichomonas vaginalis, a sexually transmitted human parasite. This drug is administered in an inactive form and is reduced to its cytotoxic form within the hydrogenosome, an unusual organelle found in trichomonads. Metronidazole reduction occurs via ferredoxin-mediated electron transport. We have investigated the role of ferredoxin in metronidazole resistance. Immunoblot analysis of drug-resistant and -sensitive T. vaginalis strains shows that intracellular levels of ferredoxin are invariably reduced in the resistant strains relative to a sensitive strain. Similarly, Northern blot analysis shows that ferredoxin mRNA levels are reduced 50-65% in resistant strains. Using nuclear run-on assays, we show that ferredoxin gene transcription is reduced 40-65% in resistant strains. Sequence comparison of the region 5' of the ferredoxin gene among drug-sensitive and -resistant strains reveals two point mutations, at -178 and -239 nucleotides relative to the start of transcription, in a resistant strain. Interestingly, a protein of approximately 23 kDa binds to a 28-base-pair region that encompasses the mutation at -239 nucleotides. The binding affinity of this protein appears to be reduced in the mutant. These data strongly correlate drug resistance with altered regulation of ferredoxin gene transcription. A reduction in gene transcription results in decreased intracellular levels of ferredoxin. This, in turn, may play a role in metronidazole resistance by decreasing the ability of the cell to activate the drug.
Syntheses of Biodegradable and Biocompatible Polymers by Means of Bismuth Catalysts (2009)

ADVERTISEMENT RETURN TO ISSUEPREVReviewNEXTSyntheses of Biodegradable and Biocompatible Polymers by Means of Bismuth CatalystsHans R. KricheldorfView Author Information Institut für Technische und Makromolekulare Chemie, Bundesstrasse 45, D-20146 Hamburg, GermanyCite this: Chem. Rev. 2009, 109, 11, 5579–5594Publication Date (Web):September 24, 2009Publication History Received23 January 2009Published online24 September 2009Published inissue 11 November 2009https://pubs.acs.org/doi/10.1021/cr900029ehttps://doi.org/10.1021/cr900029ereview-articleACS PublicationsCopyright © 2009 American Chemical SocietyRequest reuse permissionsArticle Views4620Altmetric-Citations97LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Bismuth,Catalysts,Copolymers,Organic polymers,Polymerization Get e-Alerts
Direito, Estado e Telecomunicações: a força gravitacional da banda larga (2011)

O presente estudo figura como introdução à Revista de Direito, Estado e Telecomunicações do Grupo de Estudos em Direito das Telecomunicações da Universidade de Brasília, abordando sinteticamente a estrutura, conteúdo e política editorial da revista. Em acréscimo, o texto analisa os principais acontecimentos do setor no Brasil, bem como normas e julgados relativos ao ano de 2010, para registro das principais discussões jurídico-políticas do setor de telecomunicações brasileiro referentes ao ano anterior ao da publicação.
Iterative approach for the numerical simulation of scattering from one- and two-dimensional rough surfaces (1993)

We describe the use of iterative techniques for the solution of the integral equation that arises in an exact treatment of scalar wave scattering from randomly rough surfaces. The surfaces vary in either one or two dimensions, and the special case of a Dirichlet boundary condition is treated. It is found that these techniques, particularly when preconditioning is applied, are much more efficient than direct inversion techniques. Moreover, convergence is obtained for rms roughness of the order of 1, so the techniques have applicability over a wide parameter regime. Convergence is always to the exact solution found by direct inversion, exceptly for cases of extremely large-scaled rms surface heights in which the iterative techniques fail. In addition, by monitoring the residuals in the iteration process, it is immediately clear if the iterative techniques are failing, or performing badly in any given case. Finally, numerical results are compared with existing data in the enhanced backscattering regime.
Studies of two-dimensional liquid-wedge impact and their relevance to liquid-drop impact problems (1985)

Abstract In the initial stage of liquid-drop impact, the contact region expands faster than the wave speed in the liquid. This causes compressible behaviour in the liquid, and high transient pressures. High-velocity jetting results when the wave motion in the liquid overtakes the expanding contact edge and moves up the free surface of the drop. The detailed pressure fields in this early time history of impact have been calculated by Lesser (Proc. R. Soc. Lond. 377, 289 (1981)) for both two and three-dimensional liquid masses and for targets of finite admittance. An important result is that the edge pressures exceed the central ‘water-hammer’ pressure 3ρ0CUi and at the time of shock-detachment approach ca. 3ρ0CUi. At this stage the edge pressures, for both spherical drops and two-dimensional liquid wedges, depend only on the impact velocity and the instantaneous angle between the liquid and solid surfaces. This suggests that the essential features of the early stage of liquid impact can be usefully studied by producing impacts with two-dimensional liquid wedges, and predicted data for pressures, shock angles and velocities are presented. Experiments are described for producing impacts with preformed shapes by using water-gelatine mixtures and observing the impact events with high-speed photography. The results confirm the main features of the model and give information on edge pressures, jetting, cavitation in the liquid and the effect of the admittance of the solid. The relevance of the results to the damage and erosion of materials subjected to liquid impact is discussed. In particular, it is possible to explain the apparently low damage-threshold of some materials, the form of damage and its development with repeated impact. The study highlights the importance of the detailed surface geometry in the region of contact.
Mechanism for the prevention of cholestasis involving cytochrome P4503A overexpression. (2000)

Bile acid structure seems to be linked with hepatotoxicity/hepatoprotection and P4503A modulation. Taurohyodeoxycholic acid could be therapeutic in cholestatic liver disease by inducing P4503A; we can hypothesize that an associated P-glycoprotein expression might facilitate biliary excretion of toxic taurochenodeoxycholic acid accumulated in the liver during cholestasis.
Fast spectroscopic imaging using online optimal sparse<i>k</i>‐space acquisition and projections onto convex sets reconstruction (2006)

Long acquisition times, low resolution, and voxel contamination are major difficulties in the application of magnetic resonance spectroscopic imaging (MRSI). To overcome these difficulties, an online-optimized acquisition of k-space, termed sequential forward array selection (SFAS), was developed to reduce acquisition time without sacrificing spatial resolution. A 2D proton MRSI region of interest (ROI) was defined from a scout image and used to create a region of support (ROS) image. The ROS was then used to optimize and obtain a subset of k-space (i.e., a subset of nonuniform phase encodings) and hence reduce the acquisition time for MRSI. Reconstruction and processing software was developed in-house to process and reconstruct MRSI using the projections onto convex sets method. Phantom and in vivo studies showed that good-quality MRS images are obtainable with an approximately 80% reduction of data acquisition time. The reduction of the acquisition time depends on the area ratio of ROS to FOV (i.e., the smaller the ratio, the greater the time reduction). It is also possible to obtain higher-resolution MRS images within a reasonable time using this approach. MRSI with a resolution of 64 x 64 is possible with the acquisition time of the same as 24 x 24 using the traditional full k-space method.
Vibration Prediction for Rotor System with Faults Using Coupled Rotor-Fuselage Model (2004)

A coupled rotor-fuselage vibration analysis is formulated to analyze the effect of rotor system faults on fuselage vibrations and rotor-blade displacements in both hover and forward-flight conditions. Two groups of rotor-system faults, adjustable and nonadjustable component faults, are modeled. Results are presented for an SH-60 helicopter and are compared with available flight-test data. A detailed aeroelastic analysis is carried out where each rotor blade is modeled individually such that rotor dissimilarity can be considered. A fuselage NASTRAN model is incorporated and coupled with the rotor model analysis. The centrifugally tuned, hub-mounted bifilar vibration absorbers are also modeled, and the coupled rotor-fuselage-bifilar nonlinear equations are solved using finite element method in space and time
Induction of Apoptosis and Subsequent Phagocytosis of Virus-Infected Cells As an Antiviral Mechanism (2017)

Viruses are infectious entities that hijack host replication machineries to produce their progeny, resulting, in most cases, in disease and, sometimes, in death in infected host organisms. Hosts are equipped with an array of defense mechanisms that span from innate to adaptive as well as from humoral to cellular immune responses. We previously demonstrated that mouse cells underwent apoptosis in response to influenza virus infection. These apoptotic, virus-infected cells were then targeted for engulfment by macrophages and neutrophils. We more recently reported similar findings in the fruit fly Drosophila melanogaster, which lacks adaptive immunity, after an infection with Drosophila C virus. In these experiments, the inhibition of phagocytosis led to severe influenza pathologies in mice and early death in Drosophila. Therefore, the induction of apoptosis and subsequent phagocytosis of virus-infected cells appear to be an antiviral innate immune mechanism that is conserved among multicellular organisms. We herein discuss the underlying mechanisms and significance of the apoptosis-dependent phagocytosis of virus-infected cells. Investigations on the molecular and cellular features responsible for this underrepresented virus-host interaction may provide a promising avenue for the discovery of novel substances that are targeted in medical treatments against virus-induced intractable diseases.
Mechanistic models for additive manufacturing of metallic components (2020)

Additive manufacturing (AM), also known as 3D printing, is gaining wide acceptance in diverse industries for the manufacturing of metallic components. The microstructure and properties of the components vary widely depending on printing process and process parameters, and prediction of causative variables that affect structure, properties and defects is helpful for their control. Since models are most useful when they can correctly predict experimental observations, we focus on the available mechanistic models of AM that have been adequately validated. Specifically, the applications of transport phenomena models in the studies of solidification, residual stresses, distortion, formation of defects and the evolution of microstructure and properties are critically reviewed. The functionality of AM models in understanding of the printability of commonly used AM alloys and the fabrication of functionally graded alloys are also assessed. Opportunities for future research are identified considering the gaps in knowledge in modeling. The uniqueness of this review includes substantive discussions of the rapid certification of the AM components aided by scale models, bidirectional models, cloud based big data, machine learning and digital twins of AM hardware.
Automatic heap sizing (2004)

Heap size has a huge impact on the performance of garbage collected applications. A heap that barely meets the application's needs causes excessive GC overhead, while a heap that exceeds physical memory induces paging. Choosing the best heap size <i>a priori</i> is impossible in multiprogrammed environments, where physical memory allocations to processes change constantly. We present an automatic heap-sizing algorithm applicable to different garbage collectors with only modest changes. It relies on an analytical model and on detailed information from the virtual memory manager. The model characterizes the relation between collection algorithm, heap size, and footprint. The virtual memory manager tracks recent reference behavior, reporting the current footprint and allocation to the collector. The collector uses those values as inputs to its model to compute a heap size that maximizes throughput while minimizing paging. We show that our adaptive heap sizing algorithm can substantially reduce running time over fixed-sized heaps.
Regulation of the UNC-18–<i>Caenorhabditis elegans</i>Syntaxin Complex by UNC-13 (1999)

The Caenorhabditis elegans unc-13, unc-18, and unc-64 genes are required for normal synaptic transmission. The UNC-18 protein binds to the unc-64 gene product C. elegans syntaxin (Ce syntaxin). However, it is not clear how this protein complex is regulated. We show that UNC-13 transiently interacts with the UNC-18-Ce syntaxin complex, resulting in rapid displacement of UNC-18 from the complex. Genetic and biochemical evidence is presented that UNC-13 contributes to the modulation of the interaction between UNC-18 and Ce syntaxin.
Keys to a Positive First Impression (1998)

The author identifies the common mistakes that practices make in patient relations and offers practical tips on how to make a good first impression with patients.
Combustion efficiency optimization manual for operators of oil- and gas-fired boilers. Final report (1983)

This manual provides general guidance to operators of oil- and gas-fired boilers to increase boiler efficiency, improve fuel consumption, and to reduce pollutant emissions. Boiler operating principles and suggestions to improve boiler performance are discussed. Combustion is explained in simple terms. Various heat losses are described, and suggestions are given on means to minimize or eliminate heat losses. The manual describes boiler adjustments for peak operating efficiency, optimum fuel consumption, and reduced pollutant emissions. Efficiency, fuel consumption, and emissions are all sensitive to many of the same boiler operating parameters. This manual describes feasible operating techniques and combustion adjustments to achieve clean, safe, and efficient boiler operation.
Co-catalysed VLS growth of novel ceramic nanostructuresElectronic supplementary information (ESI) available: TEM, SEM and HRTEM images for MgO, SiOx and AlOx ceramic nanomaterials. See http://www.rsc.org/suppdata/jm/b3/b312498n/ (2004)

Metal particle-catalysed generation of a series of novel nanostructures, via the well-known VLS step first described as a micrometer-scale fibre growth mechanism, is discussed. The resulting nanomaterials were characterised using HRTEM, SEM, EDX and XRD, and the results showed that these materials could be valuable components in constructing nano- and micro-machines.
Optimum population size and mutation rate for a simple real genetic algorithm that optimizes array factors (2002)

There has been an explosion of papers describing applications of a genetic algorithm (GA) to electromagnetics problems. Most of the work has followed traditional GA philosophy when choosing the population size and mutation rate of the genetic algorithm. This paper reports the results of experiments to determine the optimum population size and mutation rate for a simple real genetic algorithm. The choice of population size and mutation rate can cause the run time of the GA to vary by several orders of magnitude. The results of this investigation show that a small population size and relatively large mutation rate is far superior to the large population sizes and low mutation rates that is used by most of the papers presented in the electromagnetics community and by the GA community at large. The results of the numerical experiments presented in this paper suggest that the best mutation rate for GAs lies between 5 and 20% while the population size should be less than 16.
Cloning of Rat and Human Inducible Penile Nitric Oxide Synthase. Application for Gene Therapy of Erectile Dysfunction1 (1997)

Erectile dysfunction is mainly due to the inability of the cavernosal smooth muscle of the penis to undergo complete relaxation. In the aging rat model, erectile dysfunction is accompanied by a reduction of penile smooth muscle compliance and, in very old animals, by a decrease in penile nitric oxide synthase (NOS), which is responsible for the synthesis of the mediator of penile erection, nitric oxide (NO). We have investigated whether the stimulation of penile NOS expression by local induction or gene therapy can mitigate erectile dysfunction in the aged rat. A mix of iNOS (inducible NOS) inducers was continuously delivered to the penises of 5- ("adult"), 20- ("old"), and 30- ("very old") mo-old rats for 3-6 days, and the erectile response to electrical field stimulation of the cavernosal nerve was measured. The erectile dysfunction observed in old and very old rats as compared to adult animals was ameliorated by treatment with iNOS inducers. Penile iNOS was detectable in the penis of these rats by Western blot, NADPH diaphorase, and NOS activity assays. Inducible NOS was inducible in vitro in both rat and human corpora cavernosal tissue and in rat penile smooth muscle cells (RPSMC), as shown by Western blots. However, NO synthesis in cavernosal tissue upon iNOS protein induction remained low, indicating that the increased NOS levels were under physiological control. The iNOS cDNA was cloned from induced RPSMC mRNA and generated by reverse transcriptase polymerase chain reaction (RT-PCR) from induced human penile smooth muscle cells and corporal tissue. The coding regions from both the rat (RPiNOS) and human (HPiNOS) penile iNOS showed several amino acid differences from their analogous isoform in nonpenile tissues. RPiNOS cDNA injected into the penis mitigated the aging-associated erectile dysfunction. The iNOS construct was detected in cavernosal tissue by PCR, and its expression by RT-PCR and Western blots. These results open the way for the possible use of NOS isoforms in the management of erectile dysfunction.
NMR relaxation and structural elucidation of peptides in the presence and absence of trifluoroethanol illuminates the critical molecular nature of integrin αvβ6 ligand specificity (2012)

Integrin αvβ6 is an important emerging target for both imaging and therapy of cancer that requires specific ligands based on Arg-Gly-Asp (RGD) peptides. There remains little correlation between integrin-RGD ligand specificity despite studies suggesting an RGD-turn-helix ligand motif is required. Here, we describe the application of <sup>15</sup>N NMR relaxation analyses and structure determination of αvβ6 peptide ligands in the presence and absence of trifluoroethanol (TFE) to identify their critical molecular nature that influences specificity, interaction and function. Two linear peptides; one known to demonstrate αvβ6 specificity (FMDV2) and the other based on a natural RGD ligand (LAP2), were compared to two additional peptides based on FMDV2 but cyclised in different positions using a disulphide bond (DBD1 and DBD2). The cyclic adaptation in DBD1 produces a significant alteration in backbone dynamic properties when compared to FMDV2; a potential driver for the loss in αvβ6 specificity by DBD1. The importance of ligand dynamics are highlighted through a comprehensive reduced spectral density and ModelFree analysis of peptide <sup>15</sup>N NMR relaxation data and suggest αvβ6 specificity requires the formation of a structurally rigid helix preceded by a RGD motif exhibiting slow internal motion. Additional observations include the effect of TFE/water viscosity on global NMR dynamics and the advantages of using spectral density NMR relaxation data to estimate correlation times and motional time regimes for peptides in solution.
Synthesis of Trifluoromethyl-allenes by Gold-Catalyzed Rearrangement of Propargyl Benzyl Ethers (2016)

A new method for the synthesis of trifluoromethyl-allenes from easily accessible α-trifluoromethyl-propargyl benzyl ether derivatives following a gold-catalyzed intramolecular hydride transfer has been developed. Various di- and trisubstituted trifluoromethyl-allenes were obtained in good to excellent yields.
Work function of WSi<sub>2</sub> (1980)

The work function of tungsten disilicide (WSi <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> ) has been measured by MOS capacitance-voltage technique. MOS capacitors with WSi <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> as the gate material have been fabricated on n-type
First Determination of the Inhibitor Complex Structure of Human Hematopoietic Prostaglandin D Synthase (2004)

Hematopoietic prostaglandin (PG) D synthase (H-PGDS) is responsible for the production of PGD(2) as an allergy or inflammation mediator in mast and Th2 cells. We determined the X-ray structure of human H-PGDS complexed with an inhibitor, 2-(2'-benzothiazolyl)-5-styryl-3-(4'-phthalhydrazidyl) tetrazolium chloride (BSPT) at 1.9 A resolution in the presence of Mg(2+). The styryl group of the inhibitor penetrated to the bottom of the active site cleft, and the tetrazole ring was stabilized by the stacking interaction with Trp104, inducing large movement around the alpha5-helix, which caused the space group of the complex crystal to change from P2(1) to P1 upon binding of BSPT. The phthalhydrazidyl group of BSPT exhibited steric hindrance due to the cofactor, glutathione (GSH), increasing the IC(50) value of BSPT for human H-PGDS from 36.2 micro M to 98.1 micro M upon binding of Mg(2+), because the K(m) value of GSH for human H-PGDS was decreased from 0.60 micro M in the presence of EDTA to 0.14 micro M in the presence of Mg(2+). We have to avoid steric hindrance of the GSH molecule that was stabilized by intracellular Mg(2+) in the mM range in the cytosol for further development of structure-based anti-allergic drugs.
Writers' Exchange (2014)

In this epistolary exchange between eminent Chinese literary critics Zhang Ning and Sun Yu, they follow up on a disagreement voiced in an earlier symposium regarding writer and painter Mu Xin, a member of the Chinese diaspora. Sun Yu argues that Mu Xin's work deserves to be read more widely in mainland China, citing his important contributions to Chinese literary form and rhetoric. Zhang Ning, however, does not back down from his earlier resistance to what he argues amounts to overpraise for Mu Xin's work, citing it as an interesting and worthy example of literary memoir but not as the best representation of literary history.