gebhart/patrepeval huggingface dataset:
Polyphosphate Kinase Protects <i>Salmonella enterica</i> from Weak Organic Acid Stress (2005)

Mutants of Salmonella enterica lacking polyphosphate kinase (ppk) grow poorly in the presence of the weak organic acids acetate, propionate, and benzoate. This sensitivity is corrected by methionine and seems to result from destabilization of MetA (homoserine transsuccinylase), the first enzyme in methionine biosynthesis. The MetA protein is known to be sensitive to thermal inactivation, and ppk mutants are more sensitive to heat-induced methionine auxotrophy. Peroxide increases the sensitivity of ppk mutants to both heat and acid and may oxidatively damage (carbonylate) destabilized MetA. While acid appears to impair methionine biosynthesis, it leads to derepression of MetA and may inhibit growth by causing toxic accumulation of denatured protein. This is supported by the observation that the overexpression of MetA in ppk mutants causes acid sensitivity that is not corrected by methionine. We propose that polyphosphate acts as a chemical chaperone that helps refold MetA and/or may stimulate proteolysis of toxic denatured protein. The instability of MetA protein may provide a metabolic fuse that blocks growth under conditions that denature proteins; the sensitivity of this fuse is modulated by polyphosphate.
The Molecular Basis of Triazine-Herbicide Resistance in Higher-Plant Chloroplasts (1984)

Triazine herbicides inhibit photosynthesis by blocking electron transport in photosystem II. The target site of the herbicide was identified as a chloroplast thylakoid polypeptide (the Q в protein) of 32,000 daltons. Studies of triazine-resistant weed biotypes suggested that a subtle change in the Q в protein caused the resistance. We have cloned the chloroplast gene (psbA) that codes this protein from herbicide-resistant and herbicide-susceptible biotypes of Solanum nigrum. By DNA sequencing we detected a single base substitution in the psbA gene of the resistant plants, resulting in an amino acid change (serine to glycine for the susceptible to resistance conversion). This mutation is exactly the same one which we have described in a herbicide-resistant biotype of Amaranthus hybridus.
Elemental Sulfur in Bituminous Coals (1990)

Many coals contain elemental sulfur. It is clearly a ubiquitous constituent of bituminous coals that have been exposed to the atmosphere. In contrast, three pristine samples obtained from the Premium Sample Program at the Argonne National Laboratory are free of elemental sulfur within the detection limit of four sensitive analytical methods. Exposure of the pristine coals to the atmosphere leads to the production of elemental sulfur. These observations strongly suggest that sulfur is not a natural constituent of coal, but rather is produced after exposure to the atmosphere by Chemical or bacteriological action.
Application of a PLC as a cell controller using a communication network (1995)

Design and implementation of a low cost flexible production unit for assembly, inspection and other sequential tasks while maintaining an open system architecture is explained. All components of the cell are connected to the production unit controller, a PLC, via the installation bus controller area network (CAN). The design is flexible to accept a number of sensors with different functionality such as pressure, temperature, bar-code readers etc. which may be connected to the bus individually or via an intelligent peripheral device.
Analysis of the <i>rnc</i> locus of <i>Coxiella burnetii</i> (1994)

A 3.2 kb EcoRI genomic DNA fragment of Coxiella burnetii was isolated by virtue of its ability to suppress mucoidy in Escherichia coli. Nucleotide sequence analysis revealed the presence of the genes homologous to rnc, era and recO of E. coli. Suppression of capsule synthesis, measured by beta-galactosidase expression in lon- cps-lac fusion strains of E. coli, is caused by gene-dosage effects of the plasmid-borne rnc genes of either C. burnetii or E. coli. The rnc gene of C. burnetii complemented rnc- E. coli hosts for lambda plaque morphology and stimulation of lambda N gene expression. We also demonstrated heterologous complementation of an E. coli strain defective for the expression of Era, an essential protein in E. coli, using the plasmid-borne C. burnetii era. Under the control of the bacteriophage lambda PL promoter, this 3.2 kb EcoRI DNA fragment directed the synthesis in E. coli of three proteins with approximate molecular masses of 35, 27 and 25 kDa. Antibodies against purified E. coli Era protein cross-reacted with the 35 kDa protein of C. burnetii on Western blots.
Evidence-based dentistry and esthetics. (2001)

Separating hype from the truth in dental marketing can be frustrating and it is difficult at best for the average dentist to evaluate the safety and efficacy of new products and techniques. Keynote clinicians are presenting information and influencing other dentists without the scientific evidence to support their claims. For the benefit of our patients, the system needs to change. It will not come soon, but until more evidence-based testing is commonplace and made readily available to the practicing dentist, most dentists will continue tradition-based practices.
Dielectric changes in membrane properties and cell interiors of human mesothelial cells in vitro after crocidolite asbestos exposure. (2000)

Asbestos induces cytogenetic and genotoxic effects in cultured cell lines in vitro. For further investigations of the fiber-induced cellular changes, electrorotation (ROT) measurements can be used to determine early changes of surface properties and dielectric cellular changes. In the present study, human mesothelial cells (HMC) were exposed to nontoxic concentrations of crocidolite asbestos (1 microg/cm(2)) for 12, 24, 30, 50, and 72 hr, and were investigated for changes in dielectric properties, morphologic and biochemical changes using ROT measurements, electron microscopy, and flow cytometry, respectively. The results of ROT measurements revealed slightly increased internal conductivity and decreased membrane conductance of HMC during the first 12 hr of exposure to crocidolite. This may be due to functional changes of ion channels of the cellular membrane. However, after exposures of >= 30 hr, reduced internal conductivity and increased membrane conductance of HMC occurred. These effects may be caused by permeabilization of the cell membrane and the leakage of ions into the surrounding medium. The membrane capacitance of HMC is always decreased during exposure of cells to crocidolite fibers. This decreased membrane capacitance may result from the observed reduction in the number of microvilli and from the shrinkage of cells as observed by electron microscopy and flow cytometry. Changes in composition of the plasma membrane were also observed after the labeling of phosphatidylserines (PS) on the cell surface. These observed changes can be related to apoptotic events. Whereas during the first 50 hr of exposure only a small number of HMC with increased exposure of PS on the cell surface was detected by flow cytometry, the dielectric properties of HMC showed marked changes during this time. Our results show that surface property changes of the cellular membrane of HMC as well as interior dielectric changes occur after the exposure of cells to crocidolite fibers. The observed changes are discussed in terms of complex combined cellular effects after amphibole asbestos exposure.
Transfer of "Nocardia aerocolonigenes" (Shinobu and Kawato 1960) Pridham 1970 into the Genus Saccharothrix Labeda, Testa, Lechevalier, and Lechevalier 1984 as Saccharothrix aerocolonigenes sp. nov. (1986)

I propose that “Nocardia aerocolonigenes” be placed in the genus Saccharothrix as Saccharothrix aerocolonigenes because it exhibits the following chemotaxonomic properties characteristic of this genus: Whole-cell hydrolysates contain the meso isomer of diaminopimelic acid, rhamnose and galactose are the characteristic sugars, and mycotic acids are absent. This species is phenotypically different from the type species of Saccharothrix, Saccharothrix australiensis (strain NRRL 11239), and deoxyribonucleic acid from the type strain of S. aerocolonigenes was determined to be only 10% homologous to deoxyribonucleic acid isolated from S. australiensis NRRL 11239. A description of the species is presented. The type strain is strain NRRL B-3298 (= ISP 5034 = ATCC 23870 = IFO 3837 = Shinobu No. 701).
Nonlinear distortion generated by dispersive transmission of chirped intensity-modulated signals (1991)

Transmission through dispersive and nonlinear optical fibers produces distortion in subcarrier intensity-modulated systems. Analytic expressions for second- and third-order distortion are derived using the time-domain form of the field envelope wave equation. The distortion predicted by these expressions agrees well with numerical simulation and reasonably well with experimental data. Significant composite second-order distortion is predicted in typical 1.55 mu m cable television systems.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
T cell regulation of B cell activation. An antigen-mediated tripartite interaction of Ts cells, Th cells, and B cells is required for suppression. (1984)

To determine the requirements underlying the antigen specificity observed in T cell-mediated immune response suppression, cloned major histocompatibility complex (MHC)-restricted T suppressor (Ts) cells specific for keyhole limpet hemocyanin (KLH) and cloned MHC-restricted T helper (Th) cells specific for fowl gamma-globulin (FGG) were employed to study the regulation of trinitrophenyl (TNP)-specific B cell responses. Neither antigen bridging between Ts cells and Th cells (FGG=KLH) nor bridging between Ts cells and B cells (TNP-KLH) was sufficient to allow suppression; a mixture of FGG=KLH and TNP-KLH was also insufficient for suppression. In contrast, suppression was induced by KLH-specific Ts cells only when suppressor determinants (KLH), helper determinants (FGG), and B cell determinants (TNP) were covalently linked on the same molecule (TMP-FGG)=(TNP-KLH) or TNP-(FGG=KLH)). These findings imply that a tripartite antigen-mediated interaction of Ts cells, Th cells, and responding B cells is necessary for the mediation of this antigen-specific suppression.
Global analysis of transcript and protein levels across the <i>Plasmodium falciparum</i> life cycle (2004)

To investigate the role of post-transcriptional controls in the regulation of protein expression for the malaria parasite, Plasmodium falciparum, we have compared mRNA transcript and protein abundance levels for seven different stages of the parasite life cycle. A moderately high positive relationship between mRNA and protein abundance was observed for these stages; the most common discrepancy was a delay between mRNA and protein accumulation. Potentially post-transcriptionally regulated genes are identified, and families of functionally related genes were observed to share similar patterns of mRNA and protein accumulation.
High-performance nMOSFET with in-situ phosphorus-doped embedded Si:C (ISPD eSi:C) source-drain stressor (2008)

For the first time, embedded Si:C (eSi:C) was demonstrated to be a superior nMOSFET stressor compared to SMT or tensile liner (TL) stressors. eSi:C nMOSFET showed higher channel mobility and drive current over our best poly-gate 45nm-node nMOSFET with SMT and tensile liner stressors. In addition, eSi:C showed better scalability than SMT plus tensile liner stressors from 380nm to 190nm poly-pitches.
Metal‐Catalyzed α‐Arylation of Carbonyl and Related Molecules: Novel Trends in CC Bond Formation by CH Bond Functionalization (2010)

Alpha-arylated carbonyl compounds are commonly occurring motifs in biologically interesting molecules and are therefore of high interest to the pharmaceutical industry. Conventional procedures for their synthesis often result in complications in scale-up, such as the use of stoichiometric amounts of toxic reagents and harsh reaction conditions. Over the last decade, significant efforts have been directed towards the development of metal-catalyzed alpha-arylations of carbonyl compounds as an alternative synthetic approach that operates under milder conditions. This Review summarizes the developments in this area to date, with a focus on how the substrate scope has been expanded through selection of the most appropriate synthetic method, such as the careful choice of ligands, precatalysts, bases, and reaction conditions.
Regression of sclerodermatous skin lesions in a patient with carcinoid syndrome treated by octreotide (1995)

The principal skin manifestations of carcinoid syndrome are flush, acral pigmentation, cyanosis, and facial telangiectases. We describe herein a patient with carcinoid syndrome whose sclerodermatous lesions of the lower legs, an infrequent manifestation of this syndrome, have entirely subsided with chemotherapy and administration of the long-acting somatostatin analogue octreotide. <h3>Report of a Case.</h3> A 51-year-old white man was admitted in October 1990 for abdominal pain, diarrhea, and weight loss. On clinical examination, a metastatic liver, ascites, edema of the legs, and failure of the right side of the heart were found. The liver biopsy specimen revealed a poorly differentiated metastatic carcinoma whose origin was initially unknown. The first 5-day course of alternate chemotherapy was administered as follows: fluorouracil, 375 mg/m<sup>2</sup>daily; folinic acid, 200 mg/m<sup>2</sup>daily; and cisplatin, 15 mg/m<sup>2</sup>daily, alternated with streptozotocin, 500 mg/m<sup>2</sup>daily. In December 1990, the patient was referred to the
The expression of N-cadherin, fibronectin during chondrogenic differentiation of MSC induced by TGF-beta(1). (2005)

Cell adhesion factors play an important role during cell differentiation. TGF-beta(1) stimulates chondrogenesis via transition from an initial N-cadherin-contributing stage to a succedent fibronectin-contributing stage during the process of chondrogenesis in MSCs. Further study is needed to evaluate whether or not it can promote chondrogenesis by transfecting cDNA of CAMs to MSCs.
Direct electron transfer reactions of cytochrome c at silver electrodes (1987)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDirect electron transfer reactions of cytochrome c at silver electrodesDavid E. Reed and Fred M. HawkridgeCite this: Anal. Chem. 1987, 59, 19, 2334–2339Publication Date (Print):October 1, 1987Publication History Published online1 May 2002Published inissue 1 October 1987https://pubs.acs.org/doi/10.1021/ac00146a005https://doi.org/10.1021/ac00146a005research-articleACS PublicationsRequest reuse permissionsArticle Views471Altmetric-Citations117LEARN 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 Get e-Alerts
Varied morphology carbon nanotubes and method for their manufacture (2023)

The present invention describes the preparation of carbon nanotubes of varied morphology, catalyst materials for their synthesis. The present invention also describes reactor apparatus and methods of optimizing and controlling process parameters for the manufacture carbon nanotubes with pre-determined morphologies in relatively high purity and in high yields. In particular, the present invention provides methods for the preparation of non-aligned carbon nanotubes with controllable morphologies, catalyst materials and methods for their manufacture.
Directed Evolution of a Formate Dehydrogenase for Increased Tolerance to Ionic Liquids Reveals a New Site for Increasing the Stability (2014)

The formate dehydrogenase (FDH) from Candida boidinii is a well-known enzyme in biocatalysis for NADH regeneration. Nevertheless, it has low activity in a water-miscible ionic liquid (1,3-dimethylimidazolium dimethyl phosphate, [MMIm][Me2 PO4 ]). In this work, this enzyme was subjected to directed evolution by using error-prone PCR, and a mutant (N187S/T321S) displaying higher activity was obtained following selection based on the formazan-based colorimetric assay. The mutation N187S is responsible for improved activity both in aqueous solution and in [MMIm][Me2 PO4 ], through an enhancement of the kcat value by a factor of 5.8. Fluorescence experiments performed in the presence of a quenching agent revealed that the mutant does not unfold in the presence of 50 % (v/v) [MMIm][Me2 PO4 ] whereas the wild-type enzyme does. Molecular modelling revealed that the mutation is located at the monomer-monomer interface and causes an increase in the pKa of residue E163 from 4.8 to 5.5. Calculation of the pKa of this residue in other microbial FDHs showed that thermostable FDHs have a highly basic glutamate at this position (pKa up to 6.2). We have identified a new site for improving FDH thermostability and tolerance to ionic liquids, and it is linked to the local charge of the enzymes in this class.
Synthesis and Activity of 1,3,5-Triphenylimidazolidine-2,4-diones and 1,3,5-Triphenyl-2-thioxoimidazolidin-4-ones: Characterization of New CB<sub>1</sub> Cannabinoid Receptor Inverse Agonists/Antagonists (2006)

Obesity and metabolic syndrome, along with drug dependence (nicotine, alcohol, opiates), are two of the major therapeutic applications for CB(1) cannabinoid receptor antagonists and inverse agonists. In the present study, we report the synthesis and structure-affinity relationships of 1,5-diphenylimidazolidine-2,4-dione and 1,3,5-triphenylimidazolidine-2,4-dione derivatives. These new 1,3,5-triphenylimidazolidine-2,4-dione derivatives and their thio isosteres were obtained by an original pathway and exhibited interesting affinity and selectivity for the human CB(1) cannabinoid receptor. A [(35)S]-GTPgammaS binding assay revealed the inverse agonist properties of the compounds at the CB(1) cannabinoid receptor. Furthermore, molecular modeling studies were conducted in order to delineate the binding mode of this series of derivatives into the CB(1) cannabinoid receptor. 1,3-Bis(4-bromophenyl)-5-phenylimidazolidine-2,4-dione (25) and 1,3-bis(4-chlorophenyl)-5-phenylimidazolidine-2,4-dione (23) are the imidazolidine-2,4-dione derivatives possessing the highest affinity for the human CB(1) cannabinoid receptor reported to date.
Testing Bid Design Effects in Multiple-Bounded, Contingent-Valuation Questions (2002)

<i>Multiple-bounded, contingent-valuation questions have been proposed as an alternative to single-bounded and double-bounded questions. While the effects of bid design on multiple-bounded responses have not been explored, findings of experimental effects in single- and double-bounded questions make this a logical area of inquiry. We explore two potential experimental effects in multiple-bounded questions. Respondents may simply express welfare estimates in the center of the bid list. Also, the range of bids may systematically influence welfare estimates. We find while respondents do not center their responses, the range of bids influences welfare estimates and responses to individual bids.</i> (Q26)
A physiochemical processing kinetics model for the vapor phase infiltration of polymers: measuring the energetics of precursor-polymer sorption, diffusion, and reaction (2018)

Vapor phase infiltration (VPI) is a new approach for transforming polymers into organic-inorganic hybrid materials with unique properties. Here, we combine experimental measurements with phenomenological theory to develop a universal strategy for measuring, modeling, and predicting the processing kinetics of VPI. We apply our approach to the well-studied VPI system of trimethylaluminum (TMA) infiltrating poly(methyl methacrylate) (PMMA) because the system undergoes both precursor-polymer diffusion and reaction. By experimentally measuring aluminum concentration profiles as a function of film depth with secondary ion mass spectrometry (SIMS) and film swelling with ellipsometry, we have extracted equilibrium solubility and effective diffusivity as a function of process temperature. Fitting these values to appropriate Van't Hoff and Arrhenius relationships, we can then extract enthalpies for precursor sorption and diffusion. We observe an abrupt mechanistic change in both the sorption and diffusion processes around 95 °C, where greater chain mobility at higher processing temperatures lead to greater reactivity between TMA and PMMA. With new understanding of this VPI process, we demonstrate precise control of inorganic infiltration depth and loading fraction into PMMA.
A novel microprocessor-controlled active-R multifunction network: design of programmable filter, oscillator, and FSK/PSK wave generator (1990)

A two-operational amplifier (OA) active-R network with multifilter/oscillator functional capability is described. Analysis indicates the availability of bandpass (BP), low-pass (LP), band-reject (BR), all-pass (AP), and sinusoidal oscillator functions at extended frequency range with low sensitivity. Design equations and expressions for frequency stability and sensitivity are derived. Designs for both continuous and digitally programmable control of the network parameters using appropriate switched resistors have been derived and verified experimentally. The scanning of a typical band (50-200 kHz with mu A/LM 741 and 200-1000 kHz with LF 356 OAs) at certain programmable center frequencies has been verified experimentally while setting Q=10 with an appropriate resistor switching sequence generated by the microprocessor.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Clinical Utility of Bilateral Whole-Breast US in the Evaluation of Women with Dense Breast Tissue (2001)

Bilateral whole-breast US, when performed in patients with dense (BI-RADS category 3 or 4 density) breast tissue, is useful in detecting breast cancer not discovered with mammography or clinical breast examination. The 0.3% cancer detection rate compares favorably with that of screening mammography and with that in previously published studies involving bilateral whole-breast US.