gebhart/patrepeval huggingface dataset:
Imaging evaluation of CsI(Tl) arrays for scintimammography (2002)

We propose the use of Hamamatsu R7600-C8 position sensitive photomultiplier tubes (PSPMTs) as a practical tool for imaging in scintimammography, through the evaluation of performance as a function of scintillation array pixellation in collimated configurations. A number of CsI(Tl) scintillating arrays with different pixel size and thickness are tested. The very high intrinsic spatial resolution of R7600 PSPMTs made it easy to implement a look up table to correct accurately the gain nonuniformity response and position distortion. Finally, an SNR analysis of a small tumor in scintimammography as a function of crystal pixellation is performed by means of a simple breast phantom.
Sustained<i>ex vivo</i>expansion of hematopoietic stem cells mediated by thrombopoietin (1999)

The hematopoietic stem cell (HSC) is defined as a cell that can either self-replicate or generate daughter cells that are destined to commit to mature cells of different specific lineages. Self-replication of the most primitive HSC produces daughter cells that possess a long (possibly unlimited) clonal lifespan, whereas differentiation of HSC produces daughter cells that demonstrate a progressive reduction of their clonal lifespan, a loss of multilineage potential, and lineage commitment. Previous studies indicated that the proliferation of HSC ex vivo favors differentiation at the expense of self-replication, eventually resulting in a complete loss of HSC. In contrast, transplantation studies have shown that a single HSC can repopulate the marrow of a lethally irradiated mouse, demonstrating that self-renewal of HSC occurs in vivo. Thrombopoietin (TPO) has been shown to function both as a proliferative and differentiative factor for megakaryocytes and as a survival and weakly proliferative factor for HSC. Our studies focused on the effects of exogenous TPO on HSC in mouse long-term bone marrow cultures (LTBMC). Previous results indicate that HSC decline in LTBMC in the absence of TPO. In contrast, the continuous presence of TPO resulted in the generation of both long- and short-term repopulating HSC as detected by an in vivo competitive repopulation assay. HSC were generated over a 4-month period at concentrations similar to normal bone marrow. Our results demonstrate that TPO can mediate the self-replication of HSC in LTBMC, and provide proof that HSC can self-replicate ex vivo.
Particle grouping in standing and moving wave velocity fields (2010)

The parameters which control particle grouping characteristics in a standing wave velocity field are elucidated. A mathematical model for particle grouping in a standing wave velocity field is compared with the one describing their grouping in a moving wave velocity field. Two grouping/non-grouping regimes are identified and described. It is pointed out that particle flow in a standing wave velocity field has a smaller range of operating conditions, where grouping is expected, compared with the particle flow in the moving wave.
Selective Averaging of Evoked Potentials using Trajectory-Based Clustering (1994)

A clustering method has been developed to group evoked potentials that display similar prestimulus dynamic behavior. The procedure involves using the method of time delay embedding to construct a trajectory in state space from a time series. Certain features that characterize the geometry of the trajectory have been defined. The trajectory-based clustering algorithm has been applied to visual evoked potentials to determine relationships between prestimulus EEG and evoked potential shape.
Dielectric Property Measurement of Insulating Paper by the Gap Variation Method (1968)

A brief convenient method of examining the characteristics of the dielectric properties of paper specimens, and the experimental results using the gap variation method are · presented. The dielectric property measurement of paper specimens as thin as 30 microns is possible. Paper specimens of such a size can be measured one sheet at a time and need not be stacked to be measured, as is the case with conventional methods. The dielectric properties of a specimen that is kept air tight in a thinfilm polymer pouch can be measured with no effects from the ambient atmosphere.
Functional Specialization of Maize Mitochondrial Aldehyde Dehydrogenases (2002)

The maize (Zea mays) rf2a and rf2b genes both encode homotetrameric aldehyde dehydrogenases (ALDHs). The RF2A protein was shown previously to accumulate in the mitochondria. In vitro import experiments and ALDH assays on mitochondrial extracts from rf2a mutant plants established that the RF2B protein also accumulates in the mitochondria. RNA gel-blot analyses and immunohistolocation experiments revealed that these two proteins have only partially redundant expression patterns in organs and cell types. For example, RF2A, but not RF2B, accumulates to high levels in the tapetal cells of anthers. Kinetic analyses established that RF2A and RF2B have quite different substrate specificities; although RF2A can oxidize a broad range of aldehydes, including aliphatic aldehydes and aromatic aldehydes, RF2B can oxidize only short-chain aliphatic aldehydes. These two enzymes also have different pH optima and responses to changes in substrate concentration. In addition, RF2A, but not RF2B or any other natural ALDHs, exhibits positive cooperativity. These functional specializations may explain why many species have two mitochondrial ALDHs. This study provides data that serve as a basis for identifying the physiological pathway by which the rf2a gene participates in normal anther development and the restoration of Texas cytoplasm-based male sterility. For example, the observations that Texas cytoplasm anthers do not accumulate elevated levels of reactive oxygen species or lipid peroxidation and the kinetic features of RF2A make it unlikely that rf2a restores fertility by preventing premature programmed cell death.
Interlaboratory Verified Liquid Chromatographic Method for Analysis of Vitamins A and E in Soy-Based Infant Formula Powder (2004)

An interlaboratory verified, liquid chromatographic (LC) method is presented for the analysis of all-rac-alpha-tocopheryl acetate and retinyl palmitate in soy-based infant formula. The extraction procedure uses sample dehydration with magnesium sulfate followed by extraction with isopropanol, hexane-ethyl acetate (85 + 15, v/v). After evaporation and filtration, the sample extract is injected directly onto a normal-phase LC system with fluorescence detection. All-rac-alpha-tocopheryl acetate and retinyl palmitate are quantitated isocratically with a mobile phase of hexane containing 0.50% (v/v) and 0.125% (v/v) isopropanol, respectively. A zero control reference material (ZRM) was spiked at 5 levels, with 5 replicate analyses of 1/2x, x, 2x, 4x, and 16x where "x" is the minimum level of 250 IU/100 kcal (vitamin A) and 0.7 IU/100 kcal (vitamin E) as specified in 21 Code of Federal Regulations 107.100. The following recoveries and RSD values represent an average (n = 25) of the 5 levels for each analyte: all-rac-alpha-tocopheryl acetate, 100% (RSD = 3.5%); retinyl palmitate, 97.2% (RSD = 2.1%). Two additional laboratories analyzed the fortified ZRM samples. Average recoveries (n = 24) of all-rac-alpha-tocopheryl acetate and retinyl palmitate at 4 levels were all-rac-alpha-tocopheryl acetate, 99.0% (RSD = 4.0%), and retinyl palmitate, 96.2% (RSD = 1.4%) at the second laboratory. Average recoveries (n = 24) of all-rac-alpha-tocopheryl acetate and retinyl palmitate at 4 levels were all-rac-alpha-tocopheryl acetate, 102% (RSD = 1.4%) and retinyl palmitate, 95.7% (RSD = 2.0%) at the third laboratory. In addition, 6 replicates of the same commercial soy-based infant formula powder were run by the 3 laboratories.
7-Deazapurine 2'-deoxyribofuranosides are noncleavable competitive inhibitors of Escherichia coli purine nucleoside phosphorylase (PNP). (1998)

A series of 7-deazapurine 2'-deoxyribofuranosides were synthesized according to already known procedures and their substrate and inhibitor properties with purified E. coli purine nucleoside phosphorylase were examined. In agreement with previous findings, substrate activity was not detected for any of the compounds tested. Most of the nucleosides showed weak inhibition in the preliminary screening, i.e. at a concentration of about 100 microM. However some combinations of 6-chloro, 6-amino or 6-methoxy substituents with bulky hydrophobic groups at position 7 of the base and/or chloro, amino, methoxy or methylthio group at position 2 markedly enhanced affinity of such modified nucleosides for the E. coli enzyme. The most potent inhibition was observed for two nucleosides: 6-chloro- and 2-amino-6-chloro-7-deazapurine 2'-deoxyribofuranosides that show inhibition constants Ki = 2.4 and 2.3 microM, respectively. Several other compounds were also found to be good inhibitors, with inhibition constants in the range 5-50 microM. In all instances the inhibition was competitive vs. the nucleoside substrate 7-methylguanosine. Inhibition constants for 7-deazapurine nucleosides are in general several-fold lower than those observed for their purine counterparts. Therefore 7-deaza modification together with substitutions at positions 2, 6 and 7 of the base is a very promising approach to obtain competitive noncleavable inhibitors of E. coli PNP that may bind to the enzyme with inhibition constants in the microM range.
Method for non-invasive hemoglobin oxygen saturation measurement using broadband light source and color filters (2019)

A non-invasive optical measurement system based on a broadband light source and color filters has been developed for determining pulse rate and arterial blood oxygen saturation (SaO2). In contrast to classical pulse oximetry using red and infrared LEDs to measure the peripheral capillary oxygen saturation (SpO2), we use color filters in our system. Spectral analysis of human tissue can be easily achieved by combining a tiny color filter matrix and a commercial CMOS/CCD image sensor. During system operation, white LED light illuminates our tissue (e.g., a finger), while a CCD sensor covered by filters detects the light transmitted through that tissue. The CCD sensor is controlled by a Field Programmable Gate Array (FPGA) and a microcontroller. The detected photoplethysmographic (PPG) signal is transferred to a host computer and analyzed with MATLAB. After sensor system calibration, pulse rate and SpO2 can be simply extracted from the PPG signal. The heart rate and SpO2 of different volunteers are then measured simultaneously by commercial pulse oximetry and the proposed sensor system, in which results from both devices show good agreement. To integrate more functions into system, nanostructured color filter matrix containing 15 filters for different wavelengths is designed and fabricated. This filter can be designed to provide transmission peaks over the visible and near-infrared range (i.e., the human tissue optical transparent window) and has a high potential to be fabricated directly on top of pixels of an image sensor.
Atomic absorption of arsenic in nitrogen (entrained air)-hydrogen flames (1969)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAtomic absorption of arsenic in nitrogen (entrained air)-hydrogen flamesAtsushi. Ando, Masami. Suzuki, Keiichiro. Fuwa, and Bert L. ValleeCite this: Anal. Chem. 1969, 41, 14, 1974–1979Publication Date (Print):December 1, 1969Publication History Published online1 May 2002Published inissue 1 December 1969https://pubs.acs.org/doi/10.1021/ac50159a031https://doi.org/10.1021/ac50159a031research-articleACS PublicationsRequest reuse permissionsArticle Views59Altmetric-Citations15LEARN 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
Gene–Environment Interaction in Yeast Gene Expression (2008)

The effects of genetic variants on phenotypic traits often depend on environmental and physiological conditions, but such gene-environment interactions are poorly understood. Recently developed approaches that treat transcript abundances of thousands of genes as quantitative traits offer the opportunity to broadly characterize the architecture of gene-environment interactions. We examined the genetic and molecular basis of variation in gene expression between two yeast strains (BY and RM) grown in two different conditions (glucose and ethanol as carbon sources). We observed that most transcripts vary by strain and condition, with 2,996, 3,448, and 2,037 transcripts showing significant strain, condition, and strain-condition interaction effects, respectively. We expression profiled over 100 segregants derived from a cross between BY and RM in both growth conditions, and identified 1,555 linkages for 1,382 transcripts that show significant gene-environment interaction. At the locus level, local linkages, which usually correspond to polymorphisms in cis-regulatory elements, tend to be more stable across conditions, such that they are more likely to show the same effect or the same direction of effect across conditions. Distant linkages, which usually correspond to polymorphisms influencing trans-acting factors, are more condition-dependent, and often show effects in different directions in the two conditions. We characterized a locus that influences expression of many growth-related transcripts, and showed that the majority of the variation is explained by polymorphism in the gene IRA2. The RM allele of IRA2 appears to inhibit Ras/PKA signaling more strongly than the BY allele, and has undergone a change in selective pressure. Our results provide a broad overview of the genetic architecture of gene-environment interactions, as well as a detailed molecular example, and lead to key insights into how the effects of different classes of regulatory variants are modulated by the environment. These observations will guide the design of studies aimed at understanding the genetic basis of complex traits.
Internal jugular vein thrombosis detection by ultrasound scan after failure of internal jugular vein catheterization -A case report- (2008)

Right internal jugular vein catheterization is performed frequently as central venous catheterization by the landmark method. This procedure, however, might prove difficulty due to anatomic variations or thrombosis of internal jugular vein. We failed to catheterize right internal jugular vein by the landmark method in 70-year-old female patient. And then, we detected right internal jugular vein thrombosis by ultrasound scan. Left internal jugular vein catheterization was performed by the ultrasound guided technique. Central venous catheterization has possibility to fail despite several attempts by the landmark method. Then, ultrasound guided approach is a good choice to aid central venous catheterization when difficulties or complications have been encountered. (
Metabolism of all-trans-retinoic acid by cultured human epidermal keratinocytes (1997)

The uptake and metabolism of exogenous all-trans-retinoic acid by human epidermal keratinocytes in submerged culture was examined. Retinoic acid presented to keratinocytes in physiological form bound to albumin was rapidly taken up. Peak cellular concentrations were achieved within 1 h and were 50- to 100-fold higher than that in medium. Retinoic acid metabolism was less rapid but was vigorous, exhibiting a half-life of 6 h. Neither uptake nor metabolism was saturable at medium retinoic acid concentrations up to 1 microM. Eighty-five percent of retinoic acid was metabolized to unidentified polar compounds which were excreted from cells to the medium. The production and clearance of the polar metabolites was inhibited 60% by 10 microM ketoconazole. Fifteen percent of intracellular retinoic acid was converted to 3,4-didehydroretinoic acid, was proportional to cellular retinoic acid concentration, and was not affected by ketoconazole. Cellular retinyl ester content, which is sensitive to exogenous retinoic acid, was correlated with both the concentration and the quantity, of retinoic acid in the culture system. These results suggest that the metabolism of retinoic acid in keratinocytes is substrate limited and has potential to limit the availability of exogenous retinoic acid for retinoid signaling.
CovR and VicRKX Regulate Transcription of the Collagen Binding Protein Cnm of Streptococcus mutans (2018)

Cnm is a surface-associated protein present in a subset of <i>Streptococcus mutans</i> strains that mediates binding to extracellular matrices, intracellular invasion, and virulence. Here, we showed that <i>cnm</i> transcription is controlled by the global regulators CovR and VicRKX. <i>In silico</i> analysis identified multiple putative CovR- and VicR-binding motifs in the regulatory region of <i>cnm</i> as well as in the downstream gene <i>pgfS</i>, which is associated with the posttranslational modification of Cnm. Electrophoretic mobility shift assays revealed that CovR and VicR specifically and independently bind to the <i>cnm</i> and <i>pgfS</i> promoter regions. Quantitative real-time PCR and Western blot analyses of Δ<i>covR</i> and Δ<i>vicK</i> strains as well as of a strain overexpressing <i>vicRKX</i> revealed that CovR functions as a positive regulator of <i>cnm</i>, whereas VicRKX acts as a negative regulator. In agreement with the role of VicRKX as a repressor, the Δ<i>vicK</i> strain showed enhanced binding to collagen and laminin and higher intracellular invasion rates. Overexpression of <i>vicRKX</i> was associated with decreased rates of intracellular invasion but did not affect collagen or lamin binding activities, suggesting that this system controls additional genes involved in binding to these extracellular matrix proteins. As expected, based on the role of CovR in <i>cnm</i> regulation, the Δ<i>covR</i> strain showed decreased intracellular invasion rates, but, unexpectedly collagen and laminin binding activities were increased in this mutant strain. Collectively, the results presented here expand the repertoire of virulence-related genes regulated by CovR and VicRKX to include the core gene <i>pgfS</i> and the noncore gene <i>cnm</i><b>IMPORTANCE</b><i>Streptococcus mutans</i> is a major pathogen associated with dental caries and also implicated in systemic infections, in particular, infective endocarditis. The Cnm adhesin of <i>S. mutans</i> is an important virulence factor associated with systemic infections and caries severity. Despite its role in virulence, the regulatory mechanisms governing <i>cnm</i> expression are poorly understood. Here, we describe the identification of two independent regulatory systems controlling the transcription of <i>cnm</i> and the downstream <i>pgfS-pgfM1-pgfE-pgfM2</i> operon. A better understanding of the mechanisms controlling expression of virulence factors like Cnm can facilitate the development of new strategies to treat bacterial infections.
System prasowy Chorwacji (2003)

The press system in Croatia is among the youngest media systems in Europe. It is based on relatively peculiar constitutional provisions that make the right to rectification a principle. The Croatian system meets the requirements of a press system posed by the European Union and Community regulations. It comprises detailed provisions concerning the freedom of press, the principles of registration of press activity, the rights and obligations of journalists, rectifications and replies.
A New Concept of Synthetic Aperture Instrument for High Resolution Earth Observation from High Orbits (2005)

High Resolution Earth Observation from high orbits (e.g. Geostationnary) requires the use of large diameter telescopes, unfeasible if considering monolithic concepts. It is necessary, to circumvent this problem, to consider a segmented instrument, turning it into a feasible concept that can be put into orbit. Optical Aperture Synthesis (OAS) can be considered as a solution for HR observation from high orbits. In this paper, we describe a new OAS imaging instrument concept (under study in the Alcatel Space Research Department [1]) having variable resolution and field of view by adopting a re-decomposition of the basic Michelson or Fizeau interferometer schemes. In addition to providing variable resolution power and field of view, this instrument concept is particularly robust to sub-systems failure since it shows a natural redundancy of its imaging capabilities.
STORM: A General Model to Determine the Number and Adaptive Changes of Epithelial Stem Cells in Teleost, Murine and Human Intestinal Tracts (2010)

Intestinal stem cells play a pivotal role in the epithelial tissue renewal, homeostasis and cancer development. The lack of a general marker for intestinal stem cells across species has hampered analysis of stem cell number in different species and their adaptive changes upon intestinal lesions or during development of cancer. Here a two-dimensional model, named STORM, has been developed to address this issue. By optimizing epithelium renewal dynamics, the model examines the epithelial stem cell number by taking experimental input information regarding epithelium proliferation and differentiation. As the results suggest, there are 2.0-4.1 epithelial stem cells on each pocket section of zebrafish intestine, 2.0-4.1 stem cells on each crypt section of murine small intestine and 1.8-3.5 stem cells on each crypt section of human duodenum. The model is able to provide quick results for stem cell number and its adaptive changes, which is not easy to measure through experiments. Its general applicability to different species makes it a valuable tool for analysis of intestinal stem cells under various pathological conditions.
Synthesis and Characterization of 2, 3-Dihydroxypropylcellulose (1988)

Abstract Water-soluble 2,3-dihydroxypropylcellulose (DHPC) was successfully synthesized by the reaction of 3-chloro-1,2-propanediol with alkali cellulose in dioxane, or with glycidol in acetone. DHPC from the glycidol reaction was shown to have better solubility and yield. DHPC made from cotton wool and glycidol possesses the highest intrinsic visocisty (up to 4.05 dL/g). Quantitative 13 C-NMR analysis was utilized to estimate the molar substitution and degree of substitution of the resulting DHPC. Since the ratios of molar substitution to degree of substitution were found to be 2 or less, the substituents on the cellulose probably consist of monomer, dimer, or trimer of the alkylation agents used. Above the critical concentration of DHPC, the solution viscosity was found to be increased tremendously upon treating with boric acid under basic conditions.