gebhart/patrepeval huggingface dataset:
Is <i>Trichomonas vaginalis</i> a Cause of Cervical Neoplasia? Results from a Combined Analysis of 24 Studies (1994)

BackgroundWe conducted this combined analysis of available data from studies with information on this issue to clarify the association between Trichomonas vaginalis infection and cervical neoplasia. MethodsWe performed MEDLINE searches (1966–1993) uslng the key words and phrases ‘trichomonas vaginitis’ and ‘neoplasms, cervix’ for articles published in English, and searched citations of the articles obtained from MEDLINE. A total of 24 articles (two cohort studies and 22 case-control) were included in this data analysis. In the analysis, the studies were evaluated for heterogeneity using Breslow-Day tests for homogeneity of the odds ratios and of rate ratios. If the odds ratios from studies are heterogeneous, it is not appropriate to combine them using the Mantel-Haenszel method. Also, publication bias was evaluated by assessing the association between the observed effect size and the variance of the effect size using a rank correlation test. ResultsThe combined summary relative risk for the two cohort studies was 1.93 (95% confidence interval: 1.22–2.65) indicating an approximate doubling of the risk of cervical neoplasia in the presence of T. vaginalis infection. The attributable risks among exposed subjects and among the source population were 47.4% and 2.1% respectively. Results of the 22 retrospective studies were much less consistent However, most of them demonstrated a significant positive association. ConclusionsThis combined analysis suggests that there is an association between T. vaginalis and the risk of cervical neoplasia, but that such infections account for only 2% of cervical neoplasia.
Expression and activity of PXR target genes CYP3A4 and MDR1 in sarcoma tumors predict response to chemotherapeutic agents (2004)

4754 Objectives: We tested the hypothesis that orphan steroid pregnane X receptor (PXR) modulation of target genes involved in drug metabolism and transport may be involved in drug resistance of sarcomas. We examined cytotoxicity, inducibility, expression and activity of CYP3A4/5 and the multidrug resistance gene (MDR1) using a specific PXR ligand, rifampin, and selected chemotherapeutic agents in primary sarcoma cell lines. Methods: Total RNA from primary sarcoma cell lines was extracted before and after exposure to etoposide, doxorubicin, ifosfamide, rifampin or phenobarbitol and real-time PCR assays carried out for CYP3A4/5, PXR and MDR1. Protein expression was measured by western blot analysis. Catalytic activity of CYP3A was measured using 7-benzyl-trifluoromethyl coumarin, a CYP3A specific substrate, and/or testosterone 6β-hydroxylation, and a rhodamine 123 assay was used to measure MDR1 activity. Cytotoxicity was determined by lactate dehydrogenase release, Bax/Bcl-2 ratios and PARP cleavage and/or annexin V staining. Results: We observed variations in baseline gene and protein expression of CYP3A4/5, PXR and MDR1 in the different primary sarcoma cell lines. Furthermore, differences were observed in the induction, expression and activity of CYP3A4/5 and MDR1 in response to the PXR specific ligand, rifampin, and the xenobiotics mentioned above, which correlate with the cytotoxic effects of the chemotherapeutic agents. Our results suggest substantial differences in the cytotoxicity profile mediated by these genes. Resistance of primary sarcoma cell lines to etoposide correlated best with increased CYP3A activity and PXR protein expression. Interestingly, while rifampin showed a selective increase in CYP3A activity without any cytotoxic effect, etoposide induced CYP3A activity with variable cytotoxicity in sarcoma cell lines much more efficiently than rifampin, and the activity was reversible by ketoconazole, a CYP3A4 inhibitor. MDR1 expression and function in tumor cells correlated with resistance to doxorubicin, while ifosfamide sensitivity correlated best with baseline CYP3A activity in the tumor. Conclusion: We speculate that one mechanism of etoposide resistance in sarcoma occurs due to binding on PXR and conclude that expression and functional activity of PXR and target genes CYP3A4 and MDR1 in sarcoma tumors may play an important role in resistance and may be used as biomarkers of therapeutic response.
Comments on Some Recent Developments in the Field of Liquid Crystals (1981)

Abstract Three areas of research into liquid crystals which have seen considerable development since the last International Liquid Crystal Conference at Bordeaux in 1978 have been selected for a brief over-view. These areas concern: 1. New Liquid Crystal Materials containing non-aromatic ring systems and the developments which have followed from the earlier studies of esters of trans-4-n-alkylcyclohexane-1-carboxylic acids and the trans-4-n-alkyl-l-(4′-cyanopheny1)cyclohexanes (PCH's).2. Agreement over a Nomenclature Problem Concerning Smectic Polymorphs and some interesting features of the smectic phase sequences for the 4-n-alkoxybenzylidene-4′-n-alkylanilines.3. Discotic Phases—the discovery that the historically well known mesophase of di-isobutyl-silandiol is a discotic liquid crystal phase and the progress being made in studies of other discotic systems.
Use of mind maps and iterative decision trees to develop a guideline-based clinical decision support system for routine surgical practice: case study in thyroid nodules (2019)

The present study demonstrated that a knowledge-based CDSS is feasible in the treatment of thyroid nodules. A high-quality knowledge-based CDSS was developed, and medical domain and computer scientists collaborated effectively in an integrated development environment. The mind map and IDT approach represents a pioneering method of integrating knowledge from CPGs.
Unlocking the Secrets for Viable and Sustainable Shale Gas Development (2010)

Abstract In shale plays where horizontal wells are often required to achieve profitability, a common industry practice is to start evaluation of a prospect by drilling vertical or low-angle wells. Extensive formation evaluation measurements, which are then used as points of reference are then run. Interpretation data acquired from vertical wells is used to describe the local reservoir and determine horizontal well placement objectives. Horizon depths may be adjusted for depth based on surface seismic or observations from other wells, otherwise formation properties in the horizontal are considered to be invariant. Acquiring formation evaluation measurements along the lateral is often considered to provide little additional value, are not worth the extra rig time, risk, additional cost, and difficulties associated with tool conveyance. These wellbores typically will be stimulated to test production or converted to a horizontal well via sidetracking. Horizontal wells are commonly steered using simple gamma-ray measurements correlated with the vertical pilot wells. Detailed examination has revealed that steering results for horizontal wells, using averaged gamma ray correlation techniques and subsequent structural modeling, yield non-unique solutions. This may result in less than optimum reservoir exposure over the drilled interval. With the integration of Logging While Drilling (LWD) technology into the Bottom Hole Assembly (BHA), real-time formation evaluation measurements provide key information for detailed rock property assessment across the target structure, consistent with pilot or offset well evaluation methods, and facilitate accurate well placement. Additionally, real-time and pseudo real-time LWD measurements have been successfully used for hazard avoidance, enhanced penetration rates reducing drilling time, and most importantly completion design optimization. While the LWD method offers some appreciation for the inconsistent rock quality and variable production results across wells, it also provides conclusive insight into the reservoir-production relationship. Understanding of this relationship provides for target refinement within the reservoir column and an optimized completion for an overall increase in reserve recovery. This paper investigates the use of gamma ray-only measurements only for evaluation and geosteering, and then details the geosteering application using more robust formation evaluation and the subsequent completion optimization. Results are verified using micro-seismic monitoring and production data within a shale gas play. In this manner, structural models, formation evaluation and completion designs are combined to form the technological foundation that can unlock the secrets for viable and sustainable shale gas development.
Self-organizing map in Matlab: the SOM Toolbox (1999)

The Self-Organizing Map (SOM) is a vector quantization method which places the prototype vectors on a regular low-dimensional grid in an ordered fashion. This makes the SOM a powerful visualization tool. The SOM Toolbox is an implementation of the SOM and its visualization in the Matlab 5 computing environment. In this article, the SOM Toolbox and its usage are shortly presented. Also its performance in terms of computational load is evaluated and compared to a corresponding C-program. 1. General This article presents the (second version of the) SOM Toolbox, hereafter simply called the Toolbox, for Matlab 5 computing environment by MathWorks, Inc. The SOM acronym stands for Self-Organizing Map (also called Self-Organizing Feature Map or Kohonen map), a popular neural network based on unsupervised learning [1]. The Toolbox contains functions for creation, visualization and analysis of Self-Organizing Maps. The Toolbox is available free of charge under the GNU General Public License from
Dielectric Constant Behavior of Hf-O-N System (2005)

The influence of nitrogen incorporation into HfO2 has been investigated in terms of film dielectric constant and film microstructure. Static dielectric constant did not increase linearly with an increase in nitrogen concentration ([N]=N/(Hf+O+N)), but plateaued from [N] values of approximately 9 to 22 at. %. The nonlinear behavior at [N]<18 at. % was well described by the Clausius–Mossotti equation using Shannon's model of the additivity rule of static polarizabilities. Hf–N binding energy from X-ray photoelectron spectroscopy (XPS), band gap energy from reflection electron energy loss spectroscopy (REELS), conduction band offset from REELS and XPS, and refractive index from ellipsometry showed marked differences between the case of [N] values greater and less than 18 at. %. We estimated figure of merits (F.O.M.) for various high-k gate dielectrics in terms of tunneling current suppression, and found that the Hf–O–N system in the [N] range of 7.6 to 16.1 at. % showed the highest F.O.M. among the region studied.
HIGH-TEMPERATURE CO-ELECTROLYSIS OF H2O AND CO2 FOR SYNGAS PRODUCTION (2006)

Worldwide, the demand for light hydrocarbon fuels like gasoline and diesel oil is increasing. To satisfy this demand, oil companies have begun to utilize oil deposits of lower hydrogen content (an example is the Athabasca Oil Sands). Additionally, the higher contents of sulfur and nitrogen of these resources requires processes such as hydrotreating to meet environmental requirements. In the mean time, with the price of oil currently over $50 / barrel, synthetically-derived hydrocarbon fuels (synfuels) have become economical. Synfuels are typically produced from syngas – hydrogen (H2) and carbon monoxide (CO) -- using the Fischer-Tropsch process, discovered by Germany before World War II. South Africa has used synfuels to power a significant number of their buses, trucks, and taxicabs. The Idaho National Laboratory (INL), in conjunction with Ceramatec Inc. (Salt Lake City, USA) has been researching for several years the use of solid-oxide fuel cell technology to electrolyze steam for large-scale nuclear-powered hydrogen production. Now, an experimental research project is underway at the INL to investigate the feasibility of producing syngas by simultaneously electrolyzing at high-temperature steam and carbon dioxide (CO2) using solid oxide fuel cell technology. The syngas can then be used for synthetic fuel production. This program is a combination of experimental and computational activities. Since the solid oxide electrolyte material is a conductor of oxygen ions, CO can be produced by electrolyzing CO2 sequestered from some greenhouse gas-emitting process. Under certain conditions, however, CO can further electrolyze to produce carbon, which can then deposit on cell surfaces and reduce cell performance. The understanding of the co-electrolysis of steam and CO2 is also complicated by the competing water-gas shift reaction. Results of experiments and calculations to date of CO2 and CO2/H2O electrolysis will be presented and discussed. These will include electrolysis performance at various temperatures, gas mixtures, and electrical settings. Product gas compositions, as measured via a gas analyser, and their relationship to conversion efficiencies will be presented. These measurements will be compared to predictions obtained from chemical equilibrium computer codes. Better understanding of the feasibility of producing syngas using high-temperature electrolysis will initiate the systematic investigation of nuclear-powered synfuel production as a bridge to the future hydrogen economy and ultimate independence from foreign energy resources.
Acetylacetone: A versatile ligand (1989)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAcetylacetone: A versatile ligandMiquel Seco Cite this: J. Chem. Educ. 1989, 66, 9, 779Publication Date (Print):September 1, 1989Publication History Received3 August 2009Published online1 September 1989Published inissue 1 September 1989https://doi.org/10.1021/ed066p779Request reuse permissionsArticle Views5022Altmetric-Citations10LEARN 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 InReddit PDF (1 MB) Get e-Alertsclose Get e-Alerts
SHEAR DEPENDENCE IN THE VISCOMETRY OF HIGH POLYMER SOLUTIONS: A NEW VARIABLE-SHEAR CAPILLARY VISCOMETER (1961)

The principles of capillary viscometry are reviewed, and design criteria for capillary viscometers to be used with non-Newtonian liquids are discussed. A description is given of a new type of variable-shear capillary viscometer—a modification of the Ubbelohde suspended-level viscometer—designed for measurements in the low-shear range. The instrument is rugged, convenient, and precise, and makes possible measurements at free fall over a 10-fold range of shear stress (or shear rate), a range that can easily be extended by use of two or more suitably modified instruments or by the application of external pressure. Experimental evidence is presented to show that proper choice of the dimensions of the instrument eliminates or minimizes most of the "effects" that limit the precision of measurements of relative viscosity (and related functions) of high polymer solutions in the range of low shear stresses.
Recovery of lost or erroneously received motion vectors (1993)

A technique using boundary matching to compensate for lost or erroneously received motion vectors in motion-compensated video coding is proposed. This technique, called the boundary matching algorithm, produces noticeably better results than those reported previously. It is first assumed that the displaced frame differences have no error. Then, this assumption is relaxed by proposing an algorithm (the extended boundary matching algorithm or EBMA) which can recover both the missing displaced frame differences and the missing motion vectors. The resulting images obtained using these methods and some other methods are compared. The images obtained clearly show that better image quality can be obtained by EBMA.< <ETX>></ETX>
An Osmosensing Signal Transduction Pathway in Yeast (1993)

Yeast genes were isolated that are required for restoring the osmotic gradient across the cell membrane in response to increased external osmolarity. Two of these genes, HOG1 and PBS2, encode members of the mitogen-activated protein kinase (MAP kinase) and MAP kinase kinase gene families, respectively. MAP kinases are activated by extracellular ligands such as growth factors and function as intermediate kinases in protein phosphorylation cascades. A rapid, PBS2-dependent tyrosine phosphorylation of HOG1 protein occurred in response to increases in extracellular osmolarity. These data define a signal transduction pathway that is activated by changes in the osmolarity of the extracellular environment.
Early Gene Responses to Transforming Growth Factor-β in Cells Lacking Growth-Suppressive RB Function (1991)

The growth-suppressive function of the retinoblastoma susceptibility gene product, RB, has been implicated in the mediation of growth inhibition and negative regulation of certain proliferation related genes by transforming growth factor-beta 1 (TGF-beta 1). Early gene responses to TGF-beta 1 were examined in order to determine their dependence on the cell cycle and on the growth-suppressive function of RB. TGF-beta 1, which rapidly elevates the steady-state level of junB and PAI-1 mRNAs and decreases that of c-myc mRNA, induces these responses in S-phase populations of Mv1Lu lung epithelial cells containing RB in a phosphorylated state. Since in this state RB is presumed to lack growth-suppressive activity, the response to TGF-beta 1 was also examined in DU145 human prostate carcinoma cells whose mutant RB product lacks growth-suppressive function. In these cells, TGF-beta 1 also decreases c-myc expression at the transcription initiation level. These results suggests that the c-myc, junB, and PAI-1 responses to TGF-beta 1 are not restricted to the G1 phase of the cell cycle and that down-regulation of c-myc expression by TGF-beta 1 can occur through a mechanism independent from the growth-suppressive function of RB.
SiC devices: physics and numerical simulation (1994)

The important material parameters for 6H silicon carbide (6H-SiC) are extracted from the literature and implemented into the 2-D device simulation programs PISCES and BREAKDOWN and into the 1-D program OSSI Simulations of 6H-SiC p-n junctions show the possibility to operate corresponding devices at temperatures up to 1000 K thanks to their low reverse current densities. Comparison of a 6H-SiC 1200 V p-n/sup -/-n/sup +/ diode with a corresponding silicon (Si) diode shows the higher switching performance of the 6H-SiC diode, while the forward power loss is somewhat higher than in Si due to the higher built-in voltage of the 6H-SiC p-n junction. This disadvantage can be avoided by a 6H-SiC Schottky diode. The on-resistances of Si, 3C-SiC, and 6H-SiC vertical power MOSFET's are compared by analytical calculations. At room temperature, such SiC MOSFET's can operate up to blocking capabilities of 5000 V with an on-resistance below 0.1 /spl Omega/cm/sup 2/, while Si MOSFET's are limited to below 500 V. This is checked by calculating the characteristics of a 6H-SiC 1200 V MOSFET with PISCES. In the voltage region below 200 V, Si is superior due to its higher mobility and lower threshold voltage. Electric fields in the order of 4/spl times/10/sup 6/ V/cm occur in the gate oxide of the mentioned 6H-SiC MOSFET as well as in a field plate oxide used to passivate its planar junction. To investigate the high frequency performance of SiC devices, a heterobipolartransistor with a 6H-SiC emitter is considered. Base and collector are assumed to be out of 3C-SiC. Frequencies up to 10 GHz with a very high output power are obtained on the basis of analytical considerations.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Peptoids on Steroids: Precise Multivalent Estradiol–Peptidomimetic Conjugates Generated <i>via</i> Azide–Alkyne [3+2] Cycloaddition Reactions (2007)

Abstract We have developed a family of functionalized peptidomimetic oligomers for the multivalent display of bioactive ligands in a site‐directed manner. Sequence‐specific N ‐substituted glycine peptoid oligomer scaffolds were synthesized on solid phase to include up to six azidoalkyl sidechains. These constructs were used as substrates for Cu(I)‐catalyzed azide–alkyne [3+2] cycloaddition reactions. 17α‐ethynylestradiol was conjugated at up to six positions along the peptoid backbone, generating estradiol–peptidomimetic conjugates in good yield. We evaluate how the binding avidities of these compounds to the estrogen receptor are enhanced when the valency of hormone ligand presentation is increased.
Aggregation behavior of two spheres falling through an aging fluid (2006)

We study the behavior of two spheres that settle along their line of center in a yield stress fluid that "ages:" a Laponite suspension. In such a fluid, the fluid flow behind a falling single particle can either exhibit a negative wake, i.e., an upward motion, or not, according to the stress exerted by the particle on the fluid. We show that, if their initial separation distance is smaller than 15 radii, two identical particles cluster whatever the wake's structure. In addition, in the conditions within which a negative wake is observed, we evidence an unexpected lateral motion of the spheres.