gebhart/patrepeval huggingface dataset:
Visual and Colorimetric Lithium Ion Sensing Based on Digital Color Analysis (1999)

A new optical analytical method, "Digital Color Analysis (DCA)", is proposed based on a digital color analyzer instead of the conventional optical methodology, "Spectrophotometry". The digital color analyzer is a hand-held-size instrument for measuring "colors", and it can transform the color information into numerical values, color library data, etc., that can be treated as analytical information. DCA gives us a more informative analytical method than spectrophotometry by treating colors as digital information. In addition, DCA can also simulate the optimum color variations for optimization of the visual sensor with computer assistance. By utilizing colors as digital information, colorimetric analysis that has been used for only semiquantitative analysis can serve as an accurate determination method. On the basis of DCA, we developed a plasticized PVC film optode and a paper optode for Li+ determination in saliva. After the optimization of color variation and the detection range for the Li+ measurements, the optode membrane gives colorless gray in the Li+ therapeutic range (at 10(-3) M) in saliva. Consequently, whether or not the optimum therapeutic Li+ concentration is maintained can be easily evaluated with these optodes. Especially, the sensing paper optode can be easily handled within a short measurement time (approximately 80 s) which is suitable for home use. Using the digital color analyzer with QxQy coordinates, a linear relation calibration curve can be obtained over the range from 10(-5) to 10(-1) M Li+, in which the analyzer can detect a concentration difference of approximately 0.1 mM Li+. For the near future, an accurate and simple analysis is needed for a health check at home that does not require going to a hospital. The optode based on DCA has great potential for this analytical purpose.
Electrophilic Phosphonium Cation‐Mediated Phosphane Oxide Reduction Using Oxalyl Chloride and Hydrogen (2018)

The metal-free reduction of phosphane oxides with molecular hydrogen (H<sub>2</sub> ) using oxalyl chloride as activating agent was achieved. Quantum-mechanical investigations support the heterolytic splitting of H<sub>2</sub> by the in situ formed electrophilic phosphonium cation (EPC) and phosphane oxide and subsequent barrierless conversion to the phosphane and HCl. The reaction can also be catalyzed by the frustrated Lewis pair (FLP) consisting of B(2,6-F<sub>2</sub> C<sub>6</sub> H<sub>3</sub> )<sub>3</sub> and 2,6-lutidine or phosphane oxide as Lewis base. This novel reduction was demonstrated for triaryl and diaryl phosphane oxides providing access to phosphanes in good to excellent yields (51-93 %).
Halogenated furanones inhibit quorum sensing through accelerated LuxR turnover (2002)

N-acyl-L-homoserine lactones (AHLs) are co-regulatory ligands required for control of the expression of genes encoding virulence traits in many Gram-negative bacterial species. Recent studies have indicated that AHLs modulate the cellular concentrations of LuxR-type regulatory proteins by binding and fortifying these proteins against proteolytic degradation (Zhu & Winans, 2001 ). Halogenated furanones produced by the macroalga Delisea pulchra inhibit AHL-dependent gene expression. This study assayed for an in vivo interaction between a tritiated halogenated furanone and the LuxR protein of Vibrio fischeri overproduced in Escherichia coli. Whilst a stable interaction between the algal metabolite and the bacterial protein was not found, it was noted by Western analysis that the half-life of the protein is reduced up to 100-fold in the presence of halogenated furanones. This suggests that halogenated furanones modulate LuxR activity but act to destabilize, rather than protect, the AHL-dependent transcriptional activator. The furanone-dependent reduction in the cellular concentration of the LuxR protein was associated with a reduction in expression of a plasmid encoded P(luxI)-gfp(ASV) fusion suggesting that the reduction in LuxR concentration is the mechanism by which furanones control expression of AHL-dependent phenotypes. The mode of action by which halogenated furanones reduce cellular concentrations of the LuxR protein remains to be characterized.
Alkyl nitrite-metal halide deamination reactions. 2. Substitutive deamination of arylamines by alkyl nitrites and copper(II) halides. A direct and remarkably efficient conversion of arylamines to aryl halides (1977)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAlkyl nitrite-metal halide deamination reactions. 2. Substitutive deamination of arylamines by alkyl nitrites and copper(II) halides. A direct and remarkably efficient conversion of arylamines to aryl halidesMichael P. Doyle, Bernard Siegfried, and Joseph F. Dellaria Jr.Cite this: J. Org. Chem. 1977, 42, 14, 2426–2431Publication Date (Print):July 1, 1977Publication History Published online1 May 2002Published inissue 1 July 1977https://pubs.acs.org/doi/10.1021/jo00434a017https://doi.org/10.1021/jo00434a017research-articleACS PublicationsRequest reuse permissionsArticle Views8613Altmetric-Citations205LEARN 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
Proof verification and the hardness of approximation problems (1998)

We show that every language in NP has a probablistic verifier that checks membership proofs for it using logarithmic number of random bits and by examining a constant number of bits in the proof. If a string is in the language, then there exists a proof such that the verifier accepts with probability 1 (i.e., for every choice of its random string). For strings not in the language, the verifier rejects every provided “proof” with probability at least 1/2. Our result builds upon and improves a recent result of Arora and Safra [1998] whose verifiers examine a nonconstant number of bits in the proof (though this number is a very slowly growing function of the input length). As a consequence, we prove that no MAX SNP-hard problem has a polynomial time approximation scheme, unless NP = P. The class MAX SNP was defined by Papadimitriou and Yannakakis [1991] and hard problems for this class include vertex cover, maximum satisfiability, maximum cut, metric TSP, Steiner trees and shortest superstring. We also improve upon the clique hardness results of Feige et al. [1996] and Arora and Safra [1998] and show that there exists a positive ε such that approximating the maximum clique size in an N -vertex graph to within a factor of N ε is NP-hard.
Cyclic Thrombocytopenia Induced by a Rickettsia-Like Agent in Dogs (1978)

Hematologic manifestations and the ultrastructure of a platelet-specific microorganism isolated from a dog in Florida were studied. The agent was readily transmitted experimentally to adult dogs by intravenous inoculation with infected blood. Parasitemias and concomitant thrombocytopenias were cyclic in that both recurred within relatively constant periods of one to two weeks following experimental infections. Hemorrhage was not a manifestation of the disease even though thrombocytopenias were severe. Microorganisms were visualized by light and electron microscopy. They were observed only in platelets and were composed of single or multiple subunits (morula forms). The microorganisms were ultrastructurally very similar to those reported in Ehrlichia canis infections of dogs and Anaplasma marginale infections of cattle. Microorganisms were surrounded by single membranes which more or less conformed to the external surfaces of subunits that were surrounded by double membranes. From electron microscopic studies, it is suggested that these organisms be classified in the order Rickettsiales.
Construction of 1,2,5‐Tricarbonyl Compounds using Methyl Cyanoacetate as a Glyoxylate Anion Synthon Combined with Copper(I) Iodide‐Catalyzed Aerobic Oxidation (2011)

Abstract A practical and efficient synthesis of various 1,2,5‐tricarbonyl compounds is described. The synthesis has been carried out by a conjugate addition of methyl cyanoacetate to the β‐position of α,β‐unsaturated carbonyl compounds and a subsequent copper(I) iodide‐catalyzed aerobic oxidation. In addition, various α‐aryl‐ and α‐alkyl‐α‐keto esters have been synthesized using a similar approach.
Nanoparticles of Biodegradable Polymers for Clinical Administration of Paclitaxel (2004)

Paclitaxel is one of the best antineoplastic drugs found from nature in the past decades, which has been found effective against a wide spectrum of cancers including ovarian cancer, breast cancer, small and non small cell lung cancer, colon cancer, head and neck cancer, multiple myeloma, melanoma, and Kaposi's sarcoma. Like many other anticancer drugs, it has difficulties in clinical administration due to its poor solubility in water and most pharmaceutical reagents. In its current clinical application, an adjuvant called Cremophor EL has to be employed, which has been found to be responsible for many serious side effects. Nanoparticles of biodegradable polymers can provide an ideal solution to such an adjuvant problem and realize a controlled and targeted delivery of the drug with better efficacy and less side effects. With further development, such as particle size optimization and surface coating, nanoparticle formulation of paclitaxel can promote a new concept of chemotherapy to realize its full efficacy and to improve quality of life of the patients, which includes personalized chemotherapy, local chemotherapy, sustained chemotherapy, oral chemotherapy, chemotherapy across the blood-brain barrier, chemotherapy across the microcirculation barrier, etc. The present research proposes a novel formulation for fabrication of nanoparticles of poly(lactic-co-glycolic acid) (PLGA) by a modified solvent extraction/evaporation technique, in which natural emulsifiers, such as phospholipids, cholesterol and vitamin E TPGS are creatively applied to achieve high drug encapsulation efficiency, desired drug released kinetics, high cell uptake and high cytotoxicity. The nanoparticles composed of various recipes and manufactured under various conditions were characterized by laser light scattering (LLS) for size and size distribution, scanning electron microscopy (SEM) and atomic force microscopy (AFM) for morphological properties, X-ray photoelectron spectroscopy (XPS) and Fourier Transformation Infrared Spectroscopy (FTIR) for surface chemistry, zeta-potential for surface charge, and differential scanning calorimetry (DSC) for the thermogram properties. The drug encapsulation efficiency and the drug release kinetics under in vitro conditions were measured by high performance liquid chromatography (HPLC). It was found that these natural emulsifiers have great advantages for nanoparticle formulation of paclitaxel over the traditional macromolecular emulsifiers, such as polyvinyl alcohol (PVA). Nanoparticles of desired small size and narrow size distribution can be obtained. The drug encapsulation efficiency can be achieved as high as 100 %. The released kinetics can be made under control. The HT-29 cancer cell line experiment showed that after 24 hours of incubation, the cell mortality caused by the drug administered by such nanoparticle formulation could be more than 13 times higher than that caused by the free drug under similar conditions.
Lhx6 Regulates the Migration of Cortical Interneurons from the Ventral Telencephalon But Does Not Specify their GABA Phenotype (2004)

The LIM homeodomain family of transcription factors is involved in many processes in the developing CNS, ranging from cell fate specification to connectivity. A member of this family of transcription factors, lhx6, is expressed in the medial ganglionic eminence (MGE) of the ventral telencephalon, where the vast majority of cortical interneurons are generated. Its expression in the GABA-containing MGE cells that migrate to the cortex suggests that this gene uniquely or in combination with other transcription factors may play a role in the neurochemical identity and migration of these neurons. We performed loss of function studies for lhx6 in mouse embryonic day 13.5 brain slices and dissociated MGE neuronal cultures using Lhx6-targeted small interfering RNA produced by a U6 promoter-driven vector. We found that silencing lhx6 impeded the tangential migration of interneurons into the cortex, although it did not obstruct their dispersion within the ganglionic eminence. Blocking lhx6 expression in dissociated MGE cultured neurons did not interfere with the production of GABA or its synthesizing enzyme. These results indicate that lhx6, unlike the closely related member lhx7, does not regulate neurotransmitter choice in interneurons but plays an important role in their migration from the ventral telencephalon to the neocortex.
Yeast and human genes that affect the Escherichia coli SOS response (1999)

The sequencing of the human genome has led to the identification of many genes whose functions remain to be determined. Because of conservation of genetic function, microbial systems have often been used for identification and characterization of human genes. We have investigated the use of the Escherichia coli SOS induction assay as a screen for yeast and human genes that might play a role in DNA metabolism and/or in genome stability. The SOS system has previously been used to analyze bacterial and viral genes that directly modify DNA. An initial screen of meiotically expressed yeast genes revealed several genes associated with chromosome metabolism (e.g., RAD51 and HHT1 as well as others). The SOS induction assay was then extended to the isolation of human genes. Several known human genes involved in DNA metabolism, such as the Ku70 end-binding protein and DNA ligase IV, were identified, as well as a large number of previously unknown genes. Thus, the SOS assay can be used to identify and characterize human genes, many of which may participate in chromosome metabolism.
Potent aroma compounds in Parmigiano Reggiano cheese studied using a dynamic headspace (purge‐trap) method (2003)

Abstract The aroma‐active compounds potentially important to Parmigiano Reggiano cheese were studied using a dynamic headspace–gas chromatography–olfactometry (GC–O–DH) technique. The aroma contribution was evaluated by both Osme and AEDA technique. The Osme values were based on a 10 point scale, while the ﬂavour dilution values of AEDA were obtained by sequentially reducing the sample size at a ﬁxed purge gas volume. In general, aroma compounds with high Osme values also had high FD values. Among the aroma compounds identiﬁed in Parmigiano Reggiano cheese, acetaldehyde, 2‐methylpropanal, 2‐methylbutanal, 3‐methylbutanal, ethyl butanoate, ethyl hexanoate, ethyl octanoate, methional, dimethyl trisulphide, diacetyl, and 2,6‐dimethylpyrazine were considered the most odour‐potent. Copyright © 2003 John Wiley &amp; Sons, Ltd.
Inhibition of the replication of hepatitis B virus by the carbocyclic analogue of 2'-deoxyguanosine. (1989)

We report that treatment of 2.2.15, a human hepatoblastoma-derived cell line in which hepatitis B virus is actively replicating, with the carbocyclic analogue of 2'-deoxyguanosine [Shealy, Y. F., O'Dell, C. A., Shannon, W. M. & Arnett, G. (1984) J. Med. Chem. 27, 1416-1421] resulted in the nearly complete cessation of viral replication, as monitored by the absence of both intracellular episomal and secreted viral DNAs and by the absence of viral DNA polymerase activity. The drug was nontoxic in concentrations up to 200 times the minimum effective inhibitory concentration.
Amphiphilic proteins from wheat flour : specific extraction, structure and lipid binding properties (1990)

19 ref.
Vaccines: the Fourth Century (2009)

Vaccine development, which began with Edward Jenner's observations in the late 18th century, has entered its 4th century. From its beginnings, with the use of whole organisms that had been weakened or inactivated, to the modern-day use of genetic engineering, it has taken advantage of the tools discovered in other branches of microbiology. Numerous successful vaccines are in use, but the list of diseases for which vaccines do not exist is long. However, the multiplicity of strategies now available, discussed in this article, portends even more successful development of vaccines.
Total synthesis of (.+-.)-dendrobine (1980)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTotal synthesis of (.+-.)-dendrobineWilliam R. RoushCite this: J. Am. Chem. Soc. 1980, 102, 4, 1390–1404Publication Date (Print):February 1, 1980Publication History Published online1 May 2002Published inissue 1 February 1980https://pubs.acs.org/doi/10.1021/ja00524a027https://doi.org/10.1021/ja00524a027research-articleACS PublicationsRequest reuse permissionsArticle Views2638Altmetric-Citations94LEARN 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
HLA-DR Expression and Soluble HLA-DR Levels in Septic Patients After Trauma (1999)

In severely injured patients, decreased levels of cellular and soluble HLA-DR appear as early indicators of an immune deviation associated with the development of severe sepsis. Moreover, immune alterations of different cell types may promote distinct kinds of septicemia.
Propagation and Maintenance of Undifferentiated Human Embryonic Stem Cells (2004)

Human embryonic stem (hES) cells, like other stem cells, have the capacity to self-renew without differentiation. Although hES cells can be differentiated to many different tissue types in vitro, clinical uses have not yet been realized from the study of hES cells. Anticipation that these cells would be immediately useful for creating models of human disease has not yet been fulfilled. However, because of their self-renewing and pluripotential nature, hES cells indeed hold unique promise for many areas of research and medicine. A major problem complicating developments in hES cell research is the difficulty of propagating and maintaining these cells in vitro without differentiation. This review addresses this problem and potential solutions in detail. In addition, the current state of research regarding the growth and maintenance of hES cells is summarized, along with basic protocols utilized by our laboratory for the successful propagation, characterization, and investigation of hES cells.
Electric Field Induced Orientation of Polymer Chains in Macroscopically Aligned Electrospun Polymer Nanofibers (2007)

The results presented in this work show for the first time that an electric field used to macroscopically align polymer nanofibers can also align polymer chains parallel to the fiber axis. This important result indicates that anisotropic structural properties (mechanical, electrical, etc.) can be induced in polymer nanofibers during the electrospinning process. Such uniaxially oriented nanofibers exhibit a variety of potential applications in biomedicine, microelectronics, and optics. A simple technique of vertical electrospinning with an electric field induced, stationary collection was employed to obtain the molecular orientation in polymer nanofibers. This manuscript describes the orientation process via electrospinning and verifies this molecular orientation in the polymer nanofibers using three independent methods: polarized Fourier transform infrared spectroscopy, polarized Raman scattering, and X-ray diffraction.
Reduced Expression of the let-7 MicroRNAs in Human Lung Cancers in Association with Shortened Postoperative Survival (2004)

In this study, we report for the first time reduced expression of the let-7 microRNA in human lung cancers. Interestingly, 143 lung cancer cases that had undergone potentially curative resection could be classified into two major groups according to let-7 expression in unsupervised hierarchical analysis, showing significantly shorter survival after potentially curative resection in cases with reduced let-7 expression (P = 0.0003). Multivariate COX regression analysis showed this prognostic impact to be independent of disease stage (hazard ratio = 2.17; P = 0.009). In addition, overexpression of let-7 in A549 lung adenocarcinoma cell line inhibited lung cancer cell growth in vitro. This study represents the first report of reduced expression of let-7 and the potential clinical and biological effects of such a microRNA alteration.
Camera calibration for lane and obstacle detection (2003)

This paper deals with camera calibration for use in guided vehicles. Camera calibration yields parameters which describe the relationship between 2D images and 3D environment. An intrinsic camera calibration is performed and the extrinsic parameters are determined using a weighted least squares technique within a robust, iterative estimator. They allow a correct 3D reconstruction from the given images. This information is indispensable for lane and obstacle detection with the goal of driving an autonomous, unsupervised vehicle. The impacts of uncertainty in the calibration parameters on lane recognition and obstacle detection are quantified. It is shown that reliable results of lane recognition and object detection can only be performed with calibration parameters of high precision.
Cubic Mesoporous Silica with Large Controllable Entrance Sizes and Advanced Adsorption Properties (2003)

Large cavities (≈10–12.3 nm) of cubic (Fm-3m) mesoporous silica without intergrowth are synthesized in the presence of block copolymer templates. The entrance sizes of these cavities can be adjusted in the range of ≈4–9 nm as confirmed by nitrogen sorption studies and an examination of the negative gold replicas. The 3D open mesostructures facilitate the transportation of biomolecules (see picture), as well as the replication of a large-pore (9 nm) cubic mesoporous carbon. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2003/z51027_s.pdf or from the author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.