gebhart/patrepeval huggingface dataset:
Role of the Nozaki–Hiyama–Takai–Kishi Reaction in the Synthesis of Natural Products (2017)

The Nozaki-Hiyama-Takai-Kishi (NHTK) reaction was discovered in the late 1970s and, since then, its main application has been its use in total synthesis. In this comprehensive review, the efficiency of the NHKT reaction in the synthesis of a great number of different scaffolds present in complex natural products is analyzed. The preparation of enol and allylic and propargylic alcohol motifs is discussed, highlighting factors such as yield, chemoselectivity, stereoselectivity, or the importance of protecting groups. The review is divided into two main sections: intermolecular and intramolecular NHTK reactions. A final discussion about the current "state-of-art" and future perspectives for the use of this transformation in total synthesis is also included.
ChemInform Abstract: Acyloin Condensation of 1,2‐Diacyloxyethanes: Directed Synthesis of Unsymmetrically Substituted 1,2‐Bis‐(trimethylsiloxy)ethenes. (1995)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Performance analysis of the out-of-band signaling scheme for high speed wireless LANs (2005)

In this paper, we study the performance of our earlier proposed out-of-band signaling (OBS) scheme for high speed wireless local area networks (WLANs). We employ the system approximation technique for modeling of the OBS scheme. An equivalent state dependent single server queue, that describes the OBS scheme, is constructed for the analysis of the throughput and delay performances. Moreover, we study the throughput optimization of the OBS scheme, which provides a means for optimizing the performance of the OBS scheme, given a particular network environment. Finally, we conduct several simulation experiments to validate our analytical results.
Plasticizers from Tetrahydrofurfurly Alcohol. (1960)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPlasticizers from Tetrahydrofurfurly Alcohol.L. H. Brown and J. W. HillCite this: J. Chem. Eng. Data 1960, 5, 1, 56–58Publication Date (Print):January 1, 1960Publication History Published online1 May 2002Published inissue 1 January 1960https://pubs.acs.org/doi/10.1021/je60005a015https://doi.org/10.1021/je60005a015research-articleACS PublicationsRequest reuse permissionsArticle Views81Altmetric-Citations2LEARN 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
A quick address detection of an anomalous memory cell for flash EEPROM (2002)

A simple technique for quickly detecting an address of an anomalous memory cell for flash EEPROM devices is described. A proposed Multi-Address Selection Scheme (MASS) can drastically reduce measurement cycles for searching an address of an anomalous memory cell which has an abnormally high or low threshold voltage. A systematic evaluation for the reliability of flash EEPROM has been realized by this quick address detection technology.
Mutants affecting processing of DNA in macronuclear development in paramecium. (1991)

In Paramecium tetraurelia, stock 51, the A surface protein is coded by the wild type A51 gene, present in micronuclei in two copies and in macronuclei in about 1500 copies. DNA processing, comprised of DNA cleavage, copy number amplification and telomere addition occurs at autogamy and conjugation when old macronuclei degrade and new macronuclei are formed from micronuclei. In this paper we characterize mutants with macronuclear A gene deletions. These mutants are notable in three respects. First, the mutants do not appear to be simple micronuclear deletions. Although genetic analysis shows that the d12 mutant d12(-1300) is homozygous for the allele A-1300 and the mutant d12(+1) for A+1, analysis by the polymerase chain reaction indicates that the micronuclei in these two mutants contain intact, but presumably altered, micronuclear A genes. They undergo deletion during DNA processing when new macronuclei are formed. Second, the position of the deletions in these alleles has been shown to change. The deficiency present in the d12 allele A-1300 was originally determined to extend from position -1300 (relative to the start of translation of the A gene) to the end of the chromosome. Later, a derivative of this strain, homozygous for the d12 allele A+1 was isolated in which the start site of the deletion was found to have moved from -1300 to +1. Third, a surprising interaction occurs in crosses between a line homozygous for the d12 allele and one homozygous for the wild-type A51 allele. Previous work on the non-Mendelian d48 mutant (which has intact A51 genes in its micronucleus, but has truncated A51 genes in its macronucleus) has shown that intact A51 alleles must be present in the old macronucleus in order for A51 alleles to undergo proper processing. We find that d12 alleles act on A51 alleles in heterozygotes such that intact macronuclear A genes are no longer required for proper processing of A51. Thus, in crosses of 51 x d12 (either +1 or -1300) d12 exconjugants, as well as 51 exconjugants, give rise to clones carrying both intact A51 and truncated d12 alleles. Remarkably the d12 alleles, which are themselves deleted during processing, are capable in the heterozygote of fostering normal processing of the A51 allele.
Identification of the Kappa-Opioid Receptor as a Therapeutic Target for Oligodendrocyte Remyelination (2016)

Remyelination represents a promising strategy to achieve functional recovery in demyelinating diseases, like MS. Thus, identification of potent compounds and targets that promote remyelination represents a critically unmet need. This study reports a cluster of compounds that are highly effective in enhancing remyelination and identifies κ-opioid receptor (KOR) as a positive regulator for oligodendroglial differentiation, implicating KOR agonism as a potential strategy to accelerate remyelination.
Robust Autofocusing Approach for Highly Squinted SAR Imagery Using the Extended Wavenumber Algorithm (2013)

For highly squinted synthetic aperture radar (SAR) imaging, the wavenumber domain SAR processing algorithm is commonly accepted as an ideal solution to SAR focusing in the case of an ideal straight sensor trajectory. However, airborne SAR is very sensitive to atmospheric turbulence that causes serious trajectory deviations. In this paper, we propose a robust autofocusing approach for highly squinted airborne SAR imagery using the extended wavenumber algorithm, being capable of estimating the range-dependent phase errors. To apply the proposed autofocusing scheme, a detailed analysis of the motion error model in the conical reference system is presented, where the formulation of range-dependent phase errors for squinted SAR is given. The proposed autofocusing approach is performed by a three-step process: referring to the inevitable residual phase after deramping for highly squinted SAR, a modified squinted phase gradient autofocusing (SPGA) algorithm is put forward to retrieve the range-independent phase errors; based on the established motion error model, the residual range-dependent phase errors are estimated using a local maximum likelihood-weighted SPGA algorithm; and motion compensation is executed by a two-step approach to reach the range-independent and range-dependent corrections, respectively. Experiments based on measured data have shown that the proposed autofocusing approach performs well for highly squinted SAR imaging.
On Polynomial Kernelization of $\mathcal{H}$-free Edge Deletion (2014)

For a set of graphs $\mathcal{H}$, the \textsc{$\mathcal{H}$-free Edge Deletion} problem asks to find whether there exist at most $k$ edges in the input graph whose deletion results in a graph without any induced copy of $H\in\mathcal{H}$. In \cite{cai1996fixed}, it is shown that the problem is fixed-parameter tractable if $\mathcal{H}$ is of finite cardinality. However, it is proved in \cite{cai2013incompressibility} that if $\mathcal{H}$ is a singleton set containing $H$, for a large class of $H$, there exists no polynomial kernel unless $coNP\subseteq NP/poly$. In this paper, we present a polynomial kernel for this problem for any fixed finite set $\mathcal{H}$ of connected graphs and when the input graphs are of bounded degree. We note that there are \textsc{$\mathcal{H}$-free Edge Deletion} problems which remain NP-complete even for the bounded degree input graphs, for example \textsc{Triangle-free Edge Deletion}\cite{brugmann2009generating} and \textsc{Custer Edge Deletion($P_3$-free Edge Deletion)}\cite{komusiewicz2011alternative}. When $\mathcal{H}$ contains $K_{1,s}$, we obtain a stronger result - a polynomial kernel for $K_t$-free input graphs (for any fixed $t&gt; 2$). We note that for $s&gt;9$, there is an incompressibility result for \textsc{$K_{1,s}$-free Edge Deletion} for general graphs \cite{cai2012polynomial}. Our result provides first polynomial kernels for \textsc{Claw-free Edge Deletion} and \textsc{Line Edge Deletion} for $K_t$-free input graphs which are NP-complete even for $K_4$-free graphs\cite{yannakakis1981edge} and were raised as open problems in \cite{cai2013incompressibility,open2013worker}.
Evaluation of some new condensing reagents for hydrogenphosphonate diester formation. (1987)

Various pivaloyltetrazoles and chlorophosphates have been investigated as potential condensing reagents for H-phosphonate diester formation. Acylating or phosphorylating properties as well as possible side-reactions triggered by these reagents were checked using TLC and 31P NMR analysis.
Regulated Expression of the Beta2-Toxin Gene ( cpb2 ) in Clostridium perfringens Type A Isolates from Horses with Gastrointestinal Diseases (2005)

Recent epidemiological studies suggested that cpb2-positive Clostridium perfringens isolates are associated with gastrointestinal (GI) diseases in horses. These putative relationships, indicated by PCR genotyping, were tested in the present study by further genotyping and phenotyping of 23 cpb2-positive C. perfringens isolates from horses with GI disease (referred to hereafter as horse GI disease isolates). Our beta2-toxin (CPB2) Western blot analyses demonstrated that all of the tested isolates were unable to produce detectable levels of CPB2. However, Southern blot and nucleotide sequencing analyses identified intact cpb2 open reading frames in all of our surveyed horse GI disease isolates. Furthermore, reverse transcriptase PCR and Northern blot analyses showed that cpb2 genes in all of our surveyed horse GI disease isolates were transcriptionally active, i.e., an approximately 1.2-kb cpb2-specific mRNA was identified in total RNA from our surveyed isolates. The levels of cpb2 mRNA in CWC245 (a high-CPB2-producing pig strain) and our surveyed horse GI disease isolates differed to such an extent (35-fold) that this difference could be considered as a major cause of the difference in levels of CPB2 production by CWC245 and horse GI disease isolates. This finding received further support from our observation that the complementing strain 106902(pMRS140), which produced significantly higher levels of mRNA than strain 106902, produced high levels of CPB2. Collectively, our results indicated that there is a positive correlation between cpb2 transcription levels and the amount of CPB2 produced by a C. perfringens cell and that decreased transcription and/or message instability may be involved, at least in part, in the low CPB2 production noted for horse GI disease isolates in comparison to that noted for pig GI disease isolate CWC245.
Engineering Prototype for a Compact Medical Dielectric Wall Accelerator (2011)

Abstract not provided
Unified Green’s Function Retrieval by Cross Correlation (2006)

It has been shown by many authors that the cross correlation of two recordings of a diffuse wave field at different receivers yields the Green's function between these receivers. Recently the theory has been extended for situations where time-reversal invariance does not hold (e.g., in attenuating media) and where source-receiver reciprocity breaks down (in moving fluids). Here we present a unified theory for Green's function retrieval that captures all these situations and, because of the unified form, readily extends to more complex situations, such as electrokinetic Green's function retrieval in poroelastic or piezoelectric media. The unified theory has a wide range of applications in "remote sensing without a source."
Capturing skin properties from dynamic mechanical analyses (2012)

The high reliability and speed of measurement make this device and analytic procedure an attractive option for testing skin mechanics.
Inhibition by Dexamethasone of the in Vivo Pituitary Response to Corticotropin-Releasing Factor (CRF)1 (1969)

Dexamethasone phosphate in doses ranging from 0 (vehicle control) to 2 μg/rat was injected into both lobes of the anterior pituitary, or into the median eminence or septa region of the brain. Endogenous CRF release was provoked by scald. Dexamethasone bilaterally in the anterior pituitary inhibited ACTH release after scald in doses of 100 ng/lobe or greater. These doses of dexamethasone were ineffective against scald when given intravenously. These results indicated that endogenous CRF-induced ACTH secretion is a corticosteroid-sensitive process, and that the anterior pituitary may be a corticosteroid feedback point. To test this conclusion further, we studied the effect of intrapituitary dexamethasone on the ACTH release induced by exogenous ovine CRF. Intrapituitary dexamethasone was again effective in preventing ACTH release. When similar small doses of dexamethasone were placed in the anterior medial basal hypothalamus, they were effective in stopping the adrenocortical response both to scald and to exogenous CRF. Apparently, spread of dexamethasone from the median eminence to the anterior pituitary can be extensive and rapid. Furthermore, dexamethasone placed in the septal region of the brain, distant from the medial basal hypothalamus, also prevented ACTH release following exogenous CRF. By means of a fluorescent dye, we found that very rapid spread of injected materials to the pituitary occurs after hypothalamic or septal region injections. Though our results may challenge some previous experiments purporting to show the existence of corticosteroid feedback sites in the brain, they do not exclude that possibility. They do establish that the ACTH-releasing process of the pituitary can be inhibited locally by dexamethasone, and therefore that the anterior pituitary may be a corticosteroid inhibitory feedback site. (Endocrinology85: 512, 1969)
Monitoring of fatigue damage in composite lap-joints using guided waves and FBG sensors (2016)

Adhesive bonding is being increasingly employed in many applications as it offers possibility of light-weighting and efficient multi-material joining along with reduction in time and cost of manufacturing. However, failure initiation and progression in critical components like joints, specifically in fatigue loading is not well understood, which necessitates reliable NDE and SHM techniques to ensure structural integrity. In this work, concurrent guided wave (GW) and fiber Bragg grating (FBG) sensor measurements were used to monitor fatigue damage in adhesively bonded composite lap-joints. In the present set-up, one FBG sensor was strategically embedded in the adhesive bond-line of a lap-joint, while two other FBGs were bonded on the surface of the adherends. Full spectral responses of FBG sensors were collected and compared at specific intervals of fatigue loading. In parallel, guided waves were actuated and sensed using PZT wafers mounted on the composite adherends. Experimental results demonstrated that time-of-flight (ToF) of the fundamental modes transmitted through the bond-line and spectral response of FBG sensors were sensitive to fatigue loading and damage. Combination of guided wave and FBG measurements provided the desired redundancy and synergy in the data to evaluate the degradation in bond-line properties. Measurements taken in the presence of continuously applied load replicated the in-situ/service conditions. The approach shows promise in understanding the behavior of bonded joints subjected to complex loading.
A perceptual assistant to do sound equalization (2000)

This paper describes an intelligent interface to assist in the expert perceptual task of sound equalization. This is commonly done by a sound engineer in a recording studio, live concert setting, or in setting up audio systems. The system uses inductive learning to acquire expert skill using nearest neighbor pattern recognition. This skill is then used in a sound equalization expert system, which learns to proficiently adjust the timbres (tonal qualities) of brightness, darkness, and smoothness in a context-dependent fashion. The computer is used as a tool to sense, process, and act in helping the user perform a perceptual task. Adjusting timbres of sound is complicated by the fact that there are non-linear relationships between equalization adjustments and perceived sound quality changes. The developed system shows that the nearest-neighbor context-dependent equalization is rated 68% higher than the set linear average equalization and that it is preferred 81% of the time.
Controlled-Force Grinding—A New Technique for Precision Internal Grinding (1964)

The causes of random-size variations and random-taper variations in feed-rate grinding are described and related to stock variations and wheel-sharpness variations. A new technique, controlled-force grinding, is presented which eliminates errors resulting from variable elastic deflections. An analysis is made of the rounding-up dynamics of the controlled-force system and a critical workspeed is found which must be exceeded in order to have a rounding-up action. A study is also made of the stability of the system using the Nyquist criterion.
Near-Infrared Spectrometry of Microorganisms in Liquid Pharmaceuticals (1990)

Biotechnology and pharmaceutical research have created a number of new and potentially life-saving drugs. Many of these drugs are formulated as injectable products. Some drug products do not survive autoclaving or other means of terminal sterilization. An aseptic filling process is typically used to sterilize such products, but it is less reliable than autoclaving, making detection of unsterile units even more essential. Invasive microbiological methods and turbidimetry are currently employed as inspection techniques. These processes are time-consuming, destroy product, and may not detect low levels of contamination. Near-IR light scattering is proposed as a new method of determining low levels of contamination noninvasively and nondestructively. The method is used successfully in the current study to detect contamination by a species of yeast, mold, and bacteria in intact plastic infusion bags at levels as low as three colony-forming units per milliliter for yeast. By use of the near-IR method, each injectable unit can be evaluated with its integrity maintained, allowing the product to be dispensed or evaluated by another analytical method.
LTL Control in Uncertain Environments with Probabilistic Satisfaction\n Guarantees (2011)

We present a method to generate a robot control strategy that maximizes the\nprobability to accomplish a task. The task is given as a Linear Temporal Logic\n(LTL) formula over a set of properties that can be satisfied at the regions of\na partitioned environment. We assume that the probabilities with which the\nproperties are satisfied at the regions are known, and the robot can determine\nthe truth value of a proposition only at the current region. Motivated by\nseveral results on partitioned-based abstractions, we assume that the motion is\nperformed on a graph. To account for noisy sensors and actuators, we assume\nthat a control action enables several transitions with known probabilities. We\nshow that this problem can be reduced to the problem of generating a control\npolicy for a Markov Decision Process (MDP) such that the probability of\nsatisfying an LTL formula over its states is maximized. We provide a complete\nsolution for the latter problem that builds on existing results from\nprobabilistic model checking. We include an illustrative case study.\n
Automating the construction of scene classifiers for content-based video retrieval (2004)

This paper introduces a real time automatic scene classifier within content-based video retrieval. In our envisioned approach end users like documentalists, not image processing experts, build classifiers interactively, by simply indicating positive examples of a scene. Classification consists of a two stage procedure. First, small image fragments called patches are classified. Second, frequency vectors of these patch classifications are fed into a second classifier for global scene classification (e.g., city, portraits, or countryside). The first stage classifiers can be seen as a set of highly specialized, learned feature detectors, as an alternative to letting an image processing expert determine features a priori. We present results for experiments on a variety of patch and image classes. The scene classifier has been used successfully within television archives and for Internet porn filtering.
Efficient Post-Compression Error-Resilient 3D-Scalable Video Transmission for Packet Erasure Channels (2006)

We propose an efficient error-resilient video transmission algorithm over packet erasure channels using optimal source and channel bit-allocation. This algorithm uses FEC and rate-distortion optimization to find the optimal allocation of source and channel bits in each quality layer. The packet loss probability is periodically reported to the video server. This method can also be incorporated with any coding structure that generates a set of independent compressed bitstreams. The algorithm efficacy is demonstrated by simulations in which the video compression is an error-resilient 3D-SPIHT algorithm and the channel protection is provided by Reed-Solomon (RS) codes.
ChemInform Abstract: A Highly Recyclable Magnetic Core‐Shell Nanoparticle‐Supported TEMPO Catalyst for Efficient Metal‐ and Halogen‐Free Aerobic Oxidation of Alcohols in Water. (2011)

Abstract The highly efficient heterogeneous catalyst is used for the aerobic oxidation of primary, secondary, allylic, and even sterically hindered alcohols in water.
RETRACTED ARTICLE: Chronic NMDA administration to rats increases brain pro-apoptotic factors while decreasing anti-Apoptotic factors and causes cell death (2009)

This alteration in the balance between pro- and anti-apoptotic factors by chronic NMDA receptor activation in this animal model may contribute to neuronal loss, and further suggests that the model can be used to examine multiple processes involved in excitotoxicity.