gebhart/patrepeval huggingface dataset:
Optimization of heat engines including the saving of natural resources and the reduction of thermal pollution (2000)

The use of the new concept of a saving functionas a measure of possible reductions of undesired side effects in heat engine operation is proposed. Two saving functions are introduced, one associated with fuel consumption and another associated with thermal pollution. Two optimization paths including the maximization of power output and these saving functions are presented. The first is based on a linear formalism and the second is based on a power-law formalism. When these optimization criteria are applied to a Curzon-Ahlborn heat engine, both criteria lead to a very similar optimum efficiency, opt = 1- 3/4 , where is the ratio between the temperatures of the cold and the hot external reservoirs. A numerical comparison with the efficiency of some modern nuclear power plants is reported.
42% high efficiency two-stage HBT power amplifier MMIC for W-CDMA cellular phone system (2002)

This paper is the first to report a high efficiency two-stage HBT power amplifier MMIC for 1.95 GHz wide-band CDMA (W-CDMA) cellular phone system. Power amplifiers for W-CDMA system are required with high efficiency and high linearity over a wide range of output power level. To obtain a high efficiency, we chose a near class B operation. To obtain a high linearity, we suppressed the gain distortion due to a near class B operation by the adaptive biasing technique. The MMIC exhibited the highest power-added efficiency (PAE) of 42% ever reported, a gain of 30.5 dB, and an adjacent channel leakage power ratio (ACLR) it a 5 MHz offset frequency of -38 dBc at a Pout of 27 dBm under a supply voltage of 3.5 V with 3.84 Mcps HPSK modulation.
The ectonucleotidases <scp>CD</scp>39 and <scp>CD</scp>73: Novel checkpoint inhibitor targets (2017)

Cancers are able to grow by subverting immune suppressive pathways, to prevent the malignant cells as being recognized as dangerous or foreign. This mechanism prevents the cancer from being eliminated by the immune system and allows disease to progress from a very early stage to a lethal state. Immunotherapies are newly developing interventions that modify the patient's immune system to fight cancer, by either directly stimulating rejection-type processes or blocking suppressive pathways. Extracellular adenosine generated by the ectonucleotidases CD39 and CD73 is a newly recognized "immune checkpoint mediator" that interferes with anti-tumor immune responses. In this review, we focus on CD39 and CD73 ectoenzymes and encompass aspects of the biochemistry of these molecules as well as detailing the distribution and function on immune cells. Effects of CD39 and CD73 inhibition in preclinical and clinical studies are discussed. Finally, we provide insights into potential clinical application of adenosinergic and other purinergic-targeting therapies and forecast how these might develop in combination with other anti-cancer modalities.
Histological Reaction to Polyimide Films in the Cochlea (1989)

The biocompatibility of commercially available polyimides was examined in relation to the sensory and neural structures of the cochlea. Thin films of four different polyimides were prepared as substrates for photolithographically produced scala tympani electrode arrays and implanted in 32 cat cochleae. Following at least three months implantation time, the animals were sacrificed and the cochlea were evaluated histologically for toxicity, differences in the severity of ototoxic effects among the four polyimide groups, and relationships among the different kinds of histopathology secondary to implantation. Findings included the following. Inflammatory reaction to the implants, when present, was generally mild and confined to the immediate vicinity of the implant. Additionally, ototoxic effects were essentially the same across the four groups. Finally, a clear interdependence among the different kinds of cochlear damage secondary to implantation was demonstrated.
A high precision ultrasonic system for vibration measurements (1992)

A microcomputer-aided ultrasonic system that can be used to measure the vibratory displacements of an object is presented. A pair of low cost 40-kHz ultrasonic transducers is used to transmit ultrasound toward an object and receive the ultrasound reflected from the object. The relative motion of the object modulates the phase angle difference between the transmitted and received ultrasound signals. A single-chip microcomputer-based phase detector was designed to record and analyze the phase shift information which is then sent to a PC-AT microcomputer for processing. We have developed an ingenious method to reconstruct the relative motion of an object from the acquired data of the phase difference changes. A digital plotter based experiment was also designed for testing the performance of the whole system. The measured accuracy of the system in the reported experiments is within ±0.4 mm and the theoretical maximal measurable speed of the object is 89.6 cm/s. The main advantages of this ultrasonic vibration measurement system are high resolution, low cost, noncontact measurement and it is easily installed.
Degradation of Rod Outer Segment Proteins by Cathepsin D (1975)

The degradation of proteins of the rod outer segment (ROS) fraction by partially purified cathepsin D [EC 3.4.23.5] from the retinal pigment epithelium was studied. The ROS fraction, prepared from bovine eyes by sucrose density gradient centrifugation, had little cathepsin D activity. Partially purified cathepsin D, obtained from crude extract of bovine retinal pigment epithelium using bovine serum albumin as a substrate, hydrolyzed the porteine of the ROS fraction. The rate of degradation of ROS proteins was proportional to both the enzyme concentration and the incubation time. With ROS proteins as substrate, the optimal pH of cathepsin D was about 3.5. The degradation of ROS proteins was inhibited by pepstatin.
Sensitivity to tilt in first-order and second-order gratings is immature in 5-year-olds (2010)

We measured orientation discrimination in 24 5-year-olds (± 3 months) and 24 adults (18 – 25 years of age) for first-order (luminance-modulated) and second-order (contrast-modulated) gratings. To achieve equal visibility, contrast for each age and condition was set at a fixed multiple of threshold contrast for discriminating horizontal from vertical gratings. For the test of sensitivity to orientation, the subject's task on each trial was to indicate whether the stripes were tilted to the left or right of vertical. Tilt was varied over trials according to a ML-TEST staircase procedure (Harvey, 1986) to measure the minimum tilt that could be discriminated from vertical 82% of the time. An ANOVA showed that tilt discrimination was immature in 5-year-olds (main effect of age, p p > 0.20). Specifically, the minimum discriminable tilt was 4 – 5 times worse in 5-year-olds than adults for both first-order patterns (adult mean = 0.9°; 5-year-old mean = 4.4°) and for second-order patterns (adult mean = 1.4°; 5-year-old mean = 5.5°). These immaturities are unlikely to be caused by motivational or attentional factors because 5-year-olds have nearly adult-like values for other thresholds measured with similar methods (Ellemberg et al., 2003). Thus, the neural mechanisms mediating orientation discrimination appear not to become adult-like until some time after 5 years of age. Moreover, thresholds at both ages were significantly worse (1.2 – 1.5 times worse) for second-order modulation than for first-order modulation (main effect of stimulus type, p < 0.01). This difference provides further support for the hypothesis (e.g., Chubb & Sperling, 1988) that the processing of first- and second-order information is mediated, at least in part, by separate mechanisms.
Flexible Phototransistors Based on Single‐Crystalline Silicon Nanomembranes (2015)

In this work, flexible phototransistors with a back gate configuration based on transferrable single‐crystalline Si nanomembrane (Si NM) have been demonstrated. Having the Si NM as the top layer enables full exposure of the active region to an incident light and thus allows for effective light sensing. Flexible phototransistors are performed in two operation modes: 1) the high light detection mode that exhibits a photo‐to‐dark current ratio of 10 5 at voltage bias of V GS < 0.5 V, and V DS = 50 mV and 2) the high responsivity mode that shows a maximum responsivity of 52 A W −1 under blue illumination at voltage bias of V GS = 1 V, and V DS = 3 V. Due to the good mechanical flexibility of Si NMs with the assistance of a polymer layer to enhance light absorption, the device exhibits stable responsivity with less than 5% of variation under bending at small radii of curvatures (up to 15 mm). Overall, such flexible phototransistors with the capabilities of high sensitivity light detection and stable performance under the bending conditions offer great promises for high‐performance flexible optical sensor applications, with easy integration for multifunctional applications.
Cerebrovascular Effects of Carbon Monoxide (2002)

This review examines the influence of endogenous and exogenous carbon monoxide (CO) on the cerebral circulation. Although CO generated from neuronal heme oxygenase can modulate neurotransmission, evidence supporting its role in cerebral vasodilation is limited. In newborn piglets, heme oxygenase is enriched in microvessels and contributes to hypoxic vasodilation. Low CO concentrations dilate piglet arterioles by opening calcium-activated potassium channels. With inhalation of CO and formation of carboxyhemoglobin, cerebral vasodilation can be greater than that occurring with hypoxic hypoxia at equivalent reductions of arterial oxygen content. This additional vasodilation is probably attributable to additional release of hypoxic vasodilators secondary to increased oxyhemoglobin affinity, although direct effects of CO on cerebral arterioles may also occur. When CO exposure is prolonged, cerebral endothelium undergoes oxidant stress as evident by nitrotyrosine formation. As CO levels increase, modest decreases in oxygen consumption are detectable, which may reflect CO or nitric oxide interactions with cytochrome oxidase in regions with very low oxygen availability. If subsequent CO concentration increases sufficiently to depress cardiac function and limit cerebral perfusion, cerebral oxygen consumption becomes further reduced, and oxidant stress becomes amplified by leukocyte sequestration and xanthine oxidase activity with consequent lipid peroxidation. Specific regions of the brain, such as central white matter, globus pallidus, and hippocampus, are selectively vulnerable to CO toxicity, but whether the mechanisms involved in selective injury differ from other forms of hypoxia-ischemia needs to be clarified.
Stable Protein Device Platform Based on Pyridine Dicarboxylic Acid-Bound Cubic-Nanostructured Mesoporous Titania Films (2013)

Here we shortly report a protein device platform that is extremely stable in a buffer condition similar to human bodies. The protein device platform was fabricated by covalently attaching cytochrome c (cyt c) protein molecules to organic coupler molecules (pyridine dicarboxylic acid, PDA) that were already covalently bound to an electron-transporting substrate. A cubic nanostructured mesoporous titania film was chosen as an electron-transporting substrate because of its large-sized cubic holes (∼7 nm) and highly crystalline cubic titania walls (∼0.4 nm lattice). Binding of PDA molecules to the mesoporous titania surface was achieved by esterification reaction between carboxylic acid groups (PDA) and hydroxyl groups (titania) in the presence of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) mediator, whereas the immobilization of cyt c to the PDA coupler was carried out by the EDC-mediated amidation reaction between carboxylic acid groups (PDA) and amine groups (cyt c). Results showed that the 2,4-position isomer among several PDAs exhibited the highest oxidation and reduction peak currents. The cyt c-immobilized PDA-bound titania substrates showed stable and durable electrochemical performances upon continuous current-voltage cycling for 240 times (the final current change was less than 3%) and could detect superoxide that is a core indicator for various diseases including cancers.
C-Terminal cysteines of Tn501 mercuric ion reductase (1992)

Mercuric ion reductase (MerA) catalyzes the reduction of Hg(II) to Hg(0) as the last step in the bacterial mercury detoxification pathway. A member of the flavin disulfide oxidoreductase family, MerA contains an FAD prosthetic group and redox-active disulfide in its active site. However, the presence of these two moieties is not sufficient for catalytic Hg(II) reduction, as other enzyme family members are potently inhibited by mercurials. We have previously identified a second pair of active site cysteines (Cys558 Cys559 in the Tn501 enzyme) unique to MerA, that are essential for high levels of mercuric ion reductase activity [Moore, M. J., & Walsh, C. T. (1989) Biochemistry 28, 1183; Miller, S. M., et al. (1989) Biochemistry 28, 1194]. In this paper, we have examined the individual roles of Cys558 and Cys559 by site-directed mutagenesis of each to alanine. Phenotypic analysis indicates that both merA mutations result in a total disruption of the Hg(II) detoxification pathway in vivo, while characterization of the purified mutant enzymes in vitro shows each to have differential effects on catalytic function. Compared to wild-type enzyme, the C558A mutant shows a 20-fold reduction in kcat and a 10-fold increase in Km, for an overall decrease in catalytic efficiency of 200-fold in kcat/Km. In contrast, mutation of Cys559 to alanine results in less than a 2-fold reduction in kcat and an increase in Km of only 4-5 fold for an overall decrease in catalytic efficiency of only ca. 10-fold in vitro. From these results, it appears that Cys558 plays a more important role in forming the reducible complex with Hg(II), while both Cys558 and Cys559 seem to be involved in efficient scavenging (i.e., tight binding) of Hg(II).
Epoxidation of Olefins Using Methyl(trifluoromethyl)dioxirane Generated in Situ (1995)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEpoxidation of Olefins Using Methyl(trifluoromethyl)dioxirane Generated in SituDan Yang, Man-Kin Wong, and Yiu-Chung YipCite this: J. Org. Chem. 1995, 60, 12, 3887–3889Publication Date (Print):June 1, 1995Publication History Published online1 May 2002Published inissue 1 June 1995https://pubs.acs.org/doi/10.1021/jo00117a046https://doi.org/10.1021/jo00117a046research-articleACS PublicationsRequest reuse permissionsArticle Views4038Altmetric-Citations232LEARN 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
Clinical Characteristics of Patients with Autoimmune Pancreatitis with or without Mikulicz's Disease and Mikulicz's Disease Alone (2013)

The relapse rate of AIP in MD patients was significantly higher than that of AIP in patients without MD.
Oncogenic Mechanisms of Histone H3 Mutations (2016)

Recurrent missense mutations in histone H3 were recently reported in pediatric gliomas and soft tissue tumors. Strikingly, these mutations only affected a minority of the total cellular H3 proteins and occurred at or near lysine residues at positions 27 and 36 on the amino-terminal tail of H3 that are subject to well-characterized posttranslational modifications. Here we review recent progress in elucidating the mechanisms by which these mutations perturb the chromatin landscape in cells through their effects on chromatin-modifying machinery, particularly through inhibition of specific histone lysine methyltransferases. One common feature of histone mutations is their ability to arrest cells in a primitive state refractory to differentiation induction, highlighting the importance of studying these mutations in their proper developmental context.
Wnt/Beta-Catenin/Tcf Signaling: A Critical Pathway in Gastrointestinal Tumorigenesis (2002)

Cancers of the gastrointestinal tract, including the liver, bile ducts, and pancreas, constitute the largest group of malignant tumors. Colorectal cancer is one of the most common neoplastic diseases in Western countries and one of the leading causes of cancer-related deaths. Inactivation of the adenomatous polyposis coli (APC) tumor-suppressor gene during early adenoma formation is thought to be the first genetic event in the process of colorectal carcinogenesis followed by mutations in oncogenes like K-Ras and tumor-suppressor genes like p53. Identification of the interaction of APC with the proto-oncogene beta-catenin has linked colorectal carcinogenesis to the Wnt-signal transduction pathway. The main function of APC is thought to be the regulation of free beta-catenin in concert with the glycogen synthase kinase 3beta (GSK-3beta) and Axin proteins. Loss of APC function, inactivation of Axin or activating beta-catenin mutations result in the cellular accumulation of beta-catenin. Upon translocation to the nucleus beta-catenin serves as an activator of T-cell factor (Tcf)-dependent transcription leading to an increased expression of several specific target genes including c-Myc, cyclin D1, MMP-7, and ITF-2. While APC mutations are almost exclusively found in colorectal cancers, deregulation of Wnt/beta-catenin/Tcf signaling is also common in other gastrointestinal and extra-gastrointestinal human cancers. In a fraction of hepatocellular carcinomas the Wnt pathway is deregulated by inactivation of Axin or stabilizing mutations of beta-catenin. The majority of hepatoblastomas and a group of gastric cancers also carry beta-catenin mutations. Clearly, this pathway harbors great potential for future applications in cancer diagnostics, staging, and therapy.
Efficient Intersection of Three Quadrics and Applications in Computer Vision (2016)

In this paper, we present a new algorithm for finding all intersections of three quadrics. The proposed method is algebraic in nature and it is considerably more efficient than the Gröbner basis and resultant-based solutions previously used in computer vision applications. We identify several computer vision problems that are formulated and solved as systems of three quadratic equations and for which our algorithm readily delivers considerably faster results. Also, we propose new formulations of three important vision problems: absolute camera pose with unknown focal length, generalized pose-and-scale, and hand-eye calibration with known translation. These new formulations allow our algorithm to significantly outperform the state-of-the-art in speed.
Ultra-low Von and High Voltage 4H-SiC Heterojunction Diode (2005)

We demonstrate a heterojunction diode (HJD) fabricated with p + -type polycrystalline silicon on an n - -type epitaxial layer of 4H-SiC. The HJD achieved extremely low Von and high reverse blocking voltage compared with a SiC Schottky barrier diode (SBD). The HJD shows good diode characteristics for temperatures ranging up to 200°C. Measured switching characteristics of the HJD exhibit almost zero reverse recovery similar to that of the SBD.
Odd aberrations and double-pass measurements of retinal image quality (1995)

We investigated the formation of the aerial image in the double-pass method to measure the optical quality of the human eye. We show theoretically and empirically that the double pass through the eye's optics forces the light distribution in the aerial image to be an even-symmetric function even if the single-pass point-spread function is asymmetric as a result of odd aberrations in the eye. The reason for this is that the double-pass imaging process is described by the autocorrelation rather than the autoconvolution of the single-pass point-spread functions, as has been previously assumed. This implies that although the modulation transfer function can be computed from the double-pass aerial image, the phase transfer function cannot. We also show that the lateral chromatic aberration of the eye cannot be measured with the double-pass procedure because it is canceled by the second pass through the eye's optics.
TGF-β1 in<i>Aplysia</i>: Role in Long-Term Changes in the Excitability of Sensory Neurons and Distribution of TβR-II-Like Immunoreactivity (1999)

Exogenous recombinant human transforming growth factor beta-1 (TGF-beta1) induced long-term facilitation of Aplysia sensory-motor synapses. In addition, 5-HT-induced facilitation was blocked by application of a soluble fragment of the extracellular portion of the TGF-beta1 type II receptor (TbetaR-II), which presumably acted by scavenging an endogenous TGF-beta1-like molecule. Because TbetaR-II is essential for transmembrane signaling by TGF-beta, we sought to determine whether Aplysia tissues contained TbetaR-II and specifically, whether neurons expressed the receptor. Western blot analysis of Aplysia tissue extracts demonstrated the presence of a TbetaR-II-immunoreactive protein in several tissue types. The expression and distribution of TbetaR-II-immunoreactive proteins in the central nervous system was examined by immunohistochemistry to elucidate sites that may be responsive to TGF-beta1 and thus may play a role in synaptic plasticity. Sensory neurons in the ventral-caudal cluster of the pleural ganglion were immunoreactive for TbetaR-II, as well as many neurons in the pedal, abdominal, buccal, and cerebral ganglia. Sensory neurons cultured in isolation and cocultured sensory and motor neurons were also immunoreactive. TGF-beta1 affected the biophysical properties of cultured sensory neurons, inducing an increase of excitability that persisted for at least 48 hr. Furthermore, exposure to TGF-beta1 resulted in a reduction in the firing threshold of sensory neurons. These results provide further support for the hypothesis that TGF-beta1 plays a role in long-term synaptic plasticity in Aplysia.
Improving RNA nearest neighbor parameters for helices by going beyond the two-state model (2018)

RNA folding free energy change nearest neighbor parameters are widely used to predict folding stabilities of secondary structures. They were determined by linear regression to datasets of optical melting experiments on small model systems. Traditionally, the optical melting experiments are analyzed assuming a two-state model, i.e. a structure is either complete or denatured. Experimental evidence, however, shows that structures exist in an ensemble of conformations. Partition functions calculated with existing nearest neighbor parameters predict that secondary structures can be partially denatured, which also directly conflicts with the two-state model. Here, a new approach for determining RNA nearest neighbor parameters is presented. Available optical melting data for 34 Watson-Crick helices were fit directly to a partition function model that allows an ensemble of conformations. Fitting parameters were the enthalpy and entropy changes for helix initiation, terminal AU pairs, stacks of Watson-Crick pairs and disordered internal loops. The resulting set of nearest neighbor parameters shows a 38.5% improvement in the sum of residuals in fitting the experimental melting curves compared to the current literature set.