gebhart/patrepeval huggingface dataset:
Transition Metal-Catalyzed Intramolecular [4 + 2] Cycloadditions:  A Novel Method for the Assembly of Nitrogen Heterocycles and Its Application to Yohimban Alkaloid Synthesis (1996)

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTTransition Metal-Catalyzed Intramolecular [4 + 2] Cycloadditions: A Novel Method for the Assembly of Nitrogen Heterocycles and Its Application to Yohimban Alkaloid SynthesisPaul A. Wender and Thomas E. SmithView Author Information Department of Chemistry, Stanford University, Stanford, California 94305Cite this: J. Org. Chem. 1996, 61, 3, 824–825Publication Date (Web):February 9, 1996Publication History Received8 November 1995Published online9 February 1996Published inissue 1 January 1996https://pubs.acs.org/doi/10.1021/jo9519827https://doi.org/10.1021/jo9519827rapid-communicationACS PublicationsCopyright © 1996 American Chemical SocietyRequest reuse permissionsArticle Views960Altmetric-Citations68LEARN 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-AlertscloseSupporting Info (1)»Supporting Information Supporting Information SUBJECTS:Addition reactions,Catalysts,Chemical reactions,Cyclization,Physical and chemical processes Get e-Alerts
THE ROLE OF CTLA4-MEDIATED NEGATIVE SIGNALS AND CELL SURVIVAL IN TOLERANCE INDUCTION BY BLOCKADE OF B7:CD28 AND CD40:CD40L (CD154). (1999)

915 The CTLA4 molecule, expressed at low levels on resting T cells and induced by T cell activation, transduces a negative signal to T cells which blocks IL-2 production, IL-2R expression, and induces cell cycle arrest. CTLA4 regulates both CD28 and non-CD28 mediated T cell activation, and has an important role in normal immune homeostasis, as demonstrated by lethal unchecked lymphoid proliferation in CTLA4 knockout mice. Here, we examined whether or not negative signals through CTLA4 play a role in the induction of transplantation tolerance by costimulatory blockade. B6 mice received vascularized BALB/c cardiac allografts. As reported previously by our group and others, tolerance was induced by the use of donor spleen cells in conjunction with either CTLA4Ig (given on day 2), anti-B7-1 + anti-B7-2 (day 2), or anti-CD40L (day 0). Mice also received a blocking anti-CTLA4 mAb at differing time points. (Table)TableThese data show that negative signals through CTLA4 are required for tolerance induction through B7 blockade, but not through blockade of CD40L:CD40. Furthermore, these signals are required only at the time of tolerance induction, and are not required for maintenance. To investigate the relative roles of B7-1 vs B7-2 in binding to CTLA4, we used B7-1′ BALB/c mice as heart donors. Surprisingly. CTLA4Ig was unable to induce long-term survival of B7-1′ hearts (rejected at days 7 - 39, n=8). The importance of an intact B7-1 pathway was also supported by the finding that blockade of B7-2 alone, on the day of transplantation, induced long-term graft survival (>100 days, n=5). Next, studies were undertaken to examine the role of apoptosis in tolerance induction. In mice transgenic for the cell survival gene Bcl-xL on the T cell lineage, we find that T cell apoptosis due to cytokine withdrawal, an event normally seen under conditions of costimulatory blockade, is prevented. Interestingly, these mice are completely resistant to tolerance induction with either CTLA4Ig or anti-CD40L (n=20). Together, these studies show a role for negative signals/apoptosis in the induction of tolerance. CTLA4 signals are required at the time of transplantation in strategies which inhibit CD28 costimulation. In contrast, apoptosis is required using either CD28 or CD40L blockade. The results also show, for the first time, that blockade of B7-2 alone can induce long-term graft survival. Finally, the data also strongly point to a key role for B7-1, expressed on donor cells, as the important CTLA4 ligand in this system.
Graphene-based fast electronics and optoelectronics (2010)

We present experimental results on high frequency field-effect transistors and fast photodetectors utilizing wafer-scale graphene grown epitaxially from silicon carbide.
Functional MR imaging of the monkey brain in a novel vertical large-bore 7 Tesla setup (2002)

Functional MRI in monkeys promises to build a bridge between brain research in humans and the large body of systems neuroscience work in animals [1]. Simultaneous fMRI and electrophysiology was recently used in the anesthetized monkey to elucidate the neural activity underlying the fMRI BOLD signal [2]. Here we present the first results from a novel high field (7T), large-bore (60cm) vertical MR system, in which MR imaging and electrophysiology can be performed in the awake trained monkey (Macaca mulatta). Upright positioning of the animal - being used over the last 50-years in all alert-monkey laboratories, was chosen for fMRI too, to minimize discomfort in the animals, expedite their training process, and ensure longer cooperation during the demanding psychophysical testing.
PmtA Regulates Pyocyanin Expression and Biofilm Formation in Pseudomonas aeruginosa (2021)

The opportunistic pathogen <i>Pseudomonas aeruginosa</i> expresses a small molecular weight, cysteine-rich protein (PmtA), identified as a metallothionein (MT) protein family member. The MT family proteins have been well-characterized in eukaryotes as essential for zinc and copper homeostasis, protection against oxidative stress, and the ability to modify a variety of immune activities. Bacterial MTs share sequence homology, antioxidant chemistry, and heavy metal-binding capacity with eukaryotic MTs, however, the impact of bacterial MTs on virulence and infection have not been well-studied. In the present study, we investigated the role of PmtA in <i>P. aeruginosa</i> PAO1 using a PmtA-deficient strain (Δ<i>pmtA</i>). Here we demonstrated the virulence factor, pyocyanin, relies on the expression of PmtA. We showed that PmtA may be protective against oxidative stress, as an alternative antioxidant, glutathione, can rescue pyocyanin expression. Furthermore, the expression of <i>phzM</i>, which encodes a pyocyanin precursor enzyme, was decreased in the Δ<i>pmtA</i> mutant during early stationary phase. Upregulated <i>pmtA</i> expression was previously detected in confluent biofilms, which are essential for chronic infection, and we observed that the Δ<i>pmtA</i> mutant was disrupted for biofilm formation. As biofilms also modulate antibiotic susceptibility, we examined the Δ<i>pmtA</i> mutant susceptibility to antibiotics and found that the Δ<i>pmtA</i> mutant is more susceptible to cefepime and ciprofloxacin than the wild-type strain. Finally, we observed that the deletion of <i>pmtA</i> results in decreased virulence in a waxworm model. Taken together, our results support the conclusion that PmtA is necessary for the full virulence of <i>P. aeruginosa</i> and may represent a potential target for therapeutic intervention.
Pilot study of cytokine profiles in prostate cancer patients undergoing proton or conventional radiotherapy (1996)

The mechanisms responsible for normal tissue late effects following radiotherapy are largely unknown and currently no method for predicting such risks is available. Abnormal levels of cytokine production induced by radiation has been suggested as a contributing factor by multiple investigators. The purpose of the present study was to evaluate plasma levels of transforming growth factor-beta 1 (TGF-beta 1), basic fibroblast growth factor (bFGF), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1 beta (IL-1 beta) in patients with prostate cancer scheduled for radiotherapy (protons, photons, or combination of both). It has been recently shown that ionizing radiation can increase expression of these cytokines and there are indications that they may be associated with morbidity. Blood samples were obtained from 20 subjects (age 51-80) before, during the first week, and immediately after the end of therapy; 3 healthy volunteers served as controls. Significant positive correlations (p<0.05) were obtained between bFGF, IL-1 beta, and TNF-alpha and the integral dose of radiation during the first week of treatment. Correlations approaching significance (p<0.1) were obtained with bFGF and acute treatment-related morbidity. A higher integral dose (due to larger irradiated volumes) was delivered with conventional photon compared to proton irradiation. No significance was obtained with any of the cytokines and pretreatment prostate specific antigen (PSA) levels, patient age, grade or stage of disease, or the integral dose by the end of radiation treatment. These results show that large changes occur in the plasma levels of certain cytokines early after initiation of radiotherapy and that treatment of larger volumes is more likely to induce these changes. Our data support further investigation of the role of cytokines during radiotherapy.
Neutron Time-of-Flight Measurements of Charged-Particle Energy Loss in Inertial Confinement Fusion Plasmas (2019)

Neutron spectra from secondary ^{3}H(d,n)α reactions produced by an implosion of a deuterium-gas capsule at the National Ignition Facility have been measured with order-of-magnitude improvements in statistics and resolution over past experiments. These new data and their sensitivity to the energy loss of fast tritons emitted from thermal ^{2}H(d,p)^{3}H reactions enable the first statistically significant investigation of charged-particle stopping via the emitted neutron spectrum. Radiation-hydrodynamic simulations, constrained to match a number of observables from the implosion, were used to predict the neutron spectra while employing two different energy loss models. This analysis represents the first test of stopping models under inertial confinement fusion conditions, covering plasma temperatures of k_{B}T≈1-4 keV and particle densities of n≈(12-2)×10^{24} cm^{-3}. Under these conditions, we find significant deviations of our data from a theory employing classical collisions whereas the theory including quantum diffraction agrees with our data.
Fabrication-Tolerant Nitride Lattice Filter for CWDM (2021)

We experimentally demonstrate an all-nitride passive 2-channel cascaded lattice filter with &lt;1.7nm (6σ) wavelength variation across four CMOS wafers by implementing fabrication insensitive MZI design.
Solid state neutron dosimeter for space applications (1992)

Under NASA sponsorship, the authors are developing a solid-state neutron sensor capable of being incorporated into a very compact flight instrument to provide high-quality real-time measurement of this important radiation flux. The dosimeter uses a special, high neutron sensitivity PIN diode that is insensitive to the other forms of ionizing radiation. The dosimeter will have the ability to measure and record neutron dose over a range of 50 microgray to tens of milligrays over a flight of up to 30 days. The performance characteristics of the PIN diode with a detailed description of the overall dosimeter is presented.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>
[Nevirapine related hepatotoxicity: the prevalence and risk factors in a cohort of ART naive Han Chinese with AIDS]. (2010)

NVP related hepatotoxicity was common among ARV naive HIV infected subjects in our cohort. Baseline ALT elevation and HCV co-infection were associated statistically with the development of hepatotoxicity. Hepatotoxicity led to discontinuing cART temporarily or switching to other regimens in some subjects. It suggested that NVP should be used with caution in patients co-infected with HCV among whom anti-HCV therapy before cART initiation may contribute to minimizing the probability of NVP associated hepatotoxicity.
M-CSF and 1,25 dihydroxy vitamin D3 synergize with 12-O-tetradecanoylphorbol-13-acetate to induce macrophage differentiation in acute promyelocytic leukemia NB4 cells. (1994)

NB4 cells were derived from a patient with acute promyelocytic leukemia (APL) and, unlike HL-60 cells, display the characteristic translocation t(15:17) involving the RAR alpha receptor. NB4 cells differentiate into granulocytes in response to all-trans retinoic acid, but little is known about the ability of these cells to form monocytes and macrophages. We show here that NB4 cells treated individually with a variety of agents, including recombinant human macrophage colony-stimulating factor (M-CSF), 1,25 dihydroxy vitamin D3 (1,25 D3) or 12-O-tetradecanoyl-phorbol-13-acetate (TPA), resulted in only partial or incomplete differentiation along the monocyte/macrophage pathway. However, when M-CSF was combined with TPA, or 1,25 D3 with TPA, a synergistic response was observed such that differentiation to fully functioning monocytes or macrophages occurred. In contrast, 1,25 D3 with M-CSF resulted in only a modest increase in the number of non-specific esterase positive cells and no increase in the phagocytic activity (ingestion of latex beads) when compared to either agent alone. We suggest that TPA and 1,25 D3 are monocyte/macrophage-specific differentiation inducing agents in NB4 cells but that both are required to achieve optimal macrophage function. We suggest a model for the synergistic action of TPA and 1,25 D3 and propose that inducing monocytic differentiation could also be considered in designing clinical protocols for the treatment of acute leukemia.
Fast Three-Dimensional Random Access Multi-Photon Microscopy for Functional Recording of Neuronal Activity (2007)

The dendritic processes of neurons have been shown to possess active and dynamic properties that give them the ability to modulate synaptic integration and shape individual synaptic responses. Effectively studying these properties at multiple locations on a live neuron in highly light scattering brain tissue requires an imaging/recording mechanism with high spatio-temporal resolution as well as optical sectioning and random access site selection capabilities. Our lab has made significant steps in developing such a system by combining the spatial resolution and optical sectioning ability of advanced imaging techniques such as confocal and multi-photon microscopy with the temporal resolution and random access capability provided by acousto-optic laser scanning. However, all systems that have been developed to date restrict fast imaging to two-dimensional (2D) scan patterns. This severely limits the extent to which many neurons can be studied since they represent complex three-dimensional (3D) structures. We have previously demonstrated a scheme for fast 3D scanning which utilizes a unique arrangement of acousto-optic deflectors and does not require axial movements of the objective lens. We have also shown how, when used with the ultra-fast laser pulses needed in multi-photon microscopy, this scheme inherently compensates for the spatial dispersion which would otherwise significantly reduce the resolution of acousto-optic based multi-photon microscopy. We have now coupled this scanning scheme to a modified commercial research microscope and use the combined system to effectively image user-defined sites of interest on fluorescent 3D structures with positioning times that are in the low microsecond (µs) range. The resulting random-access scanning mechanism allows for functional imaging of complex 3D structures such as neuronal dendrites at several thousand volumes per second.
Sagnac Loop Based Sensing System for Intrusion Localization Using Machine Learning (2022)

Among all optical sensing techniques, the distributed Sagnac loop (SI) sensor has the advantage of being simple to implement with low cost. Most of the proposed techniques for using SI exploit the frequency null method for event localization. However, such a technique suffers from the low spectrum signal power, complicating event localization under environmental noise. In this work, event localization using time-domain instead of frequency null signals is achieved using machine learning (ML), which is increasingly being exploited in many science fields, including sensing applications. First, a training dataset that includes 200 events is generated over a 50 km effective sensing fiber. These time-domain signals are considered as features for training the ML algorithm. Then, the random forest (RF) ML algorithm is used to develop a model for event location prediction. The results show the capability of ML in predicting the event’s location with 55 m mean absolute error (MAE). Further, the percentage of test realizations with prediction error &gt; 200 m is 0.7%. The sensing signal bandwidth is investigated, showing better performance results for sensing signals of larger bandwidths. Finally, the proposed model is validated experimentally. The results showed good accuracy with MAE &lt; 100 m.
5-Hydroxymethyl-2′-Deoxyuridine: Studies of Antileukemic Properties

in Vitro

and

in Vivo (1987)

Abstract 5-Hydroxymethyl-2-deoxyuridine (5HmdUrd) prolonged the survival of mice carrying leukemia L1210 in a dose-dependent manner. Furthermore, a dose-dependent synergism/antagonism was observed when human leukemia cells were exposed simultaneously to Ara-C and 5HmdUrd in vitro.
CHAPTER 12 RECO: REPRESENTATION AND EVALUATION OF CONFIGURABLE OFFERS (2003)

Up until now, electronic negotiations have primarily focused on the trading of simple goods and services, where products can be described either by price alone or as a set of attributes. There is little support for trading complex, configurable products, such as computer systems, automobiles, insurances and services in general. Companies need to communicate offers including complex rules and business policies, and they need decision support to evaluate these offers. This paper describes RECO, a decision support system for the representation and evaluation of configurable ofters. Configurable offers allow multiple values for each attribute and they include rules on how to combine the various attribute values and how to price a desired configuration. From a configurable offer, a user can extract offers for individual configurations. RECO provides a compact representation for configurable offers using prepositional logic, and helps a user in finding the top L configurations based on her preferences. In a multi-sourcing setting, it provides support for identifying the optimal sourcing strategy subject to considerations such as minimum/maximium number of winners and homogeneity of attributes across bids. We draw on mathematical programming, propositional logic and decision analysis. Configurable products, decision analysis, propositional logic, programming, XMLlEDI integer
Threshold voltage instability of p-channel metal-oxide-semiconductor field effect transistors with hafnium based dielectrics (2007)

Threshold voltage Vth instability is one major issue for future metal-oxide-semiconductor field effect transistors (MOSFETs) with hafnium (Hf) based gate dielectrics. Previous attention was focused on n-channel MOSFETs (nMOSFETs) and the implicit assumption is that it is not important for p-channel MOSFETs (pMOSFETs). This work shows that the Vth instability of pMOSEFTs can be higher than that of nMOSFETs for a sub-2nm nitrided Hf layer. Unlike nMOSFETs, the Vth instability of pMOSFETs is insensitive to measurement time, does not saturate as stress voltage increases, and is not controlled by carrier fluency. Using Hf silicates is less effective in suppressing it. Some speculations are given on the defect and physical processes responsible for the instability.
Critical and distinct roles for key RET tyrosine docking sites in renal development (2006)

Molecular mechanisms that lead to congenital anomalies of kidneys and the lower urinary tract (CAKUT) are poorly understood. To elucidate the molecular basis for signaling specificity of GDNF-mediated RET signaling in kidney development, we characterized mice that exclusively express either the human RET9 or RET51 isoform, or express these isoforms with individual mutations in docking tyrosines for PTB and SH2-domain-containing adaptors Src (Y981), PLCgamma (Y1015), and Shc (Y1062). Our results provide evidence for differential and isoform-specific roles of these docking sites in murine kidney development. Homozygous Ret(RET9) and Ret(RET51) mice were viable and show normally developed kidneys, indicating redundant roles of human RET isoforms in murine kidney development. In the context of the RET51 isoform, only mutation of the docking Tyr 1015 (Y1015F) resulted in severe renal anomalies. These included bilateral megaureters and multicystic kidneys that were caused by supernumerary ureteric buds that fail to separate from the wolffian duct as well as decreased branching morphogenesis. Similar kidney and ureter defects were observed in RET9(Y1015F) mice that contain the Y1015F mutation in the RET9 isoform. Interestingly, loss of RET9(Y1062)-mediated AKT/MAPK activation resulted in renal agenesis or kidney rudiments, whereas mutation of this residue in RET51 had no obvious effect on AKT/MAPK activity and renal development. These results reveal novel roles of key RET-dependent signaling pathways in embryonic kidney development and provide murine models and new insights into the molecular basis for CAKUT.
Paf‐acether in human skin (1991)

Paf is a phospholipid mediator present in human skin which induces inflammatory events, such as neutrophil infiltration and increased vascular permeability. Recent data suggest that cutaneous cells, such as fibroblasts and keratinocytes, produce paf and that paf is released during allergic cutaneous reactions. It is tempting to speculate that paf may contribute to the development of various skin disorders with acute and chronic skin inflammation. Paf antagonists may help in bringing answers to this hypothesis and may offer new prospects for the treatment of cutaneous inflammatory diseases.
Ultrafast coherent optical signal processing using stabilized optical frequency combs from mode-locked semiconductor diode lasers (2015)

Optical frequency combs are used as a set of mutually coherently orthogonal signals to realize high speed signal processing. Here, we demonstrate novel comb sources, along with modulation and detection techniques that realize high speed sampling, arbitrary waveform generation and matched filtering functionality.