gebhart/patrepeval huggingface dataset:
Atom-transfer addition, annulation, and macrocyclization reactions of iodomalononitriles (1990)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAtom-transfer addition, annulation, and macrocyclization reactions of iodomalononitrilesDennis P. Curran and Churl Min SeongCite this: J. Am. Chem. Soc. 1990, 112, 25, 9401–9403Publication Date (Print):December 1, 1990Publication History Published online1 May 2002Published inissue 1 December 1990https://pubs.acs.org/doi/10.1021/ja00181a057https://doi.org/10.1021/ja00181a057research-articleACS PublicationsRequest reuse permissionsArticle Views854Altmetric-Citations95LEARN 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 Get e-Alerts
Tools for anti‐inflammatory drug design: In vitro models of leukocyte migration (2004)

Inhibiting leukocyte recruitment is now a major focus in the design of novel anti-inflammatory drugs. Following the identification of lead compounds from conventional high-throughput screens using appropriate receptors or enzymes, it is important to validate the action of the compounds in a suitable in vitro model of leukocyte migration. Here, we review a range of different experimental approaches to modelling leukocyte migration, and identify the multi-well filter migration assay as the best compromise between the amount of resources required to screen multiple compounds and the amount of information gained about the effects of the compounds on cell movement behavior. However, there are pitfalls in the interpretation of data obtained using the multi-well filter migration assay, which arise from the imperfect correlation between the number of cells undergoing migration and the inhibitory activity of the test substances. We examine a number of such pitfalls and provide practical approaches to mitigate these problems as far as possible. We recommend a general strategy for screening inhibitors of cell migration using in vitro functional assays. While being more resource intensive than surrogate measures such as calcium flux, functional approaches nevertheless provide superior correlations with anti-inflammatory activity in vivo.
Jointly Managing Electrical and Thermal Energy in Solar- and Battery-powered Computer Systems (2023)

Environmentally-powered computer systems operate on renewable energy harvested from their environment, such as solar or wind, and stored in batteries. While harvesting environmental energy has long been necessary for small-scale embedded systems without access to external power sources, it is also increasingly important in designing sustainable larger-scale systems for edge applications. For sustained operations, such systems must consider not only the electrical energy but also the thermal energy available in the environment in their design and operation. Unfortunately, prior work generally ignores the impact of thermal effects, and instead implicitly assumes ideal temperatures. To address the problem, we develop a thermodynamic model that captures the interplay of electrical and thermal energy in environmentally-powered computer systems. The model captures the effect of environmental conditions, the system’s physical properties, and workload scheduling on performance. In evaluating our model, we distill the thermal effects that impact these systems using a small-scale prototype and a programmable incubator. We then leverage our model to show how considering these thermal effects in designing and operating environmentally-powered computer systems of varying scales can improve their energy-efficiency, performance, and availability.
GPS-optimal micro air vehicle navigation in degraded environments (2014)

We investigate a computationally and memory efficient algorithm for radio frequency (RF) source-seeking with a single-wing rotating micro air vehicle (MAV) operating in an urban canyon environment. We present an algorithm that overcomes two significant difficulties of operating in an urban canyon environment. First, Global Positioning System (GPS) localization quality can be degraded due to the lack of clear line of sight to a sufficient number of GPS satellites. Second, the spatial RF field is complex due to multipath reflections leading to multiple maxima and minima in received signal strength (RSS). High quality GPS localization is maintained by observing the GPS signal to noise ratio (SNR) to each satellite and making inferences about directions of high GPS visibility (allowable) and directions of low GPS visibility (forbidden). To avoid local maxima in RSS due to multipath reflections we exploit the rotation of the MAV and the directionality of its RF antenna to derive estimates of the angle of arrival (AOA) at each rotation. Under mild assumptions on the noise associated with the AOA measurements, a greedy algorithm is shown to exhibit a global recurrence property. Simulations supplied with actual GPS SNR measurements indicate that this algorithm reliably finds the RF source while maintaining an acceptable level of GPS visibility. Additionally, outdoor experiments using Lockheed Martin's Samarai MAV demonstrate the efficacy of this approach for static source-seeking in an urban canyon environment.
SOX2 promotes lineage plasticity and antiandrogen resistance in TP53 - and RB1 -deficient prostate cancer (2017)

Some cancers evade targeted therapies through a mechanism known as lineage plasticity, whereby tumor cells acquire phenotypic characteristics of a cell lineage whose survival no longer depends on the drug target. We use in vitro and in vivo human prostate cancer models to show that these tumors can develop resistance to the antiandrogen drug enzalutamide by a phenotypic shift from androgen receptor (AR)-dependent luminal epithelial cells to AR-independent basal-like cells. This lineage plasticity is enabled by the loss of TP53 and RB1 function, is mediated by increased expression of the reprogramming transcription factor SOX2, and can be reversed by restoring TP53 and RB1 function or by inhibiting SOX2 expression. Thus, mutations in tumor suppressor genes can create a state of increased cellular plasticity that, when challenged with antiandrogen therapy, promotes resistance through lineage switching.
Heterologous expression of cyanobacterial gas vesicle proteins in Saccharomyces cerevisiae (2021)

Given the potential applications of gas vesicles (GVs) in multiple fields including antigen-displaying and imaging, heterologous reconstitution of synthetic GVs is an attractive and interesting study that has translational potential. Here, we attempted to express and assemble GV proteins (GVPs) into GVs using the model eukaryotic organism Saccharomyces cerevisiae. We first selected and expressed two core structural proteins, GvpA and GvpC from cyanobacteria Anabaena flos-aquae and Planktothrix rubescens, respectively. We then optimized the protein production conditions and validated GV assembly in the context of GV shapes. We found that when two copies of anaA were integrated into the genome, the chromosomal expression of AnaA resulted in GV production regardless of GvpC expression. Next, we co-expressed chaperone-RFP with the GFP-AnaA to aid the AnaA aggregation. The co-expression of individual chaperones (Hsp42, Sis1, Hsp104, and GvpN) with AnaA led to the formation of larger inclusions and enhanced the sequestration of AnaA into the perivacuolar site. To our knowledge, this represents the first study on reconstitution of GVs in S. cerevisiae. Our results could provide insights into optimizing conditions for heterologous protein production as well as the reconstitution of other synthetic microcompartments in yeast.
Annotation-free probabilistic atlas learning for robust anatomy detection in CT images (2015)

A fully automatic method generating a whole body atlas from CT images is presented. The atlas serves as a reference space for annotations. It is based on a large collection of partially overlapping medical images and a registration scheme. The atlas itself consists of probabilistic tissue type maps and can represent anatomical variations. The registration scheme is based on an entropy-like measure of these maps and is robust with respect to field-of-view variations. In contrast to other atlas generation methods, which typically rely on a sufficiently large set of annotations on training cases, the presented method requires only the images. An iterative refinement strategy is used to automatically stitch the images to build the atlas. Affine registration of unseen CT images to the probabilistic atlas can be used to transfer reference annotations, e.g. organ models for segmentation initialization or reference bounding boxes for field-of-view selection. The robustness and generality of the method is shown using a three-fold cross-validation of the registration on a set of 316 CT images of unknown content and large anatomical variability. As an example, 17 organs are annotated in the atlas reference space and their localization in the test images is evaluated. The method yields a recall (sensitivity), specificity and precision of at least 96% and thus performs excellent in comparison to competitors.
In Vitro Performance Testing of a Pediatric Oxygenator With an Integrated Pulsatile Pump (2012)

For different lung and heart diseases (e.g., acute respiratory distress syndrome, congenital heart failure, and cardiomyopathy) extracorporeal membrane oxygenation is a well-established therapy, particularly in the field of neonatal and pediatric medicine. To reduce the priming volume of the extracorporeal circuit, different components can be combined. In this study, an oval-shaped oxygenator (called ExMeTrA) with integrated pulsatile pump was tested in vitro using porcine blood. A feasibility study regarding the performance of collapsing and expanding silicone tubes within an oxygenator fiber bundle as a pulsatile pump was previously completed with successful results. The findings of this study improve upon the previous feasibility results, particularly in terms of gas exchange and filling volume. Five modules were manufactured in sizes of 20 ± 2.2 ml (priming volume) with fiber surface areas of 0.24 ± 0.027 m(2) and an analytically calculated volume pumping capacity of 692 ± 75 ml/min. The modules were made of polymethylpentene fibers with dense outer layer to permit long-term applications. The gas exchange rates at a gas/blood flow ratio of 2:1 were between 64 and 72.7 ml(O)(2)/l(blood) and between 62.5 and 81.5 ml/l(blood), depending on the blood flow. The individual module's pumping capacity ranged from 200-500 ml/min thus providing room for further improvements. In order to enhance the pumping capacity while maintaining sufficient gas exchange rates future optimization, adjustments will be made to the inlet and outlet geometries.
Enantioselective Synthesis of the Optically Active α-Methylene-β-hydroxy Esters, Equivalent Compounds to Morita−Baylis−Hillman Adducts, Using Successive Asymmetric Aldol Reaction and Oxidative Deselenization (2005)

[Chemical reaction: See text] The asymmetric aldol reaction of a tetra-substituted ketene silyl acetal including an alkylseleno group with aldehydes has been developed by the promotion of Sn(OTf)2 coordinated with a chiral diamine to afford the corresponding aldols having chiral quaternary centers at the alpha-positions. The facile oxidative deselenization of these aldol compounds produces optically active alpha-methylene-beta-hydroxy esters which correspond to adducts prepared by the asymmetric Morita-Baylis-Hillman reaction.
ChemInform Abstract: Conversion of Glycosyl Azides via N‐Bromoglycosylimines to Aldononitriles. (1994)

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.
Extreme Ultraviolet Resist Fabricated Using Water Wheel-Like Cyclic Oligomer with Pendant Adamantyl Ester Groups (2011)

The synthesis and properties of water wheel-like cyclic oligomer (noria PY ) derivatives (noria PY -ADs) with pendant adamantyl ester (AD) groups were examined for their application as extreme ultraviolet (EUV) resist materials. Noria PY -ADs with various degrees of introduction (DI values) of AD groups were synthesized by adjusting the reactant feed ratios and reaction concentration. Solubility, film-forming property, and thermal stability were consistent with differences in DI values. The patterning properties of noria PY -AD 25 (DI= 25%) were examined in an EUV resist system, and noria PY -AD 25 provided a clear line-and-space pattern with 30 nm resolution and a line width roughness (LWR) of 11.3 nm.
Spin-transfer-torque-induced rf oscillations in CoFeB/MgO/CoFeB magnetic tunnel junctions under a perpendicular magnetic field (2010)

We investigated spin-transfer-torque (STT)-induced rf oscillation with a magnetic field applied perpendicular to the plane of CoFeB/MgO/CoFeB magnetic tunnel junctions (MTJs). For the rf measurement with the magnetic field normal to the MTJ plane, the magnetic field dependence of the peak frequency $({f}_{0})$, the linewidth $(\ensuremath{\Delta}f)$, and the power spectral density (PSD) were well interpreted as behavior in a linear regime, which showed the minima of ${f}_{0}$ and $\ensuremath{\Delta}f$ and the maximum of PSD at the demagnetizing field of the free layer. However, no clear onset of STT-induced rf oscillation was observed even with a large bias current applied. Under the magnetic field slightly tilted from the normal direction, on the other hand, the spectral shape strongly depended on the bias current. With the current in the direction to stimulate STT-induced rf oscillation, a rapid blueshift of ${f}_{0}$ and an abrupt increase in PSD were observed together with a remarkable broadening of $\ensuremath{\Delta}f$, indicating that STT-induced rf oscillation was achieved. The critical current for STT-induced rf oscillation estimated from the variation in $\ensuremath{\Delta}f$ was also in good agreement with the bias current at which the peak of the second harmonics of ${f}_{0}$ appeared in the rf spectrum.
51.1-Tbit/s MCF Transmission Over 2520 km Using Cladding-Pumped Seven-Core EDFAs (2015)

Multicore erbium-doped fiber amplifiers (MC-EDFAs) are essential components to achieve long-haul multicore fiber (MCF) transmission. An attractive technique for reducing the number of components and power consumption is the cladding-pumping scheme in MC-EDFAs in which all cores are simultaneously pumped using a single high-power multimode laser diode. In this paper, we experimentally demonstrate long-haul MCF transmission using cladding-pumped seven-core EDFAs. We confirm that 73 × 128-Gbit/s Nyquist-pulse-shaped dual-polarization quadrature phase-shift keying signals are successfully transmitted over 2520-km seven-core fiber.
mTORC1 Activation Regulates β-Cell Mass and Proliferation by Modulation of Cyclin D2 Synthesis and Stability (2009)

Growth factors, insulin signaling, and nutrients are important regulators of beta-cell mass and function. The events linking these signals to the regulation of beta-cell mass are not completely understood. The mTOR pathway integrates signals from growth factors and nutrients. Here, we evaluated the role of the mTOR/raptor (mTORC1) signaling in proliferative conditions induced by controlled activation of Akt signaling. These experiments show that the mTORC1 is a major regulator of beta-cell cycle progression by modulation of cyclin D2, D3, and Cdk4 activity. The regulation of cell cycle progression by mTORC1 signaling resulted from modulation of the synthesis and stability of cyclin D2, a critical regulator of beta-cell cycle, proliferation, and mass. These studies provide novel insights into the regulation of cell cycle by the mTORC1, provide a mechanism for the antiproliferative effects of rapamycin, and imply that the use of rapamycin could negatively impact the success of islet transplantation and the adaptation of beta-cells to insulin resistance.
NRF2 Rewires Cellular Metabolism to Support the Antioxidant Response (2016)

The transcription factor (nuclear factor-erythroid 2 p45-related factor 2, NRF2) is a master regulator of the cellular response to oxidative insults. While antioxidant response enzymes are well-characterized transcriptional targets of NRF2, it is recently becoming clear that NRF2 also supports cellular detoxification through metabolic rewiring to support the antioxidant systems. In this chapter, we discuss the regulation of NRF2 and how NRF2 activation promotes the antioxidant defense of cells. Furthermore, we discuss how reactive oxygen species influence cellular metabolism and how this affects antioxidant function. We also discuss how NRF2 reprograms cellular metabolism to support the antioxidant response and how this functions to funnel metabolic intermediates into antioxidant pathways. This chapter concludes by exploring how these factors may contribute to both normal physiology and disease.
Characterizing high-bandwidth real-time video traffic in residential broadband networks (2010)

Abstract—Users are generating and uploading multimedia content to the Internet at an unprecedented rate. Residential broadband networks, however, have low upload capacities and large packet latencies. Wi-Fi networks that are used to access the Internet can suffer from high packet losses and contention latencies. All of these factors can result in poor video quality for residential users. Using packet traces and active measurements from houses, we study video quality in residential scenarios. We analyze the primary factors that contribute to poor performance and compare the performance over both the wireless and the broadband hop. Our measurements show that the upload capacities on the broadband links restrict the video bitrate (and hence the resolution) that can be transmitted. Residential wireless networks, however, have much higher capacities than the broadband links and, despite being densely deployed, do not see extended periods of high utilization. Our measurements shed light on the video transmission quality that is typically achievable from residences and are used to characterize the reasons behind quality deterioration. I.
SPECIAL REPORTS AND REVIEWS A Review of Activity Indices and Efficacy End Points for Clinical Trials of Medical Therapy in Adults With Ulcerative Colitis (2007)

tive example of the use of a measurement in a clinical trial (in some instances for regulatory approval). The task force met initially in person for discussion. The results were summarized in a draft manuscript by the primary authors (G.D. and W.J.S.) and discussed at the annual IOIBD meetings in 2004 and 2005. The manuscript was then circulated to the entire IOIBD membership; the leadership of the European Crohn’s and Colitis Organization (ECCO); the leadership of 3 groups of investigators who conduct clinical trials in inflammatory bowel disease (IBD) in the United States (the clinical alliance of the Crohn’s and Colitis Foundation of America), Canada (the clinical network of the Crohn’s and Colitis Founda
Chain-Growth SuFEx Polycondensation: Molecular Weight Control and Synthesis of Degradable Polysulfates (2021)

Sulfur (Ⅵ) fluoride exchange (SuFEx) click chemistry has offered a facile and reliable approach to produce polysulfates and polysulfonates. However, the current SuFEx polymerization methods lack precise control of target molecular weight and dispersity. Herein, we report the first chain-growth SuFEx polycondensation process by exploiting unique reactivity and selectivity of S-F bonds under SuFEx catalysis. Given the higher reactivity of iminosulfur oxydifluoride versus fluorosulfate, the chain-growth SuFEx polycondensation is realized by using an iminosulfur oxydifluoride-containing compound as the reactive chain initiator and deactivated AB-type aryl silyl ether-fluorosulfates bearing an electron-withdrawing group as monomers. When DBU was utilized as the polymerization catalyst, precise control over polymer molecular weight and polydispersity are achieved. The resulting polymers possess great thermal stability but are easily degradable under mild acidic and basic conditions.
Nonlinear standing wave excitation by series resonance-enhanced harmonics in low pressure capacitive discharges (2015)

It is well-known that standing waves having radially center-high rf voltage profiles exist in high frequency capacitive discharges. It is also known that in radially uniform discharges, the capacitive sheath nonlinearities excite strong nonlinear series resonance harmonics that enhance the electron power deposition. In this work, we consider the coupling of the series resonance-enhanced harmonics to the standing waves. A one-dimensional, asymmetric radial transmission line model is developed incorporating the wave and nonlinear sheath physics and a self-consistent dc potential, for both conducting and insulating electrode surfaces. The resulting coupled pde equation set is solved numerically to determine the discharge voltages and currents. A 10 mTorr argon plasma is chosen with density m−3, gap width 2 cm and conducting electrode radius 15 cm, driven by a 500 V rf source with resistance 0.5 . We examine a set of frequencies from near 30 MHz up to frequencies more than three times as high. For most frequencies, no harmonics correspond exactly with the series or spatial resonances, which is the generic situation. Nevertheless, nearby resonances lead to a significantly enhanced ratio of the electron power per unit area on axis, compared to the average. Nearly similar results are found for insulating electrodes. Strong effects are seen for varying source resistance: high (50 ) resistance damps out most of the harmonic activity, while zero source resistance leads to a non-steady discharge with bias voltage relaxation oscillations. Stronger harmonic effects are seen for an increased radius of 30 cm, as lower harmonics become spatially resonant at lower frequencies. The radial dependence of electron power with frequency showed significant variations, with the central enhancement and sharpness of the spatial resonances depending in a complicated way on the amplitudes of the nearby series resonance current harmonics and the phase relations among the voltage harmonics driving these current harmonics. Significant center/average electron power per unit area enhancement is found even at the lowest frequencies for both high and low densities: 4.5 at 30 MHz and m−3, and 2.2 at m−3.