gebhart/patrepeval huggingface dataset:
Facile Strategy for Intrinsic Low-<i>k</i> Dielectric Polymers: Molecular Design Based on Secondary Relaxation Behavior (2019)

An original design strategy for the preparation of polymers with a low dielectric constant is presented. The key to this design strategy is taking the most advantage of the secondary relaxation behavior of the polymer chains to obtain more free volume in the bulk, which can effectively reduce the dielectric constant of the polymer. By using this design strategy, we have successfully synthesized a novel polyimide TmBPHF with a pendant group that consists of a biphenyl unit attached to the meta-position of a phenyl ring that is part of a triaryl unit. The intrinsic k and dielectric loss values of the TmBPHF are 2.09 and 0.0012 at 10 kHz, respectively. More importantly, such outstanding low-k performance remains stable up to 300 °C. The excellent low-k performance of TmBPHF is mainly due to the secondary relaxation, especially the β relaxation, which occurs from the rotation of the pendant group. The TmBPHF film shows an ultralow moisture rate (∼0.17%), which is able to maintain the low-k property stability in different humid environments. Meanwhile, the TmBPHF film also shows excellent thermal stability and excellent mechanical properties, with a glass transition temperature (Tg) of 302 °C, 5 wt % decomposition temperature (Td5%) of 549 °C, and residual of 70% at 800 °C under N2. The tensile strength and tensile modulus of the polyimide film are equal to 85.8 MPa and 2.02 GPa, respectively. In addition, the TmBPHF film is soluble in common solvents, which allows simple solution processing and efficient, low-cost, and continuous roll-to-roll processes. The design strategy is beneficial for lowering the k value and simultaneously maintaining the overall properties of polyimides, which possibly could also be extended to other novel high-performance polymer systems.
Strongly Injection-Locked Whistle-Geometry Microring Lasers for Optical Communications at 100 GHz and Beyond (2019)

Large-signal analog modulation of strongly injection-locked single and cascaded whistle-geometry semiconductor ring lasers is analyzed. Advantages of strong injection locking for high-fidelity large-signal modulation are confirmed through numerical modeling.
Production, purification, and characterization of a highly glucose-tolerant novel beta-glucosidase from Candida peltata (1996)

Candida peltata (NRRL Y-6888) produced beta-glucosidase when grown in liquid culture on various substrates (glucose, xylose, L-arabinose, cellobiose, sucrose, and maltose). An extracellular beta-glucosidase was purified 1,800-fold to homogeneity from the culture supernatant of the yeast grown on glucose by salting out with ammonium sulfate, ion-exchange chromatography with DEAE Bio-Gel A agarose, Bio-Gel A-0.5m gel filtration, and cellobiose-Sepharose affinity chromatography. The enzyme was a monomeric protein with an apparent molecular weight of 43,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration. It was optimally active at pH 5.0 and 50 degrees C and had a specific activity of 108 mumol.min-1.mg of protein-1 against p-nitrophenyl-beta-D-glucoside (pNP beta G). The purified beta-glucosidase readily hydrolyzed pNP beta G, cellobiose, cellotriose, cellotetraose, cellopentaose, and cellohexaose, with Km values of 2.3, 66, 39, 35, 21, and 18 mM, respectively. The enzyme was highly tolerant to glucose inhibition, with a Ki of 1.4 M (252 mg/ml). Substrate inhibition was not observed with 40 mM pNP beta G or 15% cellobiose. The enzyme did not require divalent cations for activity, and its activity was not affected by p-chloromercuribenzoate (0.2 mM), EDTA (10 mM), or dithiothreitol (10 mM). Ethanol at an optimal concentration (0.75%, vol/vol) stimulated the initial enzyme activity by only 11%. Cellobiose (10%, wt/vol) was almost completely hydrolyzed to glucose by the purified beta-glucosidase (1.5 U/ml) in both the absence and presence of glucose (6%). Glucose production was enhanced by 8.3% when microcrystalline cellulose (2%, wt/vol) was treated for 24 h with a commercial cellulase preparation (cellulase, 5 U/ml; beta-glucosidase, 0.45 U/ml) that was supplemented with purified beta-glucosidase (0.4 U/ml).
LASERS IN STRUCTURAL MONITORING (1988)

This article describes an automatic laser monitoring system, which directly measures structural movements as and when they occur. The system differs from more traditional methods in that it: a) can be left unattended almost indefinitely; b) directly provides positional information in both the x and y axis (the z axis being the laser itself); c) can be programmed to take rapid and repeated readings at rates up to 2 hz; and d) can be set to provide an automatic alarm should movements be in excess of pre-selected limits. As with traditional surveys there is a need for a stable datum and a clear line of sight. The system uses a low powered laser to create the reference line. The laser beam spans the relevant part of the structure and is targeted on to a light sensitive receiver, located at the far end of the sight line. Detectors are rigidly attached to the structure at various points along the path of the laser. All movements of the structure at these detector locations result in a corresponding movement relative to the reference beam. Timing, the control of the operational sequence, and calculation of movement is controlled by computer. Only relevant information is recorded. Software has been written to enable irrelevant information to be filtered out by ascribing ranges of allowable movement for each detector station. Only measurements that fall outside those ranges are recorded. Accuracy is within plus or minus 0.25 mm.
Activation of the Arterial Program Drives Development of Definitive Hemogenic Endothelium with Lymphoid Potential (2018)

Understanding the pathways guiding the development of definitive hematopoiesis with lymphoid potential is essential for advancing human pluripotent stem cell (hPSC) technologies for the treatment of blood diseases and immunotherapies. In the embryo, lymphoid progenitors and hematopoietic stem cells (HSCs) arise from hemogenic endothelium (HE) lining arteries but not veins. Here, we show that activation of the arterial program through ETS1 overexpression or by modulating MAPK/ERK signaling pathways at the mesodermal stage of development dramatically enhanced the formation of arterial-type HE expressing DLL4 and CXCR4. Blood cells generated from arterial HE were more than 100-fold enriched in T cell precursor frequency and possessed the capacity to produce B lymphocytes and red blood cells expressing high levels of BCL11a and β-globin. Together, these findings provide an innovative strategy to aid in the generation of definitive lymphomyeloid progenitors and lymphoid cells from hPSCs for immunotherapy through enhancing arterial programming of HE.
Graph-based seed selection for web-scale crawlers (2009)

One of the most important steps in web crawling is determining the starting points, or seed selection. This paper identifies and explores the problem of seed selection in web-scale incremental crawlers. We argue that seed selection is not a trivial but very important problem. Selecting proper seeds can increase the number of pages a crawler will discover, and can result in a repository with more "good" and less "bad" pages. We propose a graph-based framework for crawler seed selection, and present several algorithms within this framework. Evaluation on real web data showed significant improvements over heuristic seed selection approaches.
A New Optical Network-on-Chip Architecture for Chip Multiprocessor (2015)

A screwy torus topology (STorus) is proposed to improve the performance of network that memory access oriented. STorus divides an optical network into two subnets, and employs waveguide hierarchy. Comparisons between STorus and mesh are made, connecting with 4 memory controllers.
ALAN: A (Circuit-Switched) Local Area Network (1985)

Our view is that people (that is, programmers and general computer users) tend to work together in small groups, where information and resources are shared freely within a group. Most interactions occur within the group (called a cluster)-sending messages, exchanging data, sharing a printer. Communication outside the cluster-sending mail to someone in another group or using a large number cruncher-is comparalively rare. Under this hypothesis, it is advantageous to optimize and simplify interactions within the group. This paper describes our attempt to design a cluster network based on a nonblocking crosspoint switch, which we call ALAN (a local area net). ALAN clusters are star-connected-with intelligent workstation nodes (PC's) at the points of the star, and the ALAN switch at the center.
<i>N</i>‐Myristoyl‐transferase activity in cancer cells (1991)

The activity catalyzed by N-myristoyl transferase (NMT) is described for the first time in microsome-rich fractions from the murine leukemia cell line L1210, rat brain and mouse liver as biological sources. The enzyme from each source can accommodate various types of proteins (protein kinase A, virus structural gag protein or pp60src) as modelized by the use of their N-terminal derived peptides (GNAAAARR, GQTVTTPL and GSSKSKPKDP, respectively). As for some other types of membrane-bound enzymes, NMT activity can be enhanced by pretreatment with various types of detergents, amongst which Triton 770 and deoxycholate were the most potent. Further experiments on the L1210 microsome-rich fractions demonstrate that these two detergents were able to solubilize the microsomal enzyme, without modifying its substrate specificity. Finally, three compounds described in the literature to be inhibitors of NMT activity from other sources were tested for L1210 microsome-associated activity. None of them show any significant potency in inhibiting this activity. A new compound, myristoylphenylalanine, shows a slightly better inhibitory effect on the L1210 microsomal activity than the reference compounds with a median inhibitory concentration (IC50) of 0.2 mM.
Nonlinear beamforming for enhancing prestack seismic data with a challenging near surface or overburden (2018)

Modern land seismic data acquisition is moving from sparse grids of large source/receiver arrays to denser grids of smaller arrays or point-source, point-receiver systems. Large arrays were designed to attenuate ground-roll and backscattered noise and to increase overall signal-to-noise ratio (SNR). An example of a typical raw common-shot gather acquired using a legacy acquisition design with 72 geophones in a group and five vibrators per sweep is shown in Figure 1b. We can clearly see that the ground-roll noise with low apparent velocity was partially attenuated by field arrays, and reflection events with high apparent velocity are strong and can be reliably identified. Decreasing the size of field arrays during acquisition in arid environments leads to dramatic decrease in data SNR. An example of raw common-shot gather from a 2D line acquired using a single-sensor survey is shown in Figure 1a. In contrast to legacy data, the single-sensor data is dominated by noise caused by severe multiple scattering in complex near-surface layers and shows no apparent evidence of reflection signal. The sources and receivers were spaced at 10 m intervals in this recent 2D single-sensor survey. This sampling involves much denser acquisition compared to the conventional data using intervals of 30 m or more. Theoretically, high-density seismic acquisition better samples the entire wavefield (signal and noise) and is expected to result in improved imaging. Achieving this in practice with huge amounts of low SNR data proves to be very challenging. Conventional time processing tools such as surface-consistent scaling, deconvolution, static corrections, require reliable prestack signal in the data. Their application to modern seismic datasets acquired with small arrays often leads to unreliable results because the derived operators are based on noise and not on the expected signal. To extract the maximum value from dense high-channel acquisition, we need to enhance signal in the prestack data. Fortunately, densely sampled data gives us more flexibility than grouping geophones directly in the field.
Tolerance to defective memristors in a neuromorphic learning circuit (2014)

This paper describes a memristor based neuromorphic circuit that is capable of learning. Target memristors within the crossbar circuit were set to be stuck in either high or low resistance states to observe fault tolerance within the memristor crossbar. The simulations are carried out in SPICE using a detailed memristor model so that the crossbar is simulated as accurately as possible. In some cases the circuit was able to successfully learn when half of the memristors in the crossbar were set to be defective. Due to additional bias circuitry, this neuromorphic memristive learning circuit appears to be more tolerant to error than alternative designs.
Synthesis of Reflective Polyimide Films via in Situ Silver(I) Reduction (1995)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis of Reflective Polyimide Films via in Situ Silver(I) ReductionRobin E. Southward, D. Scott Thompson, David W. Thompson, Maggie L. Caplan, and Anne K. St. ClairCite this: Chem. Mater. 1995, 7, 11, 2171–2180Publication Date (Print):November 1, 1995Publication History Published online1 May 2002Published inissue 1 November 1995https://pubs.acs.org/doi/10.1021/cm00059a027https://doi.org/10.1021/cm00059a027research-articleACS PublicationsRequest reuse permissionsArticle Views341Altmetric-Citations25LEARN 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
Multi-band software defined radio for spaceborne communications, navigation, radio science, and sensors (2010)

Demanding mass and power requirements across many low-cost NASA mission sets (Discovery, New Frontiers, Mars Scout, SMEX, MIDEX, and others) place a premium on lightweight, efficient, and versatile radios. A low power, low mass, modular, multi-band software-defined radio (SDR) has been developed by JHU/APL, under the name Frontier Radio, for use in communications, navigation, radio science, and sensor applications for a variety of NASA missions. The current SDR implementation features communications and Doppler navigation modes, and provides a highly capable platform to build upon for future technology enhancements. Features such as in-band channel assignment, bit rate, modulation format, turnaround ratio, loop bandwidths, and coding formats are reconfigurable in flight. Modularity within the core hardware and firmware platforms enable infusion of new technology with minimal non-recurring engineering (NRE) costs. Current configurations operate within the NASA S, X (under development), and Ka-bands (26 and 32 GHz), though alternate RF slices may be added and/or substituted for other bands or sensor applications. This SDR is currently capable of transmit data rates up to 25 Mbps (and higher with 8/16 PSK/QAM) and receive data rates up to 1.3 Mbps via QPSK, with significantly higher capability under development. Compatibility with NASA's STRS architecture helps promote the use of this SDR throughout the NASA community. Along with its low power (5 W receive mode w/internal ovenized oscillator and 28 V bus power) and low mass (1.8/2.1 kg, single/dual band configuration), this SDR offers missions a combination of capabilities and efficiency. The NASA Radiation Belt Storm Probes (RBSP) mission is currently developing a flight implementation of this SDR (S-Band only), with launch planned for the year 2012.
Spectrally controlled interferometry for improved radius of curvature measurement (2019)

Spectrally controlled interferometry offers advantages for radius of curvature measurements for spherical optics by removing the catseye position during measurement and exploiting the inherent ability to measure absolute distances without mechanical compensation.
Low-cost miniature fiber-optic extrinsic Fabry-Perot interferometric pressure sensor for biomedical applications (2013)

A fiber-optic pressure sensor based in extrinsic Fabry-Perot interferometer (EFPI) is presented and discussed. The sensing probe is based on an inexpensive all-silica biocompatible design, with 0.2 mm outer diameter, suitable for disposable operation in medical catheters. A white-light interrogation system has been implemented, achieving a target accuracy of 1 mmHg and pressure stability of 1 mmHg/hour for long-term operation. A fiber Bragg grating (FBG) is added in proximity of the sensing tip, compensating temperature variations with 0.5°C accuracy. Design, simulation, and preliminary experimental validation are discussed.
Recombinant Canine Coronaviruses in Dogs, Europe (2009)

Coronaviruses of potential recombinant origin with porcine transmissible gastroenteritis virus (TGEV), referred to as a new subtype (IIb) of canine coronavirus (CCoV), were recently identified in dogs in Europe. To assess the distribution of the TGEV-like CCoV subtype, during 2001-2008 we tested fecal samples from dogs with gastroenteritis. Of 1,172 samples, 493 (42.06%) were positive for CCoV. CCoV-II was found in 218 samples, and CCoV-I and CCoV-II genotypes were found in 182. Approximately 20% of the samples with CCoV-II had the TGEV-like subtype; detection rates varied according to geographic origin. The highest and lowest rates of prevalence for CCoV-II infection were found in samples from Hungary and Greece (96.87% and 3.45%, respectively). Sequence and phylogenetic analyses showed that the CCoV-IIb strains were related to prototype TGEV-like strains in the 5' and the 3' ends of the spike protein gene.
Integrated inductors with magnetic materials for on-chip power conversion (2011)

This article consists of a collection of slides from the author's conference presentation on the deployment of integrated inductors with magnetic materials for on-chip power conversion. Some of the specific topics discussed include: the special features and processing capabilities of DC voltage converters; the properties of magnetic materials; and key features and processing capabilities of inductors.
Improved fit by asymmetric tibial prosthesis for total knee arthroplasty (1994)

The adequacy of the fit of the prosthesis to the tibia is an important variable in the outcome of total knee arthroplasty. A good fit covers the cancellous bone of both condyles, involves the denser bone of the tibial shell, but does not overhang beyond the bone at any point. In this research, an anatomically shaped tibial prosthetic base plate was developed from tibial measurements. A series of five template sizes, chosen to fit our patient database, was then evaluated for fit in the operating room by one surgeon. The assessment included bone exposure and the overhang of the prosthesis beyond the bone perimeter. The measurements of overhang or bone exposure were analysed. A commercial prosthesis was used as a control. An asymmetrical tibial plate conformed well to the anatomical shape of the resected upper tibia resulting in very little exposed bone and very few cases of overhang. The absence of such overhang provides better function in the surrounding stabilizing soft tissues, and so permits recovery of the maximum range of motion post-operatively.
ColumbuScout (2012)

In many database applications, search is still executed via form based query interfaces, which are then translated into SQL statements to find matching records. Ranking is usually not implemented unless users have explicitly indicated how to rank the matching records, e.g., in the ascending order of year. Often, this approach is neither intuitive nor user friendly (especially with many search fields in a query form). It also requires application developers to design schema-specific query forms and develop specific programs that understand these forms. In this work, we propose to demonstrate the ColumbuScout system that aims at quickly building and deploying a local search engine over one or more large databases. The ColumbuScout system adopts a search-engine-style approach for searches over local databases. It introduces its own indexing structures and storage designs, to improve its overall efficiency and scalability. We will demonstrate that it is simple for application developers to deploy ColumbuScout over any databases, and ColumbuScout is able to support search engine-like types of search over large databases efficiently and effectively.
Immunization with cytolethal distending toxin B produces autoantibodies to vinculin and small bowel bacterial changes in a rat model of postinfectious irritable bowel syndrome (2020)

Rats injected with CdtB developed a postinfectious IBS-like phenotype and autoimmunity to vinculin with corresponding reduction in intestinal vinculin expression.
IGF-I receptor protection from apoptosis in cells lacking the IRS proteins. (1997)

The type I insulin-like growth factor receptor (IGF-IR) plays a crucial role in cell growth, transformation and protection from apoptosis. Although the mitogenic function of the IGF-IR may require the activation of insulin receptor substrate-1 (IRS-1) or IRS-2, an overexpressed IGF-IR is able to protect 32D cells, which lack IRS-1 and IRS-2, from apoptosis caused by Interleukin-3 (IL-3) withdrawal. Here, using mutational analysis, the authors identify domains of the IGF-IR necessary to protect from apoptosis without downstream signaling from IRS-1 and IRS-2. A receptor mutant of the tyrosine kinase (TK) domain only partially inhibited antiapoptotic signaling, whereas a mutant displaying constitutive autophosphorylation of the receptor did not show enhanced survival activity. Surprisingly, survival signaling was dependent upon tyrosine 950, the binding site for IRS-1, IRS-2, and Shc proteins. Yet, overexpressed Shc and/or IRS-1 could not replace the IGF-IR survival signal, suggesting the existence of other critical substrates. Finally, the C-terminus may encode a proapoptotic signal, as receptors truncated at C-terminal residues 1229 or 1245 were found to inhibit apoptosis better than the wild type (WT) IGF-IR.
Brief Announcement (2018)

The infamous memory-processor bottleneck has motivated the search for logic-in-memory architectures. In this paper, we demonstrate how the transitive closure problem can be solved through in-memory computing within a 3D crosspoint memory. The proposed architecture requires only two layers of 1-diode 1-resistor (1D1R) interconnects and external feedback loops.