gebhart/patrepeval huggingface dataset:
Throughput-type pumps and ultrahigh vacuum (1994)

The development of ultrahigh-vacuum techniques had a profound effect on vacuum chamber design. It stimulated equally important improvements in pump design and in the understanding of some basic aspects of pump performance as well as their limitations. Design improvements also helped to clarify certain elusive concepts, for example, the meaning of the term ‘‘ultimate pressure’’ of a pump. Regarding partial pressures, the ordinary dual-stage sliding-vane mechanical pumps have been demonstrated to have full pumping speed at pressures as low as 10−10 Torr for gases nearly absent at the discharge. Modern vapor-jet pumps (diffusion pumps) appeared in the 1960’s with improvements in all performance aspects. Using high-performance pumping fluids, pressures near 1×10−9 Torr were achieved with only ambient temperature baffles, and near 1×10−11 Torr with liquid nitrogen cryobaffles. Even the extreme high-vacuum range was obtained with vapor-jet pumps assisted by gaseous helium- or liquid helium-cooled traps. However, the fear of accidental backstreaming events shifted the users to turbomolecular pumps which, after nearly 50 years of stagnation, finally became a major pumping choice. Turbopump improvements are continuing to this day driven by the need for cleaner pumping methods and rapid achievement of lower pressures. The trend is to optimized staging arrangements to increase the limiting pressure ratios (particularly for hydrogen), the introduction of light-weight, ceramic, grease-lubricated bearings, magnetic bearings, and at least ten times higher permissible discharge pressures which allow entirely oil-free backing pumps, the use of smaller backing pumps, and the achievement of an ultrahigh pressure range even in the presence of light gases such as hydrogen.
OPTIMUM FIELD ELEMENT SIZE FOR MAXIMUM YIELDS IN WINTER WHEAT, USING VARIABLE NITROGEN RATES (2001)

The resolution at which variability in soil test and yield parameters exist is fundamental to the efficient use of real-time sensor-based variable rate technology. This study was conducted to determine the optimum field element size for maximum yields in winter wheat (Triticum aestivum L.), using variable nitrogen (N) rates based on sensor readings. The effect of applying N at four different resolutions (0.84, 3.34, 13.38, and 53.51 m2) on grain yield, N uptake and efficiency of use was investigated at Haskell, Hennessey, Perkins, and Tipton, Oklahoma. At Feekes growth stage 5 an optical sensor developed at Oklahoma State University measured red (670 ± 6 nm) and near-infrared (NIR, 780 ± 6 nm) reflectance in each subplot. A normalized-difference-vegetative-index (NDVI) was calculated from the sensor measurements. Nitrogen was applied based on a NDVI–N rate calibration. Nitrogen rate, yield, N uptake, and efficiency of use responses to treatment resolution and applied N fertilizer differed in the 3 years of this experiment. In the first year, no significant influence of resolution on N rate, yield, N uptake, or efficiency of use was observed, likely a result of a late freeze that drastically reduced yields. In the second year of the experiment, there was a trend for a lower N rate and a higher efficiency of use for the 0.84 m2 resolution. In the third year of this study, there was a trend for a higher yield and a higher efficiency of use for the 53.51 m2 resolution at both sites. In general, the finer resolutions tended to have increased efficiency of use in high yielding environments (>2300 kg ha−1), and decreased yields in low yielding environments. This study indicates that application of prescribed fertilizer rates based on spatial variability at resolutions finer than 53.51 m2 could lead to increased yields, decreased grower costs, and decreased environmental impact of excess fertilizers.
A security framework for wireless mesh networks (2010)

Abstract The class of Wireless Mesh Networks (WMN) supports an ample set of applications including wireless community networks, radio access networks in rural or metropolitan areas, or wireless backbones for factory/process automation. Guaranteeing security is crucial for within these application scenarios. While contemporary wireless technologies, such as the IEEE 802.16 or the IEEE 802.11s standard, provide the basic protocol mechanisms for mesh networking, they lack in comprehensive security mechanisms. Additionally, novel security features of the above standards such as per‐link encryption break existing security solutions that rely on overhearing of the wireless channel. We close this gap by developing a holistic approach toward securing WMNs with particular focus on the network layer. We perform a threat analysis and then develop solutions (1) guaranteeing the integrity and authenticity of routing messages, (2) to locally and globally detect misbehavior of nodes in forwarding data or routing messages even for settings that do not allow for overhearing the channel, and (3) to dynamically manage reputation of nodes throughout the network. The combination of these building blocks enables to provide for secure, self‐organizing WMNs. As a proof‐of‐concept, we tailor and implement our solutions for the setting of a realistic IEEE 802.16 mesh network; we discuss the protection achieved and assess selected performance trade‐offs for the developed mechanisms. Copyright © 2010 John Wiley & Sons, Ltd.
Activity of n-propyl pyrazinoate against pyrazinamide-resistant Mycobacterium tuberculosis: investigations into mechanism of action of and mechanism of resistance to pyrazinamide (1995)

The mechanism of action of pyrazinamide (PZA) is not known. One hypothesis is that PZA functions as a prodrug of pyrazinoic acid. Susceptibility to PZA correlates with amidase activity of the Mycobacterium tuberculosis isolate in question. PZA-resistant isolates retain susceptibility in vitro to pyrazinoic acid and n-propyl pyrazinoate. Esters of pyrazinoic acid appear to circumvent the requirement for activation by mycobacterial amidase. The MICs of n-propyl pyrazinoate for M. tuberculosis isolates are lower than those of pyrazinoic acid. Further studies to assess the effects of modifications of the alcohol and pyrazine moieties of pyrazinoate esters on in vitro and in vivo antituberculosis activity are under way. This may lead to a candidate compound with enhanced activity against both PZA-susceptible and PZA-resistant M. tuberculosis isolates suitable for clinical development.
Lexicographic bit allocation for MPEG video coding (2002)

We consider the problem of allocating bits among pictures in an MPEG video coder to equalize the visual quality of the coded pictures, while meeting buffer and channel constraints imposed by the MPEG video buffering verifier We address this problem within a framework that consists of three components: (1) a bit production model for the input pictures, (2) a set of bit-rate constraints imposed by the video buffering verifier and (3) a novel lexicographic criterion for optimality. Under this framework, we derive simple necessary and sufficient conditions for optimality that lead to efficient algorithms.
Epitaxial (001) BiFeO3 membranes with substantially reduced fatigue and leakage (2008)

We report substantially reduced fatigue and electrical leakage in BiFeO3 membranes fabricated by releasing epitaxial (001) BiFeO3 films from the Si substrates on which they were grown. Fatigue-free switching behavior of up to 1010cycles was observed for BiFeO3 membranes with Pt top electrodes, while as-grown films break down at ∼109cycles. This is attributed to the low coercive field of BiFeO3 membranes and their being free from substrate clamping. In contrast, (111) BiFeO3 films exhibit significant fatigue at the same electric field. Epitaxial (001) BiFeO3 membranes with low coercive field are very promising for lead-free ferroelectric memory and magnetoelectric devices.
Dominant-negative mutations of platelet-derived growth factor (PDGF) receptors. Inhibition of receptor function by ligand-dependent formation of heterodimers between PDGF alpha- and beta-receptors. (1993)

We showed previously that a truncated form of the platelet-derived growth factor (PDGF) P-receptor lacking its kinase region can form a nonfunctional heterodimer with the wild-type P-receptor and thereby inhibit its signal transduction.In this paper we investigated whether the truncated form of either a-or P-receptor could block the function of the other type of wild-type PDGF receptor.When the truncated a-receptor was expressed in Xenopus oocytes in excess over either the wild-type a-or /.?-receptor, the Ca2+ mobilization signal elicited by either the wild-type a-or P-receptor was completely blocked.The truncated P-receptor abolished signaling by the wild-type a-receptor in response to PDGF-AB or -BB.However signal transduction by the a-receptor in response to PDGF-AA was not affected by the truncated P-receptor.In the presence of PDGF-AB or -BB, both the wild-type and truncated P-receptors formed a heterologous complex with the a-receptor in intact cells.A kinase-inactive P-receptor (an ATP-binding site mutation) became cross-phosphorylated on tyrosine residues by the co-expressed wild-type a-receptor in response to PDGF-AB or -BB but not in response to PDGF-AA.These findings indicate that the a-and p-receptors interact in response to PDGF-AB or -BB and are consistent with the hypothesis that the truncated a-receptor inhibits function of the wild-type P-receptor through formation of a ligand-dependent nonfunctional a@-heterodimer.A similar heterodimer can form between the truncated P-receptor and the wild-type a-receptor.These observations provide useful information for future studies using dominant-negative mutations of PDGF receptors to selectively inhibit the actions of specific PDGFs in animals. ~Platelet-derived growth factors (PDGFs)' are disulfidelinked dimers composed of two homologous but distinct polypeptides (PDGF-A and PDGF-B), which are encoded by different genes located on separate chromosomes (1, 2).Biologically active forms of all three combinations, PDGF-AA, PDGF-AB, and PDGF-BB, have been isolated from natural sources (3-5).RO-1 HL-32898 (to L. T. W.).
Transgenic Resistance to PVY<sup>O</sup> Associated with Post-Transcriptional Silencing of P1 Transgene Is Overcome by PVY<sup>N</sup> Strains That Carry Highly Homologous P1 Sequences and Recover Transgene Expression at Infection (2000)

Resistance to Potato virus Y (PVY) has been obtained in our previous studies through expression of the PVY P1 gene in sense or antisense orientation in potato cv. Pito. In the present study, the mechanism and strain specificity of the resistance were analyzed. Several features including low steady-state P1 mRNA expression in the resistant P1 plants indicated that resistance was based on post-transcriptional gene silencing (PTGS). Resistance was specific to PVY(O) isolates, the PVY strain group from which the P1 transgene was derived. However, according to group analyses, there was no distinguishing characteristic between the PVY(O) and PVY(N) strains P1 gene sequences. Therefore, the ability of the PVY(N) strains to overcome resistance could not be explained solely based on their P1 gene sequences. Infection with PVY(N) of the PVY(O)-resistant transgenic lines led to a recovery of expression of the P1 transgene. These data suggested that factors other than sequence homology are required in determination of the resistance specificity.
Biochemical characterization of salmon pancreas disease virus (2000)

Salmon pancreas disease virus (SPDV) has been shown to cause severe economic losses in farmed Atlantic salmon (Salmo salar) and has been reported to occur in Europe, Scandinavia and the United States. This paper describes the biochemical characterization of SPDV in terms of its RNA and protein composition. SPDV was purified by precipitation from infected Chinook salmon embryo (CHSE-214) cell-culture supernatant and sucrose density-gradient centrifugation. Fractions containing virus were identified by an immunodot blot assay using an SPDV-specific MAb. Two major proteins with molecular masses of approximately 55 and 50 kDa, putatively identified as the E1 and E2 alphavirus glycoproteins respectively, were detected when purified virus preparations were analysed by PAGE. Radiolabelling experiments indicated that SPDV infection of CHSE-214 cells did not shut-off host-cell protein synthesis, making attempts to identify virus-specific proteins unsuccessful. However, radioimmunoprecipitation assay (RIPA) experiments showed that two SPDV-specific MAbs reacted with a protein in the 50-55 kDa range. Northern blot hybridization with cloned cDNA probes indicated that infected cells contained RNA species of approximately 11.4 and 4 kb, which correspond to the genomic and subgenomic RNAs specified by SPDV. The results described are consistent with SPDV being characterized as an alphavirus.
Ratiometric Determination of Hg<sup>2+</sup> Ions Based on Simple Molecular Motifs of Pyrene and Dioxaoctanediamide (2007)

A new podand-type dioxaoctanediamide-based chemosensor having two pyrene moieties was prepared, and its fluoroionophoric behaviors toward transition-metal ions were investigated. Pyrene-appended dioxaoctanediamide 1 showed a selective fluorescence quenching toward Hg2+ ions over other transition-metal ions in an aqueous methanol solution. Unique responses in pyrene monomer and excimer emissions allowed selective ratiometric determination of Hg2+ ions in aqueous environments, and the detection limit was found to be 1.6 x 10(-6) M. [structure: see text]
Variable recovery time circuit for use with wide dynamic range automatic gain control for hearing aid (1993)

First Page
Development of a Prognostic Genetic Signature to Predict the Metastatic Risk Associated with Cutaneous Melanoma (2015)

The GEP signature accurately predicts metastasis risk in a multicenter cohort of primary cutaneous melanoma tumors. Preliminary Cox regression analysis indicates that the signature is an independent predictor of metastasis risk in the cohort presented.
Method and apparatus for seismic exploration using nonlinear sweeps (1985)

First Page
Constraints on variable bit-rate video for ATM networks (1992)

Constraints on the encoded bit rate of a video signal that are imposed by a channel and encoder and decoder buffers are considered. Conditions that ensure that the video encoder and decoder buffers do not overflow or underflow when the channel can transmit a variable bit rate are presented. Using these conditions and a commonly proposed network-user contract, the effect of a (BISDN) network policing function on the allowable variability in the encoded video bit rate is examined. It is shown how these ideas might be implemented in a system that controls both the encoded and transmitted bit rates. The performance of video that has been encoded using the derived constraints for the leaky bucket channel is presented.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
A portable surface plasmon resonance sensor system for real-time monitoring of small to large analytes (2005)

Many environmental applications exist for biosensors capable of providing real-time analyses. One pressing current need is monitoring for agents of chemical- and bio-terrorism. These applications require systems that can rapidly detect small organics including nerve agents, toxic proteins, viruses, spores and whole microbes. A second area of application is monitoring for environmental pollutants. Processing of grab samples through chemical laboratories requires significant time delays in the analyses, preventing the rapid mapping and cleanup of chemical spills. The current state of development of miniaturized, integrated surface plasmon resonance (SPR) sensor elements has allowed for the development of inexpensive, portable biosensor systems capable of the simultaneous analysis of multiple analytes. Most of the detection protocols make use of antibodies immobilized on the sensor surface. The Spreeta 2000 SPR biosensor elements manufactured by Texas Instruments provide three channels for each sensor element in the system. A temperature-controlled two-element system that monitors for six analytes is currently in use, and development of an eight element sensor system capable of monitoring up to 24 different analytes will be completed in the near future. Protein toxins can be directly detected and quantified in the low picomolar range. Elimination of false positives and increased sensitivity is provided by secondary antibodies with specificity for different target epitopes, and by sensor element redundancy. Inclusion of more than a single amplification step can push the sensitivity of toxic protein detection to femtomolar levels. The same types of direct detection and amplification protocols are used to monitor for viruses and whole bacteria or spores. Special protocols are required for the detection of small molecules. Either a competition type assay where the presence of analyte inhibits the binding of antibodies to surface-immobilized analyte, or a displacement assay, where antibodies bound to analyte on the sensor surface are displaced by free analyte, can be used. The small molecule detection assays vary in sensitivity from the low micromolar range to the high picomolar.
Demo (2011)

In this demo we present a novel ranging based on Time Of Flight (TOF) measurements for Wireless LAN (WLAN) and demonstrate the tracking capability of the distance from a WLAN Access Point (AP) to a WLAN mobile device. Conference participants can move with the mobile device around the coverage range of the AP to observe both the accuracy and the convergence of distance tracking. Using our software-based prototype implementation, we achieve accuracies of few meters at a walking speed and in different channel conditions.
Cloning, sequence and expression of the gene encoding the malolactic enzyme from <i>Lactococcus</i><i>lactis</i> (1993)

Many lactic acid bacteria can carry out malolactic fermentation. This secondary fermentation is mediated by the NAD- and Mn(2+)-dependent malolactic enzyme, which catalyses the decarboxylation of L-malate to L-lactate. The gene we call mleS, coding for malolactic enzyme, was isolated from Lactococcus lactis. The mleS gene consists of one open reading frame capable of coding for a protein with a calculated molecular mass of 59 kDa. The amino acid sequence of the predicted MleS gene product is homologous to the sequences of different malic enzymes. Bacterial and yeast cells expressing the malolactic gene convert L-malate to L-lactate.
Particulate rubber modified nylon 6 RIM (1988)

Nylon 6 produced by the reaction injection molding (RIM) process is toughened through block copolymerization of caprolactam with functional, rubbery prepolymers. This article describes an alternate route, where caprolactam is polymerized in the presence of a dispersed particulate rubber. The particulate rubber employed in this study has a core-shell morphology with a soft, crosslinked butadiene-based rubbery core and a grafted styrene–acrylonitrile shell. The core-shell rubber is dispersed as a latex in caprolactam to high quality dispersions which, on anionic polymerization, give tough castings. Incorporation of a reactive monomer such as hydroxypropyl methacrylate in the graft shell brings about further improvement in impact strength.
Intracranial Vessel Wall MRI: Principles and Expert Consensus Recommendations of the American Society of Neuroradiology (2016)

Intracranial vessel wall MR imaging is an adjunct to conventional angiographic imaging with CTA, MRA, or DSA. The technique has multiple potential uses in the context of ischemic stroke and intracranial hemorrhage. There remain gaps in our understanding of intracranial vessel wall MR imaging findings and research is ongoing, but the technique is already used on a clinical basis at many centers. This article, on behalf of the Vessel Wall Imaging Study Group of the American Society of Neuroradiology, provides expert consensus recommendations for current clinical practice.
Hyaluronic Acid-Binding Scaffold for Articular Cartilage Repair (2012)

Hyaluronic acid (HA) is an extracellular matrix molecule with multiple physical and biological functions found in many tissues, including cartilage. HA has been incorporated in a number of biomaterial and scaffold systems. However, HA in the material may be difficult to control if it is not chemically modified and chemical modification of HA may negatively impact biological function. In this study, we developed a poly(ethylene glycol) hydrogel with noncovalent HA-binding capabilities and evaluated its ability to support cartilage formation in vitro and in an articular defect model. Chondrogenic differentiation of mesenchymal stem cells encapsulated in the HA-interactive scaffolds containing various amounts of exogenous HA was evaluated. The HA-binding hydrogel without exogenous HA produced the best cartilage as determined by biochemical content (glysocaminoglycan and collagen), histology (Safranin O and type II collagen staining), and gene expression analysis for aggrecan, type I collagen, type II collagen, and sox-9. This HA-binding formulation was then translated to an osteochondral defect model in the rat knee. After 6 weeks, histological analysis demonstrated improved cartilage tissue production in defects treated with the HA-interactive hydrogel compared to noninteractive control scaffolds and untreated defects. In addition to the tissue repair in the defect space, the Safranin O staining in cartilage tissue surrounding the defect was greater in treatment groups where the HA-binding scaffold was applied. In sum, incorporation of a noncovalent HA-binding functionality into biomaterials provides an ability to interact with local or exogenous HA, which can then impact tissue remodeling and ultimately new tissue production.
A Method for Signal Leakage Cancellation in Multistatic Subsurface SAR Imaging System (2022)

Multi-static subsurface synthetic aperture radar (SAR) is a promising tool capable of providing 3-D high resolution images of targets buried underground. The high detection capability of the system stems from the fact that the multi-static configuration allows for viewing the targets from many directions. However, a primal limiting factor for such configuration is the dominance of the direct and ground reflection signals over the scattered target signal hindering the system sensitivity. This letter presents a simple technique to overcome such drawback. By an appropriate utilization of SAR data, each adjacent sampling points are co-processed together as a two-element array in such a way as to have a null along the direction of the direct and ground reflection signals suppressing such signals and making the target signals more discernible. The technique is described in details and the potential problems arising from array processing are discussed. Additionally, a modified version of back projection imaging algorithm suitable for the array is provided. The performance of the proposed technique is assessed by simulation data of buried metallic spheres as well as measurement data for a buried metallic pipeline. Both simulation and measurements show a significant improvement in target detection and image quality.