gebhart/patrepeval huggingface dataset:
Terahertz microfluidic sensor based on a parallel-plate waveguide resonant cavity (2009)

We describe a terahertz optical resonator that is ideally suited for highly sensitive and noninvasive refractive-index monitoring. The resonator is formed by machining a rectangular groove into one plate of a parallel-plate waveguide, and is excited using the lowest-order transverse-electric (TE1) waveguide mode. Since the resonator can act as a channel for fluid flow, it can be easily integrated into a microfluidics platform for real-time monitoring. Using this resonator with only a few microliters of liquid, we demonstrate a refractive-index sensitivity of 3.7×105 nm/refractive-index-unit, the highest ever reported in any frequency range.
Enhanced production of protease by <i>Pseudoalteromonas arctica</i> PAMC 21717 via statistical optimization of mineral components and fed-batch fermentation (2015)

The objective of this study was to statistically optimize the mineral components of the nutritional medium required for enhancing the production of a cold-active extracellular serine-type protease, W-Pro21717, by the Antarctic bacterium Pseudoalteromonas arctica PAMC 21717. Skim milk was identified as the major efficient inducer. Among the 12 components included in the unoptimized medium, skim milk, NaCl, Na2SO4, Fe(C6H5O7) (ferric citrate), and KCl were determined, by the Plackett-Burman and Box-Behnken design, to have a major effect on W-Pro21717 production. Fed-batch fermentation (5 L scale) using the mineral-optimized medium supplemented with concentrated skim milk (critical medium component) resulted in a W-Pro21717 activity of 53.4 U/L, a 15-fold increment in production over that obtained using unoptimized flask culture conditions. These findings could be applied to scale up the production of cold-active protease.
Spurious free time-to-digital conversion in an ADPLL using short dithering sequences (2010)

This paper proposes an enhancement of the digital phase detection mechanism in an all-digital phase locked loop (ADPLL) operable at multi-GHz by randomization of the reference frequency phase by carefully chosen dither sequences. This renders the digital phase detector in ADPLL free from any phase domain spurious tones as a consequence of ill-conditioned sampling of variable oscillator phase in the time-to-digital converter (TDC). TDC has a typical time quantization in the range of 5 to 30 ps using modern deep sub-micron technologies. This finite dead-band can result in spurious tones, whenever an “integer” relationship arises between the oscillator phase and the TDC sampling process. This anomaly can be resolved using carefully selected spectrum-friendly dithering mechanisms. This work proposes injection of a short sequence dither signal into the reference signal to overcome the quantization introduced limit-cycles. This results in a robust phase tracking and spurious free operation of the ADPLL.
Cell-Mediated Immunity Generated in Response to a Purified Inactivated Vaccine for Dengue Virus Type 1 (2020)

Dengue is the most prevalent arboviral disease afflicting humans, and a vaccine appears to be the most rational means of control. Dengue vaccine development is in a critical phase, with the first vaccine licensed in some countries where dengue is endemic but demonstrating insufficient efficacy in immunologically naive populations. Since virus-neutralizing antibodies do not invariably correlate with vaccine efficacy, other markers that may predict protection, including cell-mediated immunity, are urgently needed. Previously, the Walter Reed Army Institute of Research developed a monovalent purified inactivated virus (PIV) vaccine candidate against dengue virus serotype 1 (DENV-1) adjuvanted with alum. The PIV vaccine was safe and immunogenic in a phase I dose escalation trial in healthy, flavivirus-naive adults in the United States. From that trial, peripheral blood mononuclear cells obtained at various time points pre- and postvaccination were used to measure DENV-1-specific T cell responses. After vaccination, a predominant CD4<sup>+</sup> T cell-mediated response to peptide pools covering the DENV-1 structural proteins was observed. Over half (13/20) of the subjects produced interleukin-2 (IL-2) in response to DENV peptides, and the majority (17/20) demonstrated peptide-specific CD4<sup>+</sup> T cell proliferation. In addition, analysis of postvaccination cell culture supernatants demonstrated an increased rate of production of cytokines, including gamma interferon (IFN-γ), IL-5, and granulocyte-macrophage colony-stimulating factor (GM-CSF). Overall, the vaccine was found to have elicited DENV-specific CD4<sup>+</sup> T cell responses as measured by enzyme-linked immunosorbent spot (ELISpot), intracellular cytokine staining (ICS), lymphocyte proliferation, and cytokine production assays. Thus, together with antibody readouts, the use of a multifaceted measurement of cell-mediated immune responses after vaccination is a useful strategy for more comprehensively characterizing immunity generated by dengue vaccines.<b>IMPORTANCE</b> Dengue is a tropical disease transmitted by mosquitoes, and nearly half of the world's population lives in areas where individuals are at risk of infection. Several vaccines for dengue are in development, including one which was recently licensed in several countries, although its utility is limited to people who have already been infected with one of the four dengue viruses. One major hurdle to understanding whether a dengue vaccine will work for everyone-before exposure-is the necessity of knowing which marker can be measured in the blood to signal that the individual has protective immunity. This report describes an approach measuring multiple different parts of immunity in order to characterize which signals one candidate vaccine imparted to a small number of human volunteers. This approach was designed to be able to be applied to any dengue vaccine study so that the data can be compared and used to inform future vaccine design and/or optimization strategies.
Automatic corpus callosum segmentation for standardized MR brain scanning (2007)

Magnetic Resonance (MR) brain scanning is often planned manually with the goal of aligning the imaging plane with key anatomic landmarks. The planning is time-consuming and subject to inter- and intra- operator variability. An automatic and standardized planning of brain scans is highly useful for clinical applications, and for maximum utility should work on patients of all ages. In this study, we propose a method for fully automatic planning that utilizes the landmarks from two orthogonal images to define the geometry of the third scanning plane. The corpus callosum (CC) is segmented in sagittal images by an active shape model (ASM), and the result is further improved by weighting the boundary movement with confidence scores and incorporating region based refinement. Based on the extracted contour of the CC, several important landmarks are located and then combined with landmarks from the coronal or transverse plane to define the geometry of the third plane. Our automatic method is tested on 54 MR images from 24 patients and 3 healthy volunteers, with ages ranging from 4 months to 70 years old. The average accuracy with respect to two manually labeled points on the CC is 3.54 mm and 4.19 mm, and differed by an average of 2.48 degrees from the orientation of the line connecting them, demonstrating that our method is sufficiently accurate for clinical use.
Enantioselective Synthesis of a Dual Orexin Receptor Antagonist (2012)

A concise, enantioselective synthesis of the potent dual orexin inhibitor suvorexant (1) is reported. Key features of the synthesis include a mild copper-catalyzed amination, a highly chemoselective conjugate addition, and a tandem enantioselective transamination/seven-membered ring annulation. The synthesis requires inexpensive starting materials and only four linear steps for completion.
Liver Progenitor Cell Line HepaRG Differentiated in a Bioartificial Liver Effectively Supplies Liver Support to Rats with Acute Liver Failure (2012)

A major roadblock to the application of bioartificial livers is the need for a human liver cell line that displays a high and broad level of hepatic functionality. The human bipotent liver progenitor cell line HepaRG is a promising candidate in this respect, for its potential to differentiate into hepatocytes and bile duct cells. Metabolism and synthesis of HepaRG monolayer cultures is relatively high and their drug metabolism can be enhanced upon treatment with 2% dimethyl sulfoxide (DMSO). However, their potential for bioartificial liver application has not been assessed so far. Therefore, HepaRG cells were cultured in the Academic Medical Center bioartificial liver (AMC-BAL) with and without DMSO and assessed for their hepatic functionality in vitro and in a rat model of acute liver failure. HepaRG-AMC-BALs cultured without DMSO eliminated ammonia and lactate, and produced apolipoprotein A-1 at rates comparable to freshly isolated hepatocytes. Cytochrome P450 3A4 transcript levels and activity were high with 88% and 37%, respectively, of the level of hepatocytes. DMSO treatment of HepaRG-AMC-BALs reduced the cell population and the abovementioned functions drastically. Therefore, solely HepaRG-AMC-BALs cultured without DMSO were tested for efficacy in rats with acute liver failure (n = 6). HepaRG-AMC-BAL treatment increased survival time of acute liver failure rats ∼50% compared to acellular-BAL treatment. Moreover, HepaRG-AMC-BAL treatment decreased the progression of hepatic encephalopathy, kidney failure, and ammonia accumulation. These results demonstrate that the HepaRG-AMC-BAL is a promising bioartificial liver for clinical application.
Production and electrical characterization of the reflectin A2 isoform from Doryteuthis (Loligo) pealeii (2016)

​We report an improved methodology for the production of cephalopod proteins known as reflectins. Our findings may afford new opportunities for the study of these proteins’ multifaceted materials properties.
Digital multiphase modulator — A power D/A perspective (2006)

A new architecture is proposed for digital multiphase modulators that leads to a natural hardware efficient realization without compromise in hardware or performance. The combined modulator, switching phases and output filter are viewed as a digital to analog converter with high power output, or a “power D/A”. The duty cycle command bits are separated into high resolution and low resolution bits, where the low resolution bits directly control the number of converter phases that are on at a given time. Hardware efficiency is achieved by using only a single high resolution block that is time shared among all phases and a simple low resolution block that uses a single counter to track appropriate phasing of the outputs. Relatively little digital logic is required to combine the outputs of the two modules, resulting in an efficient design that scales easily with a large number of phases without requiring significant additional hardware per phase. The duty cycle command is updated at the fast rate of n times the single phase switching frequency, where n is the number of phases. The approach is experimentally verified in a 16 phase system operating at 1.5 MHz per phase with 9 bits (1.3 ns) of PWM resolution.
Volumetric imaging using single chip integrated CMUT-on-CMOS IVUS array (2012)

An intravascular ultrasound (IVUS) catheter that can provide forward viewing volumetric ultrasound images would be an invaluable clinical tool for guiding interventions. Single chip integration of front-end electronics with capacitive micromachined ultrasonic transducers (CMUTs) is highly desirable to reduce the interconnection complexity and enable miniaturization in IVUS catheters. For this purpose we use the monolithic CMUT-on-CMOS integration where CMUTs are fabricated directly on top of pre-processed CMOS wafers. This minimizes parasitic capacitances associated with connection lines. We have recently implemented a system design including all the required electronics using 0.35-µm CMOS process integrated with a 1.4-mm diameter CMUT array. In this study, we present the experimental volumetric imaging results from an ex-vivo chicken heart phantom. The imaging results demonstrate that the single-chip forward looking IVUS (FL-IVUS) system with monolithically integrated electronics has potential to visualize the front view of coronary arteries.
Chemical synthesis of the organoarsenical antibiotic arsinothricin (2021)

We report two routes of chemical synthesis of arsinothricin (AST), the novel organoarsenical antibiotic. One is by condensation of the 2-chloroethyl(methyl)arsinic acid with acetamidomalonate, and the second involves reduction of the <i>N</i>-acetyl protected derivative of hydroxyarsinothricin (AST-OH) and subsequent methylation of a trivalent arsenic intermediate with methyl iodide. The enzyme AST <i>N</i>-acetyltransferase (ArsN1) was utilized to purify l-AST from racemic AST. This chemical synthesis provides a source of this novel antibiotic for future drug development.
Micro hollow cathode discharges (1995)

Summary form only given, as follows. Hollow cathode discharges are glow discharges with the cathode fall and negative glow confined in a cavity in the cathode. For the discharge to develop the cathode hole dimensions must be on the order of the mean free path. By reducing the cathode hole dimensions it is therefore possible to increase the pressure. Stable hollow cathode discharges in air have been observed at almost one atmosphere when the cathode diameter was reduced to 20 micrometers. In order to study the electrical parameters of a micro hollow cathode discharge, a set of experiments has been performed in argon at pressures in the torr range and a cathode hole diameter of 0.7 mm in molybdenum. The current-voltage characteristics and the appearance of the discharge plasma showed two distinct regions. At lower voltage or pressure the current varies linearly with voltage and the hollow cathode plasma is concentrated around the axis of the cathode hole (low glow mode). At higher values of voltage or pressure the current increases nonlinearly, up to a point where a transition into a low voltage hollow cathode arc was observed, and the plasma column expands and fills almost the entire cathode hole (high glow mode). Spectral measurements showed that the transition from the low glow mode into the high glow mode is related to an increased density of electrode vapor in the hollow cathode discharge. Up to the breakdown into a hollow cathode arc, the current voltage characteristic of the discharge has a positive slope. In this range, hollow cathode discharges can be operated in parallel without a ballast resistor.
Smooth Beamforming and Efficient Beamforming Weight Computation (2007)

This paper investigates an efficient way of computing the beamforming weights for a MIMO OFDM system. It is shown that computing the weights incrementally across correlated channels can significantly reduce the complexity. An additional benefit of this technique is that it provides a "smooth" beamformer, i.e., it does not significantly change the correlation of the beamformed channel, which makes it suitable for advanced channel estimation techniques. We evaluate its performance in the OFDM-based IEEE802.11n system, where the computations are done across the subcarriers, and show that significant gains from channel smoothing at the receiver are possible due to the smooth beamformer. We also show that linear interpolation of beamforming matrices between subcarriers can be used, which only has a small degradation compared to optimal interpolation but a much simple implementation.
Segmentation of Multimedia Streams for Proxy Caching (2004)

Proxy caching of large multimedia objects on the edge of the Internet has become increasingly important for reducing network latency. For a large media object, such as a two-hour video, treating the whole media as a single object for caching is not appropriate. In this paper, we study three media segmentation approaches to proxy caching: fixed, pyramid, and skyscraper. Blocks of a media stream are grouped into various segments for cache management. The cache admission and replacement policies attach different caching priorities to individual segments, taking into account the access frequency of the media object and the segment distance from the start of the media. These caching policies give preferential treatment to the beginning segments. As such, most user requests can be quickly played back from the proxy servers without delay. Event-driven simulations are conducted to evaluate the segmentation approaches and compare them with whole media caching. The results show that: 1) compared with whole media caching, segmentation-based caching is more effective not only in increased byte-hit ratio but also in lowered fraction of requests that requires delayed start; 2) pyramid segmentation, where segment size increases exponentially, is the best segmentation approach; and 3) segmentation-based caching is especially advantageous when the cache size is limited, when the set of hot media objects changes over time, when the media file size is large, and when there are a large number of distinct media objects.
Transport properties and valence band feature of high-performance (GeTe)<sub>85</sub>(AgSbTe<sub>2</sub>)<sub>15</sub>thermoelectric materials (2014)

This paper aims at elucidating the origin of the high thermoelectric power factor of p-type (AgxSbTe_(x/2+1.5)15)(GeTe)_(85) (TAGS) thermoelectric materials with 0.4 ≤ x ≤ 1.2. All samples exhibit good thermoelectric figures of merit (zT) which reach 1.5 at 700 K for x = 0.6. Thermoelectric and thermomagnetic transport properties (electrical resistivity, Seebeck, Hall and transverse Nernst–Ettinghausen coefficients) are measured and used to calculate the scattering factor, the Fermi energy, the density-of-states (DOS) effective mass and hole mean free path (mfp). The DOS effective mass is very high due to the large band mass of the primary valence band and the high degeneracy of pockets in the Fermi surface from the second valence band. The highly degenerate Fermi surface increased the total DOS without decreasing mobility, which is more desirable than the high DOS that comes from a single carrier pocket. The high-temperature hole mfp approaches the Ioffe–Regel limit for band-type conduction, which validates our discussion based on band transport and is also important for TAGS alloys having high zT with heavy bands. The present results show that multiple degenerate Fermi surface pockets provide an effective way of substantially increasing the power factor of thermoelectric materials with low thermal conductivity.
Monolithic double-grating phase mask for high-spatial-coherence large-period grating printing (2009)

A monolithic double-grating phase mask comprising three short-pitch grating sections of spatial frequencies k1 and k2 collocated at one side of a substrate produces a large-period interferogram without higher harmonics to print in a photoresist film a latent grating of small spatial frequency equal to twice k2−k1. When incorporated in a write-on-the-fly scheme, the elements permit the fabrication of unlimitedly long gratings.
Soliton mode-locked miniature Nd:YVO4 laser with 77 GHz repetition rate (2001)

We present a miniature Nd:YVO4 laser which is passively mode-locked up to ~ 77 GHz repetition rate, using a semiconductor saturable absorber mirror (SESAM). We achieved 65 mW output power with 2.7 ps long soliton pulses.
Nanoscale engineering of photoelectron processes by charging quantum dots (2012)

Novel approach to control of photoelectron processes is based on nanoscale engineering of 3D potential profile employing quantum dots with built-in charge (Q-BIC). Charging of quantum dots creates local potential barriers around single dots, if dots are arbitrary distributed in the medium, and collective barriers around dot clusters, rows etc, if quantum dots form specific structures. Manipulations with potential barriers provide an effective tool for suppression of fast capture processes of photocarriers by quantum dots. This allows one to increase the photocarrier lifetime and to reduce the recombination losses. The charging of dots also enhances the electron coupling to infrared radiation and multi-step absorption of sub-gap photons. Q-BIC nanomaterials have a number of attractive features to be used in photovoltaic and sensing applications.
Optimal strategies for testing nondeterministic systems (2004)

This paper deals with testing of nondeterministic software systems. We assume that a model of the nondeterministic system is given by a directed graph with two kind of vertices: states and choice points. Choice points represent the nondeterministic behaviour of the implementation under test (IUT). Edges represent transitions. They have costs and probabilities. Test case generation in this setting amounts to generation of a game strategy. The two players are the testing tool (TT) and the IUT. The game explores the graph. The TT leads the IUT by selecting an edge at the state vertices. At the choice points the control goes to the IUT. A game strategy decides which edge should be taken by the TT in each state. This paper presents three novel algorithms 1) to determine an optimal strategy for the bounded reachability game, where optimality means maximizing the probability to reach any of the given final states from a given start state while at the same time minimizing the costs of traversal; 2) to determine a winning strategy for the bounded reachability game, which guarantees that given final vertices are reached, regardless how the IUT reacts; 3) to determine a fast converging edge covering strategy, which guarantees that the probability to cover all edges quickly converges to 1 if TT follows the strategy.
A novel, nested, multiplex, real-time PCR for detection of bacteria and fungi in blood (2014)

Results obtained by us indicated that the designed PCR methods: (1) allow to detect bacteria in whole blood samples, (2) are much more sensitive than culture method, (3) allow differentiation of the main groups of microorganisms within a few hours.
A Furnace Wall Ash Monitoring System for Coal Fired Boilers (1981)

This paper describes the successful development of an ash-deposit monitoring system for use in large pulverized-coal fired boilers. Using commercially proven heat flux meters the system measures the severity of ash deposition by measuring the net decrease in heat flux through the boiler walls. Testing of a prototype in two Canadian Utility boilers burning Western coals has shown that the system gives a reliable measure of the cleanliness of furnace walls and of the effectiveness (or failure) of soot blowers to remove deposits. Indications are that the system will be valuable in improving efficiency of boiler operations and in minimizing slagging and fouling problems when firing difficult coals.