gebhart/patrepeval huggingface dataset:
Passive millimeter-wave imaging (1993)

Millimeter-wave hardware systems are being developed. Our approach begins with identifying and defining the applications. System requirements are then specified based on mission needs using our end-to-end performance model. The model was benchmarked against existing data bases and, where data is deficient, it is acquired via field measurements. The derived system requirements are then validated with the appropriate field measurements using our imaging testbeds and hardware breadboards. The result is a final system that satisfies all the requirements of the target mission.
Characterizing perceptual artifacts in compressed video streams (2014)

To achieve optimal video quality under bandwidth and power constraints, modern video coding techniques employ lossy coding schemes, which often create compression artifacts that may lead to degradation of perceptual video quality. Understanding and quantifying such perceptual artifacts play important roles in the development of effective video compression, streaming and quality enhancement systems. Moreover, the characteristics of compression artifacts evolve over time due to the continuous adoption of novel coding structures and strategies during the development of new video compression standards. In this paper, we reexamine the perceptual artifacts created by standard video compression, summarizing commonly observed spatial and temporal perceptual distortions in compressed video, with emphasis on the perceptual temporal artifacts that have not been well identified or accounted for in previous studies. Furthermore, a floating effect detection method is proposed that not only detects the existence of floating, but also segments the spatial regions where floating occurs∗.
Naturally Occurring Resistance to Powdery Mildew in Seedlings of Cornus florida (1998)

Abstract Two production nursery fields of flowering dogwood, Cornus florida L ., seedlings with a high incidence of powdery mildew were surveyed for plants free of symptoms and signs of the disease. In greenhouse trials most of the seedlings selected in the field survey for being free of powdery mildew were found to be escapes (had no disease resistance) or to exhibit partial resistance (unacceptable low levels of resistance). In those trials, twenty seedlings, representing approximately 0.1% of the seedlings examined in the field surveys, displayed resistance to powdery mildew similar to that of C. florida ‘Cherokee Brave’. This group of disease resistant seedlings will be used to develop new cultivars of white flowering dogwood resistant to powdery mildew and to investigate the inheritance of powdery mildew resistance mechanisms in flowering dogwood.
Tile Pair-Based Adaptive Multi-Rate Stereo Shading (2018)

This work proposes a new stereo shading architecture that enables adaptive shading rates and automatic shading reuse among triangles and between two views. The proposed pipeline presents several novel features. First, the present sort-middle/bin shading is extended to tile pair-based shading to rasterize and shade pixels at two views simultaneously. A new rasterization algorithm utilizing epipolar geometry is then proposed to schedule tile pairs and perform rasterization at stereo views efficiently. Second, this work presents an adaptive multi-rate shading framework to compute shading on pixels at different rates. A novel tile-based screen space cache and a new cache reuse shader are proposed to perform such multi-rate shading across triangles and views. The results show that the newly proposed method outperforms the standard sort-middle shading and the state-of-the-art multi-rate shading by achieving considerably lower shading cost and memory bandwidth.
Separation Techniques for Carbon Nanotubes (2007)

Abstract Single‐walled carbon nanotubes have considerable potential as building blocks in future nanoscale electronics. The tubes exist in two modifications, metallic and semiconducting, which might be used in a range of electronic applications. One of the grand challenges is to separate metallic from semiconducting tubes in substantial quantities. In this respect, this article gives a brief overview over the separation techniques in this new field of nanotube research.
Optimized production of a biologically active Clostridium perfringens glycosyl hydrolase phage endolysin PlyCP41 in plants using virus-based systemic expression (2019)

We demonstrated that functionally active bacteriophage PlyCP41 endolysin can be produced in systemically infected plant tissue with potential for use of crude plant sap as an effective antimicrobial agent against C. perfringens.
Four-Gene Pan-African Blood Signature Predicts Progression to Tuberculosis (2018)

<b>Rationale:</b> Contacts of patients with tuberculosis (TB) constitute an important target population for preventive measures because they are at high risk of infection with <i>Mycobacterium tuberculosis</i> and progression to disease.<b>Objectives:</b> We investigated biosignatures with predictive ability for incident TB.<b>Methods:</b> In a case-control study nested within the Grand Challenges 6-74 longitudinal HIV-negative African cohort of exposed household contacts, we employed RNA sequencing, PCR, and the pair ratio algorithm in a training/test set approach. Overall, 79 progressors who developed TB between 3 and 24 months after diagnosis of index case and 328 matched nonprogressors who remained healthy during 24 months of follow-up were investigated.<b>Measurements and Main Results:</b> A four-transcript signature derived from samples in a South African and Gambian training set predicted progression up to two years before onset of disease in blinded test set samples from South Africa, the Gambia, and Ethiopia with little population-associated variability, and it was also validated in an external cohort of South African adolescents with latent <i>M. tuberculosis</i> infection. By contrast, published diagnostic or prognostic TB signatures were predicted in samples from some but not all three countries, indicating site-specific variability. <i>Post hoc</i> meta-analysis identified a single gene pair, <i>C1QC</i>/<i>TRAV27</i> (complement C1q C-chain / T-cell receptor-α variable gene 27) that would consistently predict TB progression in household contacts from multiple African sites but not in infected adolescents without known recent exposure events.<b>Conclusions:</b> Collectively, we developed a simple whole blood-based PCR test to predict TB in recently exposed household contacts from diverse African populations. This test has potential for implementation in national TB contact investigation programs.
The transferrin receptor expressed by gonococcal strain FA1090 is required for the experimental infection of human male volunteers (1998)

Iron, an essential nutrient for most microorganisms, is sequestered by the host to decrease the concentration of iron available to bacterial pathogens. Neisseria gonorrhoeae, the causative agent of gonorrhoea, can acquire iron by direct interaction with human iron-binding proteins, including the serum glycoprotein, transferrin. Iron internalization from host transferrin requires the expression of a bacterial receptor, which specifically recognizes the human form of transferrin. Two gonococcal transferrin-binding proteins have been implicated in transferrin receptor function, TbpA and TbpB. We constructed a gonococcal transferrin receptor mutant without the introduction of additional antibiotic resistance markers and tested its ability to cause experimental urethritis in human male volunteers. The transferrin receptor mutant was incapable of initiating urethritis, although the same inoculum size of the wild-type parent strain, FA1090, causes urethritis in >90% of inoculated volunteers. To our knowledge, this is the first experimental demonstration that a bacterial iron acquisition system is an essential virulence factor for human infection.
Methods for the Derivation and Use of Cardiomyocytes from Human Pluripotent Stem Cells (2011)

The availability of human cardiomyocytes derived from embryonic stem cells (ESCs) has generated -considerable excitement, as these cells are an excellent model system for studying myocardial development and may have eventual application in cell-based cardiac repair. Cardiomyocytes derived from the related induced pluripotent stem cells (iPSCs) have similar properties, but also offer the prospects of patient-specific disease modeling and cell therapies. Unfortunately, the methods by which cardiomyocytes have been historically generated from pluripotent stem cells are unreliable and typically result in preparations of low cardiac purity (typically <1% cardiomyocytes). We detail here the methods for a recently reported directed cardiac differentiation protocol, which involves the serial application of two growth factors known to be involved in early embryonic heart development, activin A, and bone morphogenetic protein-4 (BMP-4). This protocol reliably yields preparations of 30-60% cardiomyocytes, which can then be further enriched to >90% cardiomyocytes using straightforward physical methods.
Homogeneous nucleation of diamond powder in the gas phase (1989)

Homogeneous nucleation of diamond powder is reported. The experiments were performed in a low-pressure microwave-plasma reactor. The deposits were collected downstream of the reaction zone and subjected to wet oxidation to remove nondiamond carbons. The residues were analyzed by optical and electron microscopy, electron diffraction, and Raman spectroscopy. A variety of hydrocarbons diluted in argon, hydrogen, or oxygen gas mixtures were tested. In most cases only nondiamond materials, like graphite and carbyne, were obtained. Homogeneous nucleation of diamond was clearly observed in dichloromethane- and trichloroethylene-oxygen mixtures. The particles formed had crystalline shapes, mostly hexagonal. The largest particles were about 0.2 μm, although most of the particles were on the order of 50 nm in diameter. The powder was identified to be a mixture of polytypes of diamond.
Low-cost automated fiber pigtailing machine (2002)

Automated fiber pigtailing machines (AFPMs) have been designed and built under an ARPA-funded project The AFPM enables many of the critical technologies to perform automated sub-micron fiber pigtailing compatible with a low-cost manufacturing environment. These technologies include low-cost high-precision stages, computer vision to replace the labor-intensive coarse alignment, and many details of parts handling and feeding. Subsequent generations of the AFPM may build upon the design concepts developed here to pigtail fibers to OE devices in more complicated geometries. For example, all applications for this project use epoxy to attach the fibers, so no applications using solder or laser welding have been considered. Also, the stages to manipulate the fibers provide only three axes of translation, so no rotational degrees of freedom are available, including the very important roll axis for polarization-dependent applications. The third AFPM at LLNL will be used to develop some of these capabilities.
Application of nanosecond-pulsed dielectric barrier discharge on topographically non-uniform surfaces for biomedical treatment (2009)

Summary form only given. It has been demonstrated recently that direct treatment of relatively smooth surfaces by non-thermal dielectric barrier discharge (DBD) in air is highly effective in killing bacteria and fungi. The key aspect of the direct treatment was shown to be contact with electrical charges. These results hold significant promise for medical applications of direct DBD such as sterilization of wound surfaces. However, a typical DBD in air can be highly non-uniform, particularly on topographically non-uniform surfaces such as most of the living tissues. As a result, it is not clear that pathogens can be destroyed as effectively on the recessed areas between the ridges of real tissue by the conventional DBD in air. In this study authors have investigated effectiveness of a DBD excited by nanosecond rise and fall time voltage pulses in killing bacteria covering topographically non-uniform surfaces. Sterilization experiments were conducted on the E. coli covered agar surface acting as one of the DBD electrodes. The nanosecond-pulsed DBD (ns-DBD) was tested on non-uniform surfaces and produced uniform plasma independent of the surface topography. Sterilization effectiveness of ns-DBD also has been compared with that of a conventional DBD, i.e. microsecond-pulsed DBD (ms- DBD). Experiments reveal that the ns-DBD sterilizes a larger surface area than the ms-DBD does for the same duration and power. Moreover, experiments on non-uniform surfaces showed that the ns-DBD can penetrate into the recessed areas and sterilizes completely whereas the ms-DBD fails to do so. In summary, ns-DBD with short rise time and high overvoltage is insensitive to the morphological non-uniformities of the surface. Thus DBDs with nanosecond rise times are potentially more convenient for in vivo and hospital sterilization. Although several investigators did report uniform DBD systems, to the authors' knowledge the uniform discharge reported here is the only one to have been demonstrated at atmospheric pressure in open moist air over topographically non-uniform surfaces.
Non-destructive geometric and refractive index characterization of single and multi-element lenses using optical coherence tomography (2018)

Design of optical imaging systems requires careful balancing of lens aberrations to optimize the point-spread function (PSF) and minimize field distortions. Aberrations and distortions are a result of both lens geometry and glass material. While most lens manufacturers provide optical models to facilitate system-level simulation, these models are often not reflective of true system performance because of manufacturing tolerances. Optical design can be further confounded when achromatic or proprietary lenses are employed. Achromats are ubiquitous in systems that utilize broadband sources due to their superior performance in balancing chromatic aberrations. Similarly, proprietary lenses may be custom-designed for optimal performance, but lens models are generally not available. Optical coherence tomography (OCT) provides non-contact, depth-resolved imaging with high axial resolution and sensitivity. OCT has been previously used to measure the refractive index of unknown materials. In a homogenous sample, the group refractive index is obtained as the ratio between the measured optical and geometric thicknesses of the sample. In heterogenous samples, a method called focus-tracking (FT) quantifies the effect of focal shift introduced by the sample. This enables simultaneous measurement of the thickness and refractive index of intermediate sample layers. Here, we extend the mathematical framework of FT to spherical surfaces, and describe a method based on OCT and FT for full characterization of lens geometry and refractive index. Finally, we validate our characterization method on commercially available singlet and doublet lenses.
PCA-Based Spatially Adaptive Denoising of CFA Images for Single-Sensor Digital Cameras (2009)

Single-sensor digital color cameras use a process called color demosiacking to produce full color images from the data captured by a color filter array (CAF). The quality of demosiacked images is degraded due to the sensor noise introduced during the image acquisition process. The conventional solution to combating CFA sensor noise is demosiacking first, followed by a separate denoising processing. This strategy will generate many noise-caused color artifacts in the demosiacking process, which are hard to remove in the denoising process. Few denoising schemes that work directly on the CFA images have been presented because of the difficulties arisen from the red, green and blue interlaced mosaic pattern, yet a well-designed "denoising first and demosiacking later" scheme can have advantages such as less noise-caused color artifacts and cost-effective implementation. This paper presents a principle component analysis (PCA)-based spatially-adaptive denoising algorithm, which works directly on the CFA data using a supporting window to analyze the local image statistics. By exploiting the spatial and spectral correlations existing in the CFA image, the proposed method can effectively suppress noise while preserving color edges and details. Experiments using both simulated and real CFA images indicate that the proposed scheme outperforms many existing approaches, including those sophisticated demosiacking and denoising schemes, in terms of both objective measurement and visual evaluation.
Parallelizing and optimizing sparse tensor computations (2014)

Irregular computations over large-scale sparse data are prevalent in critical data applications and they have significant room for improvement on modern computer systems from the aspects of parallelism and data locality. We introduce new techniques to efficiently map large irregular computations with multi-dimensional sparse arrays (or sparse tensors) onto modern multi-core systems with non-uniform memory access (NUMA) behavior. We implement a static-cum-dynamic task scheduling scheme with low overhead for effective parallelization of sparse computations. We introduce locality-aware optimizations to the task scheduling mechanism that are driven by the sparse input data pattern. We evaluate our techniques on key sparse tensor decomposition methods that are widely used in areas such as data mining, graph analysis, and elsewhere. We achieve around 4-5x improvement in performance over existing parallel approaches and observe scalable parallel performance on modern multi-core systems with up to 32 processor cores.
Performance evaluation of a high-resolution parallel-plate differential mobility analyzer (2009)

Abstract. A high-resolution differential mobility analyzer (DMA), specially designed for (i) the measurement of ion mobility spectra, and (ii) the generation of a continuous stream of monomobile ions, has been developed and tested. The apparatus consists of two parallel-plate electrodes between which an electric field is applied. The test ion stream flows into the instrument through a narrow rectangular slit made in one of the electrodes, and migrates toward the other electrode driven by the applied field, while being transported by a stream of clean air which flows parallel to the plates at Reynolds number between 2×104 and 9×104 in laminar flow conditions. The collector electrode contains also a narrow slit through which ions of the desired mobility are withdrawn out of DMA. The classified ion current is measured with a high-sensitivity electrometer having a noise level around 0.1 fA. The theory behind the DMA operation is first discussed, focusing on the special case of parallel-plate geometry. Some generic results showing the stability and repeatability of the measurements and the resolving power of the instrument are presented next. The last part of the paper deals with the application of the apparatus to the study of the effect of humidity and aging time on the mobility spectra of air ions generated by a low-activity 241Am source.
Photonic True-Time-Delay Beamformer for a Phased Array Antenna Receiver based on Self-Heterodyne Detection (2016)

In this paper, we propose a novel photonic true-time delay beamforming system for a phased array antenna receiver. The beamformer relies on simple tunable optical delay lines and also on self-heterodyne coherent detection. Each tunable delay line is implemented by a Mach-Zehnder delay interferometer with tunable coupling ratio, which allows varying the delay from 0 up to the delay of the interferometer. Self-heterodyne coherent detection allows achieving maximum sensitivity inherent to coherent detection, and also laser phase noise cancellation, photonic RF phase shifting, and photonic RF frequency downconversion. The proposed system is analytically described and numerically validated. Numerical results show that, considering a beamsteering range of ±30°, the system is able to beamform the signals received by N antenna elements with negligible distortion, thereby proving to be very promising for high-end phased array antenna receivers operating at high RF frequencies.
Role of phosphorus as micro alloying element and its effect on corrosion characteristics of steel rebars in concrete environment (2022)

This communication reports the effect of phosphorus (P) added in micro concentration range in steel on kinetics, mechanism and growth of passive film in contact of chloride contaminated concrete. Electrochemical impedance spectroscopy, direct-current polarization, mass loss and Raman spectroscopic techniques were used to arrive at the findings. The results showed that an intentional addition of P in steel (0.064%) makes it more prone to uniform and localized corrosion (about 1.1 and 1.7 times) than the steel having low phosphorus (< 0.016%, present as tramp element) exposed under wet/dry conditions in simulated pore solution added with chloride and in the absence of this ion. A similar effect is also noted for the rebars embedded in mortars. Identification of corrosion products formed on steel rebars surface by Raman spectroscopy reveals thermodynamically stable maghemite and goethite phases on the surface of low P content steel. Unstable phase of lepidocrocite is recorded on the surface of higher phosphorus steel rebars. The findings are discussed with experimental evidence and taking clues from the published literature to arrive at plausible mechanism for this behaviour.
6 Biosynthesis of cannabis constituents (2023)

Cannabinoids, non-cannabinoid phenols, flavonoids, and terpenes are the major secondary metabolites of Cannabis sativa. Many enzymes and intermediates are involved in the process of biosynthesis of these metabolites. Oxidases, transferases, reductases, and isomerases are examples of these enzymes which are responsible for various chemical conversions of intermediates inside the plant's tissues. In this chapter, the biosynthesis of cannabinoids, non-cannabinoid phenols, flavonoids, and terpenes is discussed.
Fully Automated Sample Preparation for Ultrafast N-Glycosylation Analysis of Antibody Therapeutics (2015)

There is a growing demand in the biopharmaceutical industry for high-throughput, large-scale N-glycosylation profiling of therapeutic antibodies in all phases of product development, but especially during clone selection when hundreds of samples should be analyzed in a short period of time to assure their glycosylation-based biological activity. Our group has recently developed a magnetic bead-based protocol for N-glycosylation analysis of glycoproteins to alleviate the hard-to-automate centrifugation and vacuum-centrifugation steps of the currently used protocols. Glycan release, fluorophore labeling, and cleanup were all optimized, resulting in a <4 h magnetic bead-based process with excellent yield and good repeatability. This article demonstrates the next level of this work by automating all steps of the optimized magnetic bead-based protocol from endoglycosidase digestion, through fluorophore labeling and cleanup with high-throughput sample processing in 96-well plate format, using an automated laboratory workstation. Capillary electrophoresis analysis of the fluorophore-labeled glycans was also optimized for rapid (<3 min) separation to accommodate the high-throughput processing of the automated sample preparation workflow. Ultrafast N-glycosylation analyses of several commercially relevant antibody therapeutics are also shown and compared to their biosimilar counterparts, addressing the biological significance of the differences.