gebhart/patrepeval huggingface dataset:
A two-stage non-linear program for optimal electrical grid power balance under uncertainty (2011)

We propose a two-stage non-linear stochastic formulation for the economic dispatch problem under renewable-generation uncertainty. Each stage models dispatching and transmission decisions that are made on subsequent time periods. Certain generation decisions are made only in the first stage and the second stage realizes the actual renewable generation, where the uncertainty in renewable output is captured by a finite number of scenarios. Any resulting supply-demand mis-match must then be alleviated using extra, high marginal-cost power sources that can be tapped in short order. We propose two outer approximation algorithms to solve this nonconvex optimization problem to optimality. We show that under certain conditions the sequence of optimal solutions obtained under both alternatives has a limit point that is a globally-optimal solution to the original two-stage nonconvex program. Numerical experiments for a variety of parameter settings were carried out to indicate the efficiency and usability of this method of large practical instances.
Research on graphite reinforced glass matrix composites (1977)

The results of research for the origination of graphite-fiber reinforced glass matrix composites are presented. The method selected to form the composites consisted of pulling the graphite fiber through a slurry containing powdered glass, winding up the graphite fiber and the glass it picks up on a drum, drying, cutting into segments, loading the tape segment into a graphite die, and hot pressing. During the course of the work, composites were made with a variety of graphite fibers in a glass matrix.
Adaptive Off-Diagonal MIMO Pre-Coder (ODMP) for Downstream DSL Self FEXT Cancellation (2007)

This paper introduces a new family of per frequency linear pre-coders, called off-diagonal MIMO pre-coders (ODMP), for discrete multi-tone (DMT) based digital subscriber line (DSL) systems. ODMP target pre-compensation of the off- diagonal self far-end cross talk (FEXT) terms in the downstream DSL-MIMO channel matrix. We derive a low complexity and adaptive ODMP that simultaneously maximizes the Shannon Capacities per tone, experienced by the (non-cooperative) end-users. The updating scheme makes use of the error samples computed in each receiver. No matrix inversion is required in the algorithm which may be used for learning, tracking, and incrementing the ODMP without any disruption of data service. Finite precision simulation results reveal that coding the complex error with 16 bits allows for the algorithm to reach "self-FEXT free" performance after only 150 iterations in the learning phase and 450 iterations in the incrementing phase.
Enhanced PET resolution by combining pinhole collimation and coincidence detection (2015)

Spatial resolution of clinical PET scanners is limited by detector design and photon non-colinearity. Although dedicated small animal PET scanners using specialized high-resolution detectors have been developed, enhancing the spatial resolution of clinical PET scanners is of interest as a more available alternative. Multi-pinhole 511 keV SPECT is capable of high spatial resolution but requires heavily shielded collimators to avoid significant background counts. A practical approach with clinical PET detectors is to combine multi-pinhole collimation with coincidence detection. In this new hybrid modality, there are three locations associated with each event, namely those of the two detected photons and the pinhole aperture. These three locations over-determine the line of response and provide redundant information that is superior to coincidence detection or pinhole collimation alone. Multi-pinhole collimation provides high resolution and avoids non-colinearity error but is subject to collimator penetration and artifacts from overlapping projections. However the coincidence information, though at lower resolution, is valuable for determining whether the photon passed near a pinhole within the cone acceptance angle and for identifying through which pinhole the photon passed. This information allows most photons penetrating through the collimator to be rejected and avoids overlapping projections. With much improved event rejection, a collimator with minimal shielding may be used, and a lightweight add-on collimator for high resolution imaging is feasible for use with a clinical PET scanner. Monte Carlo simulations were performed of a (18)F hot rods phantom and a 54-pinhole unfocused whole-body mouse collimator with a clinical PET scanner. Based on coincidence information and pinhole geometry, events were accepted or rejected, and pinhole-specific crystal-map projections were generated. Tomographic images then were reconstructed using a conventional pinhole SPECT algorithm. Hot rods of 1.4 mm diameter were resolved easily in a simulated phantom. System sensitivity was 0.09% for a simulated 70-mm line source corresponding to the NEMA NU-4 mouse phantom. Higher resolution is expected with further optimization of pinhole design, and higher sensitivity is expected with a focused and denser pinhole configuration. The simulations demonstrate high spatial resolution and feasibility of small animal imaging with an add-on multi-pinhole collimator for a clinical PET scanner. Further work is needed to develop geometric calibration and quantitative data corrections and, eventually, to construct a prototype device and produce images with physical phantoms.
Mobile music modeling, analysis and recognition (2012)

We present an analysis of music modeling and recognition techniques in the context of mobile music matching, substantially improving on the techniques presented in [1]. We accomplish this by adapting the features specifically to this task, and by introducing new modeling techniques that enable using a corpus of noisy and channel-distorted data to improve mobile music recognition quality. We report the results of an extensive empirical investigation of the system's robustness under realistic channel effects and distortions. We show an improvement of recognition accuracy by explicit duration modeling of music phonemes and by integrating the expected noise environment into the training process. Finally, we propose the use of frame-to-phoneme alignment for high-level structure analysis of polyphonic music.
Coregistration of Angiogenesis Related Hemoglobin and Tissue Density in Breast Tumors Using Real-Time Opto-Acoustic Imaging Combined with Ultrasound. (2009)

Abstract BACKGROUNDThis study was performed to provide preliminary clinical feasibility for the characterization of breast tumors using a real-time dual modality laser opto-acoustic and ultrasound system to provide noninvasive characterization and differentiation of breast tumors based on the concentration of blood and its oxygen saturation in the tumor angiogenesis while also showing structure information based on traditional ultrasonic imaging methods. Opto-acoustic imaging uses pulses of laser light in the near-infrared spectral range to illuminate tissues and detects the resulting pressure with arrays of ultrawide-band ultrasonic transducers. After image reconstruction, tumor location, shape and dimensions are determined with a spatial resolution of better than 1 mm.MATERIALS and METHODSLaser illumination at the wavelength of 757 nm provides contrast based mainly on the hypoxic blood of breast carcinomas, while a wavelength of 1064 nm produces contrast dominated by the enhanced water content and normally oxygenated blood in benign fibroadenomas. Detection of the resulting ultrasonic signals with a commercial handheld ultrasound probe preserves quantitative information about the tumor optical absorption. Two opto-acoustic measurements yield solutions for the concentrations of hemoglobin and oxy-hemoglobin in pixels within the field of view. In the same location, ultrasonic images are generated to provide structure information. The optoacoustic information is displayed with the ultrasonic image to provide coregistered images containing structural and functional information.RESULTSInitial studies on 15 patients demonstrated that the combined opto-acoustic/ultrasound imaging system can detect areas of high optical absorption in the region of the tumors, confirmed with ultrasound, across varying tissue densities. Measurement and display of the optoacoustic signal amplitudes showed tumor brightness proportional to the optical absorption. Information obtained at two different wavelengths, one preferentially absorbed by hemoglobin (757 nm) and the other preferentially absorbed by oxyhemoglobin and water (1064 nm) provided noninvasive differentiation of breast carcinomas from benign tumors based upon differences in absorption in the region of the tumor.DISCUSSIONThe combination of optically-induced functional contrast and acoustically generated high resolution imaging in a novel breast cancer imaging modality demonstrated clinical feasibility and the potential for noninvasive diagnostics. Furthermore, coregistered ultrasonic and opto-acoustic images provide complimentary structural and functional images. This new imaging system is envisioned as an adjunct to X-ray mammography by providing ultrasonic imaging enhanced with functional information based on the optoacoustic spectroscopy. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5023.
Truncated ErbB2 Expressed in Tumor Cell Nuclei Contributes to Acquired Therapeutic Resistance to ErbB2 Kinase Inhibitors (2011)

ErbB2 tyrosine kinase inhibitors (TKI) block tyrosine autophosphorylation and activation of the full-length transmembrane ErbB2 receptor (p185(ErbB2)). In addition to p185(ErbB2), truncated forms of ErbB2 exist in breast cancer cell lines and clinical tumors. The contribution of these truncated forms, specifically those expressed in tumor cell nuclei, to the development of therapeutic resistance to ErbB2 TKIs has not been previously shown. Here, we show that expression of a 95-kDa tyrosine phosphorylated form of ErbB2, herein referred to as p95L (lapatinib-induced p95) was increased in ErbB2(+) breast cancer cells treated with potent ErbB2 TKIs (lapatinib, GW2974). Expressed in tumor cell nuclei, tyrosine phosphorylation of p95L was resistant to inhibition by ErbB2 TKIs. Furthermore, the expression of p95L was increased in ErbB2(+) breast cancer models of acquired therapeutic resistance to lapatinib that mimic the clinical setting. Pretreatment with proteasome inhibitors blocked p95L induction in response to ErbB2 TKIs, implicating the role of the proteasome in the regulation of p95L expression. In addition, tyrosine phosphorylated C-terminal fragments of ErbB2, generated by alternate initiation of translation and similar in molecular weight to p95L, were expressed in tumor cell nuclei, where they too were resistant to inhibition by ErbB2 TKIs. When expressed in the nuclei of lapatinib-sensitive ErbB2(+) breast cancer cells, truncated ErbB2 rendered cells resistant to lapatinib-induced apoptosis. Elucidating the function of nuclear, truncated forms of ErbB2, and developing therapeutic strategies to block their expression and/or activation may enhance the clinical efficacy of ErbB2 TKIs.
Positional Preferences of Ionizable Residues in Gly-X-YTriplets of the Collagen Triple-helix (1997)

Collagens contain a high amount of charged residues involved in triple-helix stability, fibril formation, and ligand binding. The contribution of charged residues to stability was analyzed utilizing a host-guest peptide system with a single Gly-X-Y triplet embedded within Ac(Gly-Pro-Hyp)3-Gly-X-Y-(Gly-Pro-Hyp)4-Gly-Gly-NH2. The ionizable residues Arg, Lys, Glu, and Asp were incorporated into the X position of Gly-X-Hyp; in the Y position of Gly-Pro-Y; or as pairs of oppositely charged residues occupying X and Y positions. The Gly-X-Hyp peptides had similar thermal stabilities, only marginally less stable than Gly-Pro-Hyp, whereas Gly-Pro-Y peptides showed a wide thermal stability range (Tm = 30-45 degrees C). The stability of peptides with oppositely charged residues in the X and Y positions appears to reflect simple additivity of the individual residues, except when X is occupied by a basic residue and Y = Asp. The side chains of Glu, Lys, and Arg have the potential to form hydrogen bonds with available peptide backbone carbonyl groups within the triple-helix, whereas the shorter Asp side chain does not. This may relate to the unique involvement of Asp residues in energetically favorable ion pair formation. These studies clarify the dependence of triple-helix stability on the identity, position, and ionization state of charged residues.
Licensed shared access &#x2014; State-of-the-art and current challenges (2014)

In the context of a wireless communication infrastructure, the Licensed Shared Access (LSA) concept is currently being developed by CEPT regulation and ETSI standardization bodies, with the aim of enabling cellular operators to have access to further spectral resources on a licensed shared basis. Even though spectrum owners, also known as Incumbents, will cooperate with cellular operators in the framework of a Sharing Agreement that is typically set-up for a long-term basis, the LSA concept will in addition, under specific conditions, give Incumbents the opportunity to reclaim spectrum on a per-need basis. Obviously, this new concept for managing spectrum introduces a number of novel challenges, such as vacate in a coordinated manner the LSA bands in case of a corresponding request being triggered by Incumbents, coordinate the LSA spectrum when it is used in proximity to neighbouring countries and/or regulation domains, establish protection zones in which maximum interference levels are guaranteed to Incumbents, etc. This paper gives an overview on the LSA state-of-the-art and elaborates the key challenges to be addressed in the future design of LSA systems.
Cytidine deaminase deficiency in tumor cells is associated with sensitivity to a naphthol derivative and a decrease in oncometabolite levels (2022)

Identifying new molecular targets for novel anticancer treatments is a major challenge in clinical cancer research. We have shown that cytidine deaminase (CDA) expression is downregulated in about 60% of cancer cells and tissues. In this study, we aimed to develop a new anticancer treatment specifically inhibiting the growth of CDA-deficient tumor cells. High-throughput screening of a chemical library led to the identification of a naphthol derivative, X55, targeting CDA-deficient tumor cells preferentially, without affecting the growth of non-tumoral cells regardless of CDA expression status. Metabolomic profiling revealed that CDA-deficient HeLa cells differed markedly from control HeLa cells. X55 treatment had a moderate effect on control cells, but greatly disturbed the metabolome of CDA-deficient HeLa cells, worsening the deregulation of many metabolites. In particular, the levels of the three oncometabolites, fumarate, succinate and 2-hydroxyglutarate, were significantly lower in CDA-depleted cells, and this decrease in levels was exacerbated by X55 treatment, revealing an unexpected link between CDA deficiency, mitochondrial function and X55 response. Finally, we identified strong downregulation of MAPT (encoding Tau, a microtubule associated protein) expression as a reliable predictive marker for tumor cell X55 sensitivity.
GIP receptor antagonism reverses obesity, insulin resistance, and associated metabolic disturbances induced in mice by prolonged consumption of high-fat diet (2007)

The gut hormone gastric inhibitory polypeptide (GIP) plays a key role in glucose homeostasis and lipid metabolism. This study investigated the effects of administration of a stable and specific GIP receptor antagonist, (Pro(3))GIP, in mice previously fed a high-fat diet for 160 days to induce obesity and related diabetes. Daily intraperitoneal injection of (Pro(3))GIP over 50 days significantly decreased body weight compared with saline-treated controls, with a modest increase in locomotor activity but no change of high-fat diet intake. Plasma glucose, glycated hemoglobin, and pancreatic insulin were restored to levels of chow-fed mice, and circulating triglyceride and cholesterol were significantly decreased. (Pro(3))GIP treatment also significantly decreased circulating glucagon and corticosterone, but concentrations of GLP-1, GIP, resistin, and adiponectin were unchanged. Adipose tissue mass, adipocyte hypertrophy, and deposition of triglyceride in liver and muscle were significantly decreased. These changes were accompanied by significant improvement of insulin sensitivity, meal tolerance, and normalization of glucose tolerance in (Pro(3))GIP-treated high-fat-fed mice. (Pro(3))GIP concentrations peaked rapidly and remained elevated 24 h after injection. These data indicate that GIP receptor antagonism using (Pro(3))GIP provides an effective means of countering obesity and related diabetes induced by consumption of a high-fat, energy-rich diet.
Object based video with progressive foreground (2002)

A novel algorithm is described for coding objects in video compression systems which gives complete control over the bit allocation to the video objects. The method is evaluated by application to a two layer codec, with background and foreground objects. Images in a sequence are divided into macroblocks, which are compared to a stored background model. Those whose mean square difference (MSD) exceeds a noise threshold are considered as foreground, and may be split into successively finer partitions described by a quadtree data structure. This defines more precisely the outline of the foreground object within each macroblock and gives a set of microblocks of variable size. The microblocks are transformed by the 2D DCT, and the DCT coefficients are coded bitplane by bitplane over the selected object using a zigzag masked (ZZM) technique. For robustness, data is then transmitted macroblock by macroblock, and intraframe or interframe coding of blocks can be selected adaptively at frame, macroblock or microblock level. The scheme is designed to stop sending bits when a certain bit allocation or PSNR is reached for any object, leading to fully controllable bit rates. The relationship between the average PSNR of the sequence and the average bits per pixel in a frame shows that the codec gives good performance over a range of peak bit rates from 0.1 bpp to 1 bpp. Over the whole range, the quality of the reconstructed sequence is significantly better than 'motion JPEG', while the codec is much simpler and faster than MPEG.
Microphone array speech enhancement in overdetermined signal scenarios (1993)

The problem of enhancing noisy speech by using a microphone array is considered. An algorithm called the graphic equalizer (GEQ) array is presented which trades off signal degradation for additional interference suppression. The algorithm is based on the concept of directly modifying the short-time spectral magnitude of the sum of the received signals. Simulation results are given that illustrate the advantages of using the GEQ array for diffuse-noise scenarios and for scenarios involving more interference signals than array degrees of freedom. The GEQ array was shown to outperform the Frost array for diffuse-noise and overdetermined signal scenarios, in which the Frost array was not capable of attenuating all of the interference with one broad null. While the GEQ array did not always yield a better SNR than the Frost array for these scenarios, it often outperformed the Frost array in terms of the power function spectral distance measure, a measure that is more highly correlated with human auditory perception than is the SNR.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
High-level design verification using Taylor Expansion Diagrams: first results (2003)

Recently a theory of a compact, canonical representation for arithmetic expressions, called Taylor Expansion Diagram (TED) has been proposed. This representation, based on a novel, non-binary decomposition principle, raises a level of design abstraction from bits to bit vectors and words, thus facilitating the verification of behavioral and RTL specifications of arithmetic designs. This paper presents the first practical results of using TED in the context of high-level design representation and verification. It discusses the use of TED for equivalence checking of behavioral and RTL designs and comments on its limitations. It also demonstrates the application of TEDs to verification of designs on an algorithmic level and comments on their potential use in high level synthesis.
TWO-PHASE PHOTOBIOLOGICAL ALGAL H 2-PRODUCTION SYSTEM (2000)

Continuous production of large volumes of H2 by algal cells has been achieved by depleting the cells of sulfur (Melis et al., 2000). The operation of this novel algal H2-production system occurs in the light with acetate-supplemented medium. Investigations are under way to simplify the system and determine the metabolic pathways involved in the process. Current year results include the observation that: (i) deple ion of nutrients other than sulfur will also inactivate O2 evolution but at slower rates, (ii) light and acetate are required for rapid inactivation of O2 evolution, suggesting an energy-dependent process, and (iii) inhibitors of Photosystem II also inhibit H2 evolution, indicating that residual water-oxidation activity is an important source of redu tant for H2 production. An automated photobioreactor experimental system was also developed at NREL. We report the design being used and the parameters found important to monitor sulfur deprivation. The automated system will be utilized in the future to measure the effect of a variety of parameters on the H2-evolution activity of sulfur-depleted cells.
An expendable penetrometer for rapid assessment of seafloor parameters (2002)

Information on the geoacoustic and geotechnical parameters of the seafloor under changing environmental conditions is important in sonar performance evaluation as well as in many engineering applications. Presently this knowledge is being gained through rather elaborate direct and/or remote measurements of sediment parameters. However, recently there has been an increase in the need for a simple system that can remotely measure some of these parameters from a moving ship or aircraft. The authors' work to date suggests that a freefall penetrometer, based on existing XBT technology and able to sense deceleration upon impact with the seafloor, would be a valuable tool in assessing these seafloor properties. When such a probe first impacts the bottom there is rapid deceleration controlled by the shear strength of the sediment, followed by a period of damped oscillation with frequency dependent on the geoacoustic properties of the sediment. By a complete analysis of the impact signature, including both the initial plastic penetration and the subsequent damped oscillation, the authors are able to make a first order classification of the sediment type, shear strength and geoacoustic properties which will be useful in a variety of different applications including sonar performance predictions, evaluation of off-shore foundation sites for drilling towers and other structures, and the assessment of bottom conditions relevant to dredging operations. At present a series of laboratory tests and field tests in the Baltic Sea and the Mediterranean are being carried out. Results of a portion of this work are presented in this paper.