gebhart/patrepeval huggingface dataset:
Pulsed RF Circuits for Ultra Wideband Communications and Radar Applications (2011)

This thesis explores the design of fast-settling pulse generators and pulsed low noise amplifiers (LNAs) for Ultra-Wideband (UWB) applications.These components are critical in pulsed UWB transceivers, and a high energy efficiency is sought without adversely affecting RF performance and functionality.To this end, new pulse generators with a subnanosecond settling time and a low energy consumption of only a few picojoules per pulse are targeted.Moreover, a novel pulsed LNA is investigated for a low power consumption that can be scaled with the duty cycle.First, an energy-efficient tunable pulse generator is proposed for high-data-rate 3.1-10.6GHz UWB applications.A current-starved ring oscillator is quickly switched on and off, and the amplitude envelope is shaped using a passive attenuator.The energy consumption per pulse is below 4.2 pJ while the pulse amplitude is 150 mV, yielding a high energy efficiency.A quadrature pulse generator is then presented for 22-29 GHz UWB applications with a settling time below 0.5 ns.An inductor-capacitor (LC) oscillator is quickly switched on and off with a new technique, and the amplitude envelope is shaped using a variable passive attenuator.The energy consumption per pulse is only 6.2 pJ, and the pulse amplitude is more than 240 mV, yielding the highest energy efficiency reported to date in CMOS.i Next, a 3-10 GHz pulsed ring oscillator that offers direct quadrature phase modulation is demonstrated.Current impulses are injected into the oscillator to enable fast startup and implement quadrature phase modulation.The energy consumption and voltage swing varies from 13 pJ and 300 mV at 3 GHz to 18 pJ and 200 mV at 10 GHz respectively, yielding a high energy efficiency.Lastly, a fast switching noise cancelling LNA is proposed for 3.1-10.6GHz UWB applications that settles within 1.3 ns for switching speeds as high as 200 MHz.Inductive peaking is introduced in the noise cancelling topology to achieve a sub-4dB flat noise figure and a high gain of 16.6 dB for frequencies up to 10 GHz.The average power consumption is also below 10 mW with a 50% duty cycle clock.There are several people without whom this thesis would not have been possible.I would like to express my deepest gratitude to my supervisor, Dr. Carlos Saavedra, for his continuous support and guidance throughout both my Masters and my Ph.D.degrees.He has continually
Isolation and Characterization of Novel Marine-Derived Actinomycete Taxa Rich in Bioactive Metabolites (2004)

A unique selective enrichment procedure has resulted in the isolation and identification of two new genera of marine-derived actinobacteria. Approximately 90% of the microorganisms cultured by using the presented method were from the prospective new genera, a result indicative of its high selectivity. In this study, 102 actinomycetes were isolated from subtidal marine sediments collected from the Bismarck Sea and the Solomon Sea off the coast of Papua New Guinea. A combination of physiological parameters, chemotaxonomic characteristics, distinguishing 16S rRNA gene sequences, and phylogenetic analysis based on 16S rRNA genes provided strong evidence for the two new genera (represented by strains of the PNG1 clade and strain UMM518) within the family Micromonosporaceae. Biological activity testing of fermentation products from the new marine-derived actinomycetes revealed that several had activities against multidrug-resistant gram-positive pathogens, malignant cells, and vaccinia virus replication.
Detection of Phosphorylation-Dependent Interactions by Far-Western Gel Overlay (2003)

The far Western gel overlay assay is a highly sensitive tool for the detection of direct protein-protein interactions. The ability to distinguish direct associations between two proteins makes this technique ideal not only for identifying potential binding partners of a protein, but also for characterizing interaction domains and binding sites. The assay relies on the ability of the protein of interest to interact with target proteins that have been immobilized on nitrocelulose filters. Potential interactions can be monitored under various types of conditions by manipulation of the protein that is used as the probe. Such manipulations may include mutagenesis, or protein modifications such as phosphorylation. Detection of phosphorylation-dependent interactions is particularly relevant in light of the fact that many signaling proteins are modified by phosphorylation, which in turn affects activity, localization, and most importantly, the ability to form protein complexes (see refs. , , , ). We describe here the standard protocol for the far-Western gel overlay assay, with modifications that enable the detection of phosphorylation-dependent protein interactions. This technique has been used successfully by our laboratory, as well as others to identify potential phosphorylation-dependent interactions between a number of signaling proteins (, , ).
Structural Analysis of a Chimeric Bacterial α-Amylase. High-Resolution Analysis of Native and Ligand Complexes<sup>,</sup> (2000)

Several chimeric alpha-amylases genes were constructed by an in vivo recombination technique from the Bacillus amyloliquefaciens and Bacillus licheniformis genes. One of the fusion amylases (hereafter BA2), consisting of residues 1-300 from B. amyloliquefaciens and 301-483 from B. licheniformis, has been extensively studied by X-ray crystallography at resolutions between 2.2 and 1.7 A. The 3-dimensional structure of the native enzyme was solved by multiple isomorphous replacement, and refined at a resolution of 1.7 A. It consists of 483 amino acids, organized similarly to the known B. lichiniformis alpha-amylase structure [Machius et al. (1995) J. Mol. Biol. 246, 545-559], but features 4 bound calcium ions. Two of these form part of a linear cluster of three ions, the central ion being attributed to sodium. This cluster lies at the junction of the A and B domains with one calcium of the cluster structurally equivalent to the major Ca(2+) binding site of fungal alpha-amylases. The third calcium ion is found at the interface of the A and C domains. BA2 contains a fourth calcium site, not observed in the B. licheniformis alpha-amylase structure. It is found on the C domain where it bridges the two beta-sheets. Three acid residues (Glu261, Asp328, and Asp231) form an active site similar to that seen in other amylases. In the presence of TRIS buffer, a single molecule of TRIS occupies the -1 subsite of the enzyme where it is coordinated by the three active-center carboxylates. Kinetic data reveal that BA2 displays properties intermediate to those of its parents. Data for crystals soaked in maltooligosaccharides reveal the presence of a maltotriose binding site on the N-terminal face of the (beta/alpha)(8) barrel of the molecule, not previously described for any alpha-amylase structure, the biological function of which is unclear. Data for a complex soaked with the tetrasaccharide inhibitor acarbose, at 1.9 A, reveal a decasaccharide moiety, spanning the -7 to +3 subsites of the enzyme. The unambiguous presence of three unsaturated rings in the (2)H(3) half-chair/(2)E envelope conformation, adjacent to three 6-deoxypyranose units, clearly demonstrates synthesis of this acarbose-derived decasaccharide by a two-step transglycosylation mechanism.
Local Features and Kernels for Classification of Texture and Object Categories: An In-Depth Study (2005)

Recently, methods based on local image features have shown promise for texture and object recognition tasks. This paper presents a large-scale evaluation of an approach that represents images as distributions (signatures or histograms) of features extracted from a sparse set of keypoint locations and learns a Support Vector Machine classifier with kernels based on two effective measures for comparing distributions, the Earth Mover's Distance and the chi-square distance. We first evaluate the performance of our approach with different keypoint detectors and descriptors, as well as different kernels and classifiers. We then conduct a comparative evaluation with several state-of-the-art recognition methods on four texture and five object databases. On most of these databases, our implementation exceeds the best reported results and achieves comparable performance on the rest. Finally, we investigate the influence of background correlations on recognition performance via extensive tests on the PASCAL database, for which ground-truth object localization information is available. Our experiments demonstrate that image representations based on distributions of local features are surprisingly effective for classification of texture and object images under challenging real-world conditions, including significant intra-class variations and substantial background clutter.
RelB and RelE of Escherichia coli Form a Tight Complex That Represses Transcription via the Ribbon–Helix–Helix Motif in RelB (2009)

RelB, the ribbon-helix-helix (RHH) repressor encoded by the relBE toxin-antitoxin locus of Escherichia coli, interacts with RelE and thereby counteracts the mRNA cleavage activity of RelE. In addition, RelB dimers repress the strong relBE promoter and this repression by RelB is enhanced by RelE; that is, RelE functions as a transcriptional co-repressor. RelB is a Lon protease substrate, and Lon is required both for activation of relBE transcription and for activation of the mRNA cleavage activity of RelE. Here we characterize the molecular interactions important for transcriptional control of the relBE model operon. Using an in vivo screen for relB mutants, we identified multiple nucleotide changes that map to important amino acid positions within the DNA-binding domain formed by the N-terminal RHH motif of RelB. Analysis of DNA binding of a subset of these mutant RHH proteins by gel-shift assays, transcriptional fusion assays and a structure model of RelB-DNA revealed amino acid residues making crucial DNA-backbone contacts within the operator (relO) DNA. Mutational and footprinting analyses of relO showed that RelB dimers bind on the same face of the DNA helix and that the RHH motif recognizes four 6-bp repeats within the bipartite binding site. The spacing between each half-site was found to be essential for cooperative interactions between adjacently bound RelB dimers stabilized by the co-repressor RelE. Kinetic and stoichiometric measurements of the interaction between RelB and RelE confirmed that the proteins form a high-affinity complex with a 2:1 stoichiometry. Lon degraded RelB in vitro and degradation was inhibited by RelE, consistent with the proposal that RelE protects RelB from proteolysis by Lon in vivo.
A novel STAT inhibitor, OPB-31121, has a significant antitumor effect on leukemia with STAT-addictive oncokinases (2013)

Signal transduction and activator of transcription (STAT) proteins are extracellular ligand-responsive transcription factors that mediate cell proliferation, apoptosis, differentiation, development and the immune response. Aberrant signals of STAT induce uncontrolled cell proliferation and apoptosis resistance and are strongly involved in cancer. STAT has been identified as a promising target for antitumor drugs, but to date most trials have not been successful. Here, we demonstrated that a novel STAT inhibitor, OPB-31121, strongly inhibited STAT3 and STAT5 phosphorylation without upstream kinase inhibition, and induced significant growth inhibition in various hematopoietic malignant cells. Investigation of various cell lines suggested that OPB-31121 is particularly effective against multiple myeloma, Burkitt lymphoma and leukemia harboring BCR-ABL, FLT3/ITD and JAK2 V617F, oncokinases with their oncogenicities dependent on STAT3/5. Using an immunodeficient mouse transplantation system, we showed the significant antitumor effect of OPB-31121 against primary human leukemia cells harboring these aberrant kinases and its safety for normal human cord blood cells. Finally, we demonstrated a model to overcome drug resistance to upstream kinase inhibitors with a STAT inhibitor. These results suggested that OPB-31121 is a promising antitumor drug. Phase I trials have been performed in Korea and Hong Kong, and a phase I/II trial is underway in Japan.
Energy-efficient analog-to-digital conversion for ultra-wideband radio (2007)

In energy constrained signal processing and communication systems, a focus on the analog or digital circuits in isolation cannot achieve the minimum power consumption. Furthermore, in advanced technologies with significant variation, yield is traditionally achieved only through conservative design and a sacrifice of energy efficiency. In this thesis, these limitations are addressed with both a comprehensive mixed-signal design methodology and new circuits and architectures, as presented in the context of an analog-to-digital converter (ADC) for ultra-wideband (UWB) radio. UWB is an emerging technology capable of high-data-rate wireless communication and precise locationing, and it requires high-speed (&gt;500MS/s), low-resolution ADCs. The successive approximation register (SAR) topology exhibits significantly reduced complex-ity compared to the traditional flash architecture. Three time-interleaved SAR ADCs have been implemented. At the mixed-signal optimum energy point, parallelism and reduced volt-age supplies provide more than 3x energy savings. Custom control logic, a new capacitive DAC, and a hierarchical sampling network enable the high-speed operation. Finally, only a
Pre‐implementation Strategy for CIM (1991)

The probability of a successful CIM implementation is enhanced when the firm takes certain measures to provide the proper environment prior to implementation. A pre‐implementation strategy that stresses the importance of continuous improvement in processes is described. The pre‐implementation strategy is based on a systems analysis and design project procedure that extricates sources of inefficiencies and establishes a foundation of sound management practices.
Effects of a Home-Based Intervention Among Patients With Congestive Heart Failure Discharged From Acute Hospital Care (1998)

Among a cohort of high-risk patients with congestive heart failure, HBI was associated with reduced frequency of unplanned readmissions plus out-of-hospital deaths within 6 months of discharge from the hospital.
Ablation of Ventricular Tachycardia Using Multiple Sequential Transcatheter Application of Radiofrequency Energy (1992)

Multiple sequential radiofrequency energy was applied in the left and right ventricles of 24 dogs to produce large ablated areas limited to endocardial and subendocardial regions. Endocardial ablation was performed in nine dogs with normal ventricles and 15 that had survived remote myocardial infarcts, three with inducible sustained monomorphic ventricular tachycardia. A quadripolar catheter was positioned either at the site of earliest ventricular activation during induced monomorphic ventricular tachycardia or at circumscribed areas of the left ventricle. Radiofrequency energy was delivered between two adjacent poles of the catheter, successively applying radiofrequency energy to the distal, middle, and proximal electrode pairs; this was repeated 9 to 11 times with the catheter in a slightly different position. A cumulative energy of 9,688 +/- 4,191 joules resulted in an ablated endocardial/subendocardial surface area of 4.7 +/- 2.2 cm2 (range 2.4-10 cm2, maximum depth 4 mm). Sustained tachycardia was not inducible by aggressive programmed ventricular stimulation in the dogs with previously inducible tachycardia, indicating successful ablation of the tachycardia foci. Only seven normal dogs were available for electrophysiological studies; three were used in acute and four in chronic studies. Ventricular tachycardia was not induced in the remaining dogs either before or after radiofrequency ablation, indicating the lack of an arrhythmogenic effect of this method. Histologic examination was performed in all nine normal dogs (five were sacrificed for acute pathological examination) as well as in the 15 with myocardial infarction. The late pathological examination of the radiofrequency lesion in these 19 animals showed homogeneous areas of coagulation necrosis and endocardial proliferation. Thus, this modified technique of radiofrequency ablation produced large homogeneous endocardial/subendocardial scars suitable for treating ventricular tachycardia and showed no evidence of an arrhythmogenic influence.
Structural Adaptations to Mechanical Usage. A Proposed “Three-Way Rule” for Bone Modeling (1988)

A collection of fundamental structural adaptations is defined for how compacta and spongiosa respond to overloading in compression, tension and flexure, alone and in combinations. Those adaptations underlie most physiological tissue- and organ-level structural adaptations of healthy intact bones to mechanical usage, so explaining them is a major task for models of mechanical determinants of bone architecture. A biomechanical function called the Gamma function is then devised to predict from a structure's net end-loads and the strain history of any given small bone surface domain, whether mechanically induced formation, resorption or neither will occur in that domain. A separate function is devised to predict local rates of modeling from local strain histories. These functions correctly predict varied details of all of the fundamental adaptations and they also suggest new laws for the mechanical control of bone architecture, some of which are presented. The threeway rule is a new way to analyse the mechanical determinants of bone architecture that accounts for bone-biological realities learned after 1960.
The Use of Unsaturated Hydrocarbons as Boundary Lubricants for Stainless Steels (1967)

Friction and wear experiments with 1-cetene and cetane on stainless steel demonstrated the effect of a carbon-carbon double bond in the boundary lubrication of stainless steel. Experiments with cold-rolled steel, nickel, and chromium indicated the chromium to be the constituent in the steel that is markedly affected. The use of the unsaturated 1-cetene resulted in a lowering of the friction coefficient and the wear over its saturated analog, cetane. It is postulated that the improvement in friction and wear observed using the olefin 1-cetene is due to chemical attachment to the chromium or chromium oxide present in the wearing surface of the stainless steel reducing the amount of intermetallic contact. Experiments using the pure polar olefin vinyl stearate as the lubricant resulted in even further improvement of the frictional properties of stainless steel rubbing surfaces than the olefin alone, and a mechanism is proposed. It is also shown that these same improvements in frictional properties can be obtained when polar olefins such as vinyl stearate are used as additives to ordinary hydrocarbon oils.
A convenient method for the synthesis of macrocyclic tetra-amides by double condensation reaction (1984)

A facile condensation reaction between bifunctional amines and carboxylic acid derivatives has been found to be very efficient for the formation of macrocyclic tetra-amide rings, and tetralactams with 33- to 37-membered rings were readily synthesized in good yields (60–90%).
Evidence for a requirement for ATP hydrolysis at two distinct steps during a single turnover of the catalytic cycle of human P-glycoprotein (2000)

P-glycoprotein (Pgp) is an ATP-dependent hydrophobic natural product anticancer drug efflux pump whose overexpression confers multidrug resistance to tumor cells. The work reported here deals with the elucidation of the energy requirement for substrate interaction with Pgp during the catalytic cycle. We show that the K(d) (412 nM) of the substrate analogue [(125)I]iodoarylazidoprazoin for Pgp is not altered by the presence of the nonhydrolyzable nucleotide 5'-adenylylimididiphosphate and vanadate (K(d) = 403 nM). Though binding of nucleotide per se does not affect interactions with the substrate, ATP hydrolysis results in a dramatic conformational change where the affinity of [(125)I]iodoarylazidoprazoin for Pgp trapped in transition-state conformation (Pgp x ADP x vanadate) is reduced >30-fold. To transform Pgp from this intermediate state of low affinity for substrate to the next catalytic cycle, i.e., a conformation that binds substrate with high affinity, requires conditions that permit ATP hydrolysis. Additionally, there is an inverse correlation (R(2) = 0.96) between 8AzidoADP (or ADP) release and the recovery of substrate binding. These results suggest that the release of nucleotide is necessary for reactivation but not sufficient. The hydrolysis of additional molecule(s) of ATP (or 8AzidoATP) is obligatory for the catalytic cycle to advance to completion. These data are consistent with the observed stoichiometry of two ATP molecules hydrolyzed for the transport of every substrate molecule. Our data demonstrate two distinct roles for ATP hydrolysis in a single turnover of the catalytic cycle of Pgp, one in the transport of substrate and the other in effecting conformational changes to reset the pump for the next catalytic cycle.
Nanocomposite CoPt:C films for extremely high-density recording (1999)

Nanocomposite CoPt:C films were investigated as potential media for extremely high-density recording. An annealing temperature of over 600 °C is necessary to form nanocomposite CoPt:C films consisting of C matrix and fct CoPt nanocrystallites with grain sizes of 8–20 nm and coercivities of 3–12 kOe. Coercivity and grain size increase with increasing annealing temperature and decreasing C concentration and they are insensitive to film thickness. The average activation volumes are about 0.9×10−18 cm3. The properties of these nanocomposite CoPt:C films can be tailored to satisfy the thermal stability, coercivity, and media noise requirements for extremely high-density recording.
Estimation of Total Aromatic Content of Vacuum Gas Oil (VGO) Fractions (370−560 °C) by <sup>1</sup>H NMR Spectroscopy (2005)

In this paper, a quick and direct method has been developed for the quantitative estimation of total aromatics and saturates in a vacuum gas oil (VGO) fractions boiling range (370−560 °C), using 1H NMR spectroscopic techniques. The method is based on the estimation of the average alkyl chain length of substituents on aromatics and the relative group molecular weight of aromatics and saturates. The total aromatics are estimated from the derived equation, which takes into account the relative distribution of CHn (n = 0, 1, 2, 3) groups of aromatics substituents and saturates. The exact assignment of aromatics substituents of α-CHn (n = 1, 2, 3) has been performed by the application of 1H/13C multipulse NMR techniques, such as DEPT-135 and 2D HSQC (edited) (heteronuclear single quantum coherence). The results obtained for several VGO samples from different sources have been in close agreement with those from the open chromatography method (ASTM D-2549-91) and the thin-layer chromatography−flame ionization detection (TLC−FID) method (IP-469).