gebhart/patrepeval huggingface dataset:
Frequency Diverse Array Receiver Architectures (2011)

Typical radar systems are limited to energy distribution characteristics that are range independent. However, operators are generally interested in obtaining information at particular ranges and discarding elsewhere. It seems appropriate then to attempt to put energy solely at the range(s) of interest, thus minimizing exposure to clutter, jammers and other range-dependent interferences sources. The frequency diverse array (FDA) can provide a mechanism to achieve range-dependent beamforming and the spatial energy distribution properties are investigated on transmit and receive for different architectures herein. While simplified FDA receive architectures have been explored, they exclude the return signals from transmitters that are not frequency matched. This practice neglects practical consideration in receiver implementation and has motivated research to formulate a design that includes all frequencies. We present several receiver architectures for a uniform linear FDA, and compare the processing chain and spatial patterns in order to formulate an argument for the most efficient design to maximize gain on target. It may also be desirable to beamsteer in higher dimensionalities than a linear array affords, thus, the transmit and receive concept is extended to a generic planar array. This new architecture allows 3-D beamsteering in angle and range while maintaining practicality. The spatial patterns that arise are extremely unique and afford the radar designer an additional degree of freedom to develop operational strategy. The ability to simultaneously acquire, track, image and protect assets is a requirement of future fielded systems. The FDA architecture intrinsically covers multiple diversity domains and, therefore, naturally lends it self to a multi-mission, multi-mode adar scheme. A multiple beam technique that uses coding is suggested to advance this notion.
Maximum likelihood ratio detection and maximum likelihood DOA estimation based on the vector hydrophone (2003)

A vector hydrophone consists of pressure hydrophone and particle velocity hydrophone, which can co-locately in space and simultaneously in time measures pressure and particle velocity, and obtains acoustic energy flux at a point. In the paper it is shown that in isotropical noise field acoustic energy flux is maximum likelihood ratio detector, its direction is maximum likelihood estimation of source direction. The gain of acoustic energy flux detector and Cramer-Rao Bound (CRB) of Direction of Arrival (DOA) estimation are discussed, and the results of computer simulations and the shallow sea trial are given.
Visualization of intracellular trafficking: use of biotinylated ligands in conjunction with avidin-gold colloids. (1984)

A simple, sensitive method to visualize the binding and internalization of protein ligands by cells in culture is described. A biotinylated toxin was used as ligand, and succinoylated avidin adsorbed onto 5.2 nm gold sols was the electron-dense marker. This method affords direct localization of proteins that are on the cell surface or intracellular without need for techniques that alter membrane integrity.
Synthesis and Structures of Novel Phenyl-Bridged Bis(1-azaallyl) Alkali-Metal Compounds (2000)

The series of dilithium bis(1-azaallyl) compounds [{o-{N(SiMe3)C(R)C(H)}2C6H4}{Li2(TMEDA)2}] (R = But (1), Ph (3)), [{m-{N(SiMe3)C(But)C(H)}2C6H4}{Li2(TMEDA)2}] (5), and [{p-{N(SiMe3)C(But)C(H)}2C6H4}{Li2(TMEDA)2}] (6) have been prepared by addition of the Li−C bond of [{o-/m-/p-(CHSiMe3)2C6H4}{Li2(TMEDA)2}] to a nitrile RCN (R = But, Ph) followed by a 1,3-shift of the SiMe3 group. Likewise, the addition of [{o-(CHSiMe3)2C6H4}{Li2(TMEDA)2}] to an isonitrile ButNC followed by 1,2-trimethylsilyl migration yielded [{o-{N(But)C(SiMe3)C(H)}2C6H4}{Li2(TMEDA)2}] (4). The dilithium compounds 1 and 6 can be further transferred to their potassium analogues [{o-{N(SiMe3)C(But)C(H)}2-C6H4}{K2(TMEDA)}]n (2) and [{p-{N(SiMe3)C(But)C(H)}2C6H4}{K2(THF)3}]2 (7) by reaction with ButOK. The structures of compounds 2−5 and 7 have been determined by X-ray structural analyses.
Preparation, antimicrobial activity, and toxicity of 2‐amino‐4‐arylthiazole derivatives (2006)

Abstract Seven 2‐amino‐4‐aryl‐1,3‐thiazoles ( 1a–g ) and their corresponding 2‐aminoacetyl ( 2a–g ) and 2‐aminoacetyl‐5‐bromo ( 3a–g ) derivatives were synthesized and tested in vitro against 11 reference strains, three Gram‐positive and four Gram‐negative bacteria, two yeasts, and two moulds. Toxicity of the compounds was also evaluated using the brine shrimp test. Compounds 1a, 1b, 1e–g , and 3b showed moderate antimicrobial activity at different concentrations. The results indicated that acetylation of the amino group and bromination at position 5 of the thiazole moiety cause lost of activity. Compounds 1a, 1e , and 1f showed toxicity to brine shrimp nauplii below 10 ppm. Most other compounds showed moderate toxicity, LD 50 above 100 ppm. Structures of all compounds were confirmed by NMR and MS data. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:254–260, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20182
Double lock-in detection for recovering weak coherent radio frequency signals (1985)

A single radio frequency lock-in amplifier reduces broadband noise, but not rf pickup of the same frequency as the signal. If this pickup noise is at least 14 dB stronger than broadband noise, after both have passed through the lock-in, then the signal-to-noise ratio can be improved by applying the lock-in output to a second, low-frequency lock-in which is synchronized to an independent modulation of the signal. Weak coherent radio frequency signals buried in both rf pickup and broadband noise can be recovered by using this double lock-in method, as demonstrated in a plasma diagnostics experiment.
Excavation of pits containing decorated Neolithic pottery and early lithic material of possible Mesolithic date at Spurryhillock, Stonehaven, Aberdeenshire (1998)

This report describes a number of pits and a linear feature close to the scheduled cropmark site at Farrochie. The remains of a shallow curvilinear ditch and eight pits were recovered in one area which produced evidence for possible Mesolithic and Neolithic activity. In another trench a number of truncated pits with no associated artefacts were recorded. There are notes on: `The chipped stone' by B Finlayson (20); `Palaeoenvironmental results' by C Clarke (20--1); and `The Neolithic pottery sherds' by T G Cowie (22--4).
Soft-decision decoding of Reed-Muller codes: recursive lists (2006)

Recursive list decoding is considered for Reed-Muller (RM) codes. The algorithm repeatedly relegates itself to the shorter RM codes by recalculating the posterior probabilities of their symbols. Intermediate decodings are only performed when these recalculations reach the trivial RM codes. In turn, the updated lists of most plausible codewords are used in subsequent decodings. The algorithm is further improved by using permutation techniques on code positions and by eliminating the most error-prone information bits. Simulation results show that for all RM codes of length 256 and many subcodes of length 512, these algorithms approach maximum-likelihood (ML) performance within a margin of 0.1 dB. As a result, we present tight experimental bounds on ML performance for these codes
Comprehensive sequence and structure analysis of algal lipid catabolic enzyme Triacylglycerol lipase: an <i>in silico</i> study to vitalize the development of optimum engineered strains with high lipid productivity (2021)

Microalgae as an alternative renewable resource for biofuel production have captured much significance. Nonetheless, its economic viability is a field of major concern for researchers. Unraveling the lipid catabolic pathway and gaining insights into the sequence-structural features of its primary functioning enzyme, Triacylglycerol lipase, will impart valuable information to target microalgae for augmented lipid content. In the present study, a genome-wide comparative study on putative Triacylglycerol lipase (TAGL) enzyme from algal species belonging to varied phylogenetic lineages was performed. The comprehensive sequence analysis revealed that TAGL comprises of three distinct conserved domains, such as, Patatin, Class III Lipase, and Abhydro_lipase, and also confirmed the ubiquitous presence of GXSXG motif in the sequences analyzed. In the absence of a crystal structure of algal TAGL till date, we developed the first 3D model of patatin domain of TAGL from an oleaginous microalga, <i>Phaedactylum tricornutum</i>, employing homology modeling, docking and molecular dynamic simulations methods. The domain-substrate complex having the low-ranking docking score revealed the binding of palmitic acid to the TAGL patatin domain surface with strong hydrogen bond interactions. The simulation results implied that the substrate-complexed patatin domain and the free enzyme adopted a more stable conformation after 40 ns. This is the first ever attempt to provide <i>in-silico</i> insights into the structural and dynamical insights on catalytic mechanism of the TAGL patatin domain. Subsequently, these findings aided our understanding on their structural stability, folding mechanism and protein-substrate interactions, which could be further utilized to design site-specific mutagenic experiments for engineering microalgal strains.Communicated by Ramaswamy H. Sarma.
Distinct Roles of the Active-site Mg2+ Ligands, Asp882 and Asp705, of DNA Polymerase I (Klenow Fragment) during the Prechemistry Conformational Transitions (2010)

DNA polymerases catalyze the incorporation of deoxynucleoside triphosphates into a growing DNA chain using a pair of Mg(2+) ions, coordinated at the active site by two invariant aspartates, whose removal by mutation typically reduces the polymerase activity to barely detectable levels. Using two stopped-flow fluorescence assays that we developed previously, we have investigated the role of the carboxylate ligands, Asp(705) and Asp(882), of DNA polymerase I (Klenow fragment) in the early prechemistry steps that prepare the active site for catalysis. We find that neither carboxylate is required for an early conformational transition, reported by a 2-aminopurine probe, that takes place in the open ternary complex after binding of the complementary dNTP. However, the subsequent fingers-closing step requires Asp(882); this step converts the open ternary complex into the closed conformation, creating the active-site geometry required for catalysis. Crystal structures indicate that the Asp(882) position changes very little during fingers-closing; this side chain may therefore serve as an anchor point to receive the dNTP-associated metal ion as the nucleotide is delivered into the active site. The Asp(705) carboxylate is not required until after the fingers-closing step, and we suggest that its role is to facilitate the entry of the second Mg(2+) into the active site. The two early prechemistry steps that we have studied take place normally at very low Mg(2+) concentrations, although higher concentrations are needed for covalent nucleotide addition, consistent with the second metal ion entering the ternary complex after fingers-closing.
Studies on Pyrimidine Derivatives. VII (1960)

The product of the condensation of 5-amino-1, 2, 4-triazole (I) and diethyl ethoxy-methylenemalonate (II) was proved to be 6-ethoxycarbonyl-7-hydroxy-1, 2, 4-triazolo-[2, 3-α]pyrimidine (XI). Reaction of ethyl 2-cyano-3-ethoxyacrylate afforded 6-ethoxycarbonyl-7-amino-1, 2, 4-triazolo[2, 3-α]pyrimidine (XTV), 6-cyano-7-hydroxy-1, 2, 4-triazolo [2, 3-α]pyrimidine (XV), and ethyl 2-cyano-3-(1, 2, 4-triazol-5-ylamino) acrylate (XXI). 5-Hydroxy-6-ethoxycarbonyl-1, 2, 4-triazolo[4, 3-α]pyrimidine (X) and 5-hydroxy-6-cyano-1, 2, 4-triazolo [4, 3-α] pyrimidine (XX) were prepared and these were found to undergo isomerization on being heated to fusion, forming (XI) from (X) and (XV) from (XX).
The nutritional causes of colorectal cancer: An introduction to the melbourne study (1987)

The Melbourne study has shown that dietary factors and alcohol are important in the cause and prevention of colorectal cancer (CRC). A high intake of fat and beef probably causes CRC, and a high intake of beer possibly causes rectal cancer. The beef and beer effects were both independent of other dietary variables, but further research is indicated to explore the mechanisms of their actions. Foods of plant origin protected against CRC, and the "plant food hypothesis" now replaces the dietary fiber hypothesis. Further study is needed on the interrelationships between various foods of plant origin. Vitamin supplements were protective, and again clarification is needed on the mechanism of action. In high-risk populations, nutritional risk and causal factors are likely to be difficult to find, whereas protective factors are likely to be found with greater ease. Further analysis of the Melbourne data will reveal the importance of diet in CRC causation, relative to the other hypothesized causal and protective factors.
The changing landscape of English: implications for language assessment (2005)

This article offers a response to the comments and claims made in Jennifer Jenkins' article, ‘The spread of English as an International Language: a testing time for testers’. It examines some assumptions underpinning her views and responds to claims about current policy and practice in English language testing. It goes on to explain the key factors which frame the way in which examination boards deal with varieties of English in their tests and discusses the contribution that the language testing community can make to increase our understanding of language variation.
New FDA migration cell used to study migration of styrene from polystyrene into various solvents. (1985)

A new cell was evaluated for studying the migration of components of plastic food packaging materials into various food simulating solvents. Data obtained using this cell to study the migration of styrene from polystyrene at 40 and 70 degrees C are presented. Food simulating solvents tested were: water; 3% acetic acid; 8, 20, 50, and 100% ethanol; corn oil; HB-307; heptane; hexadecane; and decanol. An iterative Basic computer program is described that fits the migration vs time data obtained to mathematical models, based on Ficks' law, yielding migrant/polymer diffusion coefficients (Dp). Dp values determined for styrene migration from polystyrene at 40 and 70 degrees C were 3 X 10(-13) and 4 X 10(-12) sq. cm/s, respectively.
Effect of Colicin E3 upon the 30S Ribosomal Subunit of <i>Escherichia coli</i> (1971)

The properties of 30S ribosomal subunits from untreated and from colicin E3-treated (E3-30S) bacteria have been compared. Polyacrylamide gel electrophoresis of ribosomal proteins revealed no difference, but several studies indicated that the 16S RNA from E3-30S particles was modified. E3-16S RNA showed slightly increased resistance to heat-induced degradation and had a reduced (15 S) sedimentation coefficient on sucrose gradients. Fingerprint analyses of E3-16S RNA revealed that the 3'-terminus of the molecule had been deleted. It was concluded that a primary effect of colicin E3 is the activation of a highly specific RNase that degrades 30S ribosomal RNA in situ, and that the resulting fragment(s) are probably retained within the 30S particle.
Physikalische und metallkundliche Vorgänge beim Nitrieren im Plasma einer Glimmentladung (1974)

Article Physikalische und metallkundliche Vorgänge beim Nitrieren im Plasma einer Glimmentladung was published on March 1, 1974 in the journal HTM Journal of Heat Treatment and Materials (volume 29, issue 2).
Human NT2/D1 cells differentiate into functional astrocytes (1999)

As the most numerous cell type in the brain, astrocytes are coupled via gap junction channels. It is believed that communication among astrocytes is normally regulated by extracellular ions, neurotransmitters and neuromodulators. However, the level of astrocytic coupling is altered in abnormal conditions such as stroke, brain trauma and Alzheimer's disease. A well established human progenitor cell line, NT2/D1, has been previously differentiated into pure neuronal cultures. In the current study, for the first time, we report the differentiation of NT2/D1 cells into astrocytes, which express connexin43 and are coupled via gap junctions. Thus, human NT2/D1 cells are not merely committed neuronal progenitors but, similar to the embryonal stem cells, they can give rise to both lineages.
Dark currents in double-heterostructure and quantum-well solar cells (2002)

Numerical modelling shows that the separation of the quasi-Fermi potentials in the lower bandgap region of a double-heterostructure may be less than the terminal voltage, resulting in smaller dark currents than would be expected if flat quasi-Fermi levels were assumed. Quasi-Fermi level variations occur as a response to carrier transport limitation by drift and diffusion within the space-charge region or by thermionic emission. This is a possible explanation for the low dark currents which have been measured in quantum-well p-i-n solar cells. This effect, together with evidence that photogenerated carriers can escape from quantum wells with high efficiency, suggests that the inclusion of low-bandgap regions in the depletion regions of solar cells may lead to high efficiency devices.
Subsea Processing System Ready for Gulf of Mexico Field (1993)

ABSTRACT: Use of subsea processing (i.e. subsea separation and Single phase pumping) to produce smaller more remote oil fields has been the subject of field tests and studies since 1969, reported in 9 OTC papers from 1974-1992. The advance in GLASS [a] is to create a relatively "low tech" and proven solution. Although originally intended for the Gulf of Mexico, it may be applicable in Brasilian, North Sea and other areas. Parallel with the engineering development, composite judgments have been developed for the economic performance for CAPEX and OPEX using recently available probabilistic methods. Connector advances in 1991–1992 may further simplify use of this system design. Application is relatively insensitive to water depths, e.g. 300–3,000fi. Offset distances from a host platform may be in the region of 5–50 miles. The system was developed for a Base Case in l,500ft. of water with 12,000 bopd initial production with 8 wells from a 25 MMBBL recoverable reservoir, with GORS in the region of 1,000 scf/bbl. Installation equipment comprises the semisubmersible drilling unit and standard offshore service vessels, implying economy and flexibility for use in worldwide application. Hydrate, sand, shutdown and startup operating conditions were addressed. PRECEDENT SINCE 1969: The first trials for a subsea processing system were the experiments in 1969-1971 offshore Abu Dhabi at the Zakum field, conducted by BP and Total when they installed a subsea separator and booster pump in about 72 feet of water and operated the system over a three year period, including a year long period when about 1.7 MMBBL of oil was produced. OTC paper no. 1942 in 1974 outlined this pioneering effort. That prior work was systemized and updated for North Sea field conditions in the GA-SP project (e.g. 30,000 bopd from 4 wells in 984 fl. of water), culminating in full scale prototype trials in a dry doc kin 1990on behalf of eight operators: it was reported in OTC papers 6722, 6766 and 6767 in 1991. This system design used water injection hydraulic power to drive the booster pump, a 4 level component arrangement and a multiple stage subsea separator to provide oil of export quality from a hypothetical arrangement of 4 producing wells with 4 water injection wells, with GORS of about 450. Another series of experiments with a subsea separator was made in live offshore conditions in about 248 ft. of water, near the base of a platform in the North Sea operated by Hamilton Brothers. This test series with the BOET separator design is reported in OTC paper nos. 5922 and 6423 in 1989 and 1990, respectively. It would therefore appear that significant precedent now exists for subsea processing - indicating it is concept whose time has arrived. ENHANCED RECOVERY FROM REDUCTION IN WELL BACK PRESSURE: A major benefit of the use of subsea separation and boosting in deep water is that the back pressure on the wells can be reduced and total recovery can be enhanced.
A new diffusion algorithm during oxidation which can handle both phosphorus pile-up and boron segregation at Si-SiO/sub 2/ interface (2002)

A new simulation algorithm during oxidation which can handle both the phosphorus (P) pile-up and the boron (B) segregation has been proposed. In this algorithm, an interlayer (IL) is placed at Si-SiO/sub 2/ interface in order to have P pile-up. The interface is moved according to the Si consumption during a time step and a new interface is generated at the end of the consumed Si region. A region between an old and a new IL is defined as a transition layer (TL). A diffusion equation is solved inside the TL using local effective diffusion constants in order to fully redistribute the impurities. By using this "diffusion in the TL", the P piled up in the old IL may move through the TL and re-piles up into the new IL, and B segregation can be simulated accurately. The V/sub th/-V/sub sub/ characteristics of an actual buried channel pMOSFET which is simulated using the proposed algorithm agrees well with the experiment.
Vagus nerve stimulation: a new promising therapeutic tool in inflammatory bowel disease (2017)

Inflammatory bowel disease (IBD), that is Crohn's disease (CD) and ulcerative colitis, affects about 1.5 million persons in the USA and 2.2 million in Europe. The pathophysiology of IBD involves immunological, genetic and environmental factors. The treatment is medico-surgical but suspensive. Anti-TNFα agents have revolutionized the treatment of IBD but have side effects. In addition, a non-negligible percentage of patients with IBD stop or take episodically their treatment. Consequently, a nondrug therapy targeting TNFα through a physiological pathway, devoid of major side effects and with a good cost-effectiveness ratio, would be of interest. The vagus nerve has dual anti-inflammatory properties through its afferent (i.e. hypothalamic-pituitary-adrenal axis) and efferent (i.e. the anti-TNFα effect of the cholinergic anti-inflammatory pathway) fibres. We have shown that there is an inverse relationship between vagal tone and plasma TNFα level in patients with CD, and have reported, for the first time, that chronic vagus nerve stimulation has anti-inflammatory properties in a rat model of colitis and in a pilot study performed in seven patients with moderate CD. Two of these patients failed to improve after 3 months of vagus nerve stimulation but five were in deep remission (clinical, biological and endoscopic) at 6 months of follow-up and vagal tone was restored. No major side effects were observed. Thus, vagus nerve stimulation provides a new therapeutic option in the treatment of CD.
Intelligent Media Agents (1999)

Intelligent agents are rescuer in the information glut. They help users to find information which better corresponds to their interests and needs. This book describes the architecture and basic modules of an intelligent media agent. A personal television guide is described as an example of intelligent help, addressing the problem of managing TV channels by using an intelligent agent