Energy Technology Data Exchange (ETDEWEB)

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Energy Technology Data Exchange (ETDEWEB)

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International Nuclear Information System (INIS)

The aim of the present study is to identify and characterize the antimalrial agents from traitional Sudanese medicinal plants. 49 plants parts representing 26 species from 15 families were extracted and screened for their in vitro antimalrial activity using P. falciparum strain 3D7 which is chloroquine sensitive and Dd2 strain which is chloroquine resistant and pyrimethamine sensitive.The plant species investigated exhibited diverse botanical families. They includes Annonaceae, Aristolochiaceae, Asteraceae, Balantiaceae, Caesalpiniceae, Celasteraceae, Cucurbitaceae, Fabaceae, Graminae, Meliaceae, Myrtaceae, Polygonaceae, Rubiaceae, Rutaceae, and simaroubaceae. The evaluation of these plants for their antimalarial activity and their effect on lymphocyte proliferation was carried out. 57 extracts were tested on the chloroquine sensitive strain (3D7). Where 34 extracts (59%) exhibited significant activity against 3D7 with IC_5_0 values #100 #mu# g/ml), where as Sonochous cornatus, ...

UK PubMed Central (United Kingdom)

Interactions of myristic acid with bovine serum albumin were studied by 13C NMR spectroscopy at 50.3 MHz using 90% isotopically substituted [1-13C]-, [3-13C]-, and [14-13C]myristic acids, either individually...Full Text Available

British Library Electronic Table of Contents (United Kingdom)

Summary: The surface coverage of amorphous silica gels used in the synthesis of silica polyamine composites has been investigated by 29Si NMR. By diluting the polyamine anchor silane, chloropropyl trichlorosilane, with methyl trichlorosilane it was found that surface coverage could be markedly improved for a range of amine polymers after grafting to the silica surface. The commensurate decrease in the number of anchor points and increase in the number of free amines results in an increase in metal capacity and/or an improvement in capture kinetics. Solid state CPMAS-13C NMR has been employed to investigate the structure and metal ion binding of a series of these composite materials. It is reported that the highly branched polymer, poly(ethyleneimine) (PEI) exhibits much broader 13C NMR res...

Energy Technology Data Exchange (ETDEWEB)

The surface coverage of amorphous silica gels used in the synthesis of silica polyamine composites has been investigated by 29Si NMR. By diluting the polyamine anchor silane, chloropropyl trichlorosilane, with methyl trichlorosilane it was found that surface coverage could be markedly improved for a range of amine polymers after grafting to the silica surface. The commensurate decrease in the number of anchor points and increase in the number of free amines results in an increase in metal capacity and/or an improvement in capture kinetics. Solid state CPMAS-13C NMR has been employed to investigate the structure and metal ion binding of a series of these composite materials. It is reported that the highly branched polymer, poly(ethyleneimine) (PEI) exhibits much broader 13C NMR resonances than the linear polymers poly(allylamine) (PAA) and poly(vinylamine) (PVA). ...

Energy Technology Data Exchange (ETDEWEB)

Aqueous solutions of 2-amino-2-hydroxymethyl-1,3-propanediol (AHPD), a sterically hindered amine, was examined as a potential CO{sub 2} absorbent and compared with the most commonly used absorbent, monoethanolamine (MEA) solution, through equilibrium solubility measurements and {sup 13}C NMR spectroscopic analyses. The solubilities of CO{sub 2} in aqueous 10 mass % AHPD solutions were higher than those in aqueous 10 mass% MEA solutions above 4 kPa at 298.15 K, but lower below 4 kPa. The solubility difference between these two solutions increased with the CO{sub 2} partial pressures above the crossover pressure. Equilibrated CO{sub 2}-MEA-H{sub 2}O and CO{sub 2}-AHPD-H{sub 2} solutions at various CO{sub 2} partial pressures ranging from 0.01 to 3000 kPa were analyzed by {sup 13}C NMR spectroscopy. AHPD contains more hydroxyl groups than nonhindered MEA, and hence ...

British Library Electronic Table of Contents (United Kingdom)

A series of [60]fullerene-substituted phenylalanine (Baa) and lysine derivatives have been prepared by the condensation of 1,2-(4prime-oxocyclohexano)fullerene with the appropriately protected (4-amino)phenylalanine and lysine, respectively. Conversion of the imine to the corresponding amine is achieved by di-acid catalyzed hydroboration. The reduction of the imine is not accompanied by hydroboration of the fullerene cage. The [70]fullerene phenylalanine derivative has also been prepared as have the di-amino acid derivatives. The compounds were characterized by MALDI-TOF mass spectrometry, UV/Vis spectroscopy, and cyclic voltammetry. 1H and 13C NMR spectroscopy allowed the observation of diastereomers. Fullerene-substituted peptides may be synthesized on relatively large scale by solid-pha...

British Library Electronic Table of Contents (United Kingdom)

The endophytic fungus Trichothecium roseum LZ93 from Maytenus hookeri was found to antagonize other pathogenic fungi in vitro. To identify which compound contributed substantially to the antagonism, we fermented the strain and purified its fermentation products. Eleven compounds were obtained, including two trichothecenes, five rosenonolactones, two cardiotonic cyclodepsipeptides, and two sterols. Compound 11?-hydroxyrosenonolactone (1) was assigned according to 1D and 2D-NMR data for the first time. At the same time, the 1H and 13C-NMR assignments for 6?-hydroxyrosenonolactone (2) were revised. Of all of them, only trichothecin (6) showed strong antifungal activity. Based on our observations of the antagonistic activity and the other experimental results, we suggest that the antifungal co...

British Library Electronic Table of Contents (United Kingdom)

The monoanionic bidentate Schiff base, N-(phenolyl)-benzaldimine (HL), has been employed to synthesize a new vanadium(IV) complex of general composition [VO(L)2] (where L = O, N donor of Schiff base). The ligand and complex have been fully characterized by elemental analyses, molar conductance data, FT-IR, 1H- and 13C-NMR, and UV-Vis spectroscopies. Oxidation of alcohols to their corresponding aldehydes and ketones was conducted by this complex catalyst using Oxone as oxidant under biphasic reaction conditions (CH2Cl2/H2O) and tetra-n-butylammonium bromide as phase transfer agent under air at room temperature.

British Library Electronic Table of Contents (United Kingdom)

New palladium(II) complexes (2), bearing NHC/TPPTS ligands, (NHC=benzimidazol-2-ylidene; TPPTS=triphenylphosphine-3,3',3''-trisulfonic acid trisodium salt) have been prepared and characterized by elemental analyses and spectroscopic methods. Their ability to catalyze the Suzuki-Miyaura reaction in neat water has been studied at 100^oC. Very high activities have been observed in the coupling of phenylboronic acid with aryl chlorides in the presence of 1% of the catalyst. We have compared the electronic properties of cis-[PdBr2(NHC)(TPPTS)] with the related complexes, [PdX2(NHC)]2 and [trans-PdBr2(NHC)(pdca)] (pdca=pyridine-2,6-dicarboxyic acid) (3) via three different techniques: cyclic voltammetry, thermogravimetric analysis and ^1^3C NMR spectroscopy.

Science.gov (United States)

New tetradentate N(2)O(2) donor Schiff bases and their mononuclear Co(II), Ni(II), Cu(II), and Pd(II) complexes were synthesized and characterized extensively by IR, (1)H-, (13)C-NMR, mass, ESR, conductivity measurements, elemental and thermal analysis. Specifically the magnetic and electronic spectral measurements demonstrate the octahedral structures of cobalt(II), nickel(II) complexes and square planar geometries of copper(II), palladium(II) complexes. All the ligands and complexes were screened for their in vitro antibacterial activity against two gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus) and two gram-negative bacteria (Escherichia coli, Klebsiella pneumonia). In this study, Pd(II) complexes exhibited potent antibacterial activity against B. subtilis, S. aureus whereas other metal complexes also exerted good activity towards all tested strains even than standard drugs streptomycin and ampicillin. PMID:21297294

British Library Electronic Table of Contents (United Kingdom)

New Schiff base derivatives (L1 and L2) were prepared by the condensation of 2-hydroxy-3-methoxybenzaldehyde (o-vanillin) and 3-hydroxy-4-methoxybenzaldehyde (iso-vanillin) with 5-methylfurfurylamine. Two new complexes [Ni(L1)2] and [Cu(L1)2] have been synthesized with bidentate NO donor Schiff base ligand (L1). The Ni(II) and Cu(II) atoms in each complex are four coordinated in a square planar geometry. Schiff bases (L1 and L2) and complexes [Ni(L1)2] and [Cu(L1)2] were characterized by elemental analyses, FT-IR, UV-vis, mass and 1H, 13C NMR spectroscopies. The crystal structures of the ligand (L2) and complexes [Ni(L1)2] and [Cu(L1)2] have also been determined by using X-ray crystallographic technique.

British Library Electronic Table of Contents (United Kingdom)

The structure of the O-antigen polysaccharide (PS) from Escherichia coli O177 has been determined. Component analysis together with 1H and 13C NMR spectroscopy experiments was used to determine the structure. Inter-residue correlations were determined by 1H,13C-heteronuclear multiple-bond correlation and 1H,1H-NOESY experiments. PS is composed of tetrasaccharide repeating units with the following structure: 2)-a-l-Rhap-(13)-a-l-FucpNAc-(13)-a-l-FucpNAc-(13)-b-d-GlcpNAc-(1 An a-l-Rhap residue is suggested to be present at the terminal part of the polysaccharide, which on average is composed of 20 repeating units, since the 1H and 13C chemical shifts of an a-linked rhamnopyranosyl group could be assigned by a combination of 2D NMR spectra. Consequently, the biological repeating unit has a 3-...

Energy Technology Data Exchange (ETDEWEB)

The influence of membrane pH gradients on the transbilayer distribution of some common phospholipids has been investigated. The authors demonstrate that the transbilayer equilibrium of the acidic phospholipids egg phosphatidylglycerol (EPG) and egg phosphatidic acid (EPA) can be manipulated by membrane proton gradients, whereas phosphatidylethanolamine, a zwitterionic phospholipid, remains equally distributed between the inner and outer monolayers of large unilamellar vesicles (LUVs). Asymmetry of EPG is examined in detail and demonstrated by employing three independent techniques: ion-exchange chromatography, {sup 13}C NMR, and periodic acid oxidation of the (exterior) EPG headgroup. In the absence of a transmembrane pH gradient ({Delta}pH) EPG is equally distributed between the outer and inner monolayers of LuVs. When vesicles composed of either egg phosphatidylcholine (EPC) or DOPC together with 5 mol % EPG are prepared ...

British Library Electronic Table of Contents (United Kingdom)

A tertiary structure of recombinant A22^G-B31^K-B32^R-human insulin monomer (insulin GKR) has been characterized by ^1H, ^1^3C NMR at natural isotopic abundance using NOESY, TOCSY, ^1H/^1^3C-GHSQC, and ^1H/^1^3C-GHSQC-TOCSY spectra. Translational diffusion studies indicate the monomer structure in water/acetonitrile (65/35vol.%). CSI analysis confirms existence of secondary structure motifs present in human insulin standard (HIS). Both techniques allow to establish that in this solvent recombinant insulin GKR exists as a monomer. Starting from structures calculated by the program CYANA, two different refinement protocols used molecular dynamics simulated annealing with the program AMBER; in vacuum (AMBER_VC), and including a generalized Born solvent model (AMBER_GB). From these calculation...

International Nuclear Information System (INIS)

Selected derivatives of cyclophosphamide (CP) metabolites were synthesized and the solution chemistry of each was studied by "3"1P nuclear magnetic resonance (NMR) spectroscopy under a standard set of reaction conditions at physiological pH (7.4) and temperature (37"0C). Complementary "2H and "1"3C NMR spectral data was obtained using isotopically ("2G and "1"3C) enriched CP metabolites. The CP derivatives were synthesized by the ozonolysis of substituted 3-butenyl phosphorodiamidates, and were isolated as analogues of either cis and trans 4-hydroperoxy-CP or aldophosphamide (AP). The relative ratios of the tautomeric species, 4-hydroxy-CP and AP, and their half-lives (T/sub 1/2/) were measured by "3"1P NMR spectroscopy. The influence of CP metabolites on perfused U-937 cells, a CP-sensitive human lymphoma, was observed by high resolution "3"1P NMR spectroscopy. In this manner, it was possible to measure, for the first time, a rate constant for the intracellular disappearance of ...

British Library Electronic Table of Contents (United Kingdom)

A mixture of long-chain hydrocarbons constituted by nonacosane (29C, 7.5%), hentriacontane (31C, 48.3%), and tritriacontane (33C, 30.1%), the ester 1?-acetyloxymethylpentacosa-20?-enyl 10-hydroxydecanoate (2), ?-amyrin (3), friedelin (4), and lupeol (5), and 3?-hydroxy-D:B-friedo-olean-5-ene (6) were identified as constituents of fruits of Maytenus salicifolia Reissek (Celastraceae). The structural formula and the stereochemistry of compound 6 were established by the data obtained through 1H and 13C NMR spectroscopy, including DEPT-135 and 2D (HMQC, HMBC, and NOESY) experiments. By analysis of the spectral data, it was possible to correct seven chemical shift assignments of compound 6, which were erroneous attributed and published in the scientific literature.

UK PubMed Central (United Kingdom)

Pooling and synthesizing signals across different senses often enhances responses to the event from which they are derived. Here we examine whether multisensory response enhancements are attributable...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundThe zinc-finger transcription factor GLI3 is an important mediator of Sonic hedgehog signaling and crucial for patterning of many aspects of the vertebrate body plan. In...Full Text Available

Science.gov (United States)

Silanization of the silica gel surface in the synthesis of silica gel polyamine composites uses (chloropropyl)-trichlorosilane (CPTCS). It is possible to substitute a molar fraction of reagent CPTCS with methyltrichlorosilane (MTCS), creating a mixed silane surface layer. Two types of silica gels were modified with a series of MTCS:CPTCS molar ratios. Solid-state CP/MAS 29Si and 13C NMR spectroscopies were used to evaluate the surface silane composition. Surface silane coverage was markedly improved for the resulting gels. When polyamines were grafted to the resultant MTCS:CPTCS silane layers, it was shown that the decrease in the number of propyl attachments to the polyamine resulted in increased quantities of ''free amines''. Optimum MTCS:CPTCS ratios were determined for three polyamines grafted onto one silica gel. A substantial free amine increase was observed for poly(allylamine) ...

International Nuclear Information System (INIS)

A single round of Edman degradation was employed to remove the NH_2-terminal valine from isolated #alpha# chains of human hemoglobin. Reconstitution of normal #beta# chains with truncated or substituted #alpha# chains was used to form truncated (des-Val"1-#alpha#1) and substituted ([[1-"1"3C]Gly"1]#alpha#1) tetrameric hemoglobin analogs. Structural homology of the analogs with untreated native hemoglobin was established by using several spectroscopic and physical methods. Functional studies indicate that the reconstituted tetrameric protein containing des-Val"1-#alpha# chains has a higher affinity for oxygen, is less influenced by chloride ions or 2,3-biphosphoglycerate, and shows lower cooperativity than native hemoglobin. These results confirm the key functional role of the #alpha#-chain NH_2 terminus in mediating cooperative oxygen binding across the dimer interface. The NH_2-terminal pK/sub 1/2/ value was determined for the ["1"3C]glycine-substituted analog to be 7.46 +/- 0.09 at ...

Energy Technology Data Exchange (ETDEWEB)

Low-temperature catalytic pretreatment is a promising approach to the development of an improved liquefaction process- This work is a fundamental study on effects of pretreatments on coal structure and reactivity in liquefaction. The main objectives of this project are to study the coal structural changes induced by low-temperature catalytic and thermal pretreatments by using spectroscopic techniques; and to clarify the pretreatment-induced changes in reactivity or convertibility of coals in the subsequent liquefaction. This report describes the recent progress of our work. Substantial progress has been made in the spectroscopic characterization of structure and pretreatment-liquefaction reactions of a Montana subbituminous Coal (DECS-9), and thermochemical analysis of three mw and reacted bituminous coals. Temperature programmed liquefaction has been performed on three low-rank coals both in the presence and absence of dispersed molybdenum sulfide catalyst. We also performed a ...

CERN Document Server

We consider the impact of a 4th generation on Higgs to $\\gamma\\gamma$ and $WW,ZZ$ signals and demonstrate that the Tevatron and LHC have essentially eliminated the possibility of a 4th generation if the Higgs is SM-like and has mass below 200 GeV. We also show that the absence of enhanced Higgs signals in current data sets in the $\\gamma\\gamma$ and $WW,ZZ$ final states can strongly constrain (almost eliminate) the possibility of a 4th generation in two-Higgs-doublet models of type II (in the MSSM).

Energy Technology Data Exchange (ETDEWEB)

We investigate the possibility of observing strong interactions of longitudinally polarized weak vector bosons in the process {gamma}{gamma} {yields} ZZ at a photon linear collider. We make use of polarization of the photon beams and cuts on the decay products of the Z bosons to enhance the signal relative to the background of transversely polarized ZZ pairs. We find that the background overwhelms the signal unless there are strong resonant effects, as for instance from a technicolor analogue of the hadronic f{sub 2}(1270) meson.

British Library Electronic Table of Contents (United Kingdom)

Wnt signaling negatively regulates adipocyte differentiation, and ectopic expression of Wnt-1 in 3T3-L1 cells induces several downstream molecules of Wnt signaling, including Wnt-1 inducible signaling pathway protein (WISP)-2. In this study, we examined the role of WISP-2 in the process of adipocyte differentiation using an in vitro cell culture system. In the differentiation of 3T3-L1 cells, WISP-2 expression was observed in growing cells and declined thereafter. In the mitotic clonal expansion phase of adipocyte differentiation, WISP-2 expression was transiently down-regulated concurrently with up-regulation of CCAAT/enhancer-binding protein d expression. Treatment of 3T3-L1 cells in the differentiation medium with lithium, an activator of Wnt signaling, inhibited the differentiation pro...

Energy Technology Data Exchange (ETDEWEB)

An electrochemical detection method for analyzing sequence-specific DNA using gold nanoparticle DNA probes and subsequent signal amplification step by silver enhancement is described. The assay relies on the electrostatic adsorption of target oligonucleotides onto the sensing surface of the glassy carbon electrode (GCE) and its hybridization to the gold nanoparticle-labeled oligonucleotides DNA probe. After silver deposition onto gold nanoparticles, binding events between probe and target were monitored by the differential pulse voltammetry (DPV) signal of the large number of silver atoms anchored on the hybrids at the electrode surface. The signal intensity difference permits to distinguish between the match of two perfectly matched DNA strands and the near-perfect match where just one base pair was wrong. Coupled with this 'nanoparticle-promoted' reduction of silver ...

Energy Technology Data Exchange (ETDEWEB)

A hysteretic subcritical period-doubling bifurcation is observed in the nonlinear strain dynamics of a magnetostrictive oscillator. The dynamic strain response of the magnetostrictive oscillator was observed with a high-resolution fiber optic interferometer. The effects of low-frequency modulation and band-limited stochastic fluctuations on such a bifurcation are investigated. Power spectral density measurements show that for an optimal value of externally injected noise the signal-to-noise ratio of a low-frequency modulation signal is enhanced by greater than 14 dB, thus indicating the first experimental observation of stochastic resonance near a bistable period-doubling bifurcation. 10 refs., 7 figs.

CERN Document Server

The detection of a stochastic background of gravitational waves could significantly impact our understanding of the physical processes that shaped the early Universe. The challenge lies in separating the cosmological signal from other stochastic processes such as instrument noise and astrophysical foregrounds. One approach is to build two or more detectors and cross correlate their output, thereby enhancing the common gravitational wave signal relative to the uncorrelated instrument noise. When only one detector is available, as will likely be the case with the Laser Interferometer Space Antenna (LISA), alternative analysis techniques must be developed. Here we show that models of the noise and signal transfer functions can be used to tease apart the gravitational and instrument noise contributions. We discuss the role of gravitational wave insensitive "null channels" formed from particular combinations ...

British Library Electronic Table of Contents (United Kingdom)

Transgenic plants offer advantages for biomolecule production because plants can be grown on a large scale and the recombinant macromolecules can be easily harvested and extracted. We introduced an Aspergillus phytase gene into canola (Brassica napus) (line 9412 with low erucic acid and low glucosinolates) by Agrobacterium-mediated transformation. Phytase expression in transgenic plant was enhanced with a synthetic phytase gene according to the Brassica codon usage and an endoplasmic reticulum (ER) retention signal KDEL that confers an ER accumulation of the recombinant phytase. Secretion of the phytase to the extracellular fluid was also established by the use of the tobacco PR-S signal peptide. Phytase accumulation in mature seed accounted for 2.6% of the total soluble proteins. The enzy...

UK PubMed Central (United Kingdom)

Programmed cell death (PCD) is triggered when Pto, a Ser-Thr protein kinase, recognizes either the AvrPto or AvrPtoB effector from Pseudomonas syringae pv tomato. This...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Positron emission tomography (PET) and magnetic resonance imaging (MRI) studies were performed on a case of neuro-Behcet's syndrome. In accordance with the clinical signs, FDG PET (using /sup 18/F-labeled 2-F-2'-desoxyglucose) revealed disseminated storage defects in the cerebrum and cerebellum. Focal regions of enhanced signal intensity were demonstrated in the parietal white matter of the cerebrum in T2-weighted images and in the brain stem by MRI. (orig.).

Energy Technology Data Exchange (ETDEWEB)

Objective: To assess dynamic MRI with Gd-DTPA enhancement for evaluating inflammatory changes in the subacromial bursa. Design and patients: We detected the signal intensity changes in dynamic MRI of the subacromial bursa, and confirmed these macroscopically by arthroscopy and histologically. The signal intensity was measured using built-in software, and the enhancement ratio (E ratio) was calculated from dynamic MR images. In addition, as a parameter of the rate of the increase in the signal intensity from 0 to 80 s, the mean increase per second in the E ratio was obtained as the coefficient of enhancement (CE). The correlation was studied of the E ratio and CE with the arthroscopic findings (redness, villous formation, thickening and adhesion), and of the E ratio and CE with the histological findings (capillary proliferation, papillary hyperplasia, fibrosis ...

Energy Technology Data Exchange (ETDEWEB)

Central nervous system (CNS) manifestations in acquired immunodeficiency syndrome (AIDS) patients are an early and common feature. The spectrum of AIDS-related CNS diseases are encephalitis caused by the human immunodeficiency virus(HIV) itself, opportunistic infection, infarct and malignancy. We experienced two cases of CNS involvement in AIDS and they were serologically diagnosed as HIV encephalitis and CNS toxoplasmosis, respectively. In the case of the HIV encephalitis patient, brain MRI showed a non-enhancing lesion with high signal intensity on T2WI and low signal on T1WI and there was no mass effect on the right frontal lobe, periventricular white matter, splenium of the corpus callosum or bilateral basal ganglia. In the other case of CNS toxoplasmosis, MR showed multiple nodular and rim enhanced mass lesions in the right basal ganglia, thalamus and periventricular white matter, which were of low ...

Energy Technology Data Exchange (ETDEWEB)

Several lanthanide shift reagents (LSR) were synthesized from praseodymium, europium, dysprosium, and terbium using ethylenediaminetetraacetic acid, trans-1,2-diaminocyclohexane-N,N,N[prime],N[prime]-tetraacetic acid, and diethylenetriaminepentaacetic acid for the purpose of separating overlapping [sup 31]P FT-NMR spectral signals of dissolved organic phosphorus compounds present in concentrated lake-water samples. The extent of change in signal position and line width of several known phosphorus compounds dissolved in pure water was examined as a function of solution pH and the molar ratio of LSR to phosphorus. Praseodymium ethylenediaminetetraacetate (PrEDTA) was determined to be the most effective LSR. Concentrated lake-water samples mixed with PrEDTA were examined with [sup 31]P FT-NMR. The use of PrEDTA provided separation of overlapping signals, indicated that phosphorus compounds were becoming isolated from the ...

Energy Technology Data Exchange (ETDEWEB)

Rhenium is technetium`s third row congener and exhibits many of the chemical properties that technetium displays. Theoretically, a Re-PhAT complex will be isostructural with the {sup 99m}Tc PhAT complexes that have been prepared for use as brain imaging agents. A series of neutral rhenium(V) oxo complexes was synthesized by the reaction of ReOBr{sub 4}{sup {minus}} with diamino-thiol-thioether ligands of the type (RSC(CH{sub 3}){sub 2})CH{sub 2}NH(o-C{sub 6}H{sub 4})NHCH{sub 2}C(CH{sub 3}){sub 2}SH. The complexes were characterized by IR, UV/visible, and {sup 1}H and {sup 13}C NMR spectroscopy and by fast-atom-bombardment mass spectroscopy. The single-crystal X-ray structure determination on two of the complexes, where R = CH{sub 2}CH{double_bond}CH{sub 2} and CH{sub 2}CH{sub 2}-CH{sub 3}, showed them to consist of a square pyramidal Re{sup V}ON{sub 2}S{sub 2} core. ReO[CH{sub 2}{double_bond}CHCH{sub 2}SC(CH{sub 3}){sub ...

British Library Electronic Table of Contents (United Kingdom)

A novel method of simultaneous realization of optical carrier-suppression and single-sideband modulation using fiber Fabry-Perot tunable filter is presented. In order to enhance transmission performance of radio over fiber links, we use a fiber Fabry-Perot tunable filter to filter out one sideband as well as suppress the optical carrier power. The results demonstrate 20.5dB and 14.2dB improvement in the signal noise ratios when 18GHz and 10GHz microwave signals carrying 5Mbit/s quadrature-phase-shift-keyed (QPSK) format data is transmitted over 35 km single mode fiber, respectively.

British Library Electronic Table of Contents (United Kingdom)

Until recently, the wavelength-division-multiplexed (WDM) transmission system has reached record capacities and distances due to innovations such as FEC (Forward Error Correction), distributed Raman amplification, new transmission fiber and advanced optical format. Optical-communication systems exclusively employed conventional On-Off Keying signals in either Non-Return-To-Zero (NRZ) or Return-To-Zero (RZ) format. Recently a number of advanced modulation formats have attracted attention. Some of these formats carry information through On-Off-Keying but also modulate the optical phase in order to enhance the robustness of signal to chromatic dispersion, optical filtering and non-linearities. Through extensive sets of simulation results, we showed that it is possible to replace a channel wit...

British Library Electronic Table of Contents (United Kingdom)

Here, a general approach for the preparation of reduced graphite oxide (rGO)-silver nanocomposite has been investigated. Graphite oxide (GO) sheets are used as the nanoscale substrates for the formation of rGO-silver composite. GO sheets and Ag ions can be reduced at the same time, under a mild condition using l-ascorbic acid (l-AA) as reducing agent. This simple approach should find practical applications in the production of rGO-silver nanocomposite. The SEM analysis indicates that the silver particles are dispersed on graphene sheets. Raman signals of rGO in the composite are increased by the attached silver nanoparticles, displaying surface-enhanced Raman scattering activity. The degree of enhancement can be adjusted by varying the quantity of silver nanoparticles in the composite. In ...

Energy Technology Data Exchange (ETDEWEB)

An integrated tabu-fuzzy knowledge based controller applied to enhance the performance of power system stabilizer (PSS) is presented in this paper. The fuzzy knowledge based controller (FKBC) has been developed to perform the function of a PSS and to provide a supplementary signal to the excitation system of the synchronous generator. The method used for storing and representing the fuzzy rules is called the fuzzy associative memory (FAM) matrix. The well-defined FAM determines the performance of the FKBC and hence the tabu search algorithm is proposed and applied to determine the construction and optimization of the FAM. The controller has been tested in the case of single machine infinite bus and multi-machine systems for various types of disturbance. To show the effectiveness of the proposed controller, the comparison with the conventional PSS is presented. (author)

Energy Technology Data Exchange (ETDEWEB)

The Linac Coherent Light Source (LCLS) is required to deliver a high quality electron beam for producing coherent X-rays. As a result, high resolution beam position monitoring is required. The Beam Position Monitor (BPM) digitizer acquires analog signals from the beam line and digitizes them to obtain beam position data. Although Matlab is currently being used to test the BPM digitizer?s functions and capability, the Controls Department at SLAC prefers to use Experimental Physics and Industrial Control Systems (EPICS). This paper discusses the transition of providing similar as well as enhanced functionalities, than those offered by Matlab, to test the digitizer. Altogether, the improved test stand development system can perform mathematical and statistical calculations with the waveform signals acquired from the digitizer and compute the fast Fourier transform (FFT) of the signals. Finally, logging of ...

CERN Document Server

An anisotropic power spectrum will have a clear signature in the 21cm radiation from high- redshift hydrogen. We calculate the expected power spectrum of the intensity fluctuations in neutral hydrogen from before the epoch of reionization, and predict the accuracy to which future experiments could constrain a quadrupole anisotropy in the power spectrum. We find that the Square Kilometer Array will have marginal detection abilities for this signal at z~17 if the process of reionization has not yet started; reionization could enhance the detectability substantially. Pushing to higher redshifts and higher sensitivity will allow highly precise (percent level) measurements of anisotropy.

CERN Document Server

An electroweak singlet scalar can couple to pairs of vector bosons through loop-induced dimension five operators. Compared to a Standard Model Higgs boson, the singlet decay widths in the diphotons and Z gamma channels are generically enhanced, while decays into massive final states like WW and ZZ are kinematically disfavored. The overall event rates into gamma gamma and Z gamma can exceed the Standard Model expectations by orders of magnitude. Such a singlet may appear as a resonant signal in the gamma gamma and Z gamma channels, even with a mass above the WW kinematic threshold.

International Nuclear Information System (INIS)

A calculation on the stabilization of the sideband instability in the free electron laser (FEL) and inverse FEL (IFEL) was completed. The issue arises in connection with the use of a tapered (''variable-parameter'') undulator of extended length, such as might be used in an ''enhanced efficiency'' traveling-wave FEL or an IFEL accelerator. In addition, the FEL facility at Columbia was configured as a traveling wave amplifier for a 10-kW signal from a 24-GHz magnetron. The space charge field in the bunches of the FEL was measured. Completed work has been published.

International Nuclear Information System (INIS)

We present a protocol for quantum key distribution using discrete modulation of coherent states of light. Information is encoded in the variable phase of coherent states which can be chosen from a regular discrete set ranging from binary to continuous modulation similar to phase-shift keying in classical communication. Information is decoded by simultaneous homodyne measurement of both quadratures and requires no active choice of basis. The protocol utilizes either direct or reverse reconciliation both with and without postselection. We analyze the security of the protocol and show how to enhance it by the optimal choice of all variable parameters of the quantum signal.

Energy Technology Data Exchange (ETDEWEB)

We investigate the chargino production process {gamma}{gamma} {yields} (W-tilde){sup +}(W-tilde){sup -} at high energy {gamma}{gamma} colliders in the framework of the minimal supersymmetric standard model (MSSM). Here the high energy {gamma} beams are obtained by the backward Compton scattering of the laser flush by the electron in the basic linear TeV ee colliders. We consider the polarization of the laser photons as well as the electron beams. Appropriate beam polarization could be effective to enhance the cross section to for us extract the signal from the dominant background {gamma}{gamma} {yields} W{sup +}W{sup -}. (author).

Energy Technology Data Exchange (ETDEWEB)

System instability as result of high power generation of one of the largest plants of the Iranian electric power grid prevented the plant to be fully utilized. PSSs were installed on the generating units of the power station, to improve its small signal stability, and enhance the stable generation limit. Domain separation and pole assignment techniques were applied for the PSS design. Several field tests were also carried out to verify its effectiveness. This paper presents the PSS tuning procedure, including the design criteria and some of the field test results.

Energy Technology Data Exchange (ETDEWEB)

Objective. To compare turbo inversion recovery magnitude (TIRM) with standard T1-weighted (T1-W) and T2-weighted (T2-W) MR sequences in the very early detection of acute osteomyelitis in children. Materials and methods. In 15 children with osteomyelitis, 15 sets of T1-W spin-echo (SE) (TR/TE, 400-640/12-17), T2-W turbo spin-echo (TSE) (TR/TE/ETL, 3290-4465/112-120/11), and TIRM (TR/TE/TI, 4000-6120/60/160) images were acquired with a 1.0-T magnet. Contrast-to-noise (C/N) ratios and percentage of signal between lesion and normal bone marrow were analysed with a computer-assisted image analysing system in a region of interest (ROI). Results. In 13 of 15 patients, the absolute signal enhancement in a ROI on the TIRM images was better than on the T1-W SE and T2-W TSE images and in 14 of 15 cases, C/N ratios were also better on the TIRM images than on the other sequences. In the other cases, the TIRM signal ...

Science.gov (United States)

The effect of reference signals on performance in a visual vigilance task was studied under three conditions. Reference signals were presented on the same display as the real signals. In condition 1 (control), no reference signals were displayed. Sugbject...

International Nuclear Information System (INIS)

In the present paper we estimate the effect of sodium in the in-service inspection of non-magnetic steam generators tubes using eddy current technique and eddy current probes based on a differential double bobbin coil configuration. Experimental measurements of defects signals in steam generator tubes of fast breeder reactor are compared with simulations results of a two-dimensional axisymmetric finite element code to validate a reliable electromagnetic model of the system (eddy current coils, steam generator tube, defect) when there is no sodium on the outer steam generator tube surface. The electromagnetic code is used to evaluate the sodium band and sodium layer signals when a defect is located under steam generator support plate. Using a multi-frequency algorithm, its parameters are determined in the 'no sodium condition' (there is no sodium on the outer steam generator tube surface), defects signal is ...

Science.gov (United States)

The present work reports on Raman and Surface Enhanced Raman Scattering (SERS) vibrational fingerprints of ?-carotene and haemoglobin in fresh whole blood (i.e. right after blood test) with different laser excitations, i.e. visible (514 nm) and near-infrared (NIR, 785 nm). The use of colloidal silver nanoparticles significantly increases the Raman signal, thus providing a clear SERS spectrum of blood. The collected spectra have been examined and marker bands of ?-carotene and of the haem prosthetic group of haemoglobin have been found. In particular, the fundamental features of ?-carotene (514 nm excitation), blood proteins and haem molecules (785 nm excitation) were recognized and assigned. Moreover haemoglobin SERS signals can be identified and related with its oxygenation state (oxy-haemoglobin). The data reported show the prospects of Raman and SERS techniques to detect important bio-molecules in a whole blood sample ...

International Nuclear Information System (INIS)

The Loose Parts Monitoring System (LPMS) provides information on the location of a loosened or detached metal impacted onto the inner surface of a primary pressure boundary and on a mass or energy of the impact signal. For the conventional system, it is popular to employ the group delay among the sensors installed within 3 ft range from the impact source in a collection zone as stated in the Reg. Guide 1.133. However, there exist inherent errors for the estimation of the true location of the impact since it is highly dependent on the plant personnel's decision to determine the arrival time differences of the generated wave group among the neighbouring sensors. To overcome this problem in this study, the two-dimensional approach has been proposed and applied to effectively estimate the arrival time differences of the impact signal by using continuous wavelet transform which is one of the linear time-frequency analysis methods. The experiment has ...

British Library Electronic Table of Contents (United Kingdom)

A promising drug target currently under investigation to improve cognitive deficits in neuropsychiatric and neurological disorders is the neuronal nicotinic alpha7 acetylcholine receptor (a7nAChR). Improving cognitive impairments in diseases such as Alzheimer's (AD) and schizophrenia remains a large unmet medical need, and the a7nAChR has many properties that make it an attractive therapeutic target. The a7nAChR is a ligand gated ion channel that has particularly high permeability to Ca^2^+ and is expressed in key brain regions involved in cognitive processes (e.g., hippocampus). The a7nAChRs are localized both pre-synaptically, where they can regulate neurotransmitter release, and post-synaptically where they can activate intracellular signaling cascades and influence downstream processes...

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Stress chemiluminescence (SCL) is a novel technique for monitoring aging reactions of polymeric materials under stress. A special apparatus for detecting the chemiluminescence of solid polymers has been designed and built. There is a correlation between an enhanced chemiluminescence signal at low levels of applied stress and subsequent premature mechanical failure of samples of tetraglycidyl-4,4'-methylenedianiline (TGMDA) cured with 4,4'-diaminodiphenyl sulfone (DDS) the most commonly used epoxy in high performance fiber composites. Chemiluminescence data from silicone cushions is used to validate accelerated aging tests and preliminary results from Kevlar fibers are reported. The technique will be extended to other polymeric materials including fiber composites. 22 references, 7 figures, 1 table.

CERN Document Server

A new calculation of the $\\bar{p}/p$ ratio in cosmic rays is compared to the recent PAMELA data. The good match up to 100 GeV allows to set constraints on exotic contributions from thermal WIMP dark matter candidates. We derive stringent limits on possible enhancements of the WIMP \\pbar flux: a $m_{\\rm WIMP}$=100 GeV (1 TeV) signal cannot be increased by more than a factor 6 (40) without overrunning PAMELA data. Annihilation through the $W^+W^-$ channel is also inspected and cross-checked with $e^+/(e^-+e^+)$ data. This scenario is strongly disfavored as it fails to simultaneously reproduce positron and antiproton measurements.

International Nuclear Information System (INIS)

Sixty-three subjects, aged 6 months to 16 years, who were enrolled in a prospective, fully blinded, randomized parallel-group phase III clinical trial, received 0.1 mmol/kg doses of either Gd-BOPTA (n=29) or Gd-DTPA (n=34). The MR images were acquired before and within 10 min of contrast agent injection. The primary objective was to compare the difference from pre-dose to post-dose lesion visualization between Gd-BOPTA and Gd-DTPA. Lesion visualization was determined as the sum of individual scores for three criteria of lesion morphological characteristics (lesion border delineation, internal morphology, and contrast enhancement), each assessed qualitatively using 4-point scales. Quantitative evaluation compared changes in lesion-to-background (LBR) and contrast-to-noise (CNR) ratios and per cent enhancement. Monitoring for adverse events and evaluation of vital signs and laboratory values was performed. Pre-dose to post-dose changes in lesion ...

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CERN Document Server

Negative frequency has a physical meaning, the complete description of a frequency signal is a rotating complex signal, in complete description, positive frequency signal exp(iwt) and negative frequency signal exp(-iwt) is two distinguishable and independent frequency signals. Because the real-carrier modulation and demodulation do not distinguish positive and negative frequency, so half of the spectrum resources and signal energy are wasted. The complex-carrier modulation uses the distinguishable positive frequency signal exp(iwt) and negative frequency signal exp(-iwt) as the carrier signals, they can carry different information, so the spectrum resources is full used, the complex-carrier demodulation does not lose signal energy, so the spectrum efficiency is improved.

International Nuclear Information System (INIS)

Object: To smoothly control automatic water supply for realizing stable operation of a nuclear reactor by providing a flow rate limiting signal selection circuit and a preferential circuit in a water supply control device for a nuclear reactor wherein the speed of a recirculation pump may be changed in two-steps. Structure: Opening angle signals for a water supply regulating valve are controlled by a nuclear reactor water level signal, a vapor flow rate signal and a supplied water flow rate signal through an adder and an adjuster in response to a predetermined water level setting signal. When the water in the reactor is maintained at a predetermined level, a selection circuit receives a water pump condition signal for selecting one of the signals from a supplied water rate limiting signal generator ...

Science.gov (United States)

Myostatin is a member of the transforming growth factor-{beta} (TGF-{beta}) family and a strong negative regulator of muscle growth. Here, we present the crystal structure of myostatin in complex with the antagonist follistatin 288 (Fst288). We find that the prehelix region of myostatin very closely resembles that of TGF-{beta} class members and that this region alone can be swapped into activin A to confer signalling through the non-canonical type I receptor Alk5. Furthermore, the N-terminal domain of Fst288 undergoes conformational rearrangements to bind myostatin and likely acts as a site of specificity for the antagonist. In addition, a unique continuous electropositive surface is created when myostatin binds Fst288, which significantly increases the affinity for heparin. This translates into stronger interactions with the cell surface and enhanced myostatin degradation in the presence of either Fst288 or Fst315. Overall, we have identified ...

International Nuclear Information System (INIS)

The MRI and CT appearances in 48 patients with histologically confirmed benign and malignant pleural abnormalities were compared retrospectively. Abnormal pleural changes were shown in 47 out of the 48 patients by high signal intensity of the pleura in T_2-weighted sequences and in contrast enhanced T_1-weighted sequences on MRI. CT showed abnormalities in 45 out of 48 patients. Delineation of pleural and pulmonary changes by CT was possible in 13 out of 23 cases, and pleural disease from effusions in 15 out of 28 cases. T_2-weighted MRI was successful in 14 out of 23 and 4 out of 28 cases, respectively. T_1-weighted images after contrast were successful in 20 out of 23 and 22 out of 28 cases, respectively. Indications of malignant pleural disease were the presence of mediastinal or circumferential involvement or involvement of the entire pleura, thickness of more than 10 mm and nodular changes. The most reliable sign of malignancy was ...

CERN Document Server

If the first (PopIII) stars were very massive, their final fate is to collapse into very massive black holes. Once a proto-black hole has formed into the stellar core, accretion continues through a disk. It is widely accepted, although not confirmed, that magnetic fields drive an energetic jet which produces a burst of TeV neutrinos by photon-meson interaction, and eventually breaks out of the stellar envelope appearing as a Gamma Ray Burst (GRB). Based on recent numerical simulations and neutrino emission models, we predict the expected neutrino diffuse flux from these PopIII GRBs and compare it with the capabilities of present and planned detectors as AMANDA and IceCube. If beamed into 1% of the sky, we find that the rate of PopIII GRBs is $\\le 4 \\times 10^6$ yr$^{-1}$. High energy neutrinos from PopIII GRBs could dominate the overall flux in two energy bands [$10^4 - 10^5$] GeV and [$10^5 - 10^6$] GeV of neutrino telescopes. The enhanced sensitivities of ...

CERN Document Server

Anti-proton and positron Galactic cosmic ray (GCR) spectra are among the key targets for indirect detection of dark matter (DM). The boost factors, corresponding to an enhancement of the signal|linked to the clumpiness properties of the dark matter distribution|, have been taken as high as thousands in the past. The dramatic impact of these boost factors for indirect detection of antiparticles, for instance with the PAMELA satellite or the coming AMS-02 experiment, asks for their detailed calculation. We take into account the state-of-the-art results of high resolution N-body dark matter simulations to calculate the most likely energy dependent boost factors|linked to the GCR propagation properties|, for anti-protons and positrons. The results from extreme, but still possible, configurations of the clumpy dark matter component is also discussed. Starting from the mass and space distributions of sub-halos, the anti-proton and positron ...

Energy Technology Data Exchange (ETDEWEB)

The mission of the Emerging Technologies thrust area at Lawrence Livermore National Laboratory is to help individuals establish technology areas that have national and commercial impact, and are outside the scope of the existing thrust areas. We continue to encourage innovative ideas that bring quality results to existing programs. We also take as our mission the encouragement of investment in new technology areas that are important to the economic competitiveness of this nation. In fiscal year 1992, we have focused on nine projects, summarized in this report: (1) Tire, Accident, Handling, and Roadway Safety; (2) EXTRANSYT: An Expert System for Advanced Traffic Management; (3) Odin: A High-Power, Underwater, Acoustic Transmitter for Surveillance Applications; (4) Passive Seismic Reservoir Monitoring: Signal Processing Innovations; (5) Paste Extrudable Explosive Aft Charge for Multi-Stage Munitions; (6) A Continuum Model for Reinforced Concrete at High Pressures and ...

Science.gov (United States)

This paper proposes a new pattern recognition system employing optical joint transform correlation (JTC) technique which offers a great number of advantages over similar digital techniques, including very fast operation, simple architecture and capability of updating the reference image in real time. The proposed JTC technique incorporates a synthetic discriminant function (SDF) of the target image estimated from different training images to make the pattern recognition performance invariant to noise and distortion. It then involves four different phase-shifted versions of the same target SDF reference image, which are individually joint transform correlated with the given input scene. When the correlation signals are combined, it produces a single cross-correlation peak corresponding to each potential target present in the given input scene. The proposed technique also includes a fringe-adjusted filter to generate a delta-like correlation peak with high ...

British Library Electronic Table of Contents (United Kingdom)

Genome-wide association studies have linked lung cancer risk with a region of chromosome 15q25.1 containing CHRNA3, CHRNA5 and CHRNB4 encoding a3, a5 and b4 subunits of nicotinic acetylcholine receptors (nAChR), respectively. One of the strongest associations was observed for a non-silent single-nucleotide polymorphism at codon 398 in CHRNA5. Here, we have used pharmacological (antagonists) or genetic (RNA interference) interventions to modulate the activity of CHRNA5 in non-transformed bronchial cells and in lung cancer cell lines. In both cell types, silencing CHRNA5 or inhibiting receptors containing nAChR a5 with a-conotoxin MII exerted a nicotine-like effect, with increased motility and invasiveness in vitro and increasing calcium influx. The effects on motility were enhanced by addit...

International Nuclear Information System (INIS)

The purpose of this study is to evaluate the radiologic findings of the extraosseous Ewing's sarcoma. Six patients with pathologically confirmed extraosseous Ewing's sarcoma were retrospectively reviewed. Patients included two men and four women with an average age of 21.5 years (age range 9-48 years). Plain radiographs (six patients), magnetic resonance (MR) images (five patients), computed tomographic (CT) scans (three patients) and whole body scintigraphy (two patients) were reviewed and analyzed. Images were evaluated with regard to lesion location, size, margin, muscle or bone involvement and intrinsic imaging characteristics on CT and MRI. The tumors were located in the thigh (three patients), back (two patients) and upper arm (one patient). The tumors ranged in size from 2.3 cm to 7.5 cm (mean, 5.2 cm), were mainly well circumscribed and showed no evidence of calcification prior to treatment. Margins were well defined in four out of the six patients. Four patients had ...

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The R and D were carried out of a detecting system for measurement of data on the bottom of geothermal well, data transmission and signal processing, and an analysis system for well drilling trajectory control and well assessment while geothermal well drilling based on the data obtained by the detecting system. The paper reported the results of the technology development in fiscal 1996. In the development of the detecting system, improvement/design were conducted on a mud pulse generator constituting sonde, well bottom signal processing equipment, mode switch and inclined information sensor, and the system equivalent to the actual one was manufactured to conduct a running test at high temperature/pressure. Moreover, a test to confirm heat resistance of electronic parts was made for further improvement in heat resistance of the sonde, in order to obtain the data. In the development of an analysis system, conducted were ...

CERN Document Server

Control of Phosphorus Transient Enhanced Diffusion using Co-implantation

UK PubMed Central (United Kingdom)

Sexually-selected communication signals can be used by competing males to settle contests without incurring the costs of fighting. Steroid regulation of these signals can render them as reliable...Full Text Available

UK PubMed Central (United Kingdom)

Colour television is examined as an attempt to imitate the human visual system in image formation, spectral sensitivities, adaptation, contrast effects, signal processing, signal modulation, signal...Full Text Available

Science.gov (United States)

An electronic computer circuit is described for producing an output voltage proportional to the product or quotient of tbe voltages of a pair of input signals. ln essence, the disclosed invention provides a computer having two channels adapted to receive separate input signals and each having amplifiers with like fixed amplification factors and like negatlve feedback amplifiers. One of the channels receives a constant signal for comparison purposes, whereby a difference signal is produced to control the amplification factors of the variable feedback amplifiers. The output of the other channel is thereby proportional to the product or quotient of input signals depending upon the relation of input to fixed signals in the first mentioned channel.

UK PubMed Central (United Kingdom)

Sensory systems must form stable representations of the external environment in the presence of self-induced variations in sensory signals. It is also possible that the variations themselves may provide...Full Text Available

UK PubMed Central (United Kingdom)

Animal communication theory predicts that low-frequency cheating should be common in generally honest signalling systems. However, perhaps because cheats are designed to go undetected, there are few...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundAmino-terminal signal peptides (SPs) are short regions that guide the targeting of secretory proteins to the correct subcellular compartments in the cell. They are cleaved...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Background. In multiple myeloma 5 different infiltration patterns can be differentiated: 1. Normal appearance of bone marrow, 2. focal involvement, 3. homogeneous diffuse infiltration, 4. combined diffuse and focal infiltration, 5. 'salt-and pepper' pattern with inhomogeneous bone marrow with interposition of fat islands. Methods. For the fast and total acquisition of all patterns a combination of a T1-weighted spin echo sequence and a fat suppression technique is superior. The focal involvement is clearly demonstrated as areas of high signal intensity on e.g. STIR images. Diffuse involvement can be quantified objectively by calculation of the percentage of signal intensity increase after contrast material injection. MRI is superior to X-ray in focal and diffuse involvement. With ultrafast sequences a 'screening' of the whole red bone marrow as for myeloma infiltration is possible. Prognosis. In prognosis ...

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International Nuclear Information System (INIS)

The paper considered the vibration signals of rotating equipment as cyclo stationary signals through analyzing the features of this kind of signals. Based on the analytic method of cyclic spectrum density, the paper pointed out that the impact frequency could be extracted effectively with the help of scanning cyclic frequency domain. The validity of the method of cyclic spectrum density is proved by simulating signals and the method is applied to the diagnosis of rolling bearings. (authors)

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...of the and global warming signal so ...

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The differences are highlighted of various aspects of behaviour of the luminescence signal from feldspar when stimulated by green light and when stimulated by infrared radiation. In respect of bleaching, a comparison is made of the influence of white light (daylight) on the two stimulated luminescence signals, as well as a comparison of the influence of infrared exposure on the green-stimulated signal with the influence of green exposure on the infrared-stimulated signal. The influence of preheating on the two stimulated signals is also compared. Light-emitting diode systems were used for both green and infrared stimulation. The observations are considered in relation to the mechanism relevant to green- and infrared-stimulated luminescence from feldspar. (author).

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We present a case of cerebral aspergillosis in an immunocompetent patient. The MRI signal characteristics were compared with the histologic findings. Irregular low-signal zones were demonstrated between the wall of the abscess and the central necrosis on T2-weighted images; the pathology specimen revealed concentrated iron in these transitional zones but no hemosiderin. Iron is an essential element for the growth of fungal hyphae. The low-signal zones may represent the areas where there was active proliferation of aspergillus, and the unique location of the low signal may be a helpful imaging characteristic for the diagnosis of an aspergillus abscess. (orig.)

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Introduction: The goal of this study was to compare contrast-enhanced T1-weighted Flash and Turbo-Flash sequences with conventional spin-echo sequences as a basis for planning high-precision radiotherapy. Methods: A total of 25 consecutive patients with different intracranial tumors and a disrupted blood-brain barrier were studied. T1-weighted Flash, Turbo-Flash and conventional spin-echo images were evaluated after controlled 30-s infusion of 0.1 mmol/kg body weight of Gd-DTPA. The evaluation of the three sequences included the measurement of the signal- and contrast-to-noise ratios, the visual inspection of the tumors and artifacts, and the measurement of tumor size. Results: The signal- and contrast-to-noise ratios were significantly (P<0.05-0.01) lower for Flash and Turbo-Flash than for conventional spin-echo sequences. However, visual inspection of the contrast-enhancing tumors revealed in 23 ...

Science.gov (United States)

... Accession Number : ADD335251. Title : Multiple-Element Eddy Current Probes for Enhanced Inspection,. Corporate Author : ...

Science.gov (United States)

The generalized demodulation time-frequency analysis is a novel signal processing method, which is particularly suitable for the processing of multi-component amplitude-modulated and frequency-modulated (AM-FM) signals as it can decompose a multi-component signal into a set of single-component signals whose instantaneous frequencies own physical meaning. While fault occurs in gear, the vibration signals measured from gearbox would exactly display AM-FM characteristics. Therefore, targeting the modulation feature of gear vibration signal in run-ups and run-downs, a fault diagnosis method in which generalized demodulation time-frequency analysis and envelope order spectrum technique are combined is put forward and applied to the transient analysis of gear vibration signal. Firstly the multi-component vibration signal of ...

UK PubMed Central (United Kingdom)

The realization that there existed a G-protein coupled signal transduction mechanism developed gradually and was initially the result of an ill fated quest for uncovering the mechanism of action...Full Text Available

UK PubMed Central (United Kingdom)

Cilia are important cellular structures that have been implicated in a variety of signaling cascades. In this review, we discuss the current evidence for and against a link between cilia and both the...Full Text Available

UK PubMed Central (United Kingdom)

Taste cells use multiple signaling mechanisms to generate appropriate cellular responses to discrete taste stimuli. Some taste stimuli activate G protein coupled receptors (GPCRs) that cause calcium...Full Text Available

UK PubMed Central (United Kingdom)

In this study we compared the molecular signalling elicited by rexinoids, selective retinoid X receptor (RXR)-activators, in several organs (i.e. liver, kidney,...Full Text Available

UK PubMed Central (United Kingdom)

During the past decade elevated phospholipase D (PLD) activity has been reported in virtually all cancers where it has been examined. PLD catalyzes the hydrolysis of phosphatidylcholine to generate...Full Text Available

UK PubMed Central (United Kingdom)

An optical flow gradient algorithm was applied to spontaneously forming networks of neurons and glia in culture imaged by fluorescence optical microscopy in order to map functional calcium signaling...Full Text Available

UK PubMed Central (United Kingdom)

Host cells use metabolic signaling through the LXRα nuclear receptor to defend against Listeria monocytogenes infection. 25-Hydroxycholesterol is a natural ligand of LXRs that...Full Text Available

UK PubMed Central (United Kingdom)

Hematopoiesis is the cumulative result of intricately regulated signaling pathways that are mediated by cytokines and their receptors. Studies conducted over the past 10 to 15 years have revealed that...Full Text Available

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The receptors for IGF-I (IGF-IR) and insulin (IR) have been implicated in physiological cardiac growth, but it is unknown whether IGF-IR or IR signaling are critically required. We generated mice with...Full Text Available

UK PubMed Central (United Kingdom)

IntroductionTyrosine phosphorylated signal transducer and activator of transcription 3 (pStat3) is expressed in numerous cancers and is required for mediating tumorigenesis. Autocrine...Full Text Available

UK PubMed Central (United Kingdom)

Experimental studies have demonstrated that not only dopaminergic signaling but also glutamatergic/NMDA receptor signaling play indispensable roles in the development of methamphetamine psychosis. Our...Full Text Available

UK PubMed Central (United Kingdom)

Predation is generally thought to constrain sexual selection by female choice and limit the evolution of conspicuous sexual signals. Under high predation risk, females usually become less choosy, because...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Airbag pressure vessels for the north-American market mainly are made by forging and by the use of steel alloys. In Europe aluminum alloys are common and the manufacturing process is extrusion of circular blanks - made from cold rolled plates - in a form applying a 100 t press at room temperature. Then by heat treatment the strength/hardness of the material is properly adjusted and after that the pressure vessel parts have to be continuously inspected with an inspection and handling cycle time of 3 s. Inspection of the axis-symmetric parts is asked for surface breaking extrusion defects as well as for surface parallel delaminations in the bulk volume. Furthermore, the material strength is a quality characteristic that has to be nondestructively registered and documented. The inspection is performed by eddy current probes and an EMAT, of which the eddy current impedance measurements are used for surface breaking extrusion defect detection and sizing (single frequency technique with ...

Science.gov (United States)

In 1999, RECONS (Research Consortium on Nearby Stars) began gathering astrometric data using the CTIO 0.9m under the auspices of the NOAO Surveys Program. In 2003, SMARTS began operating the 0.9m and the program continued, with an enhanced ability to acquire long-term astrometric series on the nearest stars. With over a decade of milli-arcsecond astrometry for hundreds of red dwarfs within 25 pc, we now have a rich dataset in which to search for previously unknown stellar, substellar, and planetary companions. We can also use our data to better constrain the orbits of known binaries to reduce their mass errors to less than a few percent, and consequently test astrophysical models as never before. Here we present our orbit fitting analysis of M dwarfs that show clear evidence of gravitational perturbations due to unseen companions, after solving for their proper motion and parallax signals. We show discoveries such as LHS 3738AB, found for the ...

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January, 1992, to October, 1995, sixty-four patients with advanced head and neck cancer underwent head and neck reconstructive surgery using myocutaneous or revascularized flaps; in the same period, all patients were consecutively examined with CT and MRI. Myocutaneous flaps were used in 26 patients: 12 flaps were tubular and 14 linear. Revascularized flaps were used in 38 patients: to repair a large defect in 26 patients (14 latissimus dorsi flaps and 12 temporal muscle flaps) and to repair an oral damage in 12 patients (5 revascularized radial and 7 jejunal flaps). CT and MR images of myocutaneous flaps showed the flaps as fatty areas, repairing large surgical defects, hypodense at CT and hyperintense at MRI, with no post-contrast enhancement. The appearance of revascularized flaps at CT and MRI depends on the characteristics of the structure used to repair the surgical defect: jejunal and radial flaps appeared as mostly fatty thickened layers with both imaging ...

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OF VOCALIZED SPEECH THROUGH. ANALYSIS OF NEURAL SIGNALS. " SYNTHETIC TELEPATHY- WIRELESS. TRANSMISSION OF DECODED. THOUGHTS. " IMPLANTABLE MEMORY-ELIMINATES ...

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Until April 2007 the Major Atmospheric Gamma ray Imaging Cherenkov (MAGIC) telescope used a 300 MSamples/s flash analog-to-digital converter (FADC) system to sample the shaped photomultiplier tube (PMT) signals produced by the captured Cherenkov photons of air showers. Different algorithms to reconstruct the signal from the read-out samples (extractors) have been implemented and are described and compared. Criteria based on the obtained charge and time resolution/bias are defined and used to judge the different extractors, by applying them to calibration, cosmic and pedestal signals. The achievable charge and time resolution have been derived as functions of the number of incident photo-electrons.

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... measurement. Power spectral density measurements are made by the dynamic signal analyzer for each channel. A cross power ...

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In embodiments, spectroscopic monitor monitors modulated light signals to detect low levels of contaminants and other compounds in the presence of background interference. The monitor uses a spectrometer that includes a transmissive modulator capable of causing different frequency ranges to move onto and off of the detector. The different ranges can include those with the desired signal and those selected to subtract background contributions from those with the desired signal. Embodiments of the system are particularly useful for monitoring metal concentrations in combustion effluent.

CERN Document Server

We obtain a simple derivation of the optimal quantum state estimation of a two-level system using the no-signaling principle. In particular, we show that the no-signaling principle determines the unique form of the guessing probability, independently to a given figure of merit such as the fidelity or the information gain. This proves that optimal measurements for a two-level quantum system is the same for almost all figures of merit.

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The vigilance reinforcement hypothesis (VRH) asserts that errors in signal detection tasks are partially explained by operant reinforcement and extinction processes. VRH predictions were tested with a computerized baggage screening task. Our experiment evaluated the effects of signal schedule (extinction vs. variable interval 6 min) and visual field complexity (dial vs. baggage x-ray) on search behavior rates. There was a main effect for signal schedule [F (1, 20) = 14.0, p = 0.001, p[subscript rep] = 0.99], but no effects for field complexity or interaction. The VRH suggests that performance errors in visual screening work may be reduced through operant conditioning of search behaviors by intensive management of artificially planted signals. (Contains 1 table and 3 figures.)

UK PubMed Central (United Kingdom)

Using a ligature-induced model in type-2 Zucker diabetic fatty (ZDF) rat and normoglycemic littermates, we investigated whether diabetes primarily affects periodontitis by enhancing bone loss...Full Text Available

Science.gov (United States)

The purpose of this study was to develop a simple motion measurement system with magnetic resonance (MR) compatibility and safety. The motion measurement system proposed here can measure 5-DoF motion signals without deteriorating the MR images, and it has no effect on the intense and homogeneous main magnetic field, the temporal-gradient magnetic field (which varies rapidly with time), the transceiver radio frequency (RF) coil, and the RF pulse during MR data acquisition. A three-axis accelerometer and a two-axis gyroscope were used to measure 5-DoF motion signals, and Velcro was used to attach a sensor module to a finger or wrist. To minimize the interference between the MR imaging system and the motion measurement system, nonmagnetic materials were used for all electric circuit components in an MR shield room. To remove the effect of RF pulse, an amplifier, modulation circuit, and power supply were located in a shielded case, which was made ...

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The high spatial resolution of state-of-the-art commercial satellite imagery provides a good basis for recognising and monitoring even small-scale structural changes within nuclear facilities and for planning of routine and/or challenge inspections of nuclear sites. Despite the advantages of the improved spatial resolution some problems exist that may make the interpretation of the changes more difficult: Firstly, the results of the change analysis can be very complex and unclear at a glance. Secondly, shadow formation and off-nadir images due to different sensor and solar conditions at the acquisition times can cause false signals or overlap real changes. In view to the fast-growing amount of data from different sensor types there are then some requirements of an effective change detection procedure for safeguards purposes: i. The techniques involved should possess a certain amount of robustness in terms of small misregistration errors, different atmospheric ...

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Norwegian Open Research Archives (NORA)

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Short communication

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The influence of low-frequency electromagnetic field irradiating by high-voltage transmission lines on signal transduction of cell in spleen cells of the rates have been studied by molecular-biology techniques. The spleen cells are extracted from skilled rates, which are exposed in the electromagnetic field of high-voltage transmission lines with 4000 V/m and 0.09-0.1 G about 400 days. The quantity or level of phosphorylation of signal transducer and activator of transcription (STAT3) in JAK-STAT signal transduction pathway of spleen cells, which are stimulated and unstimulated by IL-2, respectively, are detected by the immunoblotting and immunobiochemistry. The results show that the expression of phospho-STAT3 in spleen cell stimulated by IL-2 differ not from that in the unstimulated cell. The former is significantly large than the latter. This shows that signal transduction of cell is affected by this ...

Science.gov (United States)

Functional activation of {beta}-catenin/Tcf signaling plays an important role in early events in carcinogenesis. We examined the effect of naringenin against {beta}-catenin/Tcf signaling in gastric cancer cells. Reporter gene assay showed that naringenin inhibited {beta}-catenin/Tcf signaling efficiently. In addition, the inhibition of {beta}-catenin/Tcf signaling by naringenin in HEK293 cells transiently transfected with constitutively mutant {beta}-catenin gene, whose product is not phosphorylated by GSK3{beta}, indicates that its inhibitory mechanism was related to {beta}-catenin itself or downstream components. To investigate the precise inhibitory mechanism, we performed immunofluorescence, Western blot, and EMSA. As a result, our data revealed that the {beta}-catenin distribution and the levels of nuclear {beta}-catenin and Tcf-4 proteins were unchanged after naringenin treatment. Moreover, the ...

International Nuclear Information System (INIS)

Objective: To compare the efficiency of dual energy subtraction and conventional direct digital radiography in signal detecting ability. Methods: 200 plastic balls which were 4 mm in diameter were taken as signals and were placed on a 10 cm thick plastic board and the right upper thorax of a healthy volunteer. The signals were examined by DES and CDR separately and were estimated by 3 radiologists with 5-value-differentiation method. ROC curve analysis was made by ROC kit software. Results: when signals on plastic board were detected by CDR and DES, ROC curve analysis indicated that there was no significant difference (P=0.4851 > 0.05, two-tailed) between the area under the ROC curves of the two methods (Az=0.9931 for CDR and Az=0.9879 for DES). The difference was significant (P=0.0002 <0.01, two-tailed) between the area under the ROC curves of CDR and DES (Az=0.7276 for CDR and Az=0.8561 for ...

Science.gov (United States)

Enhanced heat transfer in curved rectangular channels depends on at least two geometric factors, the radius of curvature of the duct and the aspect ratio, which is the width/depth ratio of the duct. In this work, an expression for optimum aspect ratio is derived mathematically from a correlation that includes both aspect ratio and bend curvature parameters. Enhancement factors are developed that show optimal, near-optimal, and nonoptimal aspect ratios for curved rectangular ducts. Predicted enhancements are within 25% of published literature results for individual designs, two of which show heat transfer enhancement of 200% over that of a straight duct with turbulent flow. The theoretical maximum enhancement is shown to be about 480% over a straight-duct, turbulent-flow situation. This is not achievable in practice, but near-optimal solutions are achievable, yielding ...

Energy Technology Data Exchange (ETDEWEB)

This paper describes a signal simulator which is designed to calibrate eddy current probes. By using simultaneously an excitation coil and an electrically conducting plane, the simulator can emulate signals which correspond to spot welds with different flaws. The presence of a conducting plane allows a wide variation of the amplitude and phase of the excitation coil voltage during the calibration of a probe. A mathematical model for the simulator is derived and used to study the variation of the impedance change upon the parameters of the probe. Numerical computation shows that the impedance change depends in an important way on the frequency of the excitation coil current.

International Nuclear Information System (INIS)

A computerised glow curve deconvolution (CGCD) analysis was applied to the main dosimetric peak of #alpha#-Al_2O_3:C in order to study the effects of light on the glow curve shape. It was shown that both the light-induced signal and the light-induced fading effects tend to shift the main dosimetric peak to higher temperatures and at the same time change its shape. Furthermore it was confirmed that the magnitude of the light-induced signal depends on radiation history and, by increasing the duration of light exposure, the magnitude of the light-induced signal reaches a plateau, thereby implying the saturation of the phototransfer process. (author).

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A confocal microscopy imaging system was devised to selectively detect Second harmonic signals generated by biological tissues. Several types of biological tissues were examined using this imaging system, including human teeth, bovine blood vessels, and chicken skin. All these tissues generated strong second harmonic signals. There is considerable evidence that the source of these signals in tissue is collagen. Collagen, the predominant component of most tissues, is known to have second order nonlinear susceptibility. This technique may have diagnostic usefulness in pathophysiological conditions characterized by changes in collagen structure including malignant transformation of nevi, progression of diabetic complications, and abnormalities in wound healing.

International Nuclear Information System (INIS)

The Bragg-curve detector of the parallel plate ionization chamber type generates a signal that is a distorted replica of the original Bragg-curve. In result of this distortion, the signal peak height is not only a function of the atomic number of the heavy ion, as it is often stated, but also of the particle mass. This mass effect was studied with the aid of computer simulation, and it was found to be dependent on the Frisch grid to anode gap width and on the detector gas. The charge resolution of the detector is affected very significantly by this mass dependence of the signal peak height. Therefore, a careful selection of the detector gas and the grid to anode gap width is necessary, if good charge resolution over a wide range of heavy ions is required. (orig.).

UK PubMed Central (United Kingdom)

Humans, like other animals, are exposed to a continuous stream of signals, which are dynamic, multimodal, extended, and time varying in nature. This complex input space must be transduced and sampled...Full Text Available

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... Defense. ... 6 Specific restrictions are outlined in US Signals Intelligence Directive (USSID) 18 and DoD Regulation 5240.1-R. 7 House ...

International Nuclear Information System (INIS)

We argue that the tachyons which exist in some string models are a signal of deconfinement. We compare the deconfinement temperature obtained from Monte Carlo calculations with some string models. (orig.).

Science.gov (United States)

R/V Laurence M. Gould LMG0303 - Development of a luminescence dating capability for Antarctic glaciomarine sediments: Tests of signal zeroing at the ...

Science.gov (United States)

... lasers, model switched optical memory elements ... Optical RS flip flop, Acousto-optic switches. ... FLOP CIRCUITS, OPTICAL SWITCHING, NOR GATES ...

International Nuclear Information System (INIS)

Although infrared-stimulated luminescence (IRSL) signals in feldspars can be bleached rapidly by sunlight, there could still be a small amount of IRSL signal remaining in sediment grains if they have experienced only relatively short sunlight exposure before deposition. This remaining signal results in a ''remnant dose'' stored in the grain and is important for young samples but negligible for old samples. Several methods have been introduced to detect insufficient bleaching, and some of them can provide information on the extent of the bleaching. Others can only distinguish between samples bleached for a very long time and for a short time. Empirical methods are introduced to evaluate the possible values of equivalent dose accumulated since the grains were deposited. These methods involve the analysis of the equivalent doses and the natural IRSL signals obtained using single-disc dose determination ...

UK PubMed Central (United Kingdom)

Diverse cell polarity networks require positive feedback for locally amplifying distributions of signalling molecules at the plasma membrane1. Additional...Full Text Available

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The KDP crystal was 10 cm long and cut such that the c-axis was 50.3* to the normal of its input face. We selected for study idler and signal beams ...

International Nuclear Information System (INIS)

... for mediating the effects of early adverse experiences since they are affected

British Library Electronic Table of Contents (United Kingdom)

Fibroblast growth factor (FGF) signaling has been shown to regulate lung epithelial development but its influence on mesenchymal differentiation has been poorly investigated. To study the role of mesenchymal FGF signaling in the differentiation of the mesenchyme and its impact on epithelial morphogenesis, we took advantage of Fgfr2c+/? mice, which due to a splicing switch express Fgfr2b in mesenchymal tissues and manifest Apert syndrome-like phenotypes. Using a set of in vivo and in vitro studies, we show that an autocrine FGF10?FGFR2b signaling loop is established in the mutant lung mesenchyme, which has several consequences. It prevents the entry of the smooth muscle progenitors into the smooth muscle cell (SMC) lineage and results in reduced fibronectin and elastin deposition. Levels of...

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... reconnaissance. Presently the signal ompWa captain rushed up, salutec snappily, anI reported. When the general inquired how. ...

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... of the AR (25). Dihydrotestosterone increases Wnt signaling activity in preosteoblasts. Functional interactions between ...

UK PubMed Central (United Kingdom)

The importance of cancer metabolism has been appreciated for many years, but the intricacies of how metabolic pathways interconnect with oncogenic signaling are not fully understood. With a clear understanding...Full Text Available

Science.gov (United States)

Digital audio sampling is explained, and some of its implications in digital sound applications are discussed. Digital sound equipment is rapidly replacing analog recording devices as the state-of-the-art in audio technology. The philosophy of digital recording involves doing away with the continuously variable analog waveforms and turning the patterns into numbers. A digital recording device rapidly samples the incoming sounds, quantifying the signal into a series of numerical values (binary codes). Although digital sound eliminates many of the traditional analog problems, digital signal processing presents key problems in sampling rates and synchronization. Careful control is necessary to check signals through each step in the audio chain. The advantages of digital audio processing include increased signal-to-noise ratio, no flutter, transparent generation of copies, and sound manipulation. These ...

UK PubMed Central (United Kingdom)

Chimpanzee (Pan troglodytes) agonistic screams are graded vocal signals that are produced in a context-specific manner. Screams given by aggressors and victims can be discriminated...Full Text Available

UK PubMed Central (United Kingdom)

CAAX proteins are widely involved in global cellular functions such as proliferation, differentiation, and carcinogenesis. As an important modulator of biological activity, signal transduction via protein...Full Text Available

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... Introduction to the Signal Regiment Cisco Academy 1-4 (CCNA) Engineering Math Basic Electronics/Digital Logic (replaced C Programming ...

Science.gov (United States)

Readout integrated circuits (ROICs) for focal plane arrays (FPAs) have become increasingly complex to meet the needs of modern infrared systems. BAE Systems has pioneered a number of advanced signal processing architectures for FPA ROICs. Demonstrated signal processing capabilities of BAE Systems FPAs include analog-to-digital conversion, offset subtraction, individual pixel automatic gain compensation, transient noise suppression, on-FPA defect deselection, reconfigurable pixels, spatial neural network processing and subframe noise averaging. BAE Systems FPA advanced signal processing is not just for demonstrations, but is used in many of their deliverable FPAs, improving real system performance.

Energy Technology Data Exchange (ETDEWEB)

The problem of passively tracking a moving signal source has importance in a variety of applications such as radar, sonar, seismology, and radio astronomy. In many applications, only limited information is available about the signal source. It will be assumed here that only the signals which are detected by the sensors and the velocity of the source signal are known. The objective of this document is to present a program which passively tracks a target using an array of sensors. This program is available in MATLAB, version 3.5. The algorithm which is implemented consists of three main parts: time delay estimation, passive localization, and data post processing. Each of these parts are discussed, and the mathematical foundation for their solution given. Following, this the organization of the program is presented, and an example of its usage is given.

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To assess whether ring enhancements of liver metastases on Mn-DPDP enhanced, early MR images were well visualized on delayed images, as compared with those of hepatocellular carcinomas (HCC), and to investigate the detection accuracy and conspicuity of each tumor. Twenty patients with liver metastases and 15 with HCC were studied by Mn-DPDP enhanced, T1-weighted MR images. Peripheral ring enhancement and conspicuity were investigated. Differences in detection accuracy and frequency of ring enhancement in liver metastases and HCC were assessed. In liver metastases (n= 69), 44 cases (63.8%) without ring enhancement and 25 (36.2%) with were noted on early images. Sixteen cases (23.2%) without ring enhancement, 38 (55.1%) with ring enhancement similar to the early images, and 15 (21.7%) with prominent ring ...

UK PubMed Central (United Kingdom)

We tested the hypothesis that the basal release of nitric oxide (NO) from endothelial cells modulates contractile activity in the corpus cavernosum (CC) via inhibition of the RhoA/Rho-kinase signaling...Full Text Available

International Nuclear Information System (INIS)

An eddy current inspection has been applied for a pre-service and in-service examination of a steam generator in nuclear power plants. The experience from the inspection of steam generators showed that many plants had an excessive number of tubes with eddy current noise signals over several hundreds, which originated from manufacturing anomalies. The plants in U.S suffered significant downstream inspection costs, history reviews, and diagnostic testing because some signals resembled flaws and others masked a flaw. These lessens learned resulted in issuing the guidelines for steam generator tubing specifications and repair, in order to reduce the number of anomalous signals in the tubes and also to provide the requirement of a signal to noise ratio by applying a field type examination with bobbin coil eddy current probes at a manufacturing process. Besides the noise signals of a ...

UK PubMed Central (United Kingdom)

The Epstein-Barr virus protein, LMP1, is a functional mimic of the cellular receptor CD40, but signals to B lymphocytes in an amplified and sustained manner compared to CD40. LMP1 contributes...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

A micro-computer based fuzzy logic power system stabilizer is applied to a micro-machine system to investigate its efficiency in real time control. The stabilizing signal is determined by using measured speed or real power signals at every sampling time to damp the system oscillations. The results show the proposed stabilizer improves the system damping effectively subject to various types of disturbances.

International Nuclear Information System (INIS)

Object: To prevent a sudden drop in the level of a coolant in a annular pipe encased within a downcomer pipe. Structure: The coolant levels in annular pipes encased within downcomer pipes are simultaneously measured by level gauges which generate signals representative of coolant levels. The signals are fed to a level control system which will actuate valves to regulate the cover gas pressure in order to average the level differences among the annular pipes in different downcomer pipes. (Kamimura, M.).

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Luminescence stimulated from feldspars using wavelengths in the infrared region can be applied to the dating of sedimentary grains. Reported stimulation spectra are very similar for a wide range of feldspars, but their emission spectra show greater variation. For accurate dating it is critical that unstable infrared-stimulated luminescence (IRSL) signals are removed from the laboratory-irradiated grains. Several approaches to isolate a thermally stable signal are described. (author).

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A gas-diesel dual fuel engine apparatus is described having a diesel engine, a diesel fuel supply system including a diesel fuel injection pump, a gaseous fuel supply system including a gaseous fuel regulating valve, and a governing and controlling device for governing the speed of the engine through the control of fuel supplied to the engine and controlling the switchover of the operation of the engine between a diesel fuel mode and a gaseous fuel mode. The improvement of the governing and controlling device consists of: (a) at least one electronic governor means adapted to compare a speed signal representing the actual operating speed of the diesel engine with a set speed signal representing the set speed thereof; (b) a pair of electric actuator means having respective power amplifier circuits and mechanically connected to the diesel fuel injection pump and the gaseous fuel regulating valve, respectively, for the actuation thereof; (c) mode ...

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Stabilization of the particle beam position with respect to the focusing optics in the third generation synchrotron light sources is crucial to achieving low emittance and high brightness. For this purpose, global and local beam orbit correction feedbacks will be implemented in the APS storage ring. In this article, the authors discuss application of digital signal processing to particle/photon beam position feedback using the PID (proportional, integral, and derivative) control algorithm.

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This book contains nomographs for analysis and design of signalized intersections and thoroughly explains how to use them. The nomographs simplify and reduce the work that otherwise would have to be done by hand. The nomograph method for computing capacity has a significant advantage over computerized methods: it provides insight into the interaction between the various factors in the solution process for design analysis.

International Nuclear Information System (INIS)

Accurate modeling of the enhanced diffusion of boron during rapid thermal annealing has been accomplished by incorporating the effects of extended defect formation and annealing on enhanced diffusion into a multizone, semiempirical model. The multizone model divides the implant profile into three zones defining regions of different defects and diffusion enhancements. The model also contains the initial enhanced diffusion and the transient diffusion effects associated with the dissolution of defect clusters and the annealing of extended defects, respectively. The saturation time for transient-enhanced diffusion contains an exponential function of implant dose in order to model the increase in point defect generated with higher implant dose. As a result, the model accurately simulates the boron diffusion profile over a wide range of implant doses and also shows the immobile boron peak ...

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In this two chapter report, instrumentation used to collect seismic data is described. This data acquisition system has two parts: (1) portable anolog seismic recorders and related ``hand-held-testers`` (HHT) and (2) portable digitizing units. During the anolog recording process, ground motion is sensed by a 2-Hz vertical-component seismometer. The voltage output from the seismometer is split without amplification and sent to three parallel amplifier circuit boards. Each circuit board amplifiers the seismic signal in three stages and then frequency modulates the signal. Amplification at the last two stages can be set by the user. An internal precision clock signal is also frequency modulated. The three data carrier frequencies, the clock carrier frequency, and a tape-speed compensation carrier frequency are summed and recorded on a recorded on a cassette tape. During the digitizing process, the cassette tapes are played ...

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An ignition timing control apparatus is described for an internal combustion engine having a reference ignition timing comprising: sensing means for sensing vibrations including knocks of the engine; knock signal deriving means for deriving knock signals from the output of the sensing means; correction magnitude determining means for determining from the knock signals derived by the knock signal deriving means of ignition timing correction magnitude for suppressing the occurrence of knock; displacement magnitude determining means for determining from at least one of an output of the knock signal deriving means and an output of the correction magnitude determining means as a displacement magnitude for the reference ignition timing corresponding to the octane rating of a fuel used in the engine; and ignition timing determining means for setting the reference ignition timing at an ...

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We measured ESR of phosphorous-doped silicon with a low concentration of P, n, at high magnetic fields and low temperatures to investigate the states of nuclear spin. A sample with n = 6.52 x 10{sup 16} /cm{sup 3} was studied at 2.85 T (80 GHz) from 30 K to 2.3 K by field-modulating cw-ESR for a fixed 0 dB power. As the temperature was lowered, the out-of-phase signal appeared around 18 K, reached at a maximum intensity at 13 K, and disappeared around 6 K. The out-of-phase signal is referred to the field modulation. The in-phase signal started to change from the derivative of absorption spectrum at high temperatures to absorption-like shape around 15 K and asymmetry of intensity for two peaks of hyperfine-separated signals increased as temperatures was lowered. Below 10 K, the saturation of the in-phase signal started to appear. We speculate that the asymmetry is caused by ...

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Past movement on faults can be dated by measurement of the intensity of ESR signals in quartz. These signals are reset by local lattice deformation and local frictional heating on grain contacts at the time of fault movement. The ESR signals then grow back as a result of bombardment by ionizing radiation from surrounding rocks. The age is obtained from the ratio of the equivalent dose, needed to produce the observed signal, to the dose rate. Fine grains are more completely reset during faulting, and a plot of age vs. grain size shows a plateau for grains below critical size; these grains are presumed to have been completely zeroed by the last fault activity. We carried out ESR dating of fault rocks collected near the Gori nuclear reactor. Most of the ESR signals of fault rocks collected from the basement are saturated. This indicates that the last movement of the faults had occurred ...

Science.gov (United States)

Varying load can cause changes in a measured gearbox vibration signal. However, conventional techniques for fault diagnosis are based on the assumption that changes in vibration signal are only caused by deterioration of the gearbox. There is a need to develop a technique to provide accurate state indicator of gearbox under fluctuating load conditions. This paper presents an approach to gear fault diagnosis based on complex Morlet continuous wavelet transform under this condition. Gear motion residual signal, which represents the departure of time synchronously averaged signal from the average tooth-meshing vibration, is analyzed as source data due to its lower sensitiveness to the alternating load condition. A fault growth parameter based on the amplitude of wavelet transform is proposed to evaluate gear fault advancement quantitatively. We found that this parameter is insensitive to varying load and ...

UK PubMed Central (United Kingdom)

A critical research priority for our field is to develop treatments that enhance cognitive functioning in schizophrenia and thereby attenuate the functional losses associated with the illness. In this...Full Text Available

UK PubMed Central (United Kingdom)

Resonance Raman spectra are reported for the organometallic phenyl-FeIII complexes of horse heart myoglobin. We observed the resonance enhancement of the ring vibrational modes of the bound phenyl group....Full Text Available

UK PubMed Central (United Kingdom)

How transcription factors interpret the cis-regulatory logic encoded within enhancers to mediate quantitative changes in spatiotemporally restricted expression patterns during animal...Full Text Available

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The overall objective of this project was to use molecular genetics to develop strains of bacteria with enhanced ability to remove sulfur from coal, and to obtain data that will allow the performance and economics of a coal biodesulfurization process to be predicted. (VC)

UK PubMed Central (United Kingdom)

SummaryConvection-enhanced delivery (CED) of substances within the human brain is becoming a more frequent experimental treatment option in the management of brain tumors, and...Full Text Available

UK PubMed Central (United Kingdom)

Background:There is a need for simple imaging parameters capable of predicting therapeutic outcome.Methods:This retrospective study analysed 50 patients...Full Text Available

UK PubMed Central (United Kingdom)

Convection-enhanced drug delivery (CED) is a novel approach to delivering drugs into brain tissue. Drugs are delivered continuously via a catheter, enabling large volume distributions of high drug concentrations...Full Text Available

Science.gov (United States)

... Tunable semiconductor lasers are essential components for links employing optical frequency modulation (OFM) for enhanced dynamic range or ...

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High-resolution spectroscopy of 13 bright red giants and Ba stars shows selective enhancement of Ba in three of them, HD 65699 (Ba 2), ..cap alpha..TrA (K4 III), and epsilonPeg (K2 Ib). Infrared spectra available for HD 65699 show that Sr is enhanced, too. This selective enhancement is discussed in terms of a modified s-process which converts some of the pre-existing r- and s-process matter into the magic nuclei /sup 88/Sr and /sup 138/Ba.

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No abstract prepared.

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... Descriptors : *AMMUNITION, *CONTAINERS, *CARTRIDGES, *COMBUSTIBLE CARTRIDGE CASES, *CARTRIDGE CASES, *ANTITANK ...

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Science.gov (United States)

Recently, Wang et al. proposed a three-party simultaneous quantum secure direct communication (3P-SQSDC) scheme with EPR pairs, which enables three involved parties to exchange their secret messages simultaneously by using an EPR pair. This work proposed an enhancement on Wang et al.'s scheme. With the enhancement, the communications in the improved 3P-SQSDC can be paralleled and thus improves the protocol efficiency.

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Transient enhanced diffusion in boron-implanted silicon is interpreted as being due to the fact that during rapid thermal annealing a relaxation process takes place, associated with quasi-chemical reactions including defects. A simple analytical model makes it possible to describe the annealing mechanism on a microscopic scale in terms of reaction-diffusion processes. The measured dependences of the boron diffusion coefficient of the enhanced diffusion on time, temperature and implantation energy are satisfactorily explained. (author).

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A passive heat exchange enhancement structure which operates by free convection includes a flat mounting portion having a plurality of integral fins bent outwardly from one side edge thereof. The mounting portion is securable around a stovepipe, to a flat surface or the like for transferring heat from the pipe through the fins to the surrounding air by rotation-enhanced free convection.

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Lipiodol Ultra-Fluid (Lipiodol) is widely applied in the transcatheter arterial embolization (TAE). We studied signal intensity, the T1 relaxation time and the T2 relaxation time of Lipiodol itself using Siemens Magnetom H15-2 T (1.5 Tesla) and Magnetom M10 (1.0 Tesla). Lipiodol showed higher signal intensity than saline solution on the T1-weighted images (short TR, short TE technique in spin echo method). On the T2-weighted images (long TR, long TE technique in spin echo method), Lipiodol showed lower signal intensity than saline solution. The T1 relaxation time of Lipiodol, measured at 1.0 T, was 201 msec and 218 msec at 1.5 T. The T2 relaxation time of Lipiodol, measured at 1.0 T, was 127 msec; and 167 msec at 1.5 T. The signal intensity of Lipiodol at 1.0 T was higher than the intensity at 1.5 T. Shorter T1 relaxation time of Lipiodol at 1.0 T is probably responsible for the higher intensity at 1.0 ...

Energy Technology Data Exchange (ETDEWEB)

In order to evaluate dynamic behavior of underground cracks, analysis and detection were attempted on multiple acoustic emission (AE) events. The multiple AE is a phenomenon in which multiple AE signals generated by underground cracks developed in an extremely short time interval are superimposed, and observed as one AE event. The multiple AE signal consists of two AE signals, whereas the second P-wave is supposed to have been inputted before the first S-wave is inputted. The first P-wave is inputted first, where linear three-dimensional particle movements are observed, but the movements are made random due to scattering and sensor characteristics. When the second P-wave is inputted, the linear particle movements are observed again, but are superimposed with the existing input signals and become multiple AE, which creates poor S/N ratio. The multiple AE detection determines it a multiple AE event when ...