WorldWideScience
1

Yeast as a Model System to Study Tau Biology  

Science.gov (United States)

Hyperphosphorylated and aggregated human protein tau constitutes a hallmark of a multitude of neurodegenerative diseases called tauopathies, exemplified by Alzheimer's disease. In spite of an enormous amount of research performed on tau biology, several crucial questions concerning the mechanisms of tau toxicity remain unanswered. In this paper we will highlight some of the processes involved in tau biology and pathology, focusing on tau phosphorylation and the interplay with oxidative stress. In addition, we will introduce the development of a human tau-expressing yeast model, and discuss some crucial results obtained in this model, highlighting its potential in the elucidation of cellular processes leading to tau toxicity.

2011-04-06

2

Loss of ?-III spectrin leads to Purkinje cell dysfunction recapitulating the behaviour and neuropathology of SCA5 in humans  

UK PubMed Central (United Kingdom)

Mutations in SPTBN2, the gene encoding β-III spectrin, cause spinocerebellar ataxia type 5 in humans (SCA5), a neurodegenerative disorder resulting in loss of motor...Full Text Available

2010-04-07

3

Glutamate Transporter EAAT2 Expression is Up-Regulated in Reactive Astrocytes in Human Periventricular Leukomalacia  

UK PubMed Central (United Kingdom)

The major neuropathological correlate of cerebral palsy in premature infants is periventricular leukomalacia (PVL), a disorder of the immature cerebral white matter. Cerebral ischemia leading...Full Text Available

2008-05-10

4

Non local theories: New rules for old diagrams  

International Nuclear Information System (INIS)

We show that a general variant of the Wick theorems can be used to reduce the time ordered products in the Gell-Mann and Low formula for a certain class on non local quantum field theories, including the case where the interaction Lagrangian is defined in terms of twisted products. The only necessary modification is the replacement of the Stueckelberg-Feynman propagator by the general propagator (the 'contractor' of Denk and Schweda) D(y-y';#tau#-#tau#')=(1)/i(#DELTA#_+(y-y')#theta#(#tau#-#tau#')+#DELTA#+(y'-y)#theta#(#tau#'-#tau#)), where the violations of locality and causality are represented by the dependence of #tau#,#tau#' on other points, besides those involved in the contraction. This leads naturally to a diagrammatic expansion of the Gell-Mann and Low formula, in terms of the same diagrams as in the local case, the only necessary modification concerning the Feynman rules. The ordinary local ...

2004-08-01

5

Common Origin of mu-tau and CP Breaking in Neutrino Seesaw, Baryon Asymmetry, and Hidden Flavor Symmetry  

CERN Document Server

We conjecture that all CP violations (both Dirac and Majorana types) arise from a common origin in neutrino seesaw. With this conceptually attractive and simple conjecture, we deduce that mu-tau breaking shares the common origin with all CP violations. We study the common origin of mu-tau and CP breaking in the Dirac mass matrix of seesaw Lagrangian (with right-handed neutrinos being mu-tau blind), which uniquely leads to inverted mass-ordering of light neutrinos. We then predict different correlations between the two small mu-tau breaking observables theta_{13} - 0 and theta_{23} -45, which can be tested against our previous normal mass-ordering scheme by the on-going oscillation experiments. We also analyze the correlations of theta_{13} with Jarlskog invariant and neutrinoless double-beta-decay observable. From the common origin of CP and mu-tau breaking in ...

2011-01-01

6

'Mu-Tau' symmetry, tribimaximal mixing and four zero neutrino Yukawa textures  

CERN Document Server

Within the type-I seesaw framework with three heavy right chiral neutrinos and in the basis where the latter and the charged leptons are mass diagonal, a near `mu-tau' symmetry in the neutrino sector is strongly suggested by the neutrino oscillation data. There is further evidence for a close to the tribimaximal mixing pattern which subsumes `mu-tau' symmetry. On the other hand, the assumption of a (maximally allowed) four zero texture in the Yukawa coupling matrix Y_nu in the same basis leads to a highly constrained and predictive theoretical scheme. We show that the requirement of an exact `mu-tau' symmetry, coupled with observational constraints, reduces the `seventy two' allowed textures in such a `Y_nu' to 'only four' corresponding to just two different forms of the light neutrino mass matrix `m_nu'. The effect of each of these on measurable quantities can be described, apart from an overall factor ...

2009-01-01

7

Measurement of inelastic charmonium production at HERA  

Energy Technology Data Exchange (ETDEWEB)

This thesis presents measurements of inelastic photoproduction and electroproduction of J/{psi} mesons in ep scattering at HERA. The data was collected by the H1 detector during the HERA II running and corresponds to an integrated luminosity of L {approx} 166 pb{sup -1} in the photoproduction analysis and L {approx} 315 pb{sup -1} in the electroproduction analysis. In both analyses the elasticity of the J/{psi} meson is restricted to a medium range of 0.3 {<=} z {<=} 0.9. The kinematic range of the photoproduction analysis is defined by Q{sup 2} {approx} 0 GeV{sup 2}, 60 {<=}W{sub {gamma}}{sub p}{<=} 240 GeV and P{sub {tau}}{sub ,{psi}}{>=} 1 GeV{sup 2}, whereas the electroproduction analysis is restricted to 3.6 {<=} Q{sup 2} {<=} 100 GeV{sup 2}, 50 {<=}W{sub {gamma}}{sub p}{<=} 225 GeV, and P{sup *}{sub {tau}}{sub ,} {sub {psi}} {>=} 1 GeV. Here P{sup *}{sub ...

2008-09-15

8

Improved measurement of $\\psi (2S)$ decays into $\\tau ^{+}\\tau ^{-}$  

CERN Document Server

Using 14M $\\psi (2S)$ events collected at BESII, the branching fraction of $\\psi (2S)\\to \\tau ^{+}\\tau ^{-}$ is measured to be $Br_{\\tau \\tau}=(3.10\\pm 0.21\\pm 0.38)\\times 10^{-3}$, where the first error is statistical and the second is systematic.

2006-01-01

9

Cortical neuritic plaques and hippocampal neurofibrillary tangles are related to dementia severity in elderly schizophrenia patients  

British Library Electronic Table of Contents (United Kingdom)

Cognitive decline has been described in elderly patients with schizophrenia, but the underlying pathology remains unknown. Some studies report increases in plaques and neurofibrillary tangles, but there is no evidence for an increased risk for Alzheimer's disease (AD) in elderly schizophrenics. Models of a decreased cerebral reserve suggest that increases in AD-related neuropathology below the threshold for a neuropathological diagnosis could be related to dementia severity in elderly schizophrenia patients. We tested this hypothesis in 110 autopsy specimens of schizophrenia patients, without a neuropathological diagnosis of AD or other neurodegenerative disorders. Furthermore, we assessed the effects of apolipoprotein E (ApoE) status, a known genetic risk factor for AD. Measures of densit...

2010-01-01

10

Discrete simulation of power law noise  

CERN Document Server

A method for simulating power law noise in clocks and oscillators is presented based on modification of the spectrum of white phase noise, then Fourier transforming to the time domain. Symmetric real matrices are introduced whose traces--the sums of their eigenvalues--are equal to the Allan variances, in overlapping or non-overlapping forms, as well as for the corresponding forms of the modified Allan variance. Diagonalization of these matrices leads to expressions for the probability distributions for observing a variance at an arbitrary value of the sampling or averaging interval $\\tau$, and hence for estimating confidence in the measurements. A number of applications are presented for the common power-law noises.

2011-01-01

11

Subacute neuropathological effects of microplanar beams of x-rays from a synchrotron wiggler.  

UK PubMed Central (United Kingdom)

Microplanar beam radiation therapy has been proposed to treat brain tumors by using a series of rapid exposures to an array of parallel x-ray beams, each beam having uniform microscopic thickness and...Full Text Available

1995-09-12

12

Novel Analogs and Stereoisomers of the Marine Toxin Neodysiherbaine with Specificity for Kainate Receptors  

UK PubMed Central (United Kingdom)

Antagonists for kainate receptors (KARs), a family of glutamate-gated ion channels, are efficacious in a number of animal models of neuropathologies, including epilepsy, migraine pain, and anxiety....Full Text Available

2008-02-01

13

Imaging Alzheimer Pathology in Late-Life Depression With PET and Pittsburgh Compound-B  

UK PubMed Central (United Kingdom)

There is increasing evidence for an empiric link between late-life depression and Alzheimer disease (AD). The neuropathology of AD, previously only confirmed at autopsy, may now be detectable...Full Text Available

2008-01-01

14

Encephalitis lethargica and the influenza virus. III. The influenza pandemic of 1918/19 and encephalitis lethargica: neuropathology and discussion*  

UK PubMed Central (United Kingdom)

This is the second of two papers which critically examine the relationship between the 1918/19 influenza pandemic and encephalitis lethargica (EL). The role of influenza in the etiology of EL...Full Text Available

2009-10-01

15

Design and R&D for the forward calorimeter and silicon tracker of the $\\tau$cF detector  

CERN Document Server

Design and R&D for the forward calorimeter and silicon tracker of the $\\tau$cF detector

1993-01-01

16

B#->##tau#"+#tau#"-(X) decays: First constraints and phenomenological implications  

International Nuclear Information System (INIS)

The study of B#->##tau#"+#tau#"-(X) decays can provide us with a better understanding of the third generation, and can be a useful probe of physics beyond the standard model. We present a model-independent analysis of these decays. We classify new physics that can largely enhance the decay rates and we discuss the constraints implied by other processes. Experimentally, flavor-changing neutral current B decays into final state #tau# close-quote s are still unconstrained. Searches for B decays with large missing energy at CERN LEP provide the first limits. We estimate that existing data already imply bounds on the B_d#->##tau#"+#tau#"-, B_s#->##tau#"+#tau#"-, and B#->#X#tau#"+#tau#"- decay rates at the few percent level. Although these bounds are over four orders of magnitude above the standard model predictions, they provide the first constraints on some leptoquarks, and ...

18

Higgs-Mediated $B_{s,d}^0 \\to \\mu\\tau, e\\tau$ and $\\tau \\to 3\\mu, e\\mu\\mu$ Decays in Supersymmetric Seesaw Models  

CERN Document Server

We study the rates allowed for the Higgs-mediated decays $B_{s,d}^0\\to\\mu\\tau, e\\tau$ and $\\tau\\to \\mu\\mu\\mu, e\\mu\\mu$ in supersymmetric seesaw models, assuming that the only source of lepton flavour violation (LFV) is the renormalization of soft supersymmetry-breaking terms due to off-diagonal singlet-neutrino Yukawa interactions. These decays are strongly correlated with, and constrained by, the branching ratios for $B_{s,d}^0\\to\\mu\\mu$ and $\\tau\\to \\mu(e)\\gamma.$ Parametrizing the singlet-neutrino Yukawa couplings $Y_\

2002-01-01

19

Duality and dilation  

Energy Technology Data Exchange (ETDEWEB)

This paper reviews and elaborates on the issue of the dilaton transformation under the usual {tau} {yields} {alpha}{prime}/{tau} target space duality and its non-static generalization (or {sigma}-model duality). It is found that the transformation law {tau} {yields} {alpha}{prime}/{tau}, {phi} {yields} {phi} In ({tau}/{alpha}{prime}) which guarantees duality at the one-loop {sigma}-model level should be modified at two (and higher) loop order. The non-static duality is illustrated on the example of cosmological solutions in D {ge} 2 with time-dependent radii of space torus.

1991-06-21

20

Inhibition of tau fibrillization by oleocanthal via reaction with the amino groups of tau  

Science.gov (United States)

Tau is a microtubule-associated protein that promotes microtubule assembly and stability. In Alzheimer's disease and related tauopathies, tau fibrillizes and aggregates into neurofibrillary tangles. Recently, oleocanthal isolated from extra virgin olive oil was found to display non-steroidal anti-inflammatory activity similar to ibuprofen. Since our unpublished data indicates an inhibitory effect of oleocanthal on A? fibrillization, we reasoned that it might inhibit tau fibrillization as well. Herein we demonstrate that oleocanthal abrogates fibrillization of tau by locking tau into the naturally unfolded state. Using PHF6 consisting of the amino acid residues VQIVYK, a hexapeptide within the third repeat of tau that is essential for fibrillization, we show that oleocanthal forms an adduct with the lysine via initial Schiff base formation. Structure and function ...

2009-06-15

21

Search for Tau-Lepton Decays to Seven Or More Pions With BaBar  

Energy Technology Data Exchange (ETDEWEB)

We report the results of searches for several decay modes of the {tau}-lepton with {ge} 7 pions in the final state using 207 x 10{sup 6} {tau}-pairs collected with the BaBar detector. For the decays with 7 charged pions in the final state we find the following 90% CL upper limits: B({tau}{sup -} {yields} 4{pi}{sup -}3{pi}{sup +}({pi}{sup 0}){nu}{sub {tau}}) < 3.0 x 10{sup -7}, B({tau}{sup -} {yields} 4{pi}{sup -}3{pi}{sup +}{nu}{sub {tau}}) < 4.3 x 10{sup -7} and B({tau}{sup -} {yields}) B({tau}{sup -} {yields} 4{pi}{sup -}3{pi}{sup +}{pi}{sup 0}{nu}{sub {tau}}) < 2.5 x 10{sup -7}. We also search for the decay {tau}{sup -} {yields} 3{pi}{sup -}2{pi}{sup +}2{pi}{sup 0}{nu}{sub {tau}} and report a 90% CL upper limit of < 3.4 x 10{sup ...

2007-11-02

22

lib_general.pro - ECCO2  

Science.gov (United States)

Returns singular values (sigma), ;left field (x) vectors, ..... n) do begin point=ngbrs(i) if (point+tau le nt-1) then begin if (x(point+tau,0) ne q) then .... ;FILTER ;applies a gaussian filter in the frequency domain function filter, x ...

23

Selective Interaction of Lansoprazole and Astemizole with Tau Polymers: Potential New Clinical Use in Diagnosis of Alzheimer's Disease  

UK PubMed Central (United Kingdom)

We describe the interactions of two benzimidazole derivatives, astemizole (AST) and lansoprazole (LNS), with anomalous aggregates of tau protein (neurofibrillary tangles). Interestingly, these...Full Text Available

2010-01-01

24

CP Violation in Top Physics at the NLC  

CERN Document Server

Top quark is extremely sensitive to non-standard CP violating phases. General strategies for exposing different types of phases at the NLC are outlined. SUSY phase(s) cause PRA in $t\\to Wb$. The transverse polarization of the $\\tau$ in the reaction $t\\to b\\tau\

1996-01-01

25

Unsteady aerodynamic forces of a flapping wing.  

Science.gov (United States)

The unsteady aerodynamic forces of a model fruit fly wing in flapping motion were investigated by numerically solving the Navier-Stokes equations. The flapping motion consisted of translation and rotation [the translation velocity (u(t)) varied according to the simple harmonic function (SHF), and the rotation was confined to a short period around stroke reversal]. First, it was shown that for a wing of given geometry with u(t) varying as the SHF, the aerodynamic force coefficients depended only on five non-dimensional parameters, i.e. Reynolds number (Re), stroke amplitude (Phi), mid-stroke angle of attack (alpha(m)), non-dimensional duration of wing rotation (Delta tau(r)) and rotation timing [the mean translation velocity at radius of the second moment of wing area (U), the mean chord length (c) and c/U were used as reference velocity, length and time, respectively]. Next, the force coefficients were investigated for a case in which typical values of these ...

2004-03-01

26

Modulation of proton NMR free induction decay by spin diffusion  

Energy Technology Data Exchange (ETDEWEB)

The effects of spin diffusion on the free induction decay (FID) of protons associated with the noncrystalline domains of two polymers, polyethylene and blended Nylon 66 (ZYTEL-408), have been examined using Goldman--Shen NMR pulse sequence ((1/2)..pi..x-t/sub 0/-(1/2)..pi..x-bar-tau-(1/2)..pi..x-t). At tau< or approx. =100 ..mu..s, the FID is drastically distorted from the exponential form while at longer tau(tau> or approx. =500 ..mu..s) an exponential FID is observed; but its transverse spin relaxation rate is smaller than that of the FID obtained after a single (1/2)..pi..x pulse and approaches this value at the limit of large tau. These findings are interpreted in terms of the theory of rapid spin diffusion. The spatial variation in the spin relaxation rate within the noncrystalline domain is inferred.

1982-02-01

27

The Galactic Center Region Gamma Ray Excess from A Supersymmetric Leptophilic Higgs Model  

CERN Document Server

In a recent paper by Hooper and Goodenough, data from the Fermi Gamma Ray Telescope was analyzed and an excess of gamma rays was found in the emission spectrum from the Galactic Center Region. Hooper and Goodenough show that the excess can be well explained by 7-10 GeV annihilating dark matter with a power law density profile if the dark matter annihilates predominantly to tau pairs. In this paper we present such a dark matter model by extending the MSSM to include four Higgs doublets and one scalar singlet. A Z2 symmetry is imposed that enforces a Yukawa structure so that the up quarks, down quarks, and leptons each receive mass from a distinct doublet. This leads to an enhanced coupling of scalars to leptons and allows the model to naturally achieve the required phenomenology in order to explain the gamma ray excess. Our model yields the correct dark matter thermal relic density and avoids collider bounds from measurements of the Z width as ...

2011-01-01

28

Phenomenological analysis of heavy hadron lifetimes  

International Nuclear Information System (INIS)

A phenomenological analysis of lifetimes of bottom and charmed hadrons within the framework of the heavy quark expansion is performed. The baryon matrix element is evaluated using the bag model and the nonrelativistic quark model. We find that bottom-baryon lifetimes follow the pattern #tau#(#OMEGA#_b)#approx =##tau#(#XI#_b"-)>#tau#(#LAMBDA#_b)#approx =##tau#(#XI#_b"0). However, neither the lifetime ratio #tau#(#LAMBDA#_b)/#tau#(B_d) nor the absolute decay rates of the #LAMBDA#_b baryon and B mesons can be explained. One way of solving both difficulties is to allow the presence of linear 1/m_Q corrections by scaling the inclusive nonleptonic width with the fifth power of the hadron mass m_H__Q rather than the heavy quark mass m_Q. The hierarchy of bottom baryon lifetimes is dramatically modified to ...

29

Instanton contributions to the $\\tau$ decay widths  

CERN Document Server

Contrary to some previous claims, we find a sizable instanton contribution to the finite energy sum rule used to extract the value of the strong coupling from the measured $\\tau$ decay widths. It is of the same order of magnitude as standard nonperturbative corrections induced by vacuum quark and gluon condensates. Our result indicates that there might be no hierarchy of power corrections in finite energy sum rules at the scale of $\\tau$ mass. Therefore, the standard nonperturbative corrections do not necessarily improve the accuracy of the theoretical predicition, but can rather be used to estimate an intrinsic accuracy of the pure perturbative calculation, which turns out to be rather high on this evidence, of order one percent.

1993-01-01

30

The ternary system cerium-palladium-silicon  

International Nuclear Information System (INIS)

Phase relations in the ternary system Ce-Pd-Si have been established for the isothermal section at 800 deg. C based on X-ray powder diffraction and EMPA techniques on about 130 alloys, which were prepared by arc-melting under argon or powder reaction sintering. Eighteen ternary compounds have been observed to participate in the phase equilibria at 800 deg. C. Atom order was determined by direct methods from X-ray single-crystal counter data for the crystal structures of #tau#_8-Ce_3Pd_4Si_4 (U_3Ni_4Si_4-type, Immm; a=0.41618(1), b=0.42640(1), c=2.45744(7) nm), #tau#_1_6-Ce_2Pd_1_4Si (own structure type, P4/nmm; a=0.88832(2), c=0.69600(2) nm) and also for #tau#_1_8-CePd_1_-_xSi_x (x=0.07; FeB-type, Pnma; a=0.74422(5), b=0.45548(3), c=0.58569(4) nm). Rietveld refinements established the atom arrangement in the structures of #tau#_5-Ce_3PdSi_3 (Ba_3Al_2Ge_2-type, Immm; a=0.41207(1), b=0.43026(1), ...

2009-09-01

31

b-$\\tau$ Unification and neutrino masses in SU(5) extensions of the MSSM with radiative electroweak symmetry breaking  

CERN Document Server

We make a complete analysis of the Yukawa coupling unification in SU(5) extensions of the MSSM in the framework of the radiative symmetry breaking scenario. Both logarithmic and finite threshold corrections of sparticles have been included in the determination of the gauge and Yukawa couplings at M_Z. The effect of the heavy masses of each model in the renormalization group equations is also included. We find that in the minimal SU(5) model b-tau Yukawa unification can be achieved for too large a value of alpha_s. On the other hand the Peccei-Quinn version of the Missing Doublet model, with the effect of the right handed neutrino also included, exhibits b-tau unification in excellent agreement with all low energy experimental data. Unification of all Yukawa couplings is also discussed.

1997-01-01

32

Unraveling duality violations in hadronic tau decays  

Energy Technology Data Exchange (ETDEWEB)

There are some indications from recent determinations of the strong coupling constant alpha_s and the gluon condensate that the Operator Product Expansion may not be accurate enough to describe non-perturbative effects in hadronic tau decays. This breakdown of the Operator Product Expansion is usually referred to as being due to"Duality Violations." With the help of a physically motivated model, we investigate these duality violations. Based on this model, we argue how they may introduce a non-negligible systematic error in the current analysis, which employs finite-energy sum rules with pinched weights. In particular, this systematic effect might affect the precision determination of alpha_s from tau decays. With a view to a possible future application to real data, we present an alternative method for determining the OPE coefficients that might help estimating, and possibly even reducing, this systematic error.

2008-03-03

33

Tau inhibits tubulin oligomerization induced by prion protein  

British Library Electronic Table of Contents (United Kingdom)

In previous studies we have demonstrated that prion protein (PrP) interacts with tubulin and disrupts microtubular cytoskeleton by inducing tubulin oligomerization. These observations may explain the molecular mechanism of toxicity of cytoplasmic PrP in transmissible spongiform encephalopathies (TSEs). Here, we check whether microtubule associated proteins (MAPs) that regulate microtubule stability, influence the PrP-induced oligomerization of tubulin. We show that tubulin preparations depleted of MAPs are more prone to oligomerization by PrP than those containing traces of MAPs. Tau protein, a major neuronal member of the MAPs family, reduces the effect of PrP. Importantly, phosphorylation of Tau abolishes its ability to affect the PrP-induced oligomerization of tubulin. We propose that t...

2011-01-01

34

Statistical estimation of the lifetimes of charmed particles  

Energy Technology Data Exchange (ETDEWEB)

Various statistical methods for the estimation of the mean lifetimes of charmed particles have been considered. It is shown that the usual estimates of the maximum likelihood in some cases do not exist or may have rather great positive bias, if the statistics are low. Alternative estimates of the mean lifetime tau are discussed. Among them the 'jackknife' estimate of tau is considered. The minimum variance unbiased estimates of the average rate of decay 1/tau have been derived for some particular cases. It is also shown that the usual estimate of the ratio of the mean lifetimes of different kinds of particles may also have a bias when the statistics are poor. Two methods of reducing this bias have been proposed.

1984-12-15

35

Spread spectrum acquisition and tracking performance for Shuttle communication links  

Science.gov (United States)

The spread spectrum acquisition and tracking performance for the Shuttle S-band and Ku-band communication links are analyzed and compared to test results. The S-band link requirements are more severe than those of the Ku-band links, hence, different despreader designs were developed for the two systems. The S-band despreader acquires pseudonoise code lock by examining all possible code phases in half chip steps while the Ku-band despreader acquires pseudonoise code lock by continuously sweeping a tau-jitter loop. Both despreaders employ a tau-jitter loop for code tracking. The code tracking performance is computed for the tau-jitter loop and compared to that of the more complex delay lock loop.

1978-01-01

36

On the statistical estimation of the lifetimes of charmed particles  

Energy Technology Data Exchange (ETDEWEB)

Various statistical methods for the estimation of the mean lifetimes of charmed particles have been considered. It is shown that the usual estimates of the maximum likelihood in some cases do not exist or may have rather great positive bias, if the statistics are low. Alternative estimates of the mean lifetime tau are discussed. Among them the 'jackknife' estimate of tau is considered. The minimum variance unbiased estimates of the average rate of decay 1/tau have been derived for some particular cases. It is also shown that the usual estimate of the ratio of the mean lifetimes of different kinds of particles may alos have a bias when the statistics are poor. Two methods of reducing this bias have been proposed. (orig.).

1984-12-15

37

The radiosensitivity of spermatogonial stem cells in C3H/101 F[sub 1] hybrid mice  

Energy Technology Data Exchange (ETDEWEB)

The radiosensitivity of spermatogonial stem cells of C3H/HeHx101/H F[sub 1] hybrid mice was determined by counting undifferentiated spermatogonia at 10 days after X-irradiation. During the spermatogenic cycle, differences in radiosensitivity were found, which were correlated with the proliferative activity of the spermatogonial stem cells. In stage VIII[sub irr], during quiescence, the spermatogonial stem cells were most radiosensitive with a D[sub 0] of 1.4 Gy. In stages XI[sub irr]-V[sub irr], when the cells were proliferatively active, the D[sub 0] was about 2.6 Gy. Based on the D[sub 0] values for sensitive and resistant spermatogonia and on the D[sub 0] for the total population, a ratio of 45:55% of sensitive to resistant spermatogonial stem cells was estimated for cell killing. When the present data were compared with data on translocation induction obtained in mice of the same genotype, a close fit was obtained when the translocation yield (Y; in % abnormal cells) after a ...

1993-12-01

38

Observations of late-type young stars in the Rho Oph dark cloud  

Energy Technology Data Exchange (ETDEWEB)

We present photoelectric BVRI photometry for 16 T Tau and related stars in the Rho Oph dark cloud, as well as vidicon spectroscopic observations for nine stars. The color excesses of these stars favor circumstellar dust shells as the source of the observed infrared excesses.

1980-04-01

39

A universal CAMAC coincidence circuit  

International Nuclear Information System (INIS)

A universal CAMAC-coincidence circuit is described. All basic parameters are controlled in a wide range from the CAMAC dataway: the coincidence resolving time (2tau) from 1 ns to 10 #mu#s and the anticoincidence resolving time from 10 ns to 10 #mu#s. (Auth.).

40

String thermal tachyons as multiparticle instabilities  

International Nuclear Information System (INIS)

The bosonic string on R"2"5xS"1 has a series of states turning tachyonic at radii implying T=IT_H. We employ the B picture to examine these thermal states in the one-loop free energy and find them in various combinations, factorizing towards rational points on the real line boundary of the fundamental domain B: (-1/2tau# #<=# 1/2, Im #tau# #>=# 0). These thermal tachyons are interpreted as signaling Hagedorn instabilities against the production of an l-highly-excited-identical-strings state, which gives a relation between the one-loop partition function and l-point functions. (orig.).

41
42

The ternary system cerium-palladium-silicon  

Science.gov (United States)

Phase relations in the ternary system Ce-Pd-Si have been established for the isothermal section at 800 deg. C based on X-ray powder diffraction and EMPA techniques on about 130 alloys, which were prepared by arc-melting under argon or powder reaction sintering. Eighteen ternary compounds have been observed to participate in the phase equilibria at 800 deg. C. Atom order was determined by direct methods from X-ray single-crystal counter data for the crystal structures of tau{sub 8}-Ce{sub 3}Pd{sub 4}Si{sub 4} (U{sub 3}Ni{sub 4}Si{sub 4}-type, Immm; a=0.41618(1), b=0.42640(1), c=2.45744(7) nm), tau{sub 16}-Ce{sub 2}Pd{sub 14}Si (own structure type, P4/nmm; a=0.88832(2), c=0.69600(2) nm) and also for tau{sub 18}-CePd{sub 1-x}Si{sub x} (x=0.07; FeB-type, Pnma; a=0.74422(5), b=0.45548(3), c=0.58569(4) nm). Rietveld refinements established the atom arrangement in the structures of tau{sub 5}-Ce{sub 3}PdSi{sub ...

2009-09-15

43

DYNAMICS OF SOLIDS IN THE MIDPLANE OF PROTOPLANETARY DISKS: IMPLICATIONS FOR PLANETESIMAL FORMATION  

International Nuclear Information System (INIS)

We present local two-dimensional and three-dimensional hybrid numerical simulations of particles and gas in the midplane of protoplanetary disks (PPDs) using the Athena code. The particles are coupled to gas aerodynamically, with particle-to-gas feedback included. Magnetorotational turbulence is ignored as an approximation for the dead zone of PPDs, and we ignore particle self-gravity to study the precursor of planetesimal formation. Our simulations include a wide size distribution of particles, ranging from strongly coupled particles with dimensionless stopping time #tau#_s #ident to# #OMEGA#t_s_t_o_p = 10"-"4 (where #OMEGA# is the orbital frequency, t_s_t_o_p is the particle friction time) to marginally coupled ones with #tau#_s = 1, and a wide range of solid abundances. Our main results are as follows. (1) Particles with #tau#_s #approx#> 10"-"2 actively participate in the streaming instability (SI), generate ...

2010-10-20

44

The analysis of biological and environmental samples for lead by photon activation  

International Nuclear Information System (INIS)

... activation analysis biological materials bremsstrahlung environment lead lead

45

Tau Boo b: Hunting for reflected starlight  

CERN Document Server

Aims. We attempt to detect starlight reflected from the hot Jupiter orbiting the main-sequence star Tau Boo, in order to determine the albedo of the planetary atmosphere, the orbital inclination of the planetary system and the exact mass of the planetary companion. Methods. We analyze high-precision, high-resolution spectra, collected over two half nights using UVES at the VLT/UT2, by way of data synthesis. We interpret our data using two different atmospheric models for hot Jupiters. Results. Although a weak candidate signal appears near the most probable radial velocity amplitude, its statistical significance is insufficient for us to claim a detection. However, this feature agrees very well with a completely independently obtained result by another research group, which searched for reflected light from Tau Boo b. As a consequence of the non-detection of reflected light, we place upper limits to the planet-to-star flux ratio at the 99.9% ...

2010-01-01

46

Magnetospheric Emissions from the Planet Orbiting tau Boo: A Multi-Epoch Search  

CERN Document Server

All of the solar system gas giants produce electron cyclotron masers, driven by the solar wind impinging on their magnetospheres. Extrapolating to the planet orbiting tau Boo, various authors have predicted that it may be within the detection limits of the 4-meter wavelength (74 MHz) system on the Very Large Array. This paper reports three epochs of observations of tau Boo. In no epoch do we detect the planet; various means of determining the upper limit to the emission yield single-epoch limits ranging from 135 to 300 mJy. We develop a likelihood method for multi-epoch observations and use it to constrain various radiation properties of the planet. Assuming that the planet does radiate at our observation wavelength, its typical luminosity must be less than about 10^{16} W, unless its radiation is highly beamed into a solid angle Omega << 1 sr. While within the range of luminosities predicted by various authors for this planet, this value ...

2007-01-01

47

Bern-Kosower rule for scalar QED  

International Nuclear Information System (INIS)

We derive a full Bern-Kosower-type rule for scalar QED starting from quantum field theory: we derive a set of rules for calculating S-matrix elements for any processes at any order of the coupling constant. A gauge-invariant set of diagrams in general is first written in the world line path-integral expression. Then we integrate over x(#tau#), and the resulting expression is given in terms of a correlation function on the world line left-angle x(#tau#)x(#tau#"')right-angle. Simple rules to decompose the correlation function into basic elements are obtained. A gauge transformation known as the integration by parts technique can be used to reduce the number of independent terms before integration over proper-time variables. The surface terms can be omitted provided the external scalars are on shell. Also, we clarify correspondence to the conventional Feynman rule, which enabled us to avoid any ambiguity coming from the infinite dimensionality of ...

48

Atmospheric lifetimes and ozone depletion potentials of methyl bromide (CH3Br) and dibromomethane (CH2Br2)  

Energy Technology Data Exchange (ETDEWEB)

The rate coefficients for the reactions of OH radical with CH3Br and CH2Br2 were measured as functions of temperature using the laser photolysis - laser induced fluorescence method. This data was incorporated into a semiempirical model (Solomon et al., 1992) and a 2D model to calculate the steady-state ozone depletion potentials (ODP) and atmospheri lifetimes, tau, with greatly improved accuracy as compared to earlier studies. The calculated ODPs and tau are 0.65 and 1.7 years and 0.17 and 0.41 years for CH3Br and CH2Br2, respectively, using the semiempirical model. These lifetimes agree well with those calculated using a 2D model. This study better quantifies the ODPs and tau of these species which are needed inputs for discussion of possible regulation of human emissions currently under international considerations. 29 refs.

1992-10-01

49

A Direct Precision Measurement of the Intergalactic Lyman-alpha Opacity at 2  

CERN Document Server

We directly measure the evolution of the intergalactic Lyman-alpha effective optical depth, tau_eff, over the redshift range 2 is <1% at z=2, 4% at z=3, and 12% at z=4. Previous measurements of tau_eff at 3tau_eff=0.0018(1+z)^3.92, when metals are left in), particularly near z=3.2. The observed downward departure is statistically ...

2007-01-01

50

Spontaneous resistance fluctuations and their evolution near the threshold in o-TaS_3 below the liquid-nitrogen temperature  

International Nuclear Information System (INIS)

It is found that below 80 K o-TaS_3 demonstrates spontaneous resistance fluctuations growing when the temperature is decreasing. The average relaxation time, #tau#_0, obtained from the noise spectra demonstrates activated behavior, #tau#_0 #propor to# exp(W/T), W #approx# 1300 K for 50 < or #approx# T < or #approx# 70 K. In the vicinity of the threshold the average frequency of the fluctuations, f_0, grows with increasing the voltage, revealing onset of the Froehlich current. log(f_0) is found to be proportional to the increase of conductivity. We conclude that the main source of the resistance fluctuations are thermally-assisted jumps of dislocations of the charge-density waves. (orig.).

1993-06-01

51

Single dilepton production at e"+e"-, e#gamma#, and #gamma##gamma# colliders  

International Nuclear Information System (INIS)

We calculate the cross sections for the single production of doubly charged dileptons, both scalar and vector, at e"+e"-, e#gamma#, and #gamma##gamma# colliders at #sq root#s =500 GeV and 1 TeV. The e#gamma# mode is by far the most promising---dileptons whose coupling is as weak as #approx#10"-"4#alpha#_e_m can be observed, for masses virtually up to the kinematic limit. Dileptons of mass up to #sq root#s can also be seen in e"+e"- and #gamma##gamma# colliders, for couplings of order #alpha#_e_m. In all three colliders, most of the cross section comes from events in which the only particles detected are e"-e"- (or #mu#"-#mu#"- or #tau#"-#tau#"-), the decay products of the dilepton, yielding an unmistakable experimental signature.

52

Resonant CP violation in MSSM Higgs production and decay at {gamma}{gamma} colliders  

Energy Technology Data Exchange (ETDEWEB)

We study CP-violating phenomena in the production, mixing and decay of a coupled system of CP-violating neutral Higgs bosons at {gamma}{gamma} colliders, assuming a Minimal Supersymmetric Standard Model (MSSM) Higgs sector in which CP violation is radiatively induced by phases in the soft supersymmetry-breaking gaugino masses and third-generation trilinear squark couplings. We discuss CP asymmetries in the production and decays of {mu}{sup +}{mu}{sup -}, {tau}{sup +}{tau}{sup -}, b-bar b and t-bar t pairs. We find large asymmetries when two (or all three) neutral Higgs bosons are nearly degenerate with mass differences comparable to their decay widths, as happens naturally in the CP-violating MSSM for values of tan{beta}-bar 5 (30) and large (small) charged Higgs-boson masses.

2005-07-04

53

Resonant CP violation in MSSM Higgs production and decay at #gamma##gamma# colliders  

International Nuclear Information System (INIS)

We study CP-violating phenomena in the production, mixing and decay of a coupled system of CP-violating neutral Higgs bosons at #gamma##gamma# colliders, assuming a Minimal Supersymmetric Standard Model (MSSM) Higgs sector in which CP violation is radiatively induced by phases in the soft supersymmetry-breaking gaugino masses and third-generation trilinear squark couplings. We discuss CP asymmetries in the production and decays of #mu#"+#mu#"-, #tau#"+#tau#"-, b-bar b and t-bar t pairs. We find large asymmetries when two (or all three) neutral Higgs bosons are nearly degenerate with mass differences comparable to their decay widths, as happens naturally in the CP-violating MSSM for values of tan#beta#-bar 5 (30) and large (small) charged Higgs-boson masses.

2005-07-04

54

Radiative Breaking of Gauge Symmetries in the MSSM and in its Extensions  

CERN Document Server

The radiative electroweak symmetry breaking, the b-\\tau Yukawa and gauge couplings unification in the MSSM and its SU(5) extensions are studied in detail. In the framework of the two-loop renormalization group equations both low- and high-energy threshold effects are included. In the case of the minimal SU(5), the values of \\alpha_s obtained are somewhat larger than the experimental average. The Peccei-Quinn version of the missing-doublet SU(5) model generally predicts smaller values of \\alpha_s and b-\\tau unification, in excellent agreement with all low energy experimental data. We also study the generation of the GUT scale through radiative corrections in the context of an R-symmetric ``flipped" SU(5) x U(1)_X model and we find that this is possible in a certain range of values of the parameter space.

1998-01-01

55

Optimized pulse sequences for the suppression of decoherence in quantum information  

International Nuclear Information System (INIS)

The dynamical decoupling (DD) aims at suppressing the decoherence by means of coherent control pulses. Even if devices exist where instantaneous pulses are an adequate approximation, experimentally a finite duration #tau#_p and a bounded amplitude are inevitable. They are the cause of additional errors which can be corrected by designing the pulse shape appropriately. The new pulse has the overall effect of an ideal, instantaneous pulse with the advantage of decoupling the spin (or qubit) from the bath up to the order O(#tau#_p"3). The limitation of the no-go theorem for #pi# pulses is avoided. Hence, the Uhrig sequence (UDD), originally thought for ideal #pi# pulses, works also for bounded control Hamiltonians. Numerical simulations show that concatenated sequences of real pulses are effective against general decoherence.

2010-03-21

56

Aerosol characteristics over coastal regions of the Arabian Sea  

Energy Technology Data Exchange (ETDEWEB)

From aerosol spectral optical depths ({tau}{sub p{lambda}}) at wavelengths in the range 380 to 1025 nm estimated at different locations in the near and far coastal regions of the Arabian sea adjoining the western coast of central India, the spatial and spectral characteristics of coastal aerosols and the effect of the proximity to the (urban) continent are investigated. The Aangstroem parameters are deduced from {tau}{sub p{lambda}} values. A significant increase, both in aerosol optical depths at shorter (visible) wavelengths ({lambda} {<=} 600 nm) and the Aangstroem wavelength exponent are observed in the near coastal regions, suggesting an increase in the (relative) concentration of sub micron particles, apparently of anthropogenic origin. The Aangstroem turbidity coefficient remains nearly steady spatially, indicating a (spatially) uniform loading of large particles. 31 refs, 10 figs, 1 tab

1997-09-01

57

Production and decay of scalar top squarkonium bound states  

International Nuclear Information System (INIS)

In this paper we discuss possible signatures for the production of scalar t_1t_1"* (top squarkonium) bound states #sigma#_t_1 at hadron colliders, where t_1 is the lighter scalar top eigenstate. We first study the decay of #sigma#_t_1; explicit expressions are given for all potentially important decay modes. If t_1 has unsuppressed two-body decays, they will always overwhelm the annihilation decays of #sigma#_t_1. Among the latter, we find that usually either the gg or hh final state dominates, depending on the size of the off-diagonal entry of the top squark mass matrix; h is the lighter neutral scalar Higgs boson of the minimal supersymmetric model. If m_#sigma#_t happens to be close to the mass of one of the neutral scalar Higgs bosons, Q bar Q final states dominate (Q=b or t). W"+W"- and ZZ final states are subdominant. We argue that #sigma#_t_1#->##gamma##gamma# decays offer the best signal for top squarkonium production at hadron colliders. The Fermilab Tevatron should be able ...

58

Probing quantum gravity using photons from a flare of the active galactic nucleus Markarian 501 observed by the MAGIC telescope  

Energy Technology Data Exchange (ETDEWEB)

We analyze the timing of photons observed by the MAGIC telescope during a flare of the active galactic nucleus Mkn 501 for a possible correlation with energy, as suggested by some models of quantum gravity (QG), which predict a vacuum refractive index {approx_equal}1+(E/M{sub QGn}){sup n}, n=1,2. Parametrizing the delay between {gamma}-rays of different energies as {delta}t={+-}{tau}{sub l}E or {delta}t={+-}{tau}{sub q}E{sup 2}, we find {tau}{sub l}=(0.030{+-}0.012) s/GeV at the 2.5-{sigma} level, and {tau}{sub q}=(3.71{+-}2.57)x10{sup -6} s/GeV{sup 2}, respectively. We use these results to establish lower limits M{sub QG1}>0.21x10{sup 18} GeV and M{sub QG2}>0.26x10{sup 11} GeV at the 95% C.L. Monte Carlo studies confirm the MAGIC sensitivity to propagation effects at these levels. Thermal plasma effects in the source are negligible, but we cannot exclude the importance of some other ...

2008-10-16

59

Metastability and dynamics of the shock-induced phase transition in iron  

Energy Technology Data Exchange (ETDEWEB)

The shock-induced {alpha}(bcc){r_arrow}{var_epsilon}(hcp) transition in iron begins at 13 GPa on the Hugoniot. In the two-phase region above 13 GPa, the Hugoniot lies well above the equilibrium surface defined by G{sub {alpha}}=G{sub {var_epsilon}}, with G the Gibbs free energy. Also, the phase transition relaxation time {tau} is uncertain, with estimates ranging from {lt}50 ns to {approx}180 ns. Here we present an extensive study of these important aspects, metastability and dynamics, of the {alpha}-{var_epsilon} transition in iron. Our primary theoretical tools are (a) accurate theoretically based free energies for {alpha} and {var_epsilon} phases of iron and (b) accurate calculations of the wave evolution following planar impacts. We define metastable surfaces for forward and reverse transitions by the condition that the thermodynamic driving force G{sub {alpha}}{minus}G{sub {var_epsilon}} is just balanced by an opposing force resulting from elastic stresses, ...

1997-02-01

60

High energy physics  

International Nuclear Information System (INIS)

The research of the CELLO collaboration is reviewed. After a description of the CELLO detector tests of QCD and hadronic final states by determination of the strong coupling constant and studies of inclusive production of electrons and muons in multihadronic events in e"+e"- annihilation are described. Then studies of deep inelastic e#gamma# scattering with lepton pair production and the study of the structure function of the photon are briefly described. Finally studies on QED processes are described together with tau decays. (HSI).

1983-11-01

61

Final State QED Bremsstrahlung in Resonance Decays and Detector Level Universality: Phenomenological Precision Tools  

International Nuclear Information System (INIS)

The status of Monte Carlo system for the simulation of Bremsstrahlung in arbitrary decays and for the decay itself of #tau# -lepton is reviewed. During the last #tau# -lepton conference in 2010 several developments of the last two years have been presented: (i) For the TAUOLA Monte Carlo generator of #tau# -lepton decays, automated and simultaneous use of many versions of form-factors for the calculation of optional weights for fits was developed and checked to work in Belle and BaBar software environment. On-going work on alternative parameterizations of hadronic decays is presented too. (ii) The TAUOLA universal interface based on HepMC (the C++ event record) is now public. A similar interface for PHOTOS is now also public. (iii) Extension of PHOTOS Monte Carlo for QED Bremsstrahlung in decays featuring kernels based on complete first order matrix element are gradually becoming widely available thanks to properties of the ...

2011-07-01

62

Effective Lagrangian description of Higgs mediated flavor violating electromagnetic transitions: Implications on lepton flavor violation  

International Nuclear Information System (INIS)

Higgs mediated flavor violating electromagnetic interactions, induced at the one-loop level by a nondiagonal Hf_if_j vertex, with f_i and f_j charged leptons or quarks, are studied within the context of a completely general effective Yukawa sector that comprises SU_L(2)xU_Y(1)-invariant operators of up to dimension-six. Exact formulae for the one-loop #gamma#f_if_j and #gamma##gamma#f_if_j couplings are presented and their related processes used to study the phenomena of Higgs mediated lepton flavor violation. The experimental limit on the #mu##->#e#gamma# decay is used to derive a bound on the branching ratio of the #mu##->#e#gamma##gamma# transition, which is 6 orders of magnitude stronger than the current experimental limit. Previous results on the #tau##->##mu##gamma# and #tau##->##mu##gamma##gamma# decays are reproduced. The possibility of detecting signals of lepton flavor violation at #gamma##gamma# colliders is explored ...

2009-05-01

63

Determination of reactor kinetic parameters in a two-core reactor  

Energy Technology Data Exchange (ETDEWEB)

The kinetic parameters, ..cap alpha.. the coupling coefficient and tau-bar the mean neutron transit time have been determined using a reactor oscillator on the coupled-core of the Queen Mary College research reactor. By using correlation techniques it has proved possible to use detectors small enough to be inserted in the fuel tanks. It is shown that the simplified Baldwin model with one-group diffusion theory is inadequate to describe the kinetic behaviour and the experimentally-determined parameters are dependent upon the positioning of the detectors.

1982-01-01

64

Effect of dietary constituents on the absorption of lead in the human  

International Nuclear Information System (INIS)

... biological effects body burden diet intestinal absorption lead lead 203 man

1983-03-01

65

Transfer of lead through the rats intestinal wall  

International Nuclear Information System (INIS)

... females in vitro intestines lead 203 mucous membranes radionuclide kinetics

66

NONDESTRUCTIVE DETERMINATION OF AIRBORNE LEAD ...  

Science.gov (United States)

... NONDESTRUCTIVE DETERMINATION OF AIRBORNE LEAD PARTICULATES BY THE RADIONUCLIDE X-RAY FLUORESCENCE ANALYSIS. ...

67

Lead-203 for skeletal imaging  

International Nuclear Information System (INIS)

... biological variability body distribution kidneys labelled compounds lead 203

68

The effect of welding parameters on hydrogen distribution in pipeline welds  

Energy Technology Data Exchange (ETDEWEB)

There is currently considerable interest in identifying and quantifying the effects of welding procedure parameters and steel composition factors on the risk of cracking in pipeline girth welds that may be experienced during winter construction. Although low ambient temperatures, that may be experienced during winter construction, are generally assumed to increase the risk of cracking there has been little work to quantify the effects and to suggest how welding procedures should be modified for winter conditions. The present work was undertaken to calculate the effects of changes in welding parameters on the thermal cycle and the diffusion of hydrogen for a typical pipeline girth weld. A simple analytical method and the finite element method (FEM) were used. Both methods gave similar results but the simple method was very sensitive to the value of heat transfer coefficient. The results showed that the relation between the hydrogen diffusion parameter (tau) and ...

1990-03-01

69

Rheology of zirconia suspensions in a nonpolar organic medium  

Energy Technology Data Exchange (ETDEWEB)

Three dispersants (stearic acid, oleic acid, and poly-(12-hydroxystearic acid)) are compared for their ability to produce low-viscosity suspensions of zirconia in kerosene. Rheological measurements and sediment packing density measurements show that poly(12-hydroxystearic acid) is a better dispersant than stearic acid or oleic acid; this is explained in terms of the longer tail of the poly-(12-hydroxystearic acid) surfactant molecule. The amount of dispersant can be optimized to reduce viscosity and yield point of the suspension, and to eliminate thixotropic hysteresis. The use of a dispersion medium of lower viscosity than the dispersant makes it easy to detect when complete monolayer coverage has been achieved. The loss of pseudoplasticity, brought about by a higher degree of deflocculation, can be recovered by increasing the volume fraction of solids of a suspension and this is beneficial in the plastic forming of ceramics. Rheological measurements showed that these suspensions ...

1995-12-01

70

Planetpol polarimetry of the exoplanet systems 55 Cnc and tau Boo  

CERN Document Server

We present very sensitive polarimetry of 55 Cnc and tau Boo in an attempt to detect the partially polarised reflected light from the planets orbiting these two stars. 55 Cnc is orbited by a hot Neptune planet (55 Cnc e) at 0.038 AU, a hot Jupiter planet (55 Cnc b) at 0.11 AU, and at least 3 more distant planets. The fractional polarisation of this star is very stable, with a standard deviation in the nightly averaged Stokes Q/I and U/I parameters of 2.2x10^{-6}. We derive upper limits on the geometric albedo, A_G and planetary radius using Monte Carlo multiple scattering simulations of a simple model atmosphere. We assume Rayleigh-like scattering and polarisation behaviour (scaled by the maximum polarisation, p_m at 90 degrees) and pressure insensitive extinction. Atmospheres in which multiple scattering plays only a small role have an almost linear relation between polarisation and A_G. In this case, the 4 sigma upper limits are A_G<0.13(R/1.2 ...

2008-01-01

71

Multicast Capacity Scaling of Wireless Networks with Multicast Outage  

CERN Document Server

Multicast transmission has several distinctive traits as opposed to more commonly studied unicast networks. Specially, these include (i) identical packets must be delivered successfully to several nodes, (ii) outage could simultaneously happen at different receivers, and (iii) the multicast rate is dominated by the receiver with the weakest link in order to minimize outage and retransmission. To capture these key traits, we utilize a Poisson cluster process consisting of a distinct Poisson point process (PPP) for the transmitters and receivers, and then define the multicast transmission capacity (MTC) as the maximum achievable multicast rate times the number of multicast clusters per unit volume, accounting for outages and retransmissions. Our main result shows that if $\\tau$ transmission attempts are allowed in a multicast cluster, the MTC is $\\Theta\\left(\\rho k^{x}\\log(k)\\right)$ where $\\rho$ and $x$ are functions of $\\tau$ depending ...

2010-01-01

72

Radon grab sampling in water by means of radon transfer in activated charcoal collectors  

Energy Technology Data Exchange (ETDEWEB)

The proposed portable device is suitable for radon surveys in water-bearing strata. It allows a complete transfer in activated charcoal canisters of radon dissolved in water collected with a 0.61 bottle. The detection is performed in laboratory with a low background {gamma}-ray spectrometer utilizing 3{sup x}3{sup N}aI({tau}I) scintillator only after about ten hours. This time is necessary to let radon be uniformly distributed within the activated charcoal.

1999-08-01

73

APERTURE SYNTHESIS IMAGING OF V892 Tau AND PV Cep: DISK EVOLUTION  

International Nuclear Information System (INIS)

I present a study of two Herbig Ae stars that are in completely different evolutionary stages: V892 Tau and PV Cep. Using sub-arcsecond interferometric observations obtained with the Combined Array for Research in Millimeter-wave Astronomy at #lambda# = 1.3 and 2.7 mm, I have for the first time resolved their disks. I deduce that the 5 Myr old V892 Tau has a low dust opacity index #beta# = 1.1 and a disk mass of #approx#0.03 M_s_u_n. These values correspond to the growth of its dust into large, up to centimeters size, structures. In contrast, the very young (a few x10"5 yr) PV Cep has a quite high opacity index #beta# = 1.75 and a more massive disk 0.8 M_s_u_n. PV Cep has the youngest resolved disk around any Herbig Ae star. Unlike the youngest T Tauri and Class 0 stars, which contain large and processed grains, the young Herbig Ae star, PV Cep, disk contains interstellar-medium-like unprocessed dust. This suggests that PV Cep's dust evolution ...

2010-10-10

74

Toxicological properties of lead.  

UK PubMed Central (United Kingdom)

The pathological effects of lead on the renal, nervous, reproductive, endocrine, and immune systems have been reviewed. Emphasis is placed on reported subclinical effects due to chronic, low-level lead...Full Text Available

1977-08-01

76

The effects of thiamin on lead metabolism: organ distribution of lead 203.  

UK PubMed Central (United Kingdom)

The effect of thiamin on the organ distribution of lead was evaluated in CD-1 mice exposed intragastrically or intraperitoneally to a single dose of lead acetate (100 micrograms) containing 100 microCi...Full Text Available

1992-07-01

80

Phytoremediation Potential of Lead-Contaminated Soil Using Tropical Grasses  

Science.gov (United States)

The global problem concerning contamination of the environment because of human activities is increasing. Most of the environmental contaminants are chemical by-products and heavy metals such as lead (Pb). Lead released into the environment makes its way into the air, soil and water. Lead contribute...

81

Lead and ?-Aminolevulinic Acid Dehydratase Polymorphism: Where Does It Lead? A Meta-Analysis  

UK PubMed Central (United Kingdom)

BackgroundLead poisoning affects many organs in the body. Lead inhibits δ-aminolevulinic acid dehydratase (ALAD), an enzyme with two co-dominantly expressed alleles, ALAD1...Full Text Available

2007-01-01

82

Tracer studies with carrier-free lead-203  

International Nuclear Information System (INIS)

... blood cells in vitro in vivo injection intake lead 203 man renal clearance uptake

1972-07-30

84

Study on the behaviour of cryogenic current leads in the overload regime  

Energy Technology Data Exchange (ETDEWEB)

6 mm diameter current leads made of M1, M3 copper and L62 brass are tested for extension of operation range of current leads supplying superconducting devices submerged into the cryostat. Data characterizing the effect of material purity on lead superheating are obtained. A theoretical model permitting to obtain analytical dependences for calculating the current lead maximum temperature is proposed and the possibility of its decrease by increasing current lead diameter in the hot part is considered.

1982-01-01

85

Lead exposure via drinking water - unnecessary and avoidable  

International Nuclear Information System (INIS)

Despite successful reduction of the general lead exposure, this heavy metal is still a matter of public concern due to the fact that associations with intellectual impairment or delayed puberty are found to correlate with very low lead blood concentrations. Lead in tap water is still an important contribution to lead exposure which may cause health risk for infants. Therefore, lead pipes should be completely sanitated by exchange against pipes made from more healthy materials. (orig.)

86

Lead uptake and lead loss in the fresh water field crab, Barytelphusa guerini, on exposure to organic and inorganic lead  

Energy Technology Data Exchange (ETDEWEB)

Lead is a heavy metal which is widely used in paint industry, pigments, dyes, electrical components and electronics, plastic chemicals and in various other things. Since some of the lead salts are soluble in water, lead presents a potential threat to aquatic organisms. Studies dealing with invertebrates include those on mortality, growth and lead uptake in Lymnaea palustris and bioaccumulation of heavy metals in oysters and mussels. Little information exists regarding the effect of lead on the fresh water crustaceans. Hence the present investigation has been undertaken to study the uptake and loss of lead on exposure to subtoxic levels or organic and inorganic lead.

1987-07-01

87

Effect of dose on lead retention and distribution in suckling and adult female mice  

Energy Technology Data Exchange (ETDEWEB)

Single doses of lead (trace to 445 mg/kg) were administered per os to suckling and adult mice. Both groups exhibited dose-independent lead retention when doses of 4 to 445 mg/kg were administered. However, developmental differences in the fraction of initial dose (FID) retained were evident for all doses administered. A much larger FID was retained in both age groups following administration of carrier-free /sup 203/Pb. The results are consistent with a mechanism of gastrointestinal lead absorption comprising two or more processes. Developmental differences were also observed in organ lead concentration relative to whole body concentration for kidneys, skull and brain 6 days following lead administration. Lead retentions (relative to whole body retention) in brain and in bone were linearly related to dose of lead administered in both ...

1980-01-01

88

Top quark rare three-body decays in the littlest Higgs model with T-parity  

CERN Document Server

In the littlest Higgs model with T-parity (LHT), the mirror quarks have flavor structures and will contribute to the top quark flavor changing neutral current. In this work, we perform an extensive investigation of the top quark rare three-body decays $t\\rightarrow cVV (V=\\gamma,Z,g)$ and $t\\rightarrow cf\\bar{f} (f=b,\\tau,\\mu,e)$ at one-loop level. Our results show that the branching ratios of $t\\rightarrow cgg$ and $t\\rightarrow cb\\bar{b}$ could reach $\\mathcal {O}(10^{-3})$ in the favorite parameter space of the littlest Higgs model with T-parity, which implies that these decays may be detectable at the LHC or ILC, while for the other decays, their rates are too small to be observable at the present or future colliders.

2011-01-01

89

Theoretical search for optimal pump parameters for observing spontaneous radiation amplification on the {lambda}=41.8-nm transition of Xe IX in plasma  

Science.gov (United States)

Based on a collisional-radiative model, an atomic-kinetic calculation of the gains on the 41.8-nm transitions of Pd-like xenon was performed for the plasma produced due to the interaction of a femtosecond laser pulse with gaseous xenon. The gains g(z,{tau}) averaged over the spatial and temporal coordinates were compared with the known gains which had been measured experimentally in Xe{sup 8+}. The amplification was shown to occur under the conditions of ionisation of the working ions, and the time of output radiation saturation depends on the time of Xe{sup 8+} transformation to higher-ionised ions. Our theoretical investigation enables determining the optimal pump parameters, at which the product of the gain g by the active medium length L is about 20, which exceeds the experimental gL value. (active media)

2004-11-30

90

Study of oxygen diffusion in YBaCuO by isothermal internal friction. Etude par frottement interieur isotherme de la diffusion de l'oxygene dans YBaCuO  

Energy Technology Data Exchange (ETDEWEB)

The elastic behaviour of YBaCuO specimens has been studied by very low-frequency isothermal internal-friction measurements. A relaxation peak is observed which is attributed to oxygen atom jumps, between A(1/2 0 0) and B(0 1/2 0) sites, in the CuO planes of the orthorhombic phase. A limit relaxation time {tau}{sub 0}, 2.6 {center dot} 10{sup -15}s, and an activation energy, 1.3eV, have been obtained from the shift of the maximum damping frequency observed when the measurement temperature is changed. The proposed values for the limit relaxation time and the activation energy are in good agreement with those previously proposed in the literature.

1992-02-07

91

Spin dynamics in Ho{sub 2}Ru{sub 2}O{sub 7}  

Energy Technology Data Exchange (ETDEWEB)

The spin relaxation processes within the pyrochlore Ho{sub 2}Ru{sub 2}O{sub 7} have been investigated by neutron scattering and bulk property techniques. A single-ion process, that is thermally activated, dominates the spin-spin relaxation spectrum above 2 K. Assuming Arrhenius behaviour, we found an activation energy {delta} = (329 {+-} 6) K and characteristic relaxation time {tau}{sub 0} (5.2 {+-} 0.3) x 10{sup -12} s in the paramagnetic state, akin to those found in the spin ice, Ho{sub 2}Ti{sub 2}O{sub 7}. Atlow temperature (T<95 K) the activation energy lowers and below 20 K the entropy and ac susceptibility are similar to that observed in other spin ice compounds within a 10 kOe field.

2005-11-09

92

Spin dynamics in Ho_2Ru_2O_7  

International Nuclear Information System (INIS)

The spin relaxation processes within the pyrochlore Ho_2Ru_2O_7 have been investigated by neutron scattering and bulk property techniques. A single-ion process, that is thermally activated, dominates the spin-spin relaxation spectrum above 2 K. Assuming Arrhenius behaviour, we found an activation energy #DELTA# = (329 #+-# 6) K and characteristic relaxation time #tau#_0 (5.2 #+-# 0.3) x 10"-"1"2 s in the paramagnetic state, akin to those found in the spin ice, Ho_2Ti_2O_7. Atlow temperature (T<95 K) the activation energy lowers and below 20 K the entropy and ac susceptibility are similar to that observed in other spin ice compounds within a 10 kOe field.

2005-11-09

93

Simple isolation of polonium-210 from silver  

Energy Technology Data Exchange (ETDEWEB)

Over the last several years considerable concern has been expressed regarding the potential detrimental effects of radon and radon progeny on our health. The complex nature of the radon decay scheme, which involves the emission of a variety of radiations including several [alpha] particles, [beta] particles, and [gamma]-rays, does not lend itself to clear delineation of the biological effects of the [alpha] particles alone. Polonium-210, the terminal radionuclide of the radon decay series, is useful for this purpose because it has a relatively long shelf-life ([tau][sub 1/2] = 138 d), and it only emits a single 5.3 MeV [alpha] particle in its decay to stable [sup 206]Pb. Accordingly, it has been used extensively in radiobiological studies with incorporated radionuclides. The radionuclide [sup 210]Po is produced in a reactor from [sup 209]Bi. (Author).

1994-05-01

94

Search for Neutron-Antineutron Oscillations Using Multiprong Events in Soudan 2  

CERN Document Server

We have searched for neutron-antineutron oscillations using the 5.56 fiducial kiloton-year exposure of the Soudan 2 iron tracking calorimeter. We require candidate n-nbar occurrences to have .GE. 4 prongs (tracks and showers) and to have kinematics compatible with nbar-N annihilation within a nucleus. We observe five candidate events, with an estimated background from atmospheric neutrino and cosmic ray induced events of 4.5 \\pm 1.2 events. Previous experiments with smaller exposures observed no candidates, with estimated background rates similar to this experiment. We set a lifetime lower limit for oscillation time in iron: T_A(Fe) > 7.2x10^{31} years. The corresponding lower limit for oscillation of free neutrons is \\tau_{n-nbar} > 1.3x10^8 seconds.

2002-01-01

95

Olfactory memory is impaired in a triple transgenic model of Alzheimer disease  

British Library Electronic Table of Contents (United Kingdom)

Olfactory memory dysfunctions were investigated in the triple-transgenic murine model of Alzheimer's disease (3x Tg-AD). In the social transmission of food preference test, 3x Tg-AD mice presented severe deficits in odor-based memory, without gross changes in general odor-ability. Ab and tau immunoreactivity was not observed in the primary processing regions for odor, the olfactory bulbs (OBs), whereas marked immunostaining was present in the piriform, entorhinal, and orbitofrontal cortex, as well as in the hippocampus. Our results suggest that the impairment in olfactory-based information processing might arise from degenerative mechanisms mostly affecting higher cortical regions and limbic areas, such as the hippocampus.

2011-01-01

96

Nuclear magnetic moment measurements through hyperfine interactions in highly stripped ions  

International Nuclear Information System (INIS)

Time-differential magnetic moment measurements on the first-excited Isup(#pi#)=2"+ states in "2"0Ne and "2"4Mg with mean lives of 1.0 and 2.1 ps, respectively are described. The lifetime of the latter state was determined simultaneously. A special detection geometry was designed to improve the experimental #gamma#-ray anisotropy measured with finite-size detectors. For "2"0Ne also a time-integral measurement with charge-state separation was performed. The necessary electronics circuitry built to perform these complicated measurements and the plunger assembly with laser interferometer are also described. A magnetic moment measurement of "2"2Ne(2_1"+) with tau=5.0 ps and transient field measurements at low and high recoil velocities are reported. A discussion of possible extensions of the techniques are given. (Auth.).

1975-09-15

97

Multi-stage FEL amplifier with diaphragm focusing line as direct energy driver for inertial confinement fusion  

Energy Technology Data Exchange (ETDEWEB)

An FEL based energy driver for Inertial Confinement Fusion (ICF) is proposed. The key element of the scheme is free electron laser system. Novel technical solutions, namely, using of multichannel, multi-stage FEL amplifier with diaphragm focusing line, reveal a possibility to construct the FEL system operating at radiation wavelength {lambda} = 0.5 {mu}m and providing flush energy E = 1 MJ and brightness 4 x 10{sup 22} W cm{sup -2} sr{sup -1} within steering pulse duration {tau} {approximately} 0.1-2 ns. Total energy efficiency of the proposed ICF energy driver is about of 11% and repetition rate is 40 Hz. It is shown that the FEL based ICF energy driver may be constructed at the present level of accelerator technique R& D.

1995-12-31

98

Global exponential stability of periodic solution for shunting inhibitory CNNs with delays  

Energy Technology Data Exchange (ETDEWEB)

By using the continuation theorem of coincidence degree theory and constructing suitable Lyapunov functions, we study the existence and stability of periodic solution for shunting inhibitory cellular neural networks (SICNNs) with delays x-bar {sub ij}(t)=-a{sub ij}(t)x{sub ij}(t)--bar B{sup kl}-bar Nr(i,j)B{sub ij}{sup kl}(t)f{sub ij}(x{sub kl}(t))x{sub ij}(t)--bar C{sup kl}-bar Nr(i,j)C{sub ij}{sup kl}(t)g{sub ij}(x{sub kl}(t-{tau}{sub kl}))x{sub ij}(t)+L{sub ij}(t)

2005-03-28

99

Global exponential stability of periodic solution for shunting inhibitory CNNs with delays  

International Nuclear Information System (INIS)

By using the continuation theorem of coincidence degree theory and constructing suitable Lyapunov functions, we study the existence and stability of periodic solution for shunting inhibitory cellular neural networks (SICNNs) with delays x-bar _i_j(t)=-a_i_j(t)x_i_j(t)--bar B"k"l-bar Nr(i,j)B_i_j"k"l(t)f_i_j(x_k_l(t))x_i_j(t)--bar C"k"l-bar Nr(i,j)C_i_j"k"l(t)g_i_j(x_k_l(t-#tau#_k_l))x_i_j(t)+L_i_j(t).

2005-03-28

100

Do $\\psi$(4040), $\\psi$(4160) signal hybrid charmonium?  

CERN Document Server

We suggest that \\psi (4040) and \\psi (4160) are strong mixtures of ground state hybrid charmonium at \\sim 4.1 GeV and the \\psi (3S) of conventional charmonium. The \\Gamma^{e^+e^-}, masses and total widths of the \\psi(4040) and \\psi(4160) are in accord with this hypothesis. Their hadronic decays are predicted to be dominated by the \\psi (3S) component and hence are correlated. In particular we find a spin counting relation \\Gamma (4160 \\rightarrow D_sD_s^*) \\sim 4 \\Gamma (4040 \\rightarrow D_sD_s) due to their common \\psi(3S) component. For D and D^* production, using \\psi(4040) branching ratios as input, we predict that the decay pattern of the \\psi(4160) will be very different from that of the \\psi(4040). These predictions may be tested in historical data from SPEAR, BES or at future Tau-Charm Factories.

1995-01-01

101

An identification method of positron production in laser beam interaction with targets  

Energy Technology Data Exchange (ETDEWEB)

A simple electromagnetic transport system was constructed to identify very rare positrons produced in a powerful laser beam interaction with a target. Testing experiments were carried out with CO[sub 2]-laser (10[sup 12] W/cm[sup 2]) beam pulses ([tau] = 50 ns, f = 0.01 Hz) focused on the copper target, as well as with a 96 MeV alpha-particle beam irradiated carbon target. The results showed that the developed system could be effectively used for positron identification and evaluation of their energy by means of a time-of-flight method. The computerized system to deal with this problem, together with others related to the power laser beam interaction with targets, has been constructed. (orig.).

1992-10-01

102

Phase-out of leaded gasoline: a prescription for Lebanon  

International Nuclear Information System (INIS)

Full text.Lead is a toxic heavy metal. Nevertheless, it has been mined and used for more than 800 years. Among the different contemporary sources of lead pollution, emissions from the combustion of leaded gasoline is of particular concern, as it can constitutes more than 90 percent of total lead emissions into the atmosphere in congested urban areas. Concentrations of lead in air and blood are strongly correlated with gasoline lead content and traffic volume. As a result of the increasing awareness about the dangers of lead to human health and the measures to manage urban air pollution, the use of leaded gasoline has been decreasing worldwide. In Lebanon, in the absence of policies to reduce the use of lead in gasoline or to favor the use of unleaded gasoline, leaded gasoline is ...

2000-11-23

103

The independent contribution of bone and erythrocyte lead to urinary lead among middle-aged and elderly men: the normative aging study.  

UK PubMed Central (United Kingdom)

Plasma is the component of blood from which lead is free to cross cell membranes and cause organ toxicity. Plasma lead levels, however, are extremely low and difficult to measure. Urinary lead originates...Full Text Available

1999-05-01

104

Effect of dietary constituents on the gastrointestinal absorption of /sup 203/Pb in man  

Energy Technology Data Exchange (ETDEWEB)

The gastrointestinal absorption of lead was markedly increased in human subjects who had fasted before ingesting lead. Food in the gut was found to reduce lead absorption, and the effect of dietary constituents on /sup 203/Pb absorption was investigated. The greatest reduction in absorption was caused by minerals. This dependence of lead absorption on dietary constituents complicates the establishment of safe levels of lead in food and water.

1983-02-01

105

Characteristics of transplacental lead transfer in rat dams and fetuses  

International Nuclear Information System (INIS)

This study was designed to quantitate the dose resulting from lead exposure during the critical periods of brain development during gestation by determining: (1) if blood lead concentration in rat dams is affected by pregnancy status or duration of lead exposure, (2) if lead concentration in fetuses is associated with the duration of dam exposure, (3) the rates of lead absorption and elimination in pregnant and nonpregnant dams; and (4) the effect that prebreeding exposure on lead kinetics in the dam and upon fetus blood lead concentrations. The results of experiments in which the dams' drinking water contained 50 mg/L lead indicate blood lead levels (after normalizing by water consumption on a body weight basis) of pregnant rats are significantly higher than blood lead levels of ...

106

Theory of mirror machines at high beta  

Science.gov (United States)

The kinetic and guiding center fluid theories of high-..beta.. plasma containment in mirror machines have been developed in a number of self-consistent models. The geometrical effects of magnetic field and ambipolar potential variation have been incorporated in a bounce-averaged Fokker-Planck code which shows that the square-well model somewhat overestimates the n tau and ..beta.. achievable in a mirror field. Simple analytic approximations to the resulting pressure profiles have been incorporated in three-dimensional fluid-equilibrium codes which show the effect of coil geometry on the maximum ..beta... Strongly curved vacuum fields allow higher ..beta.., but short plasmas in weakly curved fields tend to reverse the curvature locally before the mirror-mode limit is reached. Adiabaticity of particle orbits is described in terms of general formulas, applicable in high-..beta.. plasma equilibria, and is shown to break down close to the mirror-mode limit. Two ...

1976-08-06

107

Higgs particles in the standard model and supersymmetric theories  

International Nuclear Information System (INIS)

This thesis presents a theoretical analysis of the properties of the Higgs bosons in the standard model (SM) and the minimal supersymmetric extension (MSSM), which can be investigated at the LHC and e"+e"- linear colliders. The final goal is the reconstruction of the Higgs potential and thus the verification of the Higgs mechanism. MSSM Higgs boson production processes at future #gamma##gamma# colliders are calculated in several decay channels. Heavy scalar and pseudoscalar Higgs bosons can be discovered in the bb final state in the investigated mass range 200 to 800 GeV for moderate and large values of tan#beta#. The #tau#"+#tau#"- channel provides a heavy Higgs boson discovery potential for large values of tan#beta#. Several mechanisms that can be exploited at e"+e"- linear colliders for the measurement of the lifetime of a SM Higgs boson in the intermediate mass range are analysed. In the WW mode, the lifetime of Higgs scalars with masses below #propor to#160 ...

108

Electron-beam-plasma ion source as source of negative fluorine  

Energy Technology Data Exchange (ETDEWEB)

Radioactive ion beams (RIBs) of short-lived isotopes of fluorine are in demand for investigating astrophysical phenomena related to the hot CNO cycle and rp processes responsible for stellar nucleosynthesis. Since negative ion beams are required for injection into tandem electrostatic accelerators, such as the 25 MV tandem accelerator used for post acceleration of RIBs for the Holifield Radioactive Ion Beam Facility (HRIBF) research program at the Oak Ridge National Laboratory (ORNL), efficient, direct-formation F{sup -} ion sources are highly desirable for RIB applications involving this type of post-accelerator. We have conceived and evaluated a direct extraction F{sup -} source for potential RIB applications which is predicated on the reverse polarity operation of a positive electron-beam-plasma target/ion source (EBPTIS) while simultaneously feeding fluorine rich compounds and Cs vapor into the source. The source is found to operate in two separately distinct temperature regimes ...

1997-11-01

109

Roles of lead-binding proteins in mediating lead bioavailability.  

UK PubMed Central (United Kingdom)

The intracellular bioavailability of lead (Pb) at low dosage levels in major target organs such as the kidney and brain appears to be largely determined by complexation with a group of low molecular...Full Text Available

1998-12-01

110

Object Repetition Leads to Local Increases in the Temporal Coordination of Neural Responses  

UK PubMed Central (United Kingdom)

Experience with visual objects leads to later improvements in identification speed and accuracy (“repetition priming”), but generally leads to reductions in neural activity in single-cell...Full Text Available

111

Lead recycling; Namari no recycle  

Energy Technology Data Exchange (ETDEWEB)

In Japan, lead has been widely used for gasoline additives, inorganic chemicals such as pigment, lead pipes/plates, and coating materials of cable. Because of the steady increase in car population and the mounting of environmental concern, lead consumption ratio for lead-acid batteries is tending to increase gradually up to 70% with decreasing the consumption for gasoline additives. This paper describes the recycling of lead-acid batteries in Japan. Since the latter half of FY 1994, the battery manufacturing industry started the new lead recycling system. The recycling ratio of the used lead-acid batteries became 90% in 1996 from 84% in 1994. In near future, it can reach to 95%, the recycling ratio in some European countries. The primary smelting occupies 53%, and the secondary smelting occupies 47%. For the conventional method by secondary ...

1997-12-25

112

Lead content of dried films of domestic paints currently sold in Nigeria  

Energy Technology Data Exchange (ETDEWEB)

Children are at higher risk from lead exposure because their developing neural system is susceptible to its neurotoxic effects. We studied lead levels of paints manufactured in Nigeria in 2006. Lead levels in 5 colors of paints, each from different manufacturers were measured using flame-atomic absorption spectroscopy. We found that 96% of the paints had higher than recommended levels of lead. The mean lead level of paints ranged from 84.8 to 50,000 ppm, with mean of 14,500 ppm and median of 15,800 ppm. The main determinant of lead levels was color of the paint. As lead levels in paint sold in the past years in Nigeria are likely to be at least as high as that currently sold, it is likely that many existing houses contain dangerously high levels of lead. Efforts need to be undertaken to assess the presence of high ...

2007-12-15

113

Effect of lead on erythrocyte membranes.  

UK PubMed Central (United Kingdom)

The effect of blood lead on erythrocyte membrane proteins was studied in 28 workers from a scrap lead refining factory and in 18 controls working in railway construction. Sodium dodecyl sulphate-polyacrylamide...Full Text Available

1983-05-01

114

Effect of Breast Milk Lead on Infant Blood Lead Levels at 1 Month of Age  

UK PubMed Central (United Kingdom)

Nursing infants may be exposed to lead from breast milk, but relatively few data exist with which to evaluate and quantify this relationship. This route of exposure constitutes a potential infant hazard...Full Text Available

2004-10-01

115

Distribution of lead-203 in human peripheral blood in vitro.  

UK PubMed Central (United Kingdom)

In-vitro experiments using 203Pb were performed to identify the lead binding components in human peripheral blood. The distribution of lead in plasma, in the red cell membrane, and within the red cell...Full Text Available

1980-02-01

116

Effect of lead nitrate on thyroid function on the Indian palm squirrel, Funambulus pennanti (Wroughton)  

Energy Technology Data Exchange (ETDEWEB)

Some of the known toxic effects of lead in mammals including man are, impaired heme synthesis, anemia, nepatopathy, nephropathy, behavioral disorders and neuropathy. However, very little is known about the effect of lead on endocrine physiology. Some data are available on lead induced impairment of thyroid function in occupationally exposed men and experimental rats. As lead nitrate is largely consumed through water and food, in this study the wild rodents Funambulus pennanti were administered lead through their drinking water and their thyroid structure, radioiodine 131-I percentage uptake and protein bound iodine (PBI) level were assessed.

1987-06-01

119

The Effects of Long Term Storage on Special Purpose Lead ...  

Science.gov (United States)

... Special Purpse Lead Azide Lot #I3A-4-62 ... Standard X-ray techniques are not sufficiently sensitive ... the National Bureau of Standards, and examined ...

1972-10-01

120

Lead content of fetal tissues after maternal intoxication  

Energy Technology Data Exchange (ETDEWEB)

A female employee was exposed to lead dust for 8 h daily from 4.5.1982 to 20.5.1982. During this time conception occurred (1st day of last menses 4.5.82). Acute symptoms of lead intoxication were not observed in this subject but were in other employees. Measurements of lead content were started after the end of exposure and continued for 6 months until normal values were obtained. Because of the half-life of nearly 20 days for lead elimination from blood the estimated body burden at the end of exposure was about 1200 ppb. The fetal tissue samples contained between 0.4 (brain) and 7.9 (liver) ..mu..g lead/g dry weight. The fetal lead was mainly stored in bone, blood and liver. From the results given a delayed elimination of fetal lead is suggested.

1986-02-01

121

Investigation of the isotopic composition of lead and of trace elements concentrations in natural uranium materials as a signature in nuclear forensics  

International Nuclear Information System (INIS)

Lead is contained as trace element in uranium ores and propagates throughout the production process to intermediate products like yellow cake or uranium oxide. The lead isotopes in such material originate from two sources: natural lead and radiogenic lead. The variability of the isotopic composition of lead in ores and yellow cakes was studied and the applicability of this parameter for nuclear forensic investigations was investigated. Furthermore, the chemical impurities contained in these materials were measured in order to identify characteristic differences between materials from different mines. For the samples investigated, it could be shown, that the lead isotopic composition varies largely from mine to mine and it may be used as one of the parameters to distinguish between materials of different origins. Some of the chemical impurities show a similar ...

122

Investigation of passive films on nickel Alloy 690 in lead-containing environments  

Energy Technology Data Exchange (ETDEWEB)

Passive films formed on Alloy UNS N06690 were investigated in simulated crevice chemistries. It was found the role of lead in corrosion processes is strongly dependent on the pH value of the testing solutions. At pH 1.5 the effect of lead is narrowly noticeable; while at pH 12.7, lead has a significant influence on the electrochemical performance of alloy UNS N06690. The lead alters the surface morphologies at both pH and account for higher hydroxide content in the surface film at pH 12.7. The lead incorporation hinders the formation of spinel oxides during the passivation in alkaline solution. Nanoindentation tests indicate a significant lead-induced degradation in the mechanical properties of passive films. The passivation degradation is attributed to detrimental effects of lead via interrupting the dehydration process and hindering the ...

2008-09-01

123

Lead and calcium distributions in blood, plasma, and milk of the lactating mouse  

Energy Technology Data Exchange (ETDEWEB)

Although it has been established that lead is transferred in milk from mother to suckling offspring, the physiological processes and parameters involved are not well understood. Single i.v. doses (0.2 mg/kg) or p.o. doses (2 mg/kg) of radiolabeled lead were administered to lactating and nonlactating female mice, and lead concentrations in blood, plasma, and milk were determined during a 21-day period. Large differences in lead elimination were observed between lactating and nonlactation mice. A significant fraction (25%) of the initial maternal dose (absorbed dose) was transferred to the suckling pups. The ratio of lead concentration in milk to lead concentration in plasma was found to be nearly constant over time. However, the milk-to-blood concentration ratios decreased during the same period. Furthermore, the concentration of lead in milk ...

1980-01-01

124

Review of JT-60U experimental results from February to October, 1999  

International Nuclear Information System (INIS)

In 1999, the plasma parameters of reversed shear (RS) plasmas had been extended in 1) DT-equivalent fusion power gain Q_D_T"e"q - 0.5 (n_D(0)#tau#_ET_i(0) - 4x10"2"0 m"-"3#centre dot#keV#centre dot#s) for 0.8 s and 2) full non-inductive current drive with 80% of the bootstrap current fraction. Physics of the internal transport barriers (ITBs) in RS plasmas, including the energy transport and the formation of ITB, were extensively studied. A nearly full current drive (92% non-inductively) was obtained with negative ion based neutral beam (NNB) injection (360 keV, 3.4 MW) in a high #beta#_p H-mode plasma (I_p=1.5 MA, B_T=3.7 T, q_9_5=4.2) with high plasma performance (#beta#_N=2.4 and H_8_9=2.56). Rise in the central electron temperature (T_e - 9 keV) resulted in the current drive efficiency #eta#_C_D of NNB reached 1.3x10"1"9 A/W/m"2, the highest for the neutral beam current drive. As for the H-mode plasmas, decrease in the pedestal ion temperature due to strong gas ...

1994-06-01

125

The loss of lead in biological materials following different drying and ashing procedures  

International Nuclear Information System (INIS)

The loss of lead in various kinds of biological materials after drying and ashing is studied by using "2"0"3Pb as tracer which is intravenously injected into mice. The experimental results show that although the oven ashing can be used for determining the lead in samples of lung, kidney, and liver, etc., the oxygen plasma and high pressure digestion are the most suitable methods for the determination of lead in biological materials. (author) 5 refs.; 2 tabs.

126

Radiochemistry of lead-203 for radiolabelling antibody conjugates  

International Nuclear Information System (INIS)

Lead-203 [52.1 h, 279 (80.1%) KeV] has been recognized as a potentially useful tracer for tumor specific radiopharmaceuticals due to its favorable nuclear and chemical properties. This paper reports the cyclotron production of lead-203 and the labelling of monoclonal antibody B72.3, conjugated with 2-(p-isothiocyanatobenzyl)DOTA, with lead-203 in 30% yield. In vivo biodistribution and stability studies in mice are being conducted.

1990-06-24

127

Evaluation of SO2 Emission Control Technology Applicable to the East Helena Lead Smelter.  

Science.gov (United States)

Contents: Lead smelter operations generating SO2 and particulate; Sulfuric acid plant technology; Lead smelters with sulfuric acid plant SO2 control; Sulfuric acid plant operation with lead sinter machine problems and solutions; SO2 control for ASARCO lea...

1975-01-01

128

Effect of dietary and synthetic chelating agents on the intestinal absorption of lead. [Rats  

Energy Technology Data Exchange (ETDEWEB)

The effect of a number of dietary and synthetic chelating agents on the intestinal absorption of lead has been examined using the everted sac preparation and the tracer isotope /sup 203/Pb. All the agents examined increased lead transport into the serosal compartment. An explanation of the way in which these agents modify the model to describe lead transport is proposed.

1982-01-01

132

Premature Failure of a Riata Defibrillator Lead Without Impedance Change or Inappropriate Sensing: A Case Report and Review of the Literature  

British Library Electronic Table of Contents (United Kingdom)

Premature Failure of a Riata Defibrillator Lead. A 63-year-old woman with a St. Jude Medical Riata 1570 right ventricular lead complained of intermittent hiccups 2 months after implant. Interrogation revealed elevated pacing threshold and diaphragmatic stimulation. Pacing and shock lead impedances remained stable. No inappropriate sensing was noted. Fluoroscopic examination of the lead revealed a thin radio-opaque wire seen between the 2 defibrillator coils away from the main body of the lead. After extraction, a tear in the insulation of the lead was noted allowing the inner wire to protrude. This case illustrates a novel mechanism of insulation failure without inappropriate sensing or impedance change.-(J Cardiovasc Electrophysiol, Vol. 22, pp. 1070-1072, September 2011)

2011-01-01

133

In vivo distribution and excretion studies and in vitro blood studies on the kinetics of lead-203 in beagle dogs  

International Nuclear Information System (INIS)

Studies on the kinetics of the distribution of lead-203 in body fluids have been carried out in vitro, and in animal studies using beagle dogs. In vitro, the distribution of carrier free lead-203 between plasma and cells of canine blood at 37"0C was measured after the addition of isotope. In animal studies, activity in plasma was measured for about 150 hours, and activity in blood cells, urine and feces measured for about 400 hours after exposure to lead-203. Linear compartmental models for distribution of the isotope are presented for both in vitro and in vivo experimental systems. The models contain compartments for both untransformed lead, for isotope added in saline or citric acid, and transformed lead, as obtained by lead-203 incubation in plasma.

134

Pulmonary retention of lead: an experimental study in man  

Energy Technology Data Exchange (ETDEWEB)

This human investigation of lead absorption from the lungs utilized two forms of lead, lead chloride and lead hydroxide; the former was used in picogram amounts and the latter at microgram levels. These two species of lead were selected in an attempt to simulate the range of physicochemical properties found in atmospheric lead (urban air). Aerosols labeled with lead-203 were made of comparable aerodynamic size by using sodium chloride as the deposition-determining aerosol. After brief, mouthpiece exposures, 17 subjects were followed by serial counting with a thoracic array of scintillation detectors and two leg counters. Serial blood samples were also taken. The two exposure groups showed similar total deposition values (23 vs 26%) and the same biological retention halftimes, viz., 22.6 hr. When the retention data were corrected for ...

1980-01-01

135

Effect of calcium and phosphorus on the gastrointestinal absorption of /sup 203/Pb in man  

Energy Technology Data Exchange (ETDEWEB)

Calcium and phosphorus were mainly responsible for reducing the gastrointestinal absorption of lead in human subjects. The effect of calcium was greater than phosphorus, and their combined effect was more than additive. Increasing weights of calcium and phosphorus progressively reduced lead absorption. The relationship between absorption and increasing weights could be described by two negative exponentials. These effects could be explained if lead competed with calcium and phosphorus for common transport mechanisms in the gut. Milk was also found to reduce lead absorption. Adding milk to the diet of people with low dietary calcium intake could reduce the possibility of increased absorption of ingested lead.

1983-02-01

136

Three-step photoionization of mercury for application to separation of mercury isomers  

International Nuclear Information System (INIS)

Development of techniques for separating isomeric nuclides is important to the investigation of schemes for gamma-ray lasers. In preparation for an experiment to separate 10_1_4 atoms of the /sub 197m/Hg (299 keV, tau/sub 1/2/ = 24 hours) isomer, we report isotopically selective resonance ionization of mercury atoms. This has been accomplished by three-step excitation via the 6_3P"1 and 8_1S"0 excited states, using three collinear pulsed laser beams of 254, 286, and 532 nm wavelengths from a Nd:YAG and two dye lasers. These beams were passed through a closed mercury-vapor cell containing electrostatic plates to which the ions were drawn. Ion current and fluorescent radiation were measured as a function of laser frequency. Hyperfine structures for the 254- and 286-nm transitions were observed.

137

The dust distribution in edge-on galaxies. Radiative transfer fits of V and K'-band images  

CERN Document Server

Aims: I have analyzed a sample of seven nearby edge-on galaxies observed in the V and K'-band, in order to infer the properties of the dust distribution. Methods: A radiative transfer model, including scattering, have been used to decompose each image into a stellar disk, a bulge, and a dust disk. The parameters describing the distributions have been obtained through standard X^2 minimization techniques. Results: The dust disks fitted to the V-band images are consistent with previous work in literature: the radial scalelength of dust is larger than that for stars (h_d/h_s ~ 1.5); the dust disk has a smaller vertical scalelength than the stellar (z_d/z_s ~ 1/3); the dust disk is almost transparent when seen face-on (central, face-on, optical depth tau_0 =0.5-1.5). Faster radiative transfer models which neglect scattering can produce equivalent fits, with changes in the derived parameters within the accuracy of full fits including scattering. In the K'-band, no trace ...

2007-01-01

138

The Scientific Publications of Richard H. Dalitz, FRS (1925-2006)  

Energy Technology Data Exchange (ETDEWEB)

Professor Richard H. Dalitz passed away on January 13, 2006. He was almost 81 years old and his outstanding contributions are intimately connected to some of the major breakthroughs of the 20th century in particle and nuclear physics. These outstanding contributions go beyond the Dalitz Plot, Dalitz Pair and CDD poles that bear his name. He pioneered the theoretical study of strange baryon resonances, of baryon spectroscopy in the quark model, and of hypernuclei, to all of which he made lasting contributions. His formulation of the ''{theta} - {tau} puzzle'' led to the discovery that parity is not a symmetry of the weak interactions. A brief scientific evaluation of Dalitz's major contributions to particle and nuclear physics is hereby presented, followed by the first comprehensive list of his scientific publications, as assembled from several sources. The list is divided into two categories: the first, main part ...

2006-03-29

139

Supersymmetric renormalisation group fixed points and third generation fermion mass predictions  

Energy Technology Data Exchange (ETDEWEB)

We present a supersymmetric renormalization group fixed point determination of the third generation fermion masses, in which the large mass ratio between the top and bottom quarks is attributed to a hierarchy in the vacuum expectation values of the two Higgs doublets. Above a supersymmetry breaking scale, M{sub s}, we use the minimal supersymmetric standard model with a transition at M{sub s} to the standard model with only one Higgs- doublet effective. The mass predictions result from renormalization group evolution of large Yukawa couplings at M{sub x} {approximately} 1016 GeV. Averaging over a wide range of these couplings, not subject to any symmetry requirements, gives m{sub t} = 184.3{plus_minus}6.8 GeV, m{sub b} = 4.07{plus_minus}0.33 GeV, m{sub {tau}} = 1.78{plus_minus}0.33 GeV and a light Higgs mass m{sub h}o = 121.8{plus_minus}4.3 GeV for M{sub s} = 1 TeV and {alpha}{sub s} (M{sub z}) = 0.125.

1992-09-01

140

SZ effects from annihilating dark matter in the Milky Way: smooth halo, subhalos and intermediate-mass-black-holes  

CERN Document Server

We study the Sunyaev-Zel'dovich (SZ) effect potentially generated by relativistic electrons injected from dark matter (DM) annihilation or decay in the Galaxy, and check whether it could be observed by Planck or ALMA, or even imprint the current CMB data as e.g. the specific fluctuation excess claimed from an recent re-analysis of the WMAP-5 data. We focus on high-latitude regions to avoid contamination of the Galactic astrophysical electron foreground, and consider the annihilation or decay coming from the smooth DM halo as well as from subhalos, further extending our analysis to a generic modeling of spikes arising around intermediate-mass-black-holes (IMBHs). We show that all these dark Galactic components are unlikely to produce any observable SZ effect. For a self-annihilating DM particle of 10 GeV with canonical properties, the largest optical depth we find is $\\tau_e \\lesssim 10^{-7}$ for massive isolated subhalos hosting IMBHs. We conclude that dark ...

2010-01-01

141

Photoconductive ultraviolet detectors based on ZnO films  

Energy Technology Data Exchange (ETDEWEB)

Properties of photoconductive ultraviolet detectors fabricated on ZnO films were presented. Highly c-axis oriented ZnO films were grown on glass substrates by pulsed laser deposition. Ultraviolet photodetectors were fabricated based on metal-semiconductor-metal planar structures. The photoresponsivity and the quantum efficiency are much higher in the ultraviolet range than in the visible range, and the peak values are around 360 nm. Photocurrent transients show that the detector has a large photocurrent with the peak value of 2.8 mA, and a slow photoresponse with a rise time of 5 min and a decay time of 7 min. The response curve of the detector is fitted well with exponential curve. The large photocurrent should result from the both effects of the accumulation of conduction electrons and the decrease of the barrier height between crystallites. The relaxation time constant {tau} obtained from the curve fitting represents the time accumulation during the process. The ...

2006-12-15

142

Photoconductive ultraviolet detectors based on ZnO films  

International Nuclear Information System (INIS)

Properties of photoconductive ultraviolet detectors fabricated on ZnO films were presented. Highly c-axis oriented ZnO films were grown on glass substrates by pulsed laser deposition. Ultraviolet photodetectors were fabricated based on metal-semiconductor-metal planar structures. The photoresponsivity and the quantum efficiency are much higher in the ultraviolet range than in the visible range, and the peak values are around 360 nm. Photocurrent transients show that the detector has a large photocurrent with the peak value of 2.8 mA, and a slow photoresponse with a rise time of 5 min and a decay time of 7 min. The response curve of the detector is fitted well with exponential curve. The large photocurrent should result from the both effects of the accumulation of conduction electrons and the decrease of the barrier height between crystallites. The relaxation time constant #tau# obtained from the curve fitting represents the time accumulation during the process. The ...

2006-12-15

143

On the evolution of quasicrystalline and crystalline phases in rapidly quenched Al-Co-Cu-Ni alloy  

International Nuclear Information System (INIS)

The occurrence of stable decagonal quasicrystalline phase in Al-Co-Ni and Al-Cu-Co alloys through conventional solidification is well established. Earlier, we have studied the effect of Cu substitution in place of Co in the Al_7_0Co_1_5Ni_1_5 alloy. Here we report the structural/micro-structural changes with substitution of Cu for Ni in rapidly solidified Al-Co-Ni alloys. The melt spun ribbons have been characterized using X-ray diffractometry, scanning and transmission electron microscopy. With an increase in Cu content in the melt spun Al_7_0Co_1_5Cu _xNi_1_5_-_x (x = 0-15 at.%) alloys, the relative amount of the decagonal phase decreased up to 10 at.% of Cu. At this composition, the quaternary alloy showed the co-existence of decagonal quasicrystal and superstructure of #tau#_3 vacancy ordered crystalline phases. The decagonal phase containing Cu showed more disordering than Al-Co-Ni alloys. The implication of the structural and microstructural changes due to Cu ...

2007-03-25

144

Neutrino emission in neutron matter from magnetic moment interactions  

CERN Document Server

Neutrino emission drives neutron star cooling for the first several hundreds of years after its birth. Given the low energy ($\\sim$ keV) nature of this process, one expects very few nonstandard particle physics contributions which could affect this rate. Requiring that any new physics contributions involve light degrees of freedom, one of the likely candidates which can affect the cooling process would be a nonzero magnetic moment for the neutrino. To illustrate, we compute the emission rate for neutrino pair bremsstrahlung in neutron-neutron scattering through photon-neutrino magnetic moment coupling. We also present analogous differential rates for neutrino scattering off nucleons and electrons that determine neutrino opacities in supernovae. Employing current upper bounds from collider experiments on the tau magnetic moment, we find that the neutrino emission rate can exceed the rate through neutral current electroweak interaction by a factor two, signalling ...

2004-01-01

145

Multi-wavelength observations of the young binary system Haro 6-10: The case of misaligned discs  

CERN Document Server

Context. We present a multi-wavelength, high-resolution observational survey of the young binary system Haro 6-10 (GV Tau, IRAS 04263+2426), which is harbouring one of the few known infrared companions. Aims. The primary goal of this project is to determine the physical and geometrical properties of the circumstellar and circumbinary material in the Haro 6-10 system. Methods. High-resolution optical (HST/WFPC2) and near-infrared (VLT/NACO) images in different bands were analysed to investigate the large-scale structures of the material around the binary.Mid-infrared interferometry (VLTI/MIDI) and spectroscopy (TIMMI2 at the 3.6m ESO telescope) were carried out to determine the structure and optical depth of the circumstellar material around the individual components. Results. The multi-wavelength observations suggest that both components of the binary system Haro 6-10 are embedded in a common envelope. The measured extinction indicates a dust composition of the ...

2011-01-01

146

MRI in preoperative evaluation of chronic paranasal sinusitis - a comparison with CT  

International Nuclear Information System (INIS)

Purpose: To determine the value of MRI in the preoperative evaluation of chronic paranasal sinusitis and to compare the results with CT and intraoperative findings. Method/Materials: 42 patients with clinical signs of chronic paranasal sinusitis underwent MRI after CT evaluation on one day, with subsequent functional endoscopic sinus surgery on the next day. Coronary CT was obtained with 5-mm slices and table-feed in the prone position, while MRI was performed in the supine position with coronary T_2-TSE+pd and coronary and transverse HASTE, each with 5-mm slice thickness. Aquisition time in MRI was less than 8 minutes. Two radiologists reviewed the CT and MRI scans for signs of sinusitis and detection of anatomical landmarks. The results were correlated with the intraoperative findings. Results: MRI offered no artifacts of dental work and showed more often high quality pictures than CT. CT and MRI demonstrated a good correlation in the detection of mucosal pathologies ...

2001-04-01

147

Design characteristics of the ion cyclotron system for the KSTAR Tokamak  

Energy Technology Data Exchange (ETDEWEB)

The design of the KSTAR (Korea Superconducting Tokamak Advanced Research) tokamak (R{sub 0} = 1.8 m, a= 0.5 m, {kappa} = 2, {delta} = 1.8 B{sub T} = 3.5 T, I{sub p} 2 MA, {tau}{sub pulse} = 300 s) is being undertaken to do long-pulse. high {beta}, advanced tokamak operating-mode fusion physics experiments. The ion cyclotron (IC) system will deliver 6 MW of rf power to the plasma in the 25 - 60 MHz frequency range, using a single four-strap antenna mounted in a midplane port. It will be used for ion heating, fast-wave current drive (FWCD), and mode conversion current drive (MCCD). The phasing between current straps in the antenna will be adjustable quickly during operation to provide the capability of changing the current-drive efficiency. The IC system will be capable of 300 s operation with 12 MW (upgrade) of rf power to the plasma. (author)

1998-07-01

148

A multi-wavelength scattered light analysis of the dust grain population in the GG Tau circumbinary ring  

Energy Technology Data Exchange (ETDEWEB)

We present the first 3.8 {micro}m image of the dusty ring surrounding the young binary system GG Tau, obtained with the W. M. Keck II 10m telescope's adaptive optics system. THis is the longest wavelength at which the ring has been detected in scattered light so far, allowing a multi-wavelength analysis of the scattering proiperties of the dust grains present in this protoplanetary disk in combination with previous, shorter wavelengths, HST images. We find that the scattering phase function of the dust grains in the disk is only weakly dependent on the wavelength. This is inconsistent with dust models inferred from observations of the interstellar medium or dense molecular clouds. In particular, the strongly forward-throwing scattering phase function observed at 3.8 {micro}m implies a significant increase in the population of large ({approx}> 1 {micro}m) grains, which provides direct evidence for grain growth in the ring. However, the grain size ...

2004-02-04

149

Economic evaluation of an electrolytic process to recover lead from scrap batteries. Information circular/1986  

Energy Technology Data Exchange (ETDEWEB)

The publication is an economic evaluation of the Bureau of Mines electrolytic process for recovering lead from scrap lead-acid batteries. In this process, scrap batteries are crushed and separated into metal and sludge fractions. The metal fraction is cast as anodes and electro-refined. Lead in the sludge fraction is converted to lead carbonate by reaction with an ammonium carbonate-ammonium bisulfite solution. The lead carbonate is then dissolved in a fluosilicic acid electrolyte from which pure lead metal is electrowon. A cost estimate is presented for a plant capable of processing 10,000 scrap batteries per day. The fixed capital cost for the plant is estimated to be $14 million on a fourth quarter 1984 basis. Operating costs are estimated to be $0.15/lb Pb recovered. Assuming a lead selling price of $0.17/lb, the interest rate of return ...

1986-01-01

150

Effect of dose on lead retention and distribution in suckling and adult female mice  

International Nuclear Information System (INIS)

Single doses of lead (trace to 445 mg/kg) were administered per os to suckling and adult mice. Both groups exhibited dose-independent lead retention when doses of 4 to 445 mg/kg were administered. However, developmental differences in the fraction of initial dose (FID) retained were evident for all doses administered. A much larger FID was retained in both age groups following administration of carrier-free "2"0"3Pb. The results are consistent with a mechanism of gastrointestinal lead absorption comprising two or more processes. Developmental differences were also observed in organ lead concentration relative to whole body concentration for kidneys, skull and brain 6 days following lead administration. Lead retentions (relative to whole body retention) in brain and in bone were linearly related to dose of lead administered in both suckling ...

151

Development of Lead-Free Copper Alloy-Graphite Castings  

Energy Technology Data Exchange (ETDEWEB)

In this project, graphite is used as a substitute for lead in order to maintain the machinability of plumbing components at the level of leaded brass. Graphite dispersed in Cu alloy was observed to impart good machinability and reduce the sizes of chips during machining of plumbing components in a manner similar to lead. Copper alloys containing dispersed graphite particles could be successfully cast in several plumbing fixtures which exhibited acceptable corrosion rate, solderability, platability, and pressure tightness. The power consumption for machining of composites was also lower than that of the matrix alloy. In addition, centrifugally cast copper alloy cylinders containing graphite particles were successfully made. These cylinders can therefore be used for bearing applications, as substitutes for lead-containing copper alloys. The results indicate that copper graphite alloys developed under this ...

1999-10-01

152

Cardiac Pacing: Memories of a Bygone Era  

British Library Electronic Table of Contents (United Kingdom)

The first cardiac pacemaker implants occurred in the late 1950s and involved insertion of epicardial or epimyocardial leads and abdominal pulse generators. By the mid 1960s, cardiologists were making attempts to insert transvenous leads into the right ventricle. These early unipolar leads had large, polished, high polarization electrodes, no fixation device, and no lumen in which to place a stylet for lead positioning. The lead implantation procedures were usually long and the irradiation to both patient and operator excessive. Pulse generators were powered by zinc-mercury cells, which were large, unreliable, and prone to sudden output failure. Postoperative complications such as lead dislodgement, exit block, and premature power source failure were very common with most patients requiring...

2008-01-01

153

Absorption of lead from the bronchial region of the lung  

International Nuclear Information System (INIS)

Experiments have been reported previously in which lead-212 ions with lead carrier were instilled into the lungs of anaesthetised rabbits. Experiments were also reported in which bismuth-207 chloride was instilled into rabbit lung. To check that the chloride compound was cleared in the same way as ions instilled in isolation, lead-203 chloride has been instilled in three rabbits. Measurements of absorption of ionic lead have been repeated using the radon-222 daughter, lead-214. Rates of clearance from the lung of "2"0"3Pb as the chloride and "2"1"2Pb ions are compared, and retention functions are derived. Clearance from the lung of "2"1"4Pb ions is also shown, and retention functions are derived. (U.K.).

1978-03-01

154

Radioactive lead studies in the human  

International Nuclear Information System (INIS)

The differing susceptibility of individuals to the toxic effects of chronic lead exposure has never been fully understood. As the major intake of lead in the human is from food and beverages, any variation between individuals of the quantity of lead absorbed from the gut, and of the distribution and excretion of this lead, may account for the differences in individual susceptibility. The food and beverages themselves may have an influence, and to investigate their effects on absorption, distribution and excretion of lead, experiments were performed on normal subjects using a short lived radionuclide of lead, "2"0"3Pb, and instruments generally available in Nuclear Medicine. Lead absorption between different individuals showed a wide variation when "2"0"3Pb was taken as a single dose between meals. Minerals were found to be mainly responsible ...

155

Prediction of response of blood lead to airborne and dietary lead from volunteer experiments with lead isotopes  

Energy Technology Data Exchange (ETDEWEB)

To predict the response of blood lead to airborne and dietary lead requires knowledge of the rate of uptake of lead into the body from lung and gut, its subsequent partitioning between compartments, the stay time in those compartments, and its redistribution or excretion. Tracer studies with volunteers have shown no differences in systemic distribution of inorganic lead between tissues whether it is taken by inhalation, ingestion or injection. Lead is rapidly transferred from plasma to red cells, and there is slower movement thence into liver and other soft tissues, to bone, and to excreta. Work at Harwell and elsewhere with /sup 203/Pb has shown that the initial rapid distribution leaves rather over half the assimilated lead attached to red cells. The result is remarkably consistent, and applies also to dogs and baboons. The renal clearance (Vu) (ratio of U to ...

1985-04-22

156

Pilot study of the relationship of regional road traffic to surface-soil lead levels in Illinois  

Energy Technology Data Exchange (ETDEWEB)

Leaded gasoline has been used as fuel for trucks and automobiles in the United States since 1924; it has been implicated as a source of lead that is deposited on the soil and eventually can be ingested by small children, contributing to their burden of this toxic metal. The lead content of 667 surface-soil samples (taken at depths of 0-5 cm) and 159 subsurface-soil samples (from depths of 25-30 cm) collected from Illinois play areas near roads was measured and related to traffic variables. The samples were collected between June and October of 1985, and their measured lead levels exceeded the average natural background level for Illinois soil. The highest lead concentrations were found in samples from the six-county metropolitan Chicago region, where both traffic volume and traffic density are higher than in the rest of the state. Regression analysis showed significant correlation ...

1987-08-01

157

An Insoluble Titanium-Lead Anode for Sulfate Electrolytes  

Energy Technology Data Exchange (ETDEWEB)

The project is devoted to the development of novel insoluble anodes for copper electrowinning and electrolytic manganese dioxide (EMD) production. The anodes are made of titanium-lead composite material produced by techniques of powder metallurgy, compaction of titanium powder, sintering and subsequent lead infiltration. The titanium-lead anode combines beneficial electrochemical behavior of a lead anode with high mechanical properties and corrosion resistance of a titanium anode. In the titanium-lead anode, the titanium stabilizes the lead, preventing it from spalling, and the lead sheathes the titanium, protecting it from passivation. Interconnections between manufacturing process, structure, composition and properties of the titanium-lead composite material were investigated. The material containing 20-30 vol.% of ...

2005-05-11

158

Sodium bicarbonate-based hydration prevents contrast-induced nephropathy: a meta-analysis  

UK PubMed Central (United Kingdom)

BackgroundContrast-induced nephropathy is the leading cause of in-hospital acute renal failure. This side effect of contrast agents leads to increased morbidity, mortality, and health...Full Text Available

159

Relationships between distribution of lead in erythrocytes in vivo and in vitro and inhibition of ALA-D.  

UK PubMed Central (United Kingdom)

Proteins in the ALA-D (delta-aminolaevulinic acid dehydratase) fraction from gel filtration of erythrocyte supernatant (ES) have the highest affinity for lead among erythrocyte constituents in vivo...Full Text Available

1982-11-01

160

QED processes on e"+e"#+-#-, ep-, #gamma##gamma#-colliders  

International Nuclear Information System (INIS)

The present status of theoretical description of deep-inelastic lepton-nucleon as well as large angle Bhabha scattering with account for radiative corrections in the leading and next-to-leading approximations are reviewed. Also considered is a build-up principle and physical programme of the photon-photon colliders

161

NMDA Receptor Blockade with Memantine Attenuates White Matter Injury in a Rat Model of Periventricular Leukomalacia  

UK PubMed Central (United Kingdom)

Hypoxia–ischemia (H/I) in the premature infant leads to white matter injury termed periventricular leukomalacia (PVL), the leading cause of subsequent neurological deficits. Glutamatergic...Full Text Available

2008-06-25

162

Lyophilized human whole blood for internal and external quality assurance of lead in blood assays  

Energy Technology Data Exchange (ETDEWEB)

Lyophilized human whole blood control material containing lead was prepared for internal and external quality assurance to evaluate and improve the analytical performance of lead. The samples were prepared in four different concentrations from outdated human whole blood stabilized with glucose and a citrate/phosphate buffer and provided under clean room conditions to avoid contamination. The lyophilized samples are easy to reconstitute with water. The materials were evaluated according to a statistical model. The lead concentrations in the specimens are close to blood lead levels usually following environmental and industrial exposure, particular in occupational health to the control of lead exposure at work regulations. The materials are available to the commercial as well as the scientific community. The Danish External Quality Assessment Scheme (DEQAS) for ...

1990-10-01

163

Loss of lysophosphatidylcholine acyltransferase 1 leads to photoreceptor degeneration in rd11 mice  

UK PubMed Central (United Kingdom)

Retinal degenerative diseases, such as retinitis pigmentosa and Leber congenital amaurosis, are a leading cause of untreatable blindness with substantive impact on the quality of life of affected individuals...Full Text Available

2010-08-31

164

Lithium batteries with voltage compatibility with conventional systems  

Science.gov (United States)

The possibility of using lead or lead-bismuth mixed oxides as positive materials in organic electrolyte lithium cells with a working voltage similar to those of conventional systems (1.5 V) has been considered. Performances and main characteristics of this new class of lithium batteries are described.

1980-03-01

165

High affinity of lead for fetal haemoglobin.  

UK PubMed Central (United Kingdom)

In-vitro experiments using 203Pb were performed to identify lead-binding components in human haemoglobin. Sephadex A-50 ion-exchange chromatography of haemolysate showed that different types of haemoglobin...Full Text Available

1980-08-01

166

Cadmium, Lead, and Other Metals in Relation to Semen Quality: Human Evidence for Molybdenum as a Male Reproductive Toxicant  

UK PubMed Central (United Kingdom)

BackgroundEvidence on human semen quality as it relates to exposure to various metals, both essential (e.g., zinc, copper) and nonessential (e.g., cadmium, lead), is inconsistent....Full Text Available

2008-11-01

167

Adaptive Gun Barrel Vibration Absorber.  

Science.gov (United States)

Gun barrel vibrations lead to dispersion in the shot patterns. Thus, reducing these vibrations should lead to increased accuracy. Since the muzzle is the anti-node for all vibration modes and its vibrations have the greatest effect on shot dispersion, it ...

2002-01-01

168

29 CFR 1926.62 - Lead.  

Science.gov (United States)

...retardation, behavioral disorders or...blood. (3) Health protection goals...protecting your health. You are strongly...an independent analysis. The two...impairment of health. One of...although most cases of lead-induced...in the form of behavioral...

2010-07-01

169

Titanate nanotubes as superior adsorbents for removal of lead(II) ions from water  

British Library Electronic Table of Contents (United Kingdom)

Titanate nanotubes were hydrothermally synthesized and their adsorption performances for lead(II) ion removal were studied. The results showed that titanate nanotubes ruptured in the adsorption process resulting in two distinct adsorption stages, thus achieving a maximum adsorption capacity of 3.752mmolg^-^1 of lead(II). Furthermore, it was found that the regeneration of titanate nanotubes loaded with the lead(II) ions can be readily achieved using the saturated EDTA disodium salt aqueous solution, thereby avoiding the trouble of disposal of adsorbent. The adsorption mechanism was also discussed in detail.

2010-01-01

170

Simple method for high-temperature separation of thallium isotopes from a bulk lead target  

Energy Technology Data Exchange (ETDEWEB)

A method is proposed for the quantitative isolation of radiothallium in gas form from proton-bombarded lead of mass up to 20 g. The molten lead is kept at about 800 K in hydrofluoric-acid vapor (HF/H/sub 2/O approx. = 1) at a reduced pressure (less than or equal to4 Pa). We used 99.9% lead with the U-240 cyclotron at the Nuclear Research Institute, Academy of Sciences of the Ukrainian SSR, or the phasotron at the Join Nuclear Research Institute, which gave protons at 65 and 680 MeV correspondingly.

1988-03-01

171

Simple method for high-temperature separation of thallium isotopes from a bulk lead target  

International Nuclear Information System (INIS)

A method is proposed for the quantitative isolation of radiothallium in gas form from proton-bombarded lead of mass up to 20 g. The molten lead is kept at about 800 K in hydrofluoric-acid vapor (HF/H_2O #approx =# 1) at a reduced pressure (#<=#4 Pa). We used 99.9% lead with the U-240 cyclotron at the Nuclear Research Institute, Academy of Sciences of the Ukrainian SSR, or the phasotron at the Join Nuclear Research Institute, which gave protons at 65 and 680 MeV correspondingly.

172

News - News and Events - Nottingham Trent University  

Wastenet

... Lead researcher Dr Preethi Premkumar, who is based in the Division of Psychology at Nottingham Trent University, said: \\

173

Handbook: Approaches for the Remediation of Federal Facility ...  

Science.gov (United States)

... 4-4 UXO disposal operations ... testing of sequencing batch reactor treatment of ... and lead toward the anode compartment ..... ...

1993-09-01

174

Basic Research Leading to Compact, Portable Pulsed Power  

Science.gov (United States)

... 1 ..... 14 High Dielectric Constant Ceramics for Use in Blumlein Transmission Lines ..... 14 ...

2007-03-31

175

A thermal hydraulic investigation on ADSR liquid lead target  

Energy Technology Data Exchange (ETDEWEB)

Computational fluid dynamics(CFD) code FLUENT was used to simulate the thermal hydraulic processes occurring in conceptual design of the accelerator-driven subcritical reactor(ADSR) liquid lead target. The purpose of the analysis is to investigate the thermal hydraulic characteristics of liquid lead as ADSR target material with various target geometries and injection locations of proton beam. In the calculation analysis, the local temperature of the liquid lead target rises to the boiling temperature very rapidly. When the proton beam is injected from the bottom of the target system, the duration time to reach the boiling temperature is longer and the temperature distribution is flatter than other cases.

1998-05-01

177

"2"0"3Pb yields while irradiating thallium with protons and deuterons  

International Nuclear Information System (INIS)

... data deuteron beams energy dependence errors gamma radiation lead 203

178

Production of "2"0"3Pb by proton irradiation of Bi  

International Nuclear Information System (INIS)

Production of lead-203 by proton irradiation of bismuth metal has been investigated as a replacement method for commercially available lead-203. Targets of bismuth metal (0.1 cm thick) were irradiated for periods of 1-3 hours with 90 MeV protons. After processing of the target, the estimated yield of lead-2-3 was 30 millicuries/microamp.

1990-06-24

179

Preparation of radioactive lead complexes utilizing Chelex methodology  

Energy Technology Data Exchange (ETDEWEB)

The use of Chelex resin for the synthesis of radioactive lead complexes has been explored. The process involved immobilization of {sup 203}Pb on the resin and subsequent elution of complexed lead by chelating agents. {sup 203}Pb complexes derived from meso- and racemic dimercaptosuccinic acid (meso-DMSA, rac-DMSA) were prepared and assessed for stability in vitro.

1996-11-01

180

Preparation of radioactive lead complexes utilizing Chelex methodology  

International Nuclear Information System (INIS)

The use of Chelex resin for the synthesis of radioactive lead complexes has been explored. The process involved immobilization of "2"0"3Pb on the resin and subsequent elution of complexed lead by chelating agents. "2"0"3Pb complexes derived from meso- and racemic dimercaptosuccinic acid (meso-DMSA, rac-DMSA) were prepared and assessed for stability in vitro.

1996-11-01

181

Kinetics of lead retention and distribution in suckling and adult rats  

International Nuclear Information System (INIS)

The kinetics of lead distribution was studied in suckling and adult rats 8 days after a single intraperitoneal injection of "2"0"3Pb. Marked differences were observed in the kinetics of lead retention and distribution in suckling as compared to adult rats. The rate of "2"0"3Pb disappearance was lower in the whole body, blood and kidneys, but higher in the liver, while the deposition processes predominated in the brain, femur and teeth of sucklings as compared to adult animals. (auth).

182

In vivo distribution and excretion studies and in vitro blood studies on the kinetics of lead-203 in beagle dogs. [Thesis  

Energy Technology Data Exchange (ETDEWEB)

The distribution of carrier free lead-203 between plasma and cells of canine blood in vitro was measured. Activity in the plasma decreased to less than 5% of the initial blood activity during the first 15 min and then exponentially with a half time of 160 min. Incubation in cell free plasma before addition to whole blood transformed the isotope, decreasing the amount subsequently associated with cells. In animal studies, activity was measured in plasma, blood cells, urine, and feces after exposure to lead-203. In one group, the animals were exposed by intravenous injection of dilute citric acid solutions of isotope. In a second group, carrier free isotope which had been transformed by incubation in plasma was injected intravenously. The kinetics of the distribution of the isotope differed between the two experimental groups. After injection of the transformed lead, the lead-203 content of the blood cell ...

1980-01-01

183

Determination of lead in biological and environmental samples by "2"0"3Pb isotope dilution substoichiometric method  

International Nuclear Information System (INIS)

A procedure for the determination of lead in various biological and environmental samples by "2"0"3Pb radioisotope dilution substoichiometric method is presented. The accuracy of the method by comparison with the literature values of reference materials appears to be good. The standard deviation of the method is less than 10%, and detection limit is about 0.1 #mu#g of lead. (author) 5 refs.

184

Relationship of blood lead to blood pressure in a longitudinal study of working men  

Energy Technology Data Exchange (ETDEWEB)

The relationship of lead exposure to blood pressure has been examined in a longitudinal study of a cohort of 89 Boston, Massachusetts, policemen. At the baseline examination, subjects had a blood lead determination and three consecutive blood pressure measurements. Triplicate blood pressure measurements were also taken at years 3, 4, and 5. Multivariate analysis revealed that, after correction for previous systolic blood pressure, body mass index, age, and smoking, a high level of blood lead was a significant predictor of subsequent elevation of systolic pressure. Bootstrap simulations of these models provided supporting evidence for the observed associations. These data suggest that lead exposure can significantly affect systolic pressure.

1986-05-01

185

Environmental Pollution Levels of Lead and Zinc in Ishiagu and Uburu Communities of Ebonyi State, Nigeria  

British Library Electronic Table of Contents (United Kingdom)

Water and soil samples from the area were therefore analyzed for their lead and zinc content. Computation of pollution statuses of lead and zinc revealed topsoil lead geoaccumulation indices of ?0.143 and ?0.069 and zinc geoaccumulation indices of 1.168 and 0.713 for Ishiagu and Uburu respectively. The pollution indices were determined to be 0.499 and 0.3564 for soil in Ishiagu and Uburu respectively and also 5.11 and 2.42 for water in Ishiagu and Uburu communities respectively. Water/soil concentration ratio were found to be 0.0018 and 0.0014 for lead in Ishiagu and Uburu respectively. On the other hand, the water/soil concentration ratio for zinc was computed to be 0.001 and 0.0008 for Ishiagu and Uburu respectively. These results seem to suggest that the pollution of the environment by ...

2010-01-01

186

Comparative effects of ten dithiocarbamate and thiuram compounds on tissue distribution and excretion of lead in rats  

International Nuclear Information System (INIS)

The dithiocarbamate and thiuram compounds, including disulfiram, were compared for their efficacies in influencing tissue distribution of a trace dose of intravenously injected lead plus "2"0"3Pb in rats. The tested compounds were sodium diethyldithiocarbamate (DEDTC), sodium dimethyldithiocarbamate (DMDTC), tetraethylthiuram disulfide (disulfiram), a complex of zinc and manganese ethylenebisdithiocarbamate (mancozeb), manganese ethylenebisdithiocarbamate (maneb), sodium monomethyldithiocarbamate (metham), zinc propylene bisdithiocarbamate (propineb), tetramethylthiuram disulfide (thiram), zinc ethylenebisdithiocarbamate (zineb), and zinc dimethyldithiocarbamate (ziram). The results of this study show that interactions can occur between lead and DEDTC, DMDTC, disulfiram, metham, thiram, and ziram, resulting in increased levels of lead in brain and probably potentiation of the neurotoxic effects of lead.

187

Biosorption of lead by citrobacter freundii immobilized on hazelnut shells  

Energy Technology Data Exchange (ETDEWEB)

Biosorption of lead from aqueous solutions by living and immobilized cell of C. freundii was examined as a function of metal concentration in a batch laboratory bioreactor. Lead concentrations were analyzed using Atomic Absorption Spectrophotometer (AAS). X-ray Energy Dispersion (EDX) analyses were made in order to determine the accumulation of lead on the cells and shell surfaces. Before and after the experiments the biomaterials and adsorbents were examined by Scanning Electron Microscopy (SEM). Biosorption was detected over a range of initial lead concentrations from 25{times}10{sup -3} to 200{times}10{sup -3} kg/m{sup 3}. 15 refs., 4 figs.

1996-12-31

188

Application of radiolead to metabolic studies  

International Nuclear Information System (INIS)

A review is presented of the literature through 1977 on the uses of radioactive lead isotopes in metabolic studies in man, animals, and plants. These studies have been done mainly with the naturally-occurring, long-lived (22-yr half life) "2"1"0Pb, but a few were with 53-hr "2"0"3Pb or 10.6-hr "2"1"2Pb. Such studies have made possible estimates of the metabolic parameters of lead in man and animals, such as intestinal absorption, the ratio of fecal-to-urinary excretion of endogenous lead, residence time of lead in the body and in various organs, and the distribution in the body (skeleton, liver, kidney, and blood). Subsequently, these parameters and data have been used to trace the sources of lead for man, such as those from the atmosphere, food, cigarette smoke, and automobile exhaust.

189

Toxic effects of lead on neuronal development and function  

Energy Technology Data Exchange (ETDEWEB)

The effects of lead on the development of the nervous system are of immediate concern to human health. While it is clear that lead can affect neuronal development at levels of exposure within the range found in the environment, the particular mechanism of the disruption is not readily ascertained. The goal of the authors research is to develop a model system in which the effects of lead on central nervous system development can be demonstrated. To study neuronal development in a system that minimizes such difficulties, the authors have grafted discrete brain regions derived from rat fetuses into the anterior chamber of the eye of adult hosts. The brain pieces continue organotypic development in the eye, but are isolated from possible secondary changes due to alterations in the development of the endocrine and other somatic systems because the adult host has these systems already fully developed. Using this system, they have ...

1990-11-01

190

Removal of lead from solution using non-living residual brewery yeast  

Energy Technology Data Exchange (ETDEWEB)

A number of preparations of residual non-living brewery yeast were examined for their ability to remove lead from solution. Those preparations included washed and un-washed intact yeast and washed and un-washed homogenates of the yeast cells. Using biosorption isotherm analysis it was found that the washed and un-washed preparations of intact, non-living yeast exhibited maximum biosorption capacities for lead of 127 and 99 mg/g dry weight biomass, respectively. The washed and un-washed cell homogenates exhibited maximum biosorption capacities of 38 and 139 mg lead/g dry weight biomass, respectively. Since it had previously been shown that these preparations of biomass were capable of removing uranium from solution by combined biosorption and precipitation processes, it was decided to examine removal of lead from solution using a form of equilibrium dialysis in which the biomass was retained within a ...

1998-10-01

191

Efficient Inventory Optimization of Multi Product, Multiple Suppliers with Lead Time using PSO  

CERN Document Server

With information revolution, increased globalization and competition, supply chain has become longer and more complicated than ever before. These developments bring supply chain management to the forefront of the managements attention. Inventories are very important in a supply chain. The total investment in inventories is enormous, and the management of inventory is crucial to avoid shortages or delivery delays for the customers and serious drain on a companys financial resources. The supply chain cost increases because of the influence of lead times for supplying the stocks as well as the raw materials. Practically, the lead times will not be same through out all the periods. Maintaining abundant stocks in order to avoid the impact of high lead time increases the holding cost. Similarly, maintaining fewer stocks because of ballpark lead time may lead to shortage of stocks. This ...

2010-01-01

192

Development of highly reliable screening by using x-ray fluorescence spectrometry. Applications to determine lead in tin plated and tin-bismuth plated samples  

International Nuclear Information System (INIS)

A highly reliable screening method was developed for the determination of lead in tin plated layers and tin-bismuth plated layers. The contents of lead in the layers of the various samples were determined by inductively coupled plasma optical emission spectrometry. The calibration curve for lead in the tin and tin-bismuth plated layers by using WD-XRF exhibited linear correlation from 130 #mu#g/g to 2070 #mu#g/g. Calibration curve of lead normalized with Pb-L#alpha#/Sn-K#alpha# intensity was more linear, and this method was possible to evaluate very small sample. The calibration curve for lead in the tin plated layers by using ED-XRF was good linearly, but it for lead in the tin-bismuth plated layers was affected by Pb-L#alpha# spectrum and Bi-L#alpha# spectrum overlap each other. It was effective for decreasing affect of Bi-L#alpha# spectrum by using curve ...

2009-03-01

193

Blood pressure and blood lead concentration in bus drivers  

Energy Technology Data Exchange (ETDEWEB)

San Francisco bus drivers have an increased prevalence of hypertension. This study examined relationships between blood lead concentration and blood pressure in 342 drivers. The analysis reported in this study was limited to subjects not on treatment for hypertension (n = 288). Systolic and diastolic pressure varied from 102 to 173 mm Hg and from 61 to 105 mm Hg, respectively. The blood lead concentration varied from 2 to 15 ..mu..g/dL. The relationship between blood pressure and the logarithm of blood lead concentration was examined using multiple regression analysis. Covariates included age, body mass index, sex, race, and caffeine intake. The largest regression coefficient relating systolic blood pressure and blood lead concentration was 1.8 mm Hg/ln (..mu..g/dL). The coefficient for diastolic blood pressure was 2.5 mm Hg/ln (..mu..g/dL). These findings suggest effects of lead ...

1988-06-01

194

MRI in preoperative evaluation of chronic paranasal sinusitis - a comparison with CT; MRT in der praeoperativen Diagnostik der chronischen Sinusitis im Vergleich mit der CT  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To determine the value of MRI in the preoperative evaluation of chronic paranasal sinusitis and to compare the results with CT and intraoperative findings. Method/Materials: 42 patients with clinical signs of chronic paranasal sinusitis underwent MRI after CT evaluation on one day, with subsequent functional endoscopic sinus surgery on the next day. Coronary CT was obtained with 5-mm slices and table-feed in the prone position, while MRI was performed in the supine position with coronary T{sub 2}-TSE+pd and coronary and transverse HASTE, each with 5-mm slice thickness. Aquisition time in MRI was less than 8 minutes. Two radiologists reviewed the CT and MRI scans for signs of sinusitis and detection of anatomical landmarks. The results were correlated with the intraoperative findings. Results: MRI offered no artifacts of dental work and showed more often high quality pictures than CT. CT and MRI demonstrated a good correlation in the detection of mucosal pathologies ...

2001-04-01

195

Pulmonary retention of lead: an experimental study in man  

Energy Technology Data Exchange (ETDEWEB)

This human investigation of lead absorption from the lungs utilized two forms of lead, lead chloride and lead hydroxide; the former was used in picogram amounts and the latter at microgram levels. These two species of lead were selected in an attempt to simulate the range of physicochemical properties found in atmospheric lead (urban air). Aerosols labeled with lead-203 were made of comparable aerodynamic size (MMAD 0.25 ..mu..m +- 0.1) by using sodium chloride as the deposition-determining aerosol. After brief, mouthpiece exposures, 17 subjects were followed by serial counting with a thoracic array of 12 2-in. scintillation detectors and two 2-in. leg counters, all coupled to single channel analyzers. Serial blood samples were also taken. The two exposure groups showed similar total deposition values (23 vs 26%) and the same biological ...

1980-04-01

196

Placental transfer and fetal distribution of lead in mice after treatment with dithiocarbamates  

Energy Technology Data Exchange (ETDEWEB)

The distribution of i.v. administered lead (/sup 203/Pb-acetate; 50 nmol/kg b.w.) was studied by means of autoradiography and impulse counting in pregnant C57BL mice (day 18) treated orally with dithiocarbamates. Diethyldithiocarbamate (DEDTC), disulfuram or thiram (2 X 1) mmol/kg b.w.) or vehicle (gelatine) alone, was given by gavage 2 h before and immediately after the injection of lead. All three dithiocarbamates, especially thiram, changed the distribution pattern of lead. Thiram and DEDTC had the greatest effect at 4 h after lead administration, disulfiram at 24 h. In the mother, most notably the brain concentration increased (70-fold for thiram at 4 h) while that of erythrocytes and skeleton decreased (50- and 4-fold, respectively). The total fetal concentration unexpectedly showed only a moderate increase (proportional 2-fold for thiram), which may be due partly to the low maternal plasma ...

1984-03-01

197

Placental transfer and fetal distribution of lead in mice after treatment with dithiocarbamates  

International Nuclear Information System (INIS)

The distribution of i.v. administered lead ("2"0"3Pb-acetate; 50 nmol/kg b.w.) was studied by means of autoradiography and impulse counting in pregnant C57BL mice (day 18) treated orally with dithiocarbamates. Diethyldithiocarbamate (DEDTC), disulfuram or thiram (2 X 1) mmol/kg b.w.) or vehicle (gelatine) alone, was given by gavage 2 h before and immediately after the injection of lead. All three dithiocarbamates, especially thiram, changed the distribution pattern of lead. Thiram and DEDTC had the greatest effect at 4 h after lead administration, disulfiram at 24 h. In the mother, most notably the brain concentration increased (70-fold for thiram at 4 h) while that of erythrocytes and skeleton decreased (50- and 4-fold, respectively). The total fetal concentration unexpectedly showed only a moderate increase (proportional 2-fold for thiram), which may be due partly to the low maternal plasma ...

198

Dose dependent transfer of [sup 203]lead to milk and tissue uptake in suckling offspring studied in rats and mice  

Energy Technology Data Exchange (ETDEWEB)

The dose-dependent transfer of [sup 203]Pb to milk and uptake in suckling rats and mice during a three-day nursing period was studied. On day 14 of lactation, the dams were administered a single intravenous dose of lead, labelled with [sup 203]Pb, in four or five doses from 0.0005 to 2.0 mg Pb/kg b.wt. There was a linear relationship between Pb levels in plasma and milk of both species. The Pb milk: plasma ratios at 24 hr after administration were 119 and 89 in mice and rats, respectively. At 72 hr the Pb milk: plasma ratio had decreased to 72 in mice and 35 in rats. The tissue levels of lead in the suckling rats and mice were also linearly correlated with lead concentration in milk at 72 hr, showing that milk could be used as an indicator of lead exposure to the suckling offspring. It is concluded that lead is transported into rat and mouse milk to a very high extent and the ...

1993-09-01

199

Distribution of lead-203 in human peripheral blood in vitro  

International Nuclear Information System (INIS)

In-vitro experiments using "2"0"3Pb were performed to identify the lead binding components in human peripheral blood. The distribution of lead in plasma, in the red cell membrane, and within the red cell was also investigated. Studies of the distribution of "2"0"3Pb in the whole blood showed that at a lead concentration of 2.45 #mu#mol/l (50 #mu#g/100 ml) about 94% of lead had been incorporated by the erythrocytes and 6% remained in the plasma. After extraction of lipid by a methanol/chloroform mixture, about 75% of the lead was found to be associated with the protein fraction. The lipid contained about 21% of the "2"0"3Pb, the remainder being in the aqueous plasma. SDS polyacrylamide gel electrophoresis of blood plasma showed that almost 90% of the "2"0"3Pb was present in the albumin fraction; the remainder was likely to be associated with high molecular weight globulins. Several ...

200

The IceCube Collaboration:contributions to the 30 th International Cosmic Ray Conference (ICRC 2007),  

Energy Technology Data Exchange (ETDEWEB)

This paper bundles 40 contributions by the IceCube collaboration that were submitted to the 30th International Cosmic Ray Conference ICRC 2007. The articles cover studies on cosmic rays and atmospheric neutrinos, searches for non-localized, extraterrestrial {nu}{sub e}, {nu}{sub {mu}} and {nu}{sub {tau}} signals, scans for steady and intermittent neutrino point sources, searches for dark matter candidates, magnetic monopoles and other exotic particles, improvements in analysis techniques, as well as future detector extensions. The IceCube observatory will be finalized in 2011 to form a cubic-kilometer ice-Cherenkov detector at the location of the geographic South Pole. At the present state of construction, IceCube consists of 52 paired IceTop surface tanks and 22 IceCube strings with a total of 1426 Digital Optical Modules deployed at depths up to 2350 m. The observatory also integrates the 19 string AMANDA subdetector, that was completed in 2000 and extends ...

2007-11-02

201

Plasma neutralization models for intense ion beam transport in plasma  

Energy Technology Data Exchange (ETDEWEB)

Plasma neutralization of an intense ion pulse is of interest for many applications, including plasma lenses, heavy ion fusion, cosmic ray propagation, etc. An analytical electron fluid model has been developed based on the assumption of long charge bunches (l{sub b} >> r{sub b}). Theoretical predictions are compared with the results of calculations utilizing a particle-in-cell (PIC) code. The cold electron fluid results agree well with the PIC simulations for ion beam propagation through a background plasma. The analytical predictions for the degree of ion beam charge and current neutralization also agree well with the results of the numerical simulations. The model predicts very good charge neutralization (>99%) during quasi-steady-state propagation, provided the beam pulse duration {tau}{sub b} is much longer than the electron plasma period 2{pi}/{omega}{sub p}, where {omega}{sub p} = (4{pi}e{sup 2}n{sub p}/m){sup 1/2} is the electron plasma ...

2003-05-01

202

Infinite Dimensional Groups and Riemann Surface Field Theories  

International Nuclear Information System (INIS)

We show how to obtain positive energy representations of the group G of smooth maps from a union of circles to U(N) from geometric data associated with a Riemann surface having these circles as boundary. Using covering spaces we can reduce to the case where N=1. Then our main result shows that Mackey induction may be applied and yields representations of the connected component of the identity of G which have the form of a Fock representation of an infinite dimensional Heisenberg group tensored with a finite dimensional representation of a subgroup isomorphic to the first cohomology group of the surface obtained by capping the boundary circles with discs. We give geometric sufficient conditions for the correlation functions to be positive definite and derive explicit formulae for them and for the vacuum (or cyclic) vector. (This gives a geometric construction of correlation functions which had been obtained earlier using tau functions.) By choosing particular ...

1996-01-01

203

FORMATION EPOCHS, STAR FORMATION HISTORIES, AND SIZES OF MASSIVE EARLY-TYPE GALAXIES IN CLUSTER AND FIELD ENVIRONMENTS AT z = 1.2: INSIGHTS FROM THE REST-FRAME ULTRAVIOLET  

International Nuclear Information System (INIS)

We derive stellar masses, ages, and star formation histories (SFHs) of massive early-type galaxies in the z = 1.237 RDCS1252.9-2927 cluster and compare them with those measured in a similarly mass-selected sample of field contemporaries drawn from the Great Observatories Origin Deep Survey South Field. Robust estimates of these parameters are obtained by comparing a large grid of composite stellar population models with 8-9 band photometry in the rest-frame near-ultraviolet, optical, and IR, thus sampling the entire relevant domain of emission of the different stellar populations. Additionally, we present new, deep U-band photometry of both fields, giving access to the critical far-ultraviolet rest frame, in order to empirically constrain the dependence of the most recent star formation processes on the environment. We also analyze the morphological properties of both samples to examine the dependence of their scaling relations on their mass and environment. We find that early-type ...

2010-01-20

204

Comparison of radiationless decay processes in osmium and platinum porphyrins  

International Nuclear Information System (INIS)

Two osmium porphyrin complexes, Os(OEP)L_2 [OEP = octaethylporphin, L = py(pyridine) or NO], and PtOEP were investigated by picosecond laser spectroscopy with use of a double-beam, mode-locked Nd:glass system delivering 6-ps (fwhm) pulses at 527 nm with 1-2mJ/pulse. Time-resolved excited-state spectra were recorded from the time of photoexcitation to 5 ns after photoexcitation. The initial excited state, S_1, decayed in less than or equal to9 ps for the two osmium complexes and in less than or equal to15 ps for the platinum porphyrin. A second excited state, T_1, lived for 1, 9, and >50 ns respectively for Os(OEP)(py)_2, Os(OEP)(NO)_2, and PtOEP. The #DELTA#A spectra of the T_1 states of the osmium complexes were similar to those of previously reported (d/sub #pi#/,#pi#*) states for Os(OEP)(py)_2 and (#pi#,#pi#*) states for Os(OEP)(NO)_2. This finding supports prior assignments of these states on the basis of expected axial and equatorial back-bonding of the osmium's d electrons. ...

205

Bone marrow MR imaging as predictors of outcome in hemopoietic stem cell transplantation  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study is to investigate the role of femoral marrow MR imaging as predictor of outcome for hemopoietic stem cell transplantation (HSCT) in beta-thalassemia major. MR imaging of the proximal femur, including T1- and T2-weighted spin echo and short-tau inversion recovery and in-phase and out-of-phase fast field echo images, was prospectively performed in 27 thalassemia major patients being prepared for HSCT. The area of red marrow and its percentage of the proximal femur were measured, and the presence of marrow hemosiderosis was assessed. Age-adjusted multivariate logistic regression was used to determine the relationship between red marrow area percentage and marrow hemosiderosis and HSCT outcome. Red area percentage were less in patients with successful (90.25{+-}4.14%) compared to unsuccessful transplants (94.54% {+-}2.93%; p=0.01). Red marrow area percentage correlated positively with duration of symptoms(r=0.428, p=0.026) and serum ferritin ...

2008-09-15

206

The effect of flow-hole structure and water chemistry on scale adhesion at the leading edge of a flow hole in a heat exchanger  

International Nuclear Information System (INIS)

In the heat exchangers of power plants, scale deposition may occur, especially at the leading edge of contraction. The growth of scale can lead to an increase in pressure and cause oscillation of the water level. In our previous study, the dependence of flow on contraction geometry was analyzed numerically and empirically. It was shown that the contraction ratio of hydraulic diameter of the flow path contributed greatly to the difference in pressure drop and turbulent kinetic energy at the leading edge of the flow path. In this study, the effect of contraction geometry and flow rate on scale adhesion was studied in AVT chemistry at 270degC using a high-velocity scale-adhesion test loop. The differential pressure and the amount of scale deposited due to scale adhesion at the leading edge of the flow path increased more in a quatrefoil-type flow path than in drill-type flow path. The differential pressure ...

1999-05-01

207

Radiotracer study of lead adsorption on glass from very dilute aqueous solutions  

Energy Technology Data Exchange (ETDEWEB)

This study deals with the adsorption and desorption of lead (c <= 10/sup -8/ - 10/sup -3/ M), labelled with /sup 212/Pb or /sup 210/Pb, on glass in relation to pH and composition of the solution, concentration of lead and time. The prevailing mechanism of the adsorption in the pH range from 3 to 8 is the ion exchange of Pb/sup 2 +/ and PbOH/sup +/ ions in electric double layer on the surface of glass. At the higher pH values lead (c <= 10/sup -8/ - 10/sup -6/ M) is adsorbed mainly by physical adsorption or chemisorption of its hydrolyzed forms. A rather high adsorption capacity of glass, exceeding 3.10/sup -9/ M/cm/sup 2/, has been found in neutral solutions for the cationic forms of lead. The adsorbed lead can be easily desorbed with the solution of 1 M nitric acid.

1981-01-01

208

Proper Assessment of the JFK Assassination Bullet Lead Evidence from Metallurgical and Statistical Perspectives  

Energy Technology Data Exchange (ETDEWEB)

The bullet evidence in the JFK assassination investigation was reexamined from metallurgical and statistical standpoints. The questioned specimens are comprised of soft lead, possibly from full-metal-jacketed Mannlicher-Carcano, 6.5-mm ammunition. During lead refining, contaminant elements are removed to specified levels for a desired alloy or composition. Microsegregation of trace and minor elements during lead casting and processing can account for the experimental variabilities measured in various evidentiary and comparison samples by laboratory analysts. Thus, elevated concentrations of antimony and copper at crystallographic grain boundaries, the widely varying sizes of grains in Mannlicher-Carcano bullet lead, and the 5-60 mg bullet samples analyzed for assassination intelligence effectively resulted in operational sampling error for the analyses. This deficiency was not considered in the original ...

2006-08-29

209

Lead exposure via drinking water - unnecessary and avoidable; Bleiexposition ueber das Trinkwasser - unnoetig und vermeidbar  

Energy Technology Data Exchange (ETDEWEB)

Despite successful reduction of the general lead exposure, this heavy metal is still a matter of public concern due to the fact that associations with intellectual impairment or delayed puberty are found to correlate with very low lead blood concentrations. Lead in tap water is still an important contribution to lead exposure which may cause health risk for infants. Therefore, lead pipes should be completely sanitated by exchange against pipes made from more healthy materials. (orig.) [German] Trotz erfolgreicher Reduktion der allgemeinen Belastung ist Blei auch heute noch umweltmedizinisch relevant, weil es moeglicherweise bei niedrigeren als bisher angenommenen Belastungen gesundheitlich nachteilige Wirkungen, insbesondere waehrend der fruehkindlichen Entwicklung des Nervensystems, ausloest. Insbesondere Blei aus bleiernen Trinkwasserleitungen ist eine Belastung, die fuer ...

2003-07-01

210

Bioavailability of lead in rats fed human diets  

International Nuclear Information System (INIS)

The bioavailability of lead was studied in rats fed various baby foods (Babymix-turkey, Babymix-vegetables, Frutolino-fruit, Frutamix-bananas, Babyron-S-26, Truefood), cow's milk, bread, liver and standard rat diet. Lead absorption was determined by measuring the whole body retention of "2"0"3Pb 6 days after a single oral application. Highest absorption values ranging from 17 to 20% were obtained in animals fed cow's milk and fruit foods. Rats on other human diets absorbed between 3 and 8% of the radioactive lead dose. Only in animals on rat diet lead absorption was below 1%. It is concluded that rats fed human diets show absorption values similar to those in humans. This might indicate that the bioavailability of lead is primarily dependent on dietary habits. This experimental model, if confirmed by further work, might be useful for obtaining preliminary data on the bioavailability ...

211

The use of lead isotopic abundances in trace uranium samples for nuclear forensics analysis  

International Nuclear Information System (INIS)

Secondary ion mass spectrometry (SIMS), secondary electron microscopy (SEM) and X-ray analysis have been applied to the measurement of U-bearing particles with the intent of gleaning information concerning their history and/or origin. The lead isotopic abundances are definitive indicators that U-bearing particles have come from an ore-body, even if they have undergone chemical processing. SEM images and X-ray analysis can add further information to the study that may allude to the extent of chemical processing. The presence of 'common' lead that does not exhibit a radiogenic signature is clear evidence of anthropogenic origin. (author)

2010-06-01

212

Recovery of radioactive thallium isotopes from lead and bismuth targets irradiated by 1-GeV protons  

Energy Technology Data Exchange (ETDEWEB)

A simple highly efficient procedure has been developed for recovery of thallium radioisotopes from lead and bismuth targets irradiated by 1-GeV protons. The procedure is based on the use of extraction chromatography. The cross-sections have been determined for formation of {sup 200}Pb, {sup 201}Pb, {sup 202m}Pb, and {sup 203}Pb radioisotopes in targets from lead with natural isotopic composition, irradiated by 1-GeV protons.

1995-03-01

213

Recovery of radioactive thallium isotopes from lead and bismuth targets irradiated by 1-GeV protons  

International Nuclear Information System (INIS)

A simple highly efficient procedure has been developed for recovery of thallium radioisotopes from lead and bismuth targets irradiated by 1-GeV protons. The procedure is based on the use of extraction chromatography. The cross-sections have been determined for formation of "2"0"0Pb, "2"0"1Pb, "2"0"2"mPb, and "2"0"3Pb radioisotopes in targets from lead with natural isotopic composition, irradiated by 1-GeV protons.

214

Lead oxides-lithium cells  

Science.gov (United States)

The possibility of using lead and lead-bismuth mixed oxides as positive active materials in organic electrolyte lithium cells with a working voltage similar to those of silver zinc cells has been considered. Button cells of SR 44 size have been developed as a test vehicle and studied under various conditions of discharge rate and storage. This paper describes the performance characteristics obtained under these conditions and suggests in conclusion the possible replacement of silver zinc cells by such systems for a large range of low-rate applications on the basis of cost effectiveness.

1979-01-01

215

Influence of dietary amino acids on lead absorption  

International Nuclear Information System (INIS)

Dietary supplements of about 5 g/kg of a number of amino acids increased tissue lead concentrations in newly weaned rats but decreased them in older rats. The retention of both oral and intraperitoneal lead was affected. The uptake of "2"0"3Pb by tissues was reduced when methionine was given in the diet over a period of 5 weeks or when it or ethionine was given by mouth 24 h before the activity was measured. In the liver the fraction of the total activity found in the nuclei and mitochondria was increased by methionine, but in the kidney only the fraction found in nuclei was increased.

216

Gastrointestinal absorption of lead-203 chloride in man  

International Nuclear Information System (INIS)

Studies of the gastrointestinal absorption of lead-203 chloride were carried out on 11 normal subjects, 7 males and 4 females. Whole body counting of these subjects after administration of 74 kBq (2 #mu#Ci) of cyclotron-produced lead-203 chloride showed a mean absorption of 21.3% of the dose with a range from 10.4 to 47.7%. The male subjects had a lower mean absorption of 18.1% of the dose compared with a mean of 26.9% in the females. Although this difference did not reach statistical significance, it is postulated that male/female differences in absorption may relate to differences in iron saturation of the subjects.

217

From recreational mathematics to recreational programming, and back  

British Library Electronic Table of Contents (United Kingdom)

Recreational Programming (RecPro) is the discipline that encourages the study of computer programming through ludic problems. Problems that are typically studied within this discipline are similar to those of Recreational Mathematics (RecMat), which sometimes leads to the confusion of these two disciplines. The objective for RecPro is to write programs, while RecMat practitioners can use these programs to state (and prove if possible) conjectures about the solution. This interaction leads to a mathematical quality production. In an educational framework, problems in elemental number theory (those that are formulated with a basic knowledge of arithmetic) are very interesting, leading to the revision of classical unsolved problems. One of these problems is the general form of Zumkeller numbe...

2011-01-01

218

Biosorption process for removing heavy metal ions using water milfoil (Myriophyllum Spicatum) in contaminated water  

Energy Technology Data Exchange (ETDEWEB)

A small scale biomass metal contacting experiment was performed to screen the optimal plant species for biosorption and bioaccumulation of cadmium, zinc, nickel, lead, and copper. Experiments were also conducted to test the ability of the biomass to lower the metal concentrations below the US Environmental Protection Agency surface water discharge criteria. The minimum residual concentration was 0.1 mg/L for zinc, 0.004 mg/L for lead, and about 0.01 mg/L for cadmium, nickel, and lead. Results indicate that water milfoil can be used for bioremoval of metals.

1995-12-31

219

Thermoluminescence studies in lead doped KCl and KBr crystals  

International Nuclear Information System (INIS)

Lead is known to enter substitutionally in divalent state when doped in alkali halides. When irradiated at room temperature these lead centers (Pb"+"+) act as traps for electrons knocked off from the halogen ions and become Pb"+ and Pb"0 (for large doses of irradiation). These changes could be followed in the optical absorption studies. These lead-doped crystals after X-ray irradiation yield a thermoluminescence output smaller than that observed in 'pure' crystals. However, two new glow peaks are observed in additions to those due to F-centers. In KCl : Pb and Kbr : Pb crystals part of the F-center glow preceds the new glow peaks. The new peaks are attributed to the Pb"+ and Pb"0 centers. The glow peak temperatures and trap depths for these peaks an obtained by total-curve fitting method are reported. (author).

1975-02-12

220

The IKK complex contributes to the induction of autophagy  

UK PubMed Central (United Kingdom)

In response to stress, cells start transcriptional and transcription-independent programs that can lead to adaptation or death. Here, we show that multiple inducers of autophagy, including nutrient...Full Text Available

2010-02-03

221

The Heart Failure Epidemic  

UK PubMed Central (United Kingdom)

Heart failure has been singled out as an emerging epidemic, which could be the result of increased incidence and/or increased survival leading to increased prevalence. Knowledge of the responsibility...Full Text Available

2010-04-01

222

The Epidemiology of Cosmetic Treatments for Corneal Opacities in a Korean Population  

UK PubMed Central (United Kingdom)

PurposeTo describe etiologies and clinical characteristics of corneal opacities leading patients to seek cosmetic treatments.MethodsThe medical records...Full Text Available

2010-06-01

223

Tachyons and the causal paradox  

International Nuclear Information System (INIS)

The author attempts to clear up the causal 'paradox' often associated with the existence of tacyons. This leads to a discussion of the nature of tachyon messages and the problems involved in their interpretation. (W.D.L.).

224

Structure and function of an acetylcholine receptor.  

UK PubMed Central (United Kingdom)

Structural analysis of an acetylcholine receptor from Torpedo californica leads to a three-dimensional model in which a "monomeric" receptor is shown to contain subunits arranged around a central ionophoretic...Full Text Available

1982-01-01

225

Streamlining lead discovery by aligning in silico and high-throughput screening  

British Library Electronic Table of Contents (United Kingdom)

Lead discovery in the pharmaceutical environment is largely an industrial-scale process in which it is typical to screen 1-5 million compounds in a matter of weeks using High Throughput Screening (HTS). This process is a very costly endeavor. Typically a HTS campaign of 1 million compounds will cost anywhere from $500000 to $1000000. There is consequently a great deal of pressure to maximize the return on investment by finding fast and more effective ways to screen. A panacea that has emerged over the past few years to help address this issue is in silico screening. In silico screening is now incorporated in all areas of lead discovery; from target identification and library design, to hit analysis and compound profiling. However, as lead discovery has evolved over the past few years, so h...

2006-01-01

226

Stochastic gene expression and its consequences  

UK PubMed Central (United Kingdom)

Gene expression is a fundamentally stochastic process, with randomness in transcription and translation leading to significant cell-to-cell variations in mRNA and protein levels. This variation...Full Text Available

2008-10-17

227

Separation of lead-203 from cyclotron-bombarded thallium targets by ion-exchange chromatography  

Energy Technology Data Exchange (ETDEWEB)

A simple method is presented for the separation of lead-203 from copper-backed thallium cyclotron targets. The procedure involves cation-exchange chromatography in hydrochloric acid and hydrochloric acid-acetone mixtures. Further purification involves anion-exchange chromatography in nitric acid-hydrobromic acid mixtures. A cation-exchange column containing 3.0 g of resin can handle as much as 15 g of thallium and 160 mg of copper. An anion-exchange column containing 3.0 g of resin can separate lead from up to 200 mg of thallium and 10 mg of copper. Separations are extremely sharp and less than 0.1 ..mu..g of thallium and less than 0.1 ..mu..g of copper remain in the lead-203 fraction.

1982-07-01

228

Separation of lead-203 from cyclotron-bombarded thallium targets by ion-exchange chromatography  

International Nuclear Information System (INIS)

A simple method is presented for the separation of lead-203 from copper-backed thallium cyclotron targets. The procedure involves cation-exchange chromatography in hydrochloric acid and hydrochloric acid-acetone mixtures. Further purification involves anion-exchange chromatography in nitric acid-hydrobromic acid mixtures. A cation-exchange column containing 3.0 g of resin can handle as much as 15 g of thallium and 160 mg of copper. An anion-exchange column containing 3.0 g of resin can separate lead from up to 200 mg of thallium and 10 mg of copper. Separations are extremely sharp and less than 0.1 #mu#g of thallium and less than 0.1 #mu#g of copper remain in the lead-203 fraction. (author).

229

Science@Berkeley Lab Magazine  

Science.gov (United States)

will soon recreate by slamming lead nuclei into one another. S@BL image Irrelevant Regulators Pinpointing the interactions of genes with their assumed regulators grows ever more...

2011-08-19

230

Review of Cost-Effectiveness Analysis of Medical Treatment For Myocardial Infarction  

UK PubMed Central (United Kingdom)

Objectives:Myocardial infarction (MI) is a leading cause of death in both the industrialized and developing countries globally. The economic evaluation of MI is undertaken...Full Text Available

2011-04-01

231

Redistribution and increased brain uptake of lead in rats after treatment with diethyldithiocarbamate  

International Nuclear Information System (INIS)

Diethyldithiocarbamate (DDTC), a chelating agent, is an active metabolite of disulfiram (Antabus) and is used in the rubber industry. The effect of DDTC on the tissue distribution of "2"0"3Pb was studied in rats. Two groups of rats were given an i.v. injection of 100 #mu#Ci "2"0"3Pb (28.6 nmol/kg b.wt.) as lead acetate. After 10 min one group received 2 mmol/kg b.wt. of DDTC as an i.p. injection. Rats were killed 4 and 72 h after injection of "2"0"3Pb and tissue concentration and excretion of "2"0"3Pb was determined by gamma counting. The brain concentration of "2"0"3Pb in DDTC-treated rats was nine times higher than in controls after 4 h and 14 times higher after 72 h. Treatment with DDTC also increased the lead concentration in fat about seven times at both survival intervals. On the other hand, uptake of "2"0"3Pb in bone was reduced by treatment with DDTC and at 4 h also kidney and blood had a lower concentration of "2"0"3Pb in DDTC-treated ...

232

RESEARCH ON FLOW SEPARATION IN WESTERN EUROPE  

Science.gov (United States)

... Separation," AGARD,Rept 272, April 1960, ... Leading Edge Effect on Supersonic Boundary Layer Flow." ... of Gas Injection in Separated Flows." TCEA, ...

1963-07-01

233

PET imaging of tumour hypoxia  

UK PubMed Central (United Kingdom)

Tumour hypoxia represents a significant challenge to the curability of human tumours leading to treatment resistance and enhanced tumour progression. Tumour hypoxia can be detected by non-invasive and...Full Text Available

234

Oxidative Stress Disrupts Oligodendrocyte Maturation  

UK PubMed Central (United Kingdom)

Periventricular white matter injury (PWMI), is the leading cause of chronic neurologic injury among survivors of preterm birth. The hallmark of PWMI is hypomyelination and a lack of mature,...Full Text Available

2009-11-01

235

Nuclear medicine and imaging research. Progress report, January 1, 1980-December 31, 1980. [Lead Abstract  

Energy Technology Data Exchange (ETDEWEB)

Separate abstracts were prepared for the 5 subprojects designated as projects 1 to 4 and 6 in this progress report. (KRM)

1980-09-01

236

New frontiers in competition for pollination  

UK PubMed Central (United Kingdom)

BackgroundCo-flowering plant species frequently share pollinators. Pollinator sharing is often detrimental to one or more of these species, leading to competition for pollination....Full Text Available

2009-06-01

237

Neonatal Sepsis and Neutrophil Insufficiencies  

UK PubMed Central (United Kingdom)

Sepsis has continuously been a leading cause of neonatal morbidity and mortality despite current advances in chemotherapy and patient intensive care facilities. Neonates are at high risk for...Full Text Available

2010-06-01

238

NASA's Next Major Space Observatory - Flight Projects - NASA  

Science.gov (United States)

of Earth Science data and information management capabilities. Dale Schulz/400 . For your exceptional achievement in leading the joint LaRC/GSFC team in ...

239

Molecular mechanisms of the epithelial transport of toxic metal ions, particularly mercury, cadmium, lead, arsenic, zinc, and copper. Progress report, January 1, 1979-December 31, 1979  

International Nuclear Information System (INIS)

The mechanism of lead transport is presented, and especially the particular similarities or dissimilarities between lead and calcium in this process. The absorption of these metals was determined cockerels, raised on a commercial diet or on a specified diet, using in vivo ligated loop procedure. The dose administered into the loop contained 0.5 #mu#Ci "2"0"3Pb (and/or 0.1 #mu#Ci "4"7Ca), and 0.01 mM lead acetate (and/or mM CaCl_2) in 0.5 ml 0.15 M NaCl,pH 6.5. It was shown that lead is rapidly taken up by the mucosal tissue, and slowly transferred into the body, whereas less calcium is retained by the tissue and the transfer of calcium is many times as effective as that for lead. They appear to respond in a similar manner to a low calcium intake and vitamin D treatment. Increasing luminal stable lead concentration significantly reduced the percentage of ...

240

Misfolded Proteins and Retinal Dystrophies  

UK PubMed Central (United Kingdom)

Many mutations associated with retinal degeneration lead to the production of misfolded proteins by cells of the retina. Emerging evidence suggests that these abnormal proteins cause cell death...Full Text Available

2010-01-01

241

Microsoft Word - PressRelease Marine fuel 150711final21.doc  

Wastenet

be extremely limited or even negative due to higher maritime transport costs leading to a modal shift back to

242

Metals and kidney autoimmunity.  

UK PubMed Central (United Kingdom)

The causes of autoimmune responses leading to human kidney pathology remain unknown. However, environmental agents such as microorganisms and/or xenobiotics are good candidates for that role. Metals,...Full Text Available

1999-10-01

243

Mechanism of viscosity effect on magnetic island rotation  

Energy Technology Data Exchange (ETDEWEB)

It is shown that plasma viscosity does not influence the magnetic island rotation directly. Nevertheless, it leads to nonstationarity of the plasma velocity. This nonstationarity is the reason of the viscosity effect on island rotation. (author)

2000-04-01

244

MST Division Work for Others  

Science.gov (United States)

[[pdf] Reference Guide for Proposals 07/09 [pdf] FY11 Overhead Rate Calculator (xls) DARPA Opportunities NIH Proposals (Leads & Subcontractors) [NIH Office] Related Links MST...

2011-08-27

245

Loss of cell components during rehydration of dried Rhodotorula glutinis and its implications for lead uptake  

British Library Electronic Table of Contents (United Kingdom)

Abstract Microbial cells are routinely dried and ground before they are used in metal biosorption studies. In this work, a metal biosorbent was prepared by drying biomass of the yeast Rhodotorula glutinis in an oven at 70C for 24-h followed by grinding. Two forms of the prepared biosorbent particles, washed and unwashed, were examined for their ability to remove lead from solution. It was found that the unwashed biosorbent exhibited higher lead uptake than the washed biosorbent. Analysis of the supernatant of washed cells incubated in water and that of unwashed cells incubated in lead solution revealed the presence of protein, carbohydrates, organic acids and inorganic phosphate. Overall, the washed and unwashed cells leached, respectively, 14.5 and 13.4% of their initial dry weight (100-m...

2011-01-01

246

Lead, copper and zinc biosorption from bicomponent systems modelled by empirical Freundlich isotherm  

Energy Technology Data Exchange (ETDEWEB)

The biosorption of lead, copper and zinc ions on Rhizopus arrhizus has been studied for three single-component and two binary systems. The equilibrium data have been analysed using the Freundlich adsorption model. The characteristic parameters for the Freundlich adsorption model have been determined and the competition coefficients for the competitive biosorption of Pb(II)-Cu(II) at pH 4.0 and 5.0, and Pb(II)-Zn(II) at pH 5.0 have been calcualted. For the individual single-component isotherms, lead has the highest biosorption capacity followed by copper, then zinc. The capacity of lead in the two binary systems is always significantly greater than those of the other metal ions, in agreement with the single-component data. Only a partial selectivity for copper ions has been obtained at pH 4.0. (orig.)

2000-07-01

247

Ion channels, transporters, and pumps as targets for heart failure  

UK PubMed Central (United Kingdom)

Congestive heart failure (CHF) is a leading cause of morbidity and mortality. CHF is marked by atrial and ventricular enlargement and reduced cardiac contractility, as well as an association...Full Text Available

2009-10-01

248

In vivo MRI analysis of an inflammatory injury in the developing brain  

UK PubMed Central (United Kingdom)

Cerebral periventricular white matter injury stands as a leading cause of cognitive, behavioral and motor impairment in preterm infants. There is epidemiological and histopathological evidence...Full Text Available

2010-07-01

249

Immunomodulation of Autoimmune Arthritis by Herbal CAM  

UK PubMed Central (United Kingdom)

Rheumatoid arthritis (RA) is a debilitating autoimmune disease of global prevalence. The disease is characterized by synovial inflammation leading to cartilage and bone damage. Most of the conventional...Full Text Available

2011-01-01

250

Imaging oxygenation of human tumours  

UK PubMed Central (United Kingdom)

Tumour hypoxia represents a significant challenge to the curability of human tumours leading to treatment resistance and enhanced tumour progression. Tumour hypoxia can be detected by non-invasive and...Full Text Available

2007-04-01

251

Genomic imprinting and the social brain  

UK PubMed Central (United Kingdom)

Genomic imprinting refers to the parent-of-origin-specific epigenetic marking of a number of genes. This epigenetic mark leads to a bias in expression between maternally and paternally inherited imprinted...Full Text Available

2006-12-29

252

Gastrointestinal absorption of lead (/sup 203/Pb) in chicks: influence of lead, calcium, and age  

Energy Technology Data Exchange (ETDEWEB)

The present study was designed to investigate, in more detail, the mechanism of lead transport by the gastrointestinal tract and particularly the similarities or dissimilarities between lead and calcium in this process. The absorption of these metals was determined in 3-week-old white Leghorn cockerels, raised on a commercial diet or special diets, using an in vivo ligated loop procedure. The dose administered into the loop usually contained 0.5 ..mu..Ci /sup 203/Pb (and/or 0.1 ..mu..Ci /sup 47/Ca), 0.01 mM lead acetate (and/or 1 mM CaCl/sub 2/) in 0.5 ml of 0.15 M NaCl, pH 6.5. It was shown that lead is rapidly taken up by the intestinal tissue, and only slowly transferred into the circulation whereas calcium, also accumulated rapidly by the tissue, is rapidly released from the tissue in the serosal direction. The absorption processes of these cations show similar responses to various experimental ...

1981-10-01

253

Emergencies > Poisoning > Lead Poisoning | Browse EPA Topics...  

Science.gov (United States)

Accidents Accident Preparedness, Accident Prevention, Chemical Accidents, Radiation Accidents Characterization Contingency Plans National Contingency Plan (NCP), Oil Removal...

2011-01-20

254

Effect of lead exposure in children  

International Nuclear Information System (INIS)

Increasing prosperity and population-growth in many developing countries are resulting in accelerated growth in population of vehicles and vehicle-kilometers traveled. In Pakistan also, the number of vehicles has jumped from 0.8 million to about 4.0 million within 20 years, showing an overall increase of more than 400%. Accordingly, the consumption of petrol (motor spirit) has increased from 828,670 metric tons to 1,189,042 metric tons. The high content of lead in petrol is a serious issue, as the end- product is the release of lead into the environment. In Pakistan, prior to July 2001, lead-content in petrol was reported to be as high as 0.35-0.84 gram per liter. The reported lead-levels in air (micrograms/cubic centimeter) in different cities of Pakistan are: Karachi (1980-81) 0.13-0.24; Peshawar (1994-95) 0.21-0.79; Lahore (1993-94) 0.15-8.36 and (1999-2000) 0.89-7.85 and Rawalpindi (1999-2000) ...

255

Effect of an Active Abdominal Pulse Generator on Defibrillation Thresholds with a Dual-Coil, Transvenous ICD Lead System  

British Library Electronic Table of Contents (United Kingdom)

Effect of Abdominal Active Can on DFTs. Introduction: Many patients with implantable cardioverter defibrillators (ICDs) have older lead systems, which are usually not replaced at the time of pulse generator replacement unless a malfunction is noted. Therefore, optimization of defibrillation with these lead systems is clinically important. The objective of this prospective study was to determine if an active abdominal pulse generator (Can) affects chronic defibrillation thresholds (DFTs) with a dual-coil, transvenous ICD lead system. Methods and Results: The study population consisted of 39 patients who presented for routine abdominal pulse generator replacement. Each patient underwent two assessments of DFT using a step-down protocol, with the order of testing randomized. The distal right ...

2006-01-01

256

ELECTRICAL AND OPTICAL PROPERTIES OF LEAD-TIN ...  

Science.gov (United States)

... Abstract : Single crystals of Pb(x)Sn(1-x)Te alloy have been grown with o = or thin film evaporator. ...

1969-09-03

257

Diabetic complications and dysregulated innate immunity  

UK PubMed Central (United Kingdom)

Diabetes mellitus is a metabolic disorder that leads to the development of a number of complications. The etiology of each diabetic complication is undoubtedly multifactorial. We will focus...Full Text Available

258

Cultures of Death and Politics of Corpse Supply  

UK PubMed Central (United Kingdom)

SummaryNineteenth-century Vienna is well known to medical historians as a leading centre of medical research and education, offering easy access to patients and corpses to students...Full Text Available

2008-01-01

259

Color Fluorescence Ratio for Detection of Bronchial Dysplasia and Carcinoma In situ  

UK PubMed Central (United Kingdom)

BackgroundAutofluorescence bronchoscopy is more sensitive than conventional bronchoscopy for detecting early airway mucosal lesions. Decreased specificity can lead...Full Text Available

2009-07-15

260

Bladder outlet obstruction in male cystinuria mice  

UK PubMed Central (United Kingdom)

BackgroundCystinuria is the most common inherited cause of urinary tract stones in children. It can lead to obstructive uropathy, which is a major cause of renal...Full Text Available

2010-03-01

261

Berkeley Lab News Center: Today at Berkeley Lab  

Science.gov (United States)

who was appointed in July to lead the Defense Advanced Research Projects Agency, or DARPA, made visits last week to UC Berkeley, Stanford, UCLA and the California Institute of...

2011-08-27

262

Artificial and natural duplicates in pyrosequencing reads of metagenomic data  

UK PubMed Central (United Kingdom)

BackgroundArtificial duplicates from pyrosequencing reads may lead to incorrect interpretation of the abundance of species and genes in metagenomic studies. Duplicated reads were...Full Text Available

263

ACTIVE AEROELASTIC WING ROLLOUT ACCENTS 'BACK TO THE - NASA  

Science.gov (United States)

The traditional wing control surfacestrailing edge ailerons and the outboard leading edge flapsare used to provide the aerodynamic force needed to twist ...

264

A child with hyperferritinemia: Case report  

UK PubMed Central (United Kingdom)

Hereditary hyperferritinemia cataract syndrome (HHCS) is a rare condition caused by mutations in the gene coding for the light chain of ferritin; it does not lead to iron overload, but it is associated...Full Text Available

265

A 1500-year record of lead, copper, arsenic, cadmium, zinc level in Antarctic seal hairs and sediments  

British Library Electronic Table of Contents (United Kingdom)

To reconstruct the profiles of heavy metal levels in the South Ocean ecosystem of Antarctica, the concentrations of lead (Pb), copper (Cu), arsenic (As), cadmium (Cd), and zinc (Zn) in seal hairs and lake sediments spanning the past 1500?years from Fildes Peninsula of King George Island and in weathering lake sediments from Nelson Island of West Antarctica were determined. The lead contents in the seal hairs and the weathering sediments show a sharp increase since the late 1800s, very likely due to anthropogenic contamination from modern industries. After the 1980s, the Pb content in seal hairs dropped by one-third, apparently due to the reduced usage of leaded gasoline in the Southern Hemisphere. Copper arises mainly from the weathering process, and its level may be substantially affected...

2006-01-01

266

Transplacental movement of inorganic lead in early and late gestation in the mouse  

Energy Technology Data Exchange (ETDEWEB)

/sup 203/Pb(NO/sub 3/)/sub 2/ was administered i.v. to pregnant C57BL mice at different stages, from day 8 to day 18 of gestation. The whole animals or excised uteri were subjected to autoradiography or were autopsied for scintillation counting of excised organs. Lead appeared in embryonic and fetal tissues at all stages of gestation. Early (approx. day 8-11) lead was restricted mainly to the embryonic blood, suggesting that free lead was essentially not transferred to the embryo but may have been incorporated in the embryonic hemoglobin when the erythrocytes were formed in the yolk sac placenta (an extraembryonic membrane). From day 12 and later, an uptake was seen in the liver and the cartilaginous skeleton, and from day 14, a strong accumulation was found in calcified bone. This means that the overall fetal concentration increases successively with gestational age of the conceptus. The uptake in fetal liver may be ...

1983-10-01

267

Transplacental movement of inorganic lead in early and late gestation in the mouse  

International Nuclear Information System (INIS)

"2"0"3Pb(NO_3)_2 was administered i.v. to pregnant C57BL mice at different stages, from day 8 to day 18 of gestation. The whole animals or excised uteri were subjected to autoradiography or were autopsied for scintillation counting of excised organs. Lead appeared in embryonic and fetal tissues at all stages of gestation. Early (approx. day 8-11) lead was restricted mainly to the embryonic blood, suggesting that free lead was essentially not transferred to the embryo but may have been incorporated in the embryonic hemoglobin when the erythrocytes were formed in the yolk sac placenta (an extraembryonic membrane). From day 12 and later, an uptake was seen in the liver and the cartilaginous skeleton, and from day 14, a strong accumulation was found in calcified bone. This means that the overall fetal concentration increases successively with gestational age of the conceptus. The uptake in fetal liver may be related to the ...

268

Target space duality II: applications  

Energy Technology Data Exchange (ETDEWEB)

We apply the framework developed in Target space duality I: general theory. We show that both nonabelian duality and Poisson-Lie duality are examples of the general theory. We propose how the formalism leads to a systematic study of duality by studying few scenarios that lead to open questions in the theory of Lie algebras. We present evidence that there are probably new examples of irreducible target space duality.

2000-09-25

269

Quench propagation in AFM Bi-2223 conductors for current lead applications  

CERN Document Server

In this paper, the authors report on the electrical and thermal properties of Bi-2223 composite conductors prepared by the "accordion-folding method" (AFM). Thermal behavior study on AFM Bi-2223 conductors similar to those that have been successfully used to assemble the cold stage of low-loss current leads for CERN, has been performed by using a newly developed experimental apparatus that is described in detail. (7 refs).

2001-01-01

270

Polymorphisms of delta-aminolevulinic acid dehydratase (ALAD) and peptide transporter 2 (PEPT2) genes in children with low-level lead exposure  

UK PubMed Central (United Kingdom)

Low-level lead exposure during early childhood has long been associated with altered neurocognitive development and diminished cognitive functions. Over nine thousand U.S. industrial facilities...Full Text Available

2009-11-01

271

Our campuses :: University of Southampton  

Wastenet

... The National Oceanography Centre, Southampton is one of the world's leading research centres for the study of ocean and earth sciences. Southampton General Hospital One of the country's leading teaching hospitals and the base for the University's School of Medicine. Winchester School of Art Founded in 1863, Winchester School of Art is based 12 miles (20 kilometres) north of Southampton in the historic city of Winchester,...

272

Nondestructive determination of airborne lead particulates by the radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Airborne lead particulates collected on a membrane filter were determined by the nondestructive X-ray fluorescence method. The gamma/X radionuclide source "2"4"1Am/Ag and a scintillation detector with a NaI/Tl crystal were used for the excitation and detection, respectively, of L X-rays of Pb. One can say, with reference to the obtained results, that the sensitivity and accuracy of the measurement is more than adequate for monitoring the Pb level in air. (author).

1980-01-01

273

Effects of xylitol on the absorption of /sup 203/Pb in mice and cockerels  

Energy Technology Data Exchange (ETDEWEB)

Earlier studies have indicated that xylitol may increase the absorption and urinary excretion of dietary oxalate. It has also been indicated that xylitol increases the absorption of calcium. Intestinal absorption of lead, a divalent contaminant in the diet, is in many respects similar to that of calcium. The purpose of this study was to evaluate the effects of xylitol on the intestinal absorption of lead using two different approaches: the in situ ligated intestinal loop technique in cockerels and gastric gavage in mice.

1986-07-01

274

EFFECTS OF PH AND PHOSPHATE ON METAL DISTRIBUTION WITH EMPHASIS ON AS SPECIATION AND MOBILIZATION IN SOILS FROM A LEAD SMELTING SITE  

Science.gov (United States)

Arsenic in soils from the Asarco Lead Smelter in East Helena, Montana was characterized by X-ray absorption spectroscopy (XAS). As oxidation state and geochemical speciation were analyzed as a function of depth (two sampling sites) and surface distribution. These results were c...

275

Diffraction studies of nanocrystals: theory and experiment  

International Nuclear Information System (INIS)

Based on theoretical calculations of powder diffraction data it is shown that the assumption of the infinite crystal lattice for small particles is not justified, leads to significant changes of the diffraction patterns, and may lead to erroneous interpretation of the experimental results. An alternate evaluation of diffraction data of nanoparticles, based on the so-called 'apparent lattice parameter', alp, is proposed. (author)

2001-09-23

276

Development of zirconium alloys. Part II  

Science.gov (United States)

A number of alloys of zirconium have been investigated as part of a program aimed at improving the high-temperature tensile and creep strength of zirconium. These alloys include aluminum, beryllium, lead, magnesium, molybdenum, niobium, tantalum, tin, titanium, tungsten, vanadium, and zinc, binary and ternary alloys. The data indicate that aluminum, lead, molybdenum niobium, tin, titanium, tungsten, and vanadium can be used successfully to harden zirconium, and that aluminum, tin, titanium, and vanadium are particularly effective in maintaining the strength of zirconium at elevated temperatures.

1952-01-02

277

Determination of lead in soil samples by "2"0"3Pb radioisotope dilution substoichiometric method  

International Nuclear Information System (INIS)

A procedure for the determination of lead in soil samples by "2"0"3Pb radioisotope dilution substoichiometric method is described. Japan NIES No.2 river clay standard sample and 83-40 Tibet soil standard sample were determined. The obtained values were in good agreement with reference values. The standard deviation of the method was less then 5%. Detection limit was about 0.1 #mu#g Pb.

278

Chloropicrin formation during oxidative treatments in the preparation of drinking water  

Energy Technology Data Exchange (ETDEWEB)

Chlorination of water can lead to the formation of chloropicrin. The numerous potential precursors (of various reactivities) observed during this study, confirm this hypothesis. Combination of ozonation and chlorination can also lead to the formation of this compound, dangerous to health; however, the conditions of the formation and particularly the impact of a nitration reaction in the gas phase are still not clearly defined.

1985-12-01

279

A new treatment of mixed virtual and real IR-singularities  

Energy Technology Data Exchange (ETDEWEB)

We discuss the determination of the infrared singularities of massive one-loop 5-point functions with Mellin-Barnes (MB) representations. Massless internal lines may lead to poles in the {epsilon} expansion of the Feynman diagram, while unresolved massless final state particles give endpoint singularities of the phase space integrals. MB integrals are an elegant tool for their common treatment. An evaluation by taking residues leads to inverse binomial sums. (orig.)

2008-01-15

280

A case study in atmospheric lead pollution of Northern-German coastal regions  

Energy Technology Data Exchange (ETDEWEB)

Transport and deposition of atmospheric lead over the coastal zone of Northern Germany are investigated. It is shown that marked differences in the impact of the ecologically valuable wadden sea areas can occur between summer and winter time. Due to the formation of sea breeze systems in summer the coastal zone is likely to be less stressed than in winter when the pollutant is confined to a shallow layer above ground. (orig.) 10 refs.

1998-12-31

281

Stagnation region heat transfer: The influence of turbulence parameters, Reynolds number and body shape  

Science.gov (United States)

The effect of velocity gradient on stagnation region heat transfer augmentation by free stream turbulence was investigated. Heat transfer was measured in the stagnation region of four models with elliptical leading edges with ratios of major to minor axes of 1:1, 1.5:1, 2.25:1, and 3:1. Four geometrically similar, square bar, square mesh, biplane grids were used to generate free stream turbulence with different intensities and length. Heat transfer measurements were made for the following ranges of parameters: Reynolds number, based on leading edge diameter, 37,000 to 228,000; dimensionless leading edge velocity gradient, 1.20 to 1.80; turbulence intensity, 1.1 to 15.9%; and length scale to leading edge diameter ratio, 0.05 to 0.30. Stagnation point heat transfer augmentation by free stream turbulence can be predicted using a modified version of a previously developed correlation for a circular ...

1994-02-01

282

Radiation exposure to anesthesiologist and nurse in the orthopedic room  

International Nuclear Information System (INIS)

We report the radiation exposure dose received by the anesthesiologist and nurse in the orthopaedic operating room, when a fluoroscopic image intensifier is in use. This study was done in 12 femoral neck fracture operations performed from January to May 1995. Radiation was monitored with the MYDOSE MINIX PDM 107 made by Aloka Co. which were attached in front and behind the nurse's lead apron, in front of the lead apron of the anesthesiologist. The average imaging time was 9.78 min. The average radiation dose in front of the anesthesiologist is lead apron was 2.08#mu#SV, and in front and behind the nurse's lead apron were 5.67#mu#SV, 0.08#mu#SV respectively. This study and review of the literature indicate that the operating room anesthesiologist and nurse receive a lower exposure than the orthopaedist. We can disregard the problem of radiation exposure to the anesthesiologist and nurse during an ...

283

Preconcentration and determination of trace amounts of lead (II) as thenoyltrifluoroacetone complex with dibenzo-18-crown-6 by synergistic extraction and atomic absorption spectrometry  

Energy Technology Data Exchange (ETDEWEB)

A new method for the preconcentration and determination of trace amounts of lead at the {mu}g/L level in natural waters has been established based on the formation of the thenoyltrifluoroacetone (TTA) complex with dibenzo-18-crown-6 (DB18C6) by means of synergistic extraction and back-extraction combined with atomic absorption spectrometry (AAS). The effect of various factors (synergism with TTA and DB18C6, shaking time, preconcentration factor, composition of the extracted species, and foreign ions etc.) on the extraction and back-extraction of lead has been investigated in detail. The lead-TTA chelate in o-dichlorobenzene forms a stable adduct with DB18C6 as Pb(TTA){sub 2} DB18C6. The stability constant ({beta}) of the adduct determined by curve fitting method was log {beta} = 4.2. The amount of lead in natural waters such as tap water (Kanazawa University) and Kakehashi river (Komatsu City) ...

1998-07-01

284

Mechanisms of renal handling of lead  

International Nuclear Information System (INIS)

The relative roles of glomerular filtration, tubular reabsorption and tubular secretion in lead handling were evaluated using renal clearance technique, stop-flow analysis, and renal lead accumulation. In addition, the effect of altering acid-base status on renal handling of Pb was determined. Clearance of ultrafilterable lead was measured in anesthetized dogs during infusion of "2"0"3Pb with small doses of carrier Pb(0.5 to 50 #mu#g/kg/h). Filterable lead concentration was estimated by in vitro ultrafiltration of non-anticoagulated plasma. Fractional excretion of Pb was calculated using creatinine clearance to estimate glomerular filtration rate. Dogs in acute metabolic acidosis had the lowest fractional excretion of ultrafilterable Pb (< 0.1); those in alkalosis had high fractional Pb excretion (0.75 to 2.5) while normal dogs were intermediate (0.1 to .4). The fractional excretion of Pb during ...

285

In vivo evaluation of a lead-labeled monoclonal antibody using the DOTA ligand  

International Nuclear Information System (INIS)

The aim of this study was to assess the utility of a radioimmunoconjugate containing a lead radionuclide for therapy and scintigraphy applications. The radioimmunoconjugate evaluated consisted of a bifunctional DOTA ligand and monoclonal antibody (MAb) B72.3 using athymic mice bearing LS-174T tumors, human colon carcinoma xenografts. In the studies reported here, the lead-203-DOTA complex itself was first demonstrated to have in vivo stability. MAb B72.3 was then conjugated with the DOTA ligand and labeled with "2"0"3Pb, and the immunoreactivity of B72.3 was maintained. The localization of the radioimmunoconjugate to tumor tissue and other select organs paralleled that of DOTA-"1"2"5I-B72.3, suggesting a similar metabolic pattern of the two radioimmunoconjugates. Thus, the DOTA-metal complex does not alter the behavior of the radioimmunoconjugate. Tumor localization of the "2"0"3Pb-DOTA-B72.3 conjugate was demonstrated with biodistribution ...

1998-05-01

286

Distribution of lead in lactating mice and suckling offspring with special emphasis on the mammary gland  

Energy Technology Data Exchange (ETDEWEB)

The distribution of lead in lactating mice and suckling offspring was studied with whole body autoradiography at 4 and 24 h after a single intravenous injection of {sup 203}Pb (50 mmol Pb/kg) to the dams. In the lactating mice on day 14 of lactation, the highest uptake of radioactivity at 4 h after administration was recorded in renal cortex, skeleton and liver. A high uptake was also evident in the mannary gland. At 24 h after administration, the radioactivity had decreased in most organs except in the skeleton. In the suckling pups, exposed to lead only via dams` milk for 24 h, the highest level of radioactivity was present in the intestinal mucosa and a much lower level of radioactivity was present in the skeleton. The mammary glands from mice given three daily intravenous injections of 240 {mu}mol Pb/kg were examined with X-ray microanalysis. At 4 h after the last injection, lead was found associated with casein ...

1996-01-01

287

Distribution of lead in lactating mice and suckling offspring with special emphasis on the mammary gland  

International Nuclear Information System (INIS)

The distribution of lead in lactating mice and suckling offspring was studied with whole body autoradiography at 4 and 24 h after a single intravenous injection of "2"0"3Pb (50 mmol Pb/kg) to the dams. In the lactating mice on day 14 of lactation, the highest uptake of radioactivity at 4 h after administration was recorded in renal cortex, skeleton and liver. A high uptake was also evident in the mannary gland. At 24 h after administration, the radioactivity had decreased in most organs except in the skeleton. In the suckling pups, exposed to lead only via dams' milk for 24 h, the highest level of radioactivity was present in the intestinal mucosa and a much lower level of radioactivity was present in the skeleton. The mammary glands from mice given three daily intravenous injections of 240 #mu#mol Pb/kg were examined with X-ray microanalysis. At 4 h after the last injection, lead was found associated with casein micelles ...

288

HALO - the helium and lead observatory for supernova neutrinos  

Energy Technology Data Exchange (ETDEWEB)

The Helium and Lead Observatory (HALO) is a supernova neutrino detector under development for construction at SNOLAB. It is intended to fulfill a niche as a long term, low cost, high livetime, and low maintenance, dedicated supernova detector. It will be constructed from 80 tonnes of lead, from the decommissioning of the Deep River Cosmic Ray Station, and instrumented with approximately 384 meters of {sup 3}He neutron detectors from the final phase of the SNO experiment. Charged- and Neutral-Current neutrino interactions in lead expel neutrons from the lead nuclei making a burst of detected neutrons the signature for the detection of a supernova. Existing neutrino detectors are mostly of the water Cerenkov and liquid scintillator types, which are primarily sensitive to electron anti-neutrinos via charged-current interactions on the hydrogen nuclei in these materials. By contrast, the large neutron ...

2008-11-01

289

Effect of lead in the laboratory mouse. 1. Influence of pregnancy upon absorption, retention, and tissue distribution of radiolabeled lead  

Energy Technology Data Exchange (ETDEWEB)

Whole-body retention and excretion following a single oral dose of radiolabeled lead (/sup 203/Pb) in chronically lead-exposed pregnant BK:W mice were examined over 10-13 days. This was compared with values in similarly treated nonpregnant females and in ip injected females. Whole-body and bone retention were greater in injected than in orally dosed nonpregnant females; gastrointestinal absorption was estimated from this difference. Whole-body retention in the pups was measured at birth and at the end of the experiment. Whole-body retentions in pregnant females and in their pups at birth were significantly raised after treatment at Gestational Day 17, but not after treatment at Gestational Day 11, 14, 20, 23, or 26. Pup body burdens at birth were significantly and positively correlated with maternal retention. Measurement of radioactivity in bone, kidney, brain, heart, and liver of adults at the end of the experiments showed significantly ...

1986-12-01

290

Effect of lead in the laboratory mouse. 1. Influence of pregnancy upon absorption, retention, and tissue distribution of radiolabeled lead  

International Nuclear Information System (INIS)

Whole-body retention and excretion following a single oral dose of radiolabeled lead ("2"0"3Pb) in chronically lead-exposed pregnant BK:W mice were examined over 10-13 days. This was compared with values in similarly treated nonpregnant females and in ip injected females. Whole-body and bone retention were greater in injected than in orally dosed nonpregnant females; gastrointestinal absorption was estimated from this difference. Whole-body retention in the pups was measured at birth and at the end of the experiment. Whole-body retentions in pregnant females and in their pups at birth were significantly raised after treatment at Gestational Day 17, but not after treatment at Gestational Day 11, 14, 20, 23, or 26. Pup body burdens at birth were significantly and positively correlated with maternal retention. Measurement of radioactivity in bone, kidney, brain, heart, and liver of adults at the end of the experiments showed significantly ...

291

{delta}-excitations and the three-nucleon force  

Energy Technology Data Exchange (ETDEWEB)

We study the three-nucleon force in chiral effective field theory with explicit {delta}-resonance degrees of freedom. We show that up to next-to-next-to-leading order, the only contribution to the isospin symmetric three-nucleon force involving the spin-3/2 degrees of freedom is given by the two-pion-exchange diagram with an intermediate delta, frequently called the Fujita-Miyazawa force. We also analyze the leading isospin-breaking corrections due to the delta. For that, we give the first quantitative analysis of the delta quartet mass splittings in chiral effective field theory including the leading electromagnetic corrections. The charge-symmetry breaking three-nucleon force due to an intermediate delta excitation is small, of the order of a few keV.

2008-06-15

292

Tropospheric chemistry of natural hydrocarbons, aldehydes, and peroxy radicals: Their connections to sulfuric acid production and climate effects  

International Nuclear Information System (INIS)

Recent work has shown that natural hydrocarbon emissions can significantly affect the levels of urban and regional tropospheric ozone. We report on the reactivities of these biogenic trace gases, particularly isoprene, focusing on their importance in the production of aldehydes and peroxy radicals, leading to increased levels of hydrogen over regional forests. Hydrogen peroxide can lead to the wet oxidation of sulfur dioxide to acidic sulfate in aerosols, fogs, and clouds. In turn, acidic sulfate can act to as a light scattering aerosol and a source of cloud condensation nuclei (CCN), potentially leading to global cooling. Aerosol sulfate and other dissolved organic and inorganic compounds can also play important roles as a greenhouse species in the lower troposphere.

1993-08-08

293

The separation of "2"0"3Pb from a thallium target  

International Nuclear Information System (INIS)

"2"0"3Pb, an ideal radionuclide for toxicological studies, can be artificially produced by bombardment of a thallium target but due to the extreme toxicity of thallium the lead has to be separated completely from the thallium. A single step method is here described consisting of removing the thallium from a dilute acid chloride solution using a continuous ethyl ether extraction. Essentially all of the thallium and almost none of the lead is removed in a 3-hr extraction. Because the ether is recycled, only about 30 ml are needed. If other contaminants are introduced from the bombardment and its subsequent manipulations, an additional step is used in which the lead is extracted from an iodide solution with methyl isopropyl keton. (U.K.).

294

Roles of biomarkers in evaluating interactions among mixtures of lead, cadmium and arsenic  

British Library Electronic Table of Contents (United Kingdom)

Human exposure to environmental chemicals is most correctly characterized as exposure to mixtures of these agents. The metals/metalloids, lead (Pb), cadmium (Cd), and arsenic (As), are among the leading toxic agents detected in the environment. Exposure to these elements, particularly at chronic low dose levels, is still a major public health concern. Concurrent exposure to Pb, Cd, or As may produce additive or synergistic interactions or even new effects that are not seen in single component exposures. Evaluating these interactions on a mechanistic basis is essential for risk assessment and management of metal/metalloid mixtures. This paper will review a number of individual studies that addressed interactions of these metals/metalloids in both experimental and human exposure studies with...

2008-01-01

295

Renewable energy systems - the environmental impact approach. Paper no. IGEC-1-008  

International Nuclear Information System (INIS)

High energy consumption and the world population increase will lead to a shrinking use of fossil fuels. The combustion of Fossil fuel leads to the increase of carbon dioxide concentration in the atmosphere which leads to the probable increase of global warming. Therefore, concerns about carbon dioxide emissions may discourage widespread dependence on fossil fuels and encourage the development and use of renewable energy systems employing a variety of technologies Renewable energy systems have themselves an environmental impact. Land use and material employed are two areas that may have an adverse impact to the positive environmental picture of the renewable energy systems. The objective of this paper is to analyze these impacts with the use of a very powerful tool, the Life Cycle Assessment. (author)

2005-06-12

296

Measurement of dijet cross sections for events with a leading neutron in photoproduction at HERA  

Energy Technology Data Exchange (ETDEWEB)

Differential cross sections for dijet photoproduction in association with a leading neutron using the reaction e{sup +}+p{yields}e{sup +}+n+jet+jet+X{sub r} have been measured with the ZEUS detector at HERA using an integrated luminosity of 6.4 pb{sup -1}. The fraction of dijet events with a leading neutron in the final state was studied as a function of the jet kinematic variables. The cross sections were measured for jet transverse energies E{sub T}{sup jet}>6 GeV, neutron energy E{sub n}>400 GeV, and neutron production angle {theta}{sub n}<0.8 mrad. The data are broadly consistent with factorization of the lepton and hadron vertices and with a simple one-pion-exchange model.

2001-02-26

297

Lead, cadmium, chromium, cobalt, and copper in chicken feathers from Tuskegee, Alabama  

Energy Technology Data Exchange (ETDEWEB)

The feather has been widely used as a indicator tissue of metal exposure in birds. The feathers were collected from Tuskegee University poultry farm (TUPF) and Harrison Poultry farm (HPF) chicken and analyzed by Inductively Coupled Plasma Atomic Emission Spectroscopy for lead, cadmium, cobalt, chromium, and copper contaminations. The mean levels of lead, cadmium, cobalt, chromium, and copper in TUPF chicken were 3.67, 0.13, 12.23, 0.22, and 7.71 ppm, respectively, and in HPF chicken were 5.32, 0.096, 11.03, 0.15, and 8.06 ppm, respectively. The mean levels of these metals did not show any significant difference between TUPF and HPF chicken.

1994-12-31

298

Fast leak in channel H9  

International Nuclear Information System (INIS)

The loss of seal of the H9 channel in vacuum, freeing the entire cross section of the front part, leads to a fast leak that progresses rapidly. The effect of depressurizing the reflector can leads to shutdown of the shutdown rod pumps. The source changer associated with the channel fills completely before the valve closes. All of the leak water remains contained within the source changer containment. After the valves open, cooling of the fuel element is handled by natural convection, requiring a reversal of the flow between the plates. This changeover, which takes place at a relatively low pressure level, could lead to local boiling in the fuel element. Consequently, irreversible transformations cannot be excluded as possibilities for the fuel element and even for the control rod. Subsequently, the can is refilled with heavy water with establishment of the usual pressure levels.

299

Effects of organic and inorganic lead on the oxygen equilibrium curves of the fresh water field crab, Barytelphusa guerini  

Energy Technology Data Exchange (ETDEWEB)

Haemocyanin serves as normal transporter of oxygen in many Arthropods. The oxygen equilibrium curves have been described for the haemocyanins of many Arthropods and Molluscs. Oxygen equilibrium curves of the blood reveal the relationship between the oxygen tension and the percentage saturation of the haemocyanin. The shape of the oxygen equilibrium curves vary in position from sigmoid to hyperbolic in different animals or even undulatory as shown in some chitons. Oxygen equilibrium curves are known to be influenced by pH, temperature and inorganic ions. The effect of environmental pollutants like the heavy metals on the oxygen equilibrium curves of the fresh water crab has not been previously reported. One of the toxic heavy metals with regard to aquatic organisms is lead. Hence the present study was designed to determine the effect of organic and inorganic lead on the oxygen equilibrium curve of the fresh water crab, Barytelphusa guerini.

1989-02-01

300

Canadian soil quality criteria for lead, copper, arsenic, cadmium and mercury  

Energy Technology Data Exchange (ETDEWEB)

National soil quality criteria for the protection of ecological receptors, including livestock and wildlife, are currently under development in Canada. Based on an evaluation of direct soil contact and soil and food ingestion pathways for sensitive species, soil quality criteria for lead, copper, arsenic, cadmium and mercury for three land use categories have been derived. The draft values, in mg/kg soil, for agricultural, residential/parkland, commercial/industrial land uses are: mercury, 4, 4, 30; copper, 62, 62, 100; cadmium, 10, 10, 27; lead, 70, 250, 400; arsenic, 17, 17, 26. Critical data requirements in developing soil quality criteria are also reviewed.

1995-12-31

301

Biosorption of heavy metals on fungal biomass  

Energy Technology Data Exchange (ETDEWEB)

A method of using fungi in removing heavy metal from wastewater was discussed. Fungi for this purpose can be obtained inexpensively, and on a constant basis from industrial fermentation processes. The biosorption of lead, cadmium and nickel on fungal stock cultures, was investigated. In these experiments, the fungal stock used was Aspergillus niger and Rhizopus stolonfier. Alkali pre-treatment of the fungal biomass improved the metal biosorptive capacity in comparison to live cells. The effect of alkali treatment, however, varied,showing highest biosorptive capacity for lead and least for nickel. Results showed that metal biosorption of metallic ions increased with an increase in pH from 3.2 to 4.0. Equilibrium times of five hours were observed for the biosorption of lead and cadmium, while the equilibrium time for nickel was three hours. 10 refs., 3 tabs., 7 figs.

1996-09-01

302

Wrinkled hard skins on polymers created by focused ion beam  

UK PubMed Central (United Kingdom)

A stiff skin forms on surface areas of a flat polydimethylsiloxane (PDMS) upon exposure to focused ion beam (FIB) leading to ordered surface wrinkles. By controlling the FIB fluence and area of exposure...Full Text Available

2007-01-23

303

Who Should Receive Life Support During a Public Health Emergency? Using Ethical Principles to Improve Allocation Decisions  

UK PubMed Central (United Kingdom)

A public health emergency such as an influenza pandemic will lead to shortages of mechanical ventilators, critical care beds, and other potentially life saving treatments. This will raise difficult...Full Text Available

2009-01-20

304

Vitamin C and E Supplementation Effects in Professional Soccer Players Under Regular Training  

UK PubMed Central (United Kingdom)

Exercise training is known to induce an increase in free radical production potentially leading to enhanced muscle injury. Vitamins C and E are well known antioxidants that may prevent muscle cell damage....Full Text Available

305

Vertebroplasty and Kyphoplasty Can Restore Normal Spine Mechanics following Osteoporotic Vertebral Fracture  

UK PubMed Central (United Kingdom)

Osteoporotic vertebral fractures often lead to pain and disability. They can be successfully treated, and possibly prevented, by injecting cement into the vertebral body, a procedure known as vertebroplasty....Full Text Available

306

Use of antivascular endothelial growth factor for diabetic macular edema  

UK PubMed Central (United Kingdom)

BackgroundDiabetic macular edema (DME) is one of the manifestations of diabetic retinopathy leading to loss of central vision and visual acuity. It manifests itself with swelling...Full Text Available

2010-01-01

307

Unusual occurrence of accessory central cusp in the maxillary second primary molar  

UK PubMed Central (United Kingdom)

Accessory cusp present on the occlusal surface may seldom pose problems. While its presence may not be a cause for alarm in most instances, it can sometimes lead to serious consequences if it is damaged....Full Text Available

2011-04-01

308

Two-phase flow regime modeling  

International Nuclear Information System (INIS)

This paper describes a long term course of research into the fundamentals of two phase flow regime dynamics that had lead to a differential description of regime properties. The development has included experiment, microscale simulation, and mathematical averaging to produce a dynamic equation for interfacial area.

1981-03-01

309

Treatment with LL-37 Peptide Enhances Antitumor Effects Induced by CpG Oligodeoxynucleotides Against Ovarian Cancer  

UK PubMed Central (United Kingdom)

AbstractThere is an urgent need for innovative therapies against ovarian cancer, one of the leading causes of death from gynecological cancers in the United States. Immunotherapy employing...Full Text Available

2009-04-01

310

Transplantation of allogeneic T cells alters iron homeostasis in NOD/SCID mice  

UK PubMed Central (United Kingdom)

Iron overload is common in patients undergoing allogeneic hematopoietic cell transplantation (HCT), but the mechanisms leading to overload are unknown. Here, we determined iron levels and the expression...Full Text Available

2009-02-19

311

Transmitted drug resistance in nonsubtype B HIV-1 infection  

UK PubMed Central (United Kingdom)

HIV-1 nonsubtype B variants account for the majority of HIV infections worldwide. Drug resistance in individuals who have never undergone antiretroviral therapy can lead to early failure and...Full Text Available

2009-09-01

312

Therapeutic Vaccination in Chronic Hepatitis B: Preclinical Studies in the Woodchuck  

UK PubMed Central (United Kingdom)

Recommended treatment of chronic hepatitis B with interferon-α and/or nucleos(t)ide analogues does not lead to a satisfactory result. Induction of HBV-specific T cells by therapeutic...Full Text Available

2010-01-01

313

The solar aircraft  

Energy Technology Data Exchange (ETDEWEB)

A discussion is given in a popular manner of the solar powered aircraft Solair I. The achievements of the designer are detailed, and trial runs leading up to the first successful flight are given. Technical data of Solair I are listed, and brief news items about it are presented.

1983-03-01

314

The role of AMPK in psychosine mediated effects on oligodendrocytes and astrocytes: Implication for Krabbe Disease  

UK PubMed Central (United Kingdom)

Krabbe disease (KD) is an inherited neurological disorder caused by the deficiency of galactocerebrosidase activity resulting in accumulation of psychosine, which leads to energy depletion,...Full Text Available

2008-06-01

315

The relationship between change in subjective outcome and change in disease: a potential paradox  

UK PubMed Central (United Kingdom)

BackgroundResponse shift theory suggests that improvements in health lead patients to change their internal standards and re-assess former health states as worse than initially rated...Full Text Available

2010-09-01

316

The potential role of phrenic nucleus glutamate receptor subunits in mediating spontaneous crossed phrenic activity in neonatal rat  

UK PubMed Central (United Kingdom)

Cervical spinal cord hemisection rostral to the phrenic nucleus leads to paralysis of the ipsilateral hemidiaphragm in adult rats. Respiratory function can be restored to the paralyzed hemidiaphragm...Full Text Available

2009-08-01

317

The electric fuel zinc-air battery option  

Energy Technology Data Exchange (ETDEWEB)

With specific energy of more than 200 Wh/kg, the Electric Fuel zinc-air battery delivers as much as eight times the energy of lead-acid traction battery, more than twice the energy of the nearest advanced-battery competitor, and as much energy as a tank of gasoline. (author)

1995-12-31

318

The antimicrobial resistance patterns and associated determinants in Streptococcus suis isolated from humans in southern Vietnam, 1997-2008  

UK PubMed Central (United Kingdom)

BackgroundStreptococcus suis is an emerging zoonotic pathogen and is the leading cause of bacterial meningitis in adults in Vietnam. Systematic data on the antimicrobial...Full Text Available

319

The Differential Expression of Aqueous Soluble Proteins in Breast Normal and Cancerous Tissues in Relation to Stage and Grade of Patients  

UK PubMed Central (United Kingdom)

Breast cancer is a leading cause of female deaths worldwide. In Malaysia, it is the most common form of female cancer while Infiltrating ductal carcinoma (IDC) is the most common form of breast cancer....Full Text Available

2010-01-01

320

The Candida albicans Dse1 Protein Is Essential and Plays a Role in Cell Wall Rigidity, Biofilm Formation, and Virulence  

UK PubMed Central (United Kingdom)

The fungal pathogen Candida albicans is one of the leading causative agents of death in immunocompromised individuals. It harbors an arsenal of cell wall anchored factors that are implicated...Full Text Available

2011-01-01

321

The Aging Heart and Post-Infarction Left Ventricular Remodeling  

UK PubMed Central (United Kingdom)

Aging is a risk factor for heart failure, which is a leading cause of death world-wide. Elderly patients are more likely than young patients to experience a myocardial infarction (MI) and are...Full Text Available

2010-12-28

322

Test-retest reliability of knee kinesthesia in healthy adults  

UK PubMed Central (United Kingdom)

BackgroundSensory information from mechanoreceptors in the skin, muscles, tendons, and joint structures plays an important role in joint stability. A joint injury can lead to disruption...Full Text Available

323

Technical approaches for mouse models of human disease  

UK PubMed Central (United Kingdom)

The mouse is the leading organism for disease research. A rich resource of genetic variation occurs naturally in inbred and special strains owing to spontaneous mutations. However, one can also obtain...Full Text Available

2011-05-01

324

Teaching, learning, and leading.  

Science.gov (United States)

Instructional systems design is a process for assessing learning needs, creating instructional programs, and evaluating effectiveness of learning. We discuss the benefits of including instructional systems design theory and practice in the curriculum, with an emphasis on making the process relevant for student nurse anesthetists. PMID:10488275

1999-02-01

325

System Analysis for Decay Heat Removal in Lead-Bismuth Cooled Natural Circulated Reactors  

Science.gov (United States)

Decay heat removal analyses for lead-bismuth cooled natural circulation reactors are described in this paper. A combined multi-dimensional plant dynamics code (MSG-COPD) has been developed to conduct the system analysis for the natural circulation reactors. For the preliminary study, transient analysis has been performed for a 100 MWe lead-bismuth-cooled reactor designed by Argonne National Laboratory (ANL). In addition, decay heat removal characteristics of a 400 MWe lead-bismuth-cooled natural circulation reactor designed by Japan Nuclear Cycle Development Institute (JNC) has been evaluated by using MSG-COPD. PRACS (Primary Reactor Auxiliary Cooling System) is prepared for the JNC's concept to get sufficient heat removal capacity. During 2000 sec after the transient, the outlet temperature shows increasing tendency up to the maximum temperature of 430 Centigrade, because the buoyancy force in a primary ...

2002-07-01

326

Submergence-Induced Morphological, Anatomical, and Biochemical Responses in a Terrestrial Species Affect Gas Diffusion Resistance and Photosynthetic Performance  

UK PubMed Central (United Kingdom)

Gas exchange between the plant and the environment is severely hampered when plants are submerged, leading to oxygen and energy deficits. A straightforward way to reduce these shortages of oxygen and...Full Text Available

2005-09-01

327

Structure of plant nuclear and ribosomal DNA containing chromatin.  

UK PubMed Central (United Kingdom)

Digestion of plant chromatin from Brassica pekinensis and Matthiola incana with staphylococcus nuclease leads to a DNA repeat of 175 plus or minus 8 and a core size of 140 base pairs. DNase I digestion...Full Text Available

1979-11-10

328

Stressed-Induced TMEM135 Protein Is Part of a Conserved Genetic Network Involved in Fat Storage and Longevity Regulation in Caenorhabditis elegans  

UK PubMed Central (United Kingdom)

Disorders of mitochondrial fat metabolism lead to sudden death in infants and children. Although survival is possible, the underlying molecular mechanisms which enable this outcome have not yet been...Full Text Available

329

Strategies for the uses of lanthanide NMR shift probes in the determination of protein structure in solutio. Application to the EF calcium binding site of carp parvalbumin.  

UK PubMed Central (United Kingdom)

The homologous sequences observed for many calcium binding proteins such as parvalbumin, troponin C, the myosin light chains, and calmodulin has lead to the hypothesis that these proteins have homologous...Full Text Available

1980-10-01

330

Stefan Problem of Detonation Theory.  

Science.gov (United States)

A certain model of one-dimensional detonation waves leads to a Stefan problem: the unknown f satisfies Burgers equations on the two sides of a moving discontinuity at which it is given (f, say) and the jump in it derivative (corresponding to the exothermi...

1985-01-01

331

Situational Analysis of Household Energy and Biomass Use and Associated Health Burden of Indoor Air Pollution and Mitigation Efforts in Pakistan  

UK PubMed Central (United Kingdom)

Biomass fuel burning leads to high levels of suspended particulate matter and hazardous chemicals in the indoor environment in countries where it is in common use, contributing significantly to indoor...Full Text Available

2010-07-01

332

Short-amplitude high-frequency wing strokes determine the aerodynamics of honeybee flight  

UK PubMed Central (United Kingdom)

Most insects are thought to fly by creating a leading-edge vortex that remains attached to the wing as it translates through a stroke. In the species examined so far, stroke amplitude is large, and...Full Text Available

2005-12-13

333

Short Stat5-Interacting Peptide Derived from Phospholipase C-?3 Inhibits Hematopoietic Cell Proliferation and Myeloid Differentiation  

UK PubMed Central (United Kingdom)

Constitutive activation of the transcription factor Stat5 in hematopoietic stem/progenitor cells leads to various hematopoietic malignancies including myeloproliferative neoplasm (MPN). Our recent study...Full Text Available

334

Self-organization of nickel atoms in silicon  

British Library Electronic Table of Contents (United Kingdom)

We present experimental evidence for self-organization of nickel microparticles in silicon under certain thermodynamic conditions of nickel diffusion doping. The concentration and distribution of the microparticles in silicon are very uniform. Additional anneals lead to self-ordering of the impurity microparticles.

2011-01-01

335

Selective Inflammatory Pain Insensitivity in the African Naked Mole-Rat (Heterocephalus glaber)  

UK PubMed Central (United Kingdom)

In all mammals, tissue inflammation leads to pain and behavioral sensitization to thermal and mechanical stimuli called hyperalgesia. We studied pain mechanisms in the African naked mole-rat, an unusual...Full Text Available

2008-01-01

336

Seasonal changes in lead absorption in laboratory rats.  

UK PubMed Central (United Kingdom)

A retrospective study of the relationship of season to the absorption of radiolead in laboratory rats was performed using data representing 305 animals from 36 experiments over 6 calendar years. Male...Full Text Available

1987-08-01

337

Risk of symptomatic heterotopic ossification following plate osteosynthesis in multiple trauma patients: an analysis in a level-1 trauma centre  

UK PubMed Central (United Kingdom)

BackgroundSymptomatic heterotopic ossification (HO) in multiple trauma patients may lead to follow up surgery, furthermore the long-term outcome can be restricted. Knowledge of the...Full Text Available

338

Risedronate Prevents Early Radiation-Induced Osteoporosis in Mice at Multiple Skeletal Locations  

UK PubMed Central (United Kingdom)

IntroductionIrradiation of normal, non-malignant bone during cancer therapy can lead to atrophy and increased risk of fracture at several skeletal sites, particularly...Full Text Available

2010-01-01

339

Regulation of DAF-16-mediated Innate Immunity in Caenorhabditis elegans*  

UK PubMed Central (United Kingdom)

Activation of the innate immune system results in a rapid microbicidal response against microorganisms, which needs to be fine-tuned because uncontrolled immune responses can lead to infection and cancer,...Full Text Available

2009-12-18

340

Reduction of anti-malarial consumption after rapid diagnostic tests implementation in Dar es Salaam: a before-after and cluster randomized controlled study  

UK PubMed Central (United Kingdom)

BackgroundPresumptive treatment of all febrile patients with anti-malarials leads to massive over-treatment. The aim was to assess the effect of implementing malaria rapid diagnostic...Full Text Available

341

Redirection of tryptophan leads to production of low indole glucosinolate canola.  

UK PubMed Central (United Kingdom)

Cruciferous plants are known to produce over a hundred different mustard oil glycosides, which are derived from methionine, phenylalanine, or tryptophan. In oil-producing crops like Brassica napus (canola),...Full Text Available

1994-03-15

342

Reanalyses of Gulf of Mexico fisheries data: Landings can be misleading in assessments of fisheries and fisheries ecosystems  

UK PubMed Central (United Kingdom)

We used two high profile articles as cases to demonstrate that use of fishery landings data can lead to faulty interpretations about the condition of fishery ecosystems. One case uses the mean trophic...Full Text Available

2008-02-19

343

Radioprotective Effect of American Ginseng on Human Lymphocytes at 90 Minutes Postirradiation: A Study of 40 Cases  

UK PubMed Central (United Kingdom)

AbstractBackgroundIonizing radiation (IR) initiates intracellular oxidative stress through enhanced formation of reactive oxygen species (ROS) that attack DNA leading...Full Text Available

2010-05-01

344

Quantitative Analysis of Endocytosis and Turnover of Epidermal Growth Factor (EGF) and EGF Receptor  

UK PubMed Central (United Kingdom)

Binding of epidermal growth factor (EGF) to the EGF receptor (EGFR) initiates signal transduction, ultimately leading to altered gene expression. Ligand-activated EGFR is also rapidly internalized...Full Text Available

2010-03-01

345

Quality assessment of reporting of randomization, allocation concealment, and blinding in traditional chinese medicine RCTs: A review of 3159 RCTs identified from 260 systematic reviews  

UK PubMed Central (United Kingdom)

BackgroundRandomized controlled trials (RCTs) which are of poor quality tend to exaggerate the effect estimate and lead to wrong or misleading conclusions. The aim of this study...Full Text Available

346

Proteomic patterns analysis with multivariate calculations as a promising tool for prompt differentiation of early stage lung tissue with cancer and unchanged tissue material  

UK PubMed Central (United Kingdom)

BackgroundLung cancer diagnosis in tissue material with commonly used histological techniques is sometimes inconvenient and in a number of cases leads to ambiguous conclusions. Frequently...Full Text Available

347

Progesterone for the prevention of preterm birth: indications, when to initiate, efficacy and safety  

UK PubMed Central (United Kingdom)

Preterm birth is the leading cause of neonatal mortality and morbidity and long-term disability of non-anomalous infants. Previous studies have identified a prior early spontaneous preterm birth as...Full Text Available

2009-01-01

348

Problems for clinical judgement: 2. Obtaining a reliable past medical history  

UK PubMed Central (United Kingdom)

ORDINARY HUMAN REASONING MAY LEAD PATIENTS to provide an unreliable history of past experiences because of errors in comprehension, recall, evaluation and expression. Comprehension of a question may...Full Text Available

2001-03-20

349

Prevention of chain cleavage in the chemical synthesis of 2'-silylated oligoribonucleotides.  

UK PubMed Central (United Kingdom)

Strong aqueous ammonium hydroxide used to remove N-acyl protecting groups from synthetic oligoribonucleotides causes removal of some alkylsilyl protecting groups from 2'-hydroxyls and leads to chain...Full Text Available

1989-05-11

350

Preemptive analgesia: the prevention of neurogenous orofacial pain.  

UK PubMed Central (United Kingdom)

Chronic neurogenous pain is often an extremely difficult condition to manage. In the orofacial region, trauma from injury or dental procedures may lead to the development of severe neuralgic pains and...Full Text Available

1995-01-01

351

Practice Leaders Programme: Entrusting and Enabling General Practitioners to Lead Change to Improve Patient Experience  

UK PubMed Central (United Kingdom)

This program focused on practice-level service change as a means of improving patient care and developing leadership skills of 19 general practitioners (GPs) and aimed to: promote and support change...Full Text Available

2011-01-01

352

Power of grammatical evolution neural networks to detect gene-gene interactions in the presence of error  

UK PubMed Central (United Kingdom)

BackgroundWith the advent of increasingly efficient means to obtain genetic information, a great insurgence of data has resulted, leading to the need for methods for analyzing this...Full Text Available

353

Piezoelectric Properties of (1-x)(Na0.5K0.5)NbO3-xAgSbO3 Lead-Free Ceramics  

British Library Electronic Table of Contents (United Kingdom)

(1-x)(Na0.5K0.5)NbO3-xAgSbO3 lead-free piezoelectric ceramics were prepared by normal sintering. The effects of the AgSbO3 on the phase structure and piezoelectric properties of the ceramics were systematically studied. These results show that the AgSbO3-modified (K0.50Na0.50)NbO3 lead-free piezoelectric ceramics form stable solution with orthorhombic structure, and the Curie temperature and the polymorphic phase transition of the ceramics decreased with increasing AgSbO3. The result shows that the piezoelectric properties of the ceramics strongly depend on the AgSbO3. The ceramics with x=0.05 possess optimum properties (d33=192 pC/N, kp=43%, Tc=348degreeC, To-t=145degreeC, ?r632, and tan d3.5%). These results indicate that the ceramic is a promising candidate material for lead-free piezoe...

2009-01-01

354

Pharmacokinetic and dosimetric characteristics of some thallium isotopes  

International Nuclear Information System (INIS)

Pharmacokinetics is studied, radiation doses to patients when using domestic thallium-201 chloride in diagnosis of the heart ischemic disease is estimated; contribution into the total dose of thallium-201 (1.5 %), thallium-201 (0.2 %) and lead-201 + lead-203 (0.05 %) radionuclide impurities is also determined. Internal doses were estimated for a heterogeneous phantom of a standard man; the calculations were carried out using a computer. Scanning of patients which were treated with radiopharmaceuticals to be diagnosed was carried out using a whole body counter and gamma-chamber. Large intestine, kidneys and thyroid are the critical organs when using thallium-201 chloride. The highest contribution into the dose to organs and the whole body from thallium-200 and thallium-202 impurities being contained in thallium-201, doesn't exceed 8.6 %. The contribution into the dose from lead-201 and lead-203 may be ...

355

Novel Pathologic Findings Associated with Urinary Retention in a Mouse Model of Mucopolysaccharidosis Type IIIB  

UK PubMed Central (United Kingdom)

Mucopolysaccharidosis type IIIB (MPS IIIB; Sanfilippo syndrome type B) is a metabolic disorder with devastating clinical characteristics starting in early childhood and leading to premature death. A...Full Text Available

2009-04-01

356

Nonlinearity in bacterial population dynamics: Proposal for experiments for the observation of abrupt transitions in patches  

UK PubMed Central (United Kingdom)

An explicit proposal for experiments leading to abrupt transitions in spatially extended bacterial populations in a Petri dish is presented on the basis of an exact formula obtained through an analytic...Full Text Available

2008-12-02

357

New frontiers in ovarian cancer diagnosis and management.  

UK PubMed Central (United Kingdom)

Ovarian carcinoma is now the leading cause of death among women. Surgery has reached its limits, and further aggressive surgery will result in an inordinate morbidity and mortality. Ovarian carcinoma...Full Text Available

1991-03-01

358

NF-kappaB mediates the survival of human bronchial epithelial cells exposed to cigarette smoke extract  

UK PubMed Central (United Kingdom)

BackgroundWe have previously reported that low concentrations of cigarette smoke extract induce DNA damage without leading to apoptosis or necrosis in human bronchial epithelial...Full Text Available

2008-01-01

359

NASA - NASA COMPUTER ROCKET SCIENCE HELPS DEBAKEY HEART PUMP TEAM  

Science.gov (United States)

Feb 24, 2000 ... NASA computer experts have been using a supercomputer to improve the NASA/ DeBakey miniature heart assist pump, leading to on-going human ...

360

Microdamage Repair and Remodeling Requires Mechanical Loading  

UK PubMed Central (United Kingdom)

Bone remodeling is necessary to avoid microdamage accumulation, which could lead to whole-bone failure. Previous studies have shown that this bone-repair mechanism is triggered by osteocyte apoptosis....Full Text Available

2010-04-01

361

Measurement of benign prostatic hyperplasia treatment effects on male sexual function  

UK PubMed Central (United Kingdom)

Benign prostatic hyperplasia (BPH) is the leading cause of lower urinary tract symptoms among the aging male population. Epidemiological, pathophysiological and clinical studies indicate that...Full Text Available

2009-01-01

362

Low level of polymorphism in two putative NPR1 homologs in the Vitaceae family  

UK PubMed Central (United Kingdom)

BackgroundGrapevine is subjected to numerous pests and diseases resulting in the use of phytochemicals in large quantities. The will to decrease the use of phytochemicals leads to...Full Text Available

363

Long-term impact of four different strategies for delivering an on-line curriculum about herbs and other dietary supplements  

UK PubMed Central (United Kingdom)

BackgroundPrevious research has shown that internet education can lead to short-term improvements in clinicians' knowledge, confidence and communication practices. We wished to better...Full Text Available

364

Life Stress, Maternal Optimism, and Adolescent Competence in Single Mother, African American Families  

UK PubMed Central (United Kingdom)

Although research demonstrates many negative family outcomes associated with single-parent households, little is known about processes that lead to positive outcomes for these families. Using...Full Text Available

2010-08-01

365

Layered Functional Network Analysis of Gene Expression in Human Heart Failure  

UK PubMed Central (United Kingdom)

BackgroundAlthough dilated cardiomyopathy (DCM) is a leading cause of heart failure (HF), the mechanism underlying DCM is not well understood. Previously, it has been demonstrated...Full Text Available

366

Late onset muscle plasticity in the whisker pad of enucleated rats  

UK PubMed Central (United Kingdom)

Blindness leads to a major reorganization of neural pathways associated with touch. Because incoming somatosensory information influences motor output, it is plausible that motor plasticity occurs in...Full Text Available

2008-10-14

367

Knowledge and Awareness about Cervical Cancer and Its Prevention amongst Interns and Nursing Staff in Tertiary Care Hospitals in Karachi, Pakistan  

UK PubMed Central (United Kingdom)

Background and ObjectiveCervical cancer is one of the leading causes of morbidity and mortality amongst the gynecological cancers worldwide, especially in developing countries. It...Full Text Available

368

Knockdown of Bicaudal C in Zebrafish (Danio rerio) Causes Cystic Kidneys: A Nonmammalian Model of Polycystic Kidney Disease  

UK PubMed Central (United Kingdom)

Polycystic kidney disease (PKD) is one of the leading causes of end-stage renal disease in humans and is characterized by progressive cyst formation, renal enlargement, and abnormal tubular development....Full Text Available

2010-04-01

369

Integrating diverse databases into an unified analysis framework: a Galaxy approach  

UK PubMed Central (United Kingdom)

Recent technological advances have lead to the ability to generate large amounts of data for model and non-model organisms. Whereas, in the past, there have been a relatively small number of central...Full Text Available

370

Insights into Genome Plasticity and Pathogenicity of the Plant Pathogenic Bacterium Xanthomonas campestris pv. vesicatoria Revealed by the Complete Genome Sequence  

UK PubMed Central (United Kingdom)

The gram-negative plant-pathogenic bacterium Xanthomonas campestris pv. vesicatoria is the causative agent of bacterial spot disease in pepper and tomato plants, which leads to economically...Full Text Available

2005-11-01

371

Industrial emissions cause extreme urban ozone diurnal variability  

UK PubMed Central (United Kingdom)

Simulations with a regional chemical transport model show that anthropogenic emissions of volatile organic compounds and nitrogen oxides (NOx = NO + NO2) lead to a dramatic diurnal...Full Text Available

2004-04-27

372

Induction of Jasmonate Biosynthesis in Arbuscular Mycorrhizal Barley Roots12  

UK PubMed Central (United Kingdom)

Colonization of barley (Hordeum vulgare cv Salome) roots by an arbuscular mycorrhizal fungus, Glomus intraradices Schenck & Smith, leads to elevated levels...Full Text Available

2002-11-01

373

Inactivating cholecystokinin-2 receptor inhibits progastrin-dependent colonic crypt fission, proliferation, and colorectal cancer in mice  

UK PubMed Central (United Kingdom)

Hyperproliferation of the colonic epithelium, leading to expansion of colonic crypt progenitors, is a recognized risk factor for colorectal cancer. Overexpression of progastrin, a nonamidated and incompletely...Full Text Available

2009-09-01

375

Hypoglycaemia and severe plasmodium falciparum malaria among pregnant sudanese women in an area characterized by unstable malaria transmission  

UK PubMed Central (United Kingdom)

BackgroundPregnant women are more susceptible to severe Plasmodium falciparum malaria, which can lead to poor maternal and fetal outcomes. Few data exist on the...Full Text Available

376

How Missing Information in Diagnosis Can Lead to Disparities in the Clinical Encounter  

UK PubMed Central (United Kingdom)

Previous studies have documented diagnostic bias and noted that its reduction could eliminate misdiagnosis and improve mental health service delivery. Few studies have investigated clinicians'...Full Text Available

2008-11-01

377

Historical Mammal Extinction on Christmas Island (Indian Ocean) Correlates with Introduced Infectious Disease  

UK PubMed Central (United Kingdom)

It is now widely accepted that novel infectious disease can be a leading cause of serious population decline and even outright extinction in some invertebrate and vertebrate groups (e.g., amphibians)....Full Text Available

378

Hepatocyte entry leads to degradation of autoreactive CD8 T cells  

UK PubMed Central (United Kingdom)

Although most self-reactive T cells are eliminated in the thymus, mechanisms to inactivate or control T cells specific for extrathymic antigens are required and exist in the periphery. By investigating...Full Text Available

2011-10-04

379

Hazard Evaluation and Technical Assistance Report No. TA 76-100, ASARCO, East Helena, Montana.  

Science.gov (United States)

A Hazard Evaluation and Technical Assistance investigation was performed by NIOSH on February 1-4, 1977, at ASARCO, East Helena, Montana, a facility engaged in lead smelting. The survey was prompted by a request from the Regional OSHA Director in referenc...

1977-01-01

380

Hair Mercury Negatively Correlates with Calcium Pump Activity in Human Term Newborns and Their Mothers at Delivery  

UK PubMed Central (United Kingdom)

BackgroundCalcium homeostasis is a known target of several environmental toxicants including lead and mercury.ObjectiveOur goal was to determine...Full Text Available

2008-02-01

381

Glycyrrhizin as antiviral agent against Hepatitis C Virus  

UK PubMed Central (United Kingdom)

BackgroundHepatitis C virus is a major cause of chronic liver diseases which can lead to permanent liver damage, hepatocellular carcinoma and death. The presently available treatment...Full Text Available

382

Genome Sequence of Campylobacter jejuni strain 327, a strain isolated from a turkey slaughterhouse  

UK PubMed Central (United Kingdom)

Campylobacter is one of the leading causes of food-borne gastroenteritis and has a high prevalence in poultry. Campylobacter jejuni subsp. jejuni 327 is a subspecies...Full Text Available

383

Genetic Ablation of NADPH Oxidase Enhances Susceptibility to Cigarette Smoke-Induced Lung Inflammation and Emphysema in Mice  

UK PubMed Central (United Kingdom)

Cigarette smoke (CS) induces recruitment of inflammatory cells in the lungs leading to the generation of reactive oxygen species (ROS), which are involved in lung inflammation and injury. Nicotinamide...Full Text Available

2008-05-01

384

Gastrointestinal obstruction due to plaster ingestion: a case-report  

UK PubMed Central (United Kingdom)

BackgroundPlaster ingestion forming gastric bezoar is a strange way to attempt suicide and this method has not yet been reported. It may lead to a mechanical obstruction of the gut,...Full Text Available

385

Gas Turbine Blade Heat Transfer Augmentation by Impingement of Air Jets Having Various Configurations.  

Science.gov (United States)

An experimental investigation of heat transfer characteristics for various configurations of air jets impinging on the leading edge inner surface of a gas turbine blade wall is presented. Three configurations were investigated, namely a slot jet, a round ...

1970-01-01

386

Fluoride ion catalyzed alkylation of purines, pyrimidines, nucleosides and nucleotides using alky halides.  

UK PubMed Central (United Kingdom)

Alkyl halides react rapidly with purines and pyrimidines in the presence of fluoride ion. Alkylation of thymidine leads to novel dimeric nucleoside derivatives bridged through N3. Alkylation of thymidine...Full Text Available

1979-04-01

387

Fecal microRNAs as novel biomarkers for colon cancer screening  

UK PubMed Central (United Kingdom)

IntroductionColorectal cancer (CRC) is the second leading cause of cancer-related deaths, but currently available non-invasive screening programs have achieved only...Full Text Available

2010-07-01

388

Factors underlying diagnostic delay in tuberculosis patients in a rural area in Tanzania: a qualitative approach  

UK PubMed Central (United Kingdom)

BackgroundDiagnostic delay in patients with tuberculosis (TB) leads to ongoing TB transmission, higher mortality rates and increased patient and government health expenditure. Qualitative...Full Text Available

2010-12-01

389

Evolution and Optimality of Similar Neural Mechanisms for Perception and Action during Search  

UK PubMed Central (United Kingdom)

A prevailing theory proposes that the brain's two visual pathways, the ventral and dorsal, lead to differing visual processing and world representations for conscious perception than those for action....Full Text Available

2010-09-01

390

Evidence for Sub-Haplogroup H5 of Mitochondrial DNA as a Risk Factor for Late Onset Alzheimer's Disease  

UK PubMed Central (United Kingdom)

BackgroundAlzheimer's Disease (AD) is the most common neurodegenerative disease and the leading cause of dementia among senile subjects. It has been proposed that AD can be caused...Full Text Available

391

Evaluation of the Hip: History and Physical Examination  

UK PubMed Central (United Kingdom)

Examination of a painful hip is fairly concise and reliable at detecting the presence of a hip joint problem. Hip joint disorders often go undetected, leading to the development of secondary disorders....Full Text Available

2007-11-01

392

Estimation of cancer incidence and mortality attributable to alcohol drinking in china  

UK PubMed Central (United Kingdom)

BackgroundCancer constitutes a serious burden of disease worldwide and has become the second leading cause of death in China. Alcohol consumption is causally associated with the...Full Text Available

393

Equilibrium and thermodynamic parameters of single and binary mixture biosorption of lead (II) and copper (II) ions onto Pseudomonas putida: Effect of temperature  

Energy Technology Data Exchange (ETDEWEB)

The biosorption of lead (II) and copper (II) ions, single component and binary systems, by dried P. putida was investigated in a batch system. The effects of initial pH, temperature, initial single and binary mixture concentrations on the biosorption kinetics and equilibrium uptake of each component, both single and binary mixtures were investigated. The bacterial biomass exhibited the highest single and binary lead (II) and copper (II) ions uptake capacity at 25 and 30 deg. C, respectively, the initial pH value of 5.5 and at the initial metal ions concentration of 100 mg dm{sup -3}. The Freundlich and Langmuir adsorption models were used for the mathematical description of the biosorption equilibrium and isotherm constants were evaluated at different temperatures. Adsorption data were well described by the Langmuir model, although they could be modeled by the Freundlich equation. The thermodynamics constants of the adsorption process: ...

2006-07-31

394

Epignathus with Fetiform Features  

UK PubMed Central (United Kingdom)

Epignathus is an extremely rare oropharyngeal teratoma that commonly arises from the palate, leading to a high mortality (80–100%) due to airway obstruction in the neonatal period. We present...Full Text Available

2011-01-01

395

Energizing the batteries for electric cars  

Energy Technology Data Exchange (ETDEWEB)

This article reports of the nickel-metal-hydride battery and its ability to compete with the lead-acid battery in electric-powered vehicles. The topics of the article include development of the battery, the impetus for development in California environmental law, battery performance, packaging for the battery's hazardous materials, and the solid electrolyte battery.

1993-07-01

396

Electric cars and the electricity system  

Energy Technology Data Exchange (ETDEWEB)

The electric power consumption of electric cars and the demand they will pose on electric utilities are considered. The increased amount of travel will require more electric power in summer, while space heating makes larger demands in winter. This leads to nearly flat demand on electric utilities throughout the year. 5 refs.

1981-01-01

397

Efficacy of ultrasound-guided obturator nerve block in transurethral surgery  

UK PubMed Central (United Kingdom)

Background:During transurethral resection surgery (TUR), accidental stimulation of the obturator nerve can cause violent adductor contraction, leading to serious intraoperative...Full Text Available

2011-01-01

398

Effects of a growth hormone-releasing hormone antagonist on telomerase activity, oxidative stress, longevity, and aging in mice  

UK PubMed Central (United Kingdom)

Both deficiency and excess of growth hormone (GH) are associated with increased mortality and morbidity. GH replacement in otherwise healthy subjects leads to complications, whereas individuals with...Full Text Available

2010-12-21

399

Dosimetric characteristics of backscattered electrons in lead  

Energy Technology Data Exchange (ETDEWEB)

In electron beam therapy, tissue overdose due to electrons backscattered from lead has been profusely studied. To quantify this dose enhancement effect, an electron backscatter factor (EBF) wasdefined as the ratio of dose at the tissue-inhomogeneity interface with and without the scatterer present. The dependence of the EBF on energy at the scatterer surface is not well known for energies lower than 3 MeV which is the most frequent clinical situation. In this work, we have done Monte Carlo calculations with the GEANT code to study EBF in lead at this energy range. The applicability of this code and the developed procedure for dose estimation has been experimentally verified. The dependence of the EBF on the beam energy incident on the scatterer has been studied for different nominal beam energies incident at the phantom's surface. The results show a trend of increase of EBF with the beam energy incident on the scatterer between 0.5 and ...

2000-07-01

400

Disturbance of inorganic phosphate metabolism in diabetes mellitus: temporary therapeutic intervention trials  

UK PubMed Central (United Kingdom)

A paradoxical metabolic imbalance in inorganic phosphate occurs from the early onset of diabetes and may lead to a reduction of high energy phosphates and tissue hypoxia. These changes take place in...Full Text Available

401

Display of Recombinant Proteins on Bacillus subtilis Spores, Using a Coat-Associated Enzyme as the Carrier?  

UK PubMed Central (United Kingdom)

The display of proteins such as feed enzymes at the surface of bacterial spore systems has a great potential use for animal feed. Feed enzymes increase the digestibility of nutrients, leading to greater...Full Text Available

2010-09-01

402

Differential Regulation of Mitogen-Activated Protein Kinase Pathways by Acetaminophen and Its Nonhepatotoxic Regioisomer 3?-Hydroxyacetanilide in TAMH Cells  

UK PubMed Central (United Kingdom)

Acetaminophen (APAP), a widely used analgesic and antipyretic that is considered to be relatively safe at recommended doses, is the leading cause of drug-induced liver failure in the United States....Full Text Available

2010-07-01

403

Delineating Bacteriostatic and Bactericidal Targets in Mycobacteria Using IPTG Inducible Antisense Expression  

UK PubMed Central (United Kingdom)

In order to identify novel high value antibacterial targets it is desirable to delineate whether the inactivation of the target enzyme will lead to bacterial death or stasis. This knowledge is particularly...Full Text Available

404

Cystic fibrosis. 4. Abnormalities of airway epithelial function and the implications of the discovery of the cystic fibrosis gene.  

UK PubMed Central (United Kingdom)

Details of ion transporting abnormalities in cystic fibrosis airway epithelium are now known. The central hypothesis, that excessive drying of the airway surfaces is a primary event that leads to all...Full Text Available

1991-02-01

405

Customizing systemic therapy in patients with advanced non-small cell lung cancer  

UK PubMed Central (United Kingdom)

Lung cancer is the leading cause of cancer deaths worldwide. Standard chemotherapy has been shown to improve quality of life and has a modest influence on overall survival. This modest improvement in...Full Text Available

2011-07-01

406

Cryptic invasion by a non-native genotype of the common reed, Phragmites australis, into North America  

UK PubMed Central (United Kingdom)

Cryptic invasions are a largely unrecognized type of biological invasion that lead to underestimation of the total numbers and impacts of invaders because of the difficulty in detecting them. The distribution...Full Text Available

2002-02-19

407

Controlled grain boundary structures in superconductors. Final report 1 Jan 77-31 Dec 81  

Energy Technology Data Exchange (ETDEWEB)

Theoretical work supported by this grant has lead to the concept of the specific pinning force Q and the development of new methods to sum elementary interaction forces to find Q. Pinning due to changes in transition temperature or thermodynamic critical field in thin layers (e.g., a grain boundary), is greatly reduced due to the proximity effect and the stress field interaction due to the dislocations in the grain boundary has been shown to be negligible. The crystalline anisotropy (CA) and electron scattering (ES) interactions have been computed for the first time for an arbitrary boundary. Experiments on niobium bicrystals, polycrystalline niobium thin foils doped with oxygen, lead-bismuth alloy thin films and lead-bismuth alloy films in which either lead or thallium has been allowed to diffuse down the grain boundaries and out into the grains provide evidence that confirms the predictions of the ...

1982-03-01

408

Contrasting Population Structures of the Genes Encoding Ten Leading Vaccine-Candidate Antigens of the Human Malaria Parasite, Plasmodium falciparum  

UK PubMed Central (United Kingdom)

The extensive diversity of Plasmodium falciparum antigens is a major obstacle to a broadly effective malaria vaccine but population genetics has rarely been used to guide vaccine design....Full Text Available

409

Construction and Characterization of Genetically Defined aro omp Mutants of Enterotoxigenic Escherichia coli and Preliminary Studies of Safety and Immunogenicity in Humans  

UK PubMed Central (United Kingdom)

Enterotoxigenic Escherichia coli (ETEC) is a leading cause of diarrhea in travelers to countries where the disease is endemic and causes a major disease burden in the indigenous population,...Full Text Available

2001-08-01

410

Colonoscopic perforation leading to a diagnosis of Ehlers Danlos syndrome type IV: a case report and review of the literature  

UK PubMed Central (United Kingdom)

IntroductionColonoscopic perforation is a rare but serious complication of colonoscopy. Factors known to increase the risk of perforation include colonic strictures, extensive diverticulosis,...Full Text Available

411

Collapse and Restoration of MHC Class-I-Dependent Immune Privilege  

UK PubMed Central (United Kingdom)

The collapse of major histocompatiblity complex (MHC) class-I-dependent immune privilege can lead to autoimmune disease or fetal rejection. Pragmatic and instructive models are needed to clarify the...Full Text Available

2004-02-01

412

Circadian Disruption and Metabolic Disease: Findings from Animal Models  

UK PubMed Central (United Kingdom)

Social opportunities and work demands have caused humans to become increasingly active during the late evening hours, leading to a shift from the predominantly diurnal lifestyle of our ancestors...Full Text Available

2010-10-01

413

Characterization of a fatty acid and retinol binding protein orthologue from the hookworm Ancylostoma ceylanicum?  

UK PubMed Central (United Kingdom)

Hookworms, bloodfeeding intestinal nematodes, infect nearly one billion people in resource limited countries and are a leading cause of anemia and malnutrition. Like other nematodes, hookworms...Full Text Available

2009-12-01

414

Characteristics of chronic non-specific musculoskeletal pain in children and adolescents attending a rheumatology outpatients clinic: a cross-sectional study  

UK PubMed Central (United Kingdom)

BackgroundChronic non-specific musculoskeletal pain (CNSMSP) may develop in childhood and adolescence, leading to disability and reduced quality of life that continues into adulthood....Full Text Available

415

Carbon Monoxide Protects against Ventilator-induced Lung Injury via PPAR-? and Inhibition of Egr-1  

UK PubMed Central (United Kingdom)

Rationale: Ventilator-induced lung injury (VILI) leads to an unacceptably high mortality. In this regard, the antiinflammatory properties of inhaled carbon monoxide (CO) may provide...Full Text Available

2008-06-01

416

Both common and specialty mushrooms inhibit adhesion molecule expression and in vitro binding of monocytes to human aortic endothelial cells in a pro-inflammatory environment  

UK PubMed Central (United Kingdom)

BackgroundCardiovascular disease (CVD) is a leading cause of mortality in the United States as well as globally. Epidemiological studies show that regular fruit and vegetable consumption...Full Text Available

417

Blood leukocyte DNA hypomethylation and gastric cancer risk in a high-risk Polish population  

UK PubMed Central (United Kingdom)

Global hypomethylation has been shown to increase genome instability potentially leading to increased cancer risk. We determined whether global methylation in blood leukocyte DNA was associated...Full Text Available

2010-10-15

418

Basic processes in internal combustion engines. 1989  

Energy Technology Data Exchange (ETDEWEB)

This book contains 8 papers including the topics of: Spray and Flame Structure in Diesel Combustion; Experimental and Theoretical Investigations of Diesel Injection Transients; Lead-Fuel Governor System - Dual-Fuel Engine; Fuel Spray Modeling in Swirling Flows.

1989-01-01

419

Automaticity and conduction properties of bio-artificial pacemakers assessed in an in vitro monolayer model of neonatal rat ventricular myocytes  

UK PubMed Central (United Kingdom)

AimsA better understanding of the ionic mechanisms for cardiac automaticity can lead to better strategies for engineering bio-artificial pacemakers. Here, we attempted to better...Full Text Available

2010-08-01

420

Association of Thyroid Hormone Concentrations with Levels of Organochlorine Compounds in Cord Blood of Neonates  

UK PubMed Central (United Kingdom)

BackgroundThyroid hormones are important regulators of brain development. During critical periods of development, even transient disorders in thyroid hormone availability may lead...Full Text Available

2007-12-01

421

Association between a specific apolipoprotein B mutation and familial defective apolipoprotein B-100.  

UK PubMed Central (United Kingdom)

Familial defective apolipoprotein (apo) B-100 is a genetic disease that leads to hypercholesterolemia and to an increased serum concentration of low density lipoproteins that bind defectively to the...Full Text Available

1989-01-01

422

Apolipoprotein E-Mimetics Inhibit Neurodegeneration and Restore Cognitive Functions in a Transgenic Drosophila Model of Alzheimer's Disease  

UK PubMed Central (United Kingdom)

BackgroundMutations of the amyloid precursor protein gene (APP) are found in familial forms of Alzheimer's disease (AD) and some lead to the elevated production...Full Text Available

423

Angiotensin II Promotes Development of the Renal Microcirculation through AT1 Receptors  

UK PubMed Central (United Kingdom)

Pharmacologic or genetic deletion of components of the renin-angiotensin system leads to postnatal kidney injury, but the roles of these components in kidney development are unknown. To test the hypothesis...Full Text Available

2010-03-01

424

Analysis on the alterations of lens proteins by Vitex negundo in selenite cataract models  

UK PubMed Central (United Kingdom)

PurposeCataract is the leading cause of blindness and is associated with oxidative damage and protein modification in the lens. In the present study, we have employed proteomic and...Full Text Available

425

Akt pathway is hypoactivated by synergistic actions of diabetes mellitus and hypercholesterolemia resulting in advanced coronary artery disease  

UK PubMed Central (United Kingdom)

Atherosclerosis is an inflammatory process leading to enhanced cellular proliferation, apoptosis, and vasa vasorum (VV) neovascularization. While both diabetes mellitus (DM) and hypercholesterolemia...Full Text Available

2010-09-01

426

Age-Related Deterioration of Rod Vision in Mice  

UK PubMed Central (United Kingdom)

Even in healthy individuals, aging leads to deterioration in visual acuity, contrast sensitivity, visual field, and dark adaptation. Little is known about the neural mechanisms that drive the...Full Text Available

2010-08-18

427

Activation of the subventricular zone in multiple sclerosis: Evidence for early glial progenitors  

UK PubMed Central (United Kingdom)

In multiple sclerosis (MS), oligodendrocyte and myelin destruction lead to demyelination with subsequent axonal loss. Experimental demyelination in rodents has highlighted the activation of the subventricular...Full Text Available

2007-03-13

428

Activation calculations using an expanded data base  

Energy Technology Data Exchange (ETDEWEB)

Using an expanded nuclear data base, the activation of nitrogen, aluminum, iron, nickel, copper, zirconium, niobium, molybdenum, tungsten, and lead were calculated for the first wall positions of the STARFIRE and MARS conceptual fusion reactors.

1986-04-01

429

Acidizing subterranean well formations containing deposits of metal compounds  

Science.gov (United States)

Methods of acidizing a subterranean well formation, acidizing compositions, and sequestering additives for preventing the precipitation of metal compounds in the formation are described. Use of the methods and chemicals described should lead to improved formation permeability as compared to use of previous methods and chemicals. 12 claims.

1979-04-24

430

Absence of Ataxin-3 Leads to Enhanced Stress Response in C. elegans  

UK PubMed Central (United Kingdom)

Ataxin-3, the protein involved in Machado-Joseph disease, is able to bind ubiquitylated substrates and act as a deubiquitylating enzyme in vitro, and it has been involved in the modulation of protein...Full Text Available

431

A Cytogenetic Abnormality and Rare Coding Variants Identify ABCA13 as a Candidate Gene in Schizophrenia, Bipolar Disorder, and Depression  

UK PubMed Central (United Kingdom)

Schizophrenia and bipolar disorder are leading causes of morbidity across all populations, with heritability estimates of ∼80% indicating a substantial genetic component. Population genetics...Full Text Available

2009-12-11

432

A 1500-year record of lead, copper, arsenic, cadmium, zinc level in Antarctic seal hairs and sediments  

Energy Technology Data Exchange (ETDEWEB)

To reconstruct the profiles of heavy metal levels in the South Ocean ecosystem of Antarctica, the concentrations of lead (Pb), copper (Cu), arsenic (As), cadmium (Cd), and zinc (Zn) in seal hairs and lake sediments spanning the past 1500 years from Fildes Peninsula of King George Island and in weathering lake sediments from Nelson Island of West Antarctica were determined. The lead contents in the seal hairs and the weathering sediments show a sharp increase since the late 1800s, very likely due to anthropogenic contamination from modern industries. After the 1980s, the Pb content in seal hairs dropped by one-third, apparently due to the reduced usage of leaded gasoline in the Southern Hemisphere. Copper arises mainly from the weathering process, and its level may be substantially affected by climatic conditions. The concentrations of Cd, As, and Zn do not show any clear temporal trends.

2006-12-01

433

?H2AX and cancer  

UK PubMed Central (United Kingdom)

Histone H2AX phosphorylation on a serine four residues from the carboxyl terminus (producing γH2AX) is a sensitive marker for DNA double-strand breaks (DSBs). DSBs may lead to cancer...Full Text Available

2008-12-01

434

?Activation of the mitogen-activated protein kinase pathways by heat shock  

UK PubMed Central (United Kingdom)

In addition to inducing new transcriptional activities that lead within a few hours to the accumulation of heat shock proteins (Hsps), heat shock activates within minutes the major signaling transduction...Full Text Available

2002-04-01

435

27na4  

Wastenet

by American scientists, ecosystems containing a greater number of plant species, produce more biomass.This result ...to meet the increasing demand for land for farmland planted with monocultures, buildings and roads.For ...have hypothesized that greater ecological diversity (diversity of plant and animal species) leads to a greater

436

Reliability analysis of discrete event dynamic systems with Petri nets  

International Nuclear Information System (INIS)

This paper deals with dynamic reliability of embedded systems. It presents a method for deriving feared scenarios (which might lead the system to a critical situation) in Petri nets. A classical way to obtain scenarios in Petri nets is to generate the reachability graph. However, for complex systems, it leads to the state space explosion. To avoid this problem, in our approach, Petri net reachability is translated into provability of linear logic sequents. Linear logic bases are introduced and used to formally define scenarios and minimality of scenarios. These definitions allow the method to produce only pertinent scenarios. The steps of the method are described and illustrated through a landing-gear system example.

2009-11-01

437

Rechargeable zinc/manganese dioxide cell  

Energy Technology Data Exchange (ETDEWEB)

A rechargeable cell is disclosed which is characterized in the following manner. A positive electrode is formed from a manganese oxide electrode material. This manganese oxide electrode material contains a heavy metal selected from the group comprising lead, bismuth, and mixtures of lead and bismuth. The cell also contains a negative electrode of zinc. A separator is provided between the positive electrode and the negative electrode. An alkaline electrolyte consisting essentially of an alcohol and an alkaline hydroxide is also contained in the rechargeable cell in contact with both the positive electrode and the negative electrode.

1984-05-29

438

Production of superheavy elements in cold fusion reactions  

International Nuclear Information System (INIS)

The cold fusion reactions leading to superheavy elements with Z=104-116 has been discussed in our model recently [5]. Presently we shortly discuss our model and extend our consideration to fusion reactions ("8"6Kr, "8"7Rb, "8"8Sr)+"2"0"8Pb and "8"6Kr+"2"0"9Bi leading to elements with Z=118-120. The available experimental cross-section data for the reactions are well described.

2001-04-19

439

Optimal Parameter Selection of Power System Stabilizer using Genetic Algorithm  

Energy Technology Data Exchange (ETDEWEB)

In this paper, it is suggested that the selection method of optimal parameter of power system stabilizer (PSS) with robustness in low frequency oscillation for power system using real variable elitism genetic algorithm (RVEGA). The optimal parameters were selected in the case of power system stabilizer with one lead compensator, and two lead compensator. Also, the frequency responses characteristics of PSS, the system eigenvalues criterion and the dynamic characteristics were considered in the normal load and the heavy load, which proved usefulness of RVEGA compare with Yu's compensator design theory. (author). 20 refs., 15 figs., 8 tabs.

1999-06-01

440

Open descendants in conformal field theory  

International Nuclear Information System (INIS)

Open descendants extend conformal field theory to unoriented surfaces with boundaries. The construction rests on two types of generalizations of the fusion algebra. The first is needed even in the relatively simple case of diagonal models. It leads to a new tensor that satisfies the fusion algebra, but whose entries are signed integers. The second is needed when dealing with non-diagonal models, where Cardy's ansatz does not apply. It leads to a new tensor with positive integer entries, that satisfies a set of polynomial equations and encodes the classification of the allowed boundary operators. (orig.).

1995-12-01

441

Loss of flow accident analysis of a water-cooled fusion reactor  

International Nuclear Information System (INIS)

Within the APROS simulation environment we have built a thermo-hydraulic model of a conceptual fusion power plant which is water cooled and uses lithium-lead for tritium breeding. For the safety assessment of this design we have studied an accident sequence which starts from a loss or coolant flow then leads to first wall breach and pressurisation of the vacuum vessel. Simulations have revealed strong pressure transients which can be alleviated by design changes. One goal is to verify the adequacy of the containment design: it remains intact at least 14 h without any mitigating efforts. Estimates for radioactive releases are obtained. (author)

2003-08-25

442

Lithium-lead/water reaction experiments and analysis  

Energy Technology Data Exchange (ETDEWEB)

An experiment has been performed to investigate the chemical reaction between the liquid phases of the eutectic lithium-lead (Li/sub 17/Pb/sub 83/) and water. The reactants and products were constrained within a closed reaction vessel, allowing the extent of reaction to be determined from the partial pressure of the hydrogen reaction product. The data from the tests showed that the extent of reaction did not depend upon the water temperature. The data also indicated that the extent of reaction passed through a maximum as the initial liquid metal temperature was varied from 350 to 500 C, and a model was developed to explain this behavior. 11 refs., 3 figs.

1988-01-01

443

Ion motion and finite temperature effect on relativistic strong plasma waves  

CERN Document Server

The influence of motion of ions and electron temperature on nonlinear one-dimensional plasma waves with velocity close to the speed of light in vacuum investigated. It is shown that although the wavebreaking field weakly depends on mass of ions, the nonlinear relativistic wavelength essentially changes. The nonlinearity leads to the increase of the strong plasma wavelength, while the motion of ions leads to the decrease of the wavelength. Both hydrodynamic approach and kinetic one, based on Vlasov-Poisson equations, are used to investigate the relativistic strong plasma waves in a warm plasma. The existence of relativistic solitons in a thermal plasma is predicted.

1998-01-01

444

Investigating Biochar: from Source to Sink (Overview - Research)  

Wastenet

...Investigating Biochar: from Source to Sink (Overview - Research) The Sustainable Agriculture Flagship is leading national collaborative research analysing the properties ...and potential of a variety of biochars to improve soil health and sequester carbon. The Sustainable Agriculture Flagship is leading national collaborative research ...analysing the properties and potential of a variety of biochars to improve soil health and sequester carbon. Biochar, sustainable agriculture, soil,...carbon, SAF, pyrolysis, fertiliser, biochar, soil types, greenhouse gas, herbicide, pesticide, bioenergy, soil science, carbon-rich solid, ...

445

Inclusive photoproduction of D{sup *{+-}} mesons at next-to-leading order in the general-mass variable-flavor-number scheme  

Energy Technology Data Exchange (ETDEWEB)

We discuss the inclusive production of D{sup *{+-}} mesons in {gamma}p collisions at DESY HERA, based on a calculation at next-to-leading order in the general-mass variable-flavor-number scheme. In this approach, MS subtraction is applied in such a way that large logarithmic corrections are resummed in universal parton distribution and fragmentation functions and finite mass terms are taken into account. We present detailed numerical results for a comparison with data obtained at HERA and discuss various sources of theoretical uncertainties. (orig.)

2009-02-15

446

Feynman scaling violation due to baryon number diffusion in rapidity space  

CERN Document Server

A significant asymmetry in baryon/antibaryon yields in the central region of high energy collisions is observed when the initial state has non-zero baryon charge. This asymmetry is connected with the possibility of a baryon charge diffusion in rapidity space. Evidently, such a diffusion should decrease the baryon charge in the fragmentation region leading to the corresponding decrease of the multiplicity of leading baryons. As a result, a new mechanism for Feynman scaling violation in the fragmentation region is obtained. We present the quantitative predictions for the Feynman scaling violation at LHC energies and even at highier energies that can be important for cosmic ray physics.

2011-01-01

447

Exploratory battery technology development and testing report for 1989  

Energy Technology Data Exchange (ETDEWEB)

Sandia National Laboratories, Albuquerque, has been designated as Lead Center for the Exploratory Battery Technology Development and Testing Project, which is sponsored by the US Department of Energy's Office of Energy Storage and Distribution. In this capacity, Sandia is responsible for the engineering development of advanced rechargeable batteries for both mobile and stationary energy storage applications. This report details the technical achievements realized in pursuit of the Lead Center's goals during calendar year 1989. 4 refs., 84 figs., 18 tabs.

1990-12-01

448

Electron beam therapy in carcinoma of the buccal mucosa  

Energy Technology Data Exchange (ETDEWEB)

Electron beam therapy has often been used for radiation therapy of carcinomas of the buccal mucosa, though side effects, including stomatitis and dermatitis, are known to exist. We experimented using the additional back scatter and transit with the phantom under a lead plate within the irradiation field, in order to better focus the dose on the target volume moreover, we fabricated a mouthpiece fitted with a lead plate shaped to the target volume, and with respect to the influence of the mouthpiece on stomatitis and dermatitis, obtained good clinical results. (author).

1990-10-01

449

Electron beam therapy in carcinoma of the buccal mucosa  

International Nuclear Information System (INIS)

Electron beam therapy has often been used for radiation therapy of carcinomas of the buccal mucosa, though side effects, including stomatitis and dermatitis, are known to exist. We experimented using the additional back scatter and transit with the phantom under a lead plate within the irradiation field, in order to better focus the dose on the target volume moreover, we fabricated a mouthpiece fitted with a lead plate shaped to the target volume, and with respect to the influence of the mouthpiece on stomatitis and dermatitis, obtained good clinical results. (author).

450

Common envelope evolution  

British Library Electronic Table of Contents (United Kingdom)

The common envelope phase of binary star evolution plays a central role in many evolutionary pathways leading to the formation of compact objects in short period systems. Using three dimensional hydrodynamical computations, we review the major features of this evolutionary phase, focusing on the conditions that lead to the successful ejection of the envelope and, hence, survival of the system as a post common envelope binary. Future hydrodynamical calculations at high spatial resolution are required to delineate the regime in parameter space for which systems survive as compact binary systems from those for which the two components of the system merge into a single rapidly rotating star. Recent algorithmic developments will facilitate the attainment of this goal.

2010-01-01

451

Comments on EPA's (Environmental Protection Agency's) effluent-limitation guidelines covering the lead-acid battery manufacturing industry  

Energy Technology Data Exchange (ETDEWEB)

Lead-acid batteries, one of eight types, account for about 70% of annualized control costs facing the battery manufacturing industry as a result of EPA's guidelines. This report is the industry's response. It makes counter recommendations for effluent limitations, discusses selected control technologies and effluent limitations, makes control cost estimates, and provides an economic impact analysis and a benefits effectiveness analysis.

1984-01-01

452

Coherent correlation enhancement of outer shell photoionization cross sections of alkali-like ions  

Energy Technology Data Exchange (ETDEWEB)

An alkali-like ion interaction with inner electrons of an alkali-like ion leads to a significant increase in the photoionization cross section of the outer s electron. This occurs not only for ground-state ions with one s electron in the outer shell, but also when the outer s electron is in an excited state. The reason for this amplification, in addition to coherent enhancement in summing of the correlation amplitudes, is that the zero in the direct amplitude occurs below threshold. This leads to a constructive interference with the correlation amplitude above the photoionization threshold, in contrast to a destructive interference in the case of a neutral atom with the same electronic configuration, for which the zero occurs above threshold. Results of this research were published.

1995-08-01

453

Beginning Scala  

CERN Document Server

The open source Scala language is a Java--based dynamic scripting, functional programming language. Moreover, this highly scalable scripting language lends itself well to building Cloud--based/deliverable Software as a Service (SaaS) online applications. Written by Lift Scala web framework founder and lead Dave Pollak, Beginning Scala takes a down--to--earth approach to teaching Scala that leads you through simple examples that can be combined to build complex, scalable systems and applications. This book introduces you to the Scala programming language and then guides you through Scala constr

2009-01-01

454

An examination of cyclic variations in a dual fuel engine  

Energy Technology Data Exchange (ETDEWEB)

The paper considers the cyclic variations in performance parameters of a dual fuel engine fuelled with methane. It is shown that such an engine does display cyclic variations that are greater than the corresponding diesel operation, yet smaller than comparable spark ignition operation. The extent of cyclic variation in peak cylinder pressure and ignition delay increases, for any power output, as the pilot diesel quantity is reduced and the extent of gas substitution is increased. The use of extremely small pilots in the unmodified engine can lead to erratic engine performance. Greater cyclic variations are associated with low lead rather than high load operation.

1988-01-01

455

Activation method for determination of Pb, La, Zr and Ti macrocomponents in lead-lanthanum zirconate-titanate materials on a neutron generator  

International Nuclear Information System (INIS)

Instrumental neutron activation analysis is used for simultaneously determination of macrocomponents in ferroelectric materials LLZT. Pb, Zr, Ti have been determined by "2"0"3Pb, "8"9Zr and "4"8Sc nuclides created by fast neutron (14.5 MeV) activation. Application of paraffine as neutron moderator and reflector allows to simultaneously determine lanthanum by "1"4"0La nuclide. It has been shown that zirconium, titanium and lanthanum can be determined with the accuracy of #+-#0.1 mas. % and lead - #+-#0.7 mas. %.

456

Acoustic response of piezoelectric lead-zirconate-titanate to a 400MeV/n xenon beam  

Energy Technology Data Exchange (ETDEWEB)

Characteristics of lead-zirconate-titanate (PZT) elements were studied by directly irradiating them with a 400 MeV/n Xe beam. The elements were sensitive to 10{sup 4} Xe ions and their output amplitudes were proportional to the beam intensity. An ensemble of those output amplitudes displayed a Bragg-curve-like response towards the range of 400 MeV/n Xe ion. We discuss the potential of PZT elements as a radiation detector and their application to high-intensity and high-energy detectors. (author)

2003-03-01

457

Stress corrosion cracking susceptibility of alloy 800  

Energy Technology Data Exchange (ETDEWEB)

Steam generators (SGs) in PWRs and CANDUs are designed for at least a 30-year operating life. However, in the 15-25 years that SGs tubed with Alloy 600 have operated commercially, they have experienced reduced reliability, mainly due to SG tubing degradation. One of the degradation mechanisms that Alloy 600 SG tubing has suffered from is lead-induced stress corrosion cracking (PbSCC) in AVT and near-neutral SG environments. In contrast to Alloy 600 tubing, test data obtained in high temperature water indicate that Alloy 800 is resistant to cracking by lead and lead compounds. For Alloy 800 (cold worked, shot peened), the most aggressive environment is reported to be alkaline with minor concentration of PbO (80 ppm). Work by Max Helie et al. also concluded that Alloy 800 is not sensitive to lead assisted SCC for pH values close to neutrality, whereas it could be affected in high alkaline conditions. The ...

2002-07-01

458

Stress corrosion cracking susceptibility of alloy 800  

International Nuclear Information System (INIS)

Steam generators (SGs) in PWRs and CANDUs are designed for at least a 30-year operating life. However, in the 15-25 years that SGs tubed with Alloy 600 have operated commercially, they have experienced reduced reliability, mainly due to SG tubing degradation. One of the degradation mechanisms that Alloy 600 SG tubing has suffered from is lead-induced stress corrosion cracking (PbSCC) in AVT and near-neutral SG environments. In contrast to Alloy 600 tubing, test data obtained in high temperature water indicate that Alloy 800 is resistant to cracking by lead and lead compounds. For Alloy 800 (cold worked, shot peened), the most aggressive environment is reported to be alkaline with minor concentration of PbO (80 ppm). Work by Max Helie et al. also concluded that Alloy 800 is not sensitive to lead assisted SCC for pH values close to neutrality, whereas it could be affected in high alkaline conditions. The ...

2002-05-05

459

Present status of biological effects of toxic metals in the environment: lead, cadmium, and manganese  

Energy Technology Data Exchange (ETDEWEB)

The number of reports concerning the chemical toxicology of metals which are released in the environment by natural as well as anthropogenic sources, have been increasing constantly. Lead, cadmium, and manganese have found a variety of uses in industry, craft, and agriculture owing to their physical and chemical properties. The environmental burden of heavy metals has been rising substantially by smelter emission in air and waste sewage in water. Further, organic compounds of lead and manganese used as antiknock substances in gasoline are emitted into the atmosphere by automobile exhaustion. Such environmental contamination of air, water, soil, and food is a serious threat to all living kinds. Although these metals are known to produce their toxic effects on a variety of body systems, much emphasis has been placed on their effects on the nervous system owing to apparent association of relatively low or ...

1984-08-01

460

Omaha childhood blood lead and environmental lead: a linear total exposure model  

Energy Technology Data Exchange (ETDEWEB)

The majority of experimental and population studies of blood lead (PbB) and environmental lead, including the Omaha study, have utilized the Goldsmith-Hexter log-log or power function model. Comparison was made of the log-log model and a linear model of total exposure as they described the Omaha Study of 1074 PbBs from children ages 1-18 years as related to air (PbA), soil (PbS), and housedust (PbHD) lead. The data fit of the linear model was statistically equivalent to the power model and the predicted curves were biologically more plausible. The linear model avoids the mathematical limitations of the power model which predicts PbB zero at PbA zero. From the Omaha data, this model, ln PbB = ln (..beta../sub 0/ + B/sub 1/ PbA + B/sub 2/ PbS + ..beta../sub 3/ PbHD) predicts that PbB increases 1.92 ..mu..g/dl as PbA increases 1.0 ..mu..g/m/sup 3/. Since PbS and PbHD increase with PbA, however, the increases in total exposure ...

1984-10-01

461

Land Disposal Restrictions Treatment Standards: Compliance Strategies for Four Types of Mixed Wastes  

International Nuclear Information System (INIS)

This paper describes the unique challenges involved in achieving compliance with the Resource Conservation and Recovery Act (Public Law 94-580) Land Disposal Restrictions (LDR) treatment standards for four types of mixed wastes generated throughout the U.S. Department of Energy (DOE) complex: (1) radioactively contaminated lead acid batteries; (2) radioactively contaminated cadmium-, mercury-, and silver-containing batteries; (3) mercury-bearing mixed wastes; and (4) radioactive lead solids. For each of these mixed waste types, the paper identifies the strategy pursued by DOE's Office of Pollution Prevention and Resource Conservation Policy and Guidance (EH-43) in coordination with other DOE elements and the U.S. Environmental Protection Agency (EPA) to meet the compliance challenge. Specifically, a regulatory interpretation was obtained from EPA agreeing that the LDR treatment standard for wastes in the D008 'Radioactive ...

6000-01-01

462

Wind tunnel test on a straight wing vertical-axis wind turbine with attachment on blade surface  

Energy Technology Data Exchange (ETDEWEB)

There is a renewed interest in straight wing vertical axis wind turbines (SW-VAWT) which are usually installed on the roofs of high buildings in cities, urban areas and high mountain areas for independent electric power supply. SW-VAWTs have the advantages of simple design and low cost, as well as wind direction independence compared to the horizontal system. However, when SW-VAWTs are installed in cold regions, ice, snow and other attachments can affect its performance. In this study, clay was attached to the leading edge of the blade surface to determine how the performance of SW-VAWTs are affected by the mechanism of icing. Wind tunnel tests were used to study the rotational performance and power performance of the turbine blades. Icing prevention was also investigated. The attachment of clay on the leading edge of blade surface made the rotational performance of the SW-VAWT worse. The attachment of clay on the leading ...

2008-07-01

463

Theoretical Support for the Hydrodynamic Mechanism of Pulsar Kicks  

CERN Document Server

The collapse of a massive star's core, followed by a neutrino-driven, asymmetric supernova explosion, can naturally lead to pulsar recoils and neutron star kicks. Here, we present a two-dimensional, radiation-hydrodynamic simulation in which core collapse leads to significant acceleration of a fully-formed, nascent neutron star (NS) via an induced, neutrino-driven explosion. During the explosion, a ~10% anisotropy in the low-mass, high-velocity ejecta lead to recoil of the high-mass neutron star. At the end of our simulation, the NS has achieved a velocity of ~150 km s$^{-1}$ and is accelerating at ~350 km s$^{-2}$, but has yet to reach the ballistic regime. The recoil is due almost entirely to hydrodynamical processes, with anisotropic neutrino emission contributing less than 2% to the overall kick magnitude. Since the observed distribution of neutron star kick velocities peaks at ~300-400 km s$^{-1}$, recoil due to ...

2010-01-01

464

The phase shifts leading to the broadening and shift of spectral lines  

International Nuclear Information System (INIS)

The classical theory of collisional broadening and shift parameters (?, ?) of an isolated spectral line was used to obtain simple analytical formulas for calculating both ? and ?. These formulas were obtained on the assumption that the short range interaction is effective only in the broadening while the long range is effective in the shift of the spectral line. These parameters ? and ? depend on the limiting phase shifts responsible for broadening ?b and shift ??. It was found that the values of ?b and ?? are not equal to each other as was proposed by Weisskopf ?b=??=1. The maximum and average values of ?b (?bmax, ?bav) and ?? (??max, ??av) were obtained by numerical evaluation, using different inverse power potentials. By introducing these parameters into the approximated formulas for ? and ? using Van der Waals and Lennard-Jones potential, it was found that the results of calculations for (? and ?) with different atomic transitions perturbed by different inert gases are in close ...

2009-02-01

465

Radiotracer study of the preatomization behavior of lead in the graphite furnace  

Energy Technology Data Exchange (ETDEWEB)

The behavior of lead in the graphite furnace during the individual steps of the temperature program was investigated by means of /sup 203/Pb as a radiotracer. The matrix systems include HCl and HNO/sub 3/ solutions, 1% NaCl solution, blood, serum, urine, and the solid samples bovine liver and orchard leaves. Without matrix modificaton, a pyrolysis temperature of up to 500/sup 0/C can be used for all samples. Significant stabilization effects can be achieved in the preatomization steps by using NH/sub 4/H/sub 2/PO/sub 4/ and ammonia as matrix modifiers and by addition of hydrogen to the flowing argon gas. It was found that the use of a L'vov platform also helps to eliminate the matrix effects. With respect to lead stabilization and elimination of matrix effects, optimum experimental conditions are achieved by simultaneous use of a L'vov platform and NH/sub 4/H/sub 2/PO/sub 4/ as the matrix modifier. 34 references, 5 figures, 1 ...

1985-01-01

466

Radiotracer study of the preatomization behavior of lead in the graphite furnace  

International Nuclear Information System (INIS)

The behavior of lead in the graphite furnace during the individual steps of the temperature program was investigated by means of "2"0"3Pb as a radiotracer. The matrix systems include HCl and HNO_3 solutions, 1% NaCl solution, blood, serum, urine, and the solid samples bovine liver and orchard leaves. Without matrix modificaton, a pyrolysis temperature of up to 500"0C can be used for all samples. Significant stabilization effects can be achieved in the preatomization steps by using NH_4H_2PO_4 and ammonia as matrix modifiers and by addition of hydrogen to the flowing argon gas. It was found that the use of a L'vov platform also helps to eliminate the matrix effects. With respect to lead stabilization and elimination of matrix effects, optimum experimental conditions are achieved by simultaneous use of a L'vov platform and NH_4H_2PO_4 as the matrix modifier. 34 references, 5 figures, 1 table.

467

Lifetime modelling of lead acid batteries  

Energy Technology Data Exchange (ETDEWEB)

The performance and lifetime of energy storage in batteries are an important part of many renewable based energy systems. Not only do batteries impact on the system performance but they are also a significant expenditure when considering the whole life cycle costs. Poor prediction of lifetime can, therefore, lead to uncertainty in the viability of the system in the long term. This report details the work undertaken to investigate and develop two different battery life prediction methodologies with specific reference to their use in hybrid renewable energy systems. Alongside this, results from battery tests designed to exercise batteries in similar modes to those that they experience in hybrid systems have also been analysed. These have yielded battery specific parameters for use in the prediction software and the first results in the validation process of the software are also given. This work has been part of the European Union Benchmarking research project ...

2005-04-01

468

Intestinal accumulation of lead salts and milk lead by suckling rats  

International Nuclear Information System (INIS)

Absorption of lead is known to be enhanced during infancy. In this study, the sites of intestinal accumulation of Pb by suckling rats have been determined under various conditions using "2"0"3Pb as a tracer. When "2"0"3Pb was administered intragastrically (IG) as a soluble salt, accumulation occurred primarily in the duodenum, regardless of dose and vehicle. In contrast, when rat pups suckled from a dam which had received "2"0"3Pb, the only region of the small intestine showing accumulation of radioactivity was the ileum. To confirm that these differences were not related to the route of administration, rat milk was labeled with "2"0"3Pb and was then used for IG administration. Once again, accumulation (4 hr post-administration) was confined to the ileum. When the dose was increased 10-fold, milk Pb displayed some accumulation in duodenal tissue, but very much less than that of soluble Pb at the same time and dosage. At 20 hr postadministration, there was ...

469

Influence of 2,3-dimercaptosuccinic acid on gastrointestinal lead absorption and whole-body lead retention  

International Nuclear Information System (INIS)

2,3-Dimercaptosuccinic acid (DMSA) is a new orally active heavy metal chelator for the treatment of childhood Pb intoxication on an outpatient basis. The influence of DMSA, as well as other chelating agents, on gastrointestinal 203Pb absorption and whole-body "2"0"3Pb retention was examined. Groups of Sprague-Dawley rats (230-260 g) were gavaged with a solution containing approximately 25 mg/kg Pb [as Pb(NO_3)2] plus 15 microCi "2"0"3Pb. Some groups were then immediately given 0.11 mmol/kg of either DMSA, CaNa2EDTA, D-penicillamine, or BAL by oral gavage, while other groups received the same drugs by ip injection. Control groups received solutions of the drug vehicles po or ip. Whole-body Pb retention and gastrointestinal Pb absorption (whole body retention + urinary Pb excretion) were significantly decreased in rats that received DMSA po. This finding implies that the use of DMSA to treat childhood lead intoxication on an outpatient basis is not associated with a ...

470

Four pion decay modes of the f{sub 0}(1500) resonance; Modes de desintegration de la resonance f{sub 0}(1500) en 4 pions  

Energy Technology Data Exchange (ETDEWEB)

We investigate the two-body decay modes {rho}{rho}, {pi}{pi}{sup *} (1300) and {sigma}{sigma} of the f{sub 0}(1500), all leading to the four pion decay channel, in a three-state mixing scheme, where the f{sub 0}(1500) is a mixture of the lowest lying scalar glueball with the nearby isoscalar states of the 0{sup ++}Q Q-bar nonet. In the leading order of this scheme, the decay mechanism of the f{sub 0}(1500) proceeds dominantly via its quarkonium components, which can be described in the framework of the {sup 3}P{sub 0} pair creation model. We predict the hierarchy of decay branching ratios B with B({rho}{rho}) {>=} B({pi}{pi}) {>=} B({sigma}{sigma}) > B({pi}{pi}{sup *}), providing a key signature of the proposed mixing scheme in this leading order approach. (authors)

1999-10-01

471

Formation of the Neutron Donor C13 in AGB Stars by Overshoot and Rotation  

CERN Document Server

(abridged) Observations clearly show that low-mass AGB stars can provide a nucleosynthesis site of the s-process. Recent stellar evolution models indicate that radiative burning of C13 between thermal pulses in low-mass AGB stars may indeed provide the needed neutrons. Some mixing between the proton-rich envelope and the carbon-rich core may lead to the production of C13. However, the responsible physical mechanism is not yet unambiguously identified. We present stellar model calculations with overshoot and rotation. Overshoot, with a time-dependent and exponentially decaying efficiency, leads to a partial mixture of protons and C12 during the third dredge-up. According to the depth-dependent ratio of protons and C12, a small C13-pocket forms underneath a N14-rich layer. Overshoot does not allow for any mixing during the interpulse phase. Rotation introduces mixing driven by large angular velocity gradients which form at the envelope-core ...

2000-01-01

472

Entropy, confinement, and chiral symmetry breaking  

CERN Document Server

This paper studies the way in which confinement leads to chiral symmetry breaking (CSB) through a gap equation. We argue that entropic effects cut off infrared singularities in the standard confining effective propagator $1/p^4$, which should be replaced by $1/(p^2+m^2)^2$ for a finite mass $m\\sim K_F/M(0)$ [$M(0)$ is the zero-momentum value of the running quark mass]. Extension of an old calculation of the author yields a specific estimate for $m$. This cutoff propagator shows semi-quantitatively two critical properties of confinement: 1) a negative contribution to the confining potential coming from entropic forces; 2) an infrared cutoff required by gauge invariance and CSB itself. Entropic effects lead to a proliferation of pion branches and a $\\bar{q}q$ condensate, and contribute a negative term $\\sim -K_F/M(0)$ to the effective pion Hamiltonian allowing for a massless pion in the presence of positive kinetic energy and string energy. ...

2010-01-01

473

Development of transition metal semiconductors for photoelectrolysis of water. Final report  

Energy Technology Data Exchange (ETDEWEB)

This report discusses the development of transition metal oxide semiconductors for photoelectrolysis of water. More specifically, it involves preparation of TiO/sub 2/ films by sputtering and evaluating their physicochemical characteristics primarily as they relate to the behaviour of the films as photoanodes. Impedance, photoelectrochemical, and photoconduction properties of TiO/sub 2/ films sputtered in pure O/sub 2/ onto heated substrates have been determined as a function of O/sub 2/ pressure during sputtering, film thickness, Pt overcoating, and cathodic treatment. The capacitance data before cathodic treatment are of the form expected. The capacitance is essentially independent of potential, while for potentials increasingly cathodic of this value, the capacitance increases very rapidly. Cathodic treatment alters the impedance characteristics of the films but leads to either no detectible change in their photoelectrochemical properties or to an increase in ...

1981-03-27

474

Conceptual design of a medium scale lead-bismuth cooled fast reactor  

International Nuclear Information System (INIS)

To seek for a promising concept of a heavy liquid metal coolant (HLMC) fast reactor plant, Japan Nuclear Cycle Development Institute and the electric utilities conducted conceptual design study on various types of plant concepts and compared these concepts based on technical feasibility and economical perspective. A comparative design study is performed on Lead-Bismuth cooled reactors with forced and natural convection cooling. Eliminating an intermediate cooling system makes the heat transport system simple and can decrease the amount of the weight of NSSS. Based on the estimation of the amount materials, the plant internal load etc., a construction cost of these plants are evaluated approximately 2/3 times of that of LWRs at present. And, the nitride fuel makes breeding ratio of 1.2 with 150 GWd/t of burnup. The results of unprotected event analyses such as UTOP and ULOF show that both of concepts have possible features to withstand unprotected events due to ...

2003-09-15

475

Complexation study on no-carrier-added astatine with insulin: A candidate radiopharmaceutical  

Energy Technology Data Exchange (ETDEWEB)

No-carrier-added astatine radionuclides produced in the {sup 7}Li-irradiated lead matrix were separated from bulk lead nitrate target by complexing At with insulin, followed by dialysis. The method offers simultaneous separation of At from lead as well as its complexation with insulin. The At-insulin complex might be a potential radiopharmaceutical in the treatment of hepatocellular carcinoma. The stability of At-insulin complex was checked by dialysis against deionized water and Ringer lactate (RL) solution. It has been found that the half-life of At-insulin complex is about {approx}12 h, when dialyzed against deionized water and is only 6 h, when dialyzed against RL solution having the same composition as blood serum. The 6 h half-life of this Insulin-At complex is perfect for killing cancer cells from external cell surfaces as the half-life of internalization of insulin molecule inside the cell is 7-12 h.

2008-12-15

476

Complexation study on no-carrier-added astatine with insulin: A candidate radiopharmaceutical  

International Nuclear Information System (INIS)

No-carrier-added astatine radionuclides produced in the "7Li-irradiated lead matrix were separated from bulk lead nitrate target by complexing At with insulin, followed by dialysis. The method offers simultaneous separation of At from lead as well as its complexation with insulin. The At-insulin complex might be a potential radiopharmaceutical in the treatment of hepatocellular carcinoma. The stability of At-insulin complex was checked by dialysis against deionized water and Ringer lactate (RL) solution. It has been found that the half-life of At-insulin complex is about #approx#12 h, when dialyzed against deionized water and is only 6 h, when dialyzed against RL solution having the same composition as blood serum. The 6 h half-life of this Insulin-At complex is perfect for killing cancer cells from external cell surfaces as the half-life of internalization of insulin molecule inside the cell is 7-12 h.

2008-12-01

477

Apoferritin Templated Synthesis of Metal Phosphate Nanoparticle Labels for Electrochemical Immunoassay  

Energy Technology Data Exchange (ETDEWEB)

W have introduced template-synthesized metal phosphate nanoparticle labels for electrochemical immunoassay. Such use of an apoferritin template offers a simple and convenient route to prepare metallic nanoparticle labels for electrochemical immunoassays and avoid the complicated and time-consuming nanoparticle synthesis process (QD synthesis). Releasing metal ions from metal phosphate in an acetate buffer (pH 4.6) eliminates the harsh condition in the traditional metallic nanoparticle dissolution (e.g., strong acid dissolution of QDs and gold nanoparticles). This method is ultrasensitive and its DL is low to 77fM. The simultaneous detection of multiple protein targets is easily performed by using different metal phosphate nanoparticle labels (cadmium phosphate and lead phosphate). This approach can be extended to prepare multiple metal (such as zinc, lead, cadmium, copper, indium, gold, silver) phosphate nanoparticle labels or hybrid metal ...

2006-08-29

478

Alpha radiation sources in low alpha materials and implications for low alpha materials refinement  

Energy Technology Data Exchange (ETDEWEB)

Traditionally wafer bumps are made from Pb containing solders. Over 20 years ago IBM recognized that {sup 210}Pb has a decay chain resulting in a 5.4 MeV alpha particle that induces soft errors. A variety of efforts to produce and characterize low alpha Pb ensued. Work at Honeywell over the past several years has shown that low alpha lead activity does not follow the decay signature predicted from {sup 210}Pb secular equilibrium. Data are presented indicating that smelting has a minimal effect on {sup 210}Pb/{sup 210}Po secular equilibrium and that other trace radionuclides are the alpha source. The implications of these data to possible alpha emitter sources in lead free solders are discussed, along with a method developed by Honeywell to remove alpha emitters from lead free solder components.

2004-09-01

479

Toward unifying the description of meson and baryon properties  

Science.gov (United States)

We present a Poincare covariant Faddeev equation, which enables the simultaneous prediction of meson and baryon observables using the leading order in a truncation of the Dyson-Schwinger equations that can systematically be improved. The solution describes a nucleon's dressed-quark core. The evolution of the nucleon mass with current-quark mass is discussed. A nucleon-photon current, which can produce nucleon form factors with realistic Q{sup 2} evolution, is described. Axial-vector diquark correlations lead to a neutron Dirac form factor that is negative, with r{sub 1}{sup nu}>r{sub 1}{sup nd}. The proton electric-magnetic form factor ratio falls with increasing Q{sup 2}.

2009-01-15

480

The in vivo measurement of radiocaesium activity in broiler chickens  

Energy Technology Data Exchange (ETDEWEB)

Contamination of certain areas of Europe with radiocaesium from the Chernobyl accident led to a higher {sup 137}Cs accumulation (i.e. 300-600 Bq kg{sup -1}) in grain and to potential post-accident contamination of broiler chickens. In future, such contamination may require a simple determination of the {sup 137}Cs activity concentration in broiler chicken meat which would lead to measures for preventing the recommended limits of radionuclide contamination of the meat for human consumption from being exceeded. This paper describes the development of a rapid method for the in vivo monitoring of the broiler chicken using a lead-shielded sodium iodide detector. The method enables simply fixed live chicken to be monitored, the results showing a good correlation (R{sup 2}=0.98) with measurements of meat from chicken previously monitored in vivo prior to slaughter.

2000-05-01

481

The #alpha#_s"3 corrections to the Bjorken sum rule for polarized electroproduction and to the Gross-Llewellyn Smith sum rule  

International Nuclear Information System (INIS)

We have computed the next-next-to-leading order QCD corrections to the Gross-Llewellyn Smith sum rule for deep inelastic neutrino-nucleon scattering and to the Bjorken sum rule for polarized electron-nucleon scattering. This involved the proper treatment of #gamma#_5 inside the loop integrals within dimensional regularization. We find that the difference between the two sum rules are entirely due to a class of six three-loop graphs and is of the order of 1% of the leading QCD term (O(#alpha#_s)). Hence the Q"2 behavior of both sum rules should be nearly the same if the physics is described adequately by the lower order terms of perturbative QCD. (orig.).

482

Strong-Weak Coupling Duality in Quantum Mechanics  

CERN Document Server

We present a strong-weak coupling duality for quantum mechanical potentials. Similarly to what happens in quantum field theory, it relates two problems with inverse couplings, leading to a mapping of the strong coupling regime into the weak one, giving information from the nonperturbative region of the parameters space. It can be used to solve exactly power-type potentials and to extract deep information about the energy spectra of polynomial ones. We present a strong-weak coupling duality for quantum mechanical potentials. Similarly to what happens in quantum field theory, it relates two problems with inverse couplings, leading to a mapping of the strong coupling regime into the weak one, giving information from the nonperturbative region of the parameters space. It can be used to solve exactly power-type potentials and to extract deep information about the energy spectra of polynomial ones.

1996-01-01

483

Separation of /sup 203/Pb by ion-exchange chromatography on Chelex 100 after production of /sup 203/Pb by the Pb(p,xn)/sup 203/Bi/sup EC. beta. +/ -> /sup 203/Pb nuclear reaction  

Energy Technology Data Exchange (ETDEWEB)

Bismuth radioisotopes, produced by 50-MeV proton bombardment of a lead target in a cyclotron, are separated from the lead target material by ion-exchange chromatography on a column containing 5.0 ml of Chelex 100. After a decay period of 24 hr, the /sup 203/Pb formed in situ is eluted from the column and then separated from /sup 200/Tl and /sup 201/Tl on a second ion-exchange column containing 0.5 ml of Chelex 100. Separations are sharp and carrier-free /sup 203/Pb is obtained.

1989-04-01

484

Production of {sup 62}Zn, {sup 65}Zn and {sup 203}Pb radioisotopes for studying the transport of zinc and lead in plants  

Energy Technology Data Exchange (ETDEWEB)

In the Carpathian Basin, significant percentage of watershed area and floodplains of rivers are utilised agriculturally. Several potential sources of poisonous metal pollution have been identified in these areas. Because of spills from some of them a few severe accidents have happened especially in the watershed area of Tisza River during the last decades. The motivation of our present work was to produce {sup 62,65}Zn and {sup 203}Pb radioisotopes because they can be used especially as tracers for studying the kinetics of uptake, transport and accumulation of zinc and lead by plants under different circumstances. (orig.)

2004-07-01

485

Production of "6"2Zn, "6"5Zn and "2"0"3Pb radioisotopes for studying the transport of zinc and lead in plants  

International Nuclear Information System (INIS)

In the Carpathian Basin, significant percentage of watershed area and floodplains of rivers are utilised agriculturally. Several potential sources of poisonous metal pollution have been identified in these areas. Because of spills from some of them a few severe accidents have happened especially in the watershed area of Tisza River during the last decades. The motivation of our present work was to produce "6"2","6"5Zn and "2"0"3Pb radioisotopes because they can be used especially as tracers for studying the kinetics of uptake, transport and accumulation of zinc and lead by plants under different circumstances. (orig.)

486

Non-relativistic Fermions, Coadjoint Orbits of \\winf\\ and String Field Theory at $c=1$  

CERN Document Server

We apply the method of coadjoint orbits of \\winf-algebra to the problem of non-relativistic fermions in one dimension. This leads to a geometric formulation of the quantum theory in terms of the quantum phase space distribution of the fermi fluid. The action has an infinite series expansion in the string coupling, which to leading order reduces to the previously discussed geometric action for the classical fermi fluid based on the group $w_\\infty$ of area-preserving diffeomorphisms. We briefly discuss the strong coupling limit of the string theory which, unlike the weak coupling regime, does not seem to admit of a two dimensional space-time picture. Our methods are equally applicable to interacting fermions in one dimension.

1992-01-01

487

Lattice chiral effective field theory with three-body interactions at next-to-next-to-leading order  

Energy Technology Data Exchange (ETDEWEB)

We consider low-energy nucleons at next-to-next-to-leading order in lattice chiral effective field theory. Three-body interactions first appear at this order, and we discuss several methods for determining three-body interaction coefficients on the lattice. We compute the energy of the triton and low-energy neutron-deuteron scattering phase shifts in the spin-doublet and spin-quartet channels using Luescher's finite-volume method. In the four-nucleon system we calculate the energy of the {alpha}-particle using auxiliary fields and projection Monte Carlo. (orig.)

2009-07-15

488

Kinetics and mechanism of the reaction between portland cement and clinoptilolite  

International Nuclear Information System (INIS)

When clinoptilolite is immobilized in cement-based composites, a series of reactions occur, leading to release of Cs. These reactions occur in three overlapping stages: a rapid ion exchange, followed by a somewhat slower reaction between clinoptilolite and principally the Ca(OH)_2 component of cement, and, in the longer term, slower reactions with C-S-H leading either to formation of low-lime C-S-H at temperatures below 100"0C or 11 A (1.1 nm) tobermorite at higher temperatures. Kinetic data are presented to evaluate the rate of physical consumption of the zeolites at 70 and 150"0C. Reactions occurring above 100"0C appear to result in the development of extensive microcracking of cement-zeolite composites containing 50% zeolite.

489

Interactions at the cofired interface of Ag/Pd electrode and lead-based ferroelectrics  

Energy Technology Data Exchange (ETDEWEB)

In the present study, element interdiffusions at the cofired interface of 9/1 Ag/Pd electrode and lead magnesium niobate (PMN)-based ferroelectrics were investigated using Auger Electron Spectroscopy (AES). Intense interdiffusions at the interface were observed while Ag and Pd could penetrate into the ceramics for about 1 {mu}m. Ag-doping experiments were carried out to further study the effects of Ag diffusion on electrical properties of the ceramics. The results showed that Ag could be incorporated into solid solution of the ceramics as Ag{sup +}. As a whole, the Curie temperature (Tc) and dielectric constant of the ceramics decreased with Ag addition. However, Ag addition had no obvious effect on the insulation resistivity. The results inferred that Ag{sup +} could substitute for Pb{sup 2+} at A site of ABO{sub 3} lattice, thereby oxygen vacancies were generated.

2003-05-25

490

Integrated evolutionary neural network approach with distributed computing for congestion management  

British Library Electronic Table of Contents (United Kingdom)

Electric supply industry is facing deregulation all over the world. Under deregulated power supply scenario, power transmission congestion has become more intensified and recurrent, as compared to conventional regulated power system. Congestion may lead to violation of voltage or transmission capacity limits, thus threatens the power system security and reliability. Also the growing congestion may lead to unanticipated divergent electricity pricing. Owing to these facts congestion management has become a crucial issue in the deregulated power system scenario. Fast and precise prediction of nodal congestion prices in real time deregulated/spot power market may enable market participants and system operators to keep pace with the congestion by taking preventive measures like transaction resc...

2010-01-01

491

Influence of ion-beam carbon-fiber surface treatment on the angle of wetting by epoxy oligomers  

International Nuclear Information System (INIS)

The influence of the regimes of modification of carbon fibers by an argon ion beam on the change in the angle of their wetting by an epoxy oligomer has been investigated. It has been shown that ion-beam treatment of carbon fibers leads to a considerable decrease in the wetting angles (the difference between the wetting angles for non modified and modified fibers is up to 32.2-38.7). Accordingly, there is also an increase in the value of the equilibrium work of adhesion by 36.2-41.6% in the contact zone. It has been established that ion-beam treatment of carbon fibers by argon ions leads to an increase in the shear strength when microplastics based on them are formed. (authors)

492

Indirect Dark Matter Signals  

CERN Document Server

Dark Matter annihilation (DMA) may yield an excess of gamma rays and antimatter particles, like antiprotons and positrons, above the background from cosmic ray interactions. Several signatures, ranging from the positron excess, as observed by HEAT, AMS-01 and PAMELA, the gamma ray excess, as observed by the EGRET spectrometer, the WMAP-haze, and constraints from antiprotons, as observed by CAPRICE, BESS and PAMELA, have been discussed in the literature. Unfortunately, the different signatures all lead to different WIMP masses, indicating that at least some of these interpretations are likely to be incorrect. Here we review them and discuss their relative merits and uncertainties. New x-ray data from ROSAT suggests non-negligible convection in our Galaxy, which leads to an order of magnitude uncertainty in the yield of charged particles from DMA, since even a rather small convection will let drift the charged particles in the halo to outer ...

2008-01-01

493

Focused ion beam (FIB) milling of electrically insulating specimens using simultaneous primary electron and ion beam irradiation  

International Nuclear Information System (INIS)

There is currently great interest in combining focused ion beam (FIB) and scanning electron microscopy technologies for advanced studies of polymeric materials and biological microstructures, as well as for sophisticated nanoscale fabrication and prototyping. Irradiation of electrically insulating materials with a positive ion beam in high vacuum can lead to the accumulation of charge, causing deflection of the ion beam. The resultant image drift has significant consequences upon the accuracy and quality of FIB milling, imaging and chemical vapour deposition. A method is described for suppressing ion beam drift using a defocused, low-energy primary electron beam, leading to the derivation of a mathematical expression to correlate the ion and electron beam energies and currents with other parameters required for electrically stabilizing these challenging materials.

2007-02-07

494

Electrodeposition and magnetic properties of three-dimensional bulk and shell nickel mesostructures  

British Library Electronic Table of Contents (United Kingdom)

In this paper we demonstrate the electrodeposition of nickel, a common ferromagnetic material, in various magnetically desirable shapes including nanowires, nanoparticles and highly faceted shells. In order to obtain three dimensional mesostructures, the electrochemical deposition of nickel was performed on highly oriented pyrolytic graphite (HOPG) under different electrolyte composition and deposition potential conditions. Under potentiostatic deposition at one distinct potential negative with respect to the reversible potential of nickel, three stages of nucleation and growth take place leading to a complex morphology of deposits. However, dual-pulse potential deposition and electrodeposition in low pH solutions causing hydrogen evolution, lead to nickel deposits in the form of nanowires...

2011-01-01

495

Efficiency of a lead-containing tie for radiation protection of the thyroid gland  

Energy Technology Data Exchange (ETDEWEB)

During fluoroscopy the examiner is usually protected by a radiation-reducing body shield, leaving the thyroid unprotected. The fact that the thyroid is located in a region of the neck usually covered by the shirt collar led to the idea of designing a tie with lead core, providing easy and ''decorative'' reduction of the radiation dose. Sonographic examinations were carried out in 20 volunteers (10 men, 10 women) to determine the size of the gland and its coverage by such a tie. The reduction of the surface and organ dose was assessed using film dosimetry with scattered radiation, the body of the examiner being simulated by an Alderson phantom. On average 88% of the thyroid gland surface area was covered. Surface dose was reduced to 1%, and organ dose to 10% of the value without the protection tie. (Author).

1992-11-01

496

Efficiency of a lead-containing tie for radiation protection of the thyroid gland  

International Nuclear Information System (INIS)

During fluoroscopy the examiner is usually protected by a radiation-reducing body shield, leaving the thyroid unprotected. The fact that the thyroid is located in a region of the neck usually covered by the shirt collar led to the idea of designing a tie with lead core, providing easy and ''decorative'' reduction of the radiation dose. Sonographic examinations were carried out in 20 volunteers (10 men, 10 women) to determine the size of the gland and its coverage by such a tie. The reduction of the surface and organ dose was assessed using film dosimetry with scattered radiation, the body of the examiner being simulated by an Alderson phantom. On average 88% of the thyroid gland surface area was covered. Surface dose was reduced to 1%, and organ dose to 10% of the value without the protection tie. (Author).

497

Effect of chemical composition on the structure and mechanical properties of Mn-Al-C alloys in the magnetic region  

Energy Technology Data Exchange (ETDEWEB)

The thermal stability and deformability of Mn-Al-C alloys containing 0.6 pct C are investigated experimentally as a function of excess phase content. It is shown that an increase in Mn content from 68.9 to 73.5 pct leads to increased stability of the high-temperature epsilon phase. The enrichment of the system Mn-Al-Cu in Mn and Al above the optimum composition leads to the formation of nonmagnetic excess phases, eta and beta, which reduce the magnetization of the alloy. In addition, a decrease in thermal stability is observed in the alloy with 73.5 pct Mn due to the decomposition of the ferromagnetic phase. 7 references.

1988-01-01

498

Cyclotron produced lead-203  

International Nuclear Information System (INIS)

The radioactive isotopes of lead are reviewed with respect to their choice for in vitro tracer studies. The #gamma#-photon energy and absence of particle emission in the decay of "2"0"3Pb makes it particularly suitable for these applications. Reaction yields of "2"0"3Pb using "2"0"3Tl targets and proton, deuteron, "3He and "4He beams are listed. Using the preferred reaction "2"0"3Tl (d, 2n)"2"0"3Pb with a 15 MeV deuteron beam, yields of about 75 #mu#Ci #mu#Ahr"-"1, after chemical separation, are reported. Details of target design and chemical separation are given. (U.K.).

499

Chemical sensors based on surface-confined dendrimers  

Energy Technology Data Exchange (ETDEWEB)

The use of dendrimers for preparing chemically sensitive interfaces for detecting volatile organic compounds (VOCs) using surface acoustic wave (SAW) device transducers is described. Specifically, the synthesis of the dendrimers and the means by which they are affixed to SAW devices is discussed, followed by a detailed spectroscopic analysis of the surface-confined dendrimers and a discussion of their interaction with different VOCs. Most of these preliminary experiments focus on dendrimer surface modification using benzoylchloride, which leads to phenyl terminal groups linked to the dendrimer via amide groups. The results of this study lead us to conclude that dendrimers: (1) provide general specificity towards classes of functional groups and are therefore suitable for array-based sensing schemes; (2) are intermediate in structure between monolayers and polymers and exhibit the desirable properties of both; (3) can be straightforwardly ...

1997-10-01