WorldWideScience
1

Synthesis, solid and solution studies of paraquat dichloride calixarene complexes. Molecular modelling  

International Nuclear Information System (INIS)

The interaction of the herbicide paraquat dichloride (P Q, substrate) with p-tert-butylcalix arenas (L, receptor) was investigated in both the solution and solid states. The isolated paraquat calixarene complexes were characterised by UV-visible, 1H NMR, ESI-Ms, Luminescence and IR spectroscopies and elemental analysis. The stoichiometry of complexes 1 and 2 was 1:1 (1 herbicide: 1 calixarene) and both revealed a biexponential luminescence decay with lifetimes depending on the size and the conformational particularity of the calixarenes. Molecular modelling suggested that both calixarenes interact with the herbicide through cation-? interaction. P Q in included in the p-tert butylcalix a rene cavity, a situation favoured by its pinched conformation in polar solvent while it is partially included in the p-tert butylcalix a rene cavity because of its in-out cone conformation. The theoretical results, in ...

3

Interaction of insulin with a triblock copolymer of PEG-(fumaric-sebacic acids)-PEG: Thermodynamic and spectroscopic studies  

British Library Electronic Table of Contents (United Kingdom)

A comparative study on the interaction of (PEG-co-P(FA/SC)-co-PEG) triblock copolymer with bovine and human insulins was carried out using isothermal titration calorimetry (ITC), circular dichroism (CD), and fluorescence spectroscopy. ITC data show that the copolymer has a low affinity for both proteins, with an association constant of about 7?9?103?M ?1. Results also show that binding is enthalpically driven, and disfavored by conformational entropy. CD spectroscopy studies reveal a small increase in the helical content and a decrease in ?-structure as well as random coil in both proteins. Acrylamide quenching experiments display reduced accessibility of tyrosines, while intrinsic fluorescence spectra show lower tyrosine emission. Furthermore, thermal unfolding experiments, studied by far...

2007-01-01

4

Dendrosomes as novel gene porters-III  

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND: It was previously reported that dendrosomes, i.e. neutral, biodegradable, covalent or self-assembled, hyperbranched, spheroidal nano-particles with a size ranging from 15 to 100 nm, provide a convenient and efficient means of gene delivery into various kinds of cells such as human hepatoma and kidney cells as well as animal models.RESULTS: New studies via circular dichroism show that hydrophilic and amphipathic dendrosomes either do not affect the DNA structure or moderately transform it from B- to A-conformation. Gene delivery into human liver, kidney, and endothelial cells as well as other animal cells like Bowes, U-937, Raw, CCRF-CEM, MOLT-4, K562, Huh-7 and VERO reveal that the genes are efficiently expressed and in comparison with other gene porters like Lipofectin or bact...

2008-01-01

5

A novel structural mechanism for redox regulation of uridine phosphorylase 2 activity  

British Library Electronic Table of Contents (United Kingdom)

Uridine phosphorylase (UPP) catalyzes the reversible conversion of uridine to uracil and ribose-1-phosphate and plays an important pharmacological role in activating fluoropyrimidine nucleoside chemotherapeutic agents such as 5-fluorouracil and capecitabine. Most vertebrate animals, including humans, possess two homologs of this enzyme (UPP1 & UPP2), of which UPP1 has been more thoroughly studied and is better characterized. Here, we report two crystallographic structures of human UPP2 (hUPP2) in distinctly active and inactive conformations. These structures reveal that a conditional intramolecular disulfide bridge can form within the protein that dislocates a critical phosphate-coordinating arginine residue (R100) away from the active site, disabling the enzyme. In vitro activity measurem...

2011-01-01

6

The influence of tertiary structural restraints on conformational transitions in superhelical DNA.  

UK PubMed Central (United Kingdom)

This paper examines theoretically the effects that restraints on the tertiary structure of a superhelical DNA domain exert on the energetics of linking and the onset of conformational transitions. The...Full Text Available

1987-12-10

7

SQUID Eddy Current Technique Applying Conformable Eddy ...  

Science.gov (United States)

... Accession Number : ADD344580. Title : SQUID Eddy Current Technique Applying Conformable Eddy Current Probes,. Corporate Author : ...

8

Conformity, political participation, and economic rewards: The case of Chinese private entrepreneurs  

British Library Electronic Table of Contents (United Kingdom)

Using institutional and resource dependence theories as the conceptual framework, this study identifies three forms of conformity?political, economic, and social?that can affect the level of private entrepreneurs? formal political participation in a transition economy. Data from a 2004 national-wide survey of 3,012 private firms in China show that political conformity (indicated by membership in the ruling party), economic conformity (amount of taxes paid), and social conformity (amount of charity donated) are each antecedents to private entrepreneurs? formal political participation. Moreover, political conformity negatively moderates the relationship between social conformity and private entrepreneurs? formal political participation?for party members, a lesser amount of charity is associa...

2011-01-01

9

Conformational analysis of ethyl azidoformate  

International Nuclear Information System (INIS)

A conformational analysis of ethyl azidoformate (EAF) has been carried out by the MINDO/3 quantum-chemical method. It has been shown that EAF exists in the form of two conformers differing with respect to rotation around the C-N bond. Complete optimization of the geometry has been carried out for both conformers. It has been found that the transoid conformation is planar and that the cisoid conformation is nonplanar. The height of the rotation barrier is 15.4 kcal/mole. The optimal geometry of the transition state has been calculated. It has been noted that a significant role in the mechanism of the conformational transition is played by the inversion of a nitrogen, which facilitates the transition. The results of the calculation have been confirmed by IR-spectroscopic data.

10

Unified description of bradyons and tachyons based on the dynamical SO(4,2) symmetry  

International Nuclear Information System (INIS)

Firstly the so called 'conformal relativity' in the 6-dimensional conformal space is formulated. In particular the concept of dilatational degree of freedom - scale - is introduced. The special conformal transformations are interpreted as the transformations connecting dilatationally moving frames (and objects). The ideas, similar to those by Kaluza and Klein, can be applied to the conformal space to obtain a unification of gravitation and electromagnetism. Lastly the conformal symmetry is extended to imaginary scales and to negative scales. Particles having imaginary scales are shown to be tachyons, whilst particles with negative scales correspond to antiparticles. (Auth.).

11

Higher spin symmetries and w_#infinity# algebra in the conformal affine Toda model  

International Nuclear Information System (INIS)

As recently shown the conformal affine Toda models can be obtained via hamiltonian reduction from a two-loop Kac-Moody algebra. In this paper we propose a systematic procedure to analyze the higher spin symmetries of the conformal affine Toda models. The method is based on an explicit construction of infinite towers of extended conformal symmetry generators. Two fundamental building blocks of this construction are special spin-one and -two primary fields characterizing the conformal structure of these models. The connection to the algebra of area preserving diffeomorphisms on a two-manifold (w_#infinity# algebra) is established. (orig.).

1992-05-01

12

Recognition and Detoxification of the Insecticide DDT by Drosophila melanogaster Glutathione S-Transferase D1  

Energy Technology Data Exchange (ETDEWEB)

GSTD1 is one of several insect glutathione S-transferases capable of metabolizing the insecticide DDT. Here we use crystallography and NMR to elucidate the binding of DDT and glutathione to GSTD1. The crystal structure of Drosophila melanogaster GSTD1 has been determined to 1.1 {angstrom} resolution, which reveals that the enzyme adopts the canonical GST fold but with a partially occluded active site caused by the packing of a C-terminal helix against one wall of the binding site for substrates. This helix would need to unwind or be displaced to enable catalysis. When the C-terminal helix is removed from the model of the crystal structure, DDT can be computationally docked into the active site in an orientation favoring catalysis. Two-dimensional {sup 1}H,{sup 15}N heteronuclear single-quantum coherence NMR experiments of GSTD1 indicate that conformational changes occur upon glutathione and DDT binding and the residues that broaden upon DDT ...

2010-06-14

13

Identification of three related human GRO genes encoding cytokine functions  

International Nuclear Information System (INIS)

The product of the human GRO gene is a cytokine with inflammatory and growth-regulatory properties; GRO is also called MGSA for melanoma growth-stimulatory activity. The authors have identified two additional genes, GRO#beta# and GRO#gamma#, that share 90% and 86% identity at the deduced amino acid level with the original GRO#alpha# isolate. One amino acid substitution of proline in GRO#alpha# by leucine in GRO#beta# and GRO#gamma# leads to a large predicted change in protein conformation. Significant differences also exist in the 3' untranslated region, including different numbers of ATTTA repeats associated with mRNA instability. A 122-base-pair region in the 3' region is conserved among the three GRO genes, and a part of it is also conserved in the Chinese hamster genome, suggesting a role in regulation. DNA hybridization with oligonucleotide probes and partial sequence analysis of the genomic clones confirm that the three forms are derived from related but ...

14

A single amino acid substitution results in a retinoblastoma protein defective in phosphorylation and oncoprotein binding  

International Nuclear Information System (INIS)

The authors have previously identified a small-cell lung cancer cell line (NCI-H209) that expresses an aberrant, underphosphorylated form of the retinoblastoma protein RB1. Molecular analysis of RB1 mRNA from this cell line revealed a single point mutation within exon 21 that resulted in a nonconservative amino acid substitution (cysteine to phenylalanine) at codon 706. Stable expression of this mutant RB1 cDNA in a human cell line lacking endogenous RB1 demonstrated that this amino acid change was sufficient to inhibit phosphorylation. In addition, this cysteine-to-phenylalanine substitution also resulted in loss of RB1 binding to the simian virus 40 large tumor and adenovirus E1A transforming proteins. These results confirm the importance of exon 21 coding sequences and suggest that the cysteine residue at codon 706 may play a role in achieving a specific protein conformation essential for protein-protein interactions.

15

Molecular conformation, receptor binding, and hormone action of natural and synthetic estrogens and antiestrogens.  

UK PubMed Central (United Kingdom)

The X-ray crystallographic structural determinations of synthetic estrogens and antiestrogens provide reliable information on the global minimum energy conformation of these molecules or a local minimum...Full Text Available

1985-09-01

16

Conformational stability of alternating d (CG) oligomers in high salt solution.  

UK PubMed Central (United Kingdom)

The conformation of d (CG)n oligomers with n = 2,3 has been studied in aqueous solution in the presence of high salt concentration. A minimum n value of three is necessary to obtain a left-handed Z-helix....Full Text Available

1981-05-11

17

A model for the single stranded random coil form of polydeoxyadenylic acid from minimum energy conformations of the dimeric subunit.  

UK PubMed Central (United Kingdom)

The minimum energy conformations of dApdA have been examined for their suitability as buildings blocks of the single stranded coil form of polynucleotides. Calculations of the characteristic ratio C...Full Text Available

1978-09-01

18

The influence of intramolecular H-bond on chromatographic behavior of phenylalkylamines  

British Library Electronic Table of Contents (United Kingdom)

The thermodynamic characteristics of adsorption on the surface of graphitized thermal carbon black at 300 K were determined by the molecular statistical method for three phenylalklylamines. The influence of the intramolecular H-bond on the conformation of the molecules compared with structurally related n-alkyl-benzenes was considered. It was shown that the conformations of the molecules could influence chromatographic retention. Conformational isomers stabilized by intramolecular H-bonds were found to retain their structure in adsorption on graphitized thermal carbon black.

2009-01-01

19

The influence of intramolecular H-bond on chromatographic behavior of phenylalkylamines  

Science.gov (United States)

The thermodynamic characteristics of adsorption on the surface of graphitized thermal carbon black at 300 K were determined by the molecular statistical method for three phenylalklylamines. The influence of the intramolecular H-bond on the conformation of the molecules compared with structurally related n-alkyl-benzenes was considered. It was shown that the conformations of the molecules could influence chromatographic retention. Conformational isomers stabilized by intramolecular H-bonds were found to retain their structure in adsorption on graphitized thermal carbon black.

2009-04-01

20

Non-uniqueness in conformal formulations of the Einstein constraints  

CERN Document Server

Standard methods in non-linear analysis are used to show that there exists a parabolic branching of solutions of the Lichnerowicz-York equation with an unscaled source. We also apply these methods to the extended conformal thin sandwich formulation and show that if the linearised system develops a kernel solution for sufficiently large initial data then we obtain parabolic solution curves for the conformal factor, lapse and shift identical to those found numerically by Pfeiffer and York. The implications of these results for constrained evolutions are discussed.

2006-01-01

21

Search for extended conformal algebra  

International Nuclear Information System (INIS)

The authors search for the extended conformal algebra with two spin-s (s:integer) and one spin-1 generators. This search is inspired by the existence of chiral algebra in the Gaussian model for rational radius. For odd s, the conformal properties of the three-point functions imply that a general fusion rule can be reduced to those of the Gaussian model. For arbitrary even s, these conditions are weaker. In particular, for s = 2 the authors show that the chiral algebra of the Gaussian model is the unique extended conformal algebra with the value of the central charge fixed to be c = 1. It is also shown that the conformal generator is necessarily a bilinear of the spin-1 generator just as the Gaussian model. The authors conjecture that this remains true for arbitrary value of s.

1990-08-01

22

Visual search behaviour in skeletal radiographs: a cross-speciality study  

Energy Technology Data Exchange (ETDEWEB)

Aim: To determine whether experience improves the consistency of visual search behaviour in fracture identification in plain radiographs, and the effect of specialization. Material and methods: Twenty-five observers consisting of consultant radiologists, consultant orthopaedic surgeons, orthopaedic specialist registrars, orthopaedic senior house officers, and accident and emergency senior house officers examined 33 skeletal radiographs (shoulder, hand, and knee). Eye movement data were collected using a Tobii 1750 eye tracker with levels of diagnostic confidence collected simultaneously. Kullback-Leibler (KL) divergence and Gaussian mixture model fitting of fixation distance-to-fracture were used to calculate the consistency and the relationship between discovery and reflective visual search phases among different observer groups. Results: Total time spent studying the radiograph was not significantly different between the groups. However, the expert groups had a higher number of true ...

2007-11-15

23

Mapping of the human cone transducin {alpha} subunit (GNAT2) gene to 1p13 and mutation analysis in patients with Stargardt`s disease  

Energy Technology Data Exchange (ETDEWEB)

Transducin {alpha} subunits are members of a large family of G-proteins and play an important role in phototransduction in rod and cone photoreceptors. We report the localization of the human cone {alpha} transducin (GNAT2) gene using fluorescence in situ hybridization (FISH) on chromosome 1 in band p13. The recent assignment of a gene for Stargardt`s disease to the same chromosomal region by linkage analysis prompted us to investigate the possible role of GNAT2 in the pathogenesis of this disease. Stargardt`s disease is characterized by degeneration in late childhood or early adulthood of the macula of the retina, a region rich in cones. We screened patients with Stargardt`s disease, with or without peripheral cone involvement as monitored by the full-field ERG, for mutations in this gene. We investigated 66 unrelated patients including 22 with peripheral cone dysfunction for mutations in the coding region of the GNAT2 gene using polymerase chain reaction-single strand ...

1994-09-01

24

Crystal and solution structures of an odorant-binding protein from the southern house mosquito complexed with an oviposition pheromone  

Energy Technology Data Exchange (ETDEWEB)

Culex mosquitoes introduce the pathogens responsible for filariasis, West Nile virus, St. Louis encephalitis, and other diseases into humans. Currently, traps baited with oviposition semiochemicals play an important role in detection efforts and could provide an environmentally friendly approach to controlling their populations. The odorant binding proteins (OBPs) in the female's antenna play a crucial, if yet imperfectly understood, role in sensing oviposition cues. Here, we report the X-ray crystallography and NMR 3D structures of OBP1 for Culex quinquefasciatus (CquiOBP1) bound to an oviposition pheromone (5R,6S)-6-acetoxy-5-hexadecanolide (MOP). In both studies, CquiOBP1 had the same overall six-helix structure seen in other insect OBPs, but a detailed analysis revealed an important previously undescribed feature. There are two models for OBP-mediated signal transduction: (i) direct release of the pheromone from an internal binding pocket in a ...

2010-11-15

25

Scaling dimensions in hidden Kerr/CFT  

CERN Document Server

It has been proposed that a hidden conformal field theory (CFT) governs the dynamics of low frequency scattering in a general Kerr black hole background. We further investigate this correspondence by mapping higher order corrections to the massless wave equations in a Kerr background to an expansion within the CFT in terms of higher dimension operators. This implies the presence of infinite towers of CFT primary operators with positive conformal dimensions compatible with unitarity. The exact Kerr background softly breaks the conformal symmetry and the scaling dimensions of these operators run with frequency. The scale-invariant fixed point is dual to a degenerate case of flat spacetime.

2011-01-01

26

Infinite-parametric extension of the conformal algebra in D>2 space-time dimensions  

International Nuclear Information System (INIS)

On the basis of the analytic continuations of semisimple Lie algebras discovered recently by us we construct manifestly quasiconformal infinite-dimensional algebras AC(so(4, 1)) and PAC(so(3, 2)) extending the conformal algebras in three-dimensional euclidean and Minkowski space-time like the Virasoro algebra extends so(2, 1). Their higher spin generalizations are also constructed. A counterpart of the central extension for D > 2 and possible appplications in exactly solvable conformal quantum field models in D > 2 are discussed. (orig.).

1991-01-01

27

Conformal radiation therapy: technical requirements and clinical applications  

International Nuclear Information System (INIS)

Conformal radiation therapy represents a considerable and attractive challenge in oncology. Its aim is mainly to improve local control by increasing the dose with an acceptable rate of complications. This work overviews the world literature on this subject. The technical and theoretical requirements are highlighted. These requirements include a precise definition of the target volume by digital imaging (essentially CT scan), but also clear view of the target volume and the organs at risk, a specific collimation of the beam, 3-D dose calculations, optimization procedures, and a rigid immobilization of the patient with verification of his position. Moreover, the clinical applications of conformal radiation therapy are reviewed and discussed. (authors). 80 refs., 1 tab.

1995-01-01

28

A dose computation algorithm used in MLC conformal treatment  

International Nuclear Information System (INIS)

A dose calculation algorithm for MLC based conformal radiotherapy is described in this paper. The algorithm is formulated by the coordinate of MLC leaves. Verification on the algorithm is made by comparing the dose distributions generated by this algorithm with that generated by a Differential Convolution Superposition algorithm for various regular and irregular fields. The results demonstrate that the present algorithm has suitable accuracy and high computational efficiency, thus it could be useful for the treatment planning process in MLC based conformal radiotherapy, where the workload for interactively or automatically designing the shapes of MLC is heavy. (authors)

2007-12-01

29

Tensors, spinors, and functions on the unit sphere  

International Nuclear Information System (INIS)

A representation of tensors and spinors at a point of space-time as spin and conformally weighted functions on the unit sphere is derived. Methods for performing algebraic operations on tensors and spinors in this representation are discussed. (author).

30

SAXS studies on added-salt species dependence of conformation of fully-charged poly(L-glutamate) in aqueous solutions  

Energy Technology Data Exchange (ETDEWEB)

The effect of counter-ion species on the local conformation of fully-charged poly(L-glutamate) in added-salt aqueous solutions were studied by small-angle X-ray scattering(SAXS). In the case of presence of monovalent counter-ion, the scattering behaviour could be explained by taking into consideration the excluded volume effect and intermolecular-interface interaction on the scattering function of wormlike chain. On the other hand, since SAXS profile of the solution in the presence of divalent counter-ion well fitted to the scattering function of dendrimer, it suggested that the conformation of polymer chain in such solution would be more compact conformation than that of presence of monovalent ion.

2010-10-01

31

Metallic stent and stereotactic conformal radiotherapy for hilar cholangiocarcinoma  

International Nuclear Information System (INIS)

Objective: To evaluate the effect of metallic stent combined with stereotactic conformal radiotherapy (SCRT) for hilar cholangiocarcinoma. Methods: Fifty-four patients with hilar cholangiocarcinoma were analyzed, including 31 treated with stent plus stereotactic conformal radiotherapy (combined group) and 23 with metallic stent alone (control group). Results: The mean survival time of combined group was 11.1 #+-# 4.6 months, compared with 5.1 #+-# 2.8 months of the control group, giving a significant difference between the two groups (P<0.01). Conclusion: The combination of metallic stent and stereotactic conformal radiotherapy is more effective than metallic stent alone for unresectable hilar cholangiocarcinoma. (authors)

2005-01-01

32

Heat shock proteins as emerging therapeutic targets  

UK PubMed Central (United Kingdom)

Chaperones (stress proteins) are essential proteins to help the formation and maintenance of the proper conformation of other proteins and to promote cell survival after a large variety of environmental...Full Text Available

2005-11-01

33

Reversible conformational change in herpes simplex virus glycoprotein B with fusion-from-without activity is triggered by mildly acidic pH  

UK PubMed Central (United Kingdom)

BackgroundThe pre-fusion form of the herpes simplex virus (HSV) fusion protein gB undergoes pH-triggered conformational change in vitro and during viral entry (Dollery...Full Text Available

34

Infinite dimensional algebra for all the (super-)field theories in four dimensions  

International Nuclear Information System (INIS)

By reformulating the usual free massless field theories in terms of twistors we get systems which are invariant under an infinite dimensional algebra. This algebra contains the two-dimensional conformal algebra and the SU(2, 2) algebra as subalgebras. It turns out that these systems, which possess the four-dimensional complex manifold structure of the twistor space, can lead to a natural generalization of the notion of two-dimensional conformal field theories to four dimensions. (orig.).

1989-12-01

35

Conformational transitions of alternating purine-pyrimidine DNAs in perchlorate ethanol solutions.  

UK PubMed Central (United Kingdom)

Conformational transitions of poly(dA-dC).poly(dG-dT), poly(dA-dT).poly(dA-dT), and other alternating purine-pyrimidine DNAs were studied in aqueous ethanol solutions containing molar concentrations...Full Text Available

1995-11-01

36

Conformal field theories via Hamiltonian reduction  

International Nuclear Information System (INIS)

Constraining the SL(3) WZW-model we construct a reduced theory which is invariant with respect to the new chiral algebra W_3"2. This symmetry is generated by the stress-energy tensor, two bosonic currents with spins 3/2 and the U(1) current. We conjecture a Kac formula that describes the highly reducible representation for this algebra. We also discuss the quantum Hamiltonian reduction for the general type of constraints that leads to the new extended conformal algebras. (orig.).

1991-01-01

37

Comparing two strategies of dynamic intensity modulated radiation therapy (dIMRT) with 3-dimensional conformal radiation therapy (3DCRT) in the hypofractionated treatment of high-risk prostate cancer  

UK PubMed Central (United Kingdom)

BackgroundTo compare two strategies of dynamic intensity modulated radiation therapy (dIMRT) with 3-dimensional conformal radiation therapy (3DCRT) in the setting of hypofractionated...Full Text Available

38

Comparative study of convolution, superposition, and fast superposition algorithms in conventional radiotherapy, three-dimensional conformal radiotherapy, and intensity modulated radiotherapy techniques for various sites, done on CMS XIO planning system  

UK PubMed Central (United Kingdom)

The aim of this study is to compare the dosimetry results that are obtained by using Convolution, Superposition and Fast Superposition algorithms in Conventional Radiotherapy, Three-Dimensional Conformal...Full Text Available

2009-01-01

39

Bosonization of conformal ghosts in Witten's string theory  

International Nuclear Information System (INIS)

It is formulated Witten's proposal of a covariant open-string theory in terms of oscillator modes and shown that some basic axioms for the noncommutative geometry are obeyed as algebraic operations, which were defined previously from a geometrical point of view. Our strategy is based on the proper bosonization of the conformal ghost fields.

40

A new unified approach to bradyons and tachyons by conformal transformations  

International Nuclear Information System (INIS)

By using linearized conformal transformations in six dimensions, a new unified approach to bradyons (v"2< c"2) and tachyons (v"2>c"2) is suggested, the essential tool being (real and imaginary) dilatations. The usual ''Generalized Lorentz transformations'' are got, In six dimensions the quadrate form is always positive, both for bradyons and for tachyons.

41

Representation blocks of conformal fields for the N=4 SU(2)$_{k}$ superconformal algebras  

CERN Document Server

The representation theories of the SU(2).sub(k)-extended N=4 superconformal algebras (SCAs) with arbitrary level k are developed being based on their Feigin-Fuchs representations found recently by the present author. A basic unit of the representation blocks consisting of eight \\lq\\lq boson-like\\rq\\rq\\ and eight \\lq\\lq fermion-like\\rq\\rq\\ conformal fields is found to describe arbitrary representations of the $N$=4 SU(2)$_k$ SCAs, including {\\it unitary} and {\\it nonunitary} representations. The transformation properties of the fundamental sets of the conformal fields under the $N$=4 SU(2)$_k$ superconformal symmetries are given. Then, the whole sets of the charge-screening operators of the $N$=4 SU(2)$_k$ SCAs are identified out of the sixteen conformal fields in the basic unit of the representation blocks. The conditions for the {\\it eligible} charge-screening operators are analyzed in terms of the continuous ...

1994-01-01

42

Steady-state and transient photoconductivity in c-axis GaN nanowires grown by nitrogen-plasma-assisted molecular beam epitaxy  

International Nuclear Information System (INIS)

Analysis of steady-state and transient photoconductivity measurements at room temperature performed on c-axis oriented GaN nanowires yielded estimates of free carrier concentration, drift mobility, surface band bending, and surface capture coefficient for electrons. Samples grown (unintentionally n-type) by nitrogen-plasma-assisted molecular beam epitaxy primarily from two separate growth runs were examined. The results revealed carrier concentration in the range of (3-6)x10"1"6 cm"-"3 for one growth run, roughly 5x10"1"4-1x10"1"5 cm"-"3 for the second, and drift mobility in the range of 500-700 cm"2/(V s) for both. Nanowires were dispersed onto insulating substrates and contacted forming single-wire, two-terminal structures with typical electrode gaps of #approx =#3-5 #mu#m. When biased at 1 V bias and illuminated at 360 nm (3.6 mW/cm"2) the thinner (#approx =#100 nm diameter) nanowires with the higher background doping showed an abrupt increase in photocurrent ...

2010-02-01

43

Sequence analysis of the ATM gene in 20 patients with RTOG grade 3 or 4 acute and/or late tissue radiation side effects  

International Nuclear Information System (INIS)

Purpose: Patients with ataxia-telangiectasia (A-T) show greatly increased radiation sensitivity and cancer predisposition. Family studies imply that the otherwise clinically silent heterozygotes of this autosomal recessive disease run a 3.5 to 3.8 higher risk of developing cancer. In vitro studies suggest moderately increased cellular radiation sensitivity of A-T carriers. They may also show elevated clinical radiosensitivity. We retrospectively examined patients who presented with severe adverse reactions during or after standard radiation treatment for mutations in the gene responsible for A-T, ATM, considering a potential means of future identification of radiosensitive individuals prospectively to adjust dosage schedules. Material and Methods: We selected 20 cancer patients (breast, 11; rectum, 2; ENT, 2; bladder, 1; prostate, 1; anus, 1; astrocytoma, 1; Hodgkins lymphoma, 1) with Grade 3 to 4 (RTOG) acute and/or late tissue radiation side effects by reaction severity. DNA from the ...

1999-07-15

45

Real-time neutron scattering investigations of biological signal transduction dynamics  

Energy Technology Data Exchange (ETDEWEB)

During their catalytic cycle, proteins involved in biological signal transduction undergo unexpectedly large conformational changes, which are at the core of their biological functioning. Until now it has been extremely difficult to obtain experimental insight into the nature of these conformational changes. Mathematical modeling and time-resolved X-ray crystallography have resulted in probable routes along which these conformational changes may take place, but so far this fundamental biological phenomenon has hardly been tackled experimentally. Here, we report on an attempt to observe structural changes in Photoactive Yellow Protein with time-resolved small-angle neutron scattering using diffractometer D22 at the high-flux reactor of the Institut Laue-Langevin, Grenoble, France.

2005-07-01

46

Real-time neutron scattering investigations of biological signal transduction dynamics  

International Nuclear Information System (INIS)

During their catalytic cycle, proteins involved in biological signal transduction undergo unexpectedly large conformational changes, which are at the core of their biological functioning. Until now it has been extremely difficult to obtain experimental insight into the nature of these conformational changes. Mathematical modeling and time-resolved X-ray crystallography have resulted in probable routes along which these conformational changes may take place, but so far this fundamental biological phenomenon has hardly been tackled experimentally. Here, we report on an attempt to observe structural changes in Photoactive Yellow Protein with time-resolved small-angle neutron scattering using diffractometer D22 at the high-flux reactor of the Institut Laue-Langevin, Grenoble, France

2005-04-11

47

Newtonian photorealistic ray tracing of grating cloaks and correlation-function-based cloaking-quality assessment  

CERN Document Server

Grating cloaks are a variation of dielectric carpet (or ground- plane) cloaks. The latter were introduced by Li and Pendry. In contrast to the numerical work involved in the quasi-conformal carpet cloak, the refractive-index profile of a conformal grating cloak follows a closed and exact analytical form. We have previously mentioned that finite-size conformal grating cloaks may exhibit better cloaking than usual finite-size carpet cloaks. In this letter, we directly visualize their performance using photorealistic ray-tracing simulations. We employ a Newtonian approach that is advantageous compared to conventional ray tracing based on Snell's law. Furthermore, we quantify the achieved cloaking quality by computing the cross-correlations of rendered images. The cross-correlations for the grating cloak are much closer to 100% (i.e., ideal) than those for the Gaussian carpet cloak.

2010-01-01

48

Nearly Conformal QCD and AdS/CFT  

Energy Technology Data Exchange (ETDEWEB)

The AdS/CFT correspondence is a powerful tool to study the properties of conformal QCD at strong coupling in terms of a higher dimensional dual gravity theory. The power-law falloff of scattering amplitudes in the non-perturbative regime and calculable hadron spectra follow from holographic models dual to QCD with conformal behavior at short distances and confinement at large distances. String modes and fluctuations about the AdS background are identified with QCD degrees of freedom and orbital excitations at the AdS boundary limit. A description of form factors in space and time-like regions and the behavior of light-front wave functions can also be understood in terms of a dual gravity description in the interior of AdS.

2005-08-08

49

Constrained NBMPR analogue synthesis, pharmacophore mapping and 3D-QSAR modeling of equilibrative nucleoside transporter 1 (ENT1) inhibitory activity  

British Library Electronic Table of Contents (United Kingdom)

Conformationally constrained analogue synthesis was undertaken to aid in pharmacophore mapping and 3D-QSAR analysis of nitrobenzylmercaptopurine riboside (NBMPR) congeners as equilibriative nucleoside transporter 1 (ENT1) inhibitors. In our previous study [J. Med. Chem. 2003, 46, 831-837], novel regioisomeric nitro-1,2,3,4-tetrahydroisoquinoline conformationally constrained analogues of NBMPR were synthesized and evaluated as ENT1 ligands. 7-NO2-1,2,3,4-Tetrahydroisoquino-2-yl purine riboside was identified as the analogue with the nitro group in the best orientation at the NBMPR binding site of ENT1. In the present study, further conformational constraining was introduced by synthesizing 5prime-O,8-cyclo derivatives. The flow cytometrically determined binding affinities indicated that the...

2008-01-01

50

A new higher-spin algebra and the lone-star product  

International Nuclear Information System (INIS)

In two recent papers, we constructed a new N#->##infinity# limit of the W_N algebras, which we denote W_#infinity# having generators of conformal spins 2, 3, ..., with central terms for all spins. In this paper, we construct another new algebra, which we denote W_1_+_#infinity#, with generators of conformal spins, 1, 2, 3, ..., again with central terms for all spins. The requirement that the algebras be closed requires that one include the spin-1 generators in W_1_+_#infinity#, and prohibits their inclusion in W_#infinity#. Paralleling our analogous construction for W_#infinity#, we show that the new algebra can also be realised as the antisymmetric part of an associative 'lone-star' product, which also closes on the set of generators with conformal spins #>=#1. (orig.).

1990-06-01

51

q-Virasoro algebra, q-conformal dimensions and free q-superstring  

International Nuclear Information System (INIS)

The commutators of standard Virasoro generators and fields generate various representations of the centreless Virasoro algebra depending on a conformal dimension J of the field in question (J is related to the Bargmann index of SU(1,1) generated by L_m, m=0,#+-#1). We introduce the notion of q-conformal dimension for various oscillator realizations of q-deformed Virasoro (super)algebras proposed earlier. We use the field theoretical approach introduced recently in which the q-Virasoro currents L"#alpha# (z) are expressed as Schwinger-like point-split normally ordered quadratic expressions in elementary fields. We extend this approach and probe the elementary fields A(z) (the q-superstring coordinate, momentum and fermionic field) and their powers by the q-Virasoro generators L"#alpha#_m (i.e. we calculate the commutators [L"#alpha#_m,A(z)]) and show that to all of them can be assigned just the standard non-deformed ...

1996-12-01

52

Variation in the Definition of Clinical Target Volumes for Pelvic Nodal Conformal Radiation Therapy for Prostate Cancer  

UK PubMed Central (United Kingdom)

PurposeWe conducted a comparative study of Clinical Target Volume (CTV) definition of pelvic lymph nodes by multiple GU radiation oncologists looking at the levels...Full Text Available

2009-06-01

53

Two amyloid states of the prion protein display significantly different folding patterns  

UK PubMed Central (United Kingdom)

SummaryIt has been well established that a single amino acid sequence can give rise to several conformationally distinct amyloid states. The extent to which amyloid structures...Full Text Available

2010-07-23

54

Trypanosoma cruzi glycosomal glyceraldehyde-3-phosphate dehydrogenase does not conform to the 'hotspot' topogenic signal model.  

UK PubMed Central (United Kingdom)

The genes which encode glycosomal glyceraldehyde-phosphate dehydrogenase (gGAPDH) of Trypanosoma cruzi are arranged as a tandemly repeated pair on a single chromosome and are identical at the level...Full Text Available

1990-09-01

55

Role of Methoxypolyethylene Glycol on the Hydration, Activity, Conformation and Dynamic Properties of a Lipase in a Dry Film  

UK PubMed Central (United Kingdom)

A combined approach based on the use of ATR-FT/IR and steady-state fluorescence spectroscopy allowed to shed light on the effects of the additive methoxypolyethylene glycol (MePEG) on the hydration,...Full Text Available

2008-10-01

56

Quantum group structure in the unitary minimal model  

Energy Technology Data Exchange (ETDEWEB)

We obtain a symmetry algebra for any unitary minimal model by using the representation of conformal field theories. This symmetry algebra can be interpreted as a quantum group. The generalization to non-unitary minimal models is direct. (orig.).

1989-10-05

57

Quantum group structure in the unitary minimal model  

International Nuclear Information System (INIS)

We obtain a symmetry algebra for any unitary minimal model by using the representation of conformal field theories. This symmetry algebra can be interpreted as a quantum group. The generalization to non-unitary minimal models is direct. (orig.).

58

Prolonged signaling at the parathyroid hormone receptor by peptide ligands targeted to a specific receptor conformation  

UK PubMed Central (United Kingdom)

The parathyroid hormone receptor (PTHR) is a class B G protein-coupled receptor that plays critical roles in bone and mineral ion metabolism. Ligand binding to the PTHR involves interactions to both...Full Text Available

2008-10-28

59

Photophysics and optical switching in green fluorescent protein mutants  

UK PubMed Central (United Kingdom)

We demonstrate by using low-temperature high-resolution spectroscopy that red-shifted mutants of green fluorescent protein are photo-interconverted among three conformations and are, therefore, not...Full Text Available

2000-03-28

60

Non-contiguous regions of Z-DNA in a DNA dodecamer.  

UK PubMed Central (United Kingdom)

The conformation of the self-complimentary DNA dodecamer d(br5CGbr5CGAATTbr5CGbr5CG) has been investigated in a variety of salt and solvent conditions by one and two-dimensional 1H NMR. In low salt...Full Text Available

1989-10-11

61

Molecular dynamics of a ?B DNA element: base flipping via cross-strand intercalative stacking in a microsecond-scale simulation  

UK PubMed Central (United Kingdom)

The sequence-dependent structural variability and conformational dynamics of DNA play pivotal roles in many biological milieus, such as in the site-specific binding of transcription factors to target...Full Text Available

2008-09-01

62

Mitochondrial DNA Damage and Animal Longevity: Insights from Comparative Studies  

UK PubMed Central (United Kingdom)

Chemical reactions in living cells are under strict enzyme control and conform to a tightly regulated metabolic program. However, uncontrolled and potentially deleterious endogenous reactions occur,...Full Text Available

63

Laser-Assisted Single-Molecule Refolding (LASR)  

UK PubMed Central (United Kingdom)

To assemble into functional structures, biopolymers search for global minima through their folding potential energy surfaces to find the native conformation. However, this process can be hindered by...Full Text Available

2010-09-22

64

Exchange algebra and the Drinfeld-Sokolov theorem  

International Nuclear Information System (INIS)

We analyse the relation between the exchange algebra and the separation of the chiralities in classical Toda field theory. We show that there exists a conformally covariant Bloch wave basis such that the two chiralities commute. In terms of this basis we then reconstruct the periodic and local solution of Toda field theory. (orig.).

1991-01-01

65

Effects of PKA phosphorylation on the conformation of the Na,K-ATPase regulatory protein FXYD1  

UK PubMed Central (United Kingdom)

FXYD1 (phospholemman) is a member of an evolutionarily conserved family of membrane proteins that regulate the function of the Na,K-ATPase enzyme complex in specific tissues and specific physiological...Full Text Available

2009-11-01

66

A frequency-based approach to locate common structure for 2D-3D intensity-based registration of setup images in prostate radiotherapy  

UK PubMed Central (United Kingdom)

In many radiotherapy clinics, geometric uncertainties in the delivery of 3D conformal radiation therapy and intensity modulated radiation therapy of the prostate are reduced by aligning the...Full Text Available

2007-07-01

67

Vibrational Circular Dichroism: A developing spectroscopic technique for peptide and protein conformational studies  

International Nuclear Information System (INIS)

Electronic circular dichroism (ECD) of the n-#pi# and #pi# -#pi# transitions of the amide groups in the ultraviolet has become an indispensable tool for qualitative characterization of proteins in solution. Since the existence of such a spectrum (that is, of natural optical activity) comes from the three dimensional interaction of the chromophores in the molecule, CD is exquisitely sensitive to molecular conformation. However, in proteins, the amide transitions available in the near UV are limited in number and are broads and overlapping. Interactions among them yield information about the polymeric backbone, but since such amide electronic excitation are relatively delocalized, the resulting

1996-11-01

68

Operator algebra from fusion rules. Pt. 2  

International Nuclear Information System (INIS)

The classification of rational conformal field theories is essentially equivalent to the classification of all possible four-point functions for the primary fields of the theories. An interesting set of parameters appearing in the latter classification is given by the number and the positions of so-called apparent singularities of the differential equations which are obeyed by the four-point functions. The subject of this paper is a detailed analysis of the role played by these parameters. In particular the restrictions imposed on them by general principles of two-dimensional conformal field theory are worked out, and the implications on the classification programme are discussed. (orig.).

1992-11-01

69

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

70

Locked nucleic acid (LNA): High affinity targeting of RNA for diagnostics and therapeutics  

DEFF Research Database (Denmark)

Locked nucleic acid (LNA) is a nucleic acid analogue containing one or more LNA nucleotide monomers with a bicyclic furanose unit locked in an RNA mimicking sugar conformation. This conformational restriction results in unprecedented hybridization affinity towards complementary single stranded RNA and thus, makes LNA uniquely suited for mimicking RNA structures and sequence specific targeting of RNA in vitro or in vivo. The focus of this paper is on LNAantisense, LNA-modified siRNA (siLNA), and detection and analysis of microRNAs by LNA-modified oligonucleotide probes.

2005-01-01

71

Extended conformal algebras with N=1 supersymmetry  

Energy Technology Data Exchange (ETDEWEB)

Extended conformal algebras with supersymmetry (super-W/sub n/ algebra) is constructed and the algebras are shown to exist for special values of the central charge c. The super-W/sub n/ algebra containing currents of spin (5/2, 3) has a unitary representation (c=10/7) and a non-unitary one (c=-5/2), and the super-W/sub n/ algebra containing currents of spins (2, 5/2) has a non-unitary representation (c=-6/5).

1988-12-29

72

Distribution amplitudes of {sigma} and {lambda} and their electromagnetic form factors  

Energy Technology Data Exchange (ETDEWEB)

Based on QCD conformal partial wave expansion to leading order conformal spin accuracy, we present the light-cone distribution amplitudes (DAs) of {sigma} and {lambda} baryons up to twist 6. It is concluded that fourteen independent DAs are needed to describe the valence three-quark states of the baryons at small transverse separations. The nonperturbative parameters relevant to the DAs are determined within the framework of QCD sum rule method. With the obtained DAs, a simple investigation on the electromagnetic form factors of these baryons are given. The magnetic moments of the baryons are estimated by fitting the magnetic form factor with the dipole formula.

2009-04-15

73

Azidothymidine: crystal structure and possible functional role of the azido group  

Energy Technology Data Exchange (ETDEWEB)

The crystal and molecular structures of the anti-acquired immunodeficiency syndrome agent 3'-azido-3'-deoxythymidine (AZT) have been determined by x-ray diffraction. There are two crystallographically independent AZT molecules in the crystal asymmetric unit; they have similar conformation and differ primarily in the glycosyl torsion angle. Comparisons with a hydrated thymidylate structure indicate that the azido group does not significantly affect the gross conformational preference of the molecule. The comparisons also suggest possible functional roles for the azido group in enzyme binding.

1987-12-01

74

A multidisciplinary study investigating radiotherapy in Ewing's sarcoma: end results of POG no. 8346  

International Nuclear Information System (INIS)

Purpose: To determine if involved field radiation (IF) is equivalent to standard whole bone radiation (SF) in local tumor control; to establish patterns of failure following treatment; and to determine response, event-free survival (EFS), and overall survival rates from multidisciplinary therapy in Ewing's sarcoma. Methods and Materials: Between 1983 and 1988, 184 children with Ewing's sarcoma were enrolled onto Pediatric Oncology Group 8346 (POG 8346). A total of 178 (97%) met eligibility criteria; 6 had pathology other than Ewing's sarcoma. Induction chemotherapy of cyclophosphamide/doxorubicin (adriamycin )(C/A) x 12 weeks was followed by local treatment either surgery or radiation therapy and C/A, dactinomycin, and vincristine for 50 weeks. Resection was advised for patients with small primary tumors if accomplished without functional loss. Forty patients were randomized to receive SF, whole bone radiation to 39.6 Gy plus a 16.2 Gy boost (total 55.8 Gy) or IF to 55.8 Gy, and the ...

1998-08-01

75

Studies of the involvement of metal ions with several medicinal agents  

Energy Technology Data Exchange (ETDEWEB)

NMR and CD studies indicate that Mg/sup 2 +/ and Ca/sup 2 +/ are able to change the conformation of tetracycline in DMSO solution. This may affect the in vivo effect of tetracycline. Using /sup 23/Na NMR, the formation constant of NaLAS (LAS represents the anion of lasalocid A) was found to be 80 M/sup -1/ which is much smaller than that in less polar solvents. Spin-lattice relaxation measurements were made to study the binding sites of Gd/sup 3 +/ on Las in ChCl/sub 3/-DMF mixed solvent system. No intermediate conformation (between cyclic and open-chain) was found. LAS was found to be a good second-sphere ligand to inert transition-metal amines. NMR studies suggest that LAS is in cyclic conformation when bound to these metal amines. A new method for the synthesis of spin-labeled anticancer Pt(II) complexes was developed. It is very simple and gives high yield of pure spin-labeled Pt(II) complexes.

1985-01-01

76

W algebras in conformal quantum field theory  

International Nuclear Information System (INIS)

A new algorithm for constructing extensions of the Virasoro algebra by primary fields - so called W-algebras - is presented. With the help of REDUCE all W-algebras with one further primary field up to conformal dimension 9 were calculated. Furthermore I give an interpretation of the obtained results using fusion algebras. The algorithm could also be used for constructing extensions of the super Virasoro algebra which play an important role in superstring theory. I present two examples here. With using representation theory of Kac-Moody algebras I determine the minimal field content of the super W_3 algebra. Finally, the general coset models SU(2)_kxSU(2)_m/SU(2)_k_+_m and SU(3)_kxSU(3)_m/SU(3)_k_+m are investigated. I calculate which W-algebras are likely contained in these cosets. (orig.).

1991-01-01

77

Strings through the Microscope  

CERN Document Server

Over the last few years, string theory has changed profoundly. Most importantly, novel duality relations have emerged which involve gauge theories of brane excitations on one side and various closed string backgrounds on the other. In this lecture, we introduce the fundamental ingredients of modern string theory and explain how they are modeled through 2D (boundary) conformal field theory. This so-called `microscopic description' of strings and branes is an active research area with new results ranging from the classification and construction of boundary conditions to studies of 2D renormalization group flows. We shall provide an overview of such developments before concluding the lecture with an extensive outlook on some research that is motivated by current problems in string theory. This includes investigations of non-rational and non-unitary conformal field theories.

2004-01-01

78

Positive energy representations of the conformal quantum algebra  

International Nuclear Information System (INIS)

The positive-energy unitary irreducible representations of the q-deformed conformal algebra #delta#C_q = U_q(su(2,2)) are obtained by appropriate deformation of the classical ones. When the deformation parameter q is N -th root of unity, all these unitary representations become finite-dimensional. For his case we discuss in some detail the massless representations, which are also irreducible representations of the q-deformed Poincare subalgebra of #delta#C_q. Generically, their dimensions are smaller than the corresponding finite-dimensional non-unitary representation of su(2,2), except when N = 2 modul h + 1, where h is the helicity of the representations. The latter cases include the fundamental representations with h = #+-#1/2. (author). 10 refs.

1985-05-22

79

Gravity Dual for a Model of Perception  

CERN Document Server

One of the salient features of human perception is its invariance under dilatation in addition to the Euclidean group, but its non-invariance under special conformal transformation. We investigate a holographic approach to the information processing in image discrimination with this feature. We claim that a strongly coupled analogue of the statistical model proposed by Bialek and Zee can be holographically realized in scale invariant but non-conformal Euclidean geometries. We identify the Bayesian probability distribution of our generalized Bialek-Zee model with the GKPW partition function of the dual gravitational system. We provide a concrete example of the geometric configuration based on a vector condensation model coupled with the Euclidean Einstein-Hilbert action. From the proposed geometry, we study sample correlation functions to compute the Bayesian probability distribution.

2010-01-01

80

Fusion algebras of fermionic rational conformal field theories via a generalized Verlinde formula  

International Nuclear Information System (INIS)

We prove a generalization of the Verlinde formula to fermionic rational conformal field theories. The fusion coefficients of the fermionic theory are equal to sums of fusion coefficients of its bosonic projection. In particular, fusion coefficients of the fermionic theory connecting two conjugate Ramond fields with the identity are either one or two. Therefore, one is forced to weaken the axioms of fusion algebras for fermionic theories. We show that in the special case of fermionic W(2, #delta#)-algebras these coefficients are given by the dimensions of the irreducible representations of the horizontal subalgebra on the highest weight. As concrete examples we discuss fusion algebras of rational models of fermionic W(2, #delta#)-algebras including minimal models of the N = 1 super Virasoro algebra as well as N = 1 super W-algebras SW(3/2, #delta#). (orig.).

1994-02-01

81

Electron beam, ion beam, X-ray optical techniques for fabricating surface-acoustic-wave and thin-film optical devices  

International Nuclear Information System (INIS)

Most surface-acoustic-wave and thin-film optical devices are made by the planar fabrication process. The exposure of the pattern in the polymer film is the first and most crucial step in ensuring desired device geometry, dimensional control, and freedom from pattern distortion. The methods of exposing the polymer film include: optical projection, conventional contact printing, conformable photomask contact printing, holographic recording, scanning electron beam lithography, projection electron lithography, and x-ray lithography. In this paper scanning electron beam lithography, conformable photomask contact printing, holographic recording, and x-ray lithography are discussed. In the last section, ion beam etching of relief structures is discussed.

82

Biosorption of uranium (VI) by immobilized Aspergillus fumigatus beads  

Energy Technology Data Exchange (ETDEWEB)

Biosorption of uranium (VI) ions by immobilized Aspergillus fumigatus beads was investigated in a batch system. The influences of solution pH, biosorbent dose, U (VI) concentration, and contact time on U (VI) biosorption were studied. The results indicated that the adsorption capacity was strongly affected by the solution pH, the biosorbent dose and initial U (VI) concentration. Optimum biosorption was observed at pH 5.0, biosrobent dose (w/v) 2.5%, initial U (VI) concentration 60 mg L{sup -1}. Biosorption equilibrium was established in 120 min. The adsorption process conformed to the Freunlich and Temkin isothermal adsorption models. The dynamic adsorption model conformed to pseudo-second order model.

2010-06-15

83

Biopolymer system for permeability modification in porous media  

Energy Technology Data Exchange (ETDEWEB)

New technologies are needed to reduce the current high rate of well abandonment. Improved sweep efficiency, reservoir conformance, and permeability modification can have a significant impact on oil recovery processes. Microorganisms can be used to selectively plug high-permeability zones to improve sweep efficiency and impart conformance control. Studies of a promising microbial system for polymer production were conducted to evaluate reservoir conditions in which this system would be effective. Factors which can affect microbial growth and polymer production include salinity, pH, temperature, divalent ions, presence of residual oil, and rock matrix. Flask tests and coreflooding experiments were conducted to optimize and evaluate the effectiveness of this system. Nuclear magnetic resonance imaging (NMRI) was used to visualize microbial polymer production in porous media. Changes in fluid distribution within the pore system of the core were ...

1995-12-31

85

Vertex operator representation of OS/sub rho/(M/N)/sup (1)/  

Energy Technology Data Exchange (ETDEWEB)

Using the boson-fermion equivalence in 2-d conformal field theory and the boson-boson equivalence of the superconformal bosonic ghost fields of the string theory, the authors construct a level {Kappa} = +1 representation of the affine superalgebra OSp(M*N)/sup 1/ in terms of vertex operators.

1988-01-01

86

The poly dA helix: a new structural motif for high performance DNA-based molecular switches  

UK PubMed Central (United Kingdom)

We report a pH-dependent conformational transition in short, defined homopolymeric deoxyadenosines (dA15) from a single helical structure with stacked nucleobases at neutral pH to a double-helical,...Full Text Available

2009-05-01

87

Representations of the conformal Lie algebra in the space of tensor densities on the sphere  

CERN Document Server

Let ${\\mathcal F}_\\lambda(\\mathbb{S}^n)$ be the space of tensor densities on $\\mathbb{S}^n$ of degree $\\lambda$. We consider this space as an induced module of the nonunitary spherical series of the group $\\mathrm{SO}_0(n+1,1)$ and classify $(\\mathrm{so}(n+1,1),\\mathrm{SO}(n+1))$-sim$unitary submodules of ${\\mathcal F}_\\lambda(\\mathbb{S}^n)$ as a function of $\\lambda$.

2003-01-01

88

Prediction of conformational changes by single mutation in the hepatitis B virus surface antigen (HBsAg) identified in HBsAg-negative blood donors  

UK PubMed Central (United Kingdom)

BackgroundSelection of hepatitis B virus (HBV) by host immunity has been suggested to give rise to variants with amino acid substitutions at or around the 'a' determinant...Full Text Available

89

Initiation of conformal radiotherapy with a multileaf-collimator - An approach to clinical routine  

International Nuclear Information System (INIS)

The implementation of a three-dimensional conformal radiotherapy facility in the radiotherapy department of the Heinrich Heine University is described. Complex radiotherapy techniques with commercially available networked systems are introduced to improve clinical work. Over 18 month we have gained clinical experience with a PHILIPS Multileaf Collimator (MLC) mounted on a SL 25 linear accelerator. For a limited period the MLC was used as a conventional blocking device. The standard MLC-shapes are controlled with a stand-alone computer system. In addition, a three-dimensional treatment planning system (3-D-TPS / TMS-Radix, Helax AB) based on convolution/superposition algorithms was recently installed. Treatment optimization is achieved using static field arrangements with complete volumetric computerized tomographic patient data for 3-D-TPS. Conformal adaptation of the 95%-isodose to the Planning Target Volume (PTV, ICRU 50) results in ...

1995-10-01

90

Inflation in a renormalizable cosmological model and the cosmic no-hair conjecture  

Energy Technology Data Exchange (ETDEWEB)

The possibility of having inflation in a renormalizable cosmological model is investigated. The cosmic no-hair conjecture is proved to hold for all Bianchi types except Bianchi type IX. By the use of a conformal transformation on the metric we show that these models are equivalent to the ones described by the Einstein-Hilbert action for gravity minimally coupled to a set of scalar fields with inflationary potentials. Henceforth, we prove that inflationary solutions behave as attractors in solution space, making it a natural event in the evolution of such models.

1989-05-15

91

Inflation in a renormalizable cosmological model and the cosmic no-hair conjecture  

International Nuclear Information System (INIS)

The possibility of having inflation in a renormalizable cosmological model is investigated. The cosmic no-hair conjecture is proved to hold for all Bianchi types except Bianchi type IX. By the use of a conformal transformation on the metric we show that these models are equivalent to the ones described by the Einstein-Hilbert action for gravity minimally coupled to a set of scalar fields with inflationary potentials. Henceforth, we prove that inflationary solutions behave as attractors in solution space, making it a natural event in the evolution of such models.

92

Emittance of investment casting molds  

Energy Technology Data Exchange (ETDEWEB)

This document describes measurements of the directional spectral emittance of four ceramic mold materials. The work was performed with the samples at {approximately} 900{degree}C in a vacuum vessel pumped to {approximately}3 {times} 10{sup {minus}6}Torr. Results conform to expectations derived from prior work done with similar samples.

1994-07-15

93

Depth of origin of the gas content in thermal waters  

Energy Technology Data Exchange (ETDEWEB)

The gas composition of recent thermal waters is in perfect conformity with their geologic-tectonic positions. The composition of gas-liquid inclusions in the basic-hyperbasic xenoliths of basaltoid lavas depends on the depth from which xenoliths are supplied. (The depth is determined by using the methods of geological thermobarometers). By comparing available data the conclusion was drawn that the gas compositions of thermal waters reflect the depth of generation of deep fluid which heats them and depends on the penetration depth of the fluid-conducting fissure zones.

1980-01-01

94

Cyclopeptide alkaloids. Synthesis of the ring system and its ion affinity  

International Nuclear Information System (INIS)

Several examples of the 14-membered, para-bridged ring system of the cyclopeptide alkaloids have been synthesized via an active ester cyclization. The yield of monomeric cyclopeptide varied from 1 to 33% and was affected by the amino acid substitution pattern and amide conformation of the linear peptide precursors. Both the synthetic models and a naturally occurring cyclopeptide alkaloid, ceanothine B, bind monovalent (Li"+) and divalent (Ca"2"+, Mg"2"+) cations. 4 figures, 1 table.

95

Conformational Changes in BAK, a Pore-forming Proapoptotic Bcl-2 Family Member, upon Membrane Insertion and Direct Evidence for the Existence of BH3-BH3 Contact Interface in BAK Homo-oligomers*  

UK PubMed Central (United Kingdom)

During apoptosis, the pro-apoptotic Bcl-2 family proteins BAK and BAX form large oligomeric pores in the mitochondrial outer membrane. Apoptotic factors, including cytochrome c, are...Full Text Available

2010-09-10

96

Bosonic realization of a universal W-algebra and Z_#infinity# parafermions  

International Nuclear Information System (INIS)

We construct a field theoretic representation of the universal W-algebra proposed by Pope, Romans and Shen, using a free complex boson in two dimensions. The resulting symmetry algebra is generated by conformal fields with spin 2, 3, 4, ... and has central charge c=2. Highest-weight representations are also given in terms of vertex operators. Furthermore, we discuss the relation of this representation to the theory of Z_#infinity# parafermions. (orig.).

1990-10-01

97

Adenine and guanine recognition of stop codon is mediated by different N domain conformations of translation termination factor eRF1  

UK PubMed Central (United Kingdom)

Positioning of release factor eRF1 toward adenines and the ribose-phosphate backbone of the UAAA stop signal in the ribosomal decoding site was studied using messenger RNA (mRNA) analogs containing...Full Text Available

2011-09-01

98

ATP Hydrolysis in Eg5 Kinesin Involves a Catalytic Two-water Mechanism*?  

UK PubMed Central (United Kingdom)

Motor proteins couple steps in ATP binding and hydrolysis to conformational switching both in and remote from the active site. In our kinesin·AMPPPNP crystal structure, closure of the active...Full Text Available

2010-02-19

99

A simple model of dimensional collapse  

CERN Document Server

We consider a simple model of d families of scalar field interacting with geometry in two dimensions. The geometry is locally flat and has only global degrees of freedom. When d0 it collapses to a one dimensional manifold. The model has some, but not all, of the characteristics believed to be features of the full theory of conformal matter interacting with quantum gravity which has local geometric degrees of freedom.

1996-01-01

101
102

Genetic Applications in Avian Conservation  

Science.gov (United States)

... structure along an elevational gradient in Hawaiian honeycreepers reveals contrasting evolutionary responses to avian malaria. BMC Evolutionary Biology 8: ... ...

104

DEVELOPMENT OF KSC PROGRAM FOR INVESTIGATING AND - NASA Technical ...  

Science.gov (United States)

Aluminum electrolytic capacitors, with 1043 failures, are a good example. Also, categorization by size and voltage reveals such frequencies of occurrence as ...

105

Complex fluid analysis with the advanced distillation curve approach.  

Science.gov (United States)

An improved method for measuring distillation curves reveals the physicochemical properties of complex fluids such as fuels. PMID:20041713

2010-02-01

107

Tertiary structure prediction of C-peptide of ribonuclease A by multicanonical algorithm  

CERN Document Server

We have performed multicanonical Monte Carlo simulations of C-peptide of ribonuclease A. It is known by CD and NMR experiments that this peptide has high alpha-helix content in aqueous solution and that the side-chain charges of residues Glu-2$^-$ and His-12$^+$ play an important role in the stability of the alpha-helix. In order to confirm these experimental implications, we have used two analogues of the peptide with charged and neutral side chains of Glu-2 and His-12. Two dielectric functions, distance-dependent and constant, are considered to study the effects of solvent contributions. All the simulations were started from random initial conformations. Various thermodynamic quantities such as average helicity as a function of residue number and average distance between two side chains as a function of temperature are calculated. The results are found to be in accord with the implications of CD and NMR experiments. The lowest-energy ...

1998-01-01

108

Synthesis of alkylated deoxyno irimycin and 1,5-dideoxy-1,5-iminoxylitol analogues: : Polar side-chain modification, sulfonium and selenonium heteroatom variants, conformational analysis, and evaluation as glycosidase inhibitors  

DEFF Research Database (Denmark)

The syntheses of N-alkylated deoxynojirimycin and 1,5-dideoxy-1,5-iminoxylitol derivatives having either a D- or an L-erythritol-3-sulfate functionalized N-substituent are reported. The alkylating agent used was a cyclic sulfate derivative, whereby selective attack of the nitrogen atom at the least hindered primary center afforded the desired ammonium salt. In aqueous solution, these salts were configurationally labile at the ammonium center. Sulfonium and/or selenonium analogues of the ammonium salts were prepared by analogous reactions. The chalcogen salts were obtained as mixtures of diastereomers, separable in some cases, differing only in the stereochemistry at the configurationally stable sulfur or selenium atoms. Proof of configuration and conformation of each compound was obtained by detailed NMR experiments. The compounds are six-membered ring analogues of salacinol, a known sulfonium-salt glucosidase inhibitor. Evaluation of the target compounds for ...

2004-01-01

109

New Insights into the Design of Inhibitors of Human S-Adenosylmethionine Decarboxylase: Studies of Adenine C[superscript 8] Substitution in Structural Analogues of S-Adenosylmethionine  

Energy Technology Data Exchange (ETDEWEB)

S-Adenosylmethionine decarboxylase (AdoMetDC) is a critical enzyme in the polyamine biosynthetic pathway and depends on a pyruvoyl group for the decarboxylation process. The crystal structures of the enzyme with various inhibitors at the active site have shown that the adenine base of the ligands adopts an unusual syn conformation when bound to the enzyme. To determine whether compounds that favor the syn conformation in solution would be more potent AdoMetDC inhibitors, several series of AdoMet substrate analogues with a variety of substituents at the 8-position of adenine were synthesized and analyzed for their ability to inhibit hAdoMetDC. The biochemical analysis indicated that an 8-methyl substituent resulted in more potent inhibitors, yet most other 8-substitutions provided no benefit over the parent compound. To understand these results, we used computational modeling and X-ray crystallography to study C{sup 8}-substituted adenine ...

2009-04-02

110

Four small puzzles that Rosetta doesn't solve  

CERN Document Server

A complete macromolecule modeling package must be able to solve the simplest structure prediction problems. Despite recent successes in high resolution structure modeling and design, the Rosetta software suite fares poorly on deceptively small protein and RNA puzzles, some as small as four residues. To illustrate these problems, this manuscript presents extensive Rosetta results for four well-defined test cases: the 20-residue mini-protein Trp cage, an even smaller disulfide-stabilized conotoxin, the reactive loop of a serine protease inhibitor, and a UUCG RNA tetraloop. In contrast to previous Rosetta studies, several lines of evidence indicate that conformational sampling is not the major bottleneck in modeling these small systems. Instead, approximations and omissions in the Rosetta all-atom energy function currently preclude discriminating experimentally observed conformations from de novo models at atomic resolution. These molecular ...

2011-01-01

111

Enzymatic synthesis and carbon-13 nuclear magnetic resonance conformational studies of disaccharides containing #beta#-D-galactopyranosyl and #beta#-D-[1-"1"3C]Galactopyranosyl residues  

International Nuclear Information System (INIS)

Partially purified UDPgalactosyltransferase (EC 2.4.1.22) from bovine milk has been used to synthesize millimolar amounts of compounds such as Gal#beta#(1#->#4)Glc, Gal#beta#(1#->#4)GlcNAc-#beta#-hexanolamine, and Gal#beta#(1#->#4)-GlcNAc#beta#(1#->#4)GlcNAc. The same method has been used to prepare similar compounds containing "1"3C-enriched galactopyranosyl moieties. Gal#beta#(1#->#4)GlcNAc-#beta#-hexanolamine was also synthesized in a solid-phase system in which the GlcNAc-#beta#-hexanolamine glycoside was covalently linked to agarose beads. At pH 7.0 and at 1 to 5 mM Mn"2"+"+ the yields of the galactosyl saccharides are greater than 90% by using 10% excess of UDPGal donor. The use of a 90% enriched [1-"1"3C]galactosyl residue allowed the determination of the most abundant conformer about the galactopyranosyl-glycoside linkage by analysis of the carbon-carbon coupling constants from Cl to Gal to the C3', C4', and C5' of GlcNAc or Glc. 3 figures, 1 ...

112

Effect of water content on the activity of lipase-hydrolysis of olive oil in reverse micelles. Gyakuso micelle nai ni okeru lipase no olive oil kasui bunkai hanno no gansuiritsu izonsei  

Energy Technology Data Exchange (ETDEWEB)

Hydrolysis of olive oil by Chromobacterium viscosum lipase was studied in a reverse micellar system of a anionic surfactant Aerosol OT (AOT) and isooctane. Different methods of solubilization of the micellar system afford specific dependence of enzymatic activity of the lipase on the water content in the micelles. In an injection method, water content is controlled by the amount of injected water, which determines the micelle size and hydrophobicity of the micelle without salt addition and changes reversibly the conformation of lipase corresponding to the change of lipase activity. The activity reaches the maximum at a water content (water/AOT)of 7. In a phase transfer method, water content is determined by salt concentration in the aqueous phase in contact with micelles and the water content corresponding to the maximum activity is 12 to 13, below which the activity decrese drastically. Addition of taurodeoxycholic acid to the AOT micelles suppresses the ...

1992-01-10

113

Detection of constitutive heterodimerization of the integrin Mac-1 subunits by fluorescence resonance energy transfer in living cells  

International Nuclear Information System (INIS)

Macrophage differentiation antigen associated with complement three receptor function (Mac-1) belongs to #beta#_2 subfamily of integrins that mediate important cell-cell and cell-extracellular matrix interactions. Biochemical studies have indicated that Mac-1 is a constitutive heterodimer in vitro. Here, we detected the heterodimerization of Mac-1 subunits in living cells by means of two fluorescence resonance energy transfer (FRET) techniques (fluorescence microscopy and fluorescence spectroscopy) and our results demonstrated that there is constitutive heterodimerization of the Mac-1 subunits and this constitutive heterodimerization of the Mac-1 subunits is cell-type independent. Through FRET imaging, we found that heterodimers of Mac-1 mainly localized in plasma membrane, perinuclear, and Golgi area in living cells. Furthermore, through analysis of the estimated physical distances between cyan fluorescent protein (CFP) and yellow fluorescent protein (YFP) fused to Mac-1 subunits, we ...

2006-08-04

114

Density functional calculations of 15N chemical shifts in solvated dipeptides  

International Nuclear Information System (INIS)

We performed density functional calculations to examine the effects of solvation, hydrogen bonding, backbone conformation, and the side chain on 15N chemical shielding in proteins. We used N-methylacetamide (NMA) and N-formyl-alanyl-X (with X being one of the 19 naturally occurring amino acids excluding proline) as model systems. In addition, calculations were performed for selected fragments from protein GB3. The conducting polarizable continuum model was employed to include the effect of solvent in the density functional calculations. Our calculations for NMA show that the augmentation of the polarizable continuum model with the explicit water molecules in the first solvation shell has a significant influence on isotropic 15N chemical shift but not as much on the chemical shift anisotropy. The difference in the isotropic chemical shift between the standard ?-sheet and ?-helical conformations ranges from 0.8 to 6.2 ppm depending on the residue ...

2008-06-01

115

Coal structure construction system with construction knowledge and partial energy evaluation; Kochiku chishiki to bubunteki energy hyoka ni yoru sekitan bunshi kozo kochiku system  

Energy Technology Data Exchange (ETDEWEB)

The computer aided coal structure construction system is proposed, and a computational construction example is presented. The coal structure construction engine of this system fabricates molecular structure by connecting fragments sequentially inputted through a user interface. The best structure candidate is determined using construction knowledge and partial energy evaluation every addition of one fragment, and this process is subsequently repeated. The structure evaluation engine analyzes the 3-D conformation candidate by molecular dynamics, and evaluates the conformation by determining the energy value of an optimum structure. As an example, this system was applied to construction of coal molecular structure based on the actual data of partial structure composed of 26 structures from 2l kinds of aromatic cluster structures, 27 bonds from 2 kinds of bridged bonds, and 16 groups from 2 kinds of terminal substitutional groups. As a result, ...

1996-10-28

116

Waste Sampling and Characterization Facility (WSCF). Maintenance Implementation Plan  

Energy Technology Data Exchange (ETDEWEB)

This Maintenance Implementation Plan has been developed for maintenance functions associated with the Waste Sampling and Characterization Facility (WSCF). This plan is developed from the guidelines presented by Department of Energy (DOE) Order 4330.4A, Maintenance Management Program (DOE 1990), Chapter II. The objective of this plan is to provide baseline information for establishing and identifying WHC conformance programs and policies applicable to implementation of DOE order 4330.4A guidelines. In addition, this maintenance plan identifies the actions necessary to develop a cost-effective and efficient maintenance program at WSCF.

1993-07-01

117

W_3-algebra constructed from the SU(3) parafermion  

International Nuclear Information System (INIS)

A construction of a W_3-algebra for the SU(3) parafermion is proposed. The details of the calculation are given, in which the Z-algebra technique is used instead of the popular free field realization. We find that the W_3-algebra is closed at level k=3, and the central charge of the underlying algebra is different from known series of Fateev-Lykyanov W-algebras; as a by-product we get a field T"("4")(z), whose conformal dimension is 4, and is null at k=3. ((orig.)).

8730-01-01

118

Two-dimensional (half-) integer spin conformal theories with central charge c < 1  

Energy Technology Data Exchange (ETDEWEB)

A generalized integral representation involving two types of charges is explored to construct correlation functions on the plane for c = 1 - 6/(m(m + 1)) < 1 discrete unitary Virasoro series. The various local operator product algebras emerging contain integer, or half-integer, spin fields along with scalar fields. The examples also include a generalization for arbitrary m of the Z/sub 2/sup -// statistics of the Ising model order-disorder fields.

1988-01-01

119

Radiological performance assessment for the E-Area Vaults Disposal Facility  

Energy Technology Data Exchange (ETDEWEB)

This report is the first revision to ``Radiological Performance Assessment for the E-Area Vaults Disposal Facility, Revision 0'', which was issued in April 1994 and received conditional DOE approval in September 1994. The title of this report has been changed to conform to the current name of the facility. The revision incorporates improved groundwater modeling methodology, which includes a large data base of site specific geotechnical data, and special Analyses on disposal of cement-based wasteforms and naval wastes, issued after publication of Revision 0.

2000-04-11

120

Production of a potassium silicate fertilizer from fly ash and red mud  

Energy Technology Data Exchange (ETDEWEB)

A study is reported of the use of three types of fly ash as a raw material in the production of a potassium silicate fertilizer. The results of high-temperature X-ray diffraction, calcination tests and chemical analyses indicate that a potassium silicate fertilizer conforming with fertilizer specifications can be produced by appropriate regulation of calcining temperature and the amounts of Fe/sub 2/0/sub 3/, Al/sub 2/O/sub 3/, MgO and CaO added. The results of tests of fertilizers incorporating red mud are also reported.

1985-01-01

121

Performance of rubber heat-stable and radiation-stable seals in helium coolant lines  

International Nuclear Information System (INIS)

The integrity of helium circulation loop flanged joints has been attracting recent attention as a design problem, in the development of high-temperature facilities incorporating helium loops (e.g., the VRG-50 pilot nuclear facility). Elevated temperatures and pressures, and the radiation environment, impose additional requirements on sealant materials. This applies first and foremost to rubber seals, which have found widespread favor on account of its excellent elasticity, its ability to spontaneously conform to possible changes in the clearance in the seal assembly, and the low compressive stresses developed in the flange joint assembly.

122

Microeconomics of the ideal gas like market models  

CERN Document Server

We develop a framework based on microeconomic theory from which the ideal gas like market models can be addressed. A kinetic exchange model based on that framework is proposed and its distributional features have been studied by considering its moments. Next, we derive the moments of the CC model (Eur. Phys. J. B 17 (2000) 167) as well. Some precise solutions are obtained which conform with the solutions obtained earlier. Finally, an output market is introduced with global price determination in the model with some necessary modifications.

2009-01-01

123

Kasner asymptotics of mixmaster Horava-Witten and pre-big-bang cosmologies  

Energy Technology Data Exchange (ETDEWEB)

We discuss various superstring effective actions and, in particular, their common sector which leads to the so-called pre-big-bang cosmology (cosmology in a weak coupling limit of heterotic superstring theory). Using the conformal relationship between these two theories we present Kasner asymptotic solutions of Bianchi type IX geometries within these theories and make predictions about possible emergence of chaos. Finally, we present a possible method of generating Horava-Witten cosmological solutions out of the well-known general relativistic or pre-big-bang solutions.

2001-09-01

124

Kasner asymptotics of mixmaster Horava-Witten and pre-big-bang cosmologies  

International Nuclear Information System (INIS)

We discuss various superstring effective actions and, in particular, their common sector which leads to the so-called pre-big-bang cosmology (cosmology in a weak coupling limit of heterotic superstring theory. Using the conformal relationship between these two theories we present Kasner asymptotic solutions of Bianchi type IX geometries within these theories and make predictions about possible emergence of chaos. Finally, we present a possible method of generating Horava-Witten cosmological solutions out of the well-known general relativistic or pre-big-bang solutions.

2001-09-01

125

Integration of SPECT with CT to plan radiotherapy fields. n application to conformal irradiation for lung carcinoma  

International Nuclear Information System (INIS)

Single photon emission computed tomography (SPECT) of lung perfusions permits to map functioning lung parenchyma with higher sensitivity than CT. Delivering higher radiations doses it used to increase local control in lung carcinoma; this strategy is based on radiobiological and clinical studies. Lung parenchyma is a dose-limiting tissue in patients irradiated for lung cancer. Functional mapping based on SPECT and CT findings permits to design radiation beams such as to minimize irradiation of functioning lung.

1999-04-01

126

Gas-liquid phase equilibrium in the system carbon dioxide-hexametapol (hexamethylphosphoramide)  

Energy Technology Data Exchange (ETDEWEB)

The authors investigated phase equilibria in the system carbon dioxide-hexametapol. Vacuum-distilled solvent of ''pure'' grade was used. The solubility of CO/sub 2/ in hexametapol under pressures at various temperatures and the temperature dependence of the Henry's law coefficient is show. It is concluded that the solubility of carbon dioxide in hexametapol in the temperature and pressure ranges corresponding to the operating conditions of industrial equipment for removing CO/sub 2/ from gases conforms to the Krichevskii-II'inskaya equation. The experimental data can be used for equipment design.

1985-09-01

127

Documentation of a model action plan to deter illicit nuclear trafficking  

International Nuclear Information System (INIS)

Theft, illegal possession, smuggling, or attempted unauthorized sale of nuclear and radiological materials remains a worldwide problem. The Nuclear Smuggling International Technical Working Group (ITWG) has adopted a model action plan to guide investigation of these cases through a systematic approach to nuclear forensics. The model action plan was recently documented and provides recommendations concerning incident response, collection of evidence in conformance with required legal standards, laboratory sampling and distribution of samples, radioactive materials analysis, including categorization and characterization of samples, forensics analysis of conventional evidence, and case development including interpretation of forensic signatures. (author)

2008-05-01

128

Digital AVR application to power plants  

Energy Technology Data Exchange (ETDEWEB)

The digital AVR must have the level of redundancy and control functions that conform to the configuration of the excitation control system and to the importance of a particular generator for the user. The digital AVR is not simply a digital version of the analog AVR, but can realize sophisticated control functions that were difficult to achieve with analog circuits, thus making it possible to enhance the stability of power system by PSS (power system stabilizer). This paper describes the test results of the digital AVRs applied to power plants, their system configuration and functions, as well as the outline of an auto-tuning PSS or AT-PSS planned to be incorporated in the digital AVR in the future.

1993-12-01

129

Determination of fast neutron flux distribution in irradiation sites of the Malaysian Nuclear Agency research reactor  

British Library Electronic Table of Contents (United Kingdom)

Determination of thermal to fast neutron flux ratio (ffast) and fast neutron flux (phi-fast) is required for fast neutron reactions, fast neutron activation analysis, and for correcting interference reactions. The ffast and subsequently phi-fast were determined using the absolute method. The ffast ranged from 48 to 155, and the phi-fast was found in the range 1.03x1010-4.89x1010 n cm-2 s-1. These values indicate an acceptable conformity and applicable for installation of the fast neutron facility at the MNA research reactor.

2011-01-01

130

Computer-assisted rotation and multiple stationary irradiation technique  

International Nuclear Information System (INIS)

A computer-assisted rotation and stationary conformation radiotherapy system with overrunning multileaf collimators has been developed. This system can produce any shape of target volume, including a number of target areas outside the axis of the rotation, regardless of the location of the axis at 360"0 rotation irradiation. In addition, by changing the dose rate and deleting a partial region within a field, multiple stationary irradiation can produce more homogeneous target volumes - thus avoiding excessive irradiation to critical organs - than the rotation technique. (orig.).

131

Chiral crystallization and the origin of chiral life on earth  

British Library Electronic Table of Contents (United Kingdom)

Abstract The creation of chirality on Earth and the development of chiral life have been discussed in this highlight. Convincing evidence for the introduction of chirality on Earth is still fragmentary. We believe that by a combination of chiral crystallization and formation of helical polymers with preferred chiral conformational structure is the key to this question. This concept of macromolecular asymmetry has inspired ideas and resulted in possible rules for how chiral life as we know it, could have been introduced. These investigations needed the understanding of the requirements for chiral crystallization, for the stereochemistry of the initial formation of helical polymers, the measurements of optical activity of solids and their coordination with the fundamentals of chirality. Spac...

2011-01-01

132

Adsorption of benzyl alcohol and 1-phenylethanol on graphitized thermal carbon black  

British Library Electronic Table of Contents (United Kingdom)

The adsorption of benzyl alcohol and 1-phenylethanol on graphitized thermal carbon black at 300 K is investigated. Thermodynamic characteristics of the adsorption of conformers stable in the gas phase and in the adsorbed state are determined by a molecular statistics method. The geometry of the molecules is optimized using the MP2 and B3LYP methods with a 6-311++G(d,p) basis set. Using the PBE0/6-31G(d) method, it is established that, in the adsorption of benzyl alcohol, two types of interactions, CH?O and OH??GTCB, occur. It is shown that, in 1-phenylethanol, intramolecular interactions are maintained.

2010-01-01

133

Actions for the environment  

CERN Document Server

As an International Organization, one the most important issues that CERN has to respect and guarantee is the protection of the environment. Several of ST activities and operations have a direct impact on the environment: civil engineering works, electrical (transformers) and air-cooling operation, chemical products storage, various waste disposal etc.... Important measures, taken in the past, have to be kept and new ones should be applied in order to insure the conformity of the infrastructure with existing legislation, the correct operation of equipment and systems, the constant monitoring of the different situations and the traceability of the events. Moreover good management of the environment would bring large savings to CERN.

2003-01-01

134

Acceptance test of full scope simulator of Daya Bay NPP  

International Nuclear Information System (INIS)

The author describes the purpose, classification and main process of acceptance test of full scope simulator of Daya Bay Nuclear Power Plant, including the correction of non-conformance items which are discovered during the performance of acceptance tests. The results of the acceptance tests show that the model accepted by the full scope simulator of Daya Bay Nuclear Power Plant is fully able to cope with the simulation of normal transients and incidental transients and the performance of the simulator indeed compiled with the technical specifications which are defined n the relevant contracts.

135

VIGILANCE, PREDATION RISK, AND THE ALLEE EFFECT IN DESERT BIGHORN SHEEP  

Science.gov (United States)

... 2004)068[0519:VPRATA]2.0.CO;2 VIGILANCE, PREDATION RISK, AND THE ALLEE EFFECT IN DESERT ... revealed that predation risk (as es...

136

Uncorrelated Randomness of the Heart Rate Is Associated with Sepsis in Sick Premature Infants  

UK PubMed Central (United Kingdom)

BackgroundLate-onset sepsis in the premature infant is frequently revealed by severe, unusual and recurrent bradycardias. In view of the high morbidity and mortality...Full Text Available

2009-03-01

137

Teachers' perceptions of epilepsy.  

UK PubMed Central (United Kingdom)

A questionnaire survey undertaken among 142 schoolteachers in North Staffordshire revealed most of the respondents did not feel confident when teaching children who had epilepsy and a minority considered...Full Text Available

1992-12-01

138

Status of Tern Colonies in the Honduras Bay Islands  

Science.gov (United States)

... herbaceous and low succulents (mostly Sesuvium portulacastrum, also Ipomea sp., Euphorbia sp.). Local informants revealed that historic colonies ... vegetation (Sesuvium portulacastrum, Suriana maritima, ...

139

Particle-Gas Dynamics and Primary Accretion - Space Science and ...  

Science.gov (United States)

the revealed stage of T Tauri star evolution, is only a mere shadow of its former self. Once primary accretion starts, one has the (poorly quantified) ...

140

NRAO: Press Releases  

Science.gov (United States)

Evolution in Space Radio Telescopes Reveal Youngest Stellar Corpse Gas Clouds in Whirlpool Galaxy Yield Important Clues Supporting Theory on Spiral Arms Starbust-driven Winds...

2011-10-09

141

Graphs and Grammars for Histology: An Introduction  

UK PubMed Central (United Kingdom)

The invention of the microscope disclosed a whole new world, that of the hitherto invisibly small. Histologic evidence as revealed by the microscope has become a cornerstone of medical diagnosis, and...Full Text Available

1979-10-17

142

Epigenetic mechanisms underlying human epileptic disorders and the process of epileptogenesis  

UK PubMed Central (United Kingdom)

The rapidly emerging science of epigenetics and epigenomic medicine promises to reveal novel insights into the susceptibility to and the onset and progression of epileptic disorders. Epigenetic...Full Text Available

2010-07-01

143

Deformation and seismicity of Taiwan  

UK PubMed Central (United Kingdom)

14C-dated Holocene coastal uplift, conventional and satellite geodetic measurements, and coseismic and aseismic fault slip reveal the pattern of distributed deformation at Taiwan resulting...Full Text Available

2000-10-10

144

Is uniform target dose possible in IMRT plans in the head and neck?  

International Nuclear Information System (INIS)

Purpose: Various published reports involving intensity-modulated radiotherapy (IMRT) plans developed using automated optimization (inverse planning) have demonstrated highly conformal plans. These reported conformal IMRT plans involve significant target dose inhomogeneity, including both overdosage and underdosage within the target volume. In this study, we demonstrate the development of optimized beamlet IMRT plans that satisfy rigorous dose homogeneity requirements for all target volumes (e.g., #+-#5%), while also sparing the parotids and other normal structures. Methods and Materials: The treatment plans of 15 patients with oropharyngeal cancer who were previously treated with forward-planned multisegmental IMRT were planned again using an automated optimization system developed in-house. The optimization system allows for variable sized beamlets computed using a three-dimensional convolution/superposition dose calculation and flexible cost ...

2002-04-01

145

Epitope mapping and functional analysis of sigma A and sigma NS proteins of avian reovirus  

International Nuclear Information System (INIS)

We have previously shown that avian reovirus (ARV) #sigma#A and #sigma#NS proteins possess dsRNA and ssRNA binding activity and suggested that there are two epitopes on #sigma#A (I and II) and three epitopes (A, B, and C) on #sigma#NS. To further define the location of epitopes on #sigma#A and #sigma#NS proteins and to further elucidate the biological functions of these epitopes by using monoclonal antibodies (MAbs) 62, 1F9, H1E1, and 4A123 against the ARV S1133 strain, the full-length and deletion fragments of S2 and S4 genes of ARV generated by polymerase chain reaction (PCR) were cloned into pET32 expression vectors and the fusion proteins were overexpressed in Escherichia coli BL21 strain. Epitope mapping using MAbs and E. coli-expressed deletion fragments of #sigma#A and #sigma#NS of the ARV S1133 strain, synthetic peptides, and the cross reactivity of MAbs to heterologous ARV strains demonstrated that epitope II on #sigma#A was located at amino acid residues ...

2005-02-20

146

Effect of D-amino acids at Asp"2"3 and Ser"2"6 residues on the conformational preference of A#beta#_2_0_-_2_9 peptides  

International Nuclear Information System (INIS)

The effects of D-amino acids at Asp"2"3 and Ser"2"6 residues on the conformational preference of #beta#-amyloid (A#beta#) peptide fragment (A#beta#_2_0_-_2_9) have been studied using different spectroscopic techniques, namely vibrational circular dichroism (VCD), vibrational absorption, and electronic circular dichroism. To study the structure of the A#beta#_2_0_-_2_9, [D-Asp"2"3]A#beta#_2_0_-_2_9, and [D-Ser"2"6]A#beta#_2_0_-_2_9 peptides under different conditions, the spectra were measured in 10 mM acetate buffer (pH 3) and in 2,2,2-trifluoroethanol (TFE). The spectroscopic results indicated that at pH 3, A#beta#_2_0_-_2_9 peptide takes random coil with #beta#-turn structure, while [D-Ser"2"6]A#beta#_2_0_-_2_9 peptide adopts significant amount of polyproline II (PPII) type structure along with #beta#-turn contribution and D-Asp-substituted peptide ([D-Asp"2"3]A#beta#_2_0_-_2_9) adopts predominantly PPII type structure. The increased propensity for PPII ...

2005-09-30

147

The structure of the W_#infinity# algebra  

International Nuclear Information System (INIS)

We prove rigorously that the structure constants of the leading (highest spin) linear terms in the commutation relations of the conformal chiral operator algebra W_#infinity# are identical to those of the Diff_0"+ R"2 algebra generated by area preserving diffeomorphisms of the plane. Moreover, all quadratic terms of the W_N algebra are found to be absent in the limit N#->##infinity#. In particular we show that W_#infinity# is a central extension of Diff_0"+ R"2 with non-trivial cocycles appearing only in the commutation relations of its Virasoro subalgebra. We also propose a representation of W_#infinity# in terms of a single scalar field in 2+1 dimensions and discuss its significance in the context of quantum field theory. (orig.).

1990-01-01

148

The ribosome and the mechanism of protein synthesis  

Energy Technology Data Exchange (ETDEWEB)

In virtually all forms of life on earth, proteins in each cell are made according to a genetic blueprint, in the form of DNA. The translation of copies of this genetic blueprint (in the form of messenger RNA) into polypeptides is performed on the ribosome, a highly complex molecular machine composed of RNAs and proteins. To this end, special adaptor molecules called transfer RNAs are lined up by the ribosome in the sequence dictated by the genetic code, such that the amino acids carried by these molecules can be linked into a polypeptide. Several cofactors are involved in these processes, some of which require energy freed up by GTP hydrolysis. Although the ribosome was discovered more than 50 years ago, its structure has only been solved recently by X-ray crystallography. Another technique, cryo-electron microscopy, is starting to contribute toward our understanding of the ribosome's function, by portraying its conformational changes and binding ...

2006-05-01

149

The minimal series of N=1 and N=2 superconformal topological field theory  

International Nuclear Information System (INIS)

We obtain conformal invariant topological field theories with N = 2 supersymmetry by twisting Sevrin, Troost and Van Proeyen's SU(2) x SU(2) x U(1) extended N = 4 superconformal field theories. We expect that the number of physical states is finite although the original N = 4 theories have continuous spectra. It is shown that the number of physical states is actually finite when the central charge c < 6 in the corresponding N = 4 theories. The physical states inherit the structure of the chiral ring in N = 2 superconformal minimal series which is obtained by the reduction from N = 4 theories. We also show that the algebra contains the topological N = 4 superconformal algebra as subalgebra. Therefore a closed set of a finite number of physical states in the topological N = 1 superconformal algebra can also be obtained. (orig.).

1991-06-01

150

Stop-and-go kinetics in amyloid fibrillation  

CERN Document Server

Many human diseases are associated with protein aggregation and fibrillation. We present experiments on in vitro glucagon fibrillation using total internal reflection fluorescence microscopy, providing real-time measurements of single-fibril growth. We find that amyloid fibrils grow in an intermittent fashion, with periods of growth followed by long pauses. The observed exponential distributions of stop and growth times support a Markovian model, in which fibrils shift between the two states with specific rates. Remarkably, the probability of being in the growing (stopping) state is very close to 1/4 (3/4) in all experiments, even if the rates vary considerably. This finding suggests the presence of 4 independent conformations of the fibril tip; we discuss this possibility in terms of the existing structural knowledge.

2009-01-01

151

Scattering of discrete states in two-dimensional open string field theory  

Energy Technology Data Exchange (ETDEWEB)

This is the second in a series of papers devoted to open string field theory in two dimensions. In this paper we aim to clarify the origin and the role of discrete physical states in the theory. To this end, we study interactions of discrete states and generic tachyons. In particular, we discuss at length four point amplitudes. We show that the behavior of the correlation functions is governed by the number of generic tachyons involved and values of the kinematic invariants [ital s], [ital t], and [ital u]. The divergence of certain classes of correlators is shown to be the consequence of the fact that certain kinematic invariants are nonpositive integers in that case. Explicit examples are included. We check our results by the standard conformal technique.

1993-12-15

152

Regulations on health/functional foods in Korea  

International Nuclear Information System (INIS)

The term 'health/functional food' (HFF) refers to food supplements containing nutrients or other substances (in a concentrated form) that have a nutritional or physiological effect whose purpose is to supplement the normal diet. The Korean Health/Functional Food Act that came into effect in 2004 requires these products to be marketed in measured doses, such as in pills, tablets, capsules, and liquids. HFFs are of two types: generic and product-specific. There are 37 ingredients listed in the act for generic HFFs, and if an HFF contains a new active ingredient that is not included in the generic 37 products, it is considered a product-specific HFF. The standardization, safety, and efficacy of a new active ingredient are reviewed by the Korean Food and Drug Administration in order to receive approval as a product-specific HFF. Conforming with international standards and protecting public health requires constant upgrading of the Health/Functional Food Act.

2006-04-03

153

Radiation therapy in the treatment of hilar cholangiocarcinoma  

International Nuclear Information System (INIS)

The incidence of hilar cholangiocarcinoma is very rare worldwide. Radical resection is the only prognostic factor for long survival in patients with hilar cholangiocarcinoma. Postoperative radiation therapy can improve local control and survival rates for patients with palliative resection, but it remains controversial in patients with radical resection. Biliary drainage can effectively release bile duct obstruction for the majority of patients with locally advanced disease, and may even prolong survival when combined with radiation therapy. Radiation therapy includes extrernal beam therapy alone, external beam therapy with intraluminal brachytheapy and new radiation technique, such as three dimentional conformal therapy and intensity modulated radiation therapy. The propective randomized clinical study is needed for further investigation in the role of combined modality therapy especially for hilar cholangiocarcinoma. (authors)

2007-10-01

154

Radiation therapy and Ewing's sarcoma in childhood  

International Nuclear Information System (INIS)

Despite high local control rate in Ewing's sarcoma the exact indication of radiation therapy is still controversial as well as the choice of the target volume and the optimal dose of radiation. The importance of the quality of radiotherapy has been stressed in recently published data and has shown a significant impact on long term local control with adequate radiation therapy. The dramatic improvement of precision allowed by the conformal therapy and three dimensional dosimetry allow to expect a decrease of late effects expected for second malignancies. However, late sequelae and radio-induced osteosarcoma still remain the major side effects after radiotherapy. The authors discuss the results of the main trials on Ewing's sarcoma on the choice of dose and target volume. Surgery is still the preferred choice for small tumors if the foreseen outcome is identical. (authors). 28 refs.

155

Of McKay Correspondence, Non-linear Sigma-model and Conformal Field Theory  

CERN Document Server

The ubiquitous ADE classification has induced many proposals of often mysterious correspondences both in mathematics and physics. The mathematics side includes quiver theory and the McKay Correspondence which relates finite group representation theory to Lie algebras as well as crepant resolutions of Gorenstein singularities. On the physics side, we have the graph-theoretic classification of the modular invariants of WZW models, as well as the relation between the string theory nonlinear $\\sigma$-models and Landau-Ginzburg orbifolds. We here propose a unification scheme which naturally incorporates all these correspondences of the ADE type in two complex dimensions. An intricate web of inter-relations is constructed, providing a possible guideline to establish new directions of research or alternate pathways to the standing problems in higher dimensions.

2000-01-01

156

Numerical simulation of conformational variability in biopolymer translocation through wide nanopores  

CERN Document Server

Numerical results on the translocation of long biopolymers through mid-sized and wide pores are presented. The simulations are based on a novel methodology which couples molecular motion to a mesoscopic fluid solvent. Thousands of events of long polymers (up to 8000 monomers) are monitored as they pass through nanopores. Comparison between the different pore sizes shows that wide pores can host a larger number of multiple biopolymer segments, as compared to smaller pores. The simulations provide clear evidence of folding quantization in the translocation process as the biopolymers undertake multi-folded configurations, characterized by a well-defined integer number of folds. Accordingly, the translocation time is no longer represented by a single-exponent power law dependence on the length, as it is the case for single-file translocation through narrow pores. The folding quantization increases with the biopolymer length, while the rate of translocated beads at each time step is ...

2009-01-01

157

Non-destructive Imaging of Individual Bio-Molecules  

CERN Document Server

Radiation damage is considered to be the major problem that still prevents imaging an individual biological molecule for structural analysis. So far, all known mapping techniques using sufficient short wave-length radiation, be it X-rays or high energy electrons, circumvent this problem by averaging over many molecules. Averaging, however, leaves conformational details uncovered. Even the anticipated use of ultra-short but extremely bright X-ray bursts of a Free Electron Laser shall afford averaging over 10^6 molecules to arrive at atomic resolution. Here we present direct experimental evidence for non-destructive imaging of individual DNA molecules. In fact, we show that DNA withstands coherent low energy electron radiation with deBroglie wavelength in the Angstrom regime despite a vast dose of 10^8 electrons/nm^2 accumulated over more than one hour.

2009-01-01

158

Matrix models as CFT: Genus expansion  

International Nuclear Information System (INIS)

We show how the formulation of the matrix models as conformal field theories on a Riemann surfaces can be used to compute the genus expansion of the observables. Here we consider the simplest example of the Hermitian matrix model, where the classical solution is described by a hyperelliptic Riemann surface. To each branch point of the Riemann surface we associate an operator which represents a twist field dressed by the modes of the twisted boson. The partition function of the matrix model is computed as a correlation function of such dressed twist fields. The perturbative construction of the dressing operators yields a set of Feynman rules for the genus expansion, which involve vertices, propagators and tadpoles. The vertices are universal, the propagators and the tadpoles depend on the Riemann surface. As a demonstration we evaluate the genus-two free energy using the Feynman rules.

2010-10-01

159

Mapping of the human cone transducin {alpha}-subunit (GNAT2) gene to 1p13 and negative mutation analysis in patients with Stargardt disease  

Energy Technology Data Exchange (ETDEWEB)

We report localization of the human cone transducin (GNAT2) gene using fluorescence in situ hybridization on chromosome 1 in band p13. The recent assignment of a gene for Stargardt disease to the same chromosomal region by linkage analysis prompted us to investigate the possible role of GNAT2 in the pathogenesis of this disease. We investigated 66 unrelated patients for mutations in the coding region of the GNAT2 gene using polymerase chain reaction-single strand conformation polymorphism analysis (SSCP) and direct sequencing. No disease-specific mutations were found, indicating that GNAT2 is probably not involved in the pathogenesis of most cases of Stargardt disease. 19 refs., 1 fig., 1 tab.

1995-01-01

160

Kinetics of a reactive dye adsorption onto dolomitic sorbents.  

Science.gov (United States)

A novel wastewater treatment technique has been investigated, for reactive dye removal, in batch kinetic systems. These experimental studies have indicated that charred dolomite has the potential to act as an adsorbent for the removal of Brilliant Red reactive dye from aqueous solution. The effect of initial dye concentration, adsorbent mass:liquid volume ratio, and agitation speed on dye removal have been determined with the experimental data mathematically described using empirical external mass transfer and intra-particle diffusion models. The experimental data show conformity with an adsorption process, with the removal rate heavily dependent on both external mass transfer and intra-particle diffusion. PMID:12691893

2003-05-01

161

Kinetic manifestation of cooperative interaction between quinuclidinyl benzilate and rat brain muscarine cholinoreceptors  

Energy Technology Data Exchange (ETDEWEB)

A study was made of the kinetics of L-(/sup 3/H)quinuclidinyl benzilate binding with membrane-bound muscarine cholinoreceptors from the rat brain. Determination was made of the rate constants of this process, and constants as a function of ligand concentration was investigated, indicating that there is a complex mechanism of interaction of antagonists with muscarine receptor. With up to 3.5 nM concentrations of L-(/sup 3/H)quinuclidinyl benzilate, the binding reaction occurs in two stages: rapid equilibrated binding is followed by a slow process of conformational isomerization of the receptor-ligand complex. At higher ligand concentrations, there is additional drastic increase in constant of rate of ligand binding a new plateau is reached. Such dependence of rate constant on ligand concentration is indicative of the cooperative nature of interaction between antagonists and muscarine receptors. This is possible if there are in the receptor complex several binding ...

1985-01-01

162

K S Krishnan and the early experimental evidences for the Jahn-Teller Theorem  

CERN Document Server

Jahn-Teller theorem, proposed in 1937, predicts a distortional instability for a molecule that has symmetry based degenerate electronic states. In 1939 Krishnan emphasized the importance of this theorem for the arrangement of water molecules around the transition metal or rare earth ions in aqueous solutions and hydrated saltes, in a short and interesting paper published in Nature by pointing out atleast four existing experimental results in support of the theorem. This paper of Krishnan has remained essentially unknown to the practitioners of Jahn-Teller effect, eventhough it pointed to the best experimental results that were available, in the 30's and 40's, in support of Jahn-Teller theorem. Some of the modern day experiments are also in conformity with some specific suggestions of Krishnan.

1998-01-01

163

Influence of recycling and temperature on the swelling ability of paper  

British Library Electronic Table of Contents (United Kingdom)

Hornification is the loss of fiber wall swelling which is detrimental to subsequent recycling resulting from drying. It is known that dried fibers lose their conformability and swelling capacity. The effect of recycling treatment on the swelling ability of hardwood bleached kraft pulp fibers was determined. Modelling paper recycling, sheets were recycled using heat treatment (23?C, 60?C, 100?C). The results were compared with those for natural fibers from bleached kraft pulp. Swelling kinetics of sheets was measured by a modified method monitoring interactions of pulp with water. Swelling ability decreased during the recycling in comparison with never-recycled pulp at all temperatures. Recycling of sheets caused only small changes in the cupri-ethylene-diamine viscosity, however, the water...

2011-01-01

164

Grading of quality assurance requirements  

International Nuclear Information System (INIS)

The present Manual provides guidance and illustrative examples for applying a method by which graded quality assurance requirements may be determined and adapted to the items and services of a nuclear power plant in conformance with the requirements of the IAEA Nuclear Safety Standards (NUSS) Code and Safety Guides on quality assurance. The Manual replaces the previous publication IAEA-TECDOC-303 on the same subject. Various methods of grading quality assurance are available in a number of Member States. During the development of the present Manual it was not considered practical to attempt to resolve the differences between those methods and it was preferred to identify and benefit from the good practices available in all the methods. The method presented in this Manual deals with the aspects of management, documentation, control, verification and administration which affect quality. 1 fig., 4 tabs.

165

Geothermal resource maps and bottom hole temperature surveys  

Energy Technology Data Exchange (ETDEWEB)

Knowledge of subsurface temperatures obtained from heat flow and equilibrium temperature measurements were used as a basis for evaluation of the usefulness of the non-equilibrium temperatures of oil and gas wells for geothermal exploration. We find that the data in the Geothermal Gradient Map of North America do not conform to the thermal regime of Nebraska; and, that if the BHT data were the only data used, we would have underestimated our resource by about 80%. Differences in geological sections and heat flow between Nebraska and the U.S. Gulf coast where the correction data for the USGS map were obtained are the reasons for the discrepency. Some significant inaccuracies in the BHT data may not be correctable.

1982-10-01

166

Experimental parameterization of an energy function for the simulation of unfolded proteins  

DEFF Research Database (Denmark)

The determination of conformational preferences in unfolded and disordered proteins is an important challenge in structural biology. We here describe an algorithm to optimize energy functions for the simulation of unfolded proteins. The procedure is based on the maximum likelihood principle and employs a fast and efficient gradient descent method to find the set of parameters of the energy function that best explain the experimental data. We first validate the method by using synthetic reference data, and subsequently apply the algorithms to data from nuclear magnetic resonance spin-labeling experiments on the Delta 131 Delta fragment of Staphylococcal nuclease. A significant strength of the procedure that we present is that it directly uses experimental data to optimize the energy parameters, without relying on the availability of high resolution structures. The procedure is fully general and can be applied to a range of experimental data and energy functions ...

2008-01-01

167

Experimental and theoretical investigation of amino acids dimers and associates adsorption on carbon surface  

British Library Electronic Table of Contents (United Kingdom)

The thermodynamic characteristics of adsorption (the Henry constant, the heat and entropy of adsorption) of amino acids associates with acetic, trifluoroacetic, nonafluoropentanoic acids and formamide with different values of hydrogen bond lengths and various conformations on a graphitized thermal carbon black (GTCB) were calculated. The experimental results, as the Henry constant, lnK1, and the differences in the molar Gibbs energies, d(DG), obtained by a high performance liquid chromatography (HPLC) on a carbon sorbent Hypercarb, were compared with the values of thermodynamic characteristics of adsorption of the amino acids on the GTCB surface calculated by a molecular-statistical method. A satisfactory correlation was observed between the experimental and calculated values with a coeffi...

2011-01-01

168

Exciplex processes involving trans naphthylethylenes. Implications of ground-state conformeric equilibria  

Energy Technology Data Exchange (ETDEWEB)

Five arylethylenes with 1-naphthyl, 2-naphthyl, and phenyl groups in 1,2-positions have been studied for singlet-mediated charge-transfer interactions with several amines and paraquat dication. 1-Phenyl-2-(2-naphthyl)ethylene and 1,2-di(2-naphthyl)ethylene exhibit distinct dependence of exciplex emission maxima and lifetimes, and fluorescence quenching constants, on excitation and/or monitoring wavelengths; this is in conformity with the existence of ground-state rotamers for these systems, wtih distinguishable absorption-emission spectra and fluorescence lifetimes. The fluorescence quenching by aromatic amines and paraquat dication occurs with rate constants in the limit of diffusion control and is accompanied by the formation of radical ions in polar solvents (acetonitrile). The transient spectra and kinetics associated with the radical ions, observed by 337.1- and 355-nm laser flash photolysis, are also reported. 10 figures, 4 tables.

1983-05-12

169

Energy value as a factor of agroforestry wood species selectivity in Akinyele and Ido local government areas of Oyo State, Nigeria  

British Library Electronic Table of Contents (United Kingdom)

Wood usage for cooking and heating is still very relevant in most developing countries especially those of sub-Saharan Africa and many parts of Asia. Therefore, sustainable means of generating it for this and other purposes are necessary bearing in mind the influence of indigenous knowledge/users perspective on any production method regarding success and sustenance. In conformity with this view, questionnaires were administered on 240 respondents in 8 rural communities of Akinyele and Ido Local Government Areas (LGAs) of Oyo State, Nigeria, to elicit information on species that can be used as fuelwood, preferred by the respondents for incorporation into and/or retention in agroforestry plots, out of which 179 (i.e. 75% of the total number of questionnaires administered) were successfully r...

2009-01-01

170

Effect of strongly coupled plasma on the spectra of hydrogenlike carbon, aluminium and argon  

Science.gov (United States)

A detailed study has been performed for estimating the orbital energies, positions and shifts of the Lyman lines of C5+, Al12+ and Ar17+ under strongly coupled plasma with a view to understand such line positions and shifts obtained in laser produced plasma experiments. The effect of strongly coupled plasma has been treated within the Ion Sphere (IS) model. Both non-relativistic and relativistic methods have been used for estimating the spectral properties. Theoretical estimates with IS model of the plasma are in conformity with the results of laser plasma experiments on these highly stripped ions. The experimental data for the systems have also been compared with the theoretical estimates using Debye screening model of the plasma with spatial confinements which gives additional restrictions to the wave functions at finite boundaries.

2008-01-01

171

Diphtheria toxoid conformation in the context of its nanoencapsulation within liposomal particles sandwiched by chitosan  

British Library Electronic Table of Contents (United Kingdom)

Chitosan (a?-(1-4)-amino-2-deoxy-b?-D-glucan) is a deacetylated form of chitin, a polysaccharide from crustacean shells. Its unique characteristics, such as positive charge, biodegradability, biocompatibility, nontoxicity, and rigid structure, make this macromolecule ideal for an oral vaccine delivery system. We prepared reverse-phase evaporation vesicles (REVs) sandwiched by chitosan (Chi) and polyvinylic alcohol (PVA). However, in this method, there are still some problems to be circumvented related to protein stabilization. During the inverted micelle phase of protein nanoencapsulation, hydrophobic interfaces are expanded, leading to interfacial adsorption, followed by protein unfolding and aggregation. Here, spectroscopic and immunological techniques were used to ascertain the effects ...

2011-01-01

172

Development of sealing insulator for electric penetration assemblies  

International Nuclear Information System (INIS)

Electrical penetration assemblies mounted on the containment wall are used to carry electrical power and signals from the equipment inside this containment (e.g. recirculation pumps, control rod position indications etc.) Todays BWR nuclear power plants apply epoxy resin sealed electric penetration. Contrariwise, the epoxy resin (organic sealant) was replaced with sodium barium glass (inorganic) by way of trial in search for a quality sealant. The glass sealant has been proved to have high temperature airtightness at 300 degC above from an evaluation test involving full-scale model parts. Environmental tests were conducted continuously as to heat cycle, vibration and LOCA etc. the specimens (module) of five types. They were made certain of conformity to the design requirements for boiling water operation. (author).

173

Design and field trial application of foam in production wells to improve conformance  

Energy Technology Data Exchange (ETDEWEB)

The experimental foam treatments conducted on two production wells, each in a different miscible flood pool, were described, including aspects of the laboratory work, numerical coning simulation, well selection process and foam placement strategy. One of the wells was injected with a foam-forming surfactant, as well as with a surface-generated preformed foam. Neither of these treatments had any effect on the performance of this well. In the other well, preformed foam treatment was successful in reducing gas-oil ratio, resulting in improved oil production over a 14-month period. Future foam injection projects are being planned, based on the experiences gained in this field experiment. 13 refs., 21 figs.

1997-02-01

174

Design and field trial application of foam in production wells to improve conformance  

Energy Technology Data Exchange (ETDEWEB)

Many of the vertical hydrocarbon miscible floods in the Keg River carbonate reefs of the Rainbow Field are at a mature stage of reservoir depletion, and are characterized by thin oil sandwiches. Injection of a gas-blocking foam barrier into a gas cone had the potential to improve oil productivity. Experimental foam treatments were described for two wells, each in a different miscible flood well. One of the wells received foam in an aqueous solution to generate foam in-situ, and as a surface generated foam. These attempt were unsuccessful at improving well performance. The second well was injected with preformed foam only. This treatment reduced GOR and improved oil production over a 14 month period. Field experience from these field trials was expected to improve efficiency in planning, design, implementation and evaluation of future foam projects.

1995-05-01

175

Conjugate variables in quantum field theory: the basic case  

CERN Document Server

Within standard quantum field theory of one scalar field we define operators conjugate to the energy-momentum operators of the theory. They are singled out by calculational simplicity in Fock space. In terms of the underlying scalar field they are non-local. We establish their algebra where it turns out that time and space operators do not commute. Their transformation properties with respect to the conformal group are derived. Solving their eigenvalue problem permits to reconstruct the Fock space in terms of the eigenstates. It is indicated how Paulis theorem may be circumvented. As an application we form the analogue of S-matrices which yields information on the structure of the underlying spacetime. Similarly we define fields and look at their equations of motion.

2010-01-01

176

Circular map for supercavitating flow in a multiply connected domain  

British Library Electronic Table of Contents (United Kingdom)

A nonlinear free boundary-value problem of supercavitating flow past n + 1 hydrofoils is analyzed. To describe the cavities' closure mechanism, the Tulin-Terentev single-spiral-vortex model is employed. The flow domain is considered as the image of an (n + 1)-connected circular domain. The conformal map is constructed in terms of the solutions to two Riemann-Hilbert problems of the theory of symmetric automorphic functions. One of the problems is homogeneous and its coefficients are continuous functions while the second problem is inhomogeneous and has discontinuous coefficients. The exact solutions to the problems are found by using quasiautomorphic and quasimultiplicative analogs of the Cauchy kernel. The case of a single plate is considered in detail and the numerical results are report...

2009-01-01

177

Chemical Analysis of Solid-State Irradiated Human Insulin  

British Library Electronic Table of Contents (United Kingdom)

Purpose To study the chemical modifications induced upon irradiation of solid human insulin at radiosterilization doses and investigate the influence of the absorbed dose on radiolysis. Materials and Methods Volatile radiolytic products were monitored by gas chromatography coupled with mass spectrometry (GC-MS) and non-volatile products by two different high performance liquid chromatography (HPLC) methods: the formation of higher molecular weight proteins was assessed by size exclusion liquid chromatography whereas assays for related compounds and chemical potency tests were carried out using reverse-phase HPLC-UV. Conformational changes were investigated by measurements of circular dichroism. Results After gamma irradiation at 10?kGy, the recovery of insulin was 96.8%; higher molecular w...

2006-01-01

178

Biological treatment of wine of distilleries  

International Nuclear Information System (INIS)

The potential of the yeast Candida tropicalis and Candida guillermondii was evaluated and an isolated partnership of microorganisms of waters of the Medellin River, conformed by two bacteria and one leavening, to degrade the content of organic matter present in wine produced by the factory of Licores and Alcoholes de Antioquia (FLA) in aerobic process with biomass production. For each one of the microorganisms in study this capacity of removal in units of chemical demand of oxygen was quantified (CDO); in addition, parameters were analyzed such as yield of the biomass in relation to the removed CDO and to total reducing sugars (TRS) consumed, time of fermentation and speed of growth different dilutions from wine. Also the possible inhibition was analyzed that the present phenolic compounds in this wine can cause in the biological process of degradation.

179

Bacteriophage P22 capsid size determination: Roles for the coat protein telokin-like domain and the scaffolding protein amino-terminus  

British Library Electronic Table of Contents (United Kingdom)

Assembly of icosahedral capsids of proper size and symmetry is not understood. Residue F170 in bacteriophage P22 coat protein is critical for conformational switching during assembly. Substitutions at this site cause assembly of tubes of hexamerically arranged coat protein. Intragenic suppressors of the ts phenotype of F170A and F170K coat protein mutants were isolated. Suppressors were repeatedly found in the coat protein telokin-like domain at position 285, which caused coat protein to assemble into petite procapsids and capsids. Petite capsid assembly strongly correlated to the side chain volume of the substituted amino acid. We hypothesize that larger side chains at position 285 torque the telokin-like domain, changing flexibility of the subunit and intercapsomer contacts. Thus, a sing...

2011-01-01

180

Assuring both quality and creativity in basic research  

Energy Technology Data Exchange (ETDEWEB)

How does one assure that both quality and creativity are obtained in basic research environments QA theoreticians have attempted to develop workable definitions of quality, but in more reflective moments, these definitions often fail to capture the deeper essence of the idea of quality.'' This paper asserts that creativity (as a product of the human mind) is a concrete interface between perfunctory definitions of quality (conformance to specifications) and more philosophical speculations about the nature of quality- related ultimates'' like elegance or beauty. In addition, we describe the distinction between creative ideas and creative acts and highlight one of the major inhibitors of creativity, fear. Finally we show that highly creative people often have an irreverent attitude toward boundaries and established authority, and discuss how one can allow for this when designing a QA program in a basic research environment.

1990-04-12

181

Assessment of GABARAP self-association by its diffusion properties  

Energy Technology Data Exchange (ETDEWEB)

Gamma-aminobutyric acid type A receptor-associated protein (GABARAP) belongs to a family of small ubiquitin-like adaptor proteins implicated in intracellular vesicle trafficking and autophagy. We have used diffusion-ordered nuclear magnetic resonance spectroscopy to study the temperature and concentration dependence of the diffusion properties of GABARAP. Our data suggest the presence of distinct conformational states and provide support for self-association of GABARAP molecules. Assuming a monomer-dimer equilibrium, a temperature-dependent dissociation constant could be derived. Based on a temperature series of {sup 1}H{sup 15}N heteronuclear single quantum coherence nuclear magnetic resonance spectra, we propose residues potentially involved in GABARAP self-interaction. The possible biological significance of these observations is discussed with respect to alternative scenarios of oligomerization.

2010-09-15

182

Adaptive Radiation Therapy for Localized Mesothelioma with Mediastinal Metastasis Using Helical Tomotherapy  

British Library Electronic Table of Contents (United Kingdom)

The purpose of this study was to compare 2 adaptive radiotherapy strategies with helical tomotherapy. A patient having mesothelioma with mediastinal nodes was treated using helical tomotherapy with pretreatment megavoltage CT (MVCT) imaging. Gross tumor volumes (GTVs) were outlined on every MVCT study. Two alternatives for adapting the treatment were investigated: (1) keeping the prescribed dose to the targets while reducing the dose to the OARs and (2) escalating the target dose while maintaining the original level of healthy tissue sparing. Intensity modulated radiotherapy (step-and-shoot IMRT) and 3D conformal radiotherapy (3DCRT) plans for the patient were generated and compared. The primary lesion and nodal mass regressed by 16.2% and 32.5%, respectively. Adapted GTVs and reduced plan...

2009-01-01

183

A retrospective study of canine hip dysplasia in 116 military workingn> dogs. Part I: Angle measurements and orthopedic foundation for animals (OFA) grading.  

Science.gov (United States)

The progression of hip dysplasia was investigated in 116 military working dogs. Serial pelvic radiographs were graded for degree of dysplasia and degenerative joint disease (DJD). Norberg angles, angles of inclination, and joint space widths were measured. There was a significant correlation between the Norberg angle and the degree of dysplasia (p less than 0.0001). Angles of inclination and joint space width measurements did not demonstrate a correlation to canine hip dysplasia. Dysplastic dogs had a significant estimated risk for development of DJD compared to normal dogs (p less than 0.0001; odds ratio of 70.2). Dogs with normal hip conformation at 24 months of age or older did not develop moderate nor severe DJD. PMID:8875357

184

Photophysical properties of new psoralen derivatives: psoralens linked to adenine through polymethylene chains  

International Nuclear Information System (INIS)

The model compounds, 8-methoxypsoralen-CH_2O(CH_2)_n-adenine (MOPCH_2OC_nAd, n=2,3,5,6,8, and 10) in which 5 position of 8-methoxypsoralen (8-MOP) is linked by various lengths of polymethylene bridge to N"9 of adenine. UV absorption spectra are identical with the sum of MOPCH_2OC3 and adenine absorption spectra. Solvent effect on the UV absorption and fluorescence emission spectra indicate that the lowest excited singlet state is the (#pi##->##pi#"*) state. The spectral characteristics of the fluorescence of MOPCH_2OC_nAd are strongly dependent upon the nature of the solvents. The fluorescence emission spectra in aprotic solvents are broad and structrueless due to the excimer formation through the folded conformation accelerated by hydrophobic #pi#-#pi# stacking interaction. Increasing polarity of the protic solvents leads to higher population of unfolded conformation stabilized through favorable solvation and H-bonding, and consequently to ...

2002-10-01

185

Enzymatic synthesis and carbon-13 nuclear magnetic resonance conformational studies of disaccharides containing. beta. -D-galactopyranosyl and. beta. -D-(1-/sup 13/C)Galactopyranosyl residues  

Energy Technology Data Exchange (ETDEWEB)

Partially purified UDPgalactosyltransferase (EC 2.4.1.22) from bovine milk has been used to synthesize millimolar amounts of compounds such as Gal..beta..(1..-->..4)Glc, Gal..beta..(1..-->..4)GlcNAc-..beta..-hexanolamine, and Gal..beta..(1..-->..4)-GlcNAc..beta..(1..-->..4)GlcNAc. The same method has been used to prepare similar compounds containing /sup 13/C-enriched galactopyranosyl moieties. Gal..beta..(1..-->..4)GlcNAc-..beta..-hexanolamine was also synthesized in a solid-phase system in which the GlcNAc-..beta..-hexanolamine glycoside was covalently linked to agarose beads. At pH 7.0 and at 1 to 5 mM Mn/sup 2 + +/ the yields of the galactosyl saccharides are greater than 90% by using 10% excess of UDPGal donor. The use of a 90% enriched (1-/sup 13/C)galactosyl residue allowed the determination of the most abundant conformer about the galactopyranosyl-glycoside linkage by analysis of the carbon-carbon coupling constants from Cl to Gal to the ...

1980-02-05

186

Concurrent and adjuvant docetaxel with three-dimensional conformal radiation therapy plus androgen deprivation for high-risk prostate cancer: Preliminary results of a multicentre phase II trial  

International Nuclear Information System (INIS)

Background and purpose: We evaluate the feasibility of concomitant and adjuvant docetaxel combined with three-dimensional conformal radiotherapy (3D-CRT) and androgen deprivation in high-risk prostate carcinomas. Methods: Fifty men with high-risk localized prostate cancer (16), locally advanced (28) or very high-risk prostate cancer (6) were included. Seventy Gy were delivered on prostate and seminal vesicles in 35 fractions, concurrently with weekly docetaxel (20 mg/m"2). Three weeks after the completion of 3D-CRT, docetaxel was given for 3 cycles (60 mg/m"2), every 3 weeks. Patients had to receive LHRH agonist during 3 years. Results: The intent to treat analysis shows that four patients out of 15 stopped prematurely the chemotherapy due to grade 3-4 acute toxicity. In the per protocol analysis, 46 patients completed a full-dose chemoradiation regimen representing 413 cycles: five patients experienced a grade 3 toxicity, and 15 patients experienced a grade 2 ...

2010-11-01

187

Can intensity-modulated radiation therapy of the paraaortic region overcome the problems of critical organ tolerance?  

International Nuclear Information System (INIS)

Background and purpose: the recent RTOG guidelines for future clinical developments in gynecologic malignancies included the investigation of dose escalation in the paraaortic (PO) region which is, however, very difficult to target due to the presence of critical organs such as kidneys, liver, spinal cord, and digestive structures. The aim of this study was to investigate intensity-modulated radiotherapy's (IMRT) possibilities of either increasing, in a safe way, the dose to 50-60 Gy in case of macroscopic disease or decreasing the dose to organs at risk (OR) when treatment is given in an adjuvant setting. Material and methods: the dosimetric charts of 14 patients irradiated to the PO region at the department of radiation oncology, university hospital of Liege, Belgium, in 2000 were analyzed in order to compare six-field conformal external-beam radio-therapy (CEBR) and five-beam IMRT approaches. Both CEBR and IMRT investigations were planned to theoretically ...

2005-03-01

188

Architectural design criteria for f-block metal ion sequestering agents. 1998 annual progress report  

Energy Technology Data Exchange (ETDEWEB)

'The objective of this project is to provide a means to optimize ligand architecture for f-block metal recognition. The authors strategy builds on an innovative and successful molecular modeling approach in developing polyether ligand design criteria for the alkali and alkaline earth cations. The hypothesis underlying this proposal is that differences in metal ion binding with multidentate ligands bearing the same number and type of donor groups are primarily attributable to intramolecular steric factors. They propose quantifying these steric factors through the application of molecular mechanics models. The research involves close integration of theoretical and experimental chemistry. The experimental work entails synthesizing novel ligands and experimentally determining structures and binding constants for metal ion complexation by series of ligands in which architecture is systematically varied. The theoretical work entails using electronic structure calculations to ...

1998-12-31

189

Antihuman growth hormone (GH) antibodies cross-react with the GH-like factor from plerocercoids of the tapeworm Spirometra mansonoides.  

Science.gov (United States)

A factor produced by the plerocercoid stage of S. mansonoides mimics some, but not all, of the actions reported for hGH. The biological actions of plerocercoid growth factor (PGF) suggest structural similarity to human GH (hGH). Plerocercoid membranes were solubilized, and PGF was purified more than 1000-fold by hGH receptor affinity chromatography. The ability of purified PGF to displace [125I]hGH from monoclonal antibodies specific for four distinct nonoverlapping antigenic determinants of hGH and from an anti-hGH polyclonal antibody was tested in liquid phase RIA. All of the hGH antibodies cross-reacted with PGF, with potencies ranging from more than 60% to less than 1% that of the hGH standard. Of the four major epitopes of hGH defined by the monoclonal antibodies used in this study, only one is not represented to a significant extent in PGF. The epitope of hGH that is only marginally present in PGF is highly conformationally dependent, and a minor difference ...

1987-11-01

190

An iterative filtered backprojection inverse treatment planning algorithm for tomotherapy  

International Nuclear Information System (INIS)

Purpose: An inverse treatment planning algorithm for tomotherapy is described. Methods and Materials: The algorithm iteratively computes a set of nonnegative beam intensity profiles that minimizes the least-squares residual dose defined in the target and selected normal tissue regions of interest. At each iteration the residual dose distribution is transformed into a set of residual beam profiles using an inversion method derived from filtered backprojection image reconstruction theory. These 'residual' profiles are used to correct the current beam profile estimates resulting in new profile estimates. Adaptive filtering is incorporated into the inversion model so that the gross structure of the dose distribution is optimized during initial iterations of the algorithm, and the fine structure corresponding to edges is obtained at later iterations. A three dimensional, kernel based, convolution/superposition dose model is used to compute dose during each iteration. Results: Two clinically ...

1995-07-15

191

cDNA-AFLP analysis reveals differential gene expression in compatible interaction of wheat challenged with Puccinia striiformis f. sp. tritici  

UK PubMed Central (United Kingdom)

BackgroundPuccinia striiformis f. sp. tritici is a fungal pathogen causing stripe rust, one of the most important wheat diseases worldwide. The...Full Text Available

192

Virtual adult ears reveal the roles of acoustical factors and experience in auditory space map development  

UK PubMed Central (United Kingdom)

Auditory neurons in the superior colliculus (SC) respond preferentially to sounds from restricted directions to form a map of auditory space. The development of this representation is shaped...Full Text Available

2008-11-05

193

Use of Forward Genetics to Discover Novel Regulators of NF-?B  

UK PubMed Central (United Kingdom)

Forward and reverse genetic experiments have both played important roles in revealing critical aspects of mammalian signal transduction pathways in cell culture experiments. Only recently have we begun...Full Text Available

2010-06-01

194

Understanding the nature of the statistics behind energy-related CO{sub 2} emissions  

Energy Technology Data Exchange (ETDEWEB)

Research reported here reveals that the reduction of CO{sub 2} emissions into the atmosphere, is mainly dependent on the decrease of the use of fossil fuels, but also on the development of environment-friendly technology and greening of the environment. 2 refs.

2001-07-01

195

Transcriptome Profiling of a Toxic Dinoflagellate Reveals a Gene-Rich Protist and a Potential Impact on Gene Expression Due to Bacterial Presence  

UK PubMed Central (United Kingdom)

BackgroundDinoflagellates are unicellular, often photosynthetic protists that play a major role in the dynamics of the Earth's oceans and climate. Sequencing of dinoflagellate nuclear...Full Text Available

196

Transcriptional mapping of the 3' end of the bovine syncytial virus genome.  

UK PubMed Central (United Kingdom)

The bovine syncytial virus, a member of the retroviral subfamily Spumavirinae, causes a persistent, asymptomatic infection in cattle. Nucleotide sequence analysis of the viral genome revealed two overlapping...Full Text Available

1994-02-01

197

Thermal dislocation depinning in a deformed crystal  

Energy Technology Data Exchange (ETDEWEB)

The temperature dependence of the dislocation mobility threshold is investigated on the basis of a dislocation model suggested by Frenkel-Kontorova. The critical value is obtained for the stress/temperature, corresponding to the dislocation depinning from its equilibrium position. The universal behaviour of a barrier height at finite stress and temperature is revealed and investigated.

2008-01-14

198

The role of skin absorption as a route of exposure for volatile organic compounds (VOCs) in drinking water.  

UK PubMed Central (United Kingdom)

Assessments of drinking water safety rely on the assumption that ingestion represents the principal route of exposure. A review of the experimental literature revealed that skin penetration rates for...Full Text Available

1984-05-01

199

The effects of high voltage transmission lines on the health of adjacent resident populations.  

UK PubMed Central (United Kingdom)

A community health survey of 438 individuals was taken to detect health problems related to high voltage electrical transmission among an adjacent residential population. Results revealed no significant...Full Text Available

1984-01-01

200

The complexity of gene expression dynamics revealed by permutation entropy  

UK PubMed Central (United Kingdom)

BackgroundHigh complexity is considered a hallmark of living systems. Here we investigate the complexity of temporal gene expression patterns using the concept of Permutation Entropy...Full Text Available

201

The Structure of the Dust Mite Allergen Der p 7 Reveals Similarities to Innate Immune Proteins  

UK PubMed Central (United Kingdom)

BackgroundSensitization to house dust mite allergens is strongly correlated with asthma. Der p 7 elicits strong IgE antibody and T-cell responses in mite allergic...Full Text Available

2010-04-01

202

The Development and Evolution of Division of Labor and Foraging Specialization in a Social Insect (Apis mellifera L.)  

UK PubMed Central (United Kingdom)

How does complex social behavior evolve? What are the developmental building blocks of division of labor and specialization, the hallmarks of insect societies? Studies have revealed the developmental...Full Text Available

2006-01-01

203

Ternary Complex Formation on the Adenovirus Packaging Sequence by the IVa2 and L4 22-Kilodalton Proteins?  

UK PubMed Central (United Kingdom)

Assembly of infectious adenovirus particles requires seven functionally redundant elements at the left end of the genome, termed A repeats, that direct packaging of the DNA. Previous studies revealed...Full Text Available

2007-11-01

204

Studies on the mechanism of 1,3-butadiene-induced leukemogenesis: the potential role of endogenous murine leukemia virus.  

UK PubMed Central (United Kingdom)

Previous studies have revealed marked differences in the incidence of leukemia between rats and mice exposed to 1,3-butadiene that do not appear to be readily explained on the basis of pharmacokinetics...Full Text Available

1990-06-01

205

Student Understanding of the First and Second Laws of Thermodynamics  

Science.gov (United States)

This presentation from the 2006 PTEC Conference presents education research on topics in thermodynamics. Student responses to conceptual thermodynamics questions, and the conceptions they reveal, are presented. Tutorial materials developed to help students gain a better understanding of the topic are also presented.

2006-09-30

206

Structure of Natural Killer Cell Receptor KLRG1 Bound to E-Cadherin Reveals Basis for MHC-Independent Missing Self Recognition  

UK PubMed Central (United Kingdom)

SUMMARYThe cytolytic activity of natural killer (NK) cells is regulated by inhibitory receptors that detect the absence of self molecules on target cells. Structural studies of...Full Text Available

2009-07-17

207

Stable Isotopes (?D, ?13C, ?15N) Reveal Associations Among Geographic Location and Condition of Alaskan Northern ...  

Science.gov (United States)

... M. Taylor, T. Kurt Kyser. (2009) Feather isotope analysis discriminates age-classes of Western, Least, and Semipalmated sandpipers when plumage ... ...

208

Squamous Cell Carcinoma in South-Eastern Equatorial Rain Forest in Calabar, Nigeria  

UK PubMed Central (United Kingdom)

Background: In North America and Europe, 80% of invasive skin cancers are basal cell carcinoma while 20% are squamous cell carcinoma (SCC). In contrast, African studies reveal a preponderance...Full Text Available

209

Spontaneous Cortical Activity Reveals Hallmarks of an Optimal Internal Model of the Environment *  

UK PubMed Central (United Kingdom)

The brain maintains internal models of its environment to interpret sensory inputs and prepare actions. While behavioral studies demonstrated that these internal models are optimally adapted...Full Text Available

2011-01-07

210

Soluble epoxide hydrolase inhibition reveals novel biological functions of epoxyeicosatrienoic acids (EETs)  

UK PubMed Central (United Kingdom)

Early on, intriguing biological activities were found associated with the EETs using in vitro systems. Although the EETs other than the 5,6-isomer, are quite stable chemically,...Full Text Available

2007-01-01

211

Sequence and expression of the zebrafish alpha-actinin gene family reveals conservation and diversification among vertebrates  

UK PubMed Central (United Kingdom)

alpha-actinins are actin microfilament crosslinking proteins. Vertebrate actinins fall into two classes: the broadly-expressed actinins 1 and 4 (actn1 and actn4)...Full Text Available

2009-11-01

212

Select spinal lesions reveal multiple ascending pathways in the rat conveying input from the male genitalia  

UK PubMed Central (United Kingdom)

The specific white matter location of all the spinal pathways conveying penile input to the rostral medulla is not known. Our previous studies using rats demonstrated the loss of low but not high threshold...Full Text Available

2010-04-01

213

Seasonal proteomic changes reveal molecular adaptations to preserve and replenish liver proteins during ground squirrel hibernation  

UK PubMed Central (United Kingdom)

Hibernators are unique among mammals in their ability to survive extended periods of time with core body temperatures near freezing and with dramatically reduced heart, respiratory, and metabolic rates...Full Text Available

2010-02-01

214

STRUCTURE OF THE MACULA UTRICULI WITH SPECIAL REFERENCE TO DIRECTIONAL INTERPLAY OF SENSORY RESPONSES AS REVEALED BY MORPHOLOGICAL POLARIZATION  

UK PubMed Central (United Kingdom)

The anatomy of the labyrinth and the structure of the macula utriculi of the teleost fish (burbot) Lota vulgaris was studied by dissection, phase contrast, and electron microscopy....Full Text Available

1964-08-01

215

Role of Conserved Salt Bridges in Homeodomain Stability and DNA Binding*  

UK PubMed Central (United Kingdom)

The sequence information available for homeodomains reveals that salt bridges connecting pairs 19/30, 31/42, and 17/52 are frequent, whereas aliphatic residues at these sites are rare and mainly restricted...Full Text Available

2009-08-28

216

Risks of consumption of contaminated seafood: the Quincy Bay case study.  

UK PubMed Central (United Kingdom)

A recent EPA-sponsored study of sediment and seafood contamination in Quincy Bay revealed elevated levels of several complex organic pollutants frequently of concern in human health assessments. A seafood...Full Text Available

1991-01-01

217

Right flank laparotomy and abomasotomy for removal of a phytobezoar in a standing cow  

UK PubMed Central (United Kingdom)

A 4.5-year-old Holstein-Friesian cow underwent surgery because of left abomasal displacement. Intra-operative palpation of the pyloric region revealed a phytobezoar. The abomasum containing the phytobezoar...Full Text Available

2010-07-01

218

Relationship between mRNA secondary structure and sequence variability in Chloroplast genes: possible life history implications  

UK PubMed Central (United Kingdom)

BackgroundSynonymous sites are freer to vary because of redundancy in genetic code. Messenger RNA secondary structure restricts this freedom, as revealed by previous findings in...Full Text Available

219

Reconstruction of the complete human cytomegalovirus genome in a BAC reveals RL13 to be a potent inhibitor of replication  

UK PubMed Central (United Kingdom)

Human cytomegalovirus (HCMV) in clinical material cannot replicate efficiently in vitro until it has adapted by mutation. Consequently, wild-type HCMV differ fundamentally from the passaged strains...Full Text Available

2010-09-01

220

RNA expression in a cartilaginous fish cell line reveals ancient 3? noncoding regions highly conserved in vertebrates  

UK PubMed Central (United Kingdom)

We have established a cartilaginous fish cell line [Squalus acanthias embryo cell line (SAE)], a mesenchymal stem cell line derived from the embryo of an elasmobranch, the spiny dogfish...Full Text Available

2007-01-23

221

Pyogenic Spondylodiscitis after Percutaneous Endoscopic Lumbar Discectomy  

UK PubMed Central (United Kingdom)

We reviewed 9 cases of pyogenic spondylodiscitis following percutaneous endoscopic lumbar discectomy (PELD). Microbiologic cultures revealed 6 causative organisms. Five patients were managed conservatively...Full Text Available

2010-11-01

222

Physique and Serum Lipids of Young London Busmen in relation to Ischaemic Heart Disease  

UK PubMed Central (United Kingdom)

Earlier studies of white London busmen revealed that the ischaemic heart disease experience of conductors is better than that of drivers. Various factors which might be related to this difference have...Full Text Available

1967-07-01

223

Oxygen-dependent catabolism of indole-3-acetic acid in Bradyrhizobium japonicum.  

UK PubMed Central (United Kingdom)

Some strains of Bradyrhizobium japonicum have the ability to catabolize indole-3-acetic acid (IAA). Examination of this catabolism in strain 110 by in vivo experiments has revealed an enzymatic activity...Full Text Available

1991-08-01

224

Nitric Oxide-Mediated Tumoricidal Activity of Murine Microglial Cells12  

UK PubMed Central (United Kingdom)

Experimental metastases in the brain of mice are infiltrated by microglia, and parabiosis experiments of green fluorescent protein (GFP+) and GFP- mice revealed that these microglia...Full Text Available

225

Natural selection and the molecular basis of electrophoretic variation at the coagulation F13B locus  

UK PubMed Central (United Kingdom)

Electrophoretic analysis of protein variation at the coagulation F13B locus has previously revealed three alleles, with alleles 1, 2, and 3 each being at high frequency in European,...Full Text Available

2009-02-01

226

Mycobacterium tuberculosis Chaperonin 10 Is Secreted in the Macrophage Phagosome: Is Secretion Due to Dissociation and Adoption of a Partially Helical Structure at the Membrane?  

UK PubMed Central (United Kingdom)

To confirm that Mycobacterium tuberculosis chaperonin 10 (Cpn10) is secreted outside the live bacillus, infected macrophages were examined by electron microscopy. This revealed that...Full Text Available

2003-07-01

227

Multivariate analyses reveal common and drug specific genetic influences on responses to four drugs of abuse  

UK PubMed Central (United Kingdom)

Vulnerability to abused drugs is influenced by multiple genes unique to each drug as well as to risk genes for polydrug abuse. If several inbred mouse strains respond to different drugs similarly,...Full Text Available

2008-11-01

228

Mapping Drug Physico-Chemical Features to Pathway Activity Reveals Molecular Networks Linked to Toxicity Outcome  

UK PubMed Central (United Kingdom)

The identification of predictive biomarkers is at the core of modern toxicology. So far, a number of approaches have been proposed. These rely on statistical inference of toxicity response from either...Full Text Available

229

Lethal protein produced in response to competition between sibling bacterial colonies  

UK PubMed Central (United Kingdom)

Sibling Paenibacillus dendritiformis bacterial colonies grown on low-nutrient agar medium mutually inhibit growth through secretion of a lethal factor. Analysis of secretions reveals...Full Text Available

2010-04-06

230

Kaposi's sarcoma involving the thyroid in a patient with AIDS  

International Nuclear Information System (INIS)

A 30-year-old man with acquired immune deficiency syndrome (AIDS) and Kaposi's sarcoma had a palpable thyroid mass and cervical lymphadenopathy. Nuclear medicine and ultrasound scans revealed multiple thyroid nodules. Results of biopsy showed Kaposi's sarcoma metastatic to the thyroid.

231

JAK/STAT Pathways in Cytokine Signaling and Myeloproliferative Disorders  

UK PubMed Central (United Kingdom)

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

2010-10-01

232

Isolation, sequence analysis, and physiological properties of enkephalins in the nervous tissue of the shore crab Carcinus maenas L.  

UK PubMed Central (United Kingdom)

[Leu]- and [Met]enkephalin from thoracic ganglia of the shore crab Carcinus maenas have been purified to homogeneity by a reversed-phase HPLC procedure. Automated gas-phase sequencing revealed a primary...Full Text Available

1991-10-01

233

Insights into the Genome of Large Sulfur Bacteria Revealed by Analysis of Single Filaments  

UK PubMed Central (United Kingdom)

Marine sediments are frequently covered by mats of the filamentous Beggiatoa and other large nitrate-storing bacteria that oxidize hydrogen sulfide using either oxygen or nitrate, which...Full Text Available

2007-09-01

234

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

235

Genomic patterns of pathogen evolution revealed by comparison of Burkholderia pseudomallei, the causative agent of melioidosis, to avirulent Burkholderia thailandensis  

UK PubMed Central (United Kingdom)

BackgroundThe Gram-negative bacterium Burkholderia pseudomallei (Bp) is the causative agent of the human disease melioidosis. To understand the evolutionary mechanisms...Full Text Available

236

Genomic Diversity and Evolution of Mycobacterium ulcerans Revealed by Next-Generation Sequencing  

UK PubMed Central (United Kingdom)

Mycobacterium ulcerans is the causative agent of Buruli ulcer, the third most common mycobacterial disease after tuberculosis and leprosy. It is an emerging infectious disease that...Full Text Available

2009-09-01

237

Genome-wide expression profiling reveals distinct clusters of transcriptional regulation during bovine preimplantation development in vivo  

UK PubMed Central (United Kingdom)

Bovine embryos can be generated by in vitro fertilization or somatic nuclear transfer; however, these differ from their in vivo counterparts in many aspects and exhibit a higher proportion of developmental...Full Text Available

2008-12-16

238

Genome-Wide Analysis Reveals a Major Role in Cell Fate Maintenance and an Unexpected Role in Endoreduplication for the Drosophila FoxA Gene Fork Head  

UK PubMed Central (United Kingdom)

Transcription factors drive organogenesis, from the initiation of cell fate decisions to the maintenance and implementation of these decisions. The Drosophila embryonic salivary gland...Full Text Available

239

Gene-silencing reveals the functional significance of pheromone biosynthesis activating neuropeptide receptor (PBAN-R) in a male moth  

UK PubMed Central (United Kingdom)

The role of pheromone biosynthesis activating neuropeptide (PBAN) in the regulation of pheromone biosynthesis of several female moth species is well elucidated, but its role in the males has been a...Full Text Available

2010-09-28

240

Gene expression profile of rat left ventricles reveals persisting changes following chronic mild exercise protocol: implications for cardioprotection  

UK PubMed Central (United Kingdom)

BackgroundEpidemiological studies showed that physical exercise, specifically moderate lifelong training, is protective against cardiovascular morbidity and mortality. Most experimental...Full Text Available

241

Fourier-Domain Optical Coherence Tomography and Adaptive Optics Reveal Nerve Fiber Layer Loss and Photoreceptor Changes in a Patient With Optic Nerve Drusen  

UK PubMed Central (United Kingdom)

BackgroundNew technology allows more precise definition of structural alterations of all retinal layers although it has not been used previously in cases of optic...Full Text Available

2008-06-01

242

Effects of Sodium Pentobarbital Anesthesia and Leukocytosis on 'Escherichia coli' Mortality in Dog Blood 'In vitro'.  

Science.gov (United States)

Data reveal that sodium pentobarbital anesthesia does not depress glucose uptake of neutrophils stimulated by the addition of live E. coli. E. coli viability was reduced equally in blood obtained before and after sodium pentobarbital anesthesia. Pre- and ...

1978-01-01

243

Effect of Feeding Cows Genetically Modified Maize on the Bacterial Community in the Bovine Rumen?  

UK PubMed Central (United Kingdom)

Rumen-cannulated cows (n = 4) were fed successively silage made from either conventional or genetically modified (GM) maize. Results revealed no effects of GM maize on the dynamics...Full Text Available

2007-12-01

244

Duration of human singleton pregnancies in Ibadan, Nigeria.  

UK PubMed Central (United Kingdom)

Analysis of gestation length in an obstetric population of indigenous African women revealed a mean pregnancy duration of 274.8 days, which is similar to values recorded in women of African descent...Full Text Available

1997-09-01

245

Downstream genes of Pax6 revealed by comprehensive transcriptome profiling in the developing rat hindbrain  

UK PubMed Central (United Kingdom)

BackgroundThe transcription factor Pax6 is essential for the development of the central nervous system and it exerts its multiple functions by regulating the expression of downstream...Full Text Available

246

Distinct signatures of diversifying selection revealed by genome analysis of respiratory tract and invasive bacterial populations  

UK PubMed Central (United Kingdom)

Many pathogens colonize different anatomical sites, but the selective pressures contributing to survival in the diverse niches are poorly understood. Group A Streptococcus (GAS) is...Full Text Available

2011-03-22

247

Determinants of antiviral treatment initiation in a hepatitis C-infected population benefiting from universal health care coverage  

UK PubMed Central (United Kingdom)

BACKGROUND AND AIMS:In view of increasing therapeutic efficacy, the delivery of hepatitis C virus (HCV) antiviral treatment is expected to increase. Yet practical experience reveals...Full Text Available

2007-06-01

248

Cytological diagnosis of a rare case of solid pseudopapillary neoplasm of the pancreas  

UK PubMed Central (United Kingdom)

A 23-year-old woman presented to our hospital with nonspecific pain in the abdomen. She underwent radiological investigations, which revealed a solid and cystic mass in the tail end of the pancreas....Full Text Available

2010-01-01

249

Coupling of Pressure-Induced Structural Shifts to Spectral Changes in a Yellow Fluorescent Protein  

UK PubMed Central (United Kingdom)

AbstractX-ray diffraction analysis of pressure-induced structural changes in the Aequorea yellow fluorescent protein Citrine reveals the structural basis for the continuous...Full Text Available

2009-09-16

250

Complexity of the microRNA repertoire revealed by next-generation sequencing  

UK PubMed Central (United Kingdom)

MicroRNAs (miRNAs) have been implicated to play key roles in normal physiological functions, and altered expression of specific miRNAs has been associated with a number of diseases. It is of great interest...Full Text Available

2010-11-01

251

Comparative transcripts profiling reveals new insight into molecular processes regulating lycopene accumulation in a sweet orange (Citrus sinensis) red-flesh mutant  

UK PubMed Central (United Kingdom)

BackgroundInterest in lycopene metabolism and regulation is growing rapidly because accumulative studies have suggested an important role for lycopene in human health promotion....Full Text Available

252

Comparative genomics reveals 104 candidate structured RNAs from bacteria, archaea, and their metagenomes  

UK PubMed Central (United Kingdom)

BackgroundStructured noncoding RNAs perform many functions that are essential for protein synthesis, RNA processing, and gene regulation. Structured RNAs can be detected by comparative...Full Text Available

2010-01-01

253

Coat protein gene duplication in a filamentous RNA virus of plants.  

UK PubMed Central (United Kingdom)

Computer-assisted analysis revealed a striking sequence similarity between the putative 24-kDa protein (p24) encoded by open reading frame (ORF) 5 of beet yellows closterovirus and the coat protein...Full Text Available

1992-10-01

254

Chromosome substitution reveals the genetic basis of Dahl salt-sensitive hypertension and renal disease  

UK PubMed Central (United Kingdom)

This study examined the genetic basis of hypertension and renal disease in Dahl SS/Mcwi (Dahl Salt-Sensitive) rats using a complete chromosome substitution panel of consomic rats in which each of the...Full Text Available

2008-09-01

255

Characterization of Two New Genes, amoR and amoD, in the amo Operon of the Marine Ammonia Oxidizer Nitrosococcus oceani ATCC 19707?  

UK PubMed Central (United Kingdom)

Molecular analysis of the amo gene cluster in Nitrosococcus oceani revealed that it consists of five genes, instead of the three known genes, amoCAB....Full Text Available

2008-01-01

256

Biochemical analysis of PIFTC3, the Trypanosoma brucei ortholog of nematode DYF-13, reveals interactions with established and putative intraflagellar transport components  

UK PubMed Central (United Kingdom)

DYF-13, originally identified in C. elegans within a collection of dye-filling chemosensory mutants, is one of several proteins that have been classified as putatively involved...Full Text Available

2010-10-01

257

Bacterial infections in suspected cutaneous leishmaniasis lesions.  

UK PubMed Central (United Kingdom)

In Iran, microscopic examination of skin scrapings from 2202 individuals with clinically diagnosed cutaneous leishmaniasis (CL) lesions revealed the presence of amastigotes in 1123 cases (51.0%). Bacteriological...Full Text Available

1990-01-01

258

Arabidopsis thaliana auxotrophs reveal a tryptophan-independent biosynthetic pathway for indole-3-acetic acid.  

UK PubMed Central (United Kingdom)

We used tryptophan auxotrophs of the dicot Arabidopsis thaliana (wall cress) to determine whether tryptophan has the capacity to serve as a precursor to the auxin, indole-3-acetic acid (IAA). Quantitative...Full Text Available

1993-11-01

259

Antagonistic Gcn5-Hda1 interactions revealed by mutations to the Anaphase Promoting Complex in yeast  

UK PubMed Central (United Kingdom)

BackgroundHistone post-translational modifications are critical for gene expression and cell viability. A broad spectrum of histone lysine residues have been identified in yeast...Full Text Available

260

Analysis of the astray/robo2 zebrafish mutant reveals that degenerating tracts do not provide strong guidance cues for regenerating optic axons  

UK PubMed Central (United Kingdom)

During formation of the optic projection in astray/robo2 mutant zebrafish, optic axons exhibit rostro-caudal pathfinding errors, ectopic midline crossing and...Full Text Available

2010-10-13

261

Adrenaline modulates the global transcriptional profile of Salmonella revealing a role in the antimicrobial peptide and oxidative stress resistance responses  

UK PubMed Central (United Kingdom)

BackgroundThe successful interaction of bacterial pathogens with host tissues requires the sensing of specific chemical and physical cues. The human gut contains a huge number of...Full Text Available

262

A non-linear approach to the structure-mobility relationship in protein main chains  

Energy Technology Data Exchange (ETDEWEB)

A correlation investigation was carried out on the series of atomic coordinates (MPV) and temperature factor (T {sub f}), respectively for human hemoglobin and HIV-1 protease protein main chains. The MPV series revealed resemblances to the corresponding T {sub f} series. Each minor or major peak in a series had a corresponding peak in the related series. This brings a qualitative evidence for the connection of the two parameters. The series were further subjected to spectral and detrended fluctuation analysis which all revealed long-range correlation properties. This combined analysis revealed that the data were controlled both by the correlation of stationary fluctuation and trends or non-stationary contribution to correlation. The correlation of all MPV series was found to be much less sensitive to ligand binding than the corresponding T {sub f} series. Thus the long-range correlation properties of the protein main chain ...

2007-05-15

263

A non-linear approach to the structure-mobility relationship in protein main chains  

International Nuclear Information System (INIS)

A correlation investigation was carried out on the series of atomic coordinates (MPV) and temperature factor (T _f), respectively for human hemoglobin and HIV-1 protease protein main chains. The MPV series revealed resemblances to the corresponding T _f series. Each minor or major peak in a series had a corresponding peak in the related series. This brings a qualitative evidence for the connection of the two parameters. The series were further subjected to spectral and detrended fluctuation analysis which all revealed long-range correlation properties. This combined analysis revealed that the data were controlled both by the correlation of stationary fluctuation and trends or non-stationary contribution to correlation. The correlation of all MPV series was found to be much less sensitive to ligand binding than the corresponding T _f series. Thus the long-range correlation properties of the protein main chain structure and ...

2007-05-01

264

A global role for KLF1 in erythropoiesis revealed by ChIP-seq in primary erythroid cells  

UK PubMed Central (United Kingdom)

KLF1 regulates a diverse suite of genes to direct erythroid cell differentiation from bipotent progenitors. To determine the local cis-regulatory contexts and transcription factor networks...Full Text Available

2010-08-01

265

A genome-wide study of PDZ-domain interactions in C. elegans reveals a high frequency of non-canonical binding  

UK PubMed Central (United Kingdom)

BackgroundProteins may evolve through the recruitment and modification of discrete domains, and in many cases, protein action can be dissected at the domain level. PDZ domains are...Full Text Available

266

A Web-based Interface for Communication of Data between the Clinical and Research Environments without Revealing Identifying Information  

UK PubMed Central (United Kingdom)

Recent health care policies and regulations have impacted the manner in which patient data – especially protected health information (PHI) – are handled in both the clinical...Full Text Available

2007-06-01

267

A Suppression Subtractive Hybridization Approach Reveals Niche-Specific Genes That May Be Involved in Predator Avoidance in Marine Synechococcus Isolates  

UK PubMed Central (United Kingdom)

Picocyanobacteria of the genus Synechococcus are important contributors to marine primary production and are ubiquitous in the world's oceans. This genus is genetically diverse, and...Full Text Available

2006-04-01

268

A Response Regulator That Represses Transcription of Several Virulence Operons in the Group A Streptococcus  

UK PubMed Central (United Kingdom)

A search for homologs of the Bacillus subtilis PhoP response regulator in the group A streptococcus (GAS) genome revealed three good candidates. Inactivation of one of these, recently...Full Text Available

1999-06-01

269

Survey reveals Europe's refinery-waste disposal methods, amounts, and costs  

Energy Technology Data Exchange (ETDEWEB)

Results of a survey conducted by Concawe on 75 oil refineries in Europe show that the total quantity of waste requiring disposal in 1986 was 0.5 million metric tons. This quantity of waste is but 0.13% of the total refinery throughput of 387 million metric tons during 1986. The survey revealed a wide range of disposal costs, depending on the particular properties of the waste and local conditions. A summary of total waste generation and how the waste is disposed of is shown. Details on the types of waste disposed, the disposal methods used, and the costs of disposal are detailed in this excerpt from the Concawe survey.

1989-08-28

270

Light Scalar Mesons as Manifestation of Spontaneously Broken Chiral Symmetry  

CERN Document Server

Attention is paid to the production mechanisms of light scalars that reveal their nature. We reveal the chiral shielding of the \\sigma(600) meson. We show that the kaon loop mechanism of the \\phi radiative decays, ratified by experiment, points to the four-quark nature of light scalars. We show also that the light scalars are produced in the two photon collisions via four-quark transitions in contrast to the classic P wave tensor q\\bar q mesons that are produced via two-quark transitions $\\gamma\\gamma\\to q\\bar q$. The history of spontaneous breaking of symmetry in quantum physics is discussed in Appendix.

2010-01-01

271

Genetic variability, heritability and genetic advance for seedling traits in sorghum genotypes  

International Nuclear Information System (INIS)

Analysis of data on seedling traits from 20 diverse genotypes revealed significant differences fro most of the seedling traits. Significant estimates of broad-sense heritability were observed for VI, ERI, FRTW, DRTW and R/S ratio. Genetic advance was maximum for VI,ERI and E%. The correlation of VI with ERI and R/S ratio was negative and significant, whereas it was positive and significant with E%, FSHW and DSHW. Characterization of the sorghum genotypes according to Anderson's Metro glyph Statistics revealed five different groups for seedling trails. (authors)

1999-01-01

272

Electron self-energy of high temperature superconductors as revealed by angle-resolved photoemission.  

Energy Technology Data Exchange (ETDEWEB)

In this paper, we review some of the work our group has done in the past few years to obtain the electron self-energy of high temperature superconductors by analysis of angle-resolved photoemission data. We focus on three examples which have revealed: (1) a d-wave superconducting gap, (2) a collective mode in the superconducting state, and (3) pairing correlations in the pseudogap phase. In each case, although a novel result is obtained which captures the essence of the data, the conventional physics used leads to an incomplete picture. This indicates that new physics needs to be developed to obtain a proper understanding of these materials.

1997-12-05

273

DWPF Melter No.2 Prototype Bus Bar Test Report  

Energy Technology Data Exchange (ETDEWEB)

Characterization and performance testing of a prototype DWPF Melter No.2 Dome Heater Bus Bar are described. The prototype bus bar was designed to address the design features of the existing system which may have contributed to water leaks on Melter No.1. Performance testing of the prototype revealed significant improvement over the existing design in reduction of both bus bar and heater connection maximum temperature, while characterization revealed a few minor design and manufacturing flaws in the bar. The prototype is recommended as an improvement over the existing design. Recommendations are also made in the area of quality control to ensure that critical design requirements are met.

2003-03-26

274

Comparison of temperature and humidity profiles with elastic-backscatter lidar data  

Energy Technology Data Exchange (ETDEWEB)

This contribution analyzes elastic-backscatter lidar data and temperature and humidity profiles from radiosondes acquired in Barcelona in July 1992. Elastic-backscatter lidar data reveal the distribution of aerosols within the volume of atmosphere scanned. By comparing this information with temperature and humidity profiles of the atmosphere at a similar time, we are able to asses de relationship among aerosol distribution and atmospheric stability or water content, respectively. Comparisons have shown how lidar`s revealed layers of aerosols correspond to atmospheric layers with different stability condition and water content.

1995-04-01

275

X-ray scattering signatures of {beta}-thalassemia  

Energy Technology Data Exchange (ETDEWEB)

X-ray scattering from lyophilized proteins or protein-rich samples is characterized by the presence of two characteristic broad peaks at scattering angles equivalent to momentum transfer values of 0.27 and 0.6 nm{sup -1}, respectively. These peaks arise from the interference of coherently scattered photons. Once the conformation of a protein is changed, these two peaks reflect such change with considerable sensitivity. The present work examines the possibility of characterizing the most common cause of hemolytic anaemia in Egypt and many Mediterranean countries; {beta}-thalassemia, from its X-ray scattering profile. This disease emerges from a genetic defect causing reduced rate in the synthesis of one of the globin chains that make up hemoglobin. As a result, structurally abnormal hemoglobin molecules are formed. In order to detect such molecular disorder, hemoglobin samples of {beta}-thalassemia patients are collected, lyophilized and measured using a ...

2009-08-11

276

Water uptake and exchange kinetics of polyelectrolyte films: a neutron reflectometry study  

Energy Technology Data Exchange (ETDEWEB)

The sequential layer-by-layer adsorption of polyanions and polycations to build polyelectrolyte multilayers has triggered enormous interest in their potential uses in a wide range of fields, from photonic to pharmaceutical applications. We show that the conformation of the solvent swollen films - prior to drying - is determined by the initial adsorption conditions, but can be altered ex-situ by exposure to a liquid phase of very high ionic strength. Recently it has been observed that the swelling depends on the charge of the outermost layer. In the PAH/PSS system we saw that assemblies with PSS as the outermost layer swell more than those with PAH outside. A neutron reflectivity study of this effect in addition indicated the existence of two kinds of water, bound with different strength within the films. Beside an unexpected two-step kinetics of swelling, the reflectivity curves of the layers against vacuum before and after re-hydration in D{sub 2}O vapor did not ...

2007-07-01

277

The structure of myostatin:follistatin 288: insights into receptor utilization and heparin binding  

Science.gov (United States)

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

2009-09-29

278

The reaction of hydroxylamine with bacteriorhodopsin studied with mutants that have altered photocycles: Selective reactivity of different photointermediates  

Energy Technology Data Exchange (ETDEWEB)

The reaction of the retinylidene Schiff base in bacteriorhodopsin (bR) to the water-soluble reagent hydroxylamine is enhanced by greater than 2 orders of magnitude under illumination. We have used this reaction as a probe for changes in Schiff base reactivity during the photocycle of wild-type bR and mutants defective in proton transport. We report here that under illumination at pH 6, the D85N mutant has a 20-fold lower rate and the D212N mutant has a greater than 4-fold higher rate for the light-dependent reaction with hydroxylamine compared with wild-type bR. In contrast, the reactivities of wild-type bR and the D96N and T46V mutants are similar. It has been previously shown that the D96N and T46V replacements have no significant effect on the kinetics of M formation but have dramatic effects on rate of the decay of M. We therefore conclude that the hydroxylamine reaction occurs before formation of the M intermediate. Most likely it occurs at the L stage of the cycle and reflects ...

1991-03-15

279

The influence of electromagnetic field irradiated by high-voltage transmission lines on properties of cells.  

Science.gov (United States)

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

2005-01-01

280

The effects of applied magnetic fields on the {alpha}/{gamma} phase boundary in the Fe-Si system  

Energy Technology Data Exchange (ETDEWEB)

The CALPHAD (calculations of phase diagrams) method is used to examine the effects of applied magnetic fields on the {alpha}/{gamma} phase boundary in the Fe-Si system in the paramagnetic state. The reported susceptibility data for pure Fe is first re-evaluated. The contributions to the total Gibbs energy of the ferrite ({alpha}) and austenite ({gamma}) from the external fields are calculated based on the Curie-Weiss law and the re-evaluated susceptibility data. The Fe-Si phase diagram on the Fe-rich side as a function of applied field is calculated using the Thermo-Calc(TM) package. With increasing field strength, the {gamma} loop shrinks monotonically; that is, the {alpha}/{gamma}-Fe transition temperature increases while that for {gamma}/{delta}-Fe transition decreases, albeit more slowly. Finally, in conformance with the existing CALPHAD databank, Redlich-Kister polynomials are proposed to account for the compositional and temperature dependence of the ...

2006-07-21

281

The complete mitochondrial genome of Atelura formicaria (Hexapoda: Zygentoma) and the phylogenetic relationships of basal insects.  

Science.gov (United States)

In this study, the complete sequence of the mitochondrial DNA (mtDNA) of Atelura formicaria (Hexapoda: Zygentoma) is described. The molecule is 15.205 bp in length and it is the third complete mt genome sequenced from the Zygentoma. The genome organization conforms with the putative ancestral insect gene arrangement. All protein coding genes use standard initiation codons (methionine and isoleucine). The exception is nad4 that starts with GTG, a codon used for this purpose in other insect species. A peculiar strand skew bias is observed, given that the PCGs encoded on the J-strand contain more thymines than adenines and more cytosines than guanines. This trend in nucleotide composition has been observed also in the "firebrat" Thermobia domestica (Zygentoma, Lepismatidae), but differs from that of the majority of hexapod species, including Tricholepidion gertschi (Zygentoma, Lepidotrichidae), where adenines and cytosines outnumber thymines and guanines. The presence ...

2009-03-11

282

TENT - a CORBA based component architecture for MPI-parallel CFD simulation systems and their supporting tools  

Energy Technology Data Exchange (ETDEWEB)

This paper describes TENT, a system designed for integrating the various tools and parts of a CFD simulation system (CFD - Computational Fluid Dynamics) and the simulation code itself in one interactive simulation environment. Initially the system was intended to be a TEstbed for Numerical Turbine simulation but it turned out that the approach was general enough to be suitable for more complex simulation tasks in the field of aircraft simulation. The paper will give a brief description of a CFD simulation system and its component interactions, which are the basis for describing the Component Architecture based on CORBA. This includes the control architecture using an event model and data flow considerations. Because most CFD codes use parallelization techniques based on Message Passing, a so called MIMD Object Abstraction is described in order to abstract the parallel computation threads to a single CORBA conform instance. The main goal for TENT is realizing a ...

1998-07-01

283

Study on the variations of molecular structures of some biomolecules induced by free electron laser using FTIR spectroscopy  

International Nuclear Information System (INIS)

In this study, free electron laser (FEL) with selective wavelength was used to induce structure changes of biomolecules, which were characterized by FTIR spectroscopy. For understanding of the interactions between FEL and biomolecules as well as biological tissues, the biomolecules investigated are ATP, ADP, AMP, t-RNA, D-ribose and the complex of SmCl_3-D-ribose. Their FTIR spectra before and after irradiation of FEL show molecular structure variations of the samples after irradiation of FEL, especially the rearrangement of their hydrogen bond networks. Along with the various irradiation wavelengths, irradiation time and molecular structures, the changes after irradiation are different for these molecules. In the FTIR spectra after irradiation, the phenomenon that the bands split into several peaks indicates the existence of several structures, conformations and configurations, which may be prompted by multiple photons process induced by FEL. After irradiation, ...

2007-05-01

284

Structure-retention correlations of hydrocarbons in gas-liquid and gas-solid chromatography. Cycloalkenes and cycloalkadienes  

Energy Technology Data Exchange (ETDEWEB)

The retention indices of cycloalkenes and cycloalkadienes with C/sub 6/-C/sub 13/ rings are determined by gas-liquid chromatography (GLC) on glass capillary columns coated with OV-1 and Ucon LB 550X and by gas-solid chromatrography (GSC) on a microcolumn packed with uncoated graphitized thermal carbon black (GTCB). Structure-retention correlations are derived on using index differences such as H/sup OV/, H/sup GTCB/ and ..delta..I values, considering the differences in the stereochemistry of these compounds. It is shown that the combined application of index increments obtained in GLC and GSC provides more detaled structure informations. The value of the retention index units agree with the most stable conformations of the alicyclic compounds. The high value for the energy equivalent to an index unit (..delta..G/sub I.U./ = 4.18 kJ/mol) confirms that graphitized thermal carbon black causes much stronger dispersive interactions than any nonpolar liquid phase.

1987-08-01

285

Structural analysis of experimental carbide fueled driver assmbly flow duct for testing in the FFTF  

International Nuclear Information System (INIS)

Mixed carbide fueled driver assembly experiments will be tested in FFTF fuel driver positions as part of the National Advanced Fuel Program. The design of the experiment flow ducts must assure conformance to FFTF functional requirements in addition to service as a test vehicle for the carbide fuel irradiations. Test goals of damage fluence burnup, and fluence to burnup ratio exceed those of the standard oxide fueled drivers. As a consequence, the 20% cold worked type 316 stainless steel material of construction will experience significant irradiation induced creep and swelling. Additionally, the flow duct design must withstand the enhanced thermal transients produced by the action of carbide fuel during reactor scrams. A major FFTF functional requirement is that adjacent flow ducts do not touch each other except at the load pads. This requires a realistic analysis of the creep and swelling deformation of the flow duct during an experiment lifetime. Flow duct ...

286

String Junctions and Holographic Interfaces  

CERN Document Server

In this paper we study half-BPS type IIB supergravity solutions with multiple $AdS_3\\times S^3\\times M_4$ asymptotic regions, where $M_4$ is either $T^4$ or $K_3$. These solutions were first constructed in [1] and have geometries given by the warped product of $AdS_2 \\times S^2 \\times M_4 $ over $\\Sigma$, where $\\Sigma$ is a Riemann surface. We show that the holographic boundary has the structure of a star graph, i.e. $n$ half-lines joined at a point. The attractor mechanism and the relation of the solutions to junctions of self-dual strings in six-dimensional supergravity are discussed. The solutions of [1] are constructed introducing two meromorphic and two harmonic functions defined on $\\Sigma$. We focus our analysis on solutions corresponding to junctions of three different conformal field theories and show that the conditions for having a solution charged only under Ramond-Ramond three-form fields reduce to relations involving the positions of the poles ...

2010-01-01

287

Spectroscopic studies on the interaction of the antibiotic lasalocid A (x-537a) with technetium (V) ions in methanol  

International Nuclear Information System (INIS)

In the present study, the authors examine the interactions of pentavalent technetium ions (TcO/sup 3+/) with the basic form of the lasalocid A in pure methanol solvent and in methanol-water mixtures. There are a number of reasons for such a study. First, the interactions of technetium ions with biologically important compounds are of considerable importance owing to the widespread use of /sup 99m/Tc in diagnostic radio-imaging. Second, lasalocid A is known to transport metal ions across phospholipid bilayer membranes and between the aqueous cores of phospholipid inverse micelles. Third, lasalocid A is known to bind and solubilize metal ions in bulk organic liquid phases. Fourth, the conformation adopted by lasalocid A on interaction with TcO/sup 3+/ appears to be different than those found in most other cases and circumstances. Fifth, it may also be possible to use the competition of TcO/sup 3+/ with other, physiologically relevant cations (Na/sup +/, K/sup +/, ...

288

Silica Polyamine Composites: New Supramolecular Materials for Cation and Anion Recovery and Remediation  

Energy Technology Data Exchange (ETDEWEB)

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

2006-03-01

289

Short-term regulation of muscarinic acetylcholine receptors: An assessment utilizing mouse brain and mouse neuroblastoma cells  

Energy Technology Data Exchange (ETDEWEB)

The effects of muscarinic agonists and diisopropylfluorophosphate (DFP) on muscarinic receptor density and muscarinic receptor-mediated responses was assessed in mouse brain and mouse neuroblastoma cells (clone N1E-115). Utilizing the antagonist ({sup 3}H)quinuclidinyl benzilate (({sup 3}H)QNB), there was no difference in the maximal binding capacity (B{sub max}) or equilibrium dissociation constant (K{sub d}) between untreated and 24 hour DFP-treated mice. However, one administration of DFP produced a 24% and 33% decrease in B{sub max} measured by ({sup 3}H)N-methylscopolamine (({sup 3}H)NMS) after 18 and 24 hours which was rapidly reversible within 36 hours after DFP treatment. The loss of ({sup 3}H)NMS binding sites following acute DFP treatment was not accompanied by a change in a particular muscarinic receptor binding conformation. Furthermore, the magnitude of muscarinic receptor-mediated phosphoinositide hydrolysis was unchanged following short-term DFP ...

1988-01-01

290

Predicting Knot and Catenane Type of Products of Site-specific Recombination on Twist Knot Substrates  

CERN Document Server

Site-specific recombination is an important cellular process that yields a variety of knotted and catenated DNA products on supercoiled circular DNA. Twist knots are some of the most common conformations of these products. They are also one of the simplest families of knots and catenanes. Yet, our systematic understanding of their implication in DNA and important cellular processes like site-specific recombination is very limited. Here we present a topological model of site-specific recombination characterising all possible products of site-specific recombination on twist knot substrates, extending previous work of Buck and Flapan. We illustrate how to use our model to examine previously uncharacterized experimental data. We show how our model can help determine the sequence of products in multiple rounds of processive recombination and distinguish between products of processive and distributive recombination. Companion paper (arXiv:1007.2115v1 math.GT) provides ...

2010-01-01

291

Precise characterisation of nanochannels in track etched membranes by SAXS and SANS  

Energy Technology Data Exchange (ETDEWEB)

Poster session: Abstract is full text. Track membranes are thin polymer foils irradiated by heavy ions. The defects created by the heavy ions are located along the ions trajectory, the track. It is possible to open channels by etching with a chemical agent. These channels are very uniform. Small Angle Scattering (of X rays and neutrons) give global information about the characteristics of the channel shape. As the nanochannels are strictly parallel, an excellent sample orientation is required to obtain interpretable spectra. Then shoulders due to the oscillations of the Bessel function (radial part of the channel shape Fourier transform) are easily seen in the scattered intensity in the PXY data treatment software of SAS spectra allow to determine the channel diameter with its dispersion law, to demonstrate the existence of a wall thickness with a linearly varying density, and to assess the roughness. PXY can also detect non cylindric shapes like single or double cones or spindles. ...

2003-05-01

292

Photovoltaic industry manufacturing technology. Final report  

Energy Technology Data Exchange (ETDEWEB)

This report contains the results of the Photovoltaic (PV) Industry Manufacturing Technology Assessment performed by the Automation and Robotics Research Institute (ARRI) of the University of Texas at Arlington for the National Renewable Energy laboratory. ARRI surveyed eleven companies to determine their state-of-manufacturing in the areas of engineering design, operations management, manufacturing technology, equipment maintenance, quality management, and plant conditions. Interviews with company personnel and plant tours at each of the facilities were conducted and the information compiled. The report is divided into two main segments. The first part of the report presents how the industry as a whole conforms to ``World Class`` manufacturing practices. Conclusions are drawn from the results of a survey as to the areas that the PV industry can improve on to become more competitive in the industry and World Class. Appendix A contains the questions asked in the ...

1998-08-01

293

Office of Inspector General audit report on the U.S. Department of Energy`s consolidated financial statements for fiscal year 1998  

Energy Technology Data Exchange (ETDEWEB)

The Department prepared the Fiscal Year 1998 Accountability Report to combine critical financial and program performance information in a single report. The Department`s consolidated financial statements and the related audit reports are included as major components of the Accountability Report. The Office of Inspector General audited the Department`s consolidated financial statements as of and for the years ended September 30, 1998 and 1997. In the opinion of the Office of Inspector General, except for the environmental liabilities lines items in Fiscal year 1998, these financial statements present fairly, in all material respects, the financial position of the Department as of September 30, 1998 and 1997, and its consolidated net cost, changes in net position, budgetary resources, financing activities, and custodial activities for the years then ended in conformity with Federal accounting standards. In accordance with Government Auditing Standards, the Office of ...

1999-02-01

294

Off-road compression-ignition engine emission regulations under the Canadian Environmental Protection Act 1999 : guidance document  

Energy Technology Data Exchange (ETDEWEB)

This guide explained the requirements for Off-Road Compression Ignition Engine Emission Regulations established under the Canadian Environmental Protection Act. The regulations are enforced by Environment Canada, which authorizes and monitors the use of the national emissions mark. The regulations prescribe standards for off-road engines that operate as reciprocating, internal combustion engines, other than those that operate under characteristics similar to the Otto combustion cycle and that use a spark plug or other sparking device. The regulations apply to engines that are typically diesel-fuelled and found in construction, mining, farming and forestry machines such as tractors, excavators and log skidders. Four different types of persons are potentially affected by the regulations: Canadian engine manufacturers; distributors of Canadian engines or machines containing Canadian engines; importers of engines or machines for the purpose of sale; and persons not in companies importing ...

2006-03-15

295

Off-road compression-ignition engine emission regulations under the Canadian Environmental Protection Act 1999 : guidance document  

International Nuclear Information System (INIS)

This guide explained the requirements for Off-Road Compression Ignition Engine Emission Regulations established under the Canadian Environmental Protection Act. The regulations are enforced by Environment Canada, which authorizes and monitors the use of the national emissions mark. The regulations prescribe standards for off-road engines that operate as reciprocating, internal combustion engines, other than those that operate under characteristics similar to the Otto combustion cycle and that use a spark plug or other sparking device. The regulations apply to engines that are typically diesel-fuelled and found in construction, mining, farming and forestry machines such as tractors, excavators and log skidders. Four different types of persons are potentially affected by the regulations: Canadian engine manufacturers; distributors of Canadian engines or machines containing Canadian engines; importers of engines or machines for the purpose of sale; and persons not in companies importing ...

1999-01-01

296

Observability of complex ghosts and tachyons  

International Nuclear Information System (INIS)

The complex ghost introduced previously by the present author is studied from a standpoint whether its effects are observable by experiments or not. According to the theory of complex ghost the scattering cross section of two real particles shows some particular properties. It has a kind of resonance peak at a certain energy which does not conform to the Breit-Wigner formula. It has also a peak for a certain energy transfer, if there exist tachyons. The tachyon is a kind of ghost and is allowed to exist in the theory. Using these properties the complex ghosts are expected to be detected by experiments. The recently observed resonance psi(3.1) is supposed to be the complex ghost of photon, since they have the same quantum numbers. If it is assumed, some properties of the resonance known by experiments are explained naturally to a certain extent. Along the same line it is not unnatural to expect that the photon is also accompanied by a tachyon as a ghost. An ...

297

NMR studies of Borrelia burgdorferi OspA, a 28 kDa protein containing a single-layer #beta#-sheet  

International Nuclear Information System (INIS)

The crystal structure of outer surface protein A (OspA) from Borrelia burgdorferi contains a single-layer #beta#-sheet connecting the N- and C-terminal globular domains. The central #beta#-sheet consists largely of polar amino acids and it is solvent-exposed on both faces, which so far appears to be unique among known protein structures. We have accomplished nearly complete backbone H, C and N and C";/H"#beta# assignments of OspA (28 kDa) using standard triple resonance techniques without perdeuteration. This was made possible by recording spectra at a high temperature (45 "oC ). The chemical shift index and "1"5N T_1/T_2 ratios show that both the secondary structure and the global conformation of OspA in solution are similar to the crystal structure, suggesting that the unique central #beta#-sheet is fairly rigid.

1998-05-01

298

Microlocal analysis of asymptotically hyperbolic and Kerr-de Sitter spaces  

CERN Document Server

In this paper we develop a general, systematic, microlocal framework for the Fredholm analysis of non-elliptic problems, including high energy (or semiclassical) estimates, which is stable under perturbations. This framework is relatively simple given modern microlocal analysis, and only takes a bit over a dozen pages after the statement of notation. It resides on a compact manifold without boundary, hence in the standard setting of microlocal analysis, including semiclassical analysis. The rest of the paper is devoted to applications. Many natural applications arise in the setting of non-Riemannian b-metrics in the context of Melrose's b-structures. These include asymptotically Minkowski metrics, asymptotically de Sitter-type metrics on a blow-up of the natural compactification and Kerr-de Sitter-type metrics. The simplest application, however, is to provide a new approach to analysis on Riemannian or Lorentzian (or indeed, possibly of other signature) conformally ...

2010-01-01

299

Maintenance implementation plan for the B Plant/WESF. Revision 4  

Energy Technology Data Exchange (ETDEWEB)

This Maintenance Implementation Plan (MIP) has been developed for maintenance functions associated with the B Plant/WESF (Waste Encapsulation Storage Facility) complex. The objective of this plan is to provide baseline information for establishing and identifying WHC conformance programs and policies applicable to implementation of DOE order 4330.4B guidelines. In addition, this maintenance plan identifies the actions necessary to develop a cost-effective and efficient maintenance program at B Plant/WESF. The B Plant WESF facility complex consists of three main facilities and several support structures located in the 200 East Area of the Hanford site. B Plant is a transition facility that is required to ensure safe storage and management of WESF (operating facility) cesium and strontium capsules. B Plant/WESF also contains substantial radiological inventory from previous campaigns. There are no production activities at B Plant, but several of its operating systems ...

1996-01-01

300

Localized tachyons in C{sup 3}/Z{sub N}  

Energy Technology Data Exchange (ETDEWEB)

We study the condensation of localized closed string tachyons in C{sup 3}/Z{sub N} non-supersymmetric noncompact orbifold singularities via renormalization group flows that preserve supersymmetry in the worldsheet conformal field theory and their interrelations with the toric geometry of these orbifolds. We show that for worldsheet supersymmetric tachyons, the endpoint of tachyon condensation generically includes 'geometric' terminal singularities (orbifolds that do not have any marginal or relevant Kahler blowup modes) as well as singularities in co-dimension two. Some of the various possible distinct geometric resolutions are related by flip transitions. For Type II theories, we show that the residual singularities that arise under tachyon condensation in various classes of Type II theories also admit a Type II GSO projection. We further show that Type II orbifolds entirely devoid of marginal or relevant blowup modes (Kahler or otherwise) cannot ...

2004-08-01

301

Limiting values of radionuclide intake and air concentration and dose conversion factors for inhalation, submersion, and ingestion: Federal guidance report No. 11  

Energy Technology Data Exchange (ETDEWEB)

Radiation protection programs for workers are based, in the United States, on a hierarchy of limitations stemming from Federal guidance approved by the President. This guidance, which consists of principles, policies, and numerical primary guides, is used by Federal agencies as the basis for developing and implementing their own regulatory standards. The primary guides are usually expressed in terms of limiting doses to workers. The protection of workers against taking radioactive materials into the body, however, is accomplished largely through the use of regulations based on derived guides expressed in terms of quantities or concentrations of radionuclides. The values of these derived guides are chosen so as to assure that workers in work environments that conform to them are unlikely to receive radiation doses that exceed the primary guides. The purpose of the present report is to set forth derived guides that are consistent with current Federal radiation ...

1988-09-01

302

Kinetics of complexing activation by the magnesium ion on green crab (Scylla serrata) alkaline phosphatase.  

Science.gov (United States)

As with mammalian enzymes, green crab (Scylla serrata) alkaline phosphatase can be activated by Mg2+ through a time-dependent course. The activation is mainly a Vmax effect. Tsou's method was used to study the kinetic course of activation. The results show that the enzyme was activated by a complexing scheme that had not been previously identified: the enzyme first reversibly and quickly binds Mg2+ and then undergoes a slow reversible course to activation, with a relatively high activation energy (78 +/- 4 kJ/mol) and a slow conformational change. The activation reaction is a single molecule reaction, and the apparent activation rate constant is independent of Mg2+ concentration if the concentration is sufficiently high. The microscopic rate constants of activation and the association constant were determined from the measurements. The proposed scheme may also be applied to the Mg2+ activation mechanism for mammalian enzyme, to explain why the activation rate is ...

2001-01-01

303

KINEMATICS AT THE EDGE OF THE GALACTIC BULGE: EVIDENCE FOR CYLINDRICAL ROTATION  

International Nuclear Information System (INIS)

We present new results from BRAVA, a large-scale radial velocity survey of the Galactic bulge, using M giant stars selected from the Two Micron All Sky Survey catalog as targets for the Cerro Tololo Inter-American Observatory 4 m Hydra multi-object spectrograph. The purpose of this survey is to construct a new generation of self-consistent bar models that conform to these observations. We report the dynamics for fields at the edge of the Galactic bulge at latitudes b = -8 deg. and compare to the dynamics at b = -4 deg. We find that the rotation curve V(r) is the same at b = -8 deg. as at b = -4 deg. That is, the Galactic boxy bulge rotates cylindrically, as do boxy bulges of other galaxies. The summed line-of-sight velocity distribution at b = -8 deg. is Gaussian, and the binned longitude-velocity plot shows no evidence for either a (disk) population with cold dynamics or for a (classical bulge) population with hot dynamics. The observed kinematics are well modeled ...

2009-09-10

304

Interaction of bovine serum albumin with some novel PEG-containing diblock copolymers  

British Library Electronic Table of Contents (United Kingdom)

A comparative study on the interaction of different PEG-containing diblock copolymers including SA400, SA600, SA1500 and OA1500 (stearyl and oleyl esters of polyethylene glycol with 400, 600 and 1500 molecular weights, respectively) with bovine serum albumin (BSA) was carried out using isothermal titration calorimetry (ITC), attenuated total reflectance Fourier transform infrared (ATR-FTIR), circular dichroism (CD), and fluorescence spectroscopies. ITC data show that SA400, SA600, SA1500 and OA1500 bind to BSA, with association constants of (14.5, 3.16, 50.7 and 17.6)x103M-1, respectively. Results also show that the binding is enthalpically driven, disfavored by conformational entropy. Quantitative analysis of the FTIR absorbance spectra at amide Iprime (1600-1700cm-1) as well as far UV ci...

2008-01-01

305

Intensity-Modulated Radiation Therapy with Noncoplanar Beams for Treatment of Prostate Cancer in Patients with Bilateral Hip Prosthesis-A Case Study  

International Nuclear Information System (INIS)

Megavoltage photon intensity-modulated radiation therapy (IMRT) is typically used in the treatment of prostate cancer at our institution. Approximately 1% to 2% of patients with prostate cancer have hip prostheses. The presence of the prosthesis usually complicates the planning process because of dose perturbation around the prosthesis, radiation attenuation through the prosthesis, and the introduction of computed tomography artifacts in the planning volume. In addition, hip prostheses are typically made of materials of high atomic number, which add uncertainty to the dosimetry of the prostate and critical organs in the planning volume. When the prosthesis is bilateral, treatment planning is further complicated because only a limited number of beam angles can be used to avoid the prostheses. In this case study, we will report the observed advantages of using noncoplanar beams in the delivery of IMRT to a prostate cancer patient with bilateral hip prostheses. The treatment was planned ...

2010-01-01

306

Highly specific antiserum for arginine vasopressin  

International Nuclear Information System (INIS)

A high sensitivity (titer 60-150,000) radioimmunoassay for arginine vasopressin (AVP) has been developed using synthetic AVP as antigen and standard. The specificity of the antiserum has been characterized in detail by measuring the relative binding affinities of 29 analogs and fragments of AVP. In general, single amino acid substitution or deletion in the AVP molecule caused a reduction in binding to the antiserum; binding was further impaired for analogs which had multiple substitutions. ''Ring'' and ''tail'' fragments of the neurohypophysial hormones did not bind to the antiserum, and the only analog which the antiserum could not differentiate from AVP was deamino-AVP. More specifically, the antiserum exhibited the following properties: position 1, no requirement for a position charge at "1/_2 Cys; positions 2 and 3, requirements for #pi#-#pi# interacting pair of aromatic side chains and for Tyr at position 2; position 4, requirement for Gln (>Thr > Val); position 8, ...

307

Groundwater surveillance plan for the Oak Ridge Reservation  

Energy Technology Data Exchange (ETDEWEB)

US Department of Energy (DOE) Order 5400.1 requires the preparation of environmental monitoring plans and implementation of environmental monitoring programs for all DOE facilities. The order identifies two distinct components of environmental monitoring, namely effluent monitoring and environmental surveillance. In general, effluent monitoring has the objectives of characterizing contaminants and demonstrating compliance with applicable standards and permit requirements, whereas environmental surveillance has the broader objective of monitoring the effects of DOE activities on on- and off-site environmental and natural resources. The purpose of this document is to support the Environmental Monitoring Plan for the Oak Ridge Reservation (ORR) by describing the groundwater component of the environmental surveillance program for the DOE facilities on the ORR. The distinctions between groundwater effluent monitoring and groundwater surveillance have been defined in the Martin Marietta ...

1994-07-01

308

First detection of lamella-gyroid-cylinder phase transition of neat polyethylene-poly(ethylene oxide) diblock copolymers on the basis of synchrotron WAXD/SAXS and infrared/Raman spectral measurements  

International Nuclear Information System (INIS)

The phase transition behaviour of polyethylene-b-poly(ethylene oxide) (PE-b-PEO) diblock copolymer with relatively short chain lengths has been studied on the basis of temperature dependent infrared and Raman spectral measurements and synchrotron WAXD/SAXS simultaneous measurements, from which the concrete structural changes were deduced successfully from the various levels of molecular chain conformation, chain packing mode and higher-order structure. The higher-order structure has been found to transform between lamella, perforated lamella, gyroid, cylinder and sphere structures. The inner structural changes occurring in the polyethylene and poly(ethylene oxide) parts have been related with these morphological changes. The morphological transition from lamella to gyroid occurs with keeping the crystalline state of polyethylene parts. This apparently curious transition can be interpreted reasonably by assuming the thermally-activated chain motion in the crystal ...

2009-08-01

309

Experimental determination of the dosimetric characteristics for the I-Plant"T"M model 3600 "1"2"5I brachytherapy source  

International Nuclear Information System (INIS)

The dosimetric characteristics for a new brachytherapy seed source (I-Plant"T"M model 3600) were measured using LiF thermoluminescent dosimeters and appropriate phantom materials in conformance with the methodology and guidance provided by the AAPM Task Group 43. The I-Plant"T"M model 3600 is the successor to the I-Plant"T"M model 3500. The major difference between these sources is that the model 3600 contains a leaded-glass core to provide radio-opacity (while the model 3500 contains a silver core), which does not produce spectral contamination upon neutron activation. The dose rate constant #LAMBDA# for the model 3600 was determined to be 1.00 Gy h"-"1 U"-"1 (with a 6% overall relative standard deviation), compared to 1.01 cGy h"-"1 U"-"1 reported for the model 3500 in previous studies. The remaining dosimetric characteristics also are similar for both sources.

2005-06-01

310

Elephant's foot phenomenon in liquid storage tanks  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a method for analyzing the seismic response of a flat bottomed cylindrical liquid storage tank to vertical earthquake excitation. Here, vertical earthquake acceleration is considered to correspond to an increase in the density of a stored liquid. Taking into account the vertical and horizontal earthquake loads, hydrostatic pressure, and considering restrictive moment and shear forces at shell-bottom welded joint, the author has calculated circumferential and longitudinal stresses. These are combined to more accurately approximate the stresses at the base shell course. The calculated result closely conforms to the actual damage, termed ''elephant's foot,'' observed in the fuel storage tanks damaged in the Tangshan earthquake. This result shows that the ''elephant's foot'' phenomenon is not caused by buckling of the tank shell due to longitudinal compressive ...

1983-01-01

311

Diffractive deep inelastic scattering in an AdS/CFT inspired model: A phenomenological study  

International Nuclear Information System (INIS)

The analytical treatment of the nonperturbative QCD dynamics is one of the main open questions of the strong interactions. Currently, it is only possible to get some qualitative information about this regime considering other QCD-like theories, as, for example, the N=4 super Yang-Mills theory, where one can perform calculations in the nonperturbative limit of large 't Hooft coupling using the anti-de Sitter space/conformal field theory (AdS/CFT). Recently, the high energy scattering amplitude was calculated in the AdS/CFT approach, applied to deep-inelastic scattering and confronted with the F_2 HERA data. In this work we extend the nonperturbative AdS/CFT inspired model for diffractive processes and compare its predictions with a perturbative approach based on the Balitsky-Kovchegov equation. We demonstrate that the AdS/CFT inspired model is not able to describe the current F_2"D"("3") HERA data and predicts a similar behavior to that from the Balitsky-Kovchegov ...

2010-05-01

312

Development status of a small, direct-injection diesel engine at Isuzu  

Energy Technology Data Exchange (ETDEWEB)

Development status of small direct injection diesel engine at Isuzu Motors Ltd. is reviewed. There is much difficulty in combustion optimization of small DI engines, due to small combustion chamber volume, large surface to volume ratio, wide engine speed range and so on. Novel ideas in the area of injection system, combustion chamber and induction swirl were tried to solve these problems and their effects are presented here. Our prototype DI engines which adopted some of these ideas has turned out to have better fuel economy by about 15 percent, 2 - 3 dB(A) higher noise level than IDI and almost the same power output performance as IDI. As to exhaust emissions, they have a possibility to conform to '86 California emission standards, in inertia weight classes up to 2625 LBS. The remaining problem areas are noise emission, durability of injection pump and cabin heater performance. These problems must be solved by further innovation, before DI engines will be ...

1985-01-01

313

Densification of ashes from a thermal power plant  

Energy Technology Data Exchange (ETDEWEB)

Power plants generate a great amount of ash during coal combustion. From this process two different kinds of ashes are extracted: fly ash (FA) and bottom ash (BA). In this work possible use of both fly and bottom ash as raw material for the ceramic industry is analyzed. The samples were formed by mechanical mixing of both kinds of ashes, and density evolution during conformation as structural ceramic (packing, pressing and sintering) was studied. It was verified that powders with larger fly ash content exhibited higher packing density resulting in compacts with improved green and sintered densities. Preheating treatments at temperatures above 600{sup o}C also increased the green and sintered densities. Dilatometric curves on compacts formed from FA and BA powders were run at constant heating rate and at isothermal cycles. From the analysis of these data it can be established that liquid-phase sintering is the densification mechanism present at 1180{sup o}C.

2003-07-01

314

Crystalline and Liquid Crystalline Organic-Inorganic Hybrid Salts with Cation-Sensitized Hexanuclear Molybdenum Cluster Complex Anion Luminescence  

British Library Electronic Table of Contents (United Kingdom)

Abstract The salts [Cnmim]2[Mo6Cl14] (mim = methylimidazolium; n = 4, 6, 12, 16, 18) have been obtained by reaction of CnmimCl with MoCl2. Thermal analysis shows the melting point decreases with increasing alkyl chain length of the cation. The imidazolium chloromolybdates(II) with n = 6-18 decompose above 340 C; [C18mim]2[Mo6Cl14] is thermally stable up to 390 C. All compounds are insensititve to the constituents of the atmosphere. Of the higher melting salts [Cnmim]2[Mo6Cl14] (n = 4, 6), high-quality single crystals could be obtained. Single-crystal X-ray structural analyses clearly show that the cluster complex anion [Mo6Cl14]2- has an electron-precise octahedral {Mo6} cluster. For [C4mim]2[Mo6Cl14], two polymorphs differing in the cation alkyl-side-chain conformation were obtained. The ...

2011-01-01

315

Correlation of Byrd and Selborne groups, with implications for the Byrd Glacier discontinuity, central Transantarctic Mountains, Antarctica  

International Nuclear Information System (INIS)

South of Byrd Glacier, central Transantarctic Mountains, Antarctica, Lower Cambrian Shackleton Limestone (Byrd Group) is divided into four informal members. The transition from Shackleton carbonates to clastics of Starshot Formation is conformable, with alternating units of limestone and argillite, and a thick succession of pillow basalt. Douglas Conglomerate is interbedded with and overlies Starshot Formation, and overlies folded Shackleton Limestone unconformably. Lower amphibolite-grade Selborne Group is composed of Madison Marble and Contortion Schist. The contact between the two formations is interbedded marble and schist, and includes metabasalt. We correlate Byrd Group with Selborne Group, Shackleton Limestone with Madison Marble, and Starshot Formation and Douglas Conglomerate with Contortion Schist. These correlations and the lack of equivalent lithologies to the north of Byrd Glacier imply that Byrd Glacier is the northern boundary of the Byrd ...

2004-06-01

316

Consequences of warm-up of a sector above 80K  

CERN Document Server

There may be circumstances when a sector has to be partially or totally warmed-up to temperatures above 80 K, that is when thermal dilatation starts to play a role. Some equipment have been identify as presenting a risk, like the non-conform "plug-in" modules in the arcs. Because of motion induced by thermal dilatation, the electrical (ElQA) quality control may also have to be done again after cool-down. The main reason identified so far for partial warm-up is the required maintenance of the cooling towers and the cryogenics plants. There is also the request from the vacuum group to periodically warm-up the beam screen to temperatures in the 100 K region to release and pump-out the gas crysorbed on the surface of the beam screen. Observed and expected temperature conditions and statistics on failures of PIMs in sectors which have been warmed-up will be presented in this contribution. Methods to detect buckled PIMs will be described, as well as a recommended ...

2009-01-01

317

Conceptual study on advanced PWR system  

Energy Technology Data Exchange (ETDEWEB)

In this study, the adoptable essential technologies and reference design concept of the advanced reactor were developed and related basic experiments were performed. (1) Once-through Helical Steam Generator: a performance analysis computer code for heli-coiled steam generator was developed for thermal sizing of steam generator and determination of thermal-hydraulic parameters. (2) Self-pressurizing pressurizer : a performance analysis computer code for cold pressurizer was developed. (3) Control rod drive mechanism for fine control : type and function were surveyed. (4) CHF in passive PWR condition : development of the prediction model bundle CHF by introducing the correction factor from the data base. (5) Passive cooling concepts for concrete containment systems: development of the PCCS heat transfer coefficient. (6) Steam injector concepts: analysis and experiment were conducted. (7) Fluidic diode concepts : analysis and experiment were conducted. (8) Wet thermal insulator : tests ...

1997-07-01

318

Comparison of newer synthetic and biological wound dressings.  

Science.gov (United States)

In 18 piglets, weighing 10-15 kg, third-degree burns or full-thickness skin excisions of 4 X 4 cm were inflicted. The effect of five dressing materials on adhesiveness to the wounds, appearance, conformability, wound contraction, bacterial count, and morphology of the wound was studied at the end of the seventh and fourteenth days without dressing changes. In 11 piglets with a burn wound, the most adherent dressing was collagen sponge(CS), followed by polyurethane sponge (PU), pigskin xenograph (PS), and xeroform. CS more effectively debrided the wound from coagulated necrotic tissue than the other dressings. Wound contraction was maximal with CS dressing (52%), followed by PU (44%), xeroform (32%), and PS (27%). In another seven piglets with full-thickness excised wounds, a velour dressing made of polytetrafluoroethylene (PTFE) or PU adhered significantly more than CS or PS. Wound contraction was greater with CS (37%) or PTFE (35%) than with PS (23%) or PU (18%). ...

1981-06-01

319

Circuit breaker lockout device  

Energy Technology Data Exchange (ETDEWEB)

An improved lockout assembly for locking a circuit breaker in a selected off or on position is provided. The lockout assembly includes a lock block and a lock pin. The lock block has a hollow interior which fits over the free end of a switch handle of the circuit breaker. The lock block includes at least one hole that is placed in registration with a hole in the free end of the switch handle. A lock tab on the lock block serves to align and register the respective holes on the lock block and switch handle. A lock pin is inserted through the registered holes and serves to connect the lock block to the switch handle. Once the lock block and the switch handle are connected, the position of the switch handle is prevented from being changed by the lock tab bumping up against a stationary housing portion of the circuit breaker. When the lock pin installed, an apertured-end portion of the lock pin is in registration with another hole on the lock block. Then a special scissors ...

1992-01-01

320

Biophysical analysis of DNA modified by 1,2-diaminocyclohexane platinum(II) complexes  

Energy Technology Data Exchange (ETDEWEB)

Modification of DNA and double-stranded deoxyoligonucleotides with antitumor 1,2-diamino-cyclohexanedinitroplatinum(II) (Pt-dach) complexes was investigated with the aid of physico-chemical methods and chemical probes of nucleic acid conformation. The three Pt-dach complexes were used which differed in isomeric forms of the dach non-leaving ligand-Pt(1R,2R-dach), Pt(1S,2S-dach) and Pt(1R,2S-dach) complexes. The latter complex has lower antitumor activity than the other two Pt-dach complexes. Pt(1R,2S-dach) complex exhibits the slowest kinetics of its binding to DNA and of the conversion of monofunctional binding to bifunctional lesions. The anomalously slow electrophoretic mobility of multimers of the platinated and ligated oligomers suggests that bifunctional binding of Pt-dach complexes to a d(GG) site within double-stranded oligonucleotides induces bending of the oligomer. It is proposed that different effects of the Pt-dach complexes on DNA observed in this ...

1992-01-25

321

Atomic force microscopy and surface-enhanced Raman scattering detection of DNA based on DNA-nanoparticle complexes  

Energy Technology Data Exchange (ETDEWEB)

We report a simple method for the label-free detection of double-stranded DNA using surface-enhanced Raman scattering (SERS). We prepared cetyltrimethylammonium bromide (CTAB)-capped silver nanoparticles and a DNA-nanoparticle complex by adding silver nanoparticles to {lambda}-DNA solutions. In the present study, the utilization of CTAB-capped silver nanoparticles facilitates the electrostatic interaction between DNA molecules and silver nanoparticles; at the same time, the introduction of DNA avoids adding aggregating agent for the formation of nanoparticle aggregates to obtain large enhancement of DNA, because the DNA acts as both the probe molecules and aggregating agent of Ag nanoparticles. Atomic force microscopy (AFM) studies show that the morphology of DNA-Ag nanoparticle complexes seems to be determined by the concentrations of the DNA and the nanoparticles. Surface-enhanced Raman scattering (SERS) studies show that the morphology of the complexes plays a significant role in ...

2009-03-25

322

All-atom molecular dynamics simulations using orientational constraints from anisotropic NMR samples  

Science.gov (United States)

Orientational constraints obtained from solid state NMR experiments on anisotropic samples are used here in molecular dynamics (MD) simulations for determining the structure and dynamics of several different membrane-bound molecules. The new MD technique is based on the inclusion of orientation dependent pseudo-forces in the COSMOS-NMR force field. These forces drive molecular rotations and re-orientations in the simulation, such that the motional time-averages of the tensorial NMR properties approach the experimentally measured parameters. The orientational-constraint-driven MD simulations are universally applicable to all NMR interaction tensors, such as chemical shifts, dipolar couplings and quadrupolar interactions. The strategy does not depend on the initial choice of coordinates, and is in principle suitable for any flexible molecule. To test the method on three systems of increasing complexity, we used as constraints some deuterium quadrupolar couplings from the literature on ...

2007-03-03

323

All-atom molecular dynamics simulations using orientational constraints from anisotropic NMR samples  

Energy Technology Data Exchange (ETDEWEB)

Orientational constraints obtained from solid state NMR experiments on anisotropic samples are used here in molecular dynamics (MD) simulations for determining the structure and dynamics of several different membrane-bound molecules. The new MD technique is based on the inclusion of orientation dependent pseudo-forces in the COSMOS-NMR force field. These forces drive molecular rotations and re-orientations in the simulation, such that the motional time-averages of the tensorial NMR properties approach the experimentally measured parameters. The orientational-constraint-driven MD simulations are universally applicable to all NMR interaction tensors, such as chemical shifts, dipolar couplings and quadrupolar interactions. The strategy does not depend on the initial choice of coordinates, and is in principle suitable for any flexible molecule. To test the method on three systems of increasing complexity, we used as constraints some deuterium quadrupolar couplings from the literature on ...

2007-05-15

324

All-atom molecular dynamics simulations using orientational constraints from anisotropic NMR samples  

International Nuclear Information System (INIS)

Orientational constraints obtained from solid state NMR experiments on anisotropic samples are used here in molecular dynamics (MD) simulations for determining the structure and dynamics of several different membrane-bound molecules. The new MD technique is based on the inclusion of orientation dependent pseudo-forces in the COSMOS-NMR force field. These forces drive molecular rotations and re-orientations in the simulation, such that the motional time-averages of the tensorial NMR properties approach the experimentally measured parameters. The orientational-constraint-driven MD simulations are universally applicable to all NMR interaction tensors, such as chemical shifts, dipolar couplings and quadrupolar interactions. The strategy does not depend on the initial choice of coordinates, and is in principle suitable for any flexible molecule. To test the method on three systems of increasing complexity, we used as constraints some deuterium quadrupolar couplings from the literature on ...

2007-05-01

325

Accelerated aging tests of liners for uranium mill tailings disposal  

Energy Technology Data Exchange (ETDEWEB)

This document describes the results of accelerated aging tests to determine the long-term effectiveness of selected impoundment liner materials in a uranium mill tailings environment. The study was sponsored by the US Department of Energy under the Uranium Mill Tailings Remedial Action Project. The study was designed to evaluate the need for, and the performance of, several candidate liners for isolating mill tailings leachate in conformance with proposed Environmental Protection Agency and Nuclear Regulatory Commission requirements. The liners were subjected to conditions known to accelerate the degradation mechanisms of the various liners. Also, a test environment was maintained that modeled the expected conditions at a mill tailings impoundment, including ground subsidence and the weight loading of tailings on the liners. A comparison of installation costs was also performed for the candidate liners. The laboratory testing and cost information prompted the ...

1981-11-01

326

222-S Laboratory maintenance implementation plan  

Energy Technology Data Exchange (ETDEWEB)

This Maintenance Improvement Plan has been developed for maintenance functions associated with the 222-S Laboratory. This plan is developed from the guidelines presented by Department of Energy (DOE) Order 4330.4B, Maintenance Management Program (DOE 1994), Chapter 11. The objective of this plan is to provide information for establishing and identifying WMH conformance programs and policies applicable to implementation of DOE Order 4330.4B guidelines. In addition, this maintenance plan identifies the actions necessary to develop a cost effective and efficient maintenance program at 222-S Laboratory. Maintenance activities are mainly going to be performed by existing maintenance organizations within Waste Management Federal Services of Hanford (WMH). Most maintenance performed at 222-S Laboratory is performed by the 222-S Laboratory maintenance organization. This 222-S Laboratory Maintenance Implementation Plan provides the interface requirements and ...

1997-08-13

327

Treatment of prostatic cancer using daily intermittent multiportal therapy (DIMT) technique  

Energy Technology Data Exchange (ETDEWEB)

In the treatment of prostatic cancer using a newly proposed intermittent multiportal therapy (DIMT), acute reactions, change in tumor marker levels, and complications more than 6 months after treatment were evaluated. From June 1989 to September 1990, 26 patients with prostatic cancer (stage A2, 3 patients; B, 9; C, 2; D, 10; recurrence, 2) were treated. Fifteen patients were followed up for more than one year, with a mean period of 11.6 months. The treatment schedule is 52.5 Gy in 16 fractions in 4 weeks for radical treatment, and 30.0 Gy in 8 fractions in 2 weeks for palliative treatment. The 360 degree rotation about the patient was divided into 16 fractions, and 2 opposing fractions were used in one day as parallel opposed portals to treat the target volume. The fractions were serially treated one per day, so that 8 treatment days produced a total dose of distribution similar to that for conventional conformational therapy. The size of the irradiation field ...

1992-06-01

328

Solution conformations of CaCl sub 2 and Ca(NO sub 3 ) sub 2 complexes of chiral tetramethyl 18-crown-6 macrocycles: A 1D and 2D sup 1 H and sup 13 C NMR investigation  

Energy Technology Data Exchange (ETDEWEB)

One- and two-dimensional NMR techniques have been used to investigate the solution structures of (2S,6S,11S,15S)-2,6,11,15-tetramethyl-1,4,7,10,13,16-hexaoxacyclooctadecane (I) and (2R,3R,11R,12R)-2,3,11,12-tetramethyl-1,4,7,10,13,16-hexaoxyacyclooctadecane (II) macrocycle complexes of CaCl{sub 2} and Ca(NO{sub 3}){sub 2} in CDCl{sub 3}. Previous chiroptical studies of these and similar crown complexes by circularly polarized luminescence (CPL), total luminescence (TL), and circular dichroism (CD) spectroscopy have shown that the macrocycle asymmetric carbons in these complexes constrain the ring such that the sense of the ring twist in the S chiral ring complexes is opposite to that in the R chiral ring complexes. These studies have also shown that there is an added chirality element in the di- and trivalent (alkaline earth and lanthanide metal, respectively) nitrate complexes of I and II associated with the twist of the nitrate anions relative to one another as they sterically ...

1989-10-04

329

Can intensity-modulated radiation therapy of the paraaortic region overcome the problems of critical organ tolerance?  

Energy Technology Data Exchange (ETDEWEB)

Background and purpose: the recent RTOG guidelines for future clinical developments in gynecologic malignancies included the investigation of dose escalation in the paraaortic (PO) region which is, however, very difficult to target due to the presence of critical organs such as kidneys, liver, spinal cord, and digestive structures. The aim of this study was to investigate intensity-modulated radiotherapy's (IMRT) possibilities of either increasing, in a safe way, the dose to 50-60 Gy in case of macroscopic disease or decreasing the dose to organs at risk (OR) when treatment is given in an adjuvant setting. Material and methods: the dosimetric charts of 14 patients irradiated to the PO region at the department of radiation oncology, university hospital of Liege, Belgium, in 2000 were analyzed in order to compare six-field conformal external-beam radio-therapy (CEBR) and five-beam IMRT approaches. Both CEBR and IMRT investigations were planned to ...

2005-03-01

330

Investigations of biomimetic light energy harvesting pigments  

Energy Technology Data Exchange (ETDEWEB)

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Nature uses chlorophyll and other porphyrinic pigments to capture and transfer light energy as a preliminary step in photosynthesis. The design of synthetic assemblies of light harvesting and energy directing pigments has been explored through synthesis and characterization of porphyrin oligomers. In this project, pigment electronic and vibrational structures have been explored by electrochemistry and dynamic and static optical measurements. Transient absorption data reveal energy transfer between pigments with lifetimes on the order of 20--200 picoseconds, while Raman data reveal that the basic porphyrin core structure is unperturbed relative to the individual monomer units. These two findings, along with an extensive series of experiments on the oxidized oligomers, reveal that ...

1998-12-01

331

Electrochemical properties of Cu{sub 2}O/Cu composite particles prepared by a novel and facile method  

Energy Technology Data Exchange (ETDEWEB)

In this study, Cu{sub 2}O/Cu composite particles were synthesized using an innovative chemical reduction method without any template and surfactant. X-ray diffraction (XRD) analysis revealed that the product mainly consisted of Cu{sub 2}O phase coexisting with a Cu phase. FE-SEM images showed that the octahedral shaped particles were Cu{sub 2}O. The electrochemical performance of the Cu{sub 2}O/Cu particles was investigated with regards to the working electrode material in alkaline solution. The particles had a maximum discharge capacity of 222.9 mAh/g at a discharge current density of 60 mA/g and a high value of 109.1 mAh/g after 50 charge-discharge cycles. Cyclic voltammetry revealed that the reaction between Cu{sub 2}O and Cu is the major electrochemical reaction during the charging and discharging process. Electrochemical impedance spectroscopy revealed that the formation of Cu{sub 2}O on the surface of Cu particles ...

2010-07-01

332

Seasonal variations of Zn, Cu, As and Mo in arsenic-rich stream at the Mokrsko gold deposit, Czech Republic  

British Library Electronic Table of Contents (United Kingdom)

Monthly sampling of slightly alkaline arsenic-rich stream in the Mokrsko gold deposit revealed seasonal variations in dissolved Zn, Cu, As and Mo. Concentrations of trace metal cations (Zn, Cu) increased as much as 330 and 178%, respectively, from minimum mean values at autumn to maximum mean values at spring. In contrast, concentrations of trace element oxyanions (As, Mo) revealed opposite seasonal pattern with increase to 189% (As) and 123% (Mo) during summer?autumn, indicating that in-stream biogeochemical process(es) played the main role in controlling the seasonal variations of these trace elements. The trace elements were mainly scavenged by low crystalline Mn oxyhydroxide and Fe oxyhydroxide (ferrihydrite). Results are consistent with sorption and coprecipitation processes controlli...

2011-01-01

333

Primates do not spontaneously use shape properties for object individuation: a competence or a performance problem?  

British Library Electronic Table of Contents (United Kingdom)

Several recent studies have documented that non-human primates can individuate objects according to property and/or kind information in much the same way as human infants do from around one year of age when they begin to acquire language. Some studies suggest, however, that only some properties are used for the individuation of food items: color, but not shape. The present study investigated whether these findings reveal a true competence problem with shape properties in the food domain or whether they merely reveal a performance problem (e.g., lack of attention to shapes). We tested 25 great apes (chimpanzees, bonobos and gorillas) in two food individuation tasks. We manipulated subjects? experience with differences in color and shape properties of food items. Results indicated (i) that a...

2011-01-01

334

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

335

Nanowires of silicon carbide and 3D SiC/C nanocomposites with inverse opal structure  

International Nuclear Information System (INIS)

Synthesis, morphology, structural and optical characteristics of SiC NWs and SiC/C nanocomposites with an inverse opal lattice have been investigated. The samples were prepared by carbothermal reduction of silica (SiC NWs) and by thermo-chemical treatment of opal matrices (SiC/C) filled with carbon compounds which was followed by silicon dioxide dissolution. It was shown that the nucleation of SiC NWs occurs at the surface of carbon fibers felt. It was observed three preferred growth direction of the NWs: [111], [110] and [112]. HRTEM studies revealed the mechanism of the wires growth direction change. SiC/C- HRTEM revealed in the structure of the composites, except for silicon carbide, graphite and amorphous carbon, spherical carbon particles containing concentric graphite shells (onion-like particles).

2011-07-07

336

Molecular Characterization of Coprophilous Fungal Communities Reveals Sequences Related to Root-Associated Fungal Endophytes  

British Library Electronic Table of Contents (United Kingdom)

This paper reports the use of molecular methods to characterize the coprophilous fungal communities (CFC) that inhabit the dung of four species of mammalian herbivores at two sites, Sevilleta National Wildlife Refuge (SNWR) in New Mexico and Wind Cave National Park (WCNP) in South Dakota. Results reveal that CFC from domesticated cattle (Bos taurus) at SNWR, and bison (Bison bison) and black-tailed prairie dogs (Cynomys ludovicianus) at WCNP were diverse but dominated primarily by members within eight taxonomic orders, including the rarely cultured and anaerobic order Neocallimastigales. In addition, 7.7% (138 of 1,788) of the sequences obtained from all dung samples were at least 97% similar to root-associated fungal (RAF) sequences previously described from blue grama (Bouteloua gracilis...

2011-01-01

337

Microstructural aspects of the corrosion of Alloy 800  

International Nuclear Information System (INIS)

Transmission electron microscopy studies on solution-annealed Alloy 800 revealed small (100-200 nm), spherical-shaped titanium carbide (face centered cubic structure) and large (200 nm-5 #mu#m), faceted titanium nitride (hexagonal structure) particles randomly distributed in the austenite matrix. The volume fraction of former particles was found to be greater than that of the latter. Corrosion studies of the alloy in acidic, chlorides and acidic chloride environments at room temperature indicated that the passivity of Alloy 800 was adversely affected by the addition Cl"- ions. X-ray photoelectron spectroscopy revealed that the surface film formed on the alloy at the onset of passivity consisted of Cr"3"+ (as Cr_2O_3), without any Fe"3"+/Fe"2"+ or Ni"2"+. Scanning electron microscopy studies indicated initiation of pitting at large, faceted particles, not at small, spherical-shaped ones.

2004-12-01

338

Metallurgical Investigation of a Prematurely Failed Concentric Reducer Tube Used in a Hot-Rolling Mill  

British Library Electronic Table of Contents (United Kingdom)

A concentric reducer tube, which was a part of the top exit roughing hydraulic descaler in a hot strip mill failed prematurely under working pressure. A detailed metallurgical investigation comprising physical examination, optical microscopy, scanning electron microscopy, and electron probe microanalysis was carried out to find out the genesis of the failure. Physical examination revealed cracks located symmetrically around the circumference of the tube that ran along its full length, up to the weld beads at both ends. Optical microscopy of etched samples revealed a banded ferrite-pearlite structure and the existence of forging folds near the change-in-section(160? fillets). Cracks were found to initiate from these forging folds. No structural abnormalities were found in the weld beads and...

2007-01-01

339

Laparoscopic approach of a nonparasitic splenic cyst; Abordagem videolaparoscopica de cisto esplenico nao parasitario  

Energy Technology Data Exchange (ETDEWEB)

A rare case of primary splenic cyst is shown in a young woman who had a left subcostal abdominal pain. Abdominal echography and CT scan revealed a cyst of the anterior aspect of the spleen. A sorologic test for hidatic disease was negative. On the basis of a presumed diagnostic of nonparasitic cyst, the patient was referred to a laparoscopic decapsulation with excision of the cysts wall not covered by splenic tissue. The patient was discharged 24 hours later. Histological report revealed epidermoid cyst. The laparoscopic approach has being recently considered an effective and less invasive alternative in the treatment of splenic diseases. We demonstrated that it should be considered for the treatment of splenic cysts present in a superficial location, with the advantage of organ preservation. (author)

2000-10-01

340

Investigation of weld cracking in alloy 800  

Energy Technology Data Exchange (ETDEWEB)

The subscale Varestraint test has been used to determine the relative hot cracking susceptibility of the fusion zone in four commercial heats of alloy 800. Although all four heats were susceptible to cracking, one heat exhibited a significant increase in cracking relative to the other three. Optical metallography revealed that nearly all the cracking was localized along fusion zone grain boundaries. Microprobe analysis of the grain boundaries detected high concentrations of titanium, silicon, and niobium resulting from partitioning during solidification. The fusion zone hot cracking mechanism in alloy 800 involves the complex interaction of titanium, silicon, niobium, and carbon along the solidification boundaries. SEM and Auger analyses of the hot crack fracture surfaces revealed the presence of (Ti, Nb)-rich carbides, suggesting that these particles precipitate from the liquid which solidifies last on the fracture surface. 23 references.

1984-03-01

341

Effect of #gamma#-irradiation on commercial polypropylene based mono and multi-layered retortable food packaging materials  

International Nuclear Information System (INIS)

Irradiation processing of food in the prepackaged form may affect chemical and physical properties of the plastic packaging materials. The effect of #gamma#-irradiation doses (2.5-10.0 kGy) on polypropylene (PP)-based retortable food packaging materials, were investigated using Fourier transform infrared (FTIR) spectroscopic analysis, which revealed the changes happening to these materials after irradiation. The mechanical properties decreased with irradiation while oxygen transmission rate (OTR) was not affected significantly. Colour measurement indicated that Nylon 6 containing multilayer films became yellowish after irradiation. Thermal characterization revealed the changes in percentage crystallinity.

2007-07-01

342

Destructive spondyloarthropathy in hemodialysis patients. Report of four cases and prospective study  

Energy Technology Data Exchange (ETDEWEB)

A destructive spondyloarthropathy is reported in four patients undergoing maintenance hemodialysis for chronic renal disease. In a separate investigation a controlled, prospective radiographic study of the cervical spine revealed this spondyloarthropathy in 4 (15%) of 26 long-term dialysis patients. A single disk level was involved in three patients, and two disc levels were involved in one patient. This spondyloarthropathy correlated with the duration of dialysis but not with the radiographic evidence of renal osteodystrophy or severity of laboratory abnormalities associated with hyperparathyroidism. Three of these four patients also had discovertebral erosions or destruction involving the lumbar spine. Cervical spine flexion views revealed evidence of ligamentous laxity or instability in three (12%) dialysis patients, all with vertebral resorption and disc space narrowing. It is postulated that this instability may contribute to the ...

1988-04-01

343

Decreased semen quality in a male infected with malaria.  

Science.gov (United States)

A 33-year-old male of proven fertility suffered six attacks of malaria while resident in an African country. For this he received anti-malarial drugs. Semen analysis performed after the fourth attack, and repeated during the following 2 years after his return to Israel, revealed severe oligozoospermia, necrozoospermia and occasionally even azoospermia. Immunological examination of the patient revealed an inverse ratio of T-cell subsets and mast cell degranulation in response to palludrin. Twenty-five months after the last attack of malaria a significant improvement was found in semen quality and there was an increase in the ratio of T-helper to T-suppressor cytotoxic cells. These observations indicate that although malaria and its treatment may affect spermatogenesis, recovery may be expected eventually. PMID:3500921

1987-10-01

344

Clinical and ultrasonographic findings, diagnosis and treatment of pyelonephritis in 17 cows  

British Library Electronic Table of Contents (United Kingdom)

The goal of the present study was to describe the clinical, haematological and ultrasonographic findings and treatment of 17 cattle with pyelonephritis. Fifteen cattle had an abnormal general condition, which varied in severity; five animals had signs of colic. The urine was brownish-red in 11 animals and cloudy in 13. Clumps of purulent material were seen in the urine of nine animals and clots of blood in two. The specific gravity was lower than normal in 13 animals and ranged from 1.005 to 1.020. A urine test strip revealed protein in 16 animals, blood in 16 and leukocytes in 12. Bacteriological examination of urine yielded Corynebacterium renale in 11 animals, Arcanobacter pyogenes in two and Escherichia coli in one. Rectal examination revealed abnormalities of the urinary tract in 11 a...

2008-01-01

345

Chemically produced nanostructured ODS-lanthanum oxide-tungsten composites sintered by spark plasma  

British Library Electronic Table of Contents (United Kingdom)

High purity W and W-0.9La2O3 (wt.%) nanopowders were produced by a wet chemical route. The precursor was prepared by the reaction of ammonium paratungstate (APT) with lanthanum salt in aqueous solutions. High resolution electron microscopy investigations revealed that the tungstate particles were coated with oxide precipitates. The precursor powder was reduced to tungsten metal with dispersed lanthanum oxide. Powders were consolidated by spark plasma sintering (SPS) at 1300 and 1400degreeC to suppress grain growth during sintering. The final grain size relates to the SPS conditions, i.e. temperature and heating rate, regardless of the starting powder particle size. Scanning electron microscopy revealed that oxide phases were mainly accumulated at grain boundaries while the tungsten matrix ...

2011-01-01

346

Bulk amorphous and nanocrystalline Al83Fe17 alloys prepared by consolidation of mechanically alloyed amorphous powder  

British Library Electronic Table of Contents (United Kingdom)

In the present work, bulk amorphous and nanocrystalline Al83Fe17 alloys were obtained by consolidation of mechanically alloyed powders. Mechanical alloying of Al-17% Fe powder mixture yielded powder with an amorphous structure. Thermal behaviour of the milling product was examined using differential scanning calorimetry. This investigation revealed that the amorphous phase crystallised above 380^oC. The amorphous powder was compacted under a pressure of 7.7GPa in different conditions: at 380^oC for 600s and at 1000^oC for 180s. Structural investigations of the bulk material revealed that the amorphous structure was retained after consolidation process applied at 380^oC. Compaction under high pressure at 1000^oC caused crystallisation of the amorphous phase and appearance of metastable nano...

2010-01-01

347

Basic uranyl perrhenate and its crystallohydrates  

Energy Technology Data Exchange (ETDEWEB)

UO/sub 2/(OH)xReO/sub 4/xH/sub 2/O, UO/sub 2/(OH)ReO/sub 4/x0.5H/sub 2/O and UO/sub 2/(OH)ReO/sub 4/ were produced and their physical and chemical properties were studied for the first time. The chemical analysis was carried out and pycnometric density of the initial crystallohydrate and basic uranyl anhydrous perrhelate wos determined. The two-step mechanism of the dehydration of uranyl hydroxoperrhenate monohydrate was revealed. Values of interplane distances were calculated for a number of roentgenogram lines of the basic uranyl perrhenate and its crystallohydrates. IR spectra of all revealed compounds in the region of 4000-250 cm/sup -1/ were studied.

1982-11-01

348

Applications of environmental scanning electron microscopy (ESEM) in the study of novel drying latex films  

Energy Technology Data Exchange (ETDEWEB)

We have employed Environmental Scanning Electron Microscopy (ESEM) and Energy Dispersive X-ray (EDX) analysis to study the microstructural evolution of acrylic latex stabilised with a novel polysaccharide derived from agricultural waste. The analysis revealed that the micro structure of the latex in the 'wet' state consists of individual particles and clusters. Upon evaporation a discontinuous film is formed, with voids present within its structure, which is inconsistent with the conventional descriptions of film formation. Further ESEM examination of 'dry' specimens revealed that aging resulted in the formation of dendritic structures on the surfaces of the latex films, which EDX analysis confirmed to have been formed via crystallisation of salt. The experimental evidence suggests that the clusters, which are part of the structure of the latex, may act as nucleation centres that would allow the dendrites to ...

2008-08-15

349

p16INK4a Suppression by Glucose Restriction Contributes to Human Cellular Lifespan Extension through SIRT1-Mediated Epigenetic and Genetic Mechanisms  

UK PubMed Central (United Kingdom)

Although caloric restriction (CR) has been shown to increase lifespan in various animal models, the mechanisms underlying this phenomenon have not yet been revealed. We developed an in vitro...Full Text Available

350

What is `that'?  

British Library Electronic Table of Contents (United Kingdom)

Davidsons paratactic account of indirect speech exploits the fact that `that' can be either a demonstrative pronoun or a subordinating conjunction. Davidson thinks that the fact that it is plausible to think that it inherited the latter function from the former lends support to his account. However, in other languages the two functions are performed by unrelated words, which makes the account impossible to apply to them. I argue that this shows that, rather than revealing the underlying form of indirect reports, the account reflects only a quirk of English.

2011-01-01

351

Use of endobronchial one-way valves reveals questions on etiology of spontaneous pneumothorax: report of three cases  

UK PubMed Central (United Kingdom)

Spontaneous pneumothoraces are believed to arise when air from the supplying airway exit via a ruptured visceral pleural bleb into the pleural cavity. Endobronchial one-way valves (EBVs) allow air exit...Full Text Available

352

Turgor Regulation in Osmotically Stressed Arabidopsis Epidermal Root Cells. Direct Support for the Role of Inorganic Ion Uptake as Revealed by Concurrent Flux and Cell Turgor Measurements1  

UK PubMed Central (United Kingdom)

Hyperosmotic stress is known to significantly enhance net uptake of inorganic ions into plant cells. Direct evidence for cell turgor recovery via such a mechanism, however, is still lacking. In the...Full Text Available

2002-05-01

353

True aneurysm originating from the costocervical trunk: surgical excision for recurrence after successful proximal coil embolization.  

Science.gov (United States)

A rare, true aneurysm of a branch of the right subclavian artery is described. Transcatheter coil embolization of the feeder artery was successful in obliterating blood flow into the aneurysm and the mass reduced in size. However, the aneurysm reenlarged over the next week of follow-up due to development and enlargement of the collateral vascular network. Extirpation of the aneurysm was performed. Histopathological examination revealed a true aneurysm. PMID:11833847

2002-01-01

354

Thermographic studies of the interaction between hydrolyzed polyacrylonitrile and Ca/sup 2 +/, Fe/sup 3 +/, Cu/sup 2 +/ ions  

Energy Technology Data Exchange (ETDEWEB)

Reasons were revealed for the fresh water resistance of sediments of hydrolyzed polyacrylonitrile obtained from interaction of it with Fe/sup 3 +/, Ca/sup 2 +/ and Cu/sup 2 +/ cations which are in the saline solutions of these metals.

1982-01-01

355

The effects of high voltage transmission lines on the health of adjacent resident populations  

Energy Technology Data Exchange (ETDEWEB)

A community health survey of 438 individuals was taken to detect health problems related to high voltage electrical transmission among an adjacent residential population. Results revealed no significant or consistent relationships between exposure to a high voltage DC power line and the perceived health problems that were measured. The sample was not, however, large enough to draw statistically significant conclusions regarding possible health effects with a very low incidence.

1984-01-01

356

Tailored airfoils for vertical axis wind turbines  

Energy Technology Data Exchange (ETDEWEB)

The evolution of a family of airfoil sections designed to be used as blade elements of a vertical axis wind turbine (VAWT) is described. This evolution consists of extensive computer simulation, wind tunnel testing and field testing. The process reveals that significant reductions in system costs-of-energy and increases in fatigue lifetime may be expected for VAWT systems using these blade elements.

1984-11-01

357

Synthesis and physicochemical properties of iron (2) perrhenates  

Energy Technology Data Exchange (ETDEWEB)

By dissolution of iron (2) carbonate in rhenium acid iron (2) perrhenate of the Fe(ReO/sub 4/)/sub 2/x4H/sub 2/O composition is obtained. By the method of thermal analysis the limits of tetra-, dihydrate and anhydrous iron (2) perrhenate stability are revealed. By means of X ray phase and IR spectroscopic analysis methods modification of structure in the process of synthesized salt dehydration is shown.

1983-01-01

358

Surface photometry and the structure of elliptical galaxies  

International Nuclear Information System (INIS)

Surface photometry of bulges and elliptical galaxies is reviewed. The properties of cores and nuclei as revealed by improvements in seeing and the use of CCDs are examined, and newly discovered structural details such as dust, shells, and dynamical subsystems which show the importance of accretion events in galactic evolution are addressed. Improved constraints on galaxy formation resulting from better measurements of parameter scaling laws are discussed, and accurate measurements of departures from elliptical isophotes and of color gradients obtained with CCDs are considered.

359

Structure of an accelerator island with one step on double period of conserving area mapping  

International Nuclear Information System (INIS)

The structure of the P-2, S-1 accelerator mode with one step, S-1, on double period, P-2 for systems, described by the Harper mapping as well as by standard mapping, is analyzed. Detailed analysis of stability criteria is given and comparison with the results of numerical analysis is performed. Three-period compression of the P-2, S-1 island is revealed in the standard mapping. Refs. 7, figs. 7.

360

Structure analysis of ferrite in deformed pearlitic steel by means of X-ray diffraction method with synchrotron radiation  

Energy Technology Data Exchange (ETDEWEB)

Structure of ferrite in drawn pearlitic steel containing 0.9 mass% C was investigated with X-ray diffraction technique using synchrotron radiation. In the detailed analysis of diffraction peaks of ferrite during the drawing process, it was experimentally revealed that the transformation of ferrite from bcc to bct due to the supersaturation of carbon in ferrite of heavily drawn pearlitic steel.

2004-07-15

361

Structure analysis of ferrite in deformed pearlitic steel by means of X-ray diffraction method with synchrotron radiation  

International Nuclear Information System (INIS)

Structure of ferrite in drawn pearlitic steel containing 0.9 mass% C was investigated with X-ray diffraction technique using synchrotron radiation. In the detailed analysis of diffraction peaks of ferrite during the drawing process, it was experimentally revealed that the transformation of ferrite from bcc to bct due to the supersaturation of carbon in ferrite of heavily drawn pearlitic steel.

2004-07-01

362

Structural and Functional Investigations of Matrilin-1 A-domains Reveal Insights into Their Role in Cartilage ECM Assembly*  

UK PubMed Central (United Kingdom)

Matrilin-1 is expressed predominantly in cartilage and co-localizes with matrilin-3 with which it can form hetero-oligomers. We recently described novel structural and functional features of the matrilin-3...Full Text Available

2010-10-29

363

Structural analysis of covalently labeled estrogen receptors by limited proteolysis and monoclonal antibody reactivity  

International Nuclear Information System (INIS)

The authors have used limited proteolysis of affinity-labeled estrogen receptors (ER), coupled with antireceptor antibody immunoreactivity, to assess structural features of ER and the relatedness of ER from MCF-7 human breast cancer and rat uterine cells. MCF-7 ER preparations covalently labeled with ["3H]tamoxifen aziridine (["3H]TAZ) were treated with trypsin (T), #alpha#-chymotrypsin (C), or Staphylococcus aureus V8 protease prior to electrophoresis on sodium dodecyl sulfate gels. Fluorography revealed a distinctive ladder of ER fragments containing TAZ for each protease generated from the M/sub r/ 66,000 ER. Immunoblot detection with the primate-specific antibody D75P3#gamma# revealed that all immunoreactive fragments corresponded to TAZ-labeled fragments but that some small TAZ-labeled fragments were no longer immunoreactive. In contrast, use of the antibody H222SP#gamma# revealed a correspondence between TAZ-labeled ...

364

Structural Chemistry of Human SET Domain Protein Methyltransferases  

Science.gov (United States)

There are about fifty SET domain protein methyltransferases (PMTs) in the human genome, that transfer a methyl group from S-adenosyl-L-methionine (SAM) to substrate lysines on histone tails or other peptides. A number of structures in complex with cofactor, substrate, or inhibitors revealed the mechanisms of substrate recognition, methylation state specificity, and chemical inhibition. Based on these structures, we review the structural chemistry of SET domain PMTs, and propose general concepts towards the development of selective inhibitors.

2011-08-22

365

Spin Modulation in Semiconductor Lasers  

CERN Document Server

We provide an analytic study of the dynamics of semiconductor lasers with injection (pump) of spin-polarized electrons, previously considered in the steady-state regime. Using complementary approaches of quasi-static and small signal analyses, we elucidate how the spin modulation in semiconductor lasers can improve performance, as compared to the conventional (spin-unpolarized) counterparts. We reveal that the spin-polarized injection can lead to an enhanced bandwidth and desirable switching properties of spin-lasers.

2010-01-01

366

Single Particle Tracking of ?7 Nicotinic AChR in Hippocampal Neurons Reveals Regulated Confinement at Glutamatergic and GABAergic Perisynaptic Sites  

UK PubMed Central (United Kingdom)

α7 neuronal nicotinic acetylcholine receptors (α7-nAChR) form Ca2+-permeable homopentameric channels modulating cortical network activity and cognitive processing....Full Text Available

367

Simulations of dual morphology in spiral galaxies  

CERN Document Server

Gas and stars in spiral galaxies are modelled with the DUAL code, using hydrodynamic and N-body techniques. The simulations reveal morphological differences mirroring the dual morphologies seen in B and K' band observations of many spiral galaxies. In particular, the gaseous images are more flocculent with lower pitch angles than the stellar images, and the stellar arm-interarm contrast correlates with the degree of morphological decoupling.

2003-01-01

368

Sequence analysis of two alleles reveals that intra-and intergenic recombination played a role in the evolution of the radish fertility restorer (Rfo)  

UK PubMed Central (United Kingdom)

BackgroundLand plant genomes contain multiple members of a eukaryote-specific gene family encoding proteins with pentatricopeptide repeat (PPR) motifs. Some PPR proteins were shown...Full Text Available

369

Search for magnetic rotation in {sup 202}Pb and {sup 203}Pb  

Energy Technology Data Exchange (ETDEWEB)

High-spin states in {sup 202}Pb and {sup 203}Pb have been investigated by in-beam {gamma}-ray spectroscopy following the reaction {sup 198}Pt({sup 9}Be,xn). A search for magnetic rotational bands in these isotopes confirmed one of the two bands previously assigned to {sup 202}Pb and revealed a new band in this isotope. No evidence for magnetic rotation has been found in {sup 203}Pb. (orig.)

2000-11-01

370

SOLERAS - Solar Controlled Environment Agriculture Project. Final report, Volume 4. Saudi Engineering Solar Energy Applications System Design Study  

Energy Technology Data Exchange (ETDEWEB)

Literature summarizing a study on the Saudi Arabian solar controlled environment agriculture system is presented. Specifications and performance requirements for the system components are revealed. Detailed performance and cost analyses are used to determine the optimum design. A preliminary design of an engineering field test is included. Some weather data are provided for Riyadh, Saudi Arabia. (BCS)

1985-01-01

371

Reactive metal brazing of aluminum nitride  

Energy Technology Data Exchange (ETDEWEB)

The addition of titanium to eutectic braze compositions causes these alloys to readily wet and bond to A1N ceramics. Electron microscopic characterizations of the metal-ceramic interfaces reveal the presence of TiN, along with other Ti- and Al-containing phases. The formation of such interfacial reaction products is an additional thermodynamic driving force for the creation of useful metal-ceramic bonds. 12 refs., 4 figs., 1 tab.

1990-01-01

372

Rapid Dissemination and Diversity of CTX-M Extended-Spectrum ?-Lactamase Genes in Commensal Escherichia coli Isolates from Healthy Children from Low-Resource Settings in Latin America?  

UK PubMed Central (United Kingdom)

A survey carried out in 2005 among members of a healthy population of children living in Bolivia and Peru revealed that fecal carriage of Escherichia coli strains resistant to expanded-spectrum...Full Text Available

2007-08-01

373

Polyadenylated H3 histone transcripts and H3 histone variants in alfalfa.  

UK PubMed Central (United Kingdom)

Histone H3 mRNAs were found in polyA(+) fractions of total RNA prepared from alfalfa plants, calli and somatic embryos. The sequence analysis of cDNAs revealed the presence of a polyA tail on independent...Full Text Available

1989-04-25

374

Plant Sulphur Nutrition  

Environmental Research Database

DescriptionThe recent sequencing of the complete genomes of several streptomycete species revealed the presence of a large number of cryptic' secondary metabolic gene clusters, and led to the realisation that these organisms have the ability to produce many more natural products than had previously been recognised. One of the aims of our work is to identify the physiological signals and regulatory mechanisms responsible for the activation of these 'cryptic' pathways, thus unleashing the full biosynthetic p [continued...

2010-01-31

375

Phase-plate electron microscopy: a novel imaging tool to reveal close-to-life nano-structures  

UK PubMed Central (United Kingdom)

After slow progress in the efforts to develop phase plates for electron microscopes, functional phase plate using thin carbon film has been reported recently. It permits collecting high-contrast images...Full Text Available

2009-03-01

376

Percent G+C Profiling Accurately Reveals Diet-Related Differences in the Gastrointestinal Microbial Community of Broiler Chickens  

UK PubMed Central (United Kingdom)

Broiler chickens from eight commercial farms in Southern Finland were analyzed for the structure of their gastrointestinal microbial community by a nonselective DNA-based method, percent G+C-based...Full Text Available

2001-12-01

377

Passivity behavior of melt-spun Mg-Y Alloys  

Energy Technology Data Exchange (ETDEWEB)

Several Mg-Y binary ribbons with Y content up to {approx}17.9 at.% were fabricated by melt-spinning. X-ray diffraction (XRD) revealed that the phase structure changes with increasing Y content from extended solid solution to partially amorphous, and then fully intermetallic Mg{sub 24}Y{sub 5}. Anodic potentiodynamic polarization performed in 0.01 M NaCl electrolyte (pH=12) revealed improved anodic passivity behavior compared to pure Mg for all the Mg-Y alloys. X-ray photoelectron spectroscopy (XPS) revealed that the improved passivity of Mg-Y was more related to the elemental oxidation state rather than the concentration of the surface components. To study the effect of Cl{sup -} ion on the passivity behavior, anodic potentiodynamic and potentiostatic polarization were performed on Mg-17.9 at.% Y in alkaline (pH=12) NaCl electrolytes containing Cl{sup -} ion in the concentration range from 0.00 to 0.50 M. The passive films ...

2003-12-15

378

Passivity behavior of melt-spun Mg-Y Alloys  

International Nuclear Information System (INIS)

Several Mg-Y binary ribbons with Y content up to #approx#17.9 at.% were fabricated by melt-spinning. X-ray diffraction (XRD) revealed that the phase structure changes with increasing Y content from extended solid solution to partially amorphous, and then fully intermetallic Mg_2_4Y_5. Anodic potentiodynamic polarization performed in 0.01 M NaCl electrolyte (pH=12) revealed improved anodic passivity behavior compared to pure Mg for all the Mg-Y alloys. X-ray photoelectron spectroscopy (XPS) revealed that the improved passivity of Mg-Y was more related to the elemental oxidation state rather than the concentration of the surface components. To study the effect of Cl"- ion on the passivity behavior, anodic potentiodynamic and potentiostatic polarization were performed on Mg-17.9 at.% Y in alkaline (pH=12) NaCl electrolytes containing Cl"- ion in the concentration range from 0.00 to 0.50 M. The passive films formed in 0.01 M ...

2003-12-15

379

PIXE analysis of trace elements in relation to chlorophyll concentration in Plantago ovata Forsk  

Energy Technology Data Exchange (ETDEWEB)

Plantago ovata Forsk - an economically important medicinal plant - was analyzed for trace elements and chlorophyll in a study of the effects of gamma radiation on physiological responses of the seedlings. Proton-induced X-ray emission (PIXE) technique was used to quantify trace elements in unirradiated and gamma-irradiated plants at the seedling stage. The experiments revealed radiation-induced changes in the trace element and chlorophyll concentrations.

2010-03-15

380

PIV measurements of flow structures in a spray dryer  

DEFF Research Database (Denmark)

Stereoscopic Particle Image Velocimetry (PIV) measurements are made in horizontal planes in a simplified scale model of a spray dryer using water as fluid. The sample rate was sufficient to resolve phenomena at lower frequencies. Data reveal asymmetric velocity fields in both mean fields and dynamics. Data were analysed using Proper Orthogonal Decomposition (POD). An important periodic event is an elongation of the jet core cross section that results in a downstream displacement of the jet towards the chamber wall.

2011-01-01

381

PET and MR imaging in a neuro-Behcet syndrome  

Energy Technology Data Exchange (ETDEWEB)

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

1989-11-01

382

On some problems caused by wavelet filtering in calculated spectra  

Energy Technology Data Exchange (ETDEWEB)

It is shown that de-noising a measured time signal by wavelet technique produces a rather good result in time domain, while it has unwanted consequences in spectrum estimation. Therefore it can be used for reconstruction of the picture of the physical process, but it should be avoided, when the aim is to reveal eigenfrequencies or transient behaviour of the spectra.

1999-08-01

383

Oil refinery waste disposal methods, quantities and costs, 1993 survey  

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the information gathered by CONCAVE in a 1993 survey of waste generation and disposal by the oil refineries in Western Europe. The survey covered the types of waste produced, their quantities, disposal routes and costs of disposal. The results are compared with those from a 1986 survey, but because of the increased numbers of refineries reporting, comparison is difficult. The survey revealed wide variations in disposal costs depending on waste type and local circumstances.

1995-06-01

384

Nucleotide sequence and genetic analysis of a 13.1-kilobase-pair Pseudomonas denitrificans DNA fragment containing five cob genes and identification of structural genes encoding Cob(I)alamin adenosyltransferase, cobyric acid synthase, and bifunctional cobinamide kinase-cobinamide phosphate guanylyltransferase.  

UK PubMed Central (United Kingdom)

A 13.1-kb DNA fragment carrying Pseudomonas denitrificans cob genes has been sequenced. The nucleotide sequence and genetic analysis revealed that this fragment contained five different cob genes named...Full Text Available

1991-10-01

385

Nonlinear air-coupled emission: The signature to reveal and image microdamage in solid materials  

International Nuclear Information System (INIS)

It is shown that low-frequency elastic vibrations of near-surface planar defects cause high-frequency ultrasonic radiation in surrounding air. The frequency conversion mechanism is concerned with contact nonlinearity of the defect vibrations and provides efficient generation of air-coupled higher-order ultraharmonics, ultrasubharmonics, and combination frequencies. The nonlinear air-coupled ultrasonic emission is applied for location and high-resolution imaging of damage-induced defects in a variety of solid materials.

2007-12-17

386

Noise Shielding Using Acoustic Metamaterials  

International Nuclear Information System (INIS)

We exploit theoretically a class of rectangular cylindrical devices for noise shielding by using acoustic metamaterials. The function of noise shielding is justified by both the far-field and near-field full-wave simulations based on the finite element method. The enlargement of equivalent acoustic scattering cross sections is revealed to be the physical mechanism for this function. This work makes it possible to design a window with both noise shielding and air flow. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

2010-03-15

387

Multiway real-time PCR gene expression profiling in yeast Saccharomyces cerevisiae reveals altered transcriptional response of ADH-genes to glucose stimuli  

UK PubMed Central (United Kingdom)

BackgroundThe large sensitivity, high reproducibility and essentially unlimited dynamic range of real-time PCR to measure gene expression in complex samples provides the opportunity...Full Text Available

388

Molecular recognition of nitrated fatty acids by PPAR[gamma  

Energy Technology Data Exchange (ETDEWEB)

Peroxisome proliferator activated receptor-{gamma} (PPAR{gamma}) regulates metabolic homeostasis and adipocyte differentiation, and it is activated by oxidized and nitrated fatty acids. Here we report the crystal structure of the PPAR{gamma} ligand binding domain bound to nitrated linoleic acid, a potent endogenous ligand of PPAR{gamma}. Structural and functional studies of receptor-ligand interactions reveal the molecular basis of PPAR{gamma} discrimination of various naturally occurring fatty acid derivatives.

2010-03-08

389

Meta-Analysis for Genome-Wide Association Study Identifies Multiple Variants at the BIN1 Locus Associated with Late-Onset Alzheimer's Disease  

UK PubMed Central (United Kingdom)

Recent GWAS studies focused on uncovering novel genetic loci related to AD have revealed associations with variants near CLU, CR1, PICALM and BIN1....Full Text Available

390

Measurement of radiative, Auger, and nonradiative currents in 1. 3-. mu. m InGaAsP buried heterostructure lasers  

Energy Technology Data Exchange (ETDEWEB)

Frequency response measurements are used to determine the carrier lifetime of 1.3-..mu..m InGaAsP buried heterostructure lasers between 1 mA and threshold. The data confirm previous results on the radiative and Auger recombination coefficients and reveal the presence of a nonradiative current which dominates at low currents and contributes 4 mA at threshold.

1987-02-09

391

Magnetic resonance imaging in acute intractional tuberculosis  

International Nuclear Information System (INIS)

We reported three cases of acute intracranial tuberculosis including miliary tuberculosis, basal meningitis, tuberculomas and neuritis of cranial nerves. All patients had native and contrast enhanced CT and MRI scans. MRI revealed more granulomas and a better imaging contrast in the detection of basal meningitis. Neuritis was diagnosed only with the MRI. MRI scans should be prefered as the imaging procedure in clinically presumed intracranial tuberculosis. (orig.).

392

Magnetic domains in martensite of Ni-Mg-Ga alloy  

International Nuclear Information System (INIS)

The structural changes attendant on intermartensitic transformation in a Ni-Mg-Ga shape memory alloy are considered using magneto-optical visualization with the help of ferrite-garnet monocrystalline films. It is established that on the intermartensitic transformation the complete reorganization of martensite macrostructure fails. Martensite crystals resulted from the basic transformation change somewhat their sizes on intermartensitic transition. The existence of large-scale labyrinth magnetic domain structure is revealed

2006-05-01

393

Kv1.1 potassium channel deficiency reveals brain-driven cardiac dysfunction as a candidate mechanism for sudden unexplained death in epilepsy(SUDEP)  

UK PubMed Central (United Kingdom)

Mice lacking Kv1.1 Shaker-like potassium channels encoded by the Kcna1 gene exhibit severe seizures and die prematurely. The channel is widely expressed in...Full Text Available

2010-04-14

394

Investigation of morphology and chemical composition of self-organized semiconductor quantum dots and wires by X-ray scattering  

International Nuclear Information System (INIS)

X-ray scattering methods suitable for the investigation of the morphology and chemical composition of self-organized quantum dots and quantum wires are reviewed. Their application is demonstrated in experimental examples showing that a combination of small angle X-ray scattering with high-resolution X-ray diffraction can reveal both the shape and the chemical composition of the self-organized objects. (author)

2001-09-23

395

Investigation of Moessbauer radiation diffraction on Fe/sub 3/BO/sub 6/ monocrystal. Nuclear transition interference  

Energy Technology Data Exchange (ETDEWEB)

Energy spectra of the Bragg reflection of the Moessbauer ..gamma..-radiation from the /sup 57/Fe/sub 3/BO/sub 6/ weakly ferromagnetic monocrystal are studied. A strong effect of the interference transitions in iron nuclei, being in non-equivalent positions, on the spectra form is revealed. The measurement results are compared with theoretical calculations.

1984-05-25

396

Influence of lanthanum (x) concentration on the properties of x/65/35 PLZT electroceramics  

International Nuclear Information System (INIS)

Lead lanthanum zirconate titanate (PLZT) nanopowders with chemical compositions x/65/35 PLZT (x = 6 - 10 mol%) were prepared by sol-gel method. PLZT ceramics was obtained by the conventional sintering method and utilizing the hot pressing method. The investigations of dielectric and ferroelectric measurements of as obtained PLZT ceramics have revealed the influence of lanthanum concentration on the properties of PLZT electroceramics. (author)

2003-09-25

397

Influence of MeV electron irradiation on the properties of by ion implantation hydrogenated polysilicon TFTs  

Energy Technology Data Exchange (ETDEWEB)

The influence of MeV electrons irradiation on the gate oxide layers of hydrogenated polysilicon thin film transistors (TFTs) was investigated by measuring gate leakage currents and threshold voltages. The experimental data revealed a decrease of oxide trap density and increase of positive oxide charge. Improvement in the interface roughness and in the oxide quality near the bottom interface was observed.

2006-02-15

398

Influence of MeV electron irradiation on the properties of by ion implantation hydrogenated polysilicon TFTs  

International Nuclear Information System (INIS)

The influence of MeV electrons irradiation on the gate oxide layers of hydrogenated polysilicon thin film transistors (TFTs) was investigated by measuring gate leakage currents and threshold voltages. The experimental data revealed a decrease of oxide trap density and increase of positive oxide charge. Improvement in the interface roughness and in the oxide quality near the bottom interface was observed.

2006-02-01

399

Immunocytochemical techniques reveal multiple, distinct cellular pools of PtdIns4P and PtdIns(4,5)P2  

UK PubMed Central (United Kingdom)

PtdIns4P is the major precursor for the synthesis of the multifunctional plasma membrane lipid, PtdIns(4,5)P2. Yet PtdIns4P also functions...Full Text Available

2009-08-15

400

Ignition and combustion features of biofuels  

British Library Electronic Table of Contents (United Kingdom)

This paper presents the results of experimental investigations of the ignition and combustion of plant biofuels (wood particles, date stones) and products of their mechanical and thermal treatment (pellets, charcoal) at temperatures typical of the burning process in nonforced furnaces and fixed-bed and fluidized-bed gas producers. The influence of the furnace heat treatment of a fuel on its inflammation and combustion has been revealed. The results have been compared with the known data on the burning of pellets, brown coals, and anthracites and with the calculation by the classical diffusion-kinetic model.

2011-01-01

401

Hyperfine anomaly measurements in francium isotopes and the radial distribution of neutrons  

International Nuclear Information System (INIS)

We have performed precision measurements in a magneto-optical trap of the 7P1/2 hyperfine structure of the isotopes 209-210Fr. The ratio of these hyperfine constants to the previously measured 7S1/2 ground state values reveals a significant hyperfine anomaly. This anomaly results from the different radial dependence of the electron density in the two atomic levels. The measurements are sensitive to changes in the radial distribution of the neutron magnetism.

1999-09-01

402

Hydrogen-induced phase transformations in H-storing alloys of zirconium  

Energy Technology Data Exchange (ETDEWEB)

In this work, the ability of a number of Zr-containing intermetallic compounds with the Zr{sub 2}Me stoichiometry, including Zr{sub 2}Fe, Zr{sub 2}Ni, Zr{sub 2}Co and Zr{sub 4}Fe{sub 2}O{sub 0.6}, to participate in the Hydrogenation-Disproportionation-Desorption-Recombination process was investigated, revealing for the first time that the HDDR route can be employed successfully for all these compounds. 24 refs.

1998-07-01

403

Homozygosity Mapping Reveals Null Mutations in FAM161A as a Cause of Autosomal-Recessive Retinitis Pigmentosa  

UK PubMed Central (United Kingdom)

Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal degenerations caused by mutations in at least 45 genes. Using homozygosity mapping, we identified a ∼4 Mb homozygous region...Full Text Available

2010-09-10

404

Global analysis of estrogen receptor beta binding to breast cancer cell genome reveals an extensive interplay with estrogen receptor alpha for target gene regulation  

UK PubMed Central (United Kingdom)

BackgroundEstrogen receptors alpha (ERα) and beta (ERβ) are transcription factors (TFs) that mediate estrogen signaling and define the hormone-responsive phenotype...Full Text Available

405

Genomic sequence for human prointerleukin 1 beta: possible evolution from a reverse transcribed prointerleukin 1 alpha gene.  

UK PubMed Central (United Kingdom)

We have isolated the human prointerleukin 1 (proIL-1) beta gene from leukocyte and fetal liver libraries. The nucleotide sequence and its gene organization reveals that the proIL-1 beta gene is composed...Full Text Available

1986-10-24

406

Genome-wide analysis reveals rapid and dynamic changes in miRNA and siRNA sequence and expression during ovule and fiber development in allotetraploid cotton (Gossypium hirsutum L.)  

UK PubMed Central (United Kingdom)

BackgroundCotton fiber development undergoes rapid and dynamic changes in a single cell type, from fiber initiation, elongation, primary and secondary wall biosynthesis, to fiber...Full Text Available

2009-01-01

407

Genome structure of cotton revealed by a genome-wide SSR genetic map constructed from a BC1 population between gossypium hirsutum and G. barbadense  

UK PubMed Central (United Kingdom)

BackgroundCotton, with a large genome, is an important crop throughout the world. A high-density genetic linkage map is the prerequisite for cotton genetics and breeding. A genetic...Full Text Available

408

Formation of interphase layers in titanium alloys under repeated loading  

International Nuclear Information System (INIS)

Cyclic strength of #alpha#+#beta#-titanium alloy BT3-1 is studied under load frequencies of 33 and 300 Hz. The increase in the cyclic strength with growing frequency is caused by formation of FCC interphase layers of titanium hydrides. Their formation is one of possible ways of raising the fatigue strength of titanium alloys. Peculiarities of FCC interlayer formation in #alpha#+#beta# phases under loading frequency variation are revealed.

409

Ferromagnetism in Mn-doped GaAs layers: Effects of laser annealing  

Energy Technology Data Exchange (ETDEWEB)

The properties of Mn-doped GaAs layers grown by laser deposition were investigated with measurements of Hall effect and magneto-optical Kerr effect (MOKE). The electrical and magnetic parameters of the layers were defined by growth temperature and quantity of sputtered Mn. It was shown that room-temperature ferromagnetism is revealed by MOKE and, after ruby laser 25 ns pulse annealing, by Hall effect measurements.

2006-05-15

410

Esophageal perforation following bite of inner tube of automobile tyre: An unusual cause of barotrauma  

UK PubMed Central (United Kingdom)

An 8-year-old child presented with severe chest pain and respiratory distress after he accidentally bit an automobile tyre tube which burst into his mouth. The chest radiograph revealed left-sided pneumothorax....Full Text Available

2010-01-01

411

Effects of Temperature on H+ Secretion and Uptake by Excised Flexor Cells during Dark-Induced Closure of Samanea Leaflets 1  

UK PubMed Central (United Kingdom)

Previous studies reveal that dark-induced closure of Samanea leaflets is accompanied by H+ secretion from flexor motor cells. We now report that flexor tissue excised in...Full Text Available

1987-11-01

412

Effect of the hydroxyl-ethyl-cellulose concentration in a silicon wafer polishing slurry on the wafer surface roughness  

International Nuclear Information System (INIS)

The purpose of this study was to reveal the mechanism of wafer touch polishing using a high purity colloidal silica slurry containing organic surfactants such as hydroxyl-ethyl cellulose. The effect of the surfactant concentration on wafer touch polishing was studied to improve the roughness of wafer surfaces after polishing. The haze level and the micro-roughness decreased with decreasing surfactant concentration.

2006-04-01

413

Diversity and Multiplexing Tradeoff in the Uplink of Cellular Systems with Linear MMSE Receiver  

CERN Document Server

In this paper, we extend the diversity and multiplexing tradeoff (DMT) analysis from point-to-point channels to cellular systems to evaluate the impact of inter-cell interference on the system reliability and efficiency. Fundamental tradeoff among diversity order, multiplexing gain and inter-cell interference intensity is characterized to reveal the capability of multiple antennas in cellular systems. And the detrimental effects of the inter-cell interference on the system performance of diversity and multiplexing is presented and analyzed.

2011-01-01

414

Different genetic requirements for anterior RNA localization revealed by the distribution of Adducin-like transcripts during Drosophila oogenesis.  

UK PubMed Central (United Kingdom)

The proteins encoded by polar-localized mRNAs play an important role in cell fate specification along the anteroposterior axis of the Drosophila embryo. The only maternally synthesized mRNA known previously...Full Text Available

1993-03-15

415

Determination of progesterone for reproduction control in cows using a /sup 3/H radioimmunoassay. 1. Methods and choice of testing samples  

Energy Technology Data Exchange (ETDEWEB)

For verification of cow fertility a /sup 3/H radioimmunoassay of progesterone in milk and blood plasma was developed. It is of high specificity and accuracy as well. Extraction of progesterone from milk was facilitated by application of alcohol. Suggested differences in milk and plasma progesterone levels between pregnant and nonpregnant cows could be revealed.

1984-01-01

416

Cutaneous manifestations in brucellosis.  

Science.gov (United States)

Brucellosis is a common worldwide zoonotic disease. Cutaneous manifestations are not specific and affect 1-14% of patients with brucellosis. Here, we describe 49-year-old female with fever and a diffuse maculopapular rash due to Brucella melitensis infection. Histopathology of skin biopsy revealed leukocytoclastic vasculitis; positive blood cultures for B. melitensis established the diagnosis of brucellosis. We provide a review of the relevant literature. PMID:21772606

2011-05-01

417

Computed tomography in migratory disorders of human brain development  

International Nuclear Information System (INIS)

Computed tomographic findings in developmental brain anomalies are more easily classified when the system used is based on embryogenesis related to morphology. Analysis of computed tomographic findings in a series of 154 patients with brain anomalies (Chiari malformation not included) revealed that specific examples of abnormalities occurring in major stages of brain development may be recognized by computed tomography. This paper deals with a group of patients with abnormalities that reflect a disturbance in neuronal migration. (orig.).

418

Complete Dissection of a Hepatic Segment after Blunt Abdominal Injury Successfully Treated by Anatomical Hepatic Lobectomy: Report of a Case  

UK PubMed Central (United Kingdom)

A 21-year-old male patient was transferred to the emergency room of our hospital after suffering seat belt abdominal injury in a traffic accident. Abdominal computed tomography revealed a massive hematoma...Full Text Available

419

Comparative analysis of the ATRX promoter and 5' regulatory region reveals conserved regulatory elements which are linked to roles in neurodevelopment, alpha-globin regulation and testicular function  

UK PubMed Central (United Kingdom)

BackgroundATRX is a tightly-regulated multifunctional protein with crucial roles in mammalian development. Mutations in the ATRX gene cause ATR-X syndrome, an X-linked...Full Text Available

420

Coir fibre toxicity: in vivo and in vitro studies.  

Science.gov (United States)

The biological activity of coir fibre, coir ash and their components were investigated in vitro by measuring the haemolytic activity and macrophage cytotoxicity. In vivo studies carried out by injecting guinea pigs intratracheally with coir fibres resulted in resolving granulomas. The observed haemolytic activity and macrophage cytotoxicity was more marked with coir ash compared with coir fibres. Chemical analysis of coir ash revealed the presence of toxic chemical constituents in appreciable amounts. PMID:6283694

1982-03-01

421

Cloning, sequence analysis and over-expression of the gene for the class II fructose 1,6-bisphosphate aldolase of Escherichia coli.  

UK PubMed Central (United Kingdom)

Nucleotide sequence analysis of the Escherichia coli chromosomal DNA inserted in the plasmid pLC33-5 of the Clarke and Carbon library [Clarke & Carbon (1976) Cell 9, 91-99] revealed the existence...Full Text Available

1989-01-15

422

Clinical and ultrasonographic findings, diagnosis and treatment of pyelonephritis in 17 cows.  

Science.gov (United States)

The goal of the present study was to describe the clinical, haematological and ultrasonographic findings and treatment of 17 cattle with pyelonephritis. Fifteen cattle had an abnormal general condition, which varied in severity; five animals had signs of colic. The urine was brownish-red in 11 animals and cloudy in 13. Clumps of purulent material were seen in the urine of nine animals and clots of blood in two. The specific gravity was lower than normal in 13 animals and ranged from 1.005 to 1.020. A urine test strip revealed protein in 16 animals, blood in 16 and leukocytes in 12. Bacteriological examination of urine yielded Corynebacterium renale in 11 animals, Arcanobacter pyogenes in two and Escherichia coli in one. Rectal examination revealed abnormalities of the urinary tract in 11 animals; there was dilatation of the left ureter and/or enlargement of the left kidney in eight cases, and dilatation of the right ureter and/or enlargement of ...

2007-03-23

423

Carbon effect on the structure and plasticity characteristics of titanium #beta#-alloys  

International Nuclear Information System (INIS)

In this paper a study is made of the structure and mechanical properties of the #beta# alloy system Ti-Mo-Zr-Sn (the composition of which is equivalent to the #beta# III alloy used abroad) containing different amounts of carbon. Study of the #beta#-titanium alloy containing 0.1% C revealed the presence of particles of titanium carbide. Separation of the titanium carbide promotes a reduction in impact strength, an increased tendency toward cold shortness, and poorer workability. (author).

424

Atomic substitution reveals the structural basis for substrate adenine recognition and removal by adenine DNA glycosylase  

Science.gov (United States)

Adenine DNA glycosylase catalyzes the glycolytic removal of adenine from the promutagenic A {center_dot} oxoG base pair in DNA. The general features of DNA recognition by an adenine DNA glycosylase, Bacillus stearothermophilus MutY, have previously been revealed via the X-ray structure of a catalytically inactive mutant protein bound to an A:oxoG-containing DNA duplex. Although the structure revealed the substrate adenine to be, as expected, extruded from the DNA helix and inserted into an extrahelical active site pocket on the enzyme, the substrate adenine engaged in no direct contacts with active site residues. This feature was paradoxical, because other glycosylases have been observed to engage their substrates primarily through direct contacts. The lack of direct contacts in the case of MutY suggested that either MutY uses a distinctive logic for substrate recognition or that the X-ray structure had captured a noncatalytically competent ...

2010-01-14

425

Are there tachyons in extensive air showers?  

International Nuclear Information System (INIS)

The results obtained by studying double-front extensive air showers in which more than 107 particles are contained and in which the fronts are separated by a time interval of #DELTA#t #approx# 100 ns are presented. Serious difficulties in explaining 'delayed' showers are revealed. In this connection, a hypothesis that the 'leading' showers are initiated by tachyons produced in the first interaction of primary particles is proposed.

2010-05-01

426

Application of a Newly Developed ARB Software-Integrated Tool for In Silico Terminal Restriction Fragment Length Polymorphism Analysis Reveals the Dominance of a Novel pmoA Cluster in a Forest Soil  

UK PubMed Central (United Kingdom)

TRF-CUT, an ARB-implemented tool, was developed to predict in silico the terminal restriction fragments of aligned small-subunit rRNA gene or functional gene sequences. Application of this new tool...Full Text Available

2005-03-01

427

Antigenic drift in influenza virus H3 hemagglutinin from 1968 to 1980: multiple evolutionary pathways and sequential amino acid changes at key antigenic sites.  

UK PubMed Central (United Kingdom)

Surveys of the antigenic properties of a wide range of variants of the H3N2 (Hong Kong) influenza virus subtype have revealed complex patterns of variants cocirculating during each of the main epidemic...Full Text Available

1983-10-01

428

Analysis of the murine All-1 gene reveals conserved domains with human ALL-1 and identifies a motif shared with DNA methyltransferases.  

UK PubMed Central (United Kingdom)

A series of translocation break points found in a subset of human acute leukemias have one of the breaks on human chromosome 11q23. This region has recently been cloned and a large gene, ALL-1, with...Full Text Available

1993-07-01

429

Abundances of s-process elements in planetary nebulae: Br, Kr & Xe  

CERN Document Server

We identify emission lines of post-iron peak elements in very high signal-to-noise spectra of a sample of planetary nebulae. Analysis of lines from ions of Kr and Xe reveals enhancements in most of the PNe, in agreement with the theories of s-process in AGB star. Surprisingly, we did not detect lines from Br even though s-process calculations indicate that it should be produced with Kr at detectable levels.

2006-01-01

430

A mechanism for the degradation of superconducting transition temperatures on high energy neutron irradiation in A-15 compounds  

International Nuclear Information System (INIS)

Electron microscopic observations of neutron irradiated Nb_3Sn revealed the presence of highly disordered regions of size approximately 35 A in a much less disordered matrix. This observation is shown to provide a means of explaining quantitatively many superconducting properties of irradiated A-15 compounds. In particular Tsub(c) of the irradiated materials could be easily predicted using the mathematical formulations developed for the proximity effect. (Auth.).

431

A System-Based Comparison of Gene Expression Reveals Alterations in Oxidative Stress, Disruption of Ubiquitin-Proteasome System and Altered Cell Cycle Regulation after Exposure to Cadmium and Methylmercury in Mouse Embryonic Fibroblast  

UK PubMed Central (United Kingdom)

Environmental and occupational exposures to heavy metals such as methylmercury (MeHg) and cadmium (Cd) pose significant health risks to humans, including neurotoxicity. The underlying mechanisms of...Full Text Available

2010-04-01

432

5f electron localization in metallic UPd_3  

International Nuclear Information System (INIS)

The electronic structure of UPd_3 has been determined by means of XPS and BIS experiments. The core level line shapes and the valence band spectra of occupied and empty states clearly reveal the localized character of the 5f electrons in this actinide compound. From these spectra their Coulomb correlation energy is found to be about 2 eV. (author).

433

2DIR spectroscopic studies on cholic acid  

Science.gov (United States)

Based on our cryogenic FT-IR spectroscopic studies of hydrogen bonds in cholic acid, the two-dimensional FT-IR spectroscopy was applied to enhance our understanding of the hydrogen bonds. Fine spectral structures were revealed by asynchronous 2D FT-IR spectra. The co-relationship among various bands was discussed according to the synchronous 2D FT-IR spectra. .

2000-03-01

434

#alpha#-particle irradiation damage and stage I recovery in zinc  

International Nuclear Information System (INIS)

Defects are produced in zinc by 6.1 MeV #alpha#-particle irradiation at 4.2 K and the subsequent recovery between 4.2 and 22 K. No evidence is found for free migration of an interstitial in the temperature range investigated. The recovery spectra reveal a series of substages which are ascribed to recombination of close Frenkel pairs. (author).

435

Wisconsinan-Holocene seismic stratigraphy of the Keathley Canyon Area and vicinity, northwestern Gulf of Mexico  

Science.gov (United States)

The lower continental slope of the northwestern Gulf of Mexico is characterized by a hummocky topography with shallow salt masses interspersed by numerous salt-withdrawal basins containing thick Plio-Pleistocene and older sediments. Analysis of over 7500 km of multichannel seismic reflection data from the Keathley Canyon Area and vicinity defined the Wisconsinan-Holocene sequence and its seismic facies. In interbasinal areas and in the southern part of the study area where salt is shallow, the Wisconsinan-Holocene sequence consists mainly of low-amplitude (LA) facies underlain by strong basal-reflection (SBR) facies. The LA facies occasionally show subtle onlaps against SBR facies and grade upward into a draping pattern. Onlapping LA facies are interpreted to be a lowstand systems tract deposited by widespread low-energy turbidity currents. Draping LA facies at the top may consist of hemipelagic or pelagic sediments. The SBR facies are interpreted to consist of condensed sections ...

1991-03-01

436

Virasoro algebra action on integrable hierarchies and Virasoro contraints in matrix models  

International Nuclear Information System (INIS)

The action of the Virasoro algebra on integrable hierarchies of non-linear equations and on related objects ('Schroedinger' differential operators) is investigated. The method consists in pushing forward the Virasoro action to the wave function of a hierarchy, and then reconstructing its action on the dressing and Lax operators. This formulation allows one to observe a number of suggestive similarities between the structures involved in the description of the Virasoro algebra on the hierarchies and the structure of conformal field theory on the world-sheet. This includes, in particular, an 'off-shell' hierarchy version of operator products and of the Cauchy kernel. In relation to matrix models, which have been observed to be effectively described by integrable hierarchies subjected to Virasoro constraints, I propose to define general Virasoro-constrained hierarchies also in terms of dressing operators, by certain equations which carry the information of the ...

1991-12-01

437

Use of the ADINA (Automatic Dynamic Incremental Nonlinear Analysis) computer code on a COSA II (Computer Codes for Salt) benchmark computer case of the local area - progress report 1990  

International Nuclear Information System (INIS)

The COSA II (computer codes for salt) benchmark problem has been pursued with the ADINA (Automatic Dynamic Incremental Nonlinear Analysis) program code. With the use of this, the code should be validated by means of experimental data and the ability to reproduce real-life calculation results of the KfK (Kernforschungszentrum Karlsruhe/Nuclear Research Center in Karlsruhe) should be proven. A successful validation of the code then forms the foundation stone for the ability to use different calculation problems in the final (ultimate) storage. This also accompanies the consequent reaction of replacing the STEALTH (Solids and Thermal Hydraulics Code for EPRI Adapted from LAGRANGE TOODY and HEMP) program which has a number of program-specific weaknesses compared to the ADINA computer code. In order to reproduce the approximate values from the KfK, the same values have been used. Differences were evident in the discretion and the selection of the initial values for pressure and temperature. ...

438

Towards an objective evaluation of tolerances for beam modeling in a treatment planning system  

International Nuclear Information System (INIS)

The performance of a convolution/superposition based treatment planning system depends on the ability of the dose calculation algorithm to accurately account for physical interactions taking place in the tissue, key components of the linac head and on the accuracy of the photon beam model. Generally the user has little or no control over the performance of the dose calculation algorithm but is responsible for the accuracy of the beam model within the constraints imposed by the system. This study explores the dosimetric impact of limitations in photon beam modeling accuracy on complex 3D clinical treatment plans. A total of 70 photon beam models was created in the Pinnacle(TM) treatment planning system. Two of the models served as references for 6 MV and 15 MV beams, while the rest were created by perturbing the reference models in order to produce specific deviations in specific regions of the calculated dose profiles (central axis and transverse). The beam models were then used to ...

2007-09-21

439

The importance of accurate crystal structure determination of uranium minerals. Pt. 1  

International Nuclear Information System (INIS)

On the basis of accurate crystal structure determination, the mineral phosphuranylite corresponds to the chemical formula KCa(H_3O)_3(UO_2)_7(PO_4)_4O_4.8H_2O. Cmcm, a=15.778 (3)-15.899(2), b=13.702(2)-13.790(5), c=17.253(3)-17.330(3)A, Z=4, D_x=4.575-4.631g cm"-"3, #mu#=287.6-291.1cm"-"1. The presence of potassium (about 1.80wt%K_2O), overlooked until now, has been confirmed by microprobe analysis on samples from four different localities. The best data for structure determination have been obtained by single-crystal X-ray diffraction on specimens from Capoterra, Sardinia, and Bois Noirs, France; here 1453 and 1254 independent reflections, respectively, were used in the refinement, and the corresponding final R index is 0.036 and 0.048. The structure consists of layers of phosphate groups connected with hexagonal, pentagonal and tetragonal dipyramids centered on the U atoms. The Ca and K atoms are located within channels in the uranylphosphate framework, together with water molecules, ...

440

The impact of wet flue gas desulfurization scrubbing on mercury emissions from coal-fired power stations.  

Science.gov (United States)

This article introduces a predictive capability for Hg retention in any Ca-based wet flue gas desulfurization (FGD) scrubber, given mercury (Hg) speciation at the FGD inlet, the flue gas composition, and the sulphur dioxide (SO2) capture efficiency. A preliminary statistical analysis of data from 17 full-scale wet FGDs connects flue gas compositions, the extents of Hg oxidation at FGD inlets, and Hg retention efficiencies. These connections clearly signal that solution chemistry within the FGD determines Hg retention. A more thorough analysis based on thermochemical equilibrium yields highly accurate predictions for total Hg retention with no parameter adjustments. For the most reliable data, the predictions were within measurement uncertainties for both limestone and Mg/lime systems operating in both forced and natural oxidation mode. With the U.S. Environmental Protection Agency's (EPA) Information Collection Request (ICR) database, the quantitative performance was almost as good for ...

2005-07-01

441

Surface activity at the planar interface in relation to the thermodynamics of intermolecular interactions in the ternary system: maltodextrin-small-molecule surfactant-legumin.  

Science.gov (United States)

We report on the effect of potato maltodextrins with variable dextrose equivalent (Paselli SA-2, SA-6 and SA-10) on the surface behavior at the air-water interface of the mixture: legumin+small-molecule surfactant. Distinct in nature small-molecule surfactants (model: sodium salt of capric acid, Na-caprate; and commercially important: a citric acid ester of monoglyceride, CITREM) have been under our consideration. The role of the structure of both of the maltodextrins and the small-molecule surfactants in the effect studied has been elucidated by measurements in a bulk aqueous medium of the enthalpy of their interaction from mixing calorimetry, value of weight average molecular weight of the maltodextrins and the thermodynamics of the pair maltodextrin-solvent and maltodextrin-protein interactions from laser static light scattering. The combined data of mixing calorimetry and light scattering suggest some complex formation between the small-molecule surfactants and the maltodextrins. ...

2001-07-01

442

Stochastic versus deterministic kernel-based superposition approaches for dose calculation of intensity-modulated arcs  

International Nuclear Information System (INIS)

Dose calculations for radiation arc therapy are traditionally performed by approximating continuous delivery arcs with multiple static beams. For 3D conformal arc treatments, the shape and weight variation per degree is usually small enough to allow arcs to be approximated by static beams separated by 5"0-10"0. But with intensity-modulated arc therapy (IMAT), the variation in shape and dose per degree can be large enough to require a finer angular spacing. With the increase in the number of beams, a deterministic dose calculation method, such as collapsed-cone convolution/superposition, will require proportionally longer computational times, which may not be practical clinically. We propose to use a homegrown Monte Carlo kernel-superposition technique (MCKS) to compute doses for rotational delivery. The IMAT plans were generated with 36 static beams, which were subsequently interpolated into finer angular intervals for dose calculation to mimic the continuous arc ...

2008-09-07

443

Spectral properties of cylindrical quasioptical cavity resonator with random inhomogeneous side boundary.  

Science.gov (United States)

A rigorous solution for the spectrum of a quasioptical cylindrical cavity resonator with a randomly rough side boundary has been obtained. To accomplish this task, we have developed a method for the separation of variables in a wave equation, which enables one, in principle, to rigorously examine any limiting case-from negligibly weak to arbitrarily strong disorder at the resonator boundary. It is shown that the effect of disorder-induced scattering can be properly described in terms of two geometric potentials, specifically, the "amplitude" and the "gradient" potentials, which appear in wave equations in the course of conformal smoothing of the resonator boundaries. The scattering resulting from the gradient potential appears to be dominant, and its impact on the whole spectrum is governed by the unique sharpness parameter ?, the mean tangent of the asperity slope. As opposed to the resonator with bulk disorder, the distribution of nearest-neighbor spacings (NNS) ...

2011-08-30

444

Simulation for position determination of distal and proximal edges for SOBP irradiation in hadron therapy by using the maximum likelihood estimation method  

Energy Technology Data Exchange (ETDEWEB)

In radiation therapy with hadron beams, conformal irradiation to a tumour can be achieved by using the properties of incident ions such as the high dose concentration around the Bragg peak. For the effective utilization of such properties, it is necessary to evaluate the volume irradiated with hadron beams and the deposited dose distribution in a patient's body. Several methods have been proposed for this purpose, one of which uses the positron emitters generated through fragmentation reactions between incident ions and target nuclei. In the previous paper, we showed that the maximum likelihood estimation (MLE) method could be applicable to the estimation of beam end-point from the measured positron emitting activity distribution for mono-energetic beam irradiations. In a practical treatment, a spread-out Bragg peak (SOBP) beam is used to achieve a uniform biological dose distribution in the whole target volume. Therefore, in the present paper, we proposed ...

2005-12-21

445

Search for the active components and studies on the mechanism of the hematopoiesis improvement foods  

Energy Technology Data Exchange (ETDEWEB)

In this experiments, we established long-termed culture methods of bone marrow stromal cells for proliferation and differentiation of stem cells. And we selected some extracts which support maximal proliferation of stromal cells with this method. We conformed the synergic effects of herval mixture extracts for stromal cell growth. The proliferation of stromal cells was increased rather by the addition of mixture extracts than by addition of single strain extract. In the previous and cooperative experiments, we selected complex extracts which increased the number of nonadherent mononuclear cells. Different cytokine expression patterns were observed stromal cells cultured in the presence or absence of mixture extracts which support differentiation of nonadherent cells. Stimulation of macrophage cell line with herval extracts with the treatments of recombinant interferon-{gamma} resulted in increased nitric oxide synthesis in a dose-dependent manners. In addition, ...

1999-04-01

446

Routine environmental audit of the Y-12 Plant, Oak Ridge, Tennessee  

Energy Technology Data Exchange (ETDEWEB)

This report documents the results of the routine environmental audit of the Oak Ridge Y-12 Plant (Y-12 Plant), Anderson County, Tennessee. During this audit, the activities conducted by the audit team included reviews of internal documents and reports from previous audits and assessments; interviews with U.S. Department of Energy (DOE), State of Tennessee regulatory, and contractor personnel; and inspections and observations of selected facilities and operations. The onsite portion of the audit was conducted August 22-September 2, 1994, by the DOE Office of Environmental Audit (EH-24), located within the Office of Environment, Safety and Health (EH). DOE 5482.1 B, {open_quotes}Environment, Safety, and Health Appraisal Program,{close_quotes} establishes the mission of EH-24 to provide comprehensive, independent oversight of DOE environmental programs on behalf of the Secretary of Energy. The ultimate goal of EH-24 is enhancement of environmental protection and minimization of risk to ...

1994-09-01

447

Reduction of RF-sheaths potentials by compensation or suppression of parallel RF currents on ICRF antennas  

International Nuclear Information System (INIS)

Radio frequency (RF) sheaths are suspected of limiting the performance of present-day ion cyclotron range of frequencies (ICRFs) antennas over long pulses and should be minimized in future fusion devices. Within the simplest models, RF-sheath effects are quantified by the integral VRF = ? E|| ? dl where the parallel RF field E|| is linked with the slow wave. On 'long open field lines' with large toroidal extension on both sides of the antenna it was shown that VRF is excited by parallel RF currents j|| flowing on the antenna structure. In this paper, the validity of this simple sheath theory is tested experimentally on the Tore Supra (TS) ITER-like antenna prototype (ILP), together with antenna simulation and post-processing codes developed to compute VRF. The predicted poloidal localization of high-|VRF| zones is confronted to that inferred from experimental data analysis. Surface temperature distribution on ILP front face, as well as ILP-induced modifications of RF coupling and hot ...

2010-02-01

448

Quantum-chemical simulation of 1H NMR spectra. 2. Comparison of DFT-based procedures for computing proton-proton coupling constants in organic molecules.  

Science.gov (United States)

The performance of 250 different computational protocols (combinations of density functionals, basis sets and methods) was assessed on a set of 165 well-established experimental (1)H-(1)H nuclear coupling constants (J(H-H)) from 65 molecules spanning a wide range of "chemical space". Thereby we found that, if one uses core-augmented basis sets and allows for linear scaling of the raw results, calculations of only the Fermi contact term yield more accurate predictions than calculations where all four terms that contribute to J(H-H) are evaluated. It turns out that B3LYP/6-31G(d,p)u+1s is the best (and, in addition, one of the most economical) of all tested methods, yielding predictions of J(H-H) with a root-mean-square deviation from experiment of less than 0.5 Hz for our test set. Another method that does similarly well, without the need for additional 1s basis functions, is B3LYP/cc-pVTZ, which is, however, ca. 8 times more "expensive" in terms of CPU time. A selection of the better ...

2011-05-16

449

Prospects and future of conservative management of beta thalassemia major in a developing country  

International Nuclear Information System (INIS)

Objective: To assess the efficacy, prospects and future of conservative management of beta thalassemia major patients in a developing country. Design: Patients registered at IHBTS were studied over a period of three years. They consented to being managed on moderate transfusion regimen, aiming to maintain a pre-transfusion haemoglobin(Hgb) level of 9.0 plus minus 1.0 g per dL. We studied their transfusion requirements, status for transfusion transmitted infections (TTls), serum ferritin levels and complications developing as a result of iron overload. Subjects: Initially all registered patients were included in this study. Sporadic patients as well as dropouts occurring due to any reason, (patients concurrently seeking treatment at other centres as well, or complying poorly to advised chelation therapy) were excluded from the study. The data presented here conforms to a cohort of 60 regular patients who adhered best to our selection criteria. Main Outcome Measures: ...

2004-01-01

450

Presentation of Type B Peptide-MHC Complexes from Hen Egg White Lysozyme by TLR Ligands and Type I IFNs Independent of H2-DM Regulation.  

Science.gov (United States)

In APCs, presentation by MHC II molecules of the chemically dominant peptide from the protein hen egg white lysozyme (HEL) generates different conformational isomers of the peptide-MHC II complexes (pMHC). Type B pMHCs are formed in early endosomes from exogenous peptides in the absence of H2-DM, whereas in contrast, type A pMHC complexes are formed from HEL protein in late vesicles after editing by H2-DM. Thus, H2-DM edits off the more unstable pMHC complexes, which are not presented from HEL. In this study, we show that type B pMHC complexes were presented from HEL protein only after stimulation of dendritic cells (DC) with TLR ligands or type I IFN. Type I IFN contributed to most TLR ligand-induced type B pMHC generation, as presentation decreased in DC lacking the receptor for type I IFNs (IFNAR1(-/-)). In contrast, presentation of type A pMHC from HEL and from peptide was minimally affected by TLR ligands. The relative effectiveness of CD8?(+) DC or CD8?(-) DC ...

2011-07-25

451

Phase I Study of Conformal Radiotherapy and Concurrent Full-Dose Gemcitabine with Erlotinib for Unresected Pancreatic Cancer.  

Science.gov (United States)

PURPOSE: To determine the recommended dose of radiotherapy when combined with full-dose gemcitabine and erlotinib for unresected pancreas cancer. METHODS AND MATERIALS: Patients with unresected pancreatic cancer (Zubrod performance status 0-2) were eligible for the present study. Gemcitabine was given weekly for 7 weeks (1,000 mg/m(2)) with erlotinib daily for 8 weeks (100 mg). A final toxicity assessment was performed in Week 9. Radiotherapy (starting at 30 Gy in 2-Gy fractions, 5 d/wk) was given to the gross tumor plus a 1-cm margin starting with the first dose of gemcitabine. A standard 3 plus 3 dose escalation (an additional 4 Gy within 2 days for each dose level) was used, except for the starting dose level, which was scheduled to contain 6 patients. In general, Grade 3 or greater gastrointestinal toxicity was considered a dose-limiting toxicity, except for Grade 3 anorexia or Grade 3 fatigue alone. RESULTS: A total of 20 patients were treated (10 men and 10 women). Nausea, ...

2011-05-01

452

Performance test of a small compact combined heating and electricity generating plant; Erfolgskontrolle Klein-Blockheizkraftwerk  

Energy Technology Data Exchange (ETDEWEB)

The present project examined the operating characteristics and application possibilities of a new, compact combined heating and electricity generating unit with a thermal output of 14,5 kW and a generating capacity of 5,5 kW. Such a module was installed in a plant in Arlesheim (Canton of Basel-Country) and subject to performance measurements. The small heating and generating plant is designed for cyclic operation (without heat storage) and is very compact and low in cost. The heating and generating unit conforms to all Swiss regulations relating to electrical installations and air pollution control. The NO{sub x} emissions of the unit (400 mg/m{sup 3} in steady state operation) are above the limits of LRV 92 (80 mg/m{sup 3}), but the regulation does not apply for units in this power range. The electricity generation costs are approximately CHF 0.16/kWh. It therefore makes sense to install the module in regions with average supply tariffs of at least CHF 0.16/kWh. ...

1995-12-01

453

Nuclear magnetic resonance spectroscopy in biomedicine. Course organized by the Istituto Superiore di Sanita`. Marciana Marina (Isola d`Elba), September 18-23, 1995; Spettroscopia di risonanza magnetica nucleare in biomedicina. Corso organizzato dall`Istituto Superiore di Sanita`. Marciana Marina (Isola d`Elba), 18-23 settembre 1995  

Energy Technology Data Exchange (ETDEWEB)

Nuclear magnetic resonance is a powerful technique that can be used in a wide range of applications, such as the structural characterization of high molecular weight molecules, conformational studies on enzymes in solution, enzyme-substrate or DNA-protein interactions, monitoring of cell metabolism in vivo, and for diagnostic purposes, employing spectroscopic and imaging techniques. This course was organized in order to introduce the participants to the fundamentals of NMR spectroscopy, and offer practical advice on performing NMR experiments on cell systems, cell and tissue extracts and animal models. The main implications regarding human experiments were also discussed. Finally the quantification of information and the interpretation of data were considered with regard to the main nuclei observed. [Italiano] La risonanza magnetica nucleare e` una delle tecniche spettroscopiche che meglio risponde all`ampio spettro di condizioni imposto dalla ricerca in biofisica ...

1997-12-01

454

New technetium-99m radiopharmaceuticals for brain imaging  

International Nuclear Information System (INIS)

Radiopharmaceuticals for brain imaging are used for the detection of ischemia, tumours and dementia associatied with disorders of the blood flow in the brain. The current radiopharmaceuticals for brain imaging have various limitations: 2-(F-18)fluoro-2-deoxyglucose (F-18-FDG) has a very short half-life. The physical properties of di-#beta#-(piperidinoethyl)-(Se-75)selenide (Se-75-PIPSE) and di-#beta#-(morpholinoethyl)-(Se-75)-selenide (Se-75-MOSE) are not ideal. Thallium-201 diethyldithricarbamate (T1-201-DDC) has unfavourable nuclidic characteristics, limited availability, a long half-life and high cost. I-123 in N-isopropyl-p-iodoamphetamine (I-123-IMP) and N,N,N'-trimethyl-N'-(2-hydroxy-3-methyl-5-iodobenzyl)-1,3-propanediamine (I-123-HIPDM) are not freely available and are expensive. N-13-labelled ammonia has a very short half-life. Technetium-99m hexamethylpropyleneamineoxime (Tc-99m-HM-PAO) is unstable both in vitro and in vivo and has a low brain-to-blood ratio. These ...

1988-08-01

455

Nanocrystal Bioassembly: Asymmetry, Proximity, and Enzymatic Manipulation  

Energy Technology Data Exchange (ETDEWEB)

Research at the interface between biomolecules and inorganic nanocrystals has resulted in a great number of new discoveries. In part this arises from the synergistic duality of the system: biomolecules may act as self-assembly agents for organizing inorganic nanocrystals into functional materials; alternatively, nanocrystals may act as microscopic or spectroscopic labels for elucidating the behavior of complex biomolecular systems. However, success in either of these functions relies heavily uponthe ability to control the conjugation and assembly processes.In the work presented here, we first design a branched DNA scaffold which allows hybridization of DNA-nanocrystal monoconjugates to form discrete assemblies. Importantly, the asymmetry of the branched scaffold allows the formation of asymmetric2assemblies of nanocrystals. In the context of a self-assembled device, this can be considered a step toward the ability to engineer functionally distinct inputs and outputs.Next we develop an ...

2008-05-01

456

Monte Carlo simulation of electron cones used in electron beam therapy  

International Nuclear Information System (INIS)

A Siemens Mevatron KV2 accelerator installed at the Royal Adelaide Hospital employs cylindrical solid-walled electron cones for some electron collimation. The cones being used at present result in treatment fields that do not always conform with the International Electrotechnical Commission (IEC) Standards (particularly at high energies). The aim of this project was to simulate the existing cones using Monte Carlo methods in order to evaluate potential cone modifications required to overcome the field irregularities. Simulations were performed using the EGS4 (Electron Gamma Shower version 4, distribution II) Monte Carlo code installed on a DEC Alpha workstation at the University of South Australia. To rigorously simulate the existing electron cones it was necessary to also simulate various components within the treatment head of the linear accelerator. Results of simulations for existing cones were found to be consistent with experimental data. (obtained from Royal ...

1998-09-01

457

Insulin-like growth factor II receptor is phosphorylated by a tyrosine kinase in adipocyte plasma membranes  

Energy Technology Data Exchange (ETDEWEB)

Incorporation of /sup 32/P from (gamma-32P)ATP into tyrosine residues of the insulin-like growth factor (IGF)-II receptor was observed in a Triton X-100-insoluble fraction of rat adipocyte plasma membranes. IGF-II receptor phosphorylation proceeded to a stoichiometry of approximately 0.5 mol of phosphate/IGF-II binding site after 10 min of incubation at 4 degrees C. A Km for ATP of 6 microM was calculated for this phosphorylation reaction. Addition of IGF-II caused an approximately 2-fold increase in tyrosine phosphorylation of the IGF-II receptor in this preparation. In contrast, phosphorylation of angiotensin II by the Triton X-100 washed membranes was not stimulated by IGF-II. Incubation of purified receptor immobilized on IGF-II agarose or of receptor-enriched low density microsomal membranes with (gamma-32P)ATP did not result in appreciable incorporation of (/sup 32/P)phosphate into the IGF-II receptor nor into exogenous substrates. These data suggest that the IGF-II receptor is ...

1986-06-15

458

Highly corrosion-resistant Cu_7_0(Ni,Fe,Mn,Cr)_3_0 cupronickel designed using a cluster model for stable solid solutions  

International Nuclear Information System (INIS)

Minor M (M = Fe, Mn, Cr) additions are widely added to enhance the corrosion resistance of commercial cupronickel alloys. The present paper aims at optimizing the amounts of M in Cu_7_0(Ni,Fe,Mn,Cr)_3_0 (at.%) alloys using a cluster-plus-glue-atom model for stable solid solutions. By this model, it assumed that 1 M atom and 12 Ni atoms formed an M-centered and Ni-surrounded cube-octahedron cluster and the isolated M_1Ni_1_2 clusters are embedded in a Cu matrix, conforming to a cluster formula [M_1Ni_1_2]Cu_3_0_._3 = [M_1_/_1_3Ni_1_2_/_1_3]_3_0Cu_7_0. A structure of this kind satisfies ideally the nearest neighbor requirement, i.e. only M-Ni and Ni-Cu neighbors are allowed and the unfavorable Cu-M pairs are avoided, and hence it describes a stable solid solution structure with good thermal stability. Electrochemical corrosion measurements indicated that [(Fe_0_._6Mn_0_._2_5Cr_0_._1_5)_1Ni_1_2]Cu_3_0_._3 had the best corrosion resistance in 3.5% NaCl aqueous ...

2010-08-27

459

Genus 4 trigonal reduction of the Benney equations  

International Nuclear Information System (INIS)

It was shown by Gibbons and Tsarev (1996 Phys. Lett. A 211 19, 1999 Phys. Lett. A 258 263) that N-parameter reductions of the Benney equations correspond to particular N-parameter families of conformal maps. In recent papers (Baldwin and Gibbons 2003 J. Phys. A: Math. Gen. 36 8393-417, Baldwin and Gibbons 2004 J. Phys. A: Math. Gen. 37 5341-54), the present authors have constructed examples of such reductions where the mappings take the upper half p-plane to a polygonal slit domain in the #lambda#-plane. In those cases, the mapping function was expressed in terms of the derivatives of Kleinian #sigma# functions of hyperelliptic curves, restricted to the one-dimensional stratum #THETA#_1 of the #THETA#-divisor. This was done using an extension of the method given in Enolskii et al (2003 J. Nonlinear Sci. 13 157) extended to a genus 3 curve (Enolski V Z and Gibbons J Addition theorems on the strata of the theta divisor of genus three hyperelliptic curves, in ...

2006-04-07

460

Formation of silk fibroin nanoparticles in water-miscible organic solvent and their characterization  

Energy Technology Data Exchange (ETDEWEB)

When Silk fibre derived from Bombyx mori, a native biopolymer, was dissolved in highly concentrated neutral salts such as CaCl{sub 2}, the regenerated liquid silk, a gradually degraded peptide mixture of silk fibroin, could be obtained. The silk fibroin nanoparticles were prepared rapidly from the liquid silk by using water-miscible protonic and polar aprotonic organic solvents. The nanoparticles are insoluble but well dispersed and stable in aqueous solution and are globular particles with a range of 35-125 nm in diameter by means of TEM, SEM, AFM and laser sizer. Over one half of the {epsilon}-amino groups exist around the protein nanoparticles by using a trinitrobenzenesulfonic acid (TNBS) method. Raman spectra shows the tyrosine residues on the surface of the globules are more exposed than those on native silk fibers. The crystalline polymorph and conformation transition of the silk nanoparticles from random-coil and {alpha}-helix form (Silk I) into ...

2007-10-15

461

Fiscal 1993 report on results of R and D on innovative technology for producing advanced biomaterial. Peptide applied carbon dioxide fixation/effective utilization technology (First volume); 1993 nendo senshin bio zairyo no sosei kako gijutsu no kenkyu kaihatsu seika hokokusho. 1. Peptide oyo nisanka tanso koteika yuko riyo gijutsu  

Energy Technology Data Exchange (ETDEWEB)

Technology is being developed for preparing functional materials by synthesizing new functional peptides in which non-natural amino acid needed for the functional manifestation is introduced, and by modifying the surface of a base plate such as silica glass by using such peptides. Activities were conducted in the three areas of (1) creation of functional molecules, (2) materialization technology, and (3) comprehensive investigation and research; the activities were carried out independently and parallelly in the first two areas. In (1), design technique for the structures and functions of peptides was developed, as were conformational control technique, synthesis of peptides having optical/electronic functions, peptide synthesis by an enzyme method, and R and D on introduction of non-natural amino acid into peptides; in (2), element technologies were developed such as substrate forming technique (pattern forming and thin film forming technology), substrate ...

1994-03-01

462

Exploring the structural dynamics of the E. coli chaperonin GroEL using translation-libration-screw crystallographic refinement of intermediate states  

Energy Technology Data Exchange (ETDEWEB)

Large rigid-body domain movements are critical to GroEL-mediated protein folding, especially apical domain elevation and twist associated with the formation of a folding chamber upon binding ATP and co-chaperonin GroES. Here, we have modeled the anisotropic displacements of GroEL domains from various crystallized states, unliganded GroEL, ATP?S-bound, ADP-AlFx/GroES-bound, and ADP/GroES bound, using translation-libration-screw (TLS) analysis. Remarkably, the TLS results show that the inherent motions of unliganded GroEL, a polypeptide-accepting state, are biased along the transition pathway that leads to the folding-active state. In the ADP-AlFx/GroES-bound folding-active state the dynamic modes of the apical domains become reoriented and coupled to the motions of bound GroES. The ADP/GroES complex exhibits these same motions, but they are increased in magnitude, potentially reflecting the decreased stability of the complex after nucleotide hydrolysis. Our results have allowed the ...

2004-08-12

463

Effect of Collimation Slit and Shield Thickness in a Prompt Gamma-based Proton Beam Range Measurement System  

Energy Technology Data Exchange (ETDEWEB)

The proton beam has a unique advantage over the electron and photon beams in that it can give very high radiation dose to the tumor volume, while effectively sparing the neighboring healthy tissue and organs. For the clinical application of the proton beam, it is very important to confirm the location of the proton beam in the patient, preferentially during the treatment. It has been suggested that the range of the proton beam in the patient can be determined by measuring prompt gammas from the proton beam passage. Recently, a prototype prompt-gamma scanning system has been constructed and tested using experimental and therapeutic proton beams. The measurement results for the proton beams of 70 . 230 MeV showed that a clear correlation exists between the distribution of the prompt gammas and the proton beam range. The scanning method, however, is not suitable for the upcoming 'spot scanning' technique. The 'spot scanning' technique provides ...

2007-07-01

464

Development of functional foods for radiation workers - Search for the active components and studies on the mechanism of the hematopoiesis improvement foods  

Energy Technology Data Exchange (ETDEWEB)

In this experiments, we established long-termed culture methods of bone marrow stromal cells for proliferation and differentiation of stem cells. And we selected some extracts which support maximal proliferation of stromal cells with this method. We conformed the synergic effects of herbal mixture extracts for stromal cell growth. The proliferation of stromal cells was increased rather by the addition of mixture extracts than by addition of single strain extract. In the previous and cooperative experiments, we selected complex extracts (Him-I, Him-II) which increased the number of nonadherent mononuclear cells. Different cytokine expression patterns were observed stromal cells cultured in the presence or absence of mixture extracts which support differentiation of nonadherent cells. Some fractions of Him-I and Him-II increased the proliferation of bone marrow cells irradiated {gamma}-ray(4Gray). Stimulation of macrophage cell line with herval extracts with the ...

2000-04-01

465

Cosmologies with quasiregular singularities. II. Stability considerations  

Energy Technology Data Exchange (ETDEWEB)

The stability properties of a class of spacetimes with quasiregular singularities is discussed. Quasiregular singularities are the end points of incomplete, inextendible geodesics at which the Riemann tensor and its derivatives remain at least bounded in all parallel-propagated orthonormal (PPON) frames; observers approaching such a singularity would find that their world lines come to an end in a finite proper time. The Taub-NUT (Newman-Unti-Tamburino)-type cosmologies investigated are R/sup 1/ x T/sup 3/ and R/sup 3/ x S/sup 1/ flat Kasner spacetimes, the two-parameter family of spatially homogeneous but anisotropic Bianchi type-IX Taub-NUT spacetimes, and an infinite-dimensional family of Einstein-Rosen-Gowdy spacetimes studied by Moncrief. The behavior of matter near the quasiregular singularity in each of these spacetimes is explored through an examination of the behavior of the stress-energy tensors and scalars for conformally coupled and minimally coupled, ...

1985-03-15

466

Cosmologies with quasiregular singularities. II. Stability considerations  

International Nuclear Information System (INIS)

The stability properties of a class of spacetimes with quasiregular singularities is discussed. Quasiregular singularities are the end points of incomplete, inextendible geodesics at which the Riemann tensor and its derivatives remain at least bounded in all parallel-propagated orthonormal (PPON) frames; observers approaching such a singularity would find that their world lines come to an end in a finite proper time. The Taub-NUT (Newman-Unti-Tamburino)-type cosmologies investigated are R"1 x T"3 and R"3 x S"1 flat Kasner spacetimes, the two-parameter family of spatially homogeneous but anisotropic Bianchi type-IX Taub-NUT spacetimes, and an infinite-dimensional family of Einstein-Rosen-Gowdy spacetimes studied by Moncrief. The behavior of matter near the quasiregular singularity in each of these spacetimes is explored through an examination of the behavior of the stress-energy tensors and scalars for conformally coupled and minimally coupled, massive and massless ...

467

Corrosion of stainless steels in 20 to 75% nitric acid. Final report. Korrosion von Chrom-Nickel-(Molybdaen)-Staehlen in unterazeotroper und azeotroper Salpetersaeure. Schlussbericht  

Energy Technology Data Exchange (ETDEWEB)

A series of stainless austenitic and ferritic materials was exposed for 100 days to boiling nitric acid which contained no corrosion products; the corrosion rates and depths of the grain boundary attack were observed. - Provided the structure is precipitation-free, the following are suitable for long-term exposure; the austenitic steels X 2 CrNi 19 11, X 1 CrNi 25 21, X 1 CrNiMoN 25 22 2 and X 1 NiCrMoCu 31 27 4, the practically Mo-free and Cu-free development steel X 1 NiCr 31 27, and the highly Mo-alloyed variant X 1 NiCrMoCu 31 27 5. - In the case of alloy NiCr21Mo it is advisable to limit the concentration and/or temperature of the nitric acid. - The 'superferrite' X 1 CrNiMoNb 28 4 2, the Japanese steel X 1 CrNiNb 30 2 and the austenitic steels X 2 CrNiMoN 17 13 3 and X 1 CrNiMoN 25 22 2 in the version with high nickel content are unsuitable. The decisive factor affecting the surface-removal rates is the chromium content of the material. The temperature-dependent ...

1988-01-01

468

An ultraviolet-inducible adenosine-adenosine cross-link reflects the catalytic structure of the Tetrahymena ribozyme  

Energy Technology Data Exchange (ETDEWEB)

When a shortened enzymatic version of the Tetrahymena self-splicing intervening sequence (IVS) RNA is placed under catalytic conditions and irradiated at 254 nm, a covalent cross-link forms with high efficiency. The position of the cross-link was mapped by using three independent methods: RNase H digestion, primer extension with reverse transcriptase, and partial hydrolysis of end-labeled RNA. The cross-link is chemically unusual in that it joins two adenosines, A57 and A95. Formation of this cross-link depends upon the identity and concentration of divalent cations present and upon heat-cool renaturation of the IVS in a manner that parallels conditions required for optimal catalytic activity. Furthermore, cross-linking requires the presence of sequences within the core structure, which is conserved among group I intervening sequences and necessary for catalytic activity. Together these correlations suggest that a common folded structure permits cross-linking and catalytic activity. ...

1990-06-12

469

Amplification of Inaccuracies of Initial Conditions in Cosmological Simulations  

Science.gov (United States)

Cosmological N-body and hydrodynamic simulations start with a realization of a random density fluctuation field representing a cosmological model at an early epoch. The density field is often replaced by a set of particles whose positions and velocities are set to conform to the desired density field. Each particle represents a cloud of huge number of real particles. Positions and velocities of particles are subsequently integrated by various numerical codes. We have simulated a set of collisionless collapses of Gaussian density peaks by using the PM and P(3) M codes. We find that in cosmological simulations the physics at scales below the mean particle separation(MPS) is dominated by inaccuracies in describing the initial density field, and cannot be studied even by the high force-resolution codes. Since density fluctuations are ill-defined at scales smaller than MPS, it is desirable not to amplify this problem during the evolution. The P(3) M code is shown to ...

1997-01-01

470

AECL IMPELA electron beam industrial irradiators  

International Nuclear Information System (INIS)

A family of industrial irradiators is being developed by AECL to cover an electron-beam energy range from 5 to 18 MeV at beam powers between 20 and 250 kW. The IMPELA family of irradiators is designed for push button, reliable operation. The major irradiator components are modular, allowing for later upgrades to meet increased demands in either electron or X-ray mode. Interface between the control system, irradiator availability and dose quality assurance is in conformance with the most demanding specifications. The IMPELA irradiators use a klystron-driven, standing-wave, L-band accelerator structure with direct injection from a rugged, triode electron gun. Direct control of the accelerating field during the beam pulse ensures constant output beam energy, independent of beam power. The first member of the family, the IMPELA 10/50 (10 MeV, 50 kW), is in the final stages of assembly at Chalk River Nuclear Laboratories. The IMPELA 10/50 is constructed around a 3.25 m ...

471

"1H and "3"1P nuclear magnetic resonance investigation of the interaction between 2,3-diphosphoglycerate and human normal adult hemoglobin  

International Nuclear Information System (INIS)

High-resolution "1H and "3"1P nuclear magnetic resonance spectroscopy has been used to investigate the binding of 2,3-diphosphoglycerate to human normal adult hemoglobin and the molecular interactions involved in the allosteric effect of the 2,3-diphosphoglycerate molecule on hemoglobin. Individual hydrogen ion NMR titration curves have been obtained for 22-26 histidyl residues of hemoglobin and for each phosphate group of 2,3-diphosphoglycerate with hemoglobin in both the deoxy and carbonmonoxy forms. The results indicate that 2,3-diphosphoglycerate binds to deoxyhemoglobin at the central cavity between the two #beta# chains and the binding involves the #beta#2-histidyl residues. Moreover, the results suggest that the binding site of 2,3-diphosphoglycerate to carbonmonoxyhemoglobin contains the same (or at least some of the same) amino acid residues responsible for binding in the deoxy form. As a result of the specific interactions with 2,3-diphosphoglycerate, the #beta#2-histidyl ...

472

Use of the parmbsc0 force field and trajectory analysis to study the binding of netropsin to the DNA fragment (5'CCAATTGG)2 in the presence of excess NaCl salt in aqueous solution  

British Library Electronic Table of Contents (United Kingdom)

The parmbsc0 force field was applied to study in detail the binding of netropsin, at a salt concentration of 0.28M Na^+, to the minor groove of an 8-mer (5'CCAATTGG)2 DNA duplex forming a netropsin.DNA complex which previously has been characterized by X-ray crystallography, albeit with the use of closely related DNA duplexes. The X-ray structure revealed that the terminal guanidinium and amidinium groups of netropsin interact with the extreme ends of the palindromic AATT sequence of the receptor DNA. The parmbsc0 parameters of B-DNA and AMBER v9 parameters of netropsin generated a stable 6ns molecular dynamics (MD) trajectory for a 1:1 class I binding motif of this complex. Trajectory analysis for the salt and hydration effects on the binding of netropsin to the 8-mer DNA duplex revealed ...

2011-01-01

473

Toward a Conceptual Refinement of Interpersonal Communication Competence: An Analysis of Subjects' Conceptions of Adept and Inept Communicators.  

Science.gov (United States)

A study examined the concept of interpersonal communication competence in order to construct a more refined instrument than those currently used to measure competence. Using 70 items drawn from several existing measures of competence, 660 volunteer subjects from undergraduate communication courses at a large midwestern university provided their conception of adept and inept communicators, defined respectively as the best and worst communicators they know. Direct and multiple step-wise discriminant analyses were performed to determine the extent to which these items best discriminated between subjects' conceptions of adept and inept communicators, and to determine which of the 70 items best discriminated between these conceptions. Canonical discriminant functions revealed that the subjects clearly distinguished between adept and inept communicators. Classification results revealed that nearly 97% of the cases were classified correctly. Results ...

1989-05-01

474

Thermal effect on superhydrophobic performance of stearic acid modified ZnO nanotowers  

Energy Technology Data Exchange (ETDEWEB)

The thermal desorption of stearic acid on superhydrophobic zinc oxide nanotowers has been investigated. The stearic acid passivated zinc oxide nanotowers provide a very high contact angle of {approx}173 {+-} 1.1 deg. with a very low hysteresis of {approx}1.4 {+-} 0.5 deg. due to the presence of a binary structure composed of several nanosteps on each nanotower of height {approx}700 nm that eventually reduces the area of contact between the drop and the nanotowers and trapping more air as revealed by the field emission scanning electron microscopy images. The superhydrophobic performance of these nanotowers, however, declines following annealing at elevated temperatures. Fourier transform infrared spectra show a reduction in the intensity of stearic acid -CH{sub n} peaks at elevated temperatures revealing the cause of the decrease in contact angle and confirming the occurrence of thermal desorption at 184 deg. C. The corresponding activation ...

2008-02-28

475

The crystal structure Escherichia coli Spy.  

Science.gov (United States)

Escherichia coli spheroplast protein y (EcSpy) is a small periplasmic protein that is homologous with CpxP, an inhibitor of the extracytoplasmic stress response. Stress conditions such as spheroplast formation induce the expression of Spy via the Cpx or the Bae two-component systems in E. coli, though the function of Spy is unknown. Here, we report the crystal structure of EcSpy, which reveals a long kinked hairpin-like structure of four ?-helices that form an antiparallel dimer. The dimer contains a curved oval shape with a highly positively charged concave surface that may function as a ligand binding site. Sequence analysis reveals that Spy is highly conserved over the Enterobacteriaceae family. Notably, three conserved regions that contain identical residues and two LTxxQ motifs are placed at the horizontal end of the dimer structure, stabilizing the overall fold. CpxP also contains the conserved sequence motifs and has a predicted ...

2010-11-01

476

Semiconductor properties and protective role of passive films of iron base alloys  

Energy Technology Data Exchange (ETDEWEB)

Semiconductor properties of passive films formed on the Fe-18Cr alloy in a borate buffer solution (pH = 8.4) and 0.1 M H{sub 2}SO{sub 4} solution were examined using a photoelectrochemical spectroscopy and an electrochemical impedance spectroscopy. Photo current reveals two photo action spectra that derived from outer hydroxide and inner oxide layers. A typical n-type semiconductor behaviour is observed by both photo current and impedance for the passive films formed in the borate buffer solution. On the other hand, a negative photo current generated, the absolute value of which decreased as applied potential increased in the sulfuric acid solution. This indicates that the passive film behaves as a p-type semiconductor. However, Mott-Schottky plot revealed the typical n-type semiconductor property. It is concluded that the passive film on the Fe-18Cr alloy formed in the borate buffer solution is composed of both n-type outer hydroxide and inner ...

2007-01-15

477

Semiconductor properties and protective role of passive films of iron base alloys  

International Nuclear Information System (INIS)

Semiconductor properties of passive films formed on the Fe-18Cr alloy in a borate buffer solution (pH = 8.4) and 0.1 M H_2SO_4 solution were examined using a photoelectrochemical spectroscopy and an electrochemical impedance spectroscopy. Photo current reveals two photo action spectra that derived from outer hydroxide and inner oxide layers. A typical n-type semiconductor behaviour is observed by both photo current and impedance for the passive films formed in the borate buffer solution. On the other hand, a negative photo current generated, the absolute value of which decreased as applied potential increased in the sulfuric acid solution. This indicates that the passive film behaves as a p-type semiconductor. However, Mott-Schottky plot revealed the typical n-type semiconductor property. It is concluded that the passive film on the Fe-18Cr alloy formed in the borate buffer solution is composed of both n-type outer hydroxide and inner oxide ...

2007-01-01

478

Relation study of different properties for tertiary pulsed electrodeposited Ni-based nanocomposite with Al2O3/Y2O3/CNT nanopowders  

British Library Electronic Table of Contents (United Kingdom)

Electrodeposition of tertiary alumina/yttria/carbon nanotube (Al2O3/Y2O3/CNT) nanocomposite by using pulsed current has been studied in this investigation. Coating process has been performed on nickel sulphate bath and nanostructure of obtained compound layer is examined with high precision figure analysis of SEM nanographs. The effects of process variables, i.e., Y2O3 concentration, treatment time, frequency and duty cycle, have been experimentally studied. Statistical methods are used to achieve the minimum of corrosion rate and average size of nanoparticles. Finally the contribution percentage of different effective factors is revealed and confirmation run shows the validity of obtained results. Also it has been revealed that by changing the size of nanoparticles, corrosion properties o...

2011-01-01

479

Proximal cholangiocarcinoma. Prognostic factor and effectiveness of post operative radiotherapy  

International Nuclear Information System (INIS)

To define the prognostic factors after surgical resection and evaluate the effectiveness of Post Operative Radiotherapy (PORT) in cases with cholangiocarcinoma, 44 cases with proximal cholangiocarcinoma were examined. The mean observation period was 20.6 months, and the survival rates 1, 3 and 5 years after the resection were 79.9%, 59.8% and 39.3%, respectively. Univariate analysis revealed that the presence of lymph node metastasis and absence of PORT were significant poor prognostic factors. Multivariate analysis revealed that the absence of PORT was a significant poor prognostic factor. The survival rates for 1 and 3 years after the resection were 80.0% and 40.0% in the curable A/B and PORT (-) group, and 100% and 53.3% in curable C and PORT (+) group. There were no local reccurences in the pathologically classified hm2 and em2 patients who underwent PORT. Even when the surgical margin is positive for the carcinoma pathologically, it is ...

2000-10-01

480

Oxide growth on aluminium alloys in the presence of ammonium fluoborate  

Energy Technology Data Exchange (ETDEWEB)

The aim of this study as to determine the mechanisms involved in using ammonium fluoborate as a reducing atmosphere when preheating a high magnesium content aluminium alloy. Rutherford Backscattering (RBS) has been the major technique used in the analysis of samples, it revealed significant reduction in both the diffusion of magnesium to the surface and the calculated oxide thickness in the presence of NH{sub 4}BF{sub 4}. At temperatures above 500 deg C in air, SEM images revealed depressions and voids due to incipient melting at various stages, around the grain boundaries. Grain boundaries effectively acted as pipes aiding the diffusion of magnesium to the surface. These results have been verified through compositional analysis with both RBS and auger electron spectroscopy (AES). Results from NH{sub 4}BF{sub 4} atmosphere preheat conditions showed significant improvements. It was verified experimentally that above 500 deg C , AA5182 alloys ...

1996-12-31

481

On-site energy production from agricultural residues  

Energy Technology Data Exchange (ETDEWEB)

Tests with a 61 cm diameter fluidized-bed combustor revealed that raw cotton gin trash could be efficiently burned while satisfying Federal standards for particulate emissions. Certain chemicals within cotton gin trash zone can cause slagging or caking of ash and bed particles in the combustion zone. They can also corrode and accumulate on the heat recovery equipment. These problems are not considered insurmountable and methods of control are being studied. Raw cotton gin trash was also converted into a low Btu gas using fluidized-bed technology. Tests with a 30 cm diameter gasifier revealed that raw gin trash could be converted to a combustible gas, containing carbon monoxide and hydrogen. The heating value of the gas ranged from 3.65 to 5.29 MJ/m3 and about 50 percent of the heat value of the raw trash was converted to combustible gases. Economic analyses have shown that these techniques can be economically competitive with present fuels in ...

1980-03-01

482

Mid infrared observations of Van Maanen 2: no substellar companion.  

Energy Technology Data Exchange (ETDEWEB)

The results of a comprehensive infrared imaging search for the putative 0.06 M{sub {circle_dot}} astrometric companion to the 4.4 pc white dwarf van Mannen 2 are reported. Adaptive optics images acquired at 3.8 {micro}m reveal a diffraction limited core of 0.09 inch and no direct evidence of a secondary. Models predict that at 5 Gyr, a 50 M{sub J} brown dwarf would be only 1 magnitude fainter than van Maanen 2 at this wavelength and the astrometric analysis suggested a separation of 0.2 inch. In the case of a chance alignment along the line of sight, a 0.4 mag excess should be measured. An independent photometric observation at the same wavelength reveals no excess. In addition, there exist published ISO observations of van Maanen 2 at 6.8 {micro}m and 15.0 {micro}m which are consistent with photospheric flux of a 6750 K white dwarf. If recent brown dwarf models are correct, there is no substellar companion with T{sub eff} {approx}> 500 ...

2004-11-03

483

Microstructural characterization of Ti-6Al-4V metal chips by focused ion beam (FIB) and transmission electron microscopy (TEM)  

Energy Technology Data Exchange (ETDEWEB)

The microstructure of the secondary deformation zone (SDZ) near the cutting surface in metal chips of Ti-6Al-4V formed during machining was investigated using focused ion beam (FIB) specimen preparation and transmission electron microscopy (TEM) imaging. Use of the FIB allowed precise extraction of the specimen across this region to reveal its inhomogeneous microstructure resulting from the non-uniform distribution of strain, strain rate, and temperature generated during the cutting process. Initial imaging from conventional TEM foil preparation revealed microstructures ranging from heavily textured to regions of fine grains. Using FIB preparation, the transverse microstructure could be interpreted as fine grains near the cutting surface which transitioned to coarse grains toward the free surface. At the cutting surface a 10 nm thick recrystallized layer was observed capping a 20 nm thick amorphous layer.

2011-01-01

484

Microstructural aspects of the corrosion of Alloy 800  

Energy Technology Data Exchange (ETDEWEB)

Transmission electron microscopy studies on solution-annealed Alloy 800 revealed small (100-200 nm), spherical-shaped titanium carbide (face centered cubic structure) and large (200 nm-5 {mu}m), faceted titanium nitride (hexagonal structure) particles randomly distributed in the austenite matrix. The volume fraction of former particles was found to be greater than that of the latter. Corrosion studies of the alloy in acidic, chlorides and acidic chloride environments at room temperature indicated that the passivity of Alloy 800 was adversely affected by the addition Cl{sup -} ions. X-ray photoelectron spectroscopy revealed that the surface film formed on the alloy at the onset of passivity consisted of Cr{sup 3+} (as Cr{sub 2}O{sub 3}), without any Fe{sup 3+}/Fe{sup 2+} or Ni{sup 2+}. Scanning electron microscopy studies indicated initiation of pitting at large, faceted particles, not at small, spherical-shaped ones.

2004-12-01

485

Lipid domain formation modulates activities of snake venom phospholipase A(2) enzymes.  

Science.gov (United States)

The goal of the present study is to elucidate the effect of lipid domain formation on activities of Naja naja atra and Bungarus multicinctus phospholipase A(2) (PLA(2)) enzymes. Sphingomyelin inhibited enzymatic activity and membrane-damaging activity of PLA(2) against egg yolk phosphatidylcholine (EYPC), while cholesterol and cholesterol sulfate abrogated the inhibitory effect of sphingomyelin. The ability of cholesterol and cholesterol sulfate to abolish the inhibitory effect of sphingomyelin was closely related to their capacity to induce domain formation in EYPC/sphingomyelin vesicles. Laurdan fluorescence measurement revealed that membrane packing of EYPC/sphingomyelin vesicles was differently affected by cholesterol and cholesterol sulfate. Unlike cholesterol, cholesterol sulfate was unable to promote domain formation in dipalmitoylphosphatidylcholine (DPPC) vesicles. Cholesterol increased but cholesterol sulfate reduced PLA(2) activity against DPPC. ...

2010-08-10

486

Insertion Loss of Personal Protective Clothing  

Energy Technology Data Exchange (ETDEWEB)

'The use of personal protective clothing that covers the head is a common practice in many industries. Such personal protective clothing will impact the sound pressure level and the frequency content of sounds to which the wearer will be exposed. The use of such clothing, then, may impact speech and alarm audibility. A measure of the impact of such clothing is its insertion loss. Insertion loss measurements were performed on four types of personal protective clothing in use by Westinghouse Savannah River Company personnel which utilize cloth and plastic hood configurations to protect the head. All clothing configurations tested at least partially cover the ears. The measurements revealed that insertion loss of the items tested was notable at frequencies above 1000 Hz only and was a function of material stiffness and acoustic flanking paths to the ear. Further, an estimate of the clothing''s noise reduction rating ...

1999-05-13

487

Influence of the porous texture of coals on their hydrogenation processes catalyzed by Fe  

Energy Technology Data Exchange (ETDEWEB)

Nine coals from Spanish, British, German and American mining basins were hydrogenated using Fe catalyst precursors (red mud and FeSO{sub 4}), without solvent at 300, 350, and 400 {degree}C and 10 MPa of H{sub 2}. Overall conversion and product distribution are related to the textural characteristics of the original coals and are studies throughout the distinct hydrogenation processes. Results reveal that with FeSO{sub 4} as a catalyst precursor, conversions increase with coal surface area. However, when red mud (RM) is used, conversions are independent of coal textural characteristics. Higher conversions are obtained with FeSO{sub 4} than with RM at 300 and 350 {degree}C whereas at 400 {degree}C higher conversions are obtained with RM. This different catalytic activity is also reflected in the changes of the textural characteristics observed in each case. Up to 350 {degree}C, the residues from FeSO{sub 4}-catalyzed processes reveal increased ...

1995-03-01

488

Influence of temperature on corrosion behavior of PbCaSnCe alloy in 4.5 M H{sub 2}SO{sub 4} solution  

Energy Technology Data Exchange (ETDEWEB)

The temperature effect on corrosion behaviors of PbCaSnCe alloy in 4.5 M H{sub 2}SO{sub 4} solution was investigated by using potentiodynamic curve, electrochemical impedance spectra (EIS), Mott-Schottky plot and photocurrent response methods. It was found that PbCaSnCe alloy was in passive state in sulfuric acid solution, a passive film can be formed on alloy surface. The compositions of passive films formed at 0.9 V for 2 h under different temperatures were detected by X-ray photoelectron spectroscopy (XPS). The results showed that the film resistance and the transfer resistance decreased with the increment of the solution temperature. Mott-Schottky analysis and the photocurrent response revealed that the passive film exhibited n-type semi-conductive character, the donor density of the passive film decreased with increasing the solution temperature. Photocurrent response revealed that the photocurrent increased with increasing temperature. ...

2010-01-15

489

High resolution scanning electron microscopy of plasmodesmata.  

Science.gov (United States)

Symplastic transport occurs between neighbouring plant cells through functionally and structurally dynamic channels called plasmodesmata (PD). Relatively little is known about the composition of PD or the mechanisms that facilitate molecular transport into neighbouring cells. While transmission electron microscopy (TEM) provides 2-dimensional information about the structural components of PD, 3-dimensional information is difficult to extract from ultrathin sections. This study has exploited high-resolution scanning electron microscopy (HRSEM) to reveal the 3-dimensional morphology of PD in the cell walls of algae, ferns and higher plants. Varied patterns of PD were observed in the walls, ranging from uniformly distributed individual PD to discrete clusters. Occasionally the thick walls of the giant alga Chara were fractured, revealing the surface morphology of PD within. External structures such as spokes, spirals and mesh were observed ...

2011-05-28

490

Genetic engineering of group 2 sigma factor SigE widely activates expressions of sugar catabolic genes in Synechocystis species PCC 6803.  

Science.gov (United States)

Metabolic engineering of photosynthetic organisms is required for utilization of light energy and for reducing carbon emissions.Control of transcriptional regulators is a powerful approach for changing cellular dynamics, because a set of genes is concomitantly regulated. Here, we show that overexpression of a group 2 ? factor, SigE, enhances the expressions of sugar catabolic genes in the unicellular cyanobacterium, Synechocystis sp. PCC 6803. Transcriptome analysis revealed that genes for the oxidative pentose phosphate pathway and glycogen catabolism are induced by overproduction of SigE. Immunoblotting showed that protein levels of sugar catabolic enzymes, such as glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, glycogen phosphorylase, and isoamylase, are increased. Glycogen levels are reduced in the SigE-overexpressing strain grown under light. Metabolome analysis revealed that metabolite levels of the TCA cycle and ...

2011-07-11

491

From Sakata Model to Goldberg-Ne'eman Quarks and Nambu QCD Phenomenology and "Right" and "Wrong" experiments  

CERN Document Server

The basic theoretical milestones were the Sakata SU(3) symmetry, the Goldberg-Ne'eman composite model with SU(3) triplets having baryon number (1/3) and the Nambu color gauge Lagrangian. The transition was led in right and wrong directions by experiments interpreted by phenomenology. A "good" experiment on $\\bar p p$ annihilation at rest showed that the Sakata model predictions disagreed with experiment. A "bad" experiment prevented the use of the Goldberg-Ne'eman triplet model to predict the existence and masses of the of the $\\Xi^*$ and $\\Omega^-$. More "good" experiments revealed the existence and mass of the $\\Xi^*$ and the $\\Omega^-$ and the absence of positive strangeness baryon resonances, thus confirming the "tenfold way". Further "good experiments" revealed the existence of the vector meson nonet, SU(3) breaking with singlet-octet mixing and the suppression of the $\\phi \\to \\rho \\pi$ decay. These led to the quark triplet ...

2007-01-01

492

Electrochemical ozone production: influence of the supporting electrolyte on kinetics and current efficiency  

International Nuclear Information System (INIS)

The nature of the electrolyte strongly influences the electrode kinetics of the oxygen evolution reaction (OER) and electrochemical ozone production (EOP) mainly by affecting the degree of coverage by the intermediates of both processes. The anomalous behaviour of the Tafel coefficient, b, as a function of temperature was attributed to surface adsorption of the electrolyte species, and the competition between them, as well as gas bubble adherence. Comparison of the current efficiencies of the EOP, PHI_E_O_P, determined for different temperatures and supporting electrolyte compositions, showed the presence of fluorinated anions increases PHI_E_O_P. The influence of the anion nature on PHI_E_O_P, when analysed in the light of the proposed electrode mechanism, reveals introduction into the electrolyte of anions having a high electronegativity changes the double layer structure resulting in an increase of surface concentration of the active centres leading to EOP. The ...

2003-02-05

493

Effect of Temperature on the Local Structure of Kaolinite Intercalated with Potassium Acetate  

International Nuclear Information System (INIS)

Kaolinite intercalated with potassium acetate is of great interest in the areas of environmental remediation and industrial application; however, its exact atomic structure and the changes which occur when heated have remained largely elusive. Here, neutron pair distribution function analysis is used to investigate the local structural characteristics of this complex material, revealing that hydrated potassium acetate exists as a single layer in the interlamellar spacing of kaolinite. Furthermore, the potassium ions within the intercalated complex are most likely associated with the resonance structure of the acetate molecules, and upon heating (and decomposition of the carbon containing molecules), these ions become strongly associated with the negative charge located on the oxygen atoms in the alumina layers of dehydroxylated kaolinite. Several possible orientations of hydrated potassium acetate within the interlamellar spacing of kaolinite have been proposed and ...

2011-01-25

494

EPR and FT-IR spectroscopic studies of Bi2O3-B2O3-CuO glasses  

International Nuclear Information System (INIS)

EPR and FT-IR absorption measurements have been performed for xCuO.(100-x)[2Bi2O3.B2O3] glass system, with 0?x?50 mol%. The mode in which the addition of the copper ions influences the structure of 2Bi2O3.B2O3 glass matrix was analyzed. The EPR absorption spectra revealed the presence in the glass structure of Cu2+ ions in axially distorted octahedral environments. EPR data pointed out the simultaneous presence of Cu2+ and Cu+ ionic species in the glasses with x?5 mol%. For x>10 mol%, the Cu2+ ions participate in the superexchange magnetic interactions, which increase with CuO content. The FT-IR spectra showed the presence of some bands that are assigned to vibrations of Bi-O bonds from BiO3 pyramidal and BiO6 octahedral units and B-O bonds from BO3 and BO4 units. The data obtained by these measurements reveal the structural changes in the 2Bi2O3.B2O3 glass matrix by controlled doping of CuO.

2008-10-01

495

Biochemical and molecular genetic approaches on the radioprotective mechanism of natural products  

Energy Technology Data Exchange (ETDEWEB)

We reported the radio-protective effect of DTT. The treatment of DTT increased cell survival after gamma-irradiation, decreased in the frequencies of micronucleus, and reduction in DNA fragmentation and apoptotic cells. Induction of apoptosis after UV-C irradiation was revealed by the changes in the relative cell death, increase in the relative amount of apoptotic cells, and the induction of DNA fragmentation. About 100 medicinal plants were purchased and methanol extract samples were prepared. Radio-protective and radio-sensitizing activities of these samples were screened. Seven samples showed above 20% radio-protective activities: Salvia miltiorrhiza, Areca catechu, Cornus officinalis, Alpiniae officinari rhizoma, Meliae fructus, Alpiniae katsumadaii semen, Betulae cortex. Acanthopanax sessiliflous showed the highest radio-sensitizing effect and 10 other samples revealed moderate activities: Melia japonica, Agastache rugosa, Platycodon ...

1999-04-01

496

Assessment of the effects of pixel loss on image quality in direct digital radiography  

Energy Technology Data Exchange (ETDEWEB)

Modern digital radiographic 'flat panel' detectors can exhibit a progressive form of image degradation arising from non-functioning pixels. The effect of these 'dead pixels' on the quantitative image quality measures of modulation transfer function (MTF), noise power spectrum (NPS) and detective quantum efficiency (DQE) is investigated by a simulated degradation of images obtained from an Hologic EPEX system. The effects on the semi-quantitive measures obtained from contrast threshold test objects and resolution gratings are also investigated. Results suggest that the contrast-detail tests often employed in quality assurance measures are not sufficient to reveal the presence of dead pixels until well beyond the recommended replacement point for the flat panel detector. However, measurements of spatial resolution using a line pairs phantom were found to be more sensitive to pixel loss. Measurement of the MTF, NPS and DQE can ...

2004-03-21

497

Assessment of the effects of pixel loss on image quality in direct digital radiography  

International Nuclear Information System (INIS)

Modern digital radiographic 'flat panel' detectors can exhibit a progressive form of image degradation arising from non-functioning pixels. The effect of these 'dead pixels' on the quantitative image quality measures of modulation transfer function (MTF), noise power spectrum (NPS) and detective quantum efficiency (DQE) is investigated by a simulated degradation of images obtained from an Hologic EPEX system. The effects on the semi-quantitive measures obtained from contrast threshold test objects and resolution gratings are also investigated. Results suggest that the contrast-detail tests often employed in quality assurance measures are not sufficient to reveal the presence of dead pixels until well beyond the recommended replacement point for the flat panel detector. However, measurements of spatial resolution using a line pairs phantom were found to be more sensitive to pixel loss. Measurement of the MTF, NPS and DQE can reveal small changes ...

2004-03-21

498

An evaluation of low-dose single-slice helical CT in pulmonary CT scan  

International Nuclear Information System (INIS)

Objective: To investigate the feasibility of low-dose single-slice helical CT in pulmonary CT scan and evaluate the clinical application. Methods: Thirteen cases were selected out of 132 cases, in which low-dose (50mAs) single-slice helical CT scan of chest was performed. This set of cases included 7 cases of multiple metastatic nodules; 3 of solitary pulmonary, nodule; and 3 of pulmonary patchy lesions. Regular dose (170mAs) CT scan was also performed on all those patients. The regular dose and low dose CT scan were compared on sensitivity of detecting the lesions; the performance in demonstrating the details of the abnormalities; and the capability of revealing the segmental bronchi as well. Results: The same number and size of the pulmonary nodules were revealed with scan modalities loaded with different doses. No significant difference in demonstrating the details of the nodules and the segmental bronchi was found between both modalities ...

2006-04-01