WorldWideScience
1

The influence of EU policies on the evolution on coastal zones (Themati\\\\\\rc Study 'E')  

Wastenet

decline is due to EC measures introduced to control milk production (milk quotas, reduction in herd

2

Evolution of the primary components of massive binary stars in the case of Roche lobe overflow after main-sequence evolution  

International Nuclear Information System (INIS)

The components with masses 32 and 64M _s_u_n, evolved with the matter mixing in the semiconvective zone and filling their Roche lobes, after the main-sequence evolution overflow their Roche lobes and lose matter during the first part of the helium core burning. After the overflow end, the components lose the matter by stellar wind. The components shrink in the nuclear timescale. At first, they have the blue supergiant character with anomalous CNO abundance, then - the Wolf-Rayet stars character.

3

Integration of Microdialysis Sampling and Microchip Electrophoresis with Electrochemical Detection  

UK PubMed Central (United Kingdom)

Here we describe the fabrication, optimization, and application of a microfluidic device that integrates microdialysis (MD) sampling, microchip electrophoresis (ME), and electrochemical detection...Full Text Available

2008-12-01

4

The evolution of AGB stars with convective overshoot  

CERN Document Server

The influence of extended convective mixing (overshoot) on asymptotic giant branch stellar evolution is investigated in detail. The extended mixing is treated time-dependently, and the efficiency declines exponentially with the geometric distance from the convective boundary. It has been considered at all convective boundaries, including the He-flash convection zone in the intershell region which forms during the thermal pulses. Both the structural and the chemical evolution are affected by the inclusion of overshoot. The main results include a very efficient third dredge-up which leads to the formation of carbon stars of low mass and luminosity. A C13 pocket which may serve as a neutron source for the s-process can form after the third dredge-up has reached into the C12 rich intershell. Overshoot applied to the pulse-driven convective zone during the He-flash leads to a deeper penetration of the bottom ...

2000-01-01

6

Evolution of the triangle zone in the Rocky Mountains Foothills near Coalspur, Central Alberta  

Energy Technology Data Exchange (ETDEWEB)

A triangle zone, which commonly occurs along the external margin of a foreland thrust and fold belt with a buried thrust front, is underlain by a subhorizontal, blind, foreland-verging thrust that ends against a foreland-dipping, hinterland-verging thrust. These contemporaneous thrusts, active towards the end of orogenesis, enclose an intercutaneous wedge that moved towards the foreland. During orogenesis, a triangle zone evolves through periodic replacement of faults bounding the active wedge. Replacements occur in cycles during each of which a lower fault tends to be replaced by one in a lower stratigraphic horizon, an upper fault by one farther away from the foreland. Each cycle ends with the lower fault moving to a younger horizon where it joins a new, more external upper fault. Near Coalspur, the triangle zone exposes the remnants of several wedges involving Upper Cretaceous and Palaeocene molasse. Most of these wedges ...

1987-08-01

7

Six orders of magnitude dynamic range in capillary electrophoresis with ultrasensitive laser-induced fluorescence detection  

UK PubMed Central (United Kingdom)

An ultrasensitive laser-induced fluorescence detector was used with capillary electrophoresis for the study of 5-carboxy-tetramethylrhodamine. The raw signal from the detector provided roughly...Full Text Available

2009-12-15

8

Electrolytic Reduction: Modification of Proteins Occurring in Isoelectric Focusing Electrophoresis and in Electrolytic Reactions in the Presence of High Salts  

UK PubMed Central (United Kingdom)

Artifacts in two-dimensional electrophoresis (2-DE) caused by the presence of salts in isoelectric focusing (IEF) have been previously described as a result of increasing conductivity and inducing electroosmosis....Full Text Available

2009-05-15

9

Quick separation of fission product molybdenum and gamma-rays of Mo-102  

International Nuclear Information System (INIS)

... electrophoresis fission products gamma radiation gamma spectra half-life

10

The number and metallicities of the most metal-poor stars  

CERN Document Server

Simple, one-zone models for inhomogeneous chemical evolution of the Galactic halo are used to predict the number fraction of zero-metallicity, Population III stars, which currently is empirically estimated at < 4e-4. These analytic models minimize the number of free parameters, highlighting the most fundamental constraints on halo evolution. There are disagreements of at least an order of magnitude between observations and predictions in limiting cases for both homogeneous Simple Model and Simple Inhomogeneous Model (SIM). Hence, this demonstrates a quantitative, unambiguous discrepancy in the observed and expected fraction of Population III stars. We explore how the metallicity distribution of the parent enrichment events f(z_0) drives the SIM and predictions for the Population III fraction. The SIM shows that the previously-identified "high halo" and "low halo" populations are consistent with a continuous evolutionary ...

2003-01-01

11

The evolution of habitable zones during stellar lifetimes and its implications on the search for extraterrestrial life  

CERN Document Server

A stellar evolution computer model has been used to determine changes in the luminosity L and effective temperature T(e) of single stars during their time on the main sequence. The range of stellar masses investigated was from 0.5 to 1.5 times that of the Sun, each with a mass fraction of metals (metallicity, Z) from 0.008 to 0.05. The extent of each star's habitable zone (HZ) has been determined from its values of L and T(e). These stars form a reference framework for other main sequence stars. All of the 104 main sequence stars known to have one or more giant planets have been matched to their nearest stellar counterpart in the framework, in terms of mass and metallicity, hence closely approximating their HZ limits. The limits of HZ, for each of these stars, have been compared to its giant planet(s)'s range of strong gravitational influence. This allows a quick assessment as to whether Earth-mass planets could exist in stable orbits within ...

2003-01-01

12

Laser: a Tool for Optimization and Enhancement of Analytical Methods  

Energy Technology Data Exchange (ETDEWEB)

In this work, we use lasers to enhance possibilities of laser desorption methods and to optimize coating procedure for capillary electrophoresis (CE). We use several different instrumental arrangements to characterize matrix-assisted laser desorption (MALD) at atmospheric pressure and in vacuum. In imaging mode, 488-nm argon-ion laser beam is deflected by two acousto-optic deflectors to scan plumes desorbed at atmospheric pressure via absorption. All absorbing species, including neutral molecules, are monitored. Interesting features, e.g. differences between the initial plume and subsequent plumes desorbed from the same spot, or the formation of two plumes from one laser shot are observed. Total plume absorbance can be correlated with the acoustic signal generated by the desorption event. A model equation for the plume velocity as a function of time is proposed. Alternatively, the use of a static laser beam for observation enables reliable determination of plume ...

1997-01-01

13

High resolution transmission electron microscopy of partial states of oxygen order in YBa_2Cu_3O_z  

International Nuclear Information System (INIS)

This paper reports on high resolution electron microscopy used to investigate the effect of electron irradiation induced oxygen loss on the states of partial order in YBa_2Cu_3O_z. Contrast effects visible in the [001] zone image as a result of the degree of the out-of-plane correlation of these ordered states are investigated. Using statistical simulations to aid in the analysis of the HREM images, an interpretation based on a kinetically limited evolution of the variation of long range [001] ordering is proposed.

1990-04-16

14

Lithology and evolution of the crust-mantle boundary region in the southwestern Basin and Range province  

Energy Technology Data Exchange (ETDEWEB)

Seismic transects in this area show a strongly reflective Moho of generally low relief, which, in the area of modern transects, consists of a thin zone (< 2 km thick) of short reflectors. The upper mantle is transparent and has a P{sub n} of 7.8-8.0 km/s similar to much of the western US. A lower crustal zone, 2-13 km thick, has variable internal reflectivity and a relatively low velocity of 6.6-6.8 km/s. Upper mantle peridotite xenoliths show both ductile and brittle deformational features and have structures and composition affected by magmatic intrusion; intrusions form complex dike systems and extensive zones of grain boundary infiltration in peridotite xenoliths. Whereas melt infiltration preceded and followed ductile deformation, brittle deformation, represented by closely spaced joint systems and faults, followed ductile deformation and is related to the youngest magmatic episodes. Lower crustal xenoliths are ...

1990-01-10

15

The actin content of fibroblasts.  

UK PubMed Central (United Kingdom)

Cultures of chick skin fibroblasts were dissolved in solutions of sodium dodecyl sulphate, and their entire protein content was examined by gel electrophoresis. The most abundant species migrated in...Full Text Available

1975-05-01

16

A plasma process for the synthesis of cubic-shaped silicon nanocrystals for nanoelectronic devices  

International Nuclear Information System (INIS)

Low pressure silane plasmas are known for their ability to synthesize silicon nanoparticles via gas phase nucleation. While in the past this particle formation has often been considered from the viewpoint of a contamination problem in semiconductor processing, we here describe a silane low pressure plasma that enables the synthesis of highly oriented, cubic-shaped silicon nanocrystals with a rather monodisperse size distribution. These silicon nanocubes have successfully been used in the manufacture of single nanoparticle vertical transistors. We discuss the advantages of this new paradigm of building nanoelectronic devices. The plasma synthesis process is characterized in more detail than in prior work. The particle nucleation, growth and shape evolution are studied. Results indicate that the process provides two spatially distinct zones: a diffuse plasma for particle growth and a constricted plasma zone for particle ...

2007-04-21

17

Gas-dynamic signs of explosive eruptions of volcanoes. 2. Model of homogeneous-heterogeneous nucleation. Specific features of destruction of the cavitating magma  

British Library Electronic Table of Contents (United Kingdom)

The dynamics of state of the crystallite-containing magma is studied within the framework of the gas-dynamic model of bubble cavitation. The effect of crystallites on flow evolution is considered for two cases: where the crystallites are cavitation nuclei (homogeneous-heterogeneous nucleation model) and where large clusters of crystallites are formed in the magma in the period between eruptions. In the first case, decompression jumps are demonstrated to arise as early as in the wave precursor; the intensity of these jumps turns out to be sufficient to form a series of discrete zones of nucleation ahead of the front of the main decompression wave. Results of experimental modeling of an explosive eruption with ejection of crystallite clusters (magmatic ?bombs??) suggest that a cocurrent flow...

2009-01-01

18

Analysis of the mechanical properties of metal-ceramic interfaces using the four-point bending test: application to dental metal-ceramic couples (Pd-Ag, Pd-Au)  

International Nuclear Information System (INIS)

Different semi precious alloys (Pd-Ag, Pd-Au) have been studied after thermal oxidation treatments to analyze the mechanical improvement of the interface between the metal and the ceramic. Using the four point bending test, the authors have analyzed the different steps corresponding to the mechanical evolution of the bi-material : cracking energy on the surface, relaxation energy after first cracking, propagation energy of cracks at the interface zone. It has been shown that some alloys only have a high resistance to the interface cracking and the role played by the interface reactions to improve this property. (orig.).

1993-06-01

19

Aerial view of the depot zone of Bois des Serves.  

CERN Document Server

Aerial view of the depot zone of Bois des Serves.

1999-01-01

20

The separation of multiple forms of housefly 1,1,1-trichloro-2,2-bis-(p-chlorophenyl)-ethane (DDT) dehydrochlorinase from glutathione S-aryltransferase by electrofocusing and electrophoresis  

UK PubMed Central (United Kingdom)

Electrophoresis in a sucrose gradient at pH values between 5 and 8 separated housefly DDT [1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane] dehydrochlorinase into two major fractions....Full Text Available

1970-05-01

21

In the News...  

Science.gov (United States)

"Ejections. "Massive Star Evolution. "Binary Star Evolution ..... Binary Star Evolution. Stars in binary systems evolve individually and together ...

22

Detection of glycoproteins in the Acanthamoeba plasma membrane  

International Nuclear Information System (INIS)

In the present study the authors have shown that glycoproteins are present in the plasma membrane of Acanthamoeba castellanii by utilizing different radioactive labeling techniques. Plasma membrane proteins in the amoeba were iodinated by "1"2"5I-lactoperoxidase labeling and the solubilized radiolabeled glycoproteins were separated by lectin-Sepharose affinity chromatography followed by polyacrylamide gel electrophoresis. The periodate/NaB"3H_4 and galactose oxidase/NaB"3H_4 labeling techniques were used for labeling of surface carbohydrates in the amoeba. Several surface-labeled glycoproteins were observed in addition to a diffusely labeled region with M_r of 55,000-75,000 seen on electrophoresis, which could represent glycolipids. The presence of glycoproteins in the plasma membrane of Acanthamoeba castellanii was confirmed by metabolic labeling with ["3"5S]methionine followed by lectin-Sepharose affinity chromatography and polyacrylamide gel ...

23

Unclas  

Science.gov (United States)

Another difference lies in the speed of star evolution. 2. Computation of Stellar Structure and Their Evolution. The structure of stars at certain instants ...

24

Neutron star evolution with internal heating  

Science.gov (United States)

The thermal evolution predicted by current models of the superfluid-crust interaction is noted to

1989-01-01

25

Massive star evolution and SN 1987A  

Science.gov (United States)

The evolution of massive stars through hydrogen and helium burning is addressed. A set of stellar

1991-01-01

26

Geothermal Evolution of the Astrakhan Crest Region of the Pricaspian Basin, Russia  

CERN Document Server

Geothermal Evolution of the Astrakhan Crest Region of the Pricaspian Basin, Russia

2006-01-01

27

Evolution of ultraviolet dwarfs  

Science.gov (United States)

UV dwarf star evolution, using central and gap star models emphasizing photoneutrino emission

1969-01-01

28

Stage-specific protein synthesis during early embryogenesis in Drosophila melanogaster.  

UK PubMed Central (United Kingdom)

The changes in protein species synthesized during early Drosophila embryogenesis were characterized by two-dimensional electrophoresis. Of the 261 proteins scored, 68 (26%) show dramatic changes in...Full Text Available

1983-01-01

29

ProMoST: A tool for calculating the pI and molecular mass of phosphorylated and modified proteins on 2 dimensional gels  

UK PubMed Central (United Kingdom)

Protein modifications such as phosphorylation are often studied by two-dimensional gel electrophoresis since the perturbation in the protein’s pI value is readily detected by this method....Full Text Available

2009-01-01

30

Polyamine Oxidase from Water Hyacinth  

UK PubMed Central (United Kingdom)

Polyamine oxidase was purified to homogeneity from leaves of water hyacinth by the criterion of sodium dodecyl sulfate gel electrophoresis (SDS disc PAGE). The enzyme showed a high specificity for spermidine...Full Text Available

1987-12-01

31

Multiple integration sites for Moloney murine leukemia virus in productively infected mouse fibroblasts.  

UK PubMed Central (United Kingdom)

The integration sites for viral DNA in cells infected with Moloney murine leukemia virus (M-MuLV) were studied by restriction endonuclease cleavage of cellular DNA followed by electrophoresis in agarose...Full Text Available

1979-06-01

32

MudPIT Analysis: Application to Human Heart Tissue  

UK PubMed Central (United Kingdom)

Although two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) has been used as the standard proteomic approach for separating proteins in a complex mixture, this technique has many drawbacks....Full Text Available

2009-01-01

33

Improved Understanding of the Bacterial Vaginal Microbiota of Women before and after Probiotic Instillation  

UK PubMed Central (United Kingdom)

The vaginal bacterial microbiota of 19 premenopausal women was examined by PCR-denaturing gradient gel electrophoresis (DGGE) and sequencing of the V2-V3 region of the 16S rRNA gene. Ten of the women...Full Text Available

2003-01-01

34

Ethylene Regulates Monomeric GTP-Binding Protein Gene Expression and Activity in Arabidopsis1  

UK PubMed Central (United Kingdom)

Ethylene rapidly and transiently up-regulates the activity of several monomeric GTP-binding proteins (monomeric G proteins) in leaves of Arabidopsis as determined by two-dimensional gel electrophoresis...Full Text Available

2003-04-01

35

Disulfide Bonds and the Quaternary Structure of Factor VIII/von Willebrand Factor  

UK PubMed Central (United Kingdom)

Human Factor VIII/von Willebrand factor, purified by calcium citrate-cellulose chromatography and 4% agarose gel filtration was subjected to sodium dodecyl sulfate gel electrophoresis on gels containing...Full Text Available

1978-09-01

36

An evaluation of cerebrospinal fluid oligoclonal banding confirmed by immunofixation on agarose gel.  

UK PubMed Central (United Kingdom)

The cerebrospinal fluid (CSF) from 115 consecutive patients undergoing diagnostic lumbar puncture or myelography was examined to determine the usefulness of immunofixation, following agarose gel electrophoresis,...Full Text Available

1983-06-01

37

The Hydrodynamic Environment for the s Process in the He-Shell Flash of AGB Stars  

CERN Document Server

The He-shell flash convection in AGB stars is the site for the high-temperature component of the s-process in low- and intermediate mass giants, driven by the Ne22 neutron source. [...] The upper convection boundary plays a critical role during the H-ingestion episode that may lead to neutron-bursts in the most metal-poor AGB stars. We address these problems through global 3-dimensional hydrodynamic simulations including the entire spherical He-shell flash convection zone (as oposed to the 3D box-in-a-star simulations). An important aspect of our current effort is to establish the feasibility of our appoach. We explain why we favour the explicit treatment over the anelastic approximation for this problem. The simulations presented in this paper use a Cartesian grid of 512^3 cells and have been run on four 8-core workstations for four days to simulate ~5000s, which corresponds to almost ten convective turn-over times. The convection layer extends radially at the ...

2009-01-01

38

Recent historical changes on the Belgian Meuse  

International Nuclear Information System (INIS)

When a nuclear power station was installed on the Meuse in central Belgium, the impact of thermal, radioactive, and chemical waste on the water of the Neuse and on its biocenoses was studied. Three successive periods of development of the channel bed and the flood plain in Belgium have occurred, and their hydrological, physicochemical, and ecological consequences have been examined. Since the last century, the ecosystem of the Meuse has undergone, due to the increasing activity of man, modifications of increasing importance: marked reduction of the water flow, a drastic increase in the suspended material being transported, a degree of eutrophication of the water, and the disturbance of the original floral and faunal communities. The causes of this evolution of the Meuse can be itemized as different types of human interference in descending order of importance: (1) occupation of the catchment area; (2) encroachment on the flood plain; (3) encroachment on the channel ...

39

Hybridization and Modification of the Ni/C{sub 60} Composites  

Science.gov (United States)

Hybridization and thermal evolution of the Ni+C{sub 60} composites, deposited on Si(001) at room temperature, were studied using Scanning Electron Microscopy, {mu}-Raman spectroscopy and Rutherford Backscattering. As-deposited, the hybrid films exhibited a granular nano-structure with Ni nano-particles encapsulated in C{sub 60} polymerized rinds. The Ni and C (C{sub 60}) distributions in a top layer were found homogeneous with a stable Ni/C (C{sub 60}) ratio; in the larger depth the distributions were inhomogeneous and their ratio dramatically varied. At elevated temperatures, all structural parameters were changed. In the subsurface layer Ni- and C (C{sub 60})-rich zones were formed (due to the induced phase separation), C{sub 60}-molecules decayed and their fragments were transformed into amorphous carbon (a-C). The free volume distribution of the stressed hybrid matter was analyzed by the Hg marker that (in a form of vapors) in-diffused in ...

2009-03-10

40

Deposition and diagenesis of a cratonic Silurian platform reef, Pipe Creek Jr. , Indiana  

Energy Technology Data Exchange (ETDEWEB)

Petrographic and geochemical characteristics of the Pipe Creek Jr. paragenesis record the stratigraphic and burial evolution of the cratonic Silurian platform of Indiana during Late Silurian to Pennsylvanian. A variety of several diagenetic fluids acting over geological time affected the reef. The paragenetic sequence is as follows: (1) precipitation of turbid, fibrous, blotchy cathodoluminescent (CL) cement; (2) dolomitization of mud-rich facies; (3) precipitation of clear, zoned CL equant calcite cements; (4) fracturing and karst formation, partially filled by geopetal silt and sandstone; (5) precipitation of clear, dull CL, ferroan to nonferroan equant calcite cement, ferroan dolomite overgrowth and equant dolomite cement in moldic porosity, caves and fractures; (6) microdissolution and hydrocarbon emplacement; and (7) stylolitization. The New Albany Shale was both the hydrocarbon source and top seal to the fossil Pipe Creek Jr. oil field ...

1988-02-01

41

Comparative evaluation of the quantitative bone scintigraphy and the radiography in patients with ankylosing spondylitis  

International Nuclear Information System (INIS)

In 620 patients quantitative bone scintigraphy with "9"9"mTc pyrophosphate of the sacroiliac joints and of the spine was performed: 365 patients with confirmed ankylosing spondylitis, 125 patients with clinical radiological suspicion for ankylosing spondylitis (probable Bechterev) and control group of 130 healthy individuals. By comparison of the activity in zones of interest of the sacroiliac joints, the spine and sacrum, the following indices were determined: sacroiliac (separately for the left and right sacroiliac joints), index D_1_0/sacrum, index L_4/sacrum and index C_7/sacrum. The scintigraphic finding was compared to the X-ray one and to the radiological stage of the disease. A long-term follow-up of the patients was carried out during 1-6 years with scintigraphic, X-ray and clinical investigations. Emphasis was laid upon the posibilities for quantitative scintigraphy for early diagnostics of ankylosing spondylitis. The combination of scintigraphic with ...

42

Stellar evolution. II - The evolution of a 3 sun-mass star from the main sequence through core helium burning.  

Science.gov (United States)

Three Sun-mass star evolution from main sequence to helium exhaustion in core, noting chronology of

1965-01-01

43

GALAXY EVOLUTION EXPLORER (GALEX) GUEST ... - GALEX - NASA  

Science.gov (United States)

star evolution, globular cluster structure and evolution, massive stars, supernova remnants, reflection nebulae, interstellar dust, structure of the ISM, ...

44

GALAXY EVOLUTION EXPLORER (GALEX) - HEASARC - NASA  

Science.gov (United States)

These include, but are not limited to: stellar winds and outflows, post-main- sequence stellar evolution, binary/multiple star evolution, globular cluster structure ...

45

GALAXY EVOLUTION EXPLORER (GALEX) - GALEX - NASA  

Science.gov (United States)

These include, but are not limited to: stellar winds and outflows, post-main- sequence stellar evolution, binary/multiple star evolution, globular cluster structure ...

46

Utilizing the right mix of environmental cleanup technologies  

International Nuclear Information System (INIS)

The Savannah River Site (SRS) is a 310-square-mile United States Department of Energy nuclear facility located along the Savannah River near Aiken, South Carolina. During operations, which started in 1951, hazardous substances (chemicals and radionuclides) were released to the environment. The releases occurred as a result of inadvertent spills and waste disposal in unlined pits and basins which was common practice before environmental regulations existed. The hazardous substances have migrated to the vadose zone and groundwater in many areas of the SRS, resulting in 515 waste units that are required by environmental regulations, to undergo characterization and, if needed, remediation. In the initial years of the SRS environmental cleanup program (early 1990's), the focus was to use common technologies (such as pump and treat, air stripping, excavation and removal) that actively and tangibly removed contamination. Exclusive use of these technologies required ...

2007-09-02

47

Molecular dynamics studies of silicon ion implantation  

Energy Technology Data Exchange (ETDEWEB)

Results are presented of molecular dynamics (MD) studies of 1-10 keV displacement cascades in silicon. At these energies, the simulations couple directly to experimental observations of low energy implantation in silicon for shallow junction formation. The simulations are performed with the Stillinger-Weber potential for silicon in computational cells with up to 3.5x10{sup 5} atoms. The author employs periodic boundary conditions in the [100] and [010] directions and a free surface on the top (001) plane. The author discusses the results in terms of the structural evolution and the dynamics of the cascade zones. For sufficiently high energy recoils (>2 KeV), the cascades produce locally molten zones that result in the formation of amorphous silicon pockets upon recrystallization. Frenkel pairs are also produced during the cascade, although their number is very small (less than 10% of the binary collision predictions). ...

1994-12-31

48

Imaging of reflection seismic and radar wavefields: Monitoring of steam-heated oil reservoirs and characterization of nuclear waste repositories  

Energy Technology Data Exchange (ETDEWEB)

A new three-dimensional (3D) acoustic modelling method was developed using a first-order hyperbolic wave system which was solved with explicit finite dfferences. The numerical solution of the 3D wave system provides a useful method for simulating evolution of a pressure field corresponding to compressional type waves. Existing two-dimensional (2D) elastic modelling algorithms were modified and fine-tuned for computationally efficient and realistic wave propagation simulations in complex structures. An original formulation of the 3D reverse time migration method was developed which is very accurate, does not suffer from unwanted evenescent energy, can image dips beyond 90{degree}, and does not generate multiple energy. Two case studies were performed that involved steam stimulation projects in the Cold Lake deposit. Simulations were performed during different phases of the steam stimulation process to examine the relation between reservoir properties and conditions ...

1994-12-31

49

Studies on current distribution in electrochemical cells  

Energy Technology Data Exchange (ETDEWEB)

Three studies of electrochemical current distribution have been performed using potential-theory models and the boundary-element method (BEM). (1) The steady-state behavior of cells with nonuniform current density over a passivating anode is investigated. Current distributions calculated for a test cell, using the measured kinetic behavior of nickel in acid-nickel-sulfate solution, are compared to estimates from earlier models. Although current-density profiles determined by weight loss on a segmented rotating cylinder agreed satisfactorily with model calculations, the measured length of the passive zone exceeds the theoretical value. The model's applicability to anodic protection is demonstrated for a stainless-steel sulfuric-acid holding tank. (2) A model is established to describe the effects of attached bubbles on the potential drop at gas-evolving electrodes including: (1) ohmic obstruction within the electrolyte; (2) area masking on the electrode ...

1986-08-01

50

Zone mapping application for precision-farming: a decision support tool for variable rate application  

British Library Electronic Table of Contents (United Kingdom)

A web-based decision support tool, zone mapping application for precision farming (ZoneMAP, External Reference Not Shown ), has been developed to automatically determine the optimal number of management zones and delineate them using satellite imagery and field data provided by users. Application rates, such as of fertilizer, can be prescribed for each zone and downloaded in a variety of formats to ensure compatibility with GPS-enabled farming equipment. ZoneMAP is linked to Digital Northern Great Plains, a web-based application which hosts an archive of satellite imagery, as well as high resolution imagery from airborne sensors. Management zones created by ZoneMAP mapped natural variation of the soil organic matter and other nutrients relatively well and were consistent with zone maps cre...

2010-01-01

51

Nobel prizes  

Energy Technology Data Exchange (ETDEWEB)

The nuclear reactions are described which govern the stellar evolution.

1983-12-01

53

In The News ... - NASA  

Science.gov (United States)

Binary Star Evolution. Stars in binary systems evolve individually and together. " individually: evolution follows normal progression based on ...

55

Computer codes for the determination of air flow in buildings; Rechenprogramme zur Bestimmung der Luftstroemungen in Gebaeuden  

Energy Technology Data Exchange (ETDEWEB)

The report provides and overview of calculation models for the simulation of airflows and deals comprehensively with field and multi-zone models as well as the coupling of individual zone and multi-zone models. Examples of calculations are given. figs., tabs., refs.

1994-12-31

56

Amino acid substitutions in inherited albumin variants from Amerindian and Japanese populations  

International Nuclear Information System (INIS)

The authors report an effort to determine the basis for the altered migration of seven inherited albumin variants detected by one-dimensional electrophoresis in population surveys involving tribal Amerindians and Japanese children. An amino acid substitution has thus far been determined for four of the variants. The randomness in the albumin polypeptide of these and the other sixteen independently ascertained amino acid substitutions of albumin and proalbumin thus far established was analyzed; the clustering of eight of these at two positions in the six-amino acid propeptide sequence seems noteworthy. By comparison with other proteins studied by electrophoresis, albumin exhibits average variability. It is a paradox that individuals who, for genetic reasons, lack albumin exhibit no obvious ill effects; yet, electrophoretic variants of albumin are no more numerous than are variants of proteins, the absence of which results in severe disease.

58

Infrared processes in the auroral zone  

International Nuclear Information System (INIS)

... aurorae carbon dioxide emission spectra infrared radiation nitrogen nitrogen

8432-01-01

61

Temporal patterns of protein phosphorylation after angiotensin II, A23187 and/or 12-O-tetradecanoylphorbol 13-acetate in adrenal glomerulosa cells.  

UK PubMed Central (United Kingdom)

The temporal patterns of protein phosphorylation in the adrenal glomerulosa cell were analysed by two-dimensional electrophoresis after stimulation with 10 nM-angiotensin II or various agents [10 nM-12-O-tetradecanoylphorbol...Full Text Available

1986-09-15

62

Purification by Immunoadsorption and Immunochemical Properties of NADP-Dependent Malic Enzymes from Leaves of C3, C4, and Crassulacean Acid Metabolism Plants  

UK PubMed Central (United Kingdom)

NADP:malic enzyme from corn (Zea mays L.) leaves was purified by conventional techniques to apparent homogeneity as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis....Full Text Available

1990-03-01

63

Lipophilic technetium complexes. Technetium chelates of some O, N, S donor Schiff bases  

Energy Technology Data Exchange (ETDEWEB)

Dianionic tridentate, O, N, S, Schiff bases derived from salicylaldehyde and 2-mercapto-amines react with Tc(V) gluconate to form radiochemically pure neutral Tc chelates. The existence of lipophilic Tc complexes could be proved by high voltage electrophoresis, thin layer chromatography and octanol/water partition coefficients. 11 refs.

1984-04-02

64

Lipophilic technetium complexes. Technetium chelates of some O, N, S donor Schiff bases  

International Nuclear Information System (INIS)

Dianionic tridentate, O, N, S Schiff bases derived from salicylaldehyde and 2-mercapto-amines react with Tc(V) gluconate to form radiochemically pure neutral Tc chelates. The existence of lipophilic Tc complexes could be proved by high voltage electrophoresis, thin layer chromatography and octanol/water partition coefficients. (author).

1984-04-01

65

Formation and stability of astatide-mercury complexes  

International Nuclear Information System (INIS)

The formation of astatide-mercury complexes was investigated in aqueous solutions.The obtained complexes were examined by paper electrophoresis. It was found that Hg(OH)At and Hg(OH)I complexes were formed in neutral solution. The stability constants of the obtained complexes were determined by ion-exchange. The preliminary results indicate that the complex of mercury with astatide is much more stable than similar complexes with iodide. (author)

2006-04-01

66

Double minutes arise from circular extrachromosomal DNA intermediates which integrate into chromosomal sites in human HL-60 leukemia cells.  

UK PubMed Central (United Kingdom)

Amplification of oncogenes has been found to be an important prognostic factor in behavior of patients' malignancies. In this study we have used new gel electrophoresis techniques to follow the location...Full Text Available

1990-06-01

67

Antimicrobial resistance, virulence-associated genes, and pulsed-field gel electrophoresis profiles of Salmonella enterica subsp. enterica serovar Typhimurium isolated from piglets with diarrhea in Korea  

UK PubMed Central (United Kingdom)

Salmonella enterica subsp. enterica serovar Typhimurium was isolated from diarrheic piglets in 2 periods, 2000–2001 (n = 25) and 2005–2006...Full Text Available

2011-01-01

68

A Two-Dimensional Protein Gel Electrophoresis Study of the Heat Stress Response of Bacillus subtilis Cells during Sporulation  

UK PubMed Central (United Kingdom)

The heat resistance of spores of Bacillus subtilis formed at 30°C was enhanced by pretreatment at 48°C for 30 min, 60 min into sporulation, for all four strains examined....Full Text Available

2000-09-01

69

Sea-level rise and coastal zone management  

Energy Technology Data Exchange (ETDEWEB)

Greenhouse-effect induced climate change repercussions will, via the catchment areas of big rivers, eventually arrive in amplified form at the far downstream coastal zones of the world. In the coastal zone these imported problems will add to the locally exerted climate change effects, while the climate change induced sea-level rise will attack the coastal zone from the other side, both by flooding and by saline groundwater intrusion. These multiple problems will hit the coastal zone, which is already under increasing stress. The combined threats require fast and massive support for national Coastal Zone Management capabilities, which could help to limit the damage and to support planning for sustainable development. Recommendations are presented to facilitate implementation of Coastal Zone Management units in all coastal countries by the year 2000.

1992-09-01

70

Safe ageing management of nuclear power plants: An European synthesis  

International Nuclear Information System (INIS)

Ageing of nuclear power plants means evolution of material or equipment properties on one side, and evolution of personnel skill and procedure adequacy on the other side, both of which, after a certain time, may not be compatible with the required safety provisions, or with an economic operation of the plant. Repair or replacement of components, as well as change in service conditions for a better compatibility with component reduced capabilities can be used to mitigate ageing effects. The paper summarises the results of a study conducted in this field with the support of the European Commission. It presents: the synthesis of the work done under international auspices, and in the European context; the comparison of ageing management approaches used in several European countries with international recommendations; the summary of the various potential phenomena and their governing parameters, the methods of in-service ageing identification and ...

2002-11-04

71

Multi-scale modeling of fiber and fabric reinforced cement based composites  

Science.gov (United States)

With an increased use of fiber reinforced concrete in structural applications, proper characterization techniques and development of design guides are needed. This dissertation presents a multi-scale modeling approach for fiber and fabric reinforced cement-based composites. A micromechanics-based model of the yarn pullout mechanism due to the failure of the interfacial zone is presented. The effect of mechanical anchorage of transverse yarns is simulated using nonlinear spring elements. The yarn pullout mechanism was used in a meso-scale modeling approach to simulate the yarn bridging force in the crack evolution process. The tensile stress-strain response of a tension specimen that experiences distributed cracking can be simulated using a generalized finite difference approach. The stiffness degradation, tension stiffening, crack spacing evolution, and crack width characteristics of cement composites can be derived using ...

2008-01-01

72

X-ray Emission as a Probe of the Wind-Driven Shock in WR 140  

Science.gov (United States)

single star evolution. To understand the evolution of massive stars and their role in shaping the galaxy, understanding of the distribution of ...

73

Spatiotemporal Evolution of the fMRI Response to Ultrashort Stimuli  

UK PubMed Central (United Kingdom)

The specificity of the hemodynamic response function (HRF) is determined spatially by the vascular architecture and temporally by the evolution of hemodynamic changes. The stimulus duration...Full Text Available

2011-01-26

74

On Optically Thick Condensations in Planetary Nebulae NASA, Goddard  

Science.gov (United States)

effect of central star evolution would be to produce a thinner boundary, but the results of ... indicate that central star evolution may be neglected when ...

75

NASA Research Announcement: GALEX GI Program Cycle 2 - GALEX - NASA  

Science.gov (United States)

These include, but are not limited to: stellar winds and outflows, post-main- sequence stellar evolution, binary/multiple star evolution, globular cluster ...

76

NASA Research Announcement: GALEX GI Program Cycle 1 - GALEX - NASA  

Science.gov (United States)

These include, but are not limited to: stellar winds and outflows, post-main- sequence star evolution, binary star evolution, globular cluster structure and ...

77

Human-modified ecosystems and future evolution  

UK PubMed Central (United Kingdom)

Our global impact is finally receiving the scientific attention it deserves. The outcome will largely determine the future course of evolution. Human-modified ecosystems are shaped by our activities...Full Text Available

2001-05-08

78

Genomic view of the evolution of the complement system  

UK PubMed Central (United Kingdom)

The recent accumulation of genomic information of many representative animals has made it possible to trace the evolution of the complement system based on the presence or absence of each complement...Full Text Available

2006-09-01

79

An Input to the UVOIR Panel Of the AASC April ... - PlanetQuest - NASA  

Science.gov (United States)

Binary Star Evolution. The evolution of close binary stars can be very different from that of wide binaries of isolated stars. If the stars are close enough ...

80

Structural evolution of Lake Superior II: Eastern basin  

Energy Technology Data Exchange (ETDEWEB)

The authors have interpreted 1,400 km of industry and government multichannel seismic reflection data from eastern Lake Superior. Seismic sequences have been identified by using reflection character and reflector terminations and truncations. This framework, coupled with outcrop information, has allowed them to assign lithologic units to some of these reflectors and reconstruct the timing and geometry of structures within the basin. The authors have mapped the Base Jacobsville-Bayfield Group/Top oronto Group, Base oronto Group/Top Keweenawan volcanics, and Basement as well as several reflectors internal to these groups. Integration of gravity and magnetic data with the seismic grid permits regional mapping of faults and folds between seismic lines. In the eastern part of the basin, high-angle basement-involved reverse faults, such as the southeastern combination of the Keweenaw fault, trend NNW-SSE, while broad folds trend E-W. The Keweenaw fault is a complex structural ...

1992-01-01

81

Real World Evaluation of Dual-Zone ICD and CRT-D Programming Compared to Single-Zone Programming: The ALTITUDE REDUCES Study  

British Library Electronic Table of Contents (United Kingdom)

Tachycardia Detection, ICD, CRT-D Devices, Appropriate and Inappropriate Shock.-Introduction: We evaluated the frequency of appropriate and inappropriate shocks and survival in patients using dual-zone programming versus single-zone programming. Methods and Results: For the ALTITUDE REDUCES study, patients were followed for 1.6 1.1 years. The 12-month incidence of any shock was lower for dual-versus single-zone programmed detection at rates -170 bpm and between 170-200 bpm (P < 0.001). Appropriate shock rates at 1 year were also lower with dual-zone programming in these rate intervals (single zone 9.1%, 5.4%, P < 0.001, dual zone 6.7%, 4.7%, P < 0.02). There were no detectable differences between single- and dual-zone shock incidence at detection rates - 200 bpm (P = 0.14). Inappropriate s...

2011-01-01

82

Geological evolution of the center-southern portion of the Guyana shield based on the geochemical, geochronological and isotopic studies of paleoproterozoic granitoids from southeastern Roraima, Brazil; Evolucao geologica da porcao centro-sul do escudo das Guianas com base no estudo geoquimico, geocronologico e isotopico dos granitoides paleoproterozoicos do sudeste de Roraima, Brasil  

Energy Technology Data Exchange (ETDEWEB)

This study focuses the granitoids of center-southern portion of Guyana Shield, southeastern Roraima, Brazil. The region is characterized by two tectonic-stratigraphic domains, named as Central Guyana (GCD) and Uatuma-Anaua (UAD) and located probably in the limits of geochronological provinces (e.g. Ventuari-Tapajos or Tapajos-Parima, Central Amazonian and Maroni-Itacaiunas or Transamazon). The aim this doctoral thesis is to provide new petrological and lithostratigraphic constraints on the granitoid rocks and contribute to a better understanding of the origin and geo dynamic evolution of Guyana Shield. The GCD is only locally studied near to the UAD boundary, and new geological data and two single zircon Pb-evaporation ages in mylonitic biotite granodiorite (1.89 Ga) and foliated hastingsite-biotite granite (1.72 Ga) are presented. These ages of the protholiths contrast with the lithostratigraphic picture in the other areas of Cd (1.96-1.93 Ga). Regional mapping, ...

2006-07-01

83

Spatially resolved methane band photometry of Jupiter. III - Cloud vertical structures for several axisymmetric bands and the Great Red Spot  

Energy Technology Data Exchange (ETDEWEB)

The paper presents cloud structure models for Jupiter's Great Red Spot, Equatorial and North Tropical Zones, North and South Temperate Zones, and North and South Polar Regions. The models are based on images of Jupiter in three methane bands and nearby continuum radiative transfer calculations include multiple scattering and absorption from three aerosol layers. The model results include the transition in the upper-cloud altitude to 3 km lower altitude from the tropical zones to temperate zones and polar regions, a N/S asymmetry in cloud thickness in the tropical and temperature zones, and the presence of aerosols up to about 0.3 bar in the Great Red Spot and Equatorial Zone. It is concluded that polarization data are sensitive to aerosols in and above the upper cloud layer but insensitive to deeper cloud structure.

1980-02-01

84

The beginning of a new science  

International Nuclear Information System (INIS)

The evolution of the study of extra-terrestrial neutrinos over the 45 years since their discovery.

85

Surface brightness, galaxy evolution and cosmology  

Energy Technology Data Exchange (ETDEWEB)

The Thomsen and Frandsen (1983) cosmological test employing the observed correlation between elliptical galaxy surface brightness and scale size in order to avoid problems due to dynamical evolution is presently extended to make use of arbitrary galaxy samples. The explicit dependence on stellar evolution is also demonstrated. On the assumption that this evolution is calculable, an equation for the deceleration parameter entirely in terms of observables is derived. The test is applied to two available samples. 25 references.

1985-01-01

86

Probing Neutron Star Evolution with Gamma Rays  

Science.gov (United States)

The research sponsored by this grant was conducted in two fields of high-energy astrophysics:

1996-01-01

87

Neutrino processes and pair formation in massive stars and supernovae.  

Science.gov (United States)

Neutrino processes role in star evolution and onset of supernovae explosion

1964-01-01

88

Life of the stars  

Energy Technology Data Exchange (ETDEWEB)

Stars and star evolution are discussed, including supernovae, nucleosynthesis, and mass-luminosity and Hertzsprung--Russell diagrams./aip/.

1988-09-20

89

Isopod Systematics and Evolution  

Science.gov (United States)

... inferences. Thatcher carries the banner for studies of isopod parasites of fishes of the Amazonian region. This fauna ... ...

90

Virology Experts in the Boundary Zone Between Science, Policy and the Public: A Biographical Analysis  

UK PubMed Central (United Kingdom)

This article aims to open up the biographical black box of three experts working in the boundary zone between science, policy and public debate. A biographical-narrative approach is used to analyse...Full Text Available

2010-06-01

91

Subventricular Zone Cell Migration: Lessons from Quantitative Two-Photon Microscopy  

UK PubMed Central (United Kingdom)

Neuroblasts born in the adult subventricular zone (SVZ) migrate long distances in the rostral migratory stream (RMS) to the olfactory bulbs where they integrate into circuitry as functional interneurons....Full Text Available

92

Some properties of low-mass stellar models with chemically inhomogeneous neutral-stability zones  

Energy Technology Data Exchange (ETDEWEB)

Several low-mass models with an inhomogeneous radiative core and a convective envelope are investigated, the entire core or its upper portion being treated as a zone of neutral stability. Mixing by convective overshoot will then give rise to unstable structure.

1983-03-01

93

KJNWFZ Concept Paper May6-2010  

Wastenet

KOREA-JAPAN NUCLEAR WEAPON FREE ZONE (KJNWFZ) CONCEPT PAPER ...A Korea-Japan2 Nuclear Weapon Free Zone (hereafter KJNWFZ) is a new concept.Once realized, ...Finally, we outline the key elements of the Korea-Japan NWFZ proposed in this paper, noting

94

Impact of extreme events on coastal zones and small islands in the context of climate change  

Energy Technology Data Exchange (ETDEWEB)

The paper presents a review of the current state of knowledge on the likely impacts of extreme weather and climate events on coastal zones and small islands in the context of climate change. Possible response options, including prevention, preparedness and adaptation, are indicated.

1995-07-10

95

Experimental autoimmune encephalomyelitis mobilizes neural progenitors from the subventricular zone to undergo oligodendrogenesis in adult mice  

UK PubMed Central (United Kingdom)

The destiny of the mitotically active cells of the subventricular zone (SVZ) in adult rodents is to migrate to the olfactory bulb, where they contribute to the replacement of granular and periglomerular...Full Text Available

2002-10-01

96

Erythropoietin Attenuates Brain Injury, Subventricular Zone Expansion, and Sensorimotor Deficits in Hypoxic-Ischemic Neonatal Rats  

UK PubMed Central (United Kingdom)

The aim of this study was to investigate the effect of erythropoietin (EPO) on histological brain injury, subventricular zone (SVZ) expansion, and sensorimotor function deficits induced by hypoxia-ischemia...Full Text Available

2008-06-01

97

Determination of size distribution of Guinier-Preston zones in Al-Ag alloys by small-angle x-ray scattering method  

International Nuclear Information System (INIS)

Small-angle X-ray scattering method recognised to be very useful in the studies of structural problems of materials in homogeneous in nanoscale. Studies by small-angle X-ray scattering on the Al-Ag alloys are presented. The size distributions of spherical Guinier-Person zones were calculated using Vonk's and Glatter's methods. Small-angle X-ray scattering studies were performed on Al-5.0 at.%Ag alloy containing Guinier-Preson zones in the #eta#-state. For this alloy one can assume that scattering particles are of spherical shape, have uniform electron density and scatter independently. Moreover, the size distributions were calculated for Al-1.6 at.%Ag alloy containing Guinier-Preston zones in #epsilon#-state (scattering particles with not uniform electron density). Both, Vonk's and Glatter's, methods gave similar size distributions. Profiles of size distributions for Guinier-Preston zones in ...

2001-09-23

98

Cumulative effects of protracted irradiation of Chernobyl exclusive zone plants  

International Nuclear Information System (INIS)

The biological and radiobiological peculiarities of seeds and seedlings of the Rumex confertus and Lupinus polycolor plants, which grown during several generations in plots with different level of radionuclide pollution of the Chernobyl exclusive zone have been investigated.

2005-01-01

99

Computer simulation of protein self-association during small-zone gel filtration. Estimation of equilibrium constants.  

UK PubMed Central (United Kingdom)

A simulation is developed that qualitatively describes the small-zone-gel-filtration behaviour of a reversibly associating protein. The results reflect the dependence of the apparent molecular weight...Full Text Available

1981-04-01

100

Chronic inflammatory disease, lymphoid tissue neogenesis and extranodal marginal zone B-cell lymphomas  

UK PubMed Central (United Kingdom)

Chronic autoimmune or pathogen-induced immune reactions resulting in lymphoid neogenesis are associated with development of malignant lymphomas, mostly extranodal marginal zone B-cell lymphomas (MZBCLs)....Full Text Available

2009-08-01

101

A study of membrane protein defects and alpha hemoglobin chains of red blood cells in human beta thalassemia  

International Nuclear Information System (INIS)

The soluble pool of alpha hemoglobin chains present in blood or bone marrow cells was measured with a new affinity method using a specific probe, beta A hemoglobin chain labeled with ["3H]N-ethylmaleimide. This pool of soluble alpha chains was 0.067 #+-# 0.017% of hemoglobin in blood of normal adult, 0.11 #+-# 0.03% in heterozygous beta thalassemia and ranged from 0.26 to 1.30% in homozygous beta thalassemia intermedia. This elevated pool of soluble alpha chains observed in human beta thalassemia intermedia decreased 33-fold from a value of 10% of total hemoglobin in bone marrow cells to 0.3% in the most dense red blood cells. The amount of insoluble alpha chains was measured by using the polyacrylamide gel electrophoresis in urea and Triton X-100. In beta thalassemia intermedia the amount of insoluble alpha chains was correlated with the decreased spectrin content of red cell membrane and was associated with a decrease in ankyrin and with other abnormalities of ...

102

The interaction zone of a #gamma##gamma# collider at TESLA  

International Nuclear Information System (INIS)

German 2003 p. 24 Germany Klemz, G. Moenig, K. Sekaric, J. Stahl,

103

THE EFFECT OF THE ICE-SEPARATION CURVE ON THE ...  

Science.gov (United States)

... However, the solution of the Stefan problem in this context becomes abruptly complicated, since within each zone, the differential equations ...

104

NAME=\\  

Wastenet

...Benthic Marine Bioregionalisation of Australia's Exclusive Economic Zone The benthic (sea floor) component of the National Marine Bioregionalisation covers the 80% of Australia's ... Exclusive Economic Zone that lies beyond the continental shelf break. It provides a description of patterns of biological distributions and physical habitats on the seafloor....sea floor) component of the National Marine Bioregionalisation covers the 80% of Australia's Exclusive Economic Zone that lies beyond the continental shelf break. It provides a ... Benthic Marine Bioregionalisation of Australia's Exclusive Economic Zone Change text size Skip to content Marine Bioregional Planning resources Search: About us Contact us You ...

105

Multizone Modular Artillery Propelling Charge Studies.  

Science.gov (United States)

... GUN PROPELLANTS, GUN CHAMBERS, PROPELLANT GRAINS, HOWITZERS, COMBUSTIBLE CARTRIDGE CASES, ZONE CHARGES. ...

1985-02-01

106

In vitro MRI of brain development  

International Nuclear Information System (INIS)

In this review, we demonstrate the developmental appearance, structural features, and reorganization of transient cerebral zones and structures in the human fetal brain using a correlative histological and MRI analysis. The analysis of postmortem aldehyde-fixed specimens (age range: 10 postovulatory weeks to term) revealed that, at 10 postovulatory weeks, the cerebral wall already has a trilaminar appearance and consists of: (1) a ventricular zone of high cell-packing density; (2) an intermediate zone; (3) the cortical plate (in a stage of primary consolidation) with high MRI signal intensity. The anlage of the hippocampus is present as a prominent bulging in the thin limbic telencephalon. The early fetal telencephalon impar also contains the first commissural fibers and fornix bundles in the septal area. The ganglionic eminence is clearly visible as an expanded continuation of the proliferative ventricular ...

2006-02-01

108

Simulation of DNA electrophoresis through microstructures  

British Library Electronic Table of Contents (United Kingdom)

The dependence of the mobility of DNA molecules through an hexagonal array of micropillars on their length and the applied electric field was investigated and it was found that mobility is a nonmonotonic function of their length. Results also revealed that the size dependence of the DNA mobility depends on the applied electric field and there is a crossover around E 25 V/cm for the mobility of l-DNA and T4-DNA. These observations are explained in terms of the diffusion process inside the structure affected by the solvent and are modeled using the Langevin and its corresponding Fokker-Planck equations. The phenomenon is generalized under three regimes in a phase diagram relating the electric field and the DNA lengths. The model and the associated phase diagram described here provide an expl...

2007-01-01

109

Preparation of reactor tube by welding a porous membrane with a non-porous ceramic tube  

Energy Technology Data Exchange (ETDEWEB)

In the course of designing a catalytic porous membrane reactor for experimental studies, both inside and outside of the non-reaction zones as well as the two ends of the membrane need to be completely sealed to ensure that there is no flow across the membrane in the non-reaction zone. Experiments show that up to 50% of the total flow across the membrane may be contributed by the axial flow along the wall of the non-reaction zones if only one side of the membrane is sealed. Another problem that cannot be solved by sealing is the capillary flow of the catalyst along the tube wall into the non-reaction zones when the catalyst is doped on the membrane. One of the best ways to avoid this axial flow of catalyst would be to use non-porous tubes in the non-reaction zones and join them with the porous membrane tube. In doing so, the cost of the membrane reactor could be reduced simply ...

1994-12-31

110

Photoacoustic imaging using an ultrasonic Fresnel zone plate transducer  

International Nuclear Information System (INIS)

A photoacoustic (PA) imaging system based on an ultrasonic Fresnel zone plate (FZP) transducer is developed for the purpose of imaging biological tissue. This FZP transducer has a two-zone negative zone plate piezoelectric material pattern, and an optical fibre is integrated with the transducer on the symmetric axis of the zone plates to deliver laser pulses to the sample. The focal characteristic of the FZP transducer is analysed by theoretical prediction and experimental measurement, and the measured results are in good agreement with the predicted results. The limited-field back-projection deconvolution algorithm combined with the coherence-factor weighting technique is used to reconstruct the optical absorption distribution. The experiments were performed with phantoms and the blood vessels of chicken embryo chorioallantoic membrane. The results demonstrate that PA imaging using the FZP transducer ...

2008-05-07

111

Microstructure and mechanical properties of magnesium alloy AZ31B laser beam welds  

International Nuclear Information System (INIS)

Microstructure and properties of a Mg AZ31B laser beam weld without filler are studied using electron microscopy, X-ray diffraction and mechanical tests. The microstructure of the weld is characterized by a narrow heat affected zone, columnar grains and precipitate coarsening in the fusion zone. Texture in the fusion zone is significantly different from the texture of the base material. The residual stress distribution observed is similar at the top and the bottom of the weld, maximum tensile residual stress values are observed in the fusion zone. Tensile tests reveal differences in the mechanical behavior of the fusion zone and the parent material, which can be related to the differences of texture and the resulting deformation mechanisms.

2008-06-25

112

Fisheries development in Vietnam: A case study in the exclusive economic zone  

British Library Electronic Table of Contents (United Kingdom)

Pursuant to statement issued by the Government of Vietnam on 12 May 1977, on the territorial sea, the contiguous zone, the exclusive economic zone (EEZ) and the continental shelf of Vietnam, and according to the provisions of the LOS Convention, the EEZ of Vietnam extends principally up to 200NM from the baseline, and the area of EEZ amounts to about one million square km including the Hoang Sa (Paracel) and Truong Sa (Spratly) Islands [The declaration of the Government of Vietnam on the territorial sea, contiguous zone, exclusive economic zone and continental shelf, Hanoi, 1977]. The establishment of EEZ has significantly changed circumstances for the fisheries sector in Vietnam.Recently, even though the adaptation of new techniques and technologies to the fisheries sector has been somewh...

2007-01-01

113

MONTE CARLO SIMULATIONS OF GLOBULAR CLUSTER EVOLUTION. V. BINARY STELLAR EVOLUTION  

International Nuclear Information System (INIS)

We study the dynamical evolution of globular clusters containing primordial binaries, including full single and binary stellar evolution using our Monte Carlo cluster evolution code updated with an adaptation of the single and binary stellar evolution codes SSE and BSE from Hurley et al. We describe the modifications that we have made to the code. We present several test calculations and comparisons with existing studies to illustrate the validity of the code. We show that our code finds very good agreement with direct N-body simulations including primordial binaries and stellar evolution. We find significant differences in the evolution of the global properties of the simulated clusters using stellar evolution compared with simulations without any stellar evolution. In particular, we find that the mass loss from the ...

2010-08-10

114

Validation of flux mapping system (FMS) of TAPP-4 with TRIVENI  

International Nuclear Information System (INIS)

The reactor core of TAPP-3 and 4 is divided into 14 power zones for spatial power control. Corresponding to each zone is a light water zonal compartment. The 14 ZCCs are located in two radial planes, each containing 7 ZCCs. For each zone, power measurement is carried out using three cobalt Self Powered Neutron Detectors (SPNDs) at appropriate locations close to the respective ZCC. Since the zone power as obtained by the true average of the healthy zone control detector (ZCD) readings belonging to a particular zone may not correspond to its actual power because these 3 detectors per zone, measure only point fluxes but the zone extends over a large core region. Therefore accurate estimation of zone power calibration factors is required to estimate the zone powers and also to ...

2006-11-13

115

Anomalous zones in Gulf Coast Salt domes with special reference to Big Hill, TX, and Weeks Island, LA  

Energy Technology Data Exchange (ETDEWEB)

Anomalous features in Gulf Coast Salt domes exhibit deviations from normally pure salt and vary widely in form from one dome to the next, ranging considerably in length and width. They have affected both conventional and solution mining in several ways. Gas outbursts, insolubles, and potash (especially carnallite) have led to the breakage of tubing in a number of caverns, and caused irregular shapes of many caverns through preferential leaching. Such anomalous features essentially have limited the lateral extent of conventional mining at several salt mines, and led to accidents and even the closing of several other mines. Such anomalous features, are often aligned in anomalous zones, and appear to be related to diapiric processes of salt dome development. Evidence indicates that anomalous zones are found between salt spines, where the differential salt intrusion accumulates other materials: Anhydrite bands which are relatively strong, and ...

1993-07-01

116

Evaluation of microstructures and mechanical properties in the HAZ of SA 508 Gr.4N Low Alloy Steel  

International Nuclear Information System (INIS)

In the heat-affected zones (HAZ) of low alloy steels used for nuclear pressure vessel, microstructural changes, such as grain coarsening, carbide precipitation, and martensite formation, generally occur and cause a deterioration of toughness and an increase in sensitivity to brittle fracture. Metallographic analyses of low alloy steel welds reveal significantly different regions in HAZ microstructures. In 2-pass welds, there were seven characteristic regions in the HAZ determined by the peak temperature, to which the region was exposed during the weld thermal cycle: a coarse-grained region, a fine-grained region, an intercritical region, and subcritical region. The coarse-grained region can be categorized into four zones according to the reheating temperature as follows : an unaltered coarse-grained zone (UCGHAZ), a supercritically reheated coarse grained zone (SCRCGHAZ), an intercritically reheated ...

2006-11-02

117

Star-formation triggers and chemical evolution  

Energy Technology Data Exchange (ETDEWEB)

Comparative studies of flocculent and grand-design spirals suggest that density waves are not the predominant trigger of star formation in most galaxies. Implications for chemical evolution are profound. It may be possible to ignore the details of the spiral-wave phenomenon in research aimed at unifying the chemical properties of spiral disks. 16 references.

1986-10-01

118

Origins, evolution, and phenotypic impact of new genes  

UK PubMed Central (United Kingdom)

Ever since the pre-molecular era, the birth of new genes with novel functions has been considered to be a major contributor to adaptive evolutionary innovation. Here, I review the origin and evolution...Full Text Available

2010-10-01

119

On Being the Right Size: The Impact of Population Size and Stochastic Effects on the Evolution of Drug Resistance in Hospitals and the Community  

UK PubMed Central (United Kingdom)

The evolution of drug resistant bacteria is a severe public health problem, both in hospitals and in the community. Currently, some countries aim at concentrating highly specialized services in large...Full Text Available

2011-04-01

120

Neutron stars in massive binary systems. I. Classification and evolution  

Energy Technology Data Exchange (ETDEWEB)

A study of the joint evolution of the normal- and neutron-star components of massive binaries opens with a classification scheme and the analytic expressions to be applied in Paper II for computer simulation of the observable properties of such systems.

1983-03-01

121

Neutron Star Evolution with Internal Energy h'q/>a Dissipation by ...  

Science.gov (United States)

Neutron Star Evolution with Internal Energy h'q/>a. Dissipation by Vortex Creep. N. Shibazaki and F. K. Lamb. University of Illinois at Urbana-Champaign ...

122

Genomic Evidence for the Evolution of Streptococcus equi: Host Restriction, Increased Virulence, and Genetic Exchange with Human Pathogens  

UK PubMed Central (United Kingdom)

The continued evolution of bacterial pathogens has major implications for both human and animal disease, but the exchange of genetic material between host-restricted pathogens is rarely considered....Full Text Available

2009-03-01

123

Formation and evolution of the protoplanetary disk  

International Nuclear Information System (INIS)

A disk formation model during collapse of the protosolar nebula, yielding a low-mass protoplanetary disk is presented. The following subject areas are covered: (1) circumstellar disks; (2) conditions for the formation of stars with disks; (3) early evolution of the protoplanetary disk; and (4) temperature conditions and the convection in the protoplanetary disk.

1989-01-02

124

Evolution of the nuclear ribosomal DNA intergenic spacer in four species of the Daphnia pulex complex  

UK PubMed Central (United Kingdom)

BackgroundConcerted evolution refers to the pattern in which copies of multigene families show high intraspecific sequence homogeneity but high interspecific sequence diversity....Full Text Available

125

Evolution of macromolecular import pathways in mitochondria, hydrogenosomes and mitosomes  

UK PubMed Central (United Kingdom)

All eukaryotes require mitochondria for survival and growth. The origin of mitochondria can be traced down to a single endosymbiotic event between two probably prokaryotic organisms. Subsequent evolution...Full Text Available

2010-03-12

126

Evolution of Nitrogen Oxide(s) during In Vivo Nitrate Reductase Assay of Soybean Leaves  

UK PubMed Central (United Kingdom)

Studies were conducted to quantitate the evolution of nitrogen oxides (NO(x)) from soybean [Glycine max (L.) Merr.] leaves during in vivo nitrate reductase...Full Text Available

1981-12-01

127

Components of change in the evolution of learning and unlearned preference  

UK PubMed Central (United Kingdom)

Several phenomena in animal learning seem to call for evolutionary explanations, such as patterns of what animals learn and do not learn. While several models consider how evolution should influence...Full Text Available

2009-09-07

128

Adaptations to sexual selection and sexual conflict: insights from experimental evolution and artificial selection  

UK PubMed Central (United Kingdom)

Artificial selection and experimental evolution document natural selection under controlled conditions. Collectively, these techniques are continuing to provide fresh and important insights into the...Full Text Available

2010-08-27

129

A MODEL OF THE SPECTRAL EVOLUTION OF PULSAR WIND NEBULAE  

International Nuclear Information System (INIS)

We study the spectral evolution of pulsar wind nebulae (PWNe) taking into account the energy injected when they are young. We model the evolution of the magnetic field inside a uniformly expanding PWN. Considering time-dependent injection from the pulsar and coolings by radiative and adiabatic losses, we solve the evolution of the particle distribution function. The model is calibrated by fitting the calculated spectrum to the observations of the Crab Nebula at an age of a thousand years. The spectral evolution of the Crab Nebula in our model shows that the flux ratio of TeV #gamma#-rays to X-rays increases with time, which implies that old PWNe are faint in X-rays, but not in TeV #gamma#-rays. The increase of this ratio is because the magnetic field decreases with time and is not because the X-ray emitting particles are cooled more rapidly than the TeV #gamma#-ray emitting particles. Our spectral ...

2010-06-01

130

The CBM potential of the Foothills/Mountain region of Alberta  

Energy Technology Data Exchange (ETDEWEB)

This presentation described the geology of the Kootenay, Gething, Gates, Brazeau and Coalspur Formations in the potential gas-bearing coal zones of the Alberta Foothills/Mountains. The future potential of this region for coalbed methane (CBM) exploitation was discussed, based on available data from drilling activity and the results of a recent coal desorption and adsorption study in the Val d'Or seam of the Coalspur formation. The gas content of the 5 coal zones was evaluated and compared with previous CBM exploration in the area. For evaluation purposes, the coal zones were divided into shallow and deep coal zones. The potential gas content of the shallow coal zones is approximately 31 Tcf of CBM. This is considered an inferred, initial, in-place, CBM resource estimate based on limited data. The gas content of deep zones is approximately 99 Tcf of ...

2006-07-01

131

Regional evaluation of the coalbed-methane potential of the Foothills/Mountains of Alberta, Canada  

Energy Technology Data Exchange (ETDEWEB)

Coal is present in the Alberta Foothills/Mountains in five zones: the Kootenay, Gething, Gates, Brazeau and Coalspur coal zones. For coalbed-methane (CBM) evaluation purposes, they can be divided into shallow (less than 1000 m depth) and deep (greater than 1000 m depth) coal zones. The potential gas content of all shallow coal zones totals about 878x10{sup 9} m{sup 3} (31 Tcf) of CBM, which is considered an inferred, initial, in-place, coalbed-methane resource estimate based on limited data. The limited amount of data on formation testing and measured gas content indicate that the inferred resource is bordering on the speculative category. The gas content of all deep coal zones (deeper than 1000 m) totals 2.8x10{sup 12} m{sup 3} (about 99 Tcf) of in-place coalbed-methane gas. Consequently, the total ultimate coalbed-methane resource could be 3.7x10{sup 12} m{sup 3} (130 Tcf). ...

2006-01-03

132

Regional evaluation of the Coalbed-Methane Potential of the Foothills/Mountains of Alberta. Revision 2  

Energy Technology Data Exchange (ETDEWEB)

This report describes the geology of the following 5 Alberta Foothills/Mountains coal zones: the Kootenay, Gething, Gates, Brazeau and Coalspur coal zones. The coal areas were assessed for gas content and compared with previous coalbed methane (CBM) exploration in the area. The coal zones can be divided into shallow (less than 1000 m depth) and deep (greater than 1000 m depth) coal zones for evaluation purposes. The potential gas content of the shallow coal zones is approximately 31 Tcf of CBM. This is considered an inferred, initial, in-place, CBM resource estimate based on limited data. The gas content of deep zones is approximately 99 Tcf of in-place CBM gas. Therefore, the total ultimate CBM resource is estimated at 130 Tcf. CBM recovery is not usually attempted due to high drilling costs and low permeability. The only CBM production from the Foothills has ...

2002-10-01

133

White dwarf evolution - Cradle-to-grave constraints via pulsation  

International Nuclear Information System (INIS)

White dwarf evolution, particularly in the early phases, is not very strongly constrained by observation. Fortunately, white dwarfs undergo nonradial pulsation in three distinct regions of the H-R diagram. These pulsations provide accurate masses, surface compositional structure and rotation velocities, and help constrain other important physical properties. We demonstrate the application of the tools of stellar seismology to white dwarf evolution using the hot white dwarf star PG 1159-035 and the cool DAV (or ZZ Ceti) stars as examples. From pulsation studies, significant challenges to the theory of white dwarf evolution emerge. 44 refs.

1990-05-28

134

Unveiling the underlying nature of the new class of HMXBs ...  

Science.gov (United States)

Understanding the detailed mechanics of these systems and their place in the general picture of binary star evolution are the dual objectives of this ...

135

Single and binary star evolution  

International Nuclear Information System (INIS)

After presenting a general account of the observed global properties of single stars of low, intermediate, and high mass, together with their theoretical Hertzsprung-Russell diagram evolution, attention is given to the observed properties of various evolved close binaries and to an assessment of the value of comparisons between observation and crude theory in characterizing the physics of mass transfer within interacting binary systems. Detailed consideration is then undertaken of such topics as stellar evolution in globular clusters, interior star changes due to nucleosynthesis and mixing, asymptotic giant branch stars of intermediate mass, the response of white dwarfs in binary systems to mass accretion, and scenarios for binary star evolution tending toward close white dwarf pairs.

136

Scientific reference on the long time evolution of spent fuels; Referentiel scientifique sur l'evolution a long terme des combustibles uses  

Energy Technology Data Exchange (ETDEWEB)

This report is published in the framework of the 1991 French law for the nuclear waste management. The state of the art reported here concerns the long term evolution of spent fuel in the various environmental conditions corresponding to dry storage and geological disposal: closed system, air and water saturated medium. This review is based on the results of the french PRECCI project (Research Program on Long term Evolution of Spent Nuclear Fuel) and on literature data. (authors)

2005-03-15

137

RXTE Catches Morphing Magnetar  

Science.gov (United States)

This exciting new development in neutron star evolution was presented at the Winter 2004 AAS Meeting in Atlantia,Georgia. ...

138

Nuclear astrophysics  

Energy Technology Data Exchange (ETDEWEB)

Four topics in nuclear astrophysics, namely; pulsars, star evolution, nucleosynthesis and solar neutrinos are reviewed through the discussion of the observational data.

1982-09-01

139

Neutron star evolution with internal heating  

Energy Technology Data Exchange (ETDEWEB)

The thermal evolution predicted by current models of the superfluid-crust interaction is noted to differ substantially from the thermal evolution predicted by models without internal heating as well as previous models of heating. Heating rates approaching the maximum predicted by current models enhance the photon luminosity of the star in the neutrino cooling era, and dramatically alter the thermal evolution in the photon cooling era. Standard cooling models are consistent with current pulsar temperature estimates and upper limits, except those for the Vela pulsar, which are lower than predicted. 77 refs.

1989-11-01

142

CHAM_CLOUD_3 - HEASARC  

Science.gov (United States)

Main purpose of mapping observations of the cloud is to make clear the mechanism of star formation and star evolution. Scientific objectives are summarized ...

143

Achieving the Goals and Objectives of the 2008 - Astrobiology - NASA  

Science.gov (United States)

... the cinder-like planets in orbit around pulsars, the remnants of massive star evolution) to worlds that are more reassuringly familiar. ...

144

Formation and Evolution of Bulges  

CERN Document Server

After presenting three ways of defining a bulge component in disc galaxies, we introduce the various types of bulges, namely the classical bulges, the boxy/peanut bulges and the disc-like bulges. We then discuss three specific topics linked to bulge formation and evolution, namely the coupled time evolution of the bar, buckling and peanut strengths; the effect of velocity anisotropy on peanut formation; and bulge formation via bar destruction.

2007-01-01

145

Delta Scuti stars and stellar evolution  

International Nuclear Information System (INIS)

Recent developments in the knowledge of Delta Scuti stars in relation to stellar evolution are reviewed. The stability of periods and amplitudes is examined, and a working hypothesis suggested. Furthermore, the systematics of the observed long-term period changes are compared with the computed evolutionary tracks, suggesting a severe disagreement for the evolved stars if the period changes are caused by radius changes resulting from stellar evolution. 30 refs.

1990-05-28

146

X-ray zone plate fabrication using a focused ion beam  

Energy Technology Data Exchange (ETDEWEB)

An x-ray zone plate was fabricated using the novel approach of focused ion beam (FIB) milling. The FIB technique was developed in recent years, it has been successfully used for transmission electron microscopy (TEM) sample preparation, lithographic mask repair, and failure analysis of semiconductor devices. During FIB milling, material is removed by the physical sputtering action of ion bombardment. The sputter yield is high enough to remove a substantial amount of material, therefore FIB can perform a direct patterning with submicron accuracy. The authors succeeded in fabricating an x-ray phase zone plate using the Micrion 9500HT FIB station, which has a 50 kV Ga{sup +} column. Circular Fresnel zones were milled in a 1.0-{micro}m-thick TaSiN film deposited on a silicon wafer. The outermost zone width of the zone plate is 170 nm at a radius of 60 {micro}m. An achieved aspect ratio ...

2000-08-16

147

Reflectance and petrology of a burning bituminous coal seam  

Energy Technology Data Exchange (ETDEWEB)

Samples from a burning bituminous coal seam from Coalspur, Alberta, were studied by reflected light microscopy. Two zones - namely oxidation- combustion and distillation - were detected in the seam. Near the surface, the oxidation zone contained chars showing cracks and oxidation rims. The cracks were filled with fluorescing hydrocarbon material formed by thermal cracking of coal macerals. The chars in the deeper part of the oxidation zone had a carbonized matrix and burnt rims. The distillation zone covered most of the coal seam. Chars were mostly in the precarbonization stage, except those immediately below the combustion zone or near the base of the seam. Precarbonized chars contained pyrolytic carbon in some horizons. The distilled chars were formed by heat generated by combustion at the top of the seam and also by heat transfer from an underlying burning seam through an ...

1987-08-01

148

Stratigraphy and sedimentary environment of the Coalspur Formation  

Energy Technology Data Exchange (ETDEWEB)

The Coalspur Formation is a continental succession of interbedded mudstone, siltstone and fine grained sandstone with subordinate coarser grained sandstone layers and channel lag deposits. Chert-pebble conglomerate (the Entrance conglomerate) occurs at the base of the formation, and coal beds interbedded with coaly shale and numerous thin bentonites occur in the upper part of the formation. An economically significant amount of high-quality thermal coal occurs within the upper, Paleocene part of the formation named the Coalspur coal zone. Coal from this zone, also known as the Coal Valley coal zone is being exploited in the Coal Valley Mine. 17 refs., 4 figs.

1990-01-01

149

Crossing Zones in the Vestibulocerebellum: A Commentary  

British Library Electronic Table of Contents (United Kingdom)

The contention of this commentary, focused on the vestibulocerebellum (particularly the flocculus), is that the great importance for our understanding of cerebellar organization in terms of climbing fiber zones, begun years ago by Voogd [1969, 2011] and Oscarsson [1969], needs to be matched by coming more to grips with the other fundamental geometrical organization of the cerebellum, the parallel fibers. The central issue is the selection of those parallel fiber signals to be transformed into Purkinje cell activity in the different zones. At present, in comparison to our knowledge of vestibulocerebellar climbing fiber inputs, the deficiencies in our knowledge of the zonal anatomy and physiology of vestibulocerebellar mossy fibers and granule cells are glaring. The recent emphasis on molecu...

2011-01-01

150

An intracranial aspergilloma with low signal on T2-weighted images corresponding to iron accumulation  

Energy Technology Data Exchange (ETDEWEB)

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

2001-07-01

151

Nuclear reaction rates and opacity in massive star evolution calculations  

International Nuclear Information System (INIS)

Nuclear reaction rates and opacity are important parameters in stellar evolution. The input physics in a stellar evolution code determines the main theoretical characteristics of the stellar structure, evolution and nucleosynthesis of a star. For different input physics, in this work we calculate stellar evolution models of very massive first stars during the hydrogen and helium burning phases. We have considered 100 and 200M_sun galactic and pregalactic stars with metallicity Z = 10"-"6 and 10"9, respectively. The results show important differences from old to new formulations for the opacity and nuclear reaction rates, in particular the evolutionary tracks are significantly affected, that indicates the importance of using up to date and reliable input physics. The triple alpha reaction activates sooner for pregalactic than for galactic stars.

2010-07-01

152

Effective Population Size Is Positively Correlated with Levels of Adaptive Divergence among Annual Sunflowers  

British Library Electronic Table of Contents (United Kingdom)

The role of adaptation in the divergence of lineages has long been a central question in evolutionary biology, and as multilocus sequence data sets have become available for a wide range of taxa, empirical estimates of levels of adaptive molecular evolution are increasingly common. Estimates vary widely among taxa, with high levels of adaptive evolution in Drosophila, bacteria, and viruses but very little evidence of widespread adaptive evolution in hominids. Although estimates in plants are more limited, some recent work has suggested that rates of adaptive evolution in a range of plant taxa are surprisingly low and that there is little association between adaptive evolution and effective population size in contrast to patterns seen in other taxa. Here, we analyze data from 35 loci for si...

2011-01-01

153

Tomographic measurements of carbon monoxide temperature and concentration in a Bunsen flame using diode laser absorption  

Energy Technology Data Exchange (ETDEWEB)

Temperature and concentration profiles of CO in a laminar, axisymmetric, premixed methane-air Bunsen flame are measured using line-of-sight diode laser absorption spectroscopy and computer tomographic (CT) reconstruction. Absorption spectra for P(20) (v=2<-1) and P(27) (v=1<-0) vibrotational transitions of CO were measured at 21 evenly spaced positions over a 1.33 cm span for a 1.3 cm radius flame. CT reconstruction algorithm was based on Fourier convolution. The tomographically reconstructed normalized transmission profiles derived from absorption spectra, in conjunction with a quantum mechanical model for vibrotational behavior of CO, yielded both temperature and concentration profiles. The Bunsen flame had 3 distinct zones: an inner rich-premixed flame zone, an outer non-premixed flame zone and an unburnt core region. The reconstructed temperature profile showed that the core region temperature was close to ambient ...

1993-12-01

157

Smooth Particle Hydrodynamics for Surf Zone Waves  

Science.gov (United States)

... Zou, S. and RA Dalrymple, ``Coastal Sediment Transport Simulation by Smoothed Particle Hydrodynamics,'' Journal of Waterways, Ports, Coastal ...

2011-05-15

158

Short Course on Implementation of Zone Technology in the ...  

Science.gov (United States)

... In a first-of-its-kind operation, Lisnave recently converted Latvian Shipping Company's 20,000 dwt products tanker Dzintari into a full Class 3 ...

1996-04-01

159

Recurrence Intervals for Great Earthquakes of the Past 3,500 Years at Northeastern Willapa Bay, Washington  

Science.gov (United States)

Plate-boundary earthquakes have occurred repeatedly in the past several thousand years at the Cascadia subduction zone, where they are widely recorded ... ...

160

Rapid and cost-effective assessment of connectivity among assemblages of Choerodon rubescens (Labridae), using laser ablation ICP-MS of sagittal otoliths  

British Library Electronic Table of Contents (United Kingdom)

A rapid and cost-effective assessment was required to provide advice to management on the connectivity between juvenile and adult life cycle stages of Baldchin Groper Choerodon rubescens, a labrid endemic to the west coast of Australia, which has high social value, but relatively low commercial fishery importance. To minimise costs we used laser ablation ICP-MS to analyse levels of a small suite of elements (Ca, Mg, Mn, Cu, Zn, Sr, Rb, Ba and Pb) at the margin (adult phase) and core (juvenile phase) of the same otoliths of adult C. rubescens, collected at ten locations in five management zones. The elemental composition of both otolith margins and cores differed significantly among management zones and in some cases among locations within zones. Similarity of the pattern of among-zone elem...

2011-01-01

161

On the solid-fluid transition zone in welding analysis  

Energy Technology Data Exchange (ETDEWEB)

Equilibrium and energy equations have been developed in describing the solid-fluid transition zone during the melting and solidification of the binary alloys. Due to the existence of the transition region exhibited both solid and fluid phases at the same material point from continuum point of view, mixture theory was utilized to analyze the region. Unlike the Stefan problem, the latent heat due to the phase change appears as a source term in the heat equation. The molten fluid is treated as a thermoviscous and incompressible fluid, whereas the solid is thermoviscoplastic described by the Bodner-Partom/Walker type of constitutive equations. Thermal mechanical behaviors of the solid and the fluid phases are determined separately because of insignificant mechanical interactions between them. Volume fractions of the phases are obtained according to the equilibrium phase diagram. The simulation process of the transition zone and the welding process ...

1993-01-01

162

News - NASA Earth Observatory  

Science.gov (United States)

Satellite Observations of the Southeast Pacific Intertropical Convergence Zone During 1993-1998, Halpern, D.; Hung, C.-W., Journal of Geophysical Research ? ...

163

Neural Tissues from the Implanted Stem Cells  

International Science & Technology Center (ISTC)

Morphological, Electrophysiological and Behavioral Investigations of the Nervous Tissue Developed from the Embryonic Matrix Zone Cells of the Dorsolateral Walls of Lateral Ventricles, Implanted into the Lesioned Regions of the Adult Rat's Brain

165

Feasibility investigations of growing and characterizing gallium arsenide crystals in ribbon form. Quarterly progress report 1 Jan-31 Mar 1975  

International Nuclear Information System (INIS)

The feasibility of continuous production of gallium arsenide ribbon single crystals, by passage of a molten zone through boron-oxide encapsulated GaAs feedstock, is being investigated. Polycrystalline GaAs ribbons have been grown in graphite boats by passage of a wide zone through B2O3-encapsulated feed-stock, confined by a quartz cover plate. Failure to remove the encapsulant above its glass transition temperature, however, resulted in cracking of the ribbons on cooling to room temperature. In order to study the crucial zone melting step in isolation from the encapsulation steps of the continuous process, a constrained-zone melting apparatus has been constructed in which the boron oxide serves only as a sealant to suppress arsenic vaporization. Large grained polycrystalline samples have been produced with this apparatus.

167

Effects of Yttrium Microalloying on the Epitaxial Grain Growth ...  

Science.gov (United States)

... Accession Number : ADA137272. Title : Effects of Yttrium Microalloying on the Epitaxial Grain Growth in Ti-6Al-4V Weld Fusion Zones. ...

1983-10-01

168

Dutch distribution zones of stable iodine tablets based on atmospheric dispersion modelling of accidental releases from nuclear power plants.  

Science.gov (United States)

Rapid administration of stable iodine is essential for the saturation and subsequent protection of the thyroid gland against the potential harm caused by radioiodines. This paper proposes the Dutch risk analysis that uses an atmospheric dispersion model to calculate the size of the zones around nuclear power plants where radiological thyroid doses for children might be sufficiently high to warrant iodine administration. Dose calculations for possible releases from the nuclear power plants of Borssele (The Netherlands), Doel (Belgium) and Emsland (Germany) are based on two scenarios in combination with a 1-y set of authentic, high-resolution meteorological data. The dimensions of the circular zones were defined for each nuclear power plant. In these zones, with a radius up to 50 km, distribution of stable iodine tablets is advised. PMID:20332130

2010-03-23

169

Dutch distribution zones of stable iodine tablets based on atmospheric dispersion modelling of accidental releases from nuclear power plants  

British Library Electronic Table of Contents (United Kingdom)

Rapid administration of stable iodine is essential for the saturation and subsequent protection of the thyroid gland against the potential harm caused by radioiodines. This paper proposes the Dutch risk analysis that uses an atmospheric dispersion model to calculate the size of the zones around nuclear power plants where radiological thyroid doses for children might be sufficiently high to warrant iodine administration. Dose calculations for possible releases from the nuclear power plants of Borssele (The Netherlands), Doel (Belgium) and Emsland (Germany) are based on two scenarios in combination with a 1-y set of authentic, high-resolution meteorological data. The dimensions of the circular zones were defined for each nuclear power plant. In these zones, with a radius up to 50 km, distrib...

2010-01-01

170

Characterization of cry Genes in a Mexican Bacillus thuringiensis Strain Collection  

UK PubMed Central (United Kingdom)

Mexico is located in a transition zone between the Nearctic and Neotropical biogeographical regions and contains a rich and unique biodiversity. A total of 496 Bacillus thuringiensis...Full Text Available

1998-12-01

171

Vacuolar/Extravacuolar Distribution of Aminopeptidases in Giant Alga Chara australis and Partial Purification of One Such Enzyme 1  

Science.gov (United States)

The presence of two major aminopeptidases (aminopeptidases I and II) in the giant alga Chara australis was shown using polyacrylamide gel electrophoresis. Partially purified aminopeptidase I had a molecular weight of about 120,000, hydrolyzed both leucine-?-naphthylamide (pH optimum 6.0) and alanine-?-naphthylamide (pH optimum 7.5), and was located both inside and outside the vacuole. Aminopeptidase I was inhibited by p-chloromercuribenzoic acid, iodoacetic acid, 1,10-phenanthroline, and N-tosyl-l-phenylalanine chloromethyl ketone. Aminopeptidase II hydrolyzed alanine-?-naphthylamide but not leucine-?-naphthylamide and was located only outside the vacuole.ImagesFig. 1Fig. 2Fig. 4Fig. 5

1987-01-01

172

Studies of human mutation rates  

Energy Technology Data Exchange (ETDEWEB)

November 1989, marked the beginning of a new three-year cycle of DOE grant support, in connection with which the program underwent a major reorganization. This document presents the progress on the three objectives of the present program which are: to isolate by the technique of two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), proteins of special interest because of the relative mutability of the corresponding gene, establish the identity of the protein, and, for selected proteins, move to a characterization of the corresponding gene; to develop a more efficient approach, based on 2-D PAGE, for the detection of variants in DNA, with special reference to the identification of mutations in the parents of the individual whose DNA is being examined; and, to continue an effective interface with the genetic studies on the children of atomic bomb survivors in Japan, with reference to both the planning and implementation of new studies at the molecular level.

1990-01-01

173

Structure-activity relationships of anthraquinone derivatives derived from bromaminic acid as inhibitors of ectonucleoside triphosphate diphosphohydrolases (E-NTPDases)  

British Library Electronic Table of Contents (United Kingdom)

Reactive blue 2 (RB-2) had been characterized as a relatively potent ectonucleoside triphosphate diphosphohydrolase (E-NTPDase) inhibitor with some selectivity for NTPDase3. In search for the pharmacophore and to analyze structure-activity relationships we synthesized a series of truncated derivatives and analogs of RB-2, including 1-amino-2-sulfo-4-ar(alk)ylaminoanthraquinones, 1-amino-2-methyl-4-arylaminoanthraquinones, 1-amino-4-bromoanthraquinone 2-sulfonic acid esters and sulfonamides, and bis-(1-amino-4-bromoanthraquinone) sulfonamides, and investigated them in preparations of rat NTPDase1, 2, and 3 using a capillary electrophoresis assay. Several 1-amino-2-sulfo-4-ar(alk)ylaminoanthraquinone derivatives inhibited E-NTPDases in a concentration-dependent manner. The 2-sulfonate group ...

2009-01-01

174

Proteomic analysis of sericin in Bombyx mori cocoons  

British Library Electronic Table of Contents (United Kingdom)

Cocoon sericin plays an important role in the reeling of silk and serves as a valuable biomaterial in the field of biomedicine, skincare, and food industries; however, knowledge about cocoon sericin proteins has been limited. For a comprehensive study on sericin, cocoons of eight varieties of silkworm of different geographic origin and with varied cocoon color were analyzed utilizing proteomics and bioinformatics approaches. The electrophoresis pattern demonstrated some common protein bands for all silkworm varieties and distinctive protein bands for some of those examined in the present study. The Ser2 protein, a new Ser3 protein, and four other novel sericin proteins were identified in cocoons for the first time. Products of both Ser1 and Ser3 genes appear to be ubiquitous in the cocoon ...

2011-01-01

175

Programmed cell death during pigment gland formation in Gossypium hirsutum leaves  

British Library Electronic Table of Contents (United Kingdom)

Abstract Ultrastructural studies have shown that the formation of pigment glands in Gossypium hirsutum L. leaves is a lysigenous process, originating from a cluster of cells in the ground meristem. Various techniques were used here to investigate whether programmed cell death (PCD) plays a critical role in this developmental process. Nuclei of internal cells in the pigment gland-forming tissue were TUNEL-positive and DAPI-negative, suggesting that DNA cleavage is an early event and complete DNA degradation is a late event. Smeared bands and a lack of laddering after gel electrophoresis indicate that DNA cleavage is random. Ultrastructurally, secretory cells in the pigment glands become distorted, nuclei are densely stained, and chromosomes become condensed until completely degraded at late...

2010-01-01

176

Nitrilotriacetate complex of univalent astatine  

Energy Technology Data Exchange (ETDEWEB)

Formation of the complex of the univalent astatine cation with nitrilotriacetic acid (AtL)[sup 2-] and its stability constant (lgK[sub 1]=8.97(4), 25degC, [mu]=0.1) have been found experimentally for the first time. The complex is stable in perchlorate solutions in presence of 5 . 10[sup -3] mol . l[sup -1] of the oxidizer Na[sub 2]S[sub 2]O[sub 8] in the interval 4[<=]pH[<=]8.5. The complex is supposed to be destroyed in weak alkaline solutions by reduction of astatine to astatide. The deprotonation constant of hypoastatic acid pK[sub dp]=5.23(9) was found to be lower than determined previously. The investigation was carried out by the method of ion electrophoresis in free electrolyte solutions. (orig.).

1992-01-01

177

Nitrilotriacetate complex of univalent astatine  

International Nuclear Information System (INIS)

Formation of the complex of the univalent astatine cation with nitrilotriacetic acid (AtL)"2"- and its stability constant (lgK_1=8.97(4), 25degC, #mu#=0.1) have been found experimentally for the first time. The complex is stable in perchlorate solutions in presence of 5 . 10"-"3 mol . l"-"1 of the oxidizer Na_2S_2O_8 in the interval 4#<=#pH#<=#8.5. The complex is supposed to be destroyed in weak alkaline solutions by reduction of astatine to astatide. The deprotonation constant of hypoastatic acid pK_d_p=5.23(9) was found to be lower than determined previously. The investigation was carried out by the method of ion electrophoresis in free electrolyte solutions. (orig.).

178

Methanogen community structure in the rumens of farmed sheep, cattle and red deer fed different diets  

British Library Electronic Table of Contents (United Kingdom)

Abstract Development of inhibitors and vaccines that mitigate rumen-derived methane by targeting methanogens relies on knowledge of the methanogens present. We investigated the composition of archaeal communities in the rumens of farmed sheep (Ovis aries), cattle (Bos taurus) and red deer (Cervus elaphus) using denaturing gradient gel electrophoresis (DGGE) to generate fingerprints of archaeal 16S rRNA genes. The total archaeal communities were relatively constant across species and diets, and were less variable and less diverse than bacterial communities. There were diet- and ruminant-species-based differences in archaeal community structure, but the same dominant archaea were present in all rumens. These were members of three coherent clades: species related to Methanobrevibacter ruminan...

2011-01-01

179

Malignant transformation of diploid human fibroblasts by transfection of oncogenes  

Energy Technology Data Exchange (ETDEWEB)

This document consist of brief reports prepared by postdoctoral students supported by the project, each describing his accomplishments under the grant. Topics include (1) Malignant Transformation of MSU-1. 1 Cells by Gamma Radiation, (2) Correlation between Levels of ras Expression and Presence of Transformed Phenotypes Including Tumorigenicity, Using a Modulatable Promoter, (3) Relation between Specific rad Oncogene Expression, (4) Correlation of Genetic Changes in Fibroblastic Tumors with Malignancies, (5)Transformation of MSU-1.1 Cells by sis Oncogene, (6) Malignant Transformation of MSU-1.0 Cells, (7) Correlation of Urokinase Plasminogen Activation (mu-PA) with Malignant Phenotype, (8)Two Dimensional Gel Electrophoresis Studies of the Proteins of the Major Cell Strains of the MSU-1 Family of Cells, and (9) Correlation between Proteinase Activity Levels and Malignancy.

1992-01-01

180

Improvement of reproducibility and sensitivity of CE analysis by using the capillary coated dynamically with carboxymethyl chitosan  

British Library Electronic Table of Contents (United Kingdom)

Analysis reproducibility and detection sensitivity of capillary electrophoresis (CE) are often questioned by applied scientists, which has hindered its application as a routine method. To address these issues, a simple, precise, and reproducible dynamic coating method was developed by applying carboxymethyl chitosan (CMC) dynamic coating on fused silica capillary. The proposed coating was accomplished by simply rinsing the capillary with CMC solution for 1?min in between runs, with no regeneration procedure or buffer additives needed. Electroosmotic flow could be well controlled by adjusting the pH of background electrolyte, and the adsorption of analytes onto the capillary inner wall was effectively eliminated. The main parameters of the coating condition were optimized, and extensive app...

2011-01-01

181

Functional adaptation of microbial communities from jet fuel-contaminated soil under bioremediation treatment: simulation of pollutant rebound  

British Library Electronic Table of Contents (United Kingdom)

Abstract To investigate the link between the functionality and the diversity of microbial communities under strong selective pressure from pollutants, two types of mesocosms that simulate natural attenuation and phytoremediation were generated using soil from a site highly contaminated with jet fuel and under air-sparging treatment. An increase in the petroleum hydrocarbon concentration from 4900 to 18-500-mg-kg-1-dw soil simulated a pollutant rebound (postremediation pollutant reversal due to residual contamination). Analysis of soil bacterial communities by denaturing gradient gel electrophoresis of PCR-amplified 16S rRNA gene fragments showed stronger changes and selection for a phylogenetically diverse microbial population in the mesocosms with pollutant-tolerant willow trees. Enumerat...

2011-01-01

182

From Egg to Crystal: A Practical on Purification, Characterization, and Crystallization of Lysozyme for Bachelor Students  

Science.gov (United States)

A practical hands-on course encompassing enzyme purification, biochemical characterization, and crystallization that completed the course work of 350 second-year bachelor students enrolled in molecular biology/biochemistry was given at the Universite Louis Pasteur of Strasbourg (France). The experimental part of the practical dealt entirely with the model protein lysozyme isolated from hen egg-white. It was designed as a research project to give students the possibility to practice biochemical methods such as chromatography, electrophoresis, and spectrophotometry. It also included enzyme activity assay and protein crystal growth that are usually taught in master-level courses. The organization of the practical work and the related experimental procedures are described and discussed.

2007-07-01

183

Evaluation of a commercial MRSA assay when multiple MRSA strains are causing epidemics  

British Library Electronic Table of Contents (United Kingdom)

Rapid and reliable diagnostic methods are needed to control methicillin-resistant Staphylococcus aureus (MRSA) transmission. We studied the BD GeneOhm? MRSA Assay which is based on one specific amplification product at the junction of the right extremity sequence of the staphylococcal cassette chromosome mec (SCCmec) and the chromosomal sequence of orfX of S. aureus. The test was applied on 95 clinical isolates in Finland: 83% were positive. The isolates giving negative results represented several pulsed-field gel electrophoresis (PFGE) types and harboured SCCmec types IV, V, VI or were new types with different combinations of ccr genes.

2009-01-01

184

Electron Capture Dissociation Implementation Progress in Fourier Transform Ion Cyclotron Resonance Mass Spectrometry  

British Library Electronic Table of Contents (United Kingdom)

Successful electron capture dissociation (ECD) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) applications to peptide and protein structural analysis have been enabled by constant progress in implementation of improved electron injection techniques. The rate of ECD product ion formation has been increased to match the liquid chromatography and capillary electrophoresis timescales, and ECD has been combined with infrared multiphoton dissociation in a single experimental configuration to provide simultaneous irradiation, fast switching between the two techniques, and good spatial overlap between ion, photon, and electron beams. Here we begin by describing advantages and disadvantages of the various existing electron injection techniques for ECD in FT-ICR MS. We next ...

2008-01-01

185

Effect of season on contractile and metabolic properties of desert camel muscle (Camelus dromedarius)  

British Library Electronic Table of Contents (United Kingdom)

Thirty fattened one humped desert camels were used to examine the effect of season on contractile and metabolic properties of Longissimus thoracis (LT) muscle. Ten camels were slaughtered according to seasons of the year (winter, summer and autumn). Season significantly influenced muscle chemical composition, ultimate pH (pHu) and color. Activities of metabolic enzymes were higher during autumn season compared to summer and winter for phosphofructokinase (+64% compared to both seasons) and for isocitrate dehydrogenase (+35% and +145% in autumn vs. summer and winter, respectively). Quantification of muscle myosin heavy chain isoforms by SDS-PAGE electrophoresis showed only presence of type I and type IIa MyHC in camel muscle and indicated high proportion in winter for type I and in autumn f...

2012-01-01

186

Cholera toxin can catalyze ADP-ribosylation of cytoskeletal proteins  

International Nuclear Information System (INIS)

Cholera toxin catalyzes transfer of radiolabel from ["3"2P]NAD"+ to several peptides in particulate preparations of human foreskin fibroblasts. Resolution of these peptides by two-dimensional gel electrophoresis allowed identification of two peptides of M/sub r/ = 42,000 and 52,000 as peptide subunits of a regulatory component of adenylate cyclase. The radiolabeling of another group of peptides (M/sub r/ = 50,000 to 65,000) suggested that cholera toxin could catalyze ADP-ribosylation of cytoskeletal proteins. This suggestion was confirmed by showing that incubation with cholera toxin and ["3"2P]NAD"+ caused radiolabeling of purified microtubule and intermediate filament proteins.

1981-01-01

187

A protocol for the evaluation of genotoxicity in bile of carp (Cyprinus carpio) exposed to lake water treated with different disinfectants  

British Library Electronic Table of Contents (United Kingdom)

A sensitive and rapid method to evaluate toxic and genotoxic properties of drinking water supplied from Lake Trasimeno (Umbria, Central Italy) was worked out analysing bile in Cyprinus carpio exposed for 20d to lake water treated with 3 different disinfectants, sodium hypochlorite (NaClO), chlorine dioxide (ClO2) and peracetic acid (PAA). Fish were sacrificed at 0, 10 and 20d in order to investigate the time course of these endpoints. An aliquot of bile samples was fractionated by adsorption on C18 silica cartridges and the genotoxic potential of whole bile and of bile fractions was evaluated by the single-cell microgel-electrophoresis (comet) assay on human colonic adenocarcinoma cells (Caco-2). Bile (both whole and fractionated) from specimens exposed to the three disinfectants always sh...

2011-01-01

188

A miniaturized spatial temperature gradient capillary electrophoresis system with radiative heating and automated sample introduction for DNA mutation detection  

British Library Electronic Table of Contents (United Kingdom)

Abstract A miniaturized spatial temperature gradient CE system with automated sample introduction for DNA mutation detection was established. Continuous electrokinetic sample injection was achieved by combining an automated slotted vial array sample introduction device to the spatial temperature gradient CE system. The temperature gradient was produced by a radiative heating system with a single graphite block heater, and the stability of the temperature gradient was investigated. The temperature variation of each measure point was 0.12 0.21% RSD (n=7) within 6 h. A 14 cm Teflon AF coated silica capillary was used both as the separation channel and as the liquid core waveguide tube of fluorescence signal. Under a temperature gradient from 54.8 to 59.5 C, a low range control mutation standa...

2010-01-01

189

211At-Rh(16-S4-diol) as a starting complex for preparing an astatine-labeled radiopharmaceutical  

British Library Electronic Table of Contents (United Kingdom)

A new procedure for preparing an 211At-labeled radiopharmaceutical is suggested. The 211At? anion forms a strong bond with the Rh3+ cation incorporated in the complex with a thiother ligand, 1,5,9,13-tetrathiacyclohexadecane-3,11-diol (16-S4-diol). The reaction conditions are optimized with 131I as astatine analog. The complexes are studied by paper electrophoresis, ion exchange, and thin-layer chromatography. The kinetics of the addition of the 131I? anion to Rh(16-S4-diol) and the dependence of the yield of the forming complex 131I-Rh(16-S4-diol) on the temperature, solution acidity, and reactant concentrations are examined. Taking into account the results obtained, the complex 211At-Rh(16-S4-diol) is prepared by adding astatide (211 At?) to equivalent amounts of RhCl3 and the tetrathioe...

2008-01-01

190

Wind energy mapping of coastal zones by synthetic aperture radar (SAR) for siting potential windmill locations  

Energy Technology Data Exchange (ETDEWEB)

The authors propose using synthetic aperture radar(SAR) for wind energy mapping of coastal zones. The SAR equipment is located on the European Space Agency ERS-1 and 2 and the RADARSAT satellites. Examples of wind energy maps and evaluations of their applications are given for the Norwegian west coast.

2000-07-01

191

Stabilization of Plutonium in Subsursface Environments via Microbial Reduction and Biofilm Formation  

Energy Technology Data Exchange (ETDEWEB)

Our work is towards mechanistically understanding interactions of unsaturated bacterial biofilms and their extracellular polymeric substances (EPS) with actinide metals and metal surrogates under vadose zone conditions. Because metal contaminants in the vadose zone co-occur with organic pollutants, some of our work has included experiments with organic pollutants.

2005-06-01

192

Slurry intake device  

Energy Technology Data Exchange (ETDEWEB)

A slurry intake device is proposed which contains an inlet sleeve, housing with grating installed with the discharge end in the zone of the slurry outlet, and hinged deflector. In order to conserve the clay mud, it is equipped with a tie rod and two-arm lever which is kinematically linked to the deflector and the grating. It is installed by hinges in relation to the housing and the latter is attached by hinges to the inlet sleeve. The deflector is arranged in the zone of slurry outlet. The device is distinguished by the fact that the deflector is equipped with a cantilever on which a fixable weight is attached.

1982-01-01

193

Simulations of Groundwater Flow and Radionuclide Transport in the Vadose and Saturated Zones beneath Area G, Los Alamos National Laboratory  

Energy Technology Data Exchange (ETDEWEB)

Numerical simulations are used to predict the migration of radionuclides from the disposal units at Material Disposal Area G through the vadose zone and into the main aquifer in support of a radiological performance assessment and composite analysis for the site. The calculations are performed with the finite element code, FEHM. The transport of nuclides through the vadose zone is computed using a three-dimensional model that describes the complex mesa top geology of the site. The model incorporates the positions and inventories of thirty-four disposal pits and four shaft fields located at Area G as well as those of proposed future pits and shafts. Only three nuclides, C-14, Tc-99, and I-129, proved to be of concern for the groundwater pathway over a 10,000-year period. The spatial and temporal flux of these three nuclides from the vadose zone is applied as a source term for the three-dimensional saturated ...

1999-07-01

194

Regional evaluation of the coal-bed methane potential of the foothills/mountains of Alberta  

Energy Technology Data Exchange (ETDEWEB)

The coal bed methane (CBM) potential of five coal zones (the Kootenay, Gething, Gates, Brazeau, and Coalspur) in the Alberta foothills and mountains is re-evaluated. For evaluation, the coal zones are divided into shallow (200 to 2500 m depth) and deep (over 2500 m depth). The total gas content is estimated. Recommendations on how to obtain more reliable resource data and about producibility are included. 41 refs., 12 figs., 3 tabs., 2 apps.

2001-09-01

195

Poster 20. Analysis of chemical environment conditions in boiling zones  

International Nuclear Information System (INIS)

Boiling phenomenon is responsible for impurities concentration in the liquid phase and then can involve chemically aggressive conditions. This paper presents the methodology developed by NOVATOME to know the water quality conditions in the boiling zone and under deposits, in order to improve corrosion tests and materials reliability and safety. Calculations show that concentration of chloride and sodium hydroxide for example can reach significant levels which may lead to corrosion risks. (author).

196

On concentration of soluble impurities in water volume of the PGV-1000 steam generator  

International Nuclear Information System (INIS)

Peculiarities of design of the PGV-1000 horizontal steam generator affecting soluble impurity distribution in its water volume are considered in brief. The results of estimating sodium distribution in different zones of the steam generator are presented. The conclusion is made on the necessity of arrangement of representative measurements of sodium and chloride content in water volume of the steam generator, particularly, in the hot bottom zone for optimization of blow-through flowsheet and its regulations.

1987-01-01

197

Dual focal point electro-optic lens with a Fresnel-zone plate on a PLZT ceramic.  

Science.gov (United States)

A new dual focal point electro-optic lens that is switchable to focusing and unfocusing is proposed and successfully demonstrated. This electro-optic lens is constructed by coating transparent fine electrodes in the Fresnel-zone plate onto a PLZT ceramic plate. Its focal length changes from 1.25 m to infinity binary at 515 nm with the external voltage of 210 V. PMID:20725208

1992-05-20

198

Behavior and impact assessment of heavy metals in estuarine and coastal zones  

Energy Technology Data Exchange (ETDEWEB)

Contents include: introduction; river systems; physical processes; chemical processes; estuaries and coastal zone; introduction; physical processes; chemical processes; the role of sediments; introduction; the anoxic layer; major-element chemistry; minor-element chemistry; the oxic-anoxic interface; assessment; introduction; analysis of sediments; modelling.

1987-01-01

199

An instrument for measuring spatial and time characteristics of sea agitation in coastal zones  

Energy Technology Data Exchange (ETDEWEB)

Resistive analogous meters for spatial and time characteristics in ocean agitation are most often used in practical oceanography in coastal zones but are based on bridge circuits determined to have shortcomings in their linearity range. This shortcoming is eliminated in the circuit of an instrument developed in an oceanographic laboratory (IMIO, Vana). Principle and block circuits are indicated, and static calibration curves are presented as are the correlative functions in the frequency spectrums obtained with the help of sea agitation recorded at a fixed point and at a depth of 6 meters.

1981-01-01

200

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

Energy Technology Data Exchange (ETDEWEB)

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

1998-12-31

201

Source tracking of Escherichia coli by 16S-23S intergenic spacer region denaturing gradient gel electrophoresis (DGGE) of the rrnB ribosomal operon.  

Science.gov (United States)

This research validates a novel approach for source tracking based on denaturing gradient gel electrophoresis (DGGE) analysis of DNA extracted from Escherichia coli isolates. Escherichia coli from different animal sources and from river samples upstream from, at, and downstream of a combined sewer overflow were subjected to DGGE to determine sequence variations within the 16S-23S intergenic spacer region (ISR) of the rrnB ribosomal operon. The ISR was analyzed to determine if E. coli isolates from various animal sources could be differentiated from each other. DNA isolated from the E. coli animal sources was PCR amplified to isolate the rrnB operon. To prevent amplification of all 7 E. coli ribosomal operons by PCR amplification using universal primers, sequence-specific primers were utilized for the rrnB operon. Another primer set was then used to prepare samples of the 16S-23S ISR for DGGE. Comparison of PCR-DGGE results between human and animal sources revealed ...

2007-10-01

202

Detection by cationized /sup 125/I-cytochrome C of proteoglycans (PG) transferred to nylon  

Energy Technology Data Exchange (ETDEWEB)

Cytochrome c, labeled with /sup 125/I, has been used by us for staining glycosaminoglycans (GAG) separated by electrophoresis on cellulose acetate strips. As GAG between 1-10 ng could be quantified by autoradiography and densitometry, the reagent is approximately 100-fold more sensitive than currently used non-radiolabeled stains. The authors extend now the use of radiolabeled cytochrome c to the quantification of PG transblotted to solid supports subsequent to separation on polyacrylamine slab gels. Dot blotting used for exploring optimal conditions for detecting PG indicated that because of low background positively charged Nylon 66 was superior to nitrocellulose. Increasing the positive charge of the staining reagent by cationization decreased background radiation even further so that 1 ng PG could be seen readily after 5 hrs of autoradiography. Use of cationized /sup 125/I-cytochrome c has been made in detecting PG of bovine fetal epiphyseal cartilage (> 1 x ...

1986-05-01

203

Trishear fault-propagation folding  

Energy Technology Data Exchange (ETDEWEB)

Previous models of fault-propagation folding used kink-band geometries to approximate folding in front of propagating thrusts. However, kink-band kinematics cannot replicate the curved fold surfaces and complex strain patterns innatural and experimental fault-propagation folds, which also occur in front of steeper reverse and normal faults. Fault-propagation fold hinges tighten and converge downward, forming a triangular zone of penetrative deformation focused on the tip of the propagating fault. The downward convergence of deformation in fault-propagation folds can be modeled as triangular shear zones. Trishear, here defined as distributed, strain-compatible shear in a triangular (in profile) shear zone, provides an alternate kinematic model for fault-propagation folds. Trishear is analogous to simple shear in a tabular shear zone except that area balance in a triangular shear zone ...

1991-06-01

204

Relationship between QRS transition zone and the interventricular septum; Using CT scan  

Energy Technology Data Exchange (ETDEWEB)

The relationship between the QRS transition zone of the standard 12-lead ECG and interventricular septum was studied. The position and the angle to the horizontal line of the interventricular septum were evaluated with computed tomography (CT) and compared to the QRS transition zone. The subjects were 36 patients with no cardiovascular diseases. The patients were divided into 3 groups according to the position of QRS transition zone: V{sub 1}-V{sub 2} (8 cases), V{sub 3}-V{sub 4} (21 cases), and V{sub 5}-V{sub 6} (7 cases). The interventricular septum on CT was directed to the anterior chest wall between V{sub 3} and V{sub 4} in all 3 groups. The mean value of the interventricular septal angle did not differ from group to group, 52.1deg for V{sub 1}-V{sub 2} group, 49.8deg for V{sub 3}-V{sub 4} group, and 48.2deg for V{sub 5}-V{sub 6}. It was concluded that the direction of the interventricular septum was not one of the ...

1991-11-01

205

Radiation damage and hardening of molybdenum in 29 MeV alpha particle straggling zone  

International Nuclear Information System (INIS)

Technique, allowing to investigate straggling zone (full braking) from high-energy charged particles in detail, is described. Experimental results on investigation of efective structure, created in polycrystalline molybdenum (99.97%) within 29 MeV alpha-particles straggling zone for fluences from 3.8x10"1"9 up to 3.7x10"2"1 #alpha#/m"2 by methods of microhardness (H_#mu#, X-ray structural analysis (#DELTA#a/a) and transparent electron microscopy (TEM), are presented. It is determined, that for doses from 3.8x10"2"0 #alpha#/m"2 and higher, at #approx#6 MeV energy, molybdenum ''softening'' is observed, H_#mu# curve within straggling zone is well described by alloyage calculated profile. #DELTA#a/a measurements within straggling zone are well described by damage profile. TEM-investigations have shown the developed defective structure even within molybdenum ''softening'' range.

206

Liquid zone system events at Wolsong Unit 2  

International Nuclear Information System (INIS)

On June 19, 1998, after the first annual outage, Wolsung Unit 2 was shutdown at a controlled rate due to the continuous instability of Liquid Zone Control level. Investigation revealed that the Liquid Zone Control level instability was caused by water condensed inside the helium lines, generated from the moistened helium flow, especially, inside the helium balance header feed and bleed valve lines. It was found that improper installation of the diaphragm type isolation valves and the drain valve tap could easily contain the water inside the lines and be destined to form water traps causing the balance header pressure oscillation. After the lines were dried, Liquid Zone Control level instability was almost vanished, and approached the allowable equilibrium state. As the reactor power was increased, however, the zone level instability increased again. In order to compensate for the excessive, the Bulk ...

1998-09-07

207

Determination of the emission zone in a single-layer polymer light-emitting diode through optical measurements  

Science.gov (United States)

We study the emission zone in a single-layer polymer light-emitting diode. The emission zone is found by studying the angular distribution of the electroluminescence. The emission is modeled by accounting for optical interference. We account for birefringence of the anode layer in our model. The active polymer was, however, found to be isotropic. The anode consists of a single-layer of the conducting polymer complex poly(3,4-ethylenedioxythiophene) and poly(styrene sulfonate) (PEDOT-PSS), with enhanced conductivity. As a cathode we use plain aluminum. By using only PEDOT-PSS we avoid having a thin metal layer or indium-tin-oxide as the anode in the path of the escaping light. The active material is a substituted polythiophene with excellent film forming properties. A comparison between the experimental and calculated angular distribution of light emission from a single-layered polymer light-emitting diode was shown to be in good agreement for ...

2001-06-01

208

Annual report on monitoring of the unsaturated zone and recharge areas at INEL to the state of Idaho INEL Oversight Committee  

Energy Technology Data Exchange (ETDEWEB)

During the early years of the INEL, the USGS conducted extensive studies (sitewide drilling program) of the geology and hydrology of the area collecting varied data over the years. The unsaturated zone has not received much attention until recently. The studies that have been done are a result of problems or concerns arising from liquid radioactive waste disposal. The TRA facility has the most information published about its waste disposal activities. The ICPP has less data about the unsaturated zone due to the fact that most waste water disposal has been to a well. Little is known about the effect of waste water disposal at the NRF on the unsaturated zone. Essentially no information was found about waste disposal activities at other facilities, primarily because there does not appear to be any reported problems associated with waste water disposal at these locations. The RWMC has received much attention in the last few ...

1992-01-01

209

Annual report on monitoring of the unsaturated zone and recharge areas at INEL to the state of Idaho INEL Oversight Committee  

Energy Technology Data Exchange (ETDEWEB)

During the early years of the INEL, the USGS conducted extensive studies (sitewide drilling program) of the geology and hydrology of the area collecting varied data over the years. The unsaturated zone has not received much attention until recently. The studies that have been done are a result of problems or concerns arising from liquid radioactive waste disposal. The TRA facility has the most information published about its waste disposal activities. The ICPP has less data about the unsaturated zone due to the fact that most waste water disposal has been to a well. Little is known about the effect of waste water disposal at the NRF on the unsaturated zone. Essentially no information was found about waste disposal activities at other facilities, primarily because there does not appear to be any reported problems associated with waste water disposal at these locations. The RWMC has received much attention in the last few ...

1992-12-31

210

The edge of neutral evolution in social dilemmas  

Energy Technology Data Exchange (ETDEWEB)

The functioning of animal as well as human societies fundamentally relies on cooperation. Yet, defection is often favorable for the selfish individual, and social dilemmas arise. Selection by individuals' fitness, usually the basic driving force of evolution, quickly eliminates cooperators. However, evolution is also governed by fluctuations that can be of greater importance than fitness differences, and can render evolution effectively neutral. Here, we investigate the effects of selection versus fluctuations in social dilemmas. By studying the mean extinction times of cooperators and defectors, a variable sensitive to fluctuations, we are able to identify and quantify an emerging 'edge of neutral evolution' that delineates regimes of neutral and Darwinian evolution. Our results reveal that cooperation is significantly maintained in the neutral regimes. ...

2009-09-15

211

Measurement of Turbulence Decorrelation during Transport Barrier Evolution in a High Temperature Fusion Plasma  

Energy Technology Data Exchange (ETDEWEB)

A low power polychromatic beam of microwaves is used to diagnose the behavior of turbulent fluctuations in the core of the JT-60U tokamak during the evolution of the internal transport barrier. A continuous reduction in the size of turbulent structures is observed concomitant with the reduction of the density scale length during the evolution of the internal transport barrier. The density correlation length decreases to the order of the ion gyroradius, in contrast to the much longer scale lengths observed earlier in the discharge, while the density fluctuation level remain similar to the level before transport barrier formation.

2005-03-29

212

Evolution of a vacuum shell in the Friedmann-Schwarzschild world  

International Nuclear Information System (INIS)

The method of an effective potential is used to investigate the possible types of evolution of vacuum shells in the Friedmann-Schwarzschild world. Such shells are assumed to emerge during phase transitions in the early Universe. The possible global geometries are constructed for the Friedmann-Schwarzschild worlds. Approximate solutions to the equation of motion of a vacuum shell have been found. The conditions under which the end result of the evolution of the vacuum shells under consideration is the formation of black holes and wormholes with baby universes inside have been found. The interior of this world can be a closed, flat, or open Friedmann universe.

2008-08-01

213

Viewing the Constellations with Binoculars  

CERN Document Server

A guide to practical astronomy. It introduces the reader to some basic (and some not-so-basic) astronomical concepts, and discusses the stars and their evolution, the planets, nebulae, and distant galaxies

2010-01-01

214

Towards a Synthetic Chloroplast  

UK PubMed Central (United Kingdom)

BackgroundThe evolution of eukaryotic cells is widely agreed to have proceeded through a series of endosymbiotic events between larger cells and proteobacteria or cyanobacteria,...Full Text Available

215

TEST PLANNING APPROACH AND LESSONS. - NASA Technical Report Server ...  

Science.gov (United States)

requirements) + f3(accuracy of analyses) + f4(accuracy of fabrication) + f5( design time) + .... Learning curves suggest an evolution in rocket engines& ...

216

TAIL FLIP AND ESCAPE RESPONSE OF TETHYSBAENA ARGENTARII (MALACOSTRACA: THERMOSBAENACEA)  

Science.gov (United States)

... A. Ferrero. 2000. Escape behaviour in the stomatopod crustacean Squilla mantis, and the evolution of the caridoid escape reaction. ... ...

217

Stars, their evolution and their stability  

Energy Technology Data Exchange (ETDEWEB)

The Nobel lecture of Chandrasekhar is printed in which he describes the basic processes that determine the life history of a star with particular emphasis on the roles of stellar mass and radiation pressure. (AIP)

1984-04-01

218

SIM: Stellar Astrophysics - SIM - NASA  

Science.gov (United States)

... and one near-main-sequence star, which will stringently constrain calculations of single-star evolution at high metallicity. Independent of SIM Lite observations ...

219

Reference List-W  

Science.gov (United States)

A SCENARIO FOR CARBON STAR EVOLUTION WILLEMS, F., DE JONG, T. 213> 821111 INFRARED OBSERVATIONS OF OH/IR STARS WILLIAMS, D. M., BOYLE, ...

220

RXTE GOF: News Archive 2004 - HEASARC - NASA  

Science.gov (United States)

May 18, 2007 ... This exciting new development in neutron star evolution was presented at the Winter 2004 AAS Meeting in Atlanta, Georgia. ...

221

ROSAT Status 130: Update on Wurzburg Conference - HEASARC - NASA  

Science.gov (United States)

Aug 21, 1995... F.D. Two Southern Supernova Remnants Shibazaki, N. Effect of a Superfluid- Crust Coupling on the Neutron Star Evolution Siddiqui, ...

222

Quantitative Spectroscopy of Photospheric-Phase Type II SN  

Science.gov (United States)

... and high-quality photospheric-phase Type II SN spectra to constrain core- collapse SN explosions, massive star evolution, and distances in the Universe ...

223

Pulsational instability in massive stars: implications for ...  

Science.gov (United States)

sive star evolution based on our new calculations of this pulsational instability, where the initial mass of SNe progenitors increases according to the ...

224

Protoplanetary Disks of Binary Systems in Orion  

CERN Document Server

Dusty primordial disks surrounding young low-mass stars are revealing tracers of stellar and planetary formation. The evolution and lifetime of these disks define the boundary conditions of the mechanisms of planet formation. Stellar companions, however, can significantly change this evolution through their tidal interactions. Stellar evolution and planet formation in binaries have to respond to an environment of truncated, quickly disappearing disks--very different compared to an isolated star environment. In order to investigate details of the influence of binarity on circumstellar disk evolution, we obtained adaptive optics supported near-infrared imaging and spectroscopy of the individual components of 22 low-mass binaries in the well-known Orion Nebula Cluster. Brackett gamma emission, which we detect in several systems, is used as a tracer for the presence of an active accretion disk around each ...

2010-01-01

225

Printed product downloads - NASA Space Place  

Science.gov (United States)

Aug 26, 2011 ... The main article on the back of the poster explains star evolution in very simple terms (including the fate of our own Sun), and how a planetary ...

226

Prestin and high frequency hearing in mammals  

UK PubMed Central (United Kingdom)

Recent evidence indicates that the evolution of ultrasonic hearing in echolocating bats and cetaceans has involved adaptive amino acid replacements in the cochlear gene prestin. A substantial...Full Text Available

2011-03-01

227

Planet Forming Protostellar Disks - NASA Technical Report Server ...  

Science.gov (United States)

terms of 11) numerical models, 2D SPH simulations, and analytic models. The 1D model was useful for determining the evolution over very long timescales. ...

228

Phylogenomic analyses of malaria parasites and evolution of their exported proteins  

UK PubMed Central (United Kingdom)

BackgroundPlasmodium falciparum is the most malignant agent of human malaria. It belongs to the taxon Laverania, which includes other ape-infecting Plasmodium...Full Text Available

229

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) ...

230

PPT - AstroGravS - NASA  

Science.gov (United States)

Form as the end result of massive star evolution; Type II supernova: collapse of iron core in highly evolved massive star; outer regions blasted away in ...

231

ON THE BINDING ENERGY PARAMETER #lambda# OF COMMON ENVELOPE EVOLUTION  

International Nuclear Information System (INIS)

The binding energy parameter #lambda# plays an important role in common envelope evolution. Previous works have already pointed out that #lambda# varies throughout the stellar evolution, though it has been adopted as a constant in most of the population synthesis calculations. We have systematically calculated the binding energy parameter #lambda# for both Population I and Population II stars of masses 1-20 M _s_u_n, taking into account the contribution from the internal energy of stellar matter. We present fitting formulae for #lambda# that can be incorporated into future population synthesis investigations. We also briefly discuss the possible applications of the results in binary evolutions.

2010-06-10

232

New Frontiers in Binary Stars: Science at High Angular ...  

Science.gov (United States)

... interacting systems in which common-envelope evolutionary effects make it hard to generalize the results to single-star evolution, although they ...

2011-05-15

233

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

234

NASA Direct! - Kennedy Space Center - Home - NASA  

Science.gov (United States)

Aug 21, 2003 ... Her research interests have included hot stars, colliding stellar winds, binary star evolution and evolved stellar companions. ...

235

Irregularities in Ionospheric Plasma Clouds: Their Evolution ...  

Science.gov (United States)

... follows draws on Wittwer (1980b & c), Zinn et al. (1966) and Hess (1968). ... for the Starfish event) and much larger distances along the geomagnetic ...

1980-09-01

236

Introduction & Overview to Symposium 240: Binary Stars as ...  

Science.gov (United States)

... CVn) consisting of a dM3 star and a cool white dwarf that must have evolved through the common-envelope stage of binary star evolution (Else van ...

2011-05-14

237

High Energy Astrophysics Picture Of the Week - HEASARC - NASA  

Science.gov (United States)

Jun 28, 2010 ... Ultracompact binaries represent the end product of a binary star evolution, and are important test cases of theories of extreme gravity. Perhaps ...

238

Grain mantles: The impact on grain evolution and selective extinction  

International Nuclear Information System (INIS)

Depletion studies are used to infer the presence of mantles and to constrain grain evolutionary models in the diffuse interstellar medium. The presence of these mantles appears to be important in the evolution of the grains inside diffuse as well as dense clouds. In dense clouds where the element-to-element abundances sometimes differ from those found in diffuse clouds, empirical relationships are starting to emerge between gas abundances and various types of peculiar selective extinction. These peculiar extinction curves may be the results of nonvolatile mantle formation on grain cores or may reflect chemical differences due to variations in the intrinsic metalicity from one cloud to another. A simple model of the time evolution of a parcel of gas and dust as observed by the depletion of two elements is presented. Different studies of grain evolution and selective extinction are discussed and compared.

1989-12-01

239

General Disclaimer One or more of the Following Statements may ...  

Science.gov (United States)

Hie synthesis of diverse biologically important compounds, under condi- tions which existed on the earth in the initial period of its evolution, ha; ...

240

GLYDER - Earth Science Technology Office (ESTO) - NASA  

Science.gov (United States)

goals for multisensor co-registration and fusion. 6 - 12.5 Km ..... Beta-Test toolkit for cyclogenesis and early evolution of cyclones ...

241

FIRST Workshop Presentation Abstract: Circumstellar Matter Around ...  

Science.gov (United States)

and the implications for massive star evolution. In recent years, the complex nature of the circumstellar regions of evolved massive stars has become apparent. ...

242

Experience of isolated sleep paralysis in clinical practice in Nigeria.  

UK PubMed Central (United Kingdom)

The supernatural fears associated with the experience of isolated sleep paralysis in the culture of developing countries is sometimes associated with the evolution of somatic symptoms of psychological...Full Text Available

1992-06-01

243

Evolution of plant senescence  

UK PubMed Central (United Kingdom)

BackgroundSenescence is integral to the flowering plant life-cycle. Senescence-like processes occur also in non-angiosperm land plants, algae and photosynthetic prokaryotes. Increasing...Full Text Available

244

Evolution of fruit and seed characters in the Diervilla and Lonicera clades (Caprifoliaceae, Dipsacales)  

UK PubMed Central (United Kingdom)

Background and AimsThe Diervilla and Lonicera clades are members of the family Caprifoliaceae (Dipsacales sensu Full Text Available

2009-08-01

245

Dimorphic Olfactory Lobes in the Arthropoda  

UK PubMed Central (United Kingdom)

Specialized olfactory lobe glomeruli relating to sexual or caste differences have been observed in at least five orders of insects, suggesting an early appearance of this trait in insect evolution....Full Text Available

2009-07-01

246

Content of hydrogen, helium, and heavy elements in Procyon  

Energy Technology Data Exchange (ETDEWEB)

The values of X = 0.77, Z = 0.035, and Y = 0.195 and the stage of evolution of Procyon are determined from the evolutionary tracks and the results of an analysis of the chemical composition of the atmosphere.

1985-05-01

247

Comparing Genomes within the Species Mycobacterium tuberculosis  

UK PubMed Central (United Kingdom)

The study of genetic variability within natural populations of pathogens may provide insight into their evolution and pathogenesis. We used a Mycobacterium tuberculosis high-density...Full Text Available

2001-04-01

248

Classification of the circumstellar disc evolution during the main accretion phase  

British Library Electronic Table of Contents (United Kingdom)

Abstract We performed hydrodynamical simulations to investigate the formation and evolution of protostars and circumstellar discs from the pre-stellar cloud. As the initial state, we adopted the molecular cloud core with two non-dimensional parameters representing the thermal and rotational energies. With these parameters, we derived 17 models and calculated the cloud evolution--104 yr-after the protostar formation. We found that early evolution of the star-disc system can be qualitatively classified into four modes: the massive-disc, early-fragmentation, late-fragmentation, and protostar-dominant modes. In the -massive-disc mode-, to which the majority of models belong, the disc mass is greater than the protostellar mass for over 104 yr and no fragmentation occurs in the circumstellar dis...

2011-01-01

249

Charting the Uncharted Waters - SIM - NASA  

Science.gov (United States)

gently constrain calculations of single-star evolution at high metallicity. Independent of SIM Lite observa- tions, we also propose to establish 4) how to ...

250

Calibrating Cosmological Chronometers: White Dwarf Masses ...  

Science.gov (United States)

... The second scenario is limited by the age of our Galaxy such that the lowest-mass WD that could be formed via single star evolution is ~0.47 M ...

2011-05-14

251

Binary stars - A look at some interesting ... - GISS Publications - NASA  

Science.gov (United States)

... each star goes. The results of (1) are compared with predictions based on (2) and on single star evolution theory to discover the various stages which occur. ...

252

Big bang nucleosynthesis  

Energy Technology Data Exchange (ETDEWEB)

A brief review of standard big bang nucleosynthesis theory and the related observations of the light element isotopes is presented. Implications of BBN on chemical evolution and constraints on particle properties will also be discussed.

2000-01-01

253

Astrobiology Research Priorities for Giant ... - Astrobiology - NASA  

Science.gov (United States)

Mar 6, 2009 ... remnants of massive star evolution) to worlds that are more reassuringly familiar. In the latter category, we now have excellent evidence ...

254

Ancestral Genomes, Sex, and the Population Structure of Trypanosoma cruzi  

UK PubMed Central (United Kingdom)

Acquisition of detailed knowledge of the structure and evolution of Trypanosoma cruzi populations is essential for control of Chagas disease....Full Text Available

2006-03-01

255

APOD: 2009 April 23 ... - Astronomy Picture of the Day - NASA  

Science.gov (United States)

Apr 23, 2009 ... Wolf-Rayet stars have over 20 times the mass of the Sun and are thought to be in a brief, pre-supernova phase of massive star evolution. ...

256

A Search for Core-Collapse Supernova Progenitors in Hubbk Space - NASA  

Science.gov (United States)

for massive star evolution, or they could all be very blue super- giant stars experiencing A , = 1-1.5 mag. The fact that the en- ...

257

A Nearby Old Halo White Dwarf Candidate from the Sloan ...  

Science.gov (United States)

... than the age of the universe unless it is an unresolved double degenerate or a product of common-envelope binary star evolution (Fontaine et al. ...

2008-07-01

258

+ HUBBLE CATCHES UP WITH A BLUE STRAGGLER STAR - NASA  

Science.gov (United States)

Our analysis confirms that, but without having to make any assumptions about the state of blue straggler star evolution," Saffer said. ...

259

Yttrium Y 90 Ibritumomab Tiuxetan, Fludarabine, Radiation Therapy, and Donor Stem Cell Transplant in Treating Patients With Relapsed or Refractory Non-Hodgkin's Lymphoma  

Science.gov (United States)

B-cell Chronic Lymphocytic Leukemia; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Splenic Marginal Zone Lymphoma; Waldenstrom Macroglobulinemia

2010-10-12

260

Redistribution of radionuclides between a microbial mat and a carbonate body at the Garga hot spring (Baikal Rift Zone)  

British Library Electronic Table of Contents (United Kingdom)

The features of present deposits that form in the vicinity of hot springs can provide clues to the parameters of paleowaters in places of past hydrothermal activity marked by remnant carbonate and/or siliceous sinter. We investigated a large carbonate body at the Garga hot spring developing in the Baikal zone of nitric hydrotherms in the Barguzin Rift Zone valley. The main focus was on the structure of the carbonate mound, as well as on the partitioning of radioactive elements between the cyanobacterial mat and the inorganic component of the body (the issue that has never been explored before). The cyanobacterial community of the Garga spring is an active biosorbent of 226Ra, 228Ra, 210Pb. The radionuclides accumulated by biosorption become preserved in minerals that form within the bacter...

2011-01-01

261

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 ...

1984-03-01

262

Influence of gully erosion control on amphibian and reptile communities within riparian zones of channelized streams  

British Library Electronic Table of Contents (United Kingdom)

Riparian zones of streams in northwestern Mississippi have been impacted by agriculture, channelization, channel incision, and gully erosion. Riparian gully formation has resulted in the fragmentation of remnant riparian zones within agricultural watersheds. One widely used conservation practice for controlling gully erosion is the installation of drop pipes. This practice involves placing earthen dams across eroding gullies and embedding a metal standpipe within the dam to convey water from the field to stream level. Installation of this structure halts gully erosion and incidentally replaces eroding gullies with riparian habitats. Previous research evaluating gully erosion control structures have not considered the ecological impacts of these conservation practices on amphibian and repti...

2009-01-01

263

Energy and reserve dispatch in a multi-zone electricity market  

Energy Technology Data Exchange (ETDEWEB)

Competitive bidding for ancillary services (A/S), in addition to bidding for energy, is increasingly recognized as an important part of electricity markets. In this paper, an LP-based approach is presented for solving the multi-product (i.e. energy and A/S products), multi-zone/area physical market dispatch problem. The approach can explicitly represent various constraints, such as reserve requirement constraints, network security limits, and sharing of constrained resource capacity (e.g. maximum unit generation) between energy and reserve. The joint dispatch method, which dispatches energy and reserve market concurrently, is extended to allow inter-zonal reserve trading in multi-zone competitive pool. Numerical examples are included to demonstrate the salient characteristics of the joint dispatch solution.

1999-08-01

264

Coastal Zone Management Act amendments of 1980. Hearing before the Committee on Commerce, Science, and Transportation, United States Senate, Ninety-Sixth Congress, Second Session on S. 2622, April 30, 1980  

Energy Technology Data Exchange (ETDEWEB)

Testimony at an April 30, 1980 hearing addressed whether to reauthorize or amend the Coastal Zone Management Act of 1978, specifically section 306, to further implement state programs and institutionalize state management of coastal zones. The text of the reauthorization bill (S. 2622) is followed by the statements of eleven witnesses and additional articles, letters, and statements submitted for the record. Witnesses are present for the fishing and oil industries, state and national governments, and public interest groups. Among the points brought out in testimony were that uniform standards are unwise - given the variety of coastal regions; and that there is a need to balance protection and development policies. (DCK)

1980-01-01

265

Chemical and sulphur isotope compositions of pyrite in the Jaduguda U (?Cu?Fe) deposit, Singhbhum shear zone, eastern India: Implications for sulphide mineralization  

British Library Electronic Table of Contents (United Kingdom)

The Jaduguda U (?Cu?Fe) deposit in the Singhbhum shear zone has been the most productive uranium deposit in India. Pyrite occurs as disseminated grains or in sulphide stringers and veins in the ore zone. Veins, both concordant and discordant to the pervasive foliation, are mineralogically either simple comprising pyrite ? chalcopyrite or complex comprising pyrite + chalcopyrite + pentlandite + millerite. Nickel-sulphide minerals, though fairly common in concordant veins, are very rare in the discordant veins. Pyrite in Ni-sulphide association is commonly replaced by pentlandite at the grain boundary or along micro-cracks. Based on concentrations of Co and Ni, pyrite is classified as: type-A ? high Co (up to 30800?ppm), no/low Ni; type-B ? moderate Co (up to 16500?ppm) and moderate to high ...

2011-01-01

266

Anti-Infection Dip Suggestions for the Coloplast Titan Inflatable Penile Prosthesis in the Era of the Infection Retardant Coated Implant  

British Library Electronic Table of Contents (United Kingdom)

Abstract Introduction.- Infection is the worst complication seen with inflatable penile prosthesis (IPP). Both the American Medical Systems (AMS) and Coloplast IPP have infection retardant coatings. AMS is coated at the factory with rifampicin and minocycline (InhibiZone). The Coloplast IPP has a hydrophilic coating covalently bonded to its components that will absorb any aqueous solution before implantation and provides increased surface lubricity to decrease bacterial adherence. Aim.- We tested several antibiotic dips comparing zones of inhibition (ZOI) against five commonly infecting bacteria with coated Coloplast implants. Results were compared with those ZOI created with strips of an AMS IPP precoated with InhibiZone. Methods.- Pieces of sterile Coloplast Titan IPP were dipped in (i) ...

2011-01-01

267

The evolution of x-ray binaries  

International Nuclear Information System (INIS)

These proceedings represent papers presented at the Astrophysics Conference in Maryland, USA. The topic of the Conference was the evolution of x-ray binaries and the papers encompass a wide range of subjects on x-ray astronomy. There were one hundred eighteen papers presented at the Conference and out of these three have been abstracted for the Energy Science and Technology database.

1993-10-11

268

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

269

THE EVOLUTION OF LYMAN LIMIT ABSORPTION SYSTEMS TO REDSHIFT SIX  

International Nuclear Information System (INIS)

We have measured the redshift evolution of the density of Lyman limit systems (LLSs) in the intergalactic medium over the redshift range 0 < z < 6. We have used two new quasar samples to (1) improve coverage at z #approx# 1, with GALEX grism spectrograph observations of 50 quasars with 0.8 < z_e_m < 1.3, and (2) extend coverage to z #approx# 6, with Keck ESI spectra of 25 quasars with 4.17 < z_e_m < 5.99. Using these samples together with published data, we find that the number density of LLS per unit redshift, n(z), can be well fit by a simple evolution of the form n(z) = n_3_._5[(1 + z)/4.5]"#gamma# with n_3_._5 = 2.80 #+-# 0.33 and #gamma# = 1.94"+"0"."3"6_-_0_._3_2 for the entire range 0 < z < 6. We have also reanalyzed the evolution of damped Ly#alpha# systems (DLAs) in the redshift range 4 < z < 5 using our high-redshift quasar sample. We find a total of 17 DLAs and sub-DLAs, which we ...

2010-10-01

270

Quantitative spectroscopy of close binary stars  

CERN Document Server

The method of spectral disentangling has now created the opportunity for studying the chemical composition in previously inaccessible components of binary and multiple stars. This in turn makes it possible to trace their chemical evolution, a vital aspect in understanding the evolution of stellar systems. We review different ways to reconstruct individual spectra from eclipsing and non-eclipsing systems, and then concentrate on some recent applications to detached binaries with high-mass and intermediate-mass stars, and Algol-type mass-transfer systems.

2011-01-01

271

Modelling the spatial and temporal evolution of winter glacier mass balance.  

Environmental Research Database

DescriptionChanges in glacier mass balance are critically influenced by the distribution of snow accumulation at the start of the melt season, but models of the winter season lag seriously behind those of the melt season. The overall aim is to test physically-based models of the spatial and temporal evolution of the winter snowpack at a temperate ice cap (Langjokull, Iceland), to assess how effectively and also how efficiently they capture variation in winter accumulation. A three-step modelling approach i [continued...

2004-01-31

272

Massive Stars in the Local Group: Star Formation and Stellar Evolution  

CERN Document Server

The galaxies of the Local Group that are currently forming stars can serve as our laboratories for understanding star formation and the evolution of massive stars. In this talk I will summarize what I think we've learned about these topics over the past few decades of research, and briefly mention what I think needs to happen next.

2003-01-01

273

Maintenance viewpoint of a successful reactor program  

International Nuclear Information System (INIS)

As the Operating and Support staffs of the FFTF organization have gained experience, the plant reliability and capacity factors have shown a steadily improving trend. The plant capacity factor for Cycle 4 was 99.5%. It is the purpose of this report to describe the evolution of the maintenance organization at the FFTF site from a general support organization to a technically proficient organization playing a major role in planning and performance of plant maintenance evolutions.

1984-06-03

274

Longitudinal and transverse mode evolution in free electron laser  

Energy Technology Data Exchange (ETDEWEB)

We use the method of Padg approximants and Fourier transform techniques to treat analytically the problem of transverse and longitudinal mode evolution in FELs. We obtain simple relations providing a transparent understanding of the dynamic of pulse propagation effects and of transverse mode guiding. We discuss the interplay with inhomogeneous broadening effects and derive gain formulae including longitudinal and transverse mode couplings.

1995-12-31

275

Hydrogen evolution on Ni-P alloys. The effect of deposition conditions  

Energy Technology Data Exchange (ETDEWEB)

The hydrogen evolution reaction (HER) was studied on Ni-P{sub x} electrodes containing 8 to 16 weight percent P prepared by potentiostatic deposition. The amount of P in the alloy varied with deposition potential. The activity of the electrodes was dependent on the P concentration, and the formation of a passive film. Cyclic voltametry was used to study the removal of this film. 3 refs.

1998-07-01

276

Hydrodynamic measurement of a single corrosion pit  

Energy Technology Data Exchange (ETDEWEB)

The hydrodynamics of gas evolution plays an important role in the pitting corrosion of metals. A new technique for the measurement of the local hydrodynamics caused by corrosion processes, using the atomic force microscope, has been presented in this work. The hydrodynamics of hydrogen evolution on Al surface due to pitting corrosion was studied. The characteristic features of the hydrodynamics are discussed. To the best of our knowledge this is the first local measurement of pitting corrosion hydrodynamics.

2004-11-01

277

Global effects of interactions on galaxy evolution  

International Nuclear Information System (INIS)

Recent observations of the evolutionary properties of paired and interacting galaxies are reviewed, with special emphasis on their global emission properties and star formation rates. Data at several wavelengths provide strong confirmation of the hypothesis, proposed originally by Larson and Tinsley, that interactions trigger global bursts of star formation in galaxies. The nature and properties of the starbursts, and their overall role in galactic evolution are also discussed.

1990-11-01

278

Gamma ray observations of the solar system  

Energy Technology Data Exchange (ETDEWEB)

Two general categories are discussed concerning the evolution of the solar system: the dualistic view, the planetesimal approach and the monistic view, the nebular hypothesis. The major points of each view are given and the models that are developed from these views are described. Possible applications of gamma ray astronomical observations to the question of the dynamic evolution of the solar system are discussed.

1981-01-01

279

Galactic deuterium abundance as a test of cosmological models  

Energy Technology Data Exchange (ETDEWEB)

The problem on change of deuterium abundance in the process of galactic evolution (star evolution, supernova explosions, nucleosynthesis in supermassive objects) is considered. It is shown that the observable deuterium quantity in the interstellar medium must correspond to its cosmological abundance. This conclusion is independent of the rate of accretion of intergalactic gas by Galaxy. The effect of hypothetical pregalactic active objects on cosmological deuterium is small. It is poind out that observations of interstellar deuterium in absorbtion at lambda=91.6 cm are significant.

1982-02-01

280

Experimental research of spontaneous evolution from ultracold rydberg atoms to plasma  

International Nuclear Information System (INIS)

The spontaneous evolution from ultracold Rydberg atoms to plasma is investigated in a caesium MOT by using the method of field ionization. The plasma transferred from atoms in different Rydberg states (n=22-32) are obtained experimentally. Dependence of the threshold time of evolving to plasma and the threshold number of initial Rydberg atoms on the principal quantum number of initial Rydberg states is studied. The experimental results are in agreement with hot-cold Rydberg-Rydberg atom collision ionization theory. (authors)

2008-04-01

281

Evolution of the luminosity function of quasar accretion disks  

International Nuclear Information System (INIS)

Using an accretion-disk model, accretion disk luminosities are calculated for a grid of black hole masses and accretion rates. It is shown that, as the black-hole mass increases with time, the monochromatic luminosity at a given frequency first increases and then decreases rapidly as this frequency is crossed by the Wien cutoff. The upper limit on the monochromatic luminosity, which is characteristic for a given epoch, constrains the evolution of quasar luminosities and determines the evolultion of the quasar luminosity function. 22 refs.

282

Evolution of a horizontal branch Population II star with total mass 0.63 Msub solar  

Science.gov (United States)

The theoretical evolution of a horizontal branch star of Population II is followed through the helium burning in the core phase and is compared with the results given by other investigators. The m- fluence of different physics and interpolation schemes in the opacity tables is discussed. Some thoughts are given on the explanation of the erratic period variations observed in some of the RR Lyrae variables in the globular clusters. (auth)

1973-01-01

283

Contribution of Gene Amplification to Evolution of Increased Antibiotic Resistance in Salmonella typhimurium  

UK PubMed Central (United Kingdom)

The use of β-lactam antibiotics has led to the evolution and global spread of a variety of resistance mechanisms, including β-lactamases, a group of enzymes that degrade the β-lactam...Full Text Available

2009-08-01

284

Studies on the Evolution of Silver Nanoparticles in Micelle by UV-Photoactivation  

Energy Technology Data Exchange (ETDEWEB)

Ultraviolet (UV) photoirradiation of Ag(I) compounds in the presence of an aqueous Triton X-100 solution has been exploited for the first time to prepare reproducible yellow silver hydrosol. The evolution of nanosized silver particles has been examined critically under the influence of different anions/ligands. Hence, time dependent evolution of silver hydrosol from different silver compounds in micelle via photochemical reduction is observed. Anions/ligands of precursor salts have been found to show profound influence (due to electron scavenging property, solubility, stability etc.) on the evolution route and efficiency of photochemical reduction of Ag(I) to Ag(O) in micelle and thereby classification of silver compounds becomes possible. Kinetic results reveal that the formation of silver particles proceeds via autocatalytic growth mechanism. The observed variation in rate constant values for the ...

2003-12-15

285

N-body Models of Extended Clusters  

CERN Document Server

We use direct N-body simulations to investigate the evolution of star clusters with large size-scales with the particular goal of understanding the so-called extended clusters observed in various Local Group galaxies, including M31 and NGC6822. The N-body models incorporate a stellar mass function, stellar evolution and the tidal field of a host galaxy. We find that extended clusters can arise naturally within a weak tidal field provided that the tidal radius is filled at the start of the evolution. Differences in the initial tidal filling-factor can produce marked differences in the subsequent evolution of clusters and the size-scales that would be observed. These differences are more marked than any produced by internal evolution processes linked to the properties of cluster binary stars or the action of an intermediate-mass black hole, based on models performed in this work and ...

2010-01-01

286

Formation and dynamical evolution of galaxies and of their components  

CERN Document Server

From this vast subject, I will pick out and review three specific topics, namely the formation and evolution of bars, the formation of bulges, and the evolution during multiple major mergers. Bars form naturally in galactic discs. Their evolution is driven by the exchange of angular momentum within the galaxy. This is emitted mainly by near-resonant material in the inner disc (bar), and is absorbed by near-resonant material in the outer disc and in the halo. As a result of this, the bar becomes stronger and rotates slower. Bulges are not a homogeneous class of objects. Based on their formation history, one can distinguish three types. Classical bulges are mainly formed before the actual disc component, from collapses or mergers and the corresponding dissipative processes. Boxy/peanut bulges are parts of bars seen edge-on. Finally, disc-like bulges are formed by the inflow of material to the center due to bar torques. Major ...

2005-01-01

287

Use of solid state nuclear track detectors for radon concentration measurements indoors  

International Nuclear Information System (INIS)

An indoor radioactive survey is being conducted in an Italian district. Preliminary results identified a zone with significant radioactive levels, in which a new specific survey has been planned. In this paper attention is dedicated mainly to radon measurement technique and results.

288

Upward migration of underground injected wastes through hydrologic conduits around the wellbore  

Energy Technology Data Exchange (ETDEWEB)

Underground injection, compared to other waste disposal methods, is considered to have the advantages of isolating wastes in a confined brine aquifer well below the horizon of human activity and underground sources of drinking water (USDWs). While most of injected wastes move laterally in the injection zone, posing a long-term concern to the human health and environment, a small amount can migrate upward to the upper aquifers, causing a greater threat to the quality of USDWs. Both the dual porosity and the single porosity models were used to investigate the migration of injected wastes through these hydrologic conduits. The results indicate that regional upward migration through an extensive confining formation is a slow process. Nevertheless, injected wastes can move upward rapidly through microannuli and channels in the cement sheath and spread over a distance in the upper aquifer. The wastes can also migrate fast through fractures in the disturbed ...

1988-01-01

289

There Goes the Neighborhood: Relational Algebra for Spatial Data Search  

CERN Document Server

We explored ways of doing spatial search within a relational database: (1) hierarchical triangular mesh (a tessellation of the sphere), (2) a zoned bucketing system, and (3) representing areas as disjunctive-normal form constraints. Each of these approaches has merits. They all allow efficient point-in-region queries. A relational representation for regions allows Boolean operations among them and allows quick tests for point-in-region, regions-containing-point, and region-overlap. The speed of these algorithms is much improved by a zone and multi-scale zone-pyramid scheme. The approach has the virtue that the zone mechanism works well on B-Trees native to all SQL systems and integrates naturally with current query optimizers - rather than requiring a new spatial access method and concomitant query optimizer extensions. Over the last 5 years, we have used these techniques extensively in our work on ...

2004-01-01

290

Theoretical electron-positron zone-reduced momentum density for YBa_2Cu_3O_7: Fermi surface and wave-function effects  

International Nuclear Information System (INIS)

Using the linearized augmented-plane-wave (LAPW) -calculated electron and positron charge densities for YBa_2Cu_3O_7, the Brillouin-zone-reduced electron-positron momentum density is computed and the zone-reduced two-dimensional angular correlation of annihilation radiation (2D ACAR) spectrum is produced. The calculations show that the relative weights of the Fermi-surface discontinuities are substantially altered due to the positron preferentially sampling the Cu-O chain region. In addition, the reduced 2D ACAR spectrum contains large k-dependent wave-function effects. The theoretical zone-reduced 2D ACAR spectrum is compared to the several existing experimental spectra. It is concluded that, at present, positron-annihilation experiments do not provide consistent and clear evidence for the existence and shapes of Fermi surfaces in YBa_2Cu_3O_7.

291

The high Andes, gene flow and a stable hybrid zone shape the genetic structure of a wide-ranging South American parrot  

UK PubMed Central (United Kingdom)

BackgroundWhile the gene flow in some organisms is strongly affected by physical barriers and geographical distance, other highly mobile species are able to overcome such constraints....Full Text Available

292

Receptive Field Remodeling Induced by Skin Stimulation in Cerebellar Neurons in vivo  

UK PubMed Central (United Kingdom)

The receptive field of a neuron reflects its function. For example, for parallel fiber (PF) inputs in C3 zone the cerebellar cortex, the excitatory and inhibitory receptive fields of a Purkinje cell...Full Text Available

293

Principles of room air flow; Grundlagen der Raumluftstroemung  

Energy Technology Data Exchange (ETDEWEB)

The following subjects are dealt with: physics of indoor air flow, flow in individual rooms, exchange of air and pollution between individual building zones and with the outside world, thermal coupling with the building shell, thermal comfort and air quality, evaluation of the ventilation. figs., tabs., refs.

1994-12-31

294

Pedicled Thoracoabdominal Flap Coverage About the Elbow in Traumatic War Injuries  

UK PubMed Central (United Kingdom)

Current military conflicts in Iraq and Afghanistan have produced a significant number of complex injury patterns. Multiple extremity trauma and wide zones of injury mandate a flexible approach to these...Full Text Available

2010-03-01

295

Paraquat-induced resinosis in Japanese pine. I. The effect of paraquat on Pinus densiflora and P. thunbergii  

Energy Technology Data Exchange (ETDEWEB)

Treatment of Japanese pines (P. densiflora and P. thunbergii) with paraquat induced a zone of lightwood. Determinations of turpentine and ether extractives contents in lightwoods showed high levels as compared with those in control woods. (Refs. 5).

1980-01-01

296

NAME=\\  

Wastenet

...this pathway study the following two focus modules (in addition to the six core modules) and carry out a research investigation within this theme: Agricultural Production Systems Considers the type of farming systems that have evolved globally in relation to the prevailing agro-climatic zones, the influences of economic factors ...

297

Microstructures for high-energy x-ray and particle-imaging applications  

Energy Technology Data Exchange (ETDEWEB)

Coded imaging techniques using thick, micro-Fresnel zone plates as coded apertures have been used to image x-ray emissions (2-20 keV) and 3.5 MeV Alpha particle emissions from laser driven micro-implosions. Image resolution in these experiments was 3-8 ..mu..m. Extension of this coded imaging capability to higher energy x-rays (approx. 100 keV) and more penetrating charged particles (e.g. approx. 15 MeV protons) requires the fabrication of very thick (50-200 ..mu..m), high aspect ratio (10:1), gold Fresnel zone plates with narrow linewidths (5-25 ..mu..m) for use as coded aperatures. A reactive ion etch technique in oxygen has been used to produce thick zone plate patterns in polymer films. The polymer patterns serve as electroplating molds for the subsequent fabrication of the free-standing gold zone plate structures.

1981-05-01

298

Microstructures for high-energy x-ray and particle imaging applications  

Energy Technology Data Exchange (ETDEWEB)

Coded imaging techniques using thick, micro-Fresnel zone plates as coded apertures have been used to image x-ray emission (2--20 keV) and 3.5 MeV Alpha particle emissions from laser driven micro-implosions. Image resolution in these experiments was 3--8 ..mu..m. Extension of this coded imaging capability to higher energy x rays (approx.100 KeV) and more penetrating charged particles (e.g., approx.15 MeV protons) requires the fabrication of very thick (50--200 ..mu..m), high aspect ratio (10:1), gold Fresnel zone plates with narrow linewidths (5--25 ..mu..m) for use as coded apertures. A reactive ion etch technique in oxygen has been used to produce thick zone plate patterns in polymer films. The polymer patterns serve as electroplating molds for the subsequent fabrication of the free-standing gold zone plate structures.

1981-11-01

299

Method of insulating bed water in an oil well  

Energy Technology Data Exchange (ETDEWEB)

A method is proposed for operating bed waters in an oil well by injecting silanes into the near-face zone. It is distinguished by the fact that in order to improve the effectiveness of insulation, the silanes used are silanes of general formula Si /SUB n/ H /SUB 2n-n/ .

1982-01-01

300

Identification of a Chemically Induced Point Mutation Mediating Herbicide Tolerance in Annual Medics (Medicago spp.)  

UK PubMed Central (United Kingdom)

Background and AimsSulfonylurea (SU) herbicides are used extensively in cereal–livestock farming zones as effective and cheap herbicides with useful levels of residual activity....Full Text Available

2008-05-01

301

Hydrogen behavior in the iron surface layer modified by plasma nitriding and ion boronising  

Energy Technology Data Exchange (ETDEWEB)

The effects of the plasma nitriding with the formation of compound nitride and diffusion zones and of the boronising with the different ion doses on hydrogen distribution and hydrogen induced deterioration of a surface layer were examined in the case of Armco iron. Electrochemical studies of hydrogen permeation rate, hydrogen vacuum extraction measurements, optical and scanning microscopy, X-ray diffraction and elastic recoil detection analysis (ERDA) were used. Accumulation of entering hydrogen within the various constituent zones of the modified layer inhibits the hydrogen transport into the metal and thus, decreases the mean hydrogen content in the deeper zones and in the core. Hydrogen accumulation within the compact nitride zone causes the expansion of the nitride lattice, nitride phase transformation and deterioration. The ion boronising enhances the hydrogen effects in the plasma nitrided layers. ...

2000-12-01

302

Human choice and climate change. Volume 2: Resources and technology  

Energy Technology Data Exchange (ETDEWEB)

Foreward: Preface; Introduction; The natural science of global climate change; Land and water use; Coastal zones and oceans; Energy and industry; Energy and social systems; Technological change; and Sponsoring organizations, International Advisory Board, and project participants.

1997-12-31

303

Field Investigations in the Tow Study Programme for Coastal Sediment Transport in the Netherlands.  

Science.gov (United States)

Field campaigns were conducted in 1981 and 1982/83 on the Dutch coast near Egmond. Measurements were made of surface elevations, water velocities and sediment concentrations in 3 to 8 surf zone locations and 2 to 5 offshore locations simultaneously. A des...

1985-01-01

304

Ecological aspects of air pollution emissions from an iron ore sintering plant in Ontario  

Science.gov (United States)

Sulfur dioxide emissions from an iron ore sintering plant have severely damaged vegetation up to 16 km northeast of the source. Concentric zones of increasing vegetation loss have formed around the point of maximum ground level concentration of the gas. Species diversity, sulfur and heavy metal concentrations in vegetation and soil amount to SO/sub 2/ injury were measured along a transect through the injury zones. Surrounding a central denuded area were zones dominated respectively by tussock-forming hair grass (Deschampsia flexuosa); low-growing shrubs and trailers (Sambucus pubens, Polygonum cilinode); higher-growing shrubs and suckering Populus tremuloides and Betula papyrifera) stunted forest tree species (Populus, Betula, Picea glauca, Abies Balsamea), and finally, normal boreal forest flora. Although SO/sub 2/ injury is continuing in this area, these zones now appear to be maintained primarily by ...

1975-01-01

305

ESTROGEN AND ADULT NEUROGENESIS IN THE AMYGDALA AND HYPOTHALAMUS  

UK PubMed Central (United Kingdom)

In mammals, adult neurogenesis has been extensively studied in the dentate gyrus of the hippocampus and subventricular zone. However, newly proliferated neurons have also been documented in...Full Text Available

2008-03-01

306

Compact Image Slicing Spectrometer (ISS) for hyperspectral fluorescence microscopy  

UK PubMed Central (United Kingdom)

An image slicing spectrometer (ISS) for microscopy applications is presented. Its principle is based on the redirecting of image zones by specially organized thin mirrors within a custom fabricated...Full Text Available

2009-07-20

307

Baccharis Salicifolia development in the presence of high concentrations of uranium in the arid environment of San Marcos, Chihuahua  

International Nuclear Information System (INIS)

In humid zones and marine environments the bio indicator contaminants by trace elements are well established. However, in arid zones it is more difficult to find these tools because there is less biodiversity. The objective of this paper was to analyze the behavior of the Baccharis salicifolia plant in areas with high uranium concentration in arid zones, to determine the characteristics of tolerance and possible use as a bio monitor for the presence of such contaminants. For this project a uraniferous zone was selected in San Marcos, located northwest of the City of Chihuahua. A total of 8 sampling points of the plant and soil were located here. Each sample was divided into the root and the stem and leaves to determine the specific activity of the uranium in both parts of the plant and its sediments. The determination of the specific activities of the total uranium in the samples was obtained by liquid ...

2011-02-01

308

Assessment of forest fuel loadings in Puerto Rico and the US ...  

Science.gov (United States)

Jun 16, 2011 ... Results indicated that fuel loadings averaged 24.05 Mg ha 1 in 2004–2006. Forest litter decreased from wetter to drier forest life zones. ...

309

Amygdala projections to central amygdaloid nucleus subdivisions and transition zones in the primate  

UK PubMed Central (United Kingdom)

In rats and primates, the central nucleus of the amygdala (CeN) is most known for its role in responses to fear stimuli. Recent evidence also shows that the CeN is required for directing attention...Full Text Available

2009-03-17

310

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

UK PubMed Central (United Kingdom)

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

2007-03-13

311

The growth factor from plerocercoids of Spirometra mansonoides is both a growth hormone agonist and a cysteine proteinase.  

Science.gov (United States)

Plerocercoids of the tapeworm Spirometra mansonoides produce a substance that stimulates growth of experimental hosts. We report purification of plerocercoid growth factor (PGF) to homogeneity by a process involving isolation and solubilization of plerocercoid membranes, isoelectric point selection by chromatofocusing chromatography or preparative isoelectric focusing, and anion-exchange chromatography. A radioreceptor assay (RRA) for human growth hormone (hGH) was used to detect PGF and purity of the 27.5-kDa protein was judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Proteolytic activity was detected in the 27.5-kDa protein by gelatin substrate PAGE. Characterization of PGF as a neutral cysteine proteinase was based on substrate and inhibitor specificities and dependence on pH and thiol-containing reagents. The association of hGH agonist and proteinase activities was shown by comparing RRA and hydrolytic activities in the presence ...

1996-04-01

312

Suppressive effects of cadmium on neurons and affected proteins in cultured developing cortical cells  

International Nuclear Information System (INIS)

The purpose of the present study was to examine the in vitro effects of low-dose cadmium (Cd) on developing cortical cells. The cortical cells removed from fetuses (embryonic day 15) were treated with 10 nM of Cd for 24 h. The effects of Cd on dendritic and synaptic development were immunocytochemically observed with anti-microtubule associated protein-2 (MAP2) and anti-synapsin I antibodies, respectively. Administration of Cd suppressed dendritic as well as synaptic development at 10 nM. By two-dimensional gel electrophoresis and liquid chromatography-tandem mass spectrometric (LC/MS/MS) analysis, we identified three proteins with different expression after Cd-treatment; dihydropyrimidinase-related protein 2 (DRP-2/CRMP-2), 14-3-3-epsillon and calmodulin (CaM). Though the number of identified proteins was small, these proteins are known to be involved in neuronal development. The present study demonstrated the morphological effects as well as affected proteins in ...

2008-11-20

313

Recent advances in analytical determination of cisplatin and its hydrolysis products  

International Nuclear Information System (INIS)

Cisplatin (cis-diaminedichloroplatinum [II] is a coordination compound, used in the treatment of several solid tumors. Cisplatin and its hydrolysis products exhibit a great pharmacological effect but are very toxic and probably carcinogenic. The present review summarizes the most important advances in the last years in the techniques employed for the detection and quantification of cisplatin and its hydrolysis products and in the different matrixes studied. The new emerging techniques and their modifications recently developed, fundamentally the combined use of detection and separation techniques for the analysis of platinum species and their impact on the speed, sensitivity and specificity of the analytical determination, with regard to the techniques used in the last century are discussed. High-Performance Liquid Chromatography and Capillary Electrophoresis, coupled with detection methods such as Mass Spectrometry, Inductively Coupled Plasma-Mass Spectrometry, ...

2009-01-01

314

Radioactive-electrophoretic assay of adenosine 5'-triphosphate sulfurylase activity in crude extracts with sulfate or selenate as a substrate  

Energy Technology Data Exchange (ETDEWEB)

An assay method for ATP sulfurylase is presented which employs Na/sub 2/(35)SO/sub 4/ as a substrate and measures the production of labeled adenosine 5'-phosphosulfate and 3'-phosphoadenosine 5'-phosphosulfate by low-voltage, hanging paper strip electrophoresis. The method is applicable to crude bacterial or mammalian extracts and accurately measures picomole amounts of product(s). Na/sub 2/(/sup 75/)SeO/sub 4/ can also be employed as a substrate, if the unstable radioactive product, adenosine 5'-phosphoselenate, is converted to elemental /sup 75/Se degrees by inclusion of reduced glutathione in the reaction mixture. The same paper strip electrophoretic technique can then be used to separate /sup 75/Se degrees from the radiolabeled substrate. The method also has utility for measuring any direct reduction by crude microbial extracts of radioactive selenate to selenite, independent of ATP sulfurylase.

1989-02-01

315

Purification and partial characterization of glycosaminoglycans and proteoglycans from cultured rabbit smooth muscle cells  

Energy Technology Data Exchange (ETDEWEB)

Glycosaminoglycans synthesized by cultured rabbit smooth muscle cells were isolated after incorporation of (/sup 3/H)-glucosamine into glycosaminoglycans in the presence or absence of 10% fetal bovine serum. Glycosaminoglycans were quantitated by two-dimensional electrophoresis after proteolytic digestion of the cell layers and media. The results show that the presence of serum has no effect on the chondroitin sulfate, heparan sulfate and dermatan sulfate content of the cell layers. The incorporation of (/sup 3/H)-glucosamine into hyaluronic acid of the cell layers was three times higher in the presence of serum. In the medium , the quantity of hyaluronic was two times higher in the presence of serum while the other glycosaminoglycans remained unchanged. The incorporation of (/sup 3/H)-glucosamine into hyaluronic acid was unaffected by the presence of serum. Specific proteoglycans were isolated from medium after with (/sup 35/S)-sulfate and (/sup 3/H)-serine by ...

1985-01-01

316

Proteomic Analysis of Proteins Secreted by HepG2 Cells Treated with Butyl Benzyl Phthalate  

British Library Electronic Table of Contents (United Kingdom)

Proteomic changes in proteins secreted by human hepatocellular carcinomas (HepG2) cells exposed to butyl benzyl phthalate (BBP) were evaluated. HepG2 cells were treated with three different concentrations of BBP (0, 10, or 25 ?M) for 24 or 48 h. Following incubation, the cells were subjected to proteomic analysis using two different pI ranges (4-7 and 6-9) and large-size two-dimensional gel electrophoresis. Results showed resolution of a total of 2776 protein spots. Of these, 29, including 19 upregulated and 10 downregulated proteins, were identified by electrospray ionization-mass spectrometry-mass spectrometry (ESI-MS/MS). Among these, the identities of cystatin C, Rho guanine nucleotide dissociation inhibitor, gelsolin, DEK protein, Raf kinase inhibitory protein, triose phosphate ...

2010-01-01

317

Proteins of the kidney microvillar membrane  

International Nuclear Information System (INIS)

Two methods were used to label pig kidney microvillar membrane proteins from the luminal and cytoplasmic surfaces of closed membrane vesicles. The first method was lactoperoxidase-catalysed radioiodination. Lactoperoxidase and glucose oxidase were positioned inside or outside the vesicles, iodination being initiated by adding glucose and "1"2"5I. After electrophoresis of the proteins, asymmetric labelling patterns on radioautographs were observed. However the major disadvantage of this method was the high degree of intramembrane labelling of the fatty acid chains of membrane lipids. The second method overcame this disadvantage. A new hydophilic photoreagent, 3,5-di("1"2"5I)iodo-4-azidobenzenesulphonate, was transported by a Na"+-dependent system into microvillar vesicles, thus permitting labelling from either side of the membrane when the vesicles were photolysed. The activity of several microvillar peptidases survived the labelling reaction and they could be ...

318

Labelling of bleomycin with cobalt-57, indium-111, technetium-99m, mercury-197, lead-203, and copper-67  

International Nuclear Information System (INIS)

The radiochemical purity of the cobalt-57 complex of bleomycin could be enhanced by adjusting the pH of the final product to a value between 5 and 6. This radiopharmaceutical appeared to have better tumor visualizing properties compared to the not neutralized preparation. The clinical use of the cobalt-57 bleomycin complex is however limited by the long physical half-life of the label, causing a risk of radioactive contamination. It appeared to be possible to label bleomycin with radioactive cations ("1"1"1In"3"+, sup(99m)Tc"4"+, "1"9"7Hg"2"+ and "6"7Cu"2"+) having suitable gamma ray energies and short half-lifes. These bleomycin complexes showed a high radiochemical purity judged by their behaviour on thin layer chromatography, paper chromatography, and electrophoresis, but their application as tumor visualizing radiopharmaceutical turned out to be disappointing compared with cobalt-57 bleomycin. (orig.).

319

Insulin-induced decrease in protein phosphorylation in rat adipocytes not explained by decreased A-kinase activity  

Energy Technology Data Exchange (ETDEWEB)

In isolated rat adipocytes, insulin inhibits lipolysis to a greater extent than would be predicted by the decrease in (-/+)cAMP activity ratio of cAMP-dependent protein kinase (A-kinase), from which it was speculated that insulin promotes the dephosphorylation of hormone-sensitive lipase. They have examined the phosphorylation state of cellular proteins under conditions of varying A-kinase activities in the presence and absence of insulin. Protein phosphorylation was determined by SDS-PAGE electrophoresis of extracts from /sup 32/P-loaded cells; glycerol and A-kinase activity ratios were measured in the cytosolic extracts from control, non-radioactive cells. Increased protein phosphorylation in general occurred over the same range of A-kinase activity ratios, 0.1-0.3, associated with increased glycerol release. The insulin-induced decrease in lipolysis was associated with a decrease in the /sup 32/P content of several proteins, an effect not explained by the modest ...

1987-05-01

320

Fiscal 1998 industrial science and technology R and D project. Research report on R and D of genome informatics technology (Development of stable oil supply measures using complex biosystem); 1998 nendo genome informatics gijutsu kenkyu kaihtsu seika hokokusho. Fukugo seibutsukei riyo sekiyu antei kyokyu taisaku kaihatsu  

Energy Technology Data Exchange (ETDEWEB)

This report describes the fiscal 1998 result on development of genome informatics technology. As comparative analysis technique of genes, the combination of electrophoresis and PCR was used. For improvement of the throughput and reproducibility of the technique, module- shuffling primers were used, and the multi(96)-arrayed capillary fragment analyzer was devised. The system detecting SNPs rapidly was also developed successfully. As analysis technology of DNA sequence by use of triple- stranded DNA formation, study was made on construction of long cDNA libraries, selective subtraction of specific sequences from libraries, and the basic technology of homologous cloning. Study was also made on each reaction step of IGCR technique for fast analysis, and specifications of a fluorescence transfer monitor. As modeling technique of genetic sequence information, the simulation model was developed for gene expression regulatory networks during muscle differentiation, and ...

1999-03-01

321

Expression of ribosomal genes in pea cotyledons at the initial stages of germination  

Energy Technology Data Exchange (ETDEWEB)

The time of appearance of newly synthesized rRNAs and ribosomal proteins (r-proteins) in the ribosomes of pea cotyledons (Pisum sativum L.) during germination was investigated. The ribosomal fraction was isolated and analyzed according to the method of germination of the embryo in the presence of labeled precursors or after pulse labeling of the embryos at different stages of germination. For the identification of newly synthesized rRNAs in the ribosomes we estimated the relative stability of labeled RNAs to the action of RNase, the sedimentation rate, the ability to be methylated in vivo in the presence of (/sup 14/C)CH/sub 3/-methionine, and the localization in the subunits of dissociated ribosomes. The presence of newly synthesized r-proteins in the ribosomes was judged on the basis of the electrophoretic similarity in SDS-disc electrophoresis of labeled polypeptides of purified ribosome preparations and of genuine r-proteins, as well as according to the ...

1986-01-20

322

Evaluation of heavy-metal ion toxicity in fish cells using a combined stress protein and cytotoxicity assay  

Energy Technology Data Exchange (ETDEWEB)

All organisms, from bacteria and yeast to humans, respond to physical and chemical stressors by increasing the synthesis of a small group of cellular stress proteins.'' The authors have developed a simple in vitro system for quickly screening environmentally relevant stressors to detect stress-induced proteins that are good candidates for biomarkers. Polyacrylamide gel electrophoresis was used to detect stressor-induced, concentration-dependent changes in cellular stress protein levels in two fish cell culture systems, whereas simultaneous in vitro neutral red uptake cytotoxicity assays measured the stressors effect on cellular physiology. There was a direct concentration-dependent relationship between sublethal cytotoxic effects and the increases in stress protein levels. Increases of 50 to 200% were detected in stress proteins from desert topminnow, Poeciliopsis lucida, hepatoma-derived cell cultures exposed to cadmium or copper. Three proteins ...

1994-08-01

323

Differentiation to adipocytes in accompanied by an increase in the amounts of Gi- and Go-proteins in 3T3-L1 cells  

International Nuclear Information System (INIS)

Treatment of cultures of 3T3-L1 cells with methylisobutyl-xanthine and dexamethasone has been shown to result in accumulation of lipid and conversion to the morphology of adipocytes in more than 90% of the cells. The status of the stimulatory (Gs), inhibitory (Gi) and Go-proteins during the course of 3T3-L1 differentiation was examined. The amount of alpha subunit of Gs (#alpha#Gs), assayed by radiolabeling in the presence of cholera toxin and ["3"2P]NAD"+, increased upon differentiation as previously described by others. The amounts of #alpha#Gi and #alpha#Go assayed by radiolabeling in the presence of pertussis toxin and ["3"2P]NAD"+ increased 3-fold upon differentiation. Immunoblots of cell membranes subjected to gel electrophoresis in sodium dodecyl sulfate were probed with two rabbit antisera raised against bovine brain #alpha#Go and with one raised against the#beta#-subunit of the bovine rod-outer-segment G-protein, referred to as transducin. The ...

1986-06-08

324

DNA alterations photosensitized by tetracycline and some of its derivatives  

Energy Technology Data Exchange (ETDEWEB)

Bacteriophage M13 mp10 DNA were irradiated with near-UV light in the presence of tetracycline derivatives and primed with synthetic oligonucleotide to be used for DNA synthesis using Escherichia coli DNA polymerase. Chain terminations were observed by denaturing polyacrylamide gel electrophoresis and mapped precisely. All the synthesis stops occurred before or at the level of guanine residues, showing that the photoreaction mediated by tetracycline derivatives led to a preferential alteration of guanine residues. These lesions were demonstrated to be induced in DNA through a pathway involving singlet oxygen. Tetracycline derivatives also photoinduced the breakage of the DNA sugar-phosphate backbone monitored by the conversion of supercoiled phi X174 DNA to a relaxed form. This lesion was shown to be initiated by hydroxyl radicals. The production of this free radical has been confirmed by electron paramagnetic resonance (EPR) spin trapping experiments using ...

1986-06-01

325

Construction of a human MluI YAC library  

Energy Technology Data Exchange (ETDEWEB)

The authors describe a cloning strategy for the construction of a human genomic library in yeast artificial chromosomes (YACs) based on complete digestion of high-molecular-weight DNA with the infrequently cutting restriction enzyme MluI. Cloning of MluI fragments in the vector pYAC-RC and one subsequent size fractionation by preparative pulsed-field gel electrophoresis yielded a library with average insert sizes of 600 kb. Ninety-seven percent of the colonies were recombinant. An additional size fractionation of MluI fragments prior to ligation had no significant influence on the size of the YACs. The library currently consists of 5000 clones, which is the equivalent of one human genome. Nineteen percent of the YACs were larger than 1.2 Mb. Since smaller MluI fragments are lost during sizing, they also performed cloning without size fractionation. Only 20% of the colonies were recombinant, probably due to unligated vector fragments that were present during the ...

1994-05-01

326

Cloning and linkage mapping of three polymorphic tetranucleotide (TAAA)[sub n] repeats on human chromosome 21  

Energy Technology Data Exchange (ETDEWEB)

The authors report the cloning, sequencing, and mapping of three short sequence repeat polymorphisms due to tetranucleotide (TAAA) repeats from human chromosome 21. These DNA markers (D21S221, D21S225, D21S226) have been cloned from the chromosome 21-specific plasmid library of J. C. Fuscoe, C. C. Collins, D. Pinkel, and J. W. Gray and were shown to be polymorphic by polymerase chain reaction amplification and polyacrylamide gel electrophoresis. Genotypes were determined in informative CEPH pedigrees and used in linkage analysis relative to other mapped markers on human chromosome 21. One of these markers, D21S221, is closely linked to the amyloid precursor protein gene (APP), which has been implicated in the etiology of familial Alzheimer disease in some families. 18 refs., 3 figs., 2 tabs.

1992-12-01

327

Characterization of mal recombination plasmids cloned in Streptococcus pneumoniae  

Energy Technology Data Exchange (ETDEWEB)

The malM locus of Streptococcus pneumoniae was cloned into one of the two PstI sites of the multicopy S. pneumoniae plasmid pMV158. To eliminate chromosomal transformants in the simultaneous selection for tetracycline resistance (coded by pMV158) and maltose utilization, the host cells contained a chromosomal deletion of the mal gene cluster. Two clones were isolated; one with a 3.3 kb insert (pLS70) which behaved like wild type with respect to maltose utilization, and another with a 2.9 kb insert (pLS69) which behaved as though it contained a down promoter mutation. Preliminary mapping of these clones by restriction analysis placed the 0.4kb deletion on a HindIII fragment in the interior of the chromosomal insert. The recombinant plasmids were able to transform over 50% of a recipient population to Mal/sup +/. Enzyme measurements of the clones indicated an overproduction of amylomaltase, constituting up to 10% of the total cellular protein, and supported the theory that the deletion ...

1981-01-01

328

Advanced organic analysis and analytical methods development: FY 1995 progress report. Waste Tank Organic Safety Program  

Energy Technology Data Exchange (ETDEWEB)

This report describes the work performed during FY 1995 by Pacific Northwest Laboratory in developing and optimizing analysis techniques for identifying organics present in Hanford waste tanks. The main focus was to provide a means for rapidly obtaining the most useful information concerning the organics present in tank waste, with minimal sample handling and with minimal waste generation. One major focus has been to optimize analytical methods for organic speciation. Select methods, such as atmospheric pressure chemical ionization mass spectrometry and matrix-assisted laser desorption/ionization mass spectrometry, were developed to increase the speciation capabilities, while minimizing sample handling. A capillary electrophoresis method was developed to improve separation capabilities while minimizing additional waste generation. In addition, considerable emphasis has been placed on developing a rapid screening tool, based on Raman and infrared spectroscopy, for ...

1995-09-01

329

"2"1"1At-Rh(16-S4-diol) - initial complex of radiopharmaceuticals labelled with astatine  

International Nuclear Information System (INIS)

Paper describes a new procedure to synthesize a pharmaceutical containing "2"1"1At. "2"1"1At"- anion was found to bind strongly with Rh"3"+ cation complexing with a thio-ether ligand - 1,5,9,13-tetratiacyclohexadecane-3,11-diol (16-S4-diol). One made use of "1"3"1I isotope to seek for the optimal conditions of the reaction. The derived complexes were studied by means of the paper electrophoresis, the ion exchange, the surface chromatography. One studied the kinetics of "1"3"1I"- anion binding with Rh(16-S4-diol), the dependence of the yield of "1"3"1I-Rh(16-S4-diol) forming complex on the temperature. the acidity of the reaction mixture and the concentration of the reagents. On the basis of the determined conditions of the synthesis one prepared "2"1"1At-Rh(16-S4-diol) complex by more astatide ("2"1"1At"-) to the equivalent amounts of RhCl_3 and tetra-thio-ether (16-S4-diol). One studied its behaviour

330

Zonal, provincial, lithological, and geomorphic features of soil salinization in the Southern federal okrug of Russia  

British Library Electronic Table of Contents (United Kingdom)

The relationships between soil salinization and the zonal and provincial bioclimatic conditions, the lithological composition of the sediments, and the geomorphic features of the territory have been analyzed for the Southern federal okrug of Russia. It is shown that the lithological and geomorphic conditions (relief, salinity of parent materials, degree of drainage, and the depth of saline groundwater) play an important role in the distribution of salt-affected soils against the background of the more general regularities specified by the climate. The participation of salt-affected soils in the soil cover of the Southern federal okrug increases in the eastward direction from the forest-steppe zone to the semidesert zone in agreement with an increase in the aridity and continentality of the...

2011-01-01

331

Uranium in the Gunnison county, Colorado  

Science.gov (United States)

Approximately 1.2 million kg of uranium oxide (yellow cake) has been produced from the area surrounding Gunnison, Colorado. Over 99 percent of this has come form the Cochetopa and Marshall Pass districts. Uranium in both districts and many of the other occurrences is associated closely with fault and shear zones which cut brittle host formations (sandstones and dolomites) of Paleozonic and Mesozoic age. Minor uranium occurrences are in pegmatites and shear zones in Precambrian rocks, Cambrian vein material, and sandstones of Tertiary age. In the paper presented, the uranium occurences are described by districts. In addition, possibilities for additional discoveries are discussed. (JMT)

1981-01-01

332

Red mud as a first stage catalyst in a two-stage close-coupled thermal catalytic hydroconversion process  

Energy Technology Data Exchange (ETDEWEB)

A process for the production of transportation fuels from heavy hydrocarbonaceous feedstock is provided comprising a two-stage, close-coupled process, wherein the first stage comprises a hydrothermal zone into which is introduced a mixture comprising a feedstock and red mud having coke-suppressing and demetalizing activity, and hydrogen; and the second, close-coupled stage comprises a hydrocatalytic zone into which substantially all the effluent from the first stage is directly passed and processed under hydrocracking conditions.

1985-12-17

333

Prediction of motions and tension in mooring lines on slack-moored floating oceanic architectural building in coastal zones  

Energy Technology Data Exchange (ETDEWEB)

The present paper is concerned with the prediction method for the motions and tensions of mooring lines on slack-moored floating oceanic architectural building in coastal zone. The motions and the tensions of mooring lines were estimated by the time domain numerical simulation in the present method. The present method includes the nonlinearity of mooring system, slow varying wave drift force. The authors performed a time domain numerical simulation for motions and the tensions of mooring lines on floating barge in two component waves. Also, the results obtained by numerical simulation were compared with the experimental results. The validity of the present method was confirmed.

1995-12-31

334

Migration of the long-lived radionuclides in soil-plant system under conditions of 30-km zone  

International Nuclear Information System (INIS)

Field experiments were conducted in the 30-km zone of Gomel's region of the Byelorussia to study factors aecting a biological radionuclide accessibility. A contamination density by radiocesium equaled 2,7-9,9 MBk/m"2, strontium 90 - 0,3-0,5 MBk/m"2 in 1991. A sowing of oats barley, lupin was carried out. It was shown that radionuclide accumulation by agricultural plants was determined basically by biological peculiarities of plants in greater degree than by the contamination density. It was shown that strontium 90 migration from the soil was more intensive than that of radiocesium. 8 tabs.

1992-05-15

335

Metals-impreganted red mud as a first-stage catalyst in a two-stage, close-coupled thermal catalytic hydroconversion process  

Energy Technology Data Exchange (ETDEWEB)

A process for the production of transportation fuels from heavy hydrocarbonaceous feedstock is provided comprising a two-stage, close-coupled process, wherein the first stage comprises a hydrothermal zone into which is introduced a mixture comprising a feedstock and metals-impregnated red mud having coke-suppressing and demetalizing activity, and hydrogen; and the second, close-coupled stage comprises a hydrocatalytic zone into which substantially all the effluent from the first stage is directly passed and processed under hydrocatalytic conditions. The preferred metals for impregnation include transition metals, in particular, nickel and molybdenum.

1985-12-17

336

Friction stir welding of dissimilar formed Mg alloys (AZ31/AZ91)  

Energy Technology Data Exchange (ETDEWEB)

Friction stir welding of dissimilar formed Mg alloys(AZ31/AZ91) was successfully carried out at the limited welding conditions. In a sound joint, SZ was mainly consisted of AZ31 Mg alloy which was located the retreating side. Dynamic recrystallization and grain growth occurred and {beta} intermetallic compounds of AZ 91 Mg alloy was not observed in SZ. BM had a higher hardness than that of the weld zone. The fracture location was not weld zone but BM of the AZ91 Mg alloy in tensile test. (orig.)

2005-07-01

337

Determination of the Venezuelan coastal-zone wind atlas by using numerical methods  

Energy Technology Data Exchange (ETDEWEB)

This work deals with the development of wind maps in the Venezuelan coastal zones (South America). The Navier-Stokes equations for real viscous incompressible flow are discretized via the finite element method and they are applied to a full 3D numerical model. Two regions were analyzed: the Margarita island and the Paraguana peninsula, both of them located in the Caribbean Sea at the North of Venezuela. These regions were modeled by using a three dimensional control volume, discretized through hexaedric eight-noded finite elements. Some wind maps obtained in this research are presented and discussed. (author)

1995-12-31

338

Accommodating tensions in the coastal zone: an introduction and overview  

Energy Technology Data Exchange (ETDEWEB)

This is the introductory paper for eight papers that follow in this issue of Natural Resources Journal that were presented at a symposium on the titled subject. The editor notes that two movements in recent decades have been identified with coastal regions - efforts to conserve natural resources and energy source development - and that profound social, economic, and political ramifications have attended these movements. He further notes that the tensions and demands created by the above two developments proved too much for state and local mechanisms, eventually culminating in the Coastal Zone Management Act of 1972. He then briefly evaluates the focus and success of CZMA and reviews the other papers. 58 references.

1985-01-01

339

Monitoring of DNA and cytogenetic damage in lymphocytes from persons with skin cancer diseases  

International Nuclear Information System (INIS)

There is a lot of interest in the studies that would help to understand whether there is a casual association between cancer and various types of molecular or cytogenetic damage detected in human cells. One major oncogenesis process is activation of proto-oncogenes by point mutations or chromosomal translocation. There are substantial evidence that indicates that the loss of heterozygosity of certain chromosomes is involved in human cancerogenesis. Our study aimed to elicit the possible association between cancer and DNA and cytogenetic abnormalities induced in lymphocytes of people bearing various categories of skin cancer cells. Fresh blood was collected by venipuncture from 25 individuals (including nine prior to cancer treatment). All patients were nonsmoking males, however 42.3 % of them were former smokers. Blood samples were divided into two parts and in the first part of samples cytogenetic studies were performed immediately, while from the second part lymphocytes were isolated ...

2004-11-01

340

Transport of symmetric mass region fission products at the Oklo natural reactors  

International Nuclear Information System (INIS)

The isotopic composition of Pd, Ag, Cd and Te has been measured by solid source mass spectrometry for four samples from reactor zones 2, 3-4, 5-6 and 7, and from four host rock samples external to the reactor zones from the Oklo mine site. The concentrations of these elements have also been determined in the eight samples using the stable isotope dilution technique. Cumulative fission yields have been derived from the reactor zone samples after correcting where necessary for the terrestrial component of the element concerned. It has been shown that fission-produced Pd and Te are retained almost in their entirety in the uraninite reactor zone samples, whereas a significant fraction of fission-produced Ag and Cd have migrated from the reactor zones. Fission product Cd is observed in the host rock samples, whereas no strong evidence of fission-produced Ag could be found. This the ...

1984-01-01

341

DISTRIBUTION AND RANGE OF RADIONUCLIDE SORPTION COEFFICIENTS IN A SAVANNAH RIVER SITE SUBSURFACE: STOCHASTIC MODELING CONSIDERATIONS  

Energy Technology Data Exchange (ETDEWEB)

The uncertainty associated with the sorption coefficient, or K{sub d} value, is one of the key uncertainties in estimating risk associated with burying low-level nuclear waste in the subsurface. The objective of this study was to measure >648 K{sub d} values and provide a measure of the range and distribution (normal or log-normal) of radionuclide K{sub d} values appropriate for the E-Area disposal site, within the Savannah River Site, near Aiken South Carolina. The 95% confidence level for the mean K{sub d} was twice the mean in the Aquifer Zone (18-30.5 m depth), equal to the mean for the Upper Vadose Zone (3.3-10 m depth), and half the mean for the Lower Vadose Zone (3.10-18 m depth). The distribution of K{sub d} values was log normal in the Upper Vadose Zone and Aquifer Zone, and normal in the Lower Vadose Zone. To our knowledge, this is the first ...

2010-01-11

342

INTERACTING BINARIES WITH ECCENTRIC ORBITS. III. ORBITAL EVOLUTION DUE TO DIRECT IMPACT AND SELF-ACCRETION  

International Nuclear Information System (INIS)

The rapid circularization and synchronization of the stellar components in an eccentric binary system at the onset of Roche lobe overflow is a fundamental assumption common to all binary stellar evolution and population synthesis codes, even though the validity of this assumption is questionable both theoretically and observationally. Here we calculate the evolution of the orbital elements of an eccentric binary through the direct three-body integration of a massive particle ejected through the inner Lagrangian point of the donor star at periastron. The trajectory of this particle leads to three possible outcomes: direct accretion onto the companion star within a single orbit, self-accretion back onto the donor star within a single orbit, or a quasi-periodic orbit around the companion star, possibly leading to the formation of a disk. We calculate the secular evolution of the binary orbit in the first two cases and conclude ...

2010-11-20

343

Evolution of nitrogen oxide(s) during in vivo nitrate reductase assay of soybean leaves  

Energy Technology Data Exchange (ETDEWEB)

Studies were conducted to quantitate the evolution of nitrogen oxides (NO/sub (x)/) from soybean (Glycine max (L.) Merr.) leaves during in vivo nitrate reductase (NR) assays with aerobic and anaerobic gas purging. Anaerobic gas purging (N/sub 2/ and argon) consistently resulted in greater NO/sub (x)/ evolution than did aerobic gas purging (air and O/sub 2/). The evolution of NO/sub (x)/ was dependent on gas flow rate and on NO/sub 2//sup -/ formation in the assay medium; although a threshold level of NO/sub 2//sup -/ appeared to exist beyond which the rate of NO/sub (x)/ evolution did not increase further. The loss of NO/sub (x)/ from in vivo NR assays under gas purging explains partially, but not stoichiometrically, the decrease of NO/sub 2//sup -/ accumulation in in vivo NR assay medium with young soybean leaves. The lack of stoichiometry between NO/sub (x)/ evolution and apparent ...

1981-12-01

344

Durability of cement-based materials: modeling of the influence of physical and chemical equilibria on the microstructure and the residual mechanical properties; Durabilite des materiaux cimentaires: modelisation de l'influence des equilibres physico-chimiques sur la microstructure et les proprietes mecaniques residuelles  

Energy Technology Data Exchange (ETDEWEB)

A large part of mechanical and durability characteristics of cement-based materials comes from the performances of the hydrated cement, cohesive matrix surrounding the granular skeleton. Experimental studies, in situ or in laboratory, associated to models, have notably enhanced knowledge on the cement material and led to adapted formulations to specific applications or particularly aggressive environments. Nevertheless, these models, developed for precise cases, do not permit to specifically conclude for other experimental conclusions. To extend its applicability domain, we propose a new evolutive approach, based on reactive transport expressed at the microstructure scale of the cement. In a general point of view, the evolution of the solid compounds of the cement matrix, by dissolutions or precipitations, during chemical aggressions can be related to the pore solution evolution, and this one relied to the ionic exchanges ...

2004-09-15

345

Time reversible evolution via nonadiabatic coupling in adiabatic dark subspace  

British Library Electronic Table of Contents (United Kingdom)

We propose a method for the creation of arbitrary superposition of N atomic states using generalized stimulated Raman adiabatic passage (STIRAP) techniques with laser fields coupling each one of N lower states to a single upper state in a Formula Not Shown -level atomic system. Formula Not Shown dark states that are composed of N lower states span a dark subspace. In the adiabatic limit, the dark and bright subspaces are decoupled, thus the nonadiabatic interaction within this dark subspace dominates the evolution of the system. Different from general methods to create our required coherent superposition state, in a reverse way, here we consider the required state as the starting point of evolution dynamics, and utilize laser fields to drive it into a single lower state step by step. Time ...

2010-01-01

346

The evolution of the Cepheid stars  

International Nuclear Information System (INIS)

The evolution of intermediate and high mass stars is reviewed focusing on the interpretation of Pop I Cepheids. First, a summary is given of the classical results of stellar evolution theory for the main evolutionary phases (main sequence and core He-burning) all over the HR diagram, putting into evidence the various points of disagreement with current observational data. Second, models incorporating the effect of convective overshoot, are reviewed, and studies are presented on the rich, young clusters in the Large Magellanic Cloud, in which the models are compared with the observational data. Arguments are given to favor the adoption of models with convective overshoot instead of the classical ones. Third, new results are presented for pulsational models of the Cepheid stars, and the shape of the instability strip in the HR diagram, the number frequency-period distribution, and the mass discrepancy are discussed. 81 refs.

1990-05-28

347

Role of the radiation pressure gradient in giant and supergiant star evolution  

Science.gov (United States)

Since some of the earliest evolutionary calculations it has been found that post main sequence stars become red giants (e.g. Sandage and Schwarzschild, 1952). However the exact physical processes that lead to and determine the rate of redward evolution are not completely understood. We hypothesized that the redward evolution might be due to an increase in radiation pressure somewhere in the star that causes the layers above it to be pushed outward, resulting in an expanded envelope and a cooler surface temperature. If the radiative luminosity somewhere in the star approached the Eddington limit, the outer layers would obviously expand. However, due to the presence of gas pressure, the critical value for expansion would be somewhat less than the Eddington limit.

1983-10-07

348

Reply to comment on "A simple model for the short-time evolution of near-surface current and temperature profiles"  

CERN Document Server

This is our response to a comment by Walter Eifler on our paper `A simple model for the short-time evolution of near-surface current and temperature profiles' (arXiv:physics/0503186, accepted for publication in Deep-Sea Research II). Although Eifler raises genuine issues regarding our model's validity and applicability, we are nevertheless of the opinion that it is of value for the short-term evolution of the upper-ocean profiles of current and temperature. The fact that the effective eddy viscosity tends to infinity for infinite time under a steady wind stress may not be surprising. It can be interpreted as a vertical shift of the eddy viscosity profile and an increase in the size of the dominant turbulent eddies under the assumed conditions of small stratification and infinite water depth.

2005-01-01

349

Renormalization Group Running of Lepton Mixing Parameters in See-Saw Models with $S_4$ Flavor Symmetry  

CERN Document Server

We study the renormalization group running of the tri-bimaximal mixing predicted by the two typical $S_4$ flavor models at leading order. Although the textures of the mass matrices are completely different, the evolution of neutrino mass and mixing parameters is found to display approximately the same pattern. For both normal hierarchy and inverted hierarchy spectrum, the quantum corrections to both atmospheric and reactor neutrino mixing angles are so small that can be neglected. The evolution of solar mixing angle $\\theta_{12}$ depends on $\\tan\\beta$ and mass spectrum, the deviation from its tri-bimaximal value could be large. Taking into account the renormalization group running effect, the neutrino spectrum is constrained by experimental data on $\\theta_{12}$ and the inverted hierarchy spectrum is disfavored for large $\\tan\\beta$. The evolution of light neutrino masses is approximately described by a common ...

2010-01-01

350

Phase Information and the Evolution of Cosmological Density Perturbations  

CERN Document Server

The Fourier transform of cosmological density perturbations can be represented in terms of amplitudes and phases for each Fourier mode. We investigate the phase evolution of these modes using a mixture of analytical and numerical techniques. Using a toy model of one-dimensional perturbations evolving under the Zel'dovich approximation as an initial motivation, we develop a statistic that quantifies the information content of the distribution of phases. Using numerical simulations beginning with more realistic Gaussian random-phase initial conditions, we show that the information content of the phases grows from zero in the initial conditions, first slowly and then rapidly when structures become non-linear. This growth of phase information can be expressed in terms of an effective entropy: Gaussian initial conditions are a maximum entropy realisation of the initial power spectrum, gravitational evolution decreases the phase entropy. We show that ...

2000-01-01

351

Nonlinear evolution of protostellar disks and light modulations in young stellar objects  

International Nuclear Information System (INIS)

An evolutionary model of dynamical processes in protostellar disks is described and illustrated with graphs of typical results. The effective transport mechanisms are discussed, including thermal convection, nonaxisymmetric gravitational instabilities in the outer regions of disks, and wave propagation. Consideration is then given to the stages of dynamical evolution, FU Ori outburst phenomena, unsteady accretion-disk flows, and nonlinear feedback as a mechanism to modulate mass transfer. The simulations show that mass redistribution is determined by angular-momentum transfer, which in turn is regulated by the effective viscosity generated by convectively driven turbulence. Significant mass transfer occurs as a result of mixing of infalling material with disk gas and is affected by the tidal torque associated with the growth of nonaxisymmetric disturbances in the outer disk. The time scale for disk evolution is found to be about 1 Myr. 72 refs.

1989-10-05

352

Late cenozoic evolution of Fortymile Wash: Major change in drainage pattern in the Yucca Mountain, Nevada region during late miocene volcanism  

International Nuclear Information System (INIS)

The site characterization of Yucca Mountain, NV as a potential high level nuclear waste repository includes study of the surficial deposits as a record of the paleoenvironmental history of the Yucca Mountain region. An important aspect of this history is an understanding of the evolution of paleogeography leading to establishment of the present drainage pattern. Establishment of drainage basin evolution is needed before geomorphic response to paleoclimate and tectonics can be assessed, because a major change in drainage basin geometry can predominantly affect the sedimentary record. Because alluvial aquifers are significant to regional hydrology, a major change in surface drainage resulting in buried alluvium could have hydrogeologic significance. In this paper, we report on geologic evidence for a major modification in surface drainage pattern in the Yucca Mountain region, resulting in the probable establishment of the Fortymile Wash drainage ...

1994-05-22

353

Influence of Population III stars on cosmic chemical evolution  

British Library Electronic Table of Contents (United Kingdom)

ABSTRACT New observations from the Hubble Ultra Deep Field suggest that the star formation rate at Formula Not Shown drops off faster than previously thought. Using a newly determined star formation rate for the normal mode of Population II/I (PopII/I) stars, including this new constraint, we compute the Thomson scattering optical depth and find a result that is marginally consistent with Wilkinson Microwave Anisotropy Probe 5 results. We also reconsider the role of Population III (PopIII) stars in light of cosmological and stellar evolution constraints. While this input may be needed for reionization, we show that it is essential in order to account for cosmic chemical evolution in the early universe. We investigate the consequences of PopIII stars on the local metallicity distribution fu...

2009-01-01

354

Evolutionary implications of morphogenesis and molecular patterning of the blind gut in the planarian Schmidtea polychroa  

British Library Electronic Table of Contents (United Kingdom)

The formation of a through-gut was a key innovation in the evolution of metazoans. There is still controversy regarding the origin of the anus and how it may have been either gained or lost during evolution in different bilaterian taxa. Thus, the study of groups with a blind gut is of great importance for understanding the evolution of this organ system. Here, we describe the morphogenesis and molecular patterning of the blind gut in the sexual triclad Schmidtea polychroa. We identify and analyze the expression of goosecoid, commonly associated with the foregut, and the GATA, ParaHox and T-box genes, members of which commonly are associated with gut regionalization. We show that GATA456a is expressed in the blind gut of triclads, while GATA456b is localized in dorsal parenchymal cells. Goo...

2011-01-01

355

Close binaries containing Supermassive Black Holes  

British Library Electronic Table of Contents (United Kingdom)

We consider the evolution of binary systems formed by a Supermassive Black Hole (SMBH) residing in the center of a galaxy or a globular cluster and a star in its immediate vicinity. The star is assumed to fill its Roche lobe, and the SMBH accretes primarily the matter of this star. The evolution of such a system is mainly determined by the same processes as for an ordinary binary. The main differences are that the donor star is irradiated by hard radiation emitted during accretion onto the SMBH; in a detached system, nearly all the donor wind is captured by the black hole, which strongly affects the evolution of the semi-major axis; it is not possible for companions of the most massive SMBHs to fill their Roche lobes, since the corresponding orbital separations are smaller than the radius ...

2010-01-01

356

Biodiversity, agriculture, and livelihoods: Co-evolution and competition in an Andean-Amazonian watershed  

Environmental Research Database

Objectives1. To create a strong, interdisciplinary evidence base about the relationships linking ecosystems, agrobiodiversity, wild biodiversity, and sustainable livelihoods, including the use of trade-off analysis (modeling the relationships between agricultural productivity, levels of biodiversity, and ecosystem resilience); crop evolutionary studies (wild relative/crop interactions) and socioeconomic, cultural, and nutritional studies of the contribution of biodiversity to different livelihoods asset [continued...]DescriptionAgriculture, ecosystems, and humans have co-evolved over millennia in the Andean-Amazonian region, creating the richest of all Vavilov centers of crop origin and diversity. The conservation of a wide range of domesticated crops and landraces (i.e., indigenous, ancestral varieties or cultivars that are distinct, uniform, and stable) and their co-evolution with crop wild relatives (CRW) has been essential for food security, adaptation to ...

2011-01-31

357

A unified framework for biological evolution and stochastic quantization  

CERN Document Server

We investigate the profound relation between the equations of biological evolution and quantum mechanics by writing a biologically inspired equation for the stochastic dynamics of an ensemble of particles. Interesting behavior is observed which is related to a new type of stochastic quantization. We find that the probability distribution of the ensemble of particles can be decomposed into eigenfunctions associated to a discrete spectrum of eigenvalues. In absence of interactions between the particles, the out-of-equilibrium dynamics asymptotically relaxes towards the fundamental state. This phenomenon can be related with the Fisher theorem in biology. On the contrary, in presence of scattering processes the evolution reaches a steady state in which the distribution of the ensemble of particles is characterized by a Bose-Einstein statistics. In order to show a concrete example of this stochastic quantization we have solved explicitly the case in ...

2010-01-01

358

A Lamarckian Hybrid of Differential Evolution and Conjugate Gradients for Neural Network Training  

British Library Electronic Table of Contents (United Kingdom)

The paper describes two schemes that follow the model of Lamarckian evolution and combine differential evolution (DE), which is a population-based stochastic global search method, with the local optimization algorithm of conjugate gradients (CG). In the first, each offspring is fine-tuned by CG before competing with their parents. In the other CG is used to improve both parents and offspring in a manner that is completely seamless for individuals that survive more than one generation. Experiments involved training weights of feed-forward neural networks to solve three synthetic and four real-life problems. In six out of seven cases the DE?CG hybrid, which preserves and uses information on each solution?s local optimization process, outperformed two recent variants of DE.

2010-01-01

359

X-ray stars in globular clusters  

Science.gov (United States)

The properties and kinetics of x-ray stars in globular clusters are described. Locations, configurations, star evolution, massive close binary systems, various mechanisms, and the x-ray burster properties are included. (JFP)

1977-10-01

360

Worlds within worlds: evolution of the vertebrate gut microbiota  

UK PubMed Central (United Kingdom)

Here we use published 16S rRNA gene sequences to compare the bacterial assemblages associated with humans, other mammals, other metazoa, and free-living microbial communities spanning a range...Full Text Available

2008-10-01

361

Underlying Principles of Natural Selection in Network Evolution: Systems Biology Approach  

UK PubMed Central (United Kingdom)

Systems biology is a rapidly expanding field that integrates diverse areas of science such as physics, engineering, computer science, mathematics, and biology toward the goal of elucidating the underlying...Full Text Available

362

Tool Life Prediction for Ceramic Tools in Intermittent Turning of Hardened Steel Based on Damage Evolution Model  

Science.gov (United States)

Al2O3-based ceramic is one of the most widely used materials for tools employed in hardened steel turning applications due to its high hardness, wear resistance, heat resistance and chemical stability. The objective of this work is to predict the lives of Al2O3-(W, Ti)C ceramic tools in intermittent turning of hardened AISI 1045 steel by means of damage evolution model taking into account the mechanical loading and thermal effect in the cutting process. A damage evolution model analyzing the RVE with uniformly distributed interacting cracks is constructed based on micromechanics. The calculated results of the proposed damage evolution model are compared with the lives of two kinds of Al2O3-(W, Ti)C ceramic tools obtained through experiments. It is found that the proposed model can be used to predict the lives of the ceramic cutting tools in intermittent turning operation.

2011-07-01

363

The mode and tempo of genome size evolution in eukaryotes  

UK PubMed Central (United Kingdom)

Eukaryotic genome size varies over five orders of magnitude; however, the distribution is strongly skewed toward small values. Genome size is highly correlated to a number of phenotypic traits, suggesting...Full Text Available

2007-05-01

364

The evolution of fossoriality and the adaptive role of horns in the Mylagaulidae (Mammalia: Rodentia)  

UK PubMed Central (United Kingdom)

Ceratogaulus, a member of the extinct fossorial rodent clade Mylagaulidae, is the only known rodent with horns and the smallest known horned mammal. The function of the large, dorsally...Full Text Available

2005-08-22

365

The erratic mitochondrial clock: variations of mutation rate, not population size, affect mtDNA diversity across birds and mammals  

UK PubMed Central (United Kingdom)

BackgroundDuring the last ten years, major advances have been made in characterizing and understanding the evolution of mitochondrial DNA, the most popular marker of molecular biodiversity....Full Text Available

366

The Redshift Evolution of Wet, Dry, and Mixed Galaxy Mergers from Close Galaxy Pairs in the DEEP2 Galaxy Redshift Survey  

CERN Document Server

We study the redshift evolution of galaxy pair fractions and merger rates for different types of galaxies using kinematic pairs selected from the DEEP2 Redshift Survey. Parameterizing the evolution of the pair fraction as (1+z)^{m}, we find that the companion rate increases mildly with redshift with m = 0.41+-0.20 for all galaxies with -21 < M_B^{e} < -19. Blue galaxies show slightly faster evolution in the blue companion rate with m = 1.27+-0.35 while red galaxies have had fewer red companions in the past as evidenced by the negative slope m = -0.92+-0.59. We find that at low redshift the pair fraction within the red sequence exceeds that of the blue cloud, indicating a higher merger probability among red galaxies compared to that among the blue galaxies. With further assumptions on the merger time scale and the fraction of pairs that will merge, the galaxy major merger rates for 0.1 < z <1.2 are estimated to ...

2008-01-01

367

The Medical Home Concept and Congenital Adrenal Hyperplasia: A Comfortable Habitat!  

UK PubMed Central (United Kingdom)

Patient-centered interdisciplinary health care for children with chronic medical disorders represents an evolution from the traditional “stop and go” treatment for acute illnesses. This...Full Text Available

2010-01-01

368

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

369

Selecting Folded Proteins from a Library of Secondary Structural Elements  

UK PubMed Central (United Kingdom)

A protein evolution strategy is described by which double-stranded DNA fragments encoding defined E. coli protein secondary structural elements (α-helices, β-strands...Full Text Available

2008-01-09

370

Sciiientttiiifffiiic apaciiittty uiiillldiiing nhancementtt fffor ustttaiiinabllle evelllopmenttt iiin evelllopiiing ountttriiies  

Wastenet

Buizer, Arizona State University, USA; Gernot Klepper, Kiel Institute of World Economics, ...der Leeuw School for Human Evolution and Social Change, Arizona State University, USA

371

SN1987A: The supernova of a lifetime  

Energy Technology Data Exchange (ETDEWEB)

The current status of cosmological observations is presented; and the light curves and radiation spectra from supernova SN1987A are used in comparison between expected and observed universal nucleosynthesis and star evolution data./aip/.

1988-09-20

372

Reduced-Median-Network Analysis of Complete Mitochondrial DNA Coding-Region Sequences for the Major African, Asian, and European Haplogroups  

UK PubMed Central (United Kingdom)

The evolution of the human mitochondrial genome is characterized by the emergence of ethnically distinct lineages or haplogroups. Nine European, seven Asian (including Native American), and three African...Full Text Available

2002-05-01

373

Reciprocal Silencing, Transcriptional Bias and Functional Divergence of Homeologs in Polyploid Cotton (Gossypium)  

UK PubMed Central (United Kingdom)

Polyploidy is an important force in the evolution of flowering plants. Genomic merger and doubling induce an extensive array of genomic effects, including immediate and long-term alterations in the...Full Text Available

2009-06-01

374

Rapid evolution of sessility in an endemic species flock of the freshwater bivalve Corbicula from ancient lakes on Sulawesi, Indonesia  

UK PubMed Central (United Kingdom)

The fauna of ancient lakes frequently contains taxa with highly derived morphologies that resulted from in situ radiation of lacustrine lineages with high antiquity. We employed a molecular...Full Text Available

2006-03-22

375

Rab protein evolution and the history of the eukaryotic endomembrane system  

UK PubMed Central (United Kingdom)

Spectacular increases in the quantity of sequence data genome have facilitated major advances in eukaryotic comparative genomics. By exploiting homology with classical model organisms, this makes possible...Full Text Available

2010-10-01

376

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

UK PubMed Central (United Kingdom)

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

377

Plasma Electric Potential Evolution at the Core and Edge of the TJ-II Stellarator and T-10 Tokamak  

International Nuclear Information System (INIS)

In this article are presented main results on electric potential investigations in stellarator/torsatron TJ-II and tokamak T-10 in a comparable regimes of device operation.

2006-01-01

378

Parallel Evolution of a Type IV Secretion System in Radiating Lineages of the Host-Restricted Bacterial Pathogen Bartonella  

UK PubMed Central (United Kingdom)

Adaptive radiation is the rapid origination of multiple species from a single ancestor as the result of concurrent adaptation to disparate environments. This fundamental evolutionary process is considered...Full Text Available

2011-02-01

379

Ontological realism: A methodology for coordinated evolution of scientific ontologies  

UK PubMed Central (United Kingdom)

Since 2002 we have been testing and refining a methodology for ontology development that is now being used by multiple groups of researchers in different life science domains. Gary Merrill,...Full Text Available

2010-11-15

380

Observatory reports  

Energy Technology Data Exchange (ETDEWEB)

This review covers research done at Lawrence Livermore National Laboratory under DOE contract. Areas of research are as follows: star evolution supernovae, and nucleosynthesis; stellar atmospheres and winds; galaxies and interstellar space; and high-energy astrophysics.

1983-01-01

381

Observatory report  

Energy Technology Data Exchange (ETDEWEB)

This review covers research done at Lawrence Livermore National Laboratory in the fields of astronomy and astrophysics. The research areas mentioned are as follows: star evolution, supernovae, and nucleosynthesis; stellar atmospheres and winds; galaxies and the interstellar medium; and high-energy astrophysics.

1984-01-01

382

Nucleon resonance studies in phenomenological analysis of the CLAS  

Energy Technology Data Exchange (ETDEWEB)

First comprehensive data on the evolution of nucleon resonance photocouplings with photon virtuality Q{sup 2} are presented for excited proton states in the mass range from 1.4 to 2.0 GeV.

2006-07-01

383

Neutron star collisions and the r-process  

Energy Technology Data Exchange (ETDEWEB)

It is shown that a natural consequence of the binary pulsar's evolution is a neutron star collision. Such a collision is expected to eject neutron-rich matter of an r-process character. Taking reasonable estimates for the number of such events over the history of the galaxy, it may be that they account for all of the r-process nuclei.

1982-01-01

384

Multivesicular bodies in the enigmatic amoeboflagellate Breviata anathema and the evolution of ESCRT 0  

UK PubMed Central (United Kingdom)

Endosomal sorting complexes required for transport (ESCRTs) are heteromeric protein complexes required for multivesicular body (MVB) morphogenesis. ESCRTs I, II, III and III-associated are ubiquitous...Full Text Available

2011-02-15

385

Lineage-specific co-evolution of the Egf receptor/ligand signaling system  

UK PubMed Central (United Kingdom)

BackgroundThe epidermal growth factor receptor (Egfr) with its numerous ligands has fundamental roles in development, cell differentiation and physiology. Dysfunction of the receptor-ligand...Full Text Available

386

Jane Powell  

Wastenet

...The Political Evolution of the Landfill Tax in the UK wm-1996-03 Green Taxes, Waste Management and Political Economy 1995 ^ Top ...on civil engineering Lifecycle assessment - an overlooked opportunity Refereed Journal Articles: Green taxes, waste management and political economy Reports: Environmental cost benefit ...

387

Integrase-directed recovery of functional genes from genomic libraries  

UK PubMed Central (United Kingdom)

Large population sizes, rapid growth and 3.8 billion years of evolution firmly establish microorganisms as a major source of the planet's biological and genetic diversity. However, up to 99% of the...Full Text Available

2009-09-01

388

Inferring Stabilizing Mutations from Protein Phylogenies: Application to Influenza Hemagglutinin  

UK PubMed Central (United Kingdom)

One selection pressure shaping sequence evolution is the requirement that a protein fold with sufficient stability to perform its biological functions. We present...Full Text Available

2009-04-01

389

Induction and transmission of Bacillus thuringiensis tolerance in the flour moth Ephestia kuehniella  

UK PubMed Central (United Kingdom)

The use of Bacillus thuringiensis (Bt) endotoxins to control insect vectors of human diseases and agricultural pests is threatened by the possible evolution of resistance in major pest...Full Text Available

2004-03-02

390

Identification of the Response Parameters of a Geothermal Field During a Non-Isothermal Short Time Water Injection Test.  

Science.gov (United States)

Various methods to analyse the effect of a non-isotherme water injection on the pressure evolution during a test on a double geothermal well are investigated. Then, several types of injection test are simulated with experimental data to examine the condit...

1983-01-01

391

How do planetary nebulae evolve  

Energy Technology Data Exchange (ETDEWEB)

This article throws light on an only recently understood but important development of star evolution - that of the occurrence of planetary nebulae. The process is controlled by thermonuclear physics and gravitation and now and again greatly influenced by mass loss.

1982-01-01

392

How Protein Stability and New Functions Trade Off  

UK PubMed Central (United Kingdom)

Numerous studies have noted that the evolution of new enzymatic specificities is accompanied by loss of the protein's thermodynamic stability (ΔΔG), thus suggesting...Full Text Available

2008-02-01

393

Honing the Dagger: The formation of a Standing Joint Special Operations Task Force Headquarters.  

Science.gov (United States)

This monograph explores an alternative way of providing a JSOTF headquarters to the Joint Force Commander. Beginning with a history of joint SOF doctrine, the monograph outlines the evolution of special operations command and control and the subsequent ne...

2005-01-01

394

Hominin life history: reconstruction and evolution  

UK PubMed Central (United Kingdom)

In this review we attempt to reconstruct the evolutionary history of hominin life history from extant and fossil evidence. We utilize demographic life history theory and distinguish life history variables,...Full Text Available

2008-04-01

395

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

396

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

397

Genomic Content of Bordetella pertussis Clinical Isolates Circulating in Areas of Intensive Children Vaccination  

UK PubMed Central (United Kingdom)

BackgroundThe objective of the study was to analyse the evolution of Bordetella pertussis population and the influence of herd immunity in different areas of the...Full Text Available

398

Examples of degenerated matter in astrophysics: white dwarf and neutron stars  

Energy Technology Data Exchange (ETDEWEB)

Main features of star evolution are recalled. Then the general structure of white dwarf stars is examined. From the equation of state of an electron gas completely degenerated are deduced: mechanical equilibrium, Viriel theorem, mass-radius relationship and Chandrasekhar limit. These results are applied to neutron stars.

1982-06-01

399

Evolutionary history of a specialized P450 propane monooxygenase  

UK PubMed Central (United Kingdom)

SummaryThe evolutionary pressures that shaped the specificity and catalytic efficiency of enzymes can only be speculated. While directed evolution experiments show that new functions...Full Text Available

2008-11-28

400

Evolutionary Trajectories of Beta-Lactamase CTX-M-1 Cluster Enzymes: Predicting Antibiotic Resistance  

UK PubMed Central (United Kingdom)

Extended-spectrum beta-lactamases (ESBL) constitute a key antibiotic-resistance mechanism affecting Gram-negative bacteria, and also an excellent model for studying evolution in real time. A shift in...Full Text Available

2010-01-01

401

Evolution of the redox function in mammalian Apurinic/apyrimidinic endonuclease  

UK PubMed Central (United Kingdom)

Human apurinic/apyrimidinic endonuclease (hApe1) encodes two important functional activities: an essential base excision repair (BER) activity and a redox activity that regulates expression...Full Text Available

2008-08-25

402

Evolution of feeding specialization in Tanganyikan scale-eating cichlids: a molecular phylogenetic approach  

UK PubMed Central (United Kingdom)

BackgroundCichlid fishes in Lake Tanganyika exhibit remarkable diversity in their feeding habits. Among them, seven species in the genus Perissodus are known for...Full Text Available

403

Evolution of age at menarche and at onset of regular cycling in a large cohort of French women  

UK PubMed Central (United Kingdom)

BackgroundEarly exposure to ovarian hormones is considered to increase breast cancer incidence. The age at which the ovaries become functional is thus important.Full Text Available

2002-01-01

404

Evolution of Thermal Response Properties in a Cold-Activated TRP Channel  

UK PubMed Central (United Kingdom)

Animals sense changes in ambient temperature irrespective of whether core body temperature is internally maintained (homeotherms) or subject to environmental variation (poikilotherms). Here we show...Full Text Available

405

Evolution of DMY, a newly emergent male sex-determination gene of medaka fish.  

UK PubMed Central (United Kingdom)

The Japanese medaka fish Oryzias latipes has an XX/XY sex-determination system. The Y-linked sex-determination gene DMY is a duplicate of the autosomal gene DMRT1, which encodes a DM-domain-containing...Full Text Available

2004-04-01

406

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

UK PubMed Central (United Kingdom)

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

2010-09-01

407

Evidence for modular evolution in a long-tailed pterosaur with a pterodactyloid skull  

UK PubMed Central (United Kingdom)

The fossil record is a unique source of evidence for important evolutionary phenomena such as transitions between major clades. Frustratingly, relevant fossils are still comparatively rare, most transitions...Full Text Available

2010-02-07

408

Economic regulation and hospital behavior: the effects on medical staff organization and hospital-physician relationships.  

UK PubMed Central (United Kingdom)

New forms of payment, growing competition, the continued evolution of multiunit hospital systems, and associated forces are redefining the fundamental relationship between hospitals and physicians....Full Text Available

1985-12-01

409

EVOLUTION OF MASSIVE STARS WITH PULSATION-DRIVEN SUPERWINDS DURING THE RED SUPERGIANT PHASE  

International Nuclear Information System (INIS)

Pulsations driven by partial ionization of hydrogen in the envelope are often considered important for driving winds from red supergiants (RSGs). In particular, it has been suggested by some authors that the pulsation growth rate in an RSG can be high enough to trigger an unusually strong wind (or a superwind), when the luminosity-to-mass ratio becomes sufficiently large. Using both hydrostatic and hydrodynamic stellar evolution models with initial masses ranging from 15 to 40 M_s_u_n, we investigate (1) how the pulsation growth rate depends on the global parameters of supergiant stars and (2) what would be the consequences of a pulsation-driven superwind, if it occurred, for the late stages of massive star evolution. We suggest that such a superwind history would be marked by a runaway increase, followed by a sudden decrease, of the wind's mass-loss rate. The impact on the late evolution of massive stars would be ...

2010-07-01

410

Dynamical evolution driven by bars and interactions Input from numerical simulations  

CERN Document Server

We discuss the evolution of a disc galaxy due to the formation of a bar and, subsequently, a peanut. After the formation stage there is still considerable evolution, albeit slower. In purely stellar cases the pattern speed of the bar decreases with time, while its amplitude grows. However, if a considerable gaseous component is present in the disc, the pattern speed may increase with time, while the bar strength may decrease. In some cases the gas can be brought sufficiently close to the center to create a strong central concentration, which, in turn, may modify the properties of the bar. More violent evolution can take place during interactions, so that some disc substructures can be either formed or destroyed in a time scale which is small compared to a Hubble time. These include spirals, bars, bridges, tails, rings, thick discs and bulges. In some cases interactions may lead to mergings. We briefly review comparisons of ...

2002-01-01

411

Dynamic nucleation of new grains in magnesium alloy during hot deformation  

Energy Technology Data Exchange (ETDEWEB)

Microstructure evolution under hot deformation was investigated in compression of a magnesium alloy AZ31 at 673 K (0.73T{sub m}). Two kinds of samples were machined along the parallel and transverse direction of the extruded rods. New fine grains are evolved at corrugated grain boundaries at low strains and developed rapidly in grain interiors in the medium range of strain, finally leading to a roughly full evolution of equiaxial fine grains. Kink bands are evolved at corrugated grain boundaries and in grain interiors at low strains. The boundary misorientation of kink band increases rapidly with increasing strain. These characteristics of new grain evolution process are not changed by the orientation of the samples, while the flow behaviors clearly depend on it. It is concluded that new grain evolution can be controlled by a deformation-induced continuous reaction resulting in grain fragmentation by ...

2003-07-01

412

Duplication and Diversification of the Hypoxia-Inducible IGFBP-1 Gene in Zebrafish  

UK PubMed Central (United Kingdom)

BackgroundGene duplication is the primary force of new gene evolution. Deciphering whether a pair of duplicated genes has evolved divergent functions is often challenging. The zebrafish...Full Text Available

413

Doublet III vacuum vessel neutral beam armor  

Science.gov (United States)

The evolution of the Doublet III neutral beam armor is followed from the initial design of a radiation cooled metallic tile to the present actively cooled graphite design. Results of the thermal and stress analyses that dictated the present design are reviewed.

1979-11-01

414

Dissipative particle swarm optimization  

CERN Document Server

A dissipative particle swarm optimization is developed according to the self-organization of dissipative structure. The negative entropy is introduced to construct an opening dissipative system that is far-from-equilibrium so as to driving the irreversible evolution process with better fitness. The testing of two multimodal functions indicates it improves the performance effectively

2005-01-01

415

Dissecting the Genetic Components of Adaptation of Escherichia coli to the Mouse Gut  

UK PubMed Central (United Kingdom)

While pleiotropic adaptive mutations are thought to be central for evolution, little is known on the downstream molecular effects allowing adaptation to complex ecologically relevant environments. Here...Full Text Available

2008-01-01

416

Developmental plasticity and the evolution of animal complex life cycles  

UK PubMed Central (United Kingdom)

Metazoan life cycles can be complex in different ways. A number of diverse phenotypes and reproductive events can sequentially occur along the cycle, and at certain stages a variety of developmental...Full Text Available

2010-02-27

417

Comparative genomics of the bacterial genus Listeria: Genome evolution is characterized by limited gene acquisition and limited gene loss  

UK PubMed Central (United Kingdom)

BackgroundThe bacterial genus Listeria contains pathogenic and non-pathogenic species, including the pathogens L. monocytogenes and L. ivanovii,...Full Text Available

418

Choosing a future for epidemiology: I. Eras and paradigms.  

UK PubMed Central (United Kingdom)

To inform choices about the future of epidemiology, the present condition of epidemiology is examined, in terms of its evolution through three eras, each demarcated by its own paradigm: (1) the era...Full Text Available

1996-05-01

419

Characterization of the Key Step for Light-driven Hydrogen Evolution in Green Algae*  

UK PubMed Central (United Kingdom)

Under anaerobic conditions, several species of green algae perform a light-dependent hydrogen production catalyzed by a special group of [FeFe] hydrogenases termed HydA. Although highly interesting...Full Text Available

2009-12-25

420

Characterization of Photosystem II Activity and Heterogeneity during the Cell Cycle of the Green Alga Scenedesmus quadricauda1  

UK PubMed Central (United Kingdom)

The photosynthetic activity of the green alga Scenedesmus quadricauda was investigated during synchronous growth in light/dark cycles. The rate of O2 evolution increased...Full Text Available

1999-06-01

421

Can Deterministic Mechanical Size Effects Contribute to Fracture and Microdamage Accumulation in Trabecular Bone?  

UK PubMed Central (United Kingdom)

Failure of bone under monotonic and cyclic loading is related to the bone mineral density, the quality of the bone matrix and the evolution of microcracks. The theory of linear elastic fracture...Full Text Available

2010-07-21

422

Boule and the Evolutionary Origin of Metazoan Gametogenesis: A Grandpa's Tale  

UK PubMed Central (United Kingdom)

The evolution of sex remains a hotly debated topic in evolutionary biology. In particular, studying the origins of the molecular mechanisms underlying sexual reproduction and gametogenesis (its fundamental...Full Text Available

423

Biochemical Conservation and Evolution of Germacrene A Oxidase in Asteraceae*  

UK PubMed Central (United Kingdom)

Sesquiterpene lactones are characteristic natural products in Asteraceae, which constitutes ∼8% of all plant species. Despite their physiological and pharmaceutical importance, the biochemistry...Full Text Available

2010-05-28

424

Big bang nucleosynthesis  

Energy Technology Data Exchange (ETDEWEB)

The concordance of standard big bang nucleosynthesis theory and the related observations of the light element isotopes (including some new higher {sup 4}He abundances) will be reviewed. Implications of BBN on chemical evolution, dark matter and constraints on particle properties will be discussed.

1999-01-01

425

Astronomical and astrophysical research activities of the Institute of Astronomy  

Energy Technology Data Exchange (ETDEWEB)

Observational work on quasars, galaxies, and stars is summarized. Theoretical studies covering stars and stellar evolution, galaxies, clusters and cosmology, high energy astrophysics the solar system and the Sun are described. (ESA)

1980-01-01

426

Are Petals Sterile Stamens or Bracts? The Origin and Evolution of Petals in the Core Eudicots  

UK PubMed Central (United Kingdom)

BackgroundThe aim of this paper is to discuss the controversial origins of petals from tepals or stamens and the links between the morphological expression of petals and floral organ...Full Text Available

2007-09-01

427

Amorphous to crystalline phase transformation in Metglas reg-sign studied by Moessbauer spectroscopy  

International Nuclear Information System (INIS)

The authors present differential scanning calorimetry (DSC) and in situ Moessbauer spectroscopy results for Metglas ribbons, to which different heat treatments were made. The Curie temperature of the amorphous phase is determined and the evolution of the magnetic field of this phase is studied as a function of temperature

1997-12-01

428

AeroSpace Information for a Changing World - NASA Technical ...  

Science.gov (United States)

Probing Neutron Star Evolution with Gamma Rays Online Source: Click to View PDF File [PDF Size: 217 KB] Author: Wijers, Ralph A. M. J. ...

429

Acetaldehyde Oxime, A Product Formed during the In Vivo Nitrate Reductase Assay of Soybean Leaves 1  

UK PubMed Central (United Kingdom)

Evolution of nitrogen oxides (NO(x), primarily as nitric oxide) from soybean (Glycine max [L.] Merr.) leaves during purged in vivo nitrate reductase assays...Full Text Available

1984-09-01

430

A new perspective on phylogeny and evolution of tetraodontiform fishes (Pisces: Acanthopterygii) based on whole mitochondrial genome sequences: Basal ecological diversification?  

UK PubMed Central (United Kingdom)

BackgroundThe order Tetraodontiformes consists of approximately 429 species of fishes in nine families. Members of the order exhibit striking morphological diversity and radiated...Full Text Available

431

A Preference for a Sexual Signal Keeps Females Safe  

UK PubMed Central (United Kingdom)

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

432

Palynostratigraphy and palaeoenvironment of the Middle Jurassic Sortehat Formation (Neill Klinter Group), Jameson Land, East Greenland  

Energy Technology Data Exchange (ETDEWEB)

The grey-black mudstones of the Sonehat Formation form part of the Middle Jurassic fill of the Jameson Land Basin in East Greenland. The formation is exposed in the southernmost part of the north south-trending, Mesozoic rift system in East Greenland that was part of the epeiric seaway betaveen East Greenland and Norway. Sedimentological observations of the Sortehat Formation indicate deposition in an offshore marine setting that was typically low energy and periodically oxygen-deficient but was influenced by storm currents on occasion. Detailed palynological studies of the Sortehat Formation have resulted in the definition of theee palynological assemblage zones recognised at four localities, namely Enhjoerningen Dal and Pelion (north Jameson Land), the type section at Sortehat (central Jameson Land) and Albuen at Neill Klinter along Hurry Inlet (south-east Jameson Land). In stratigraphic order, these zones are termed the Botryococcus ...

2003-07-01

433

CO_2 reactivity and heterogeneity of cerebral blood flow in ischemic, border zone, and normal cortex  

International Nuclear Information System (INIS)

Regional arterial CO2 tension (PaCO2) reactivity of cerebral blood flow (CBF) and the effect of PaCO2 on the spatial and temporal heterogeneity of CBF were investigated by using autoradiographically determined CBF in the rat middle cerebral artery occlusion model after a 2-h period under pentobarbital anesthesia to clarify the relation between PaCO2 reactivity, CBF heterogeneity, and the temporal cycling of CBF. PaCO2 was adjusted to one of four levels. CBF was determined in four cortical areas and white matter using the tissue fractionation of [14C]iodoantipyrine [( 14C]IAP) in combination with vessel mapping using in vivo 4% thioflavine S. Specific PaCO2 reactivity and CBF were normal in the nonischemic cortex, normal, although slightly depressed, in the border zone far from the ischemic core area, and depressed in the border zone adjacent to the ischemic core area (P less than 0.001) and the ischemic core (P less than 0.001). In normocapnic ...

434

The evolution of rigid-plastic dynamic response by mathematical programming  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a systematic approach to the automatic determination of the evolution of the rigid-plastic structural response caused by a proportional or single parameter pressure loading which varies with time in a monotonic non decreasing fashion. The frame structure is envisaged as a network, and the fundamental vectorial conditions characterising its behaviour at any instant of time are combined in a consistent manner. By considering the level of the pressure loading to be a single load parameter ranging monotonically from zero to infinity, the structural governing system may be regarded as a parametric linear complementary problem. (author). 13 refs., 2 figs.

1995-12-31

435

Spatial structure of compound dither in L/H transition  

Energy Technology Data Exchange (ETDEWEB)

To study the plasma evolution and spatial structure at the L/H transition, the double hysteresis is examined by use of the 1-dimensional transport model equations. Three mechanisms for the bipolar losses, i.e., the loss cone loss, collisional bulk viscosity loss of ions and the anomalous loss are simultaneously retained. Five-fold multiple bifurcations are found to exist at the plasma edge, similar to the previous 0-dimensional study. Double hysteresis causes a self-generated oscillation, which is attributed to the compound dither, a kind of ELMs. Spatio-temporal evolution of the compound dither is analyzed. (author)

2000-03-01

436

Simulation of flame-vortex interaction using detailed and reduced  

Energy Technology Data Exchange (ETDEWEB)

The interaction between a pair of counter-rotating vortices and a lean premixed CH{sub 4}/O{sub 2}/N{sub 2} flame ({Phi} = + 0.55) has been studied by direct numerical simulations using detailed and reduced chemical reaction schemes. Results from the complex chemistry simulation are discussed with respect to earlier experiments and differences in the simulations using detailed and reduces chemistry are investigated. Transient evolutions of the flame surface and the total heat release rate are compared and modifications in the evolution of the local flame structure are displayed. (authors) 22 refs.

1996-12-31

437

Silicidation in Pd/Si thin film junction-Defect evolution and silicon surface segregation  

Energy Technology Data Exchange (ETDEWEB)

Depth resolved positron annihilation studies on Pd/Si thin film system have been carried out to investigate silicide phase formation and vacancy defect production induced by thermal annealing. The evolution of defect sensitive S-parameter clearly indicates the presence of divacancy defects across the interface, due to enhanced Si diffusion beyond 870 K consequent to silicide formation. Corroborative glancing incidence X-ray diffraction (GIXRD), Auger electron spectroscopy (AES) and Rutherford backscattering spectrometry (RBS) have elucidated the aspects related to silicide phase formation and Si surface segregation.

2007-09-25

438

Oxygen evolution studies on perovskite films in alkaline media  

Energy Technology Data Exchange (ETDEWEB)

Thin films of La{sub 0.6}Ca{sub 0.4}CoO{sub 3} perovskite were deposited on nickel plates by thermal decomposition of the metal nitrates. The electrochemical activity of the films for oxygen evolution in KOH solutions (0.1-1 M) was investigated. The reaction order with respect to OH{sup -} ion was found to be around 0.7. The results correlate fairly well with a mechanism in which breaking of the intermediate metal-peroxide bond at the Co ion is the rate-determining step. (author) 4 figs., 4 refs.

1999-08-01

439

Overview of future evolution of the specific consumption of electric energy in the primary aluminium Brazilian industry; Perspectivas de evolucao futura do consumo especifico de energia eletrica na industria brasileira de aluminio primario  

Energy Technology Data Exchange (ETDEWEB)

This article introduces the actual artistic state in energy performance terns of the primary aluminium production in Brazil and in the world. Besides, it is evaluated the future evolution perspectives of the electrical specific consumption in the industrial sector, due to the technological innovation and determined capacity eventual expansions in the productive process. 6 refs., 2 figs, 4 tabs

1996-12-31

440

Mira variables - Pulsation, mass loss and evolution  

International Nuclear Information System (INIS)

Recent developments in the analysis of Mira atmosphere, the determination of the pulsation mode, the problem of mass loss, and the evolution of the Mira variables are covered. Model atmospheres for Mira variables, including the opacities of the molecules expected in very late M-type atmospheres are discussed. The pulsation constant for Omicron Ceti is evaluated using T(eff) = 2900 + or - 200 K, and it is concluded that Miras are fundamental mode pulsators. The importance of molecular opacity to the driving of mass loss is evaluated, and it is pointed out that the radiation pressure on molecules is not a major factor in driving mass loss from Mira. Mass loss is considered as a factor in the calculations of the periods for Mira variables. 30 refs.

1990-05-28

441

Light elements in massive single and binary stars  

CERN Document Server

We highlight the role of the light elements (Li, Be, B) in the evolution of massive single and binary stars, which is largely restricted to a diagnostic value, and foremost so for the element boron. However, we show that the boron surface abundance in massive early type stars contains key information about their foregoing evolution which is not obtainable otherwise. In particular, it allows to constrain internal mixing processes and potential previous mass transfer event for binary stars (even if the companion has disappeared). It may also help solving the mystery of the slowly rotating nitrogen-rich massive main sequence stars.

2010-01-01

442

Experimental determination of the evolution of organic matter thermal maturity indicators. Application to the Toarcian kerogens from the Paris basin  

Energy Technology Data Exchange (ETDEWEB)

The experimental maturation of an immature kerogen from the Toarcian of the Paris basin has been carried out in a confined system under pressure. The evolution of various thermal maturity parameters was plotted against the corrected organic carbon percentage chosen as a common maturity indicator and compared with data extracted from a natural series. Results show the occurrence of three distinct stages respectively characterized by the removal of oxygenated compounds, the genesis of liquid hydrocarbons and the production of gaseous hydrocarbons.

1989-03-01

443

Evolution of the white dwarf mass and spin in cataclysmic variables  

International Nuclear Information System (INIS)

We consider the spin-up of the white dwarf in non-magnetic cataclysmic variables (CVs) during secular evolution. If this is unresisted, CVs are quenched as boundary-layer emitters once the binary period has decreased by #approx# 1 hr. Angular momentum loss in nova explosions may, however, prevent the star reaching breakup. If the explosions remove (1 + #epsilon#) x the mass accreted between outbursts, values 0.5 < #approx# #epsilon# < #approx# 1 allow CVs to be modest boundary-layer emitters for most of their lifetimes. Spectral effects will limit their detection as soft X-ray sources. (author).

444

Evolution of reactivity control mechanisms for nuclear research and power reactors in India  

International Nuclear Information System (INIS)

Division of Remote Handling and Robotics (DRHR) at Bhabha Atomic Research Centre (BARC) has been working on design and development of Reactivity Control Mechanisms for Nuclear Research Reactors (Dhruva, KAMINI and recently Critical Facility of Advanced Heavy Water Reactor (AHWR)) as well as Power Reactors in India (Pressurized Heavy Water Reactors of 220 MWe at Narora and recently India's first 540 MWe PHWR Unit -1 and 2 at Tarapur). This paper gives a brief account of evolution of reactivity control mechanisms for nuclear research and power reactors in India. (author)

2009-10-01

445

Evolution of binary stars in the LMC with helium enrichment  

International Nuclear Information System (INIS)

Recent surveys of supergiants stars in the LMC indicate that the post-main-sequence region of the colour-magnitude diagram is well populated, although numerical evolution of massive stars with normal surface hydrogen indicates to the contrary. Supergiant stars having surface enrichment of helium acquired for example from a previous phase of accretion from a binary companion, however, evolve in a way so that the evolved models and observed data are consistent. We compare the available data with computed evolutionary tracks of massive stars of metallicity relevant to the LMC with and without helium-enriched envelopes and conclude that a large fraction of supergiant stars may occur in binaries. (author).

446

Effects of the variation of fundamental constants on Pop III stellar evolution  

International Nuclear Information System (INIS)

The effect of variations of the fundamental constants on the thermonuclear rate of the triple alpha reaction, "4He(#alpha##alpha#, #gamma#)"1"2C, that bridges the gap between "4He and "1"2C is investigated. We have followed the evolution of 15 and 60 M#centre dot# zero metallicity stellar models, up to the end of core helium burning. They are assumed to be representative of the first (Population III) stars. The calculated oxygen carbon abundances resulting from helium burning can then be used to constrain the variation of the fundamental constants.

2010-08-12

447

Confrontation between stellar pulsation and evolution; Proceedings of the Conference (ASP Series, Vol. 11), Bologna, Italy, May 28-31, 1990  

International Nuclear Information System (INIS)

Attention is given to the folowing topics: population I and II variable stars; LP variables, the sun, and mass determination; and predegenerate and degenerate variables. Particular papers are presented on alternative evolutionary approaches to the absolute magnitude of the RR Lyrae variables; the evolution of the Cepheid stars; nonradial pulsations in rapidly rotating Delta Scuti stars; dynamical models of dust shells around Mira variables; and pulsations of central stars of planetary nebulae.

1990-05-28

448

Common envelope evolution  

British Library Electronic Table of Contents (United Kingdom)

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

2010-01-01

449

A Nash-Moser theorem for singular evolution equations. Application to the Serre and Green-Naghdi equations  

CERN Document Server

We study the well-posedness of the initial value problem for a wide class of singular evolution equations. We prove a general well-posedness theorem under three assumptions easy to check: the first controls the singular part of the equation, the second the behavior of the nonlinearities, and the third one assumes that an energy estimate can be found for the linearized system. We allow losses of derivatives in this energy estimate and therefore construct a solution by a Nash-Moser iterative scheme. As an application to this general theorem, we prove the well-posedness of the Serre and Green-Naghdi equation and discuss the problem of their validity as asymptotic models for the water-waves equations.

2007-01-01

450

Study of the lattice parameter evolution of PWR irradiated MOX fuel by X-Ray diffraction; Etude de l'evolution du parametre cristallin des combustibles MOX irradies en rep par la methode de diffraction des rayons X  

Energy Technology Data Exchange (ETDEWEB)

Fuel irradiation leads to a swelling resulting from the formation of gaseous (Kr, Xe) or solid fission products which are found either in solution or as solid inclusions in the matrix. This phenomena has to be evaluated to be taken into account in fuel cladding Interaction. Fuel swelling was studied as a function of burn up by measuring the corresponding cell constant evolution by X-Ray diffraction. This study was realized on Mixed Oxide Fuels (MOX) irradiated in a Pressurized Water Reactor (PWR) at different burn-up for 3 initial Pu contents. Lattice parameter evolutions were followed as a function of burn-up for the irradiated fuel with and without an annealing thermal treatment. These experimental evolutions are compared to the theoretical evolutions calculated from the hard sphere model, using the fission product concentrations determined by the APPOLO computer code. Contribution of varying ...

1995-07-01

451

The highs and lows of water level : the vulnerability of coastal communities to water level change : final report on the C-CIARN Coastal Zone workshop  

Energy Technology Data Exchange (ETDEWEB)

The Coastal Zone Sector of the Canadian Climate Impact and Adaptation Research Network (C-CIARN) was established to address concerns regarding climate change in coastal areas. Coastal zones are sensitive to increases in air, sea and ground temperatures as well as to variations in sea level, precipitation, ice thickness, and storm intensity. This report presents the results of a workshop which focused on how coastal communities will be affected by climate induced water level changes, particularly sea-level rise on ocean coasts and decreasing lake levels in the Great Lakes. The workshop addressed issues such as the effects of changing water levels on coastal infrastructure, utilities, community development, and the implications of changing water levels to human safety, cultural resources, tourism, and insurance. The workshop reviewed the current state of understanding on water level fluctuations resulting from climate change. It also identified ...

2004-07-01

452

Structural transformations in Sc/Si multilayers irradiated by EUVlasers  

Energy Technology Data Exchange (ETDEWEB)

Multilayer mirrors for the extreme ultraviolet (EUV) are keyelements for numerous applications of coherent EUV sources such as newtabletop lasers and free-electron lasers. However the field ofapplications is limited by the radiation and thermal stability of themultilayers. Taking into account the growing power of EUV sources thestability of the optics becomes crucial. To overcome this problem it isnecessary to study the degradation of multilayers and try to increasetheir temporal and thermal stability. In this paper we report the resultsof detailed study of structural changes in Sc/Simultilayers when exposedto intense EUV laser pulses. Various types of surface damage such asmelting, boiling, shockwave creation and ablation were observed asirradiation fluencies increase. Cross-sectional TEM study revealed thatthe layer structure was completely destroyed in the upper part ofmultilayer, but still survived below. The layers adjacent tothe substrateremained intact even through the ...

2007-08-21

453

Stochastic combustion modeling of a direct injection diesel engine  

Energy Technology Data Exchange (ETDEWEB)

A mathematical model was developed to simulate the combustion process of a direct injection diesel engine. The model considers the key features of such a combustion process; namely fuel droplet evaporation, spray formation, mixing, ignition of heterogeneous burning of the fuel. To model mixing, great emphasis was placed on treating both large and small scale aspects of mixing, the model divides the combustion chamber into three distinct regions of air, fuel spray, and a turbulent plume that is formed once ignition occurs. The fuel spray itself is considered to be composed of multiple zones, which in turn are made of cells of equal mass and of different thermodynamic states. Micromixing of the fuel and air cells, within each zone of the jet and the turbulent plume, is then achieved by utilizing the concept of Monte Carlo stochastic coalescence dispersion technique. The frequency of such cell interactions within each zone is ...

1984-01-01

454

Prediction of fatigue crack growth behaviour of an #alpha#-#beta# titanium alloy in Paris-regime using LCF properties  

International Nuclear Information System (INIS)

A model has been developed in the recent past to predict fatigue crack growth (FCG) behaviour in the Paris-regime of various steels by employing low cycle fatigue (LCF) properties. The model forms its basis on the assumption that the cyclic damage process immediately ahead of a crack-tip, restricted in a small zone termed as process zone, is identical to those experienced in the LCF loading of a smooth specimen. Within the process zone, fatigue damage has been assumed in terms of product of stress and plastic strain which is analogous to the plastic strain energy density of the smooth specimen under fatigue loading. In this paper the model developed by Kujawski and Ellyin has been used to predict the FCG behaviour of an #alpha#-#beta# titanium alloy in the Paris-regime by employing the experimentally obtained LCF properties. The FCG behaviour thus theoretically predicted was compared with the experimentally determined FCG ...

455

Ongoing collapse of coral-reef shark populations.  

Science.gov (United States)

Marine ecosystems are suffering severe depletion of apex predators worldwide; shark declines are principally due to conservative life-histories and fisheries overexploitation. On coral reefs, sharks are strongly interacting apex predators and play a key role in maintaining healthy reef ecosystems. Despite increasing fishing pressure, reef shark catches are rarely subject to specific limits, with management approaches typically depending upon no-take marine reserves to maintain populations. Here, we reveal that this approach is failing by documenting an ongoing collapse in two of the most abundant reef shark species on the Great Barrier Reef (Australia). We find an order of magnitude fewer sharks on fished reefs compared to no-entry management zones that encompass only 1% of reefs. No-take zones, which are more difficult to enforce than no-entry zones, offer almost no protection for shark populations. Population viability ...

2006-12-01

456

OECD/NEA international Stripa project 1980-1992. Overview volume 3  

International Nuclear Information System (INIS)

The broad objective of the engineered barriers studies was to demonstrate and qualify the use of different materials and techniques for sealing water flow paths in the Stripa granite, the mine excavations and the excavation disturbed zones. As may be anticipated from the application of the observational method that forms the basis for design of geotechnical structures, the programme evolved with the finding being made at Stripa and other underground laboratories. During phase 1, the engineered barriers investigations focussed on the heat affected zone of the repository. Specifically, the response of clay buffers and the interactions between waste containers, clay buffer materials and the rock were studied. The phase 2 investigations examined the feasibility of sealing boreholes shafts and tunnels with clay sealants. The phase 3, studies of the ability to grout and seal fractured granite including the excavation disturbed ...

457

Impact of climate change on carbon cycle in freshwater ecosystems  

Energy Technology Data Exchange (ETDEWEB)

The impacts of the expected climate change on Finnish lake ecosystems were studied with the biota of the mesohumic Lake Paeaejaervi, southern Finland. Experimental conditions, from small-scale experiments on single species level to a large-scale ecosystem manipulation, were established to simulate directly the future climate and/or loading of nutrients and dissolved organic matter (DOM) from the drainage area. The experimental studies were accomplished by modelling the carbon flow in the pelagic food web as well as the growth of littoral macrophytes. The main hypothese tested were as follows: As a consequence of the climate change (rising temperature and increasing precipitation) the loading of nutrients and dissolved organic matter (DOM) from the drainage area to the lake will increase. In the pelagic zone this will be first reflected i higher productivity of primary producers and bacteria, but will later affect the entire food chain. Increase in atmospheric ...

1996-12-31

458

Environmental data for sites in the National Solar Data Network  

Energy Technology Data Exchange (ETDEWEB)

The environmental data for the NSDN are presented in the form of tables for each solar site. The solar sites are grouped into 12 zones, each of which consists of several adjacent states. The solar energy sites are in alphabetical sequence within each zone. The tables provide available meteorological data for reporting sites in the NSDN as follows: Insolation - the insolation table presents the total, diffuse, direct, maximum, and extra-terrestrial radiation for the solar site. It also shows the ratio of total extra-terrestrial radiation, as a percent. Temperature - the temperature table gives the average, daytime, nightime, maximum, minimum and inlet-water temperatures for the solar site. Additional tables are presented for some of these NSDN sites, supplying either wind or relative humidity data, or both. Wind - all of the passive and some of the active solar sites are equipped with wind sensors. These provide information for two wind tables. ...

1980-12-01

459

Devonian-Mississippian oil shale resources of Kentucky: a summary  

Energy Technology Data Exchange (ETDEWEB)

Assessment of the oil shale resources in Kentucky has continued with 75 NX cores available where the oil shale crops out or is overlain by relatively thin cover in the area from Estill County westward to Bullitt County. In this 14 county area, the total black shale section thins across the crest of the Cincinnati arch and changes stratigraphically from that characteristic of the Ohio Shale in Estill County to that of the New Albany Shale in Bullitt County. Despite this stratigraphic transition the two high-carbon zones (greater than 8.0% carbon) can be traced across the arch. As the traverse is followed from the east, the intervening low-carbon zones thin such that at the crest of the arch, there are areas where the entire section of black shale contains more than 8% carbon. Then upon leaving the crest the two high-carbon zones separate again with one remaining at the very top of the section and one in the lower part. In ...

1985-02-01

460

Corrosion of container materials for disposal of high-level radioactive wastes  

Energy Technology Data Exchange (ETDEWEB)

In the corrosion aspect of container for the deep geological disposal of high-level radioactive waste, disposal concepts and the related container materials, which have been developed by advanced countries, have been reviewed. The disposal circumstances could be divided into the saturated and the unsaturated zones. The candidate materials in the countries, which consider the disposal in the unsaturated zone, are the corrosion resistant materials such as supper alloys and stainless steels, but those in the saturated zone is cupper, one of the corrosion allowable materials. By the results of the pitting corrosion test of sensitized stainless steels (such as 304, 304L, 316 and 316L), pitting potential is decreased with the degree of sensitization and the pitting corrosion resistance of 316L is higher than others. And so, the long-term corrosion experiment with 316L stainless steel specimens, sebsitized and non-sensitized, ...

1999-01-01

461

Comparison of wave energy flux for northern, central, and southern coast of California based on long-term statistical wave data  

Energy Technology Data Exchange (ETDEWEB)

California's pacific coast stretches roughly over 11.5 latitudinal degrees, extending from about 32.5{sup o}N to 44{sup o}N. There is nearly 900nm of California coastline offering superior opportunity for wave energy use. The longitudinal position of the coast shifts eastward at two distinct locations: Punta Gorda just south of Cape Mendecino in the north and Point Conception in the south. The change in longitudinal orientation in southern California also coincides with significant change in California's bathymetry. The tilts in the longitudinal coastal lines at the two points also define California wave zones into three areas: the short coastal line north of Punta Gorda, the long north and middle line between the two points, and the short line of the heavily populated southern coast. The northern and central zones are characterized by high waves of relatively low frequency; the southern coast is characterized by low waves of ...

2006-09-15

462

Comparison of in vitro disc diffusion and time kill-kinetic assays for the evaluation of antimicrobial wound dressing efficacy.  

Science.gov (United States)

There is a plethora of new silver-containing dressings on the market today. Various manufacturers attempt to show that their dressings are the most efficacious and therefore should be preferentially employed by health care workers based on the results of their in vitro tests. However, there have been no studies that clearly identify which tests are appropriate for comparison purposes. The purpose of this study was to determine which in vitro test is most appropriate for evaluating the antimicrobial efficacy of silver-containing dressings. This was done by testing seven silver-containing dressings and two non-silver-containing topical agents against 17 clinically relevant microorganisms using zone of inhibition assays and time-kill kinetic assays in complex media. The results for the two assays were then correlated to determine whether the methods generated similar results. It was determined that the two methods do not correlate at all. This is most likely a result ...

463

Chemical and biological monitoring of MIOR on the pilot area of Vyngapour oil field, West Sibera, Russia  

Energy Technology Data Exchange (ETDEWEB)

The pilot area of the Vyngapour oil field allotted for MIOR tests contains three injection and three producing wells. These wells were treated in summer 1993 and 1994. Before, during, and after MIOR treatments on the pilot area the chemical compounds of injected and formation waters were studied, as well as the amount and species of microorganisms entering the stratum with the injected water and indigenous bacteria presented in bottomhole zones of the wells. The results of monitoring showed that the bottomhole zone of the injection well already had biocenosis of heterotrophic, hydrocarbon-oxidizing, methanogenic, and sulfate-reducing bacteria, which were besides permanently introduced into the reservoir during the usual waterflooding. The nutritious composition activated vital functions of all bacterial species presented in the bottomhole zone of the injection well. The formation waters from producing wells showed the ...

1995-12-31

464

Biogeochemical cycling of N in tropical coastal zones: molecular microbial ecology of trace gas production.  

Environmental Research Database

ObjectivesThe specific objectives of the research are to: 1. Determine the concentrations of N2O, NO and NO2 in tropical coastal waters in relation to nutrients and salinities. 2. Determine, with excess nitrate present, the potential for nitrate reduction and denitrification in sediments along tropical estuaries, and whether NO, NO2, N2O, N2 or NH4+ are significant products. 3. Establish the balance between denitrification, nitrate ammonification and anammox in tropical estuarine sediments, relative to [continued...]DescriptionThe coastal zone is extremely important in the biogeochemical processes which control the natural cycle of elements of the Earth. In particular, the coastal zone contributes significantly to the nitrogen cycle, removing nitrogen washed in from the land by rivers and so reducing its fertilizing impact on the coastal seas. However, these removal processes, driven by microorganisms, also contribute to the formation of ...

2009-01-31

465

55 Cancri: Stellar Astrophysical Parameters, a Planet in the Habitable Zone, and Implications for the Radius of a Transiting Super-Earth  

CERN Document Server

The bright star 55 Cancri is known to host five planets, including a transiting super-Earth. The interferometric study presented here yields directly determined values for 55 Cnc's stellar astrophyiscal parameters: $R=0.943 \\pm 0.010 R_{\\odot}$, $T_{\\rm EFF} = 5196 \\pm 24$ K. We use isochrone fitting to determine 55 Cnc's age to be 10.2 $\\pm$ 2.5 Gyr, implying a stellar mass of $0.905 \\pm 0.015 M_{\\odot}$. Our analysis of the location and extent of the system's habitable zone (0.67--1.32 AU) shows that planet f ($M \\sin i = 0.155 M_{Jupiter}$) spends the majority of the duration of its elliptical orbit in the circumstellar habitable zone, where, with moderate greenhouse heating, it could harbor liquid water. Finally, our direct value for 55 Cancri's stellar radius allows for a model-independent calculation of the physical diameter of the transiting super-Earth 55 Cnc e ($\\sim 2.05 \\pm 0.15 R_{\\earth}$), which, depending on the ...

2011-01-01

466

Geologic and geomorphologic controls of the kaolin deposits of Campo Alegre basin (SC-Brazil); Controles geologicos e geomorfologicos dos depositos de caulim da Bacia de Campo Alegre, SC  

Energy Technology Data Exchange (ETDEWEB)

The most important kaolin deposits from Campo Alegre region (S C) were formed by the conjunction of at least one hydrothermal phase followed by many others weathering, supergenic, phases. Possibly deposits formed by only one of these processes exist, but these deposits shall be small and smaller than those mined today. Besides kaolinization, illitization/muscovitization and silicification, hydrothermalism also generated pyritized and propilitized zones, with quartz + chlorite. Together, hipogenic alterations related to kaolin deposits are very similar to alterations of high sulfidation epigenetic volcanogenic gold deposits. Most part of the biggest kaolin mines from the southern part of Campo Alegre Basin are distributed along a 13 Km long and 0,5 Km width bent zone that is parallel to structural alignments that point out the eastern Basin border. This zone was originated by deformation that has inclined and broken rocks, ...

2001-03-01

467

Types of nonanticlinal oil and gas traps and their dispersal within the island section of North Sakhalin  

Energy Technology Data Exchange (ETDEWEB)

Questions are examined of prospecting for nonanticlinical traps within North Sakhalin, their spatial distribution and evaluation of the outlook for oil and gas content. Traps of tapering and facial substitution on wings and periclines of local elevations, accumulative bar and erosion-accumulative channel are isolated. THe hypothesis is made that it is possible to form stratigraphic traps above the discrepancy and below it. It is noted that formation of zones of lithological tapering and facial substitution are associated with areas of the exchange of the sedimentation situation. The primary role of the shore and coastal zones in the formation of the examined types of nonanticlinal traps is established. The Okhino-Ekhabinskiy region in North Sakhalin is isolated as the primary object for prospecting for nonanticlinal traps.

1981-01-01

468

The significance of local hard zones on the outside of pipeline girth welds: Further studies  

Energy Technology Data Exchange (ETDEWEB)

The NACE MR-01-75 standard imposes a restriction of 22HRC maximum for regions of a pipeline girth weld that are not in direct contact with H[sub 2]S containing environments. TWI have demonstrated in an earlier project for the Pipeline Research Committee (PRC) that it may be permissible to relax this maximum hardness requirement. Such a relaxation, which already exists in the BS4515: 1984 standard, offers potential benefits when applied to the capping pass and heat affected zone of a pipeline girth weld. This report presents additional data to supplement that obtained in a previous PRC project conducted at TWI. Further pipe materials with differing pipe wall thicknesses have been welded, exposed to an internal H[sub 2]S containing environment and examined for sulphide stress corrosion cracking.

1991-10-01

469

The history of the coastal zones of the Great Caribbean tell through their sediments; La historia de las zonas costeras del Gran Caribe contada a traves de sus sedimentos  

Energy Technology Data Exchange (ETDEWEB)

The pollution of the aquatic zones grows with the time, principally due to industrial and urban settlements, among others, in the surroundings of these sites. The sources of this pollution can be identified by the study of the characteristics of the sediment, this gives relevant information to evaluate any aquatic system. Once the sediment is obtained, a series of preliminary tests are carry out (loss of ignition, 210{sup P}b dating) to be sure that we have a sedimentary core that hans .t be mixed, once this has be done we determine radionuclides, heavy metals and organic compounds. (Author) 2 refs.

2008-07-01

470

Study of seasonwise variations in the environmental gamma dose rates in Tarapur emergency planning zone (EPZ)  

International Nuclear Information System (INIS)

During the normal operation of a Nuclear Power Plant (NPP), radioactive releases into the atmosphere will be in small quantities. During major accidental situations, though the probability is extremely small, there may be significant release of radioactivity to the environment through the stack or at ground level. To study the external radiation exposure, if any, to the members of public due to releases during the normal operation of a nuclear power plant (NPP) and also to meet the requirement of emergency preparedness for the NPP site, continuous recording and analysis of environmental dose rate data is essential. This paper presents analysis of the gamma dose rates recorded by the Environmental Dose Logging Systems (EDLS) installed around the site during the last six years in the Emergency Planning Zone (EPZ) of Tarapur Atomic Power Station (TAPS). (author)

2005-11-23

471

Study of coastal water zone ecosystem health in Zhejiang Province based on remote sensing data and GIS  

British Library Electronic Table of Contents (United Kingdom)

The coastal ecosystem health assessment is a field of increasing importance. In this paper, a preliminary assessment of ecosystem health in Zhejiang coastal water zone was made, mainly based on remote sensing data and GIS technique. Its spatial and quantitative evaluation was facilitated by the progress of remote sensing and GIS technique development. Firstly, human activities, hydrology and ecosystem problems in the study area were discussed and analyzed. Secondly, from 4 aspects of human stress, physical, chemical and biological responses to anthropogenic activities and natural stress, several indicators such as water transparency (Secchi Disk Depth, SDD), suspended substance concentration, dissolved inorganic nitrogen, active phosphate, chlorophyll, harmful algae bloom, as well as distr...

2010-01-01

472

Simplified analytical model to simulate radionuclide release from radioactive waste trenches  

International Nuclear Information System (INIS)

In order to evaluate postclosure off-site doses from low-level radioactive waste disposal facilities, a computer code was developed to simulate the radionuclide released from waste form, transport through vadose zone and transport in the saturated zone. This paper describes the methodology used to model these process. The radionuclide released from the waste is calculated using a model based on first order kinetics and the transport through porous media was determined using semi-analytical solution of the mass transport equation, considering the limiting case of unidirectional convective transport with three-dimensional dispersion in an isotropic medium. The results obtained in this work were compared with other codes, showing good agreement. (author)

2010-11-24

473

Shallow groundwater nitrogen and denitrification in a newly afforested, subirrigated riparian buffer  

British Library Electronic Table of Contents (United Kingdom)

Summary 1. The EU -Nitrates Directive- (Directive 91/676/EEC) and the WFD (Water Framework Directive 2000/60/EEC) introduced a series of measures designed to reduce and prevent water pollution caused or induced by nitrates from agricultural sources. Therefore, there is an urgent requirement to control the nitrate concentration in freshwater. The objective of this paper was to verify the potential capacity of a specifically designed afforested riparian zone in removing the excess of nitrogen from river water. 2. A buffer zone was set with irrigation ditches, to produce a subsurface water flow carrying water from the study river through the buffer strip to drainage ditches. This experimental system enables the co-occurrence of two main processes: vegetation/microbial nitrogen uptake and deni...

2011-01-01

474

On plasma nitriding of steels  

Energy Technology Data Exchange (ETDEWEB)

With the aim of optimizing the nitriding process, experimental studies of the plasma nitriding of four selected steels were carried out, using a d.c. glow discharge. The process parameters were varied systematically. By means of transmission and scanning electron microscopy and X-ray diffraction, the microstructures, including the thicknesses of the compound zones and the diffusion zones of the nitrided steels, were obtained. Using cross-sectional samples and a micro-Vickers indenter, hardness depth profiles were also obtained. From the time and temperature dependences of the hardness profiles, effective diffusion constants and corresponding activation enthalpies were obtained. Furthermore, in an attempt to shed some light on the atomistic nitriding mechanisms, the glow discharges were studied by measuring energy spectra of the energetic ions hitting the cathode (the steel test specimens). It was shown that an increase of the mean energy of the ...

2000-02-01

475

Microstructure of c-BN films deposited by IBAD: IR and HREM analyses  

International Nuclear Information System (INIS)

The in-depth distribution of phases in c-BN films deposited by Ion Beam Assisted Deposition (IBAD) at two different ion energy values (300 and 600 eV) was investigated using the quantitative IR transmission measurements and the HREM technique. Whatever the value of the studied ion energies, the characteristic layered morphology of c-BN film is observed including the interfacial sp"2 zone between the substrate and the c-BN volume. In the case of 600 eV ion energy, this interfacial zone is less well-defined in comparison with 300 eV ion energy and the corresponding thickness is more important. Furthermore, the h-BN phase is more diluted within the c-BN film volume showing that the purest phase concentration of c-BN is found for the lowest ion energy, i.e., 300 eV.

1997-04-04

476

Investigation into some tribological properties of plasma nitrided hot-worked tool steel AISI H11  

Energy Technology Data Exchange (ETDEWEB)

Interest in the tribological properties of plasma nitriding has increased substantially over the past years because plasma nitriding provides a high nitride depth and improved hard facing. The present study examines the tribological properties of AISI H11 plasma nitrided, hot-worked steel. Different nitriding temperatures and durations were considered. Characterization of the composite structures was investigated with wear tests, x-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and microhardness tests. The depth profile of the nitrided zone was measured using the nuclear reaction analysis (NRA) technique. Plasma nitriding affected the microhardness, wear properties, and morphology considerably. Increase in process temperature increased the nitride zone depth.

1996-04-01

477

Implementation and modification of a three-dimensional radiation stress formulation for surf zone and rip-current applications  

British Library Electronic Table of Contents (United Kingdom)

Regional Ocean Modeling System (ROMS v 3.0), a three-dimensional numerical ocean model, was previously enhanced for shallow water applications by including wave-induced radiation stress forcing provided through coupling to wave propagation models (SWAN, REF/DIF). This enhancement made it suitable for surf zone applications as demonstrated using examples of obliquely incident waves on a planar beach and rip current formation in longshore bar trough morphology (Haas and Warner, 2009). In this contribution, we present an update to the coupled model which implements a wave roller model and also a modified method of the radiation stress term based on Mellor (2008, 2011a,b,in press) that includes a vertical distribution which better simulates non-conservative (i.e., wave breaking) processes and ...

2011-01-01

478

Frequency distribution, isotopic composition and physical characterization of plutonium-bearing particles from the Fig-Quince zone on Runit Island, Enewetak Atoll  

British Library Electronic Table of Contents (United Kingdom)

Runit Island on Enewetak Atoll was very heavily impacted by the U.S. nuclear testing campaign in the northern Marshall Islands (1946?58). The primary source of contamination on Runit Island was the 1958 Quince safety test where a large quantity of device plutonium (Pu) was scattered over the area near the GZ. A second low-yield device was detonated on the same site 10?days later, further disturbing the soil and leaving behind a very heterogeneous pattern of contamination including milligram-size particles of plutonium. A limited cleanup of the Fig-Quince zone was carried out in 1979. During this period, the effectiveness of the cleanup operations was primarily evaluated on the basis of bulk soil concentration data with little consideration given to the heterogeneity and long-term material-...

2009-01-01

479

Feeding ecology of mesopelagic zooplankton of the subtropical and subarctic North Pacific Ocean determined with fatty acid biomarkers  

British Library Electronic Table of Contents (United Kingdom)

Mesopelagic zooplankton may meet their nutritional and metabolic requirements in a number of ways including consumption of sinking particles, carnivory, and vertical migration. How these feeding modes change with depth or location, however, is poorly known. We analyzed fatty acid (FA) profiles to characterize zooplankton diet and large particle (>51?m) composition in the mesopelagic zone (base of euphotic zone ?1000m) at two contrasting time-series sites in the subarctic (station K2) and subtropical (station ALOHA) Pacific Ocean. Total FA concentration was 15.5 times higher in zooplankton tissue at K2, largely due to FA storage by seasonal vertical migrators such as Neocalanus and Eucalanus. FA biomarkers specific to herbivory implied a higher plant-derived food sou...

2010-01-01

480

Environmental impact of a nuclear plant on Mississippi River biota in an ecological recovery zone near Red Wing, Minnesota. Final report  

International Nuclear Information System (INIS)

The biota of the Mississippi River in an ecological recovery zone near Red Wing, MN was studied before and after start-up of a nuclear plant to acquire baseline data and to estimate changes due to thermal addition. Thermal addition produced significant decreases in primary production in a plant region during summer month periods when water temperatures were near 36C. Extensive fisheries studies and sonar tagging/tracking of S. vitreum were performed. Comparison of fisheries results with other riverine, lake, and pond studies indicated a favorable environment for the success of the fish species studied. Qualitative macroinvertebrate surveys were conducted.

481

Electrical properties of focused-ion-beam boron-implanted silicon  

International Nuclear Information System (INIS)

Electrical properties of 16 keV, focused-ion-beam (FIB) (beam diameter: 1 #mu#m, current density: 50 mA/cm"2) boron-implanted silicon layers have been investigated as a function of beam scan speed and ion dose, and compared with those obtained by conventional implantation (current density: 0.4 #mu#A/cm"2). High electrical activation of the FIB implanted layers is obtained by annealing below 800"0C as a result of the increase in amorphous zones created in the implanted layers. Amorphous zone overlapping is assumed to occur at FIB implantation doses of 3 - 4 x 10"1"5 ions/cm"2 from the results of electrical activation and the carrier profile of implanted regions annealed at low temperature, if beam scan speed is lowered to about 10"-"2 cm/s. (author).

482

Continuous method development and numerical study of HHV water gas production by pulverized coal  

British Library Electronic Table of Contents (United Kingdom)

In energy industries, it is always of difficulty to produce high heat value(HHV) gas continuously using pulverized coal. In this paper, a new type furnace for partitioned alternative gasification using pulverized coal is developed, in which the oxidation and reduction reaction occur alternatively with the dropping of pulverized coal and finally HHV gas could be continuously obtained at the reduction zone exit and low heat value(LHV) gas at the oxidation zone exit. Furthermore, the gasification characteristics and their factors in furnace are numerically simulated under two dimensional model with a self-coded program, based on heat, mass and energy transfer as well as reaction principles. It is found that the producing rate of HHV gas is 1.10Nm3/kg with heat value of 11.72MJ/Nm3, however, t...

2011-01-01

483

Bumper zone at the Aldermac mine tailing site : study of certain remediation techniques; Zones d'epanchement du parc a residus miniers Aldermac : etude de certaines techniques de rehabilitation  

Energy Technology Data Exchange (ETDEWEB)

Acid mine drainage is probably the most important problem facing the mining industry. In this study, the authors evaluated different techniques for the remediation of mine tailings. An in situ characterization of the Aldermac mine tailings was conducted and the results were presented in this poster presentation. The site characterization was performed to determine the extent of the contamination, and sampling of soils was also performed for laboratory experiments in soil covers. The authors described the methodology followed in the laboratory experiments. Chemical analysis of the leaching water was performed to determine its composition in metals. Microbiological analysis was also conducted, as well as the determination of the water saturation index. The authors indicated that they will analyze the results further. tabs., 12 figs.

2000-07-01

484

Bubble nucleation, growth and coalescence during the 1997 Vulcanian explosions of Soufriere Hills Volcano, Montserrat  

British Library Electronic Table of Contents (United Kingdom)

Soufriere Hills Volcano had two periods of repetitive Vulcanian activity in 1997. Each explosion discharged the contents of the upper 0.5-2km of the conduit as pyroclastic flows and fallout: frothy pumices from a deep, gas-rich zone, lava and breadcrust bombs from a degassed lava plug, and dense pumices from a transition zone. Vesicles constitute 1-66vol.% of breadcrust bombs and 24-79% of pumices, all those larger than a few tens of m being interconnected. Small vesicles (few hundreds of m) in pumices are interpreted as pre-dating explosion, implying pre-explosive conduit porosities up to 55%. About a sixth of large vesicles in pumices, and all those in breadcrust bombs, are angular voids formed by syn-explosive fracturing of amphibole phenocrysts. An intermediate-sized vesicle population...

2010-01-01

485

Behaviour of different artificial weak zones in superconducting elements working in inductive fault current limiters  

International Nuclear Information System (INIS)

The thermal recovery of superconducting elements working as secondaries in fault current limiters can be enhanced by taking advantage of the removal of heat by conduction from an array of artificial weak zones (AWZ) distributed along the superconductor perimeter (hot parts) to the non-weak segments (cold parts). These results were obtained by studying samples with weak parts in the shape of grooves, all identical in size. In this paper we consider the case in which one of the AWZ is slightly different from the rest. Our results show that a change in its length has a negligible effect. On the contrary, a groove which is slightly deeper can be overheated and hence can strongly determine the recovery time of the whole limiter.

2010-06-01

486

Application of the CFAST zone model to the Fire PSA  

British Library Electronic Table of Contents (United Kingdom)

The integrity of the cables located in the target room is very important in the Fire PSA, because the CDF and CCDP are changed according to the results of a cable integrity that depends on the surrounding gas temperature. The conservative assumptions used in the Fire PSA typically specify that all of the equipment and cables of a room would fail when a fire happens in the room. But the realistic assessment of a fire risk by using a fire simulation tool has become necessary in the Fire PSA as described in the ANS Fire PRA Standard. This paper evaluates the cable integrity of eight pump rooms in the nuclear power plant by using the CFAST zone fire model. The upper layer gas temperature of each room is estimated, and an analysis based on the results of model simulations is used to judge the c...

2010-01-01

487

An examination of the exhaust emissions of gas fueled diesel engines  

Energy Technology Data Exchange (ETDEWEB)

A multi-zone computational model in conjunction with some engine tests are used to examine the combustion process of gas fueled diesel engines common known as dual fuel engine to provide information about details of the production of exhaust emissions, especially at light load when very lean mixtures are employed. Detailed chemical reaction kinetic simulation is employed for each of these individual combustion zones so as to establish the associated temporal variations in the concentrations of reacting species right to the exhaust stage. The influence of changes in major operating and design parameters such as the concentration of the gaseous fuel in the cylinder charge, intake temperature and the size of the diesel pilot fuel employed on the production of the exhaust emissions are examined. It is demonstrated in general that any measure that tends to increase the size of the combustion regions within the overly lean cylinder charge will reduce ...

1996-12-31

488

An examination of the exhaust emissions of gas fueled diesel engines  

Energy Technology Data Exchange (ETDEWEB)

A multi-zone computational model in conjunction with some engine tests are used to examine the combustion process of gas fueled diesel engines commonly known as dual fuel engine to provide information about details of the production of exhaust emissions, especially at light load when very lean mixtures are employed. Detailed chemical reaction kinetic simulation is employed for each of these individual combustion zones so as to establish the associated temporal variations in the concentrations of reacting species right to the exhaust stage. The influence of changes in major operating and design parameters such as the concentration of the gaseous fuel in the cylinder charge, intake temperature and the size of the diesel pilot fuel employed on the production of the exhaust emissions are examined. It is demonstrated in general that any measure that tends to increase the size of the combustion regions within the overly lean cylinder charge will ...

1997-07-01

489

Adaptive smearing for Brillouin zone integration  

British Library Electronic Table of Contents (United Kingdom)

Abstract We suggest a simple scheme for automatically determining the width parameter of smearing methods of the Brillouin zone integration in electronic structure calculation. The scheme retains one free parameter that at any time can be eliminated by choosing a denser k-space mesh until the desired accuracy is obtained. The tests are carried out in the context of Methfessel-Paxton smearing. This adaptive Gaussian smearing (AGS) is easily implemented, variational with respect to partial occupancies and free from spurious occupancies that are negative or larger than one. Its convergence properties are similar to those obtained with the modified tetrahedron method for energy resolution of -0.1 meV. 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011

2011-01-01

490

Accumulation of glycosaminoglycans in radiation-induced muscular fibrosis  

Energy Technology Data Exchange (ETDEWEB)

The content and biosynthesis of glycosaminoglycans (GAGs) were studied in pig thigh muscle after acute local {gamma}-irradiation. Seven months following irradiation, the muscular tissue next to the irradiation cone was replaced by severe mutilating fibrosis delimited by an intermediary perifibrotic zone. Results showed a parallel increase of collagen and GAG content in perifibrotic and fibrotic tissues. Sulphated GAGs, heparan sulphate and dermatan sulphate were preferentially accumulated in fibrotic tissue, while the hyaluronic acid content increased only slightly. Synthesis of sulphated GAGs was more elevated in fibrotic tissue than in perifibrotic zone as compared with normal muscle. Seven months after irradiation well-developed fibrotic tissue continued to synthesize and to accumulate extracellular matrix macromolecules. (Author).

1992-05-01

491

A shallow subsurface controlled release facility in Bozeman, Montana, USA, for testing near surface CO2 detection techniques and transport models  

Energy Technology Data Exchange (ETDEWEB)

A controlled field pilot has been developed in Bozeman, Montana, USA, to study near surface CO2 transport and detection technologies. A slotted horizontal well divided into six zones was installed in the shallow subsurface. The scale and CO2 release rates were chosen to be relevant to developing monitoring strategies for geological carbon storage. The field site was characterized before injection, and CO2 transport and concentrations in saturated soil and the vadose zone were modeled. Controlled releases of CO2 from the horizontal well were performed in the summers of 2007 and 2008, and collaborators from six national labs, three universities, and the U.S. Geological Survey investigated movement of CO2 through the soil, water, plants, and air with a wide range of near surface detection techniques. An overview of these results will be presented.

2009-10-20

492

A new approach to fabrication of gradient WC-Co hardmetals  

British Library Electronic Table of Contents (United Kingdom)

WC-Co hardmetals with gradient structure comprising neither -phase nor grain growth inhibitors were produced for the first time by regulating the WC re-crystallisation and carbon content in their near-surface layer and core. Hardmetals with low Co contents in the surface region were obtained by selective carburisation of the near-surface zone of green articles with the original low carbon content and their consequent liquid-phase sintering. The surface region of such gradient hardmetals has a hardness of up 150 Vickers units higher and fracture toughness significantly superior than those of the core. Gradient hardmetals with high Co contents in the surface region were obtained by selective decarburisation of the near-surface zone of green articles with the original high carbon content and ...

2010-01-01

493

3-D prestack migration in anisotropic media  

Energy Technology Data Exchange (ETDEWEB)

A three-dimensional (3-D) prestack reverse-time migration algorithm for common-source P-wave data from anisotropic media is developed and illustrated by application to synthetic data. Both extrapolation of the data and computation of the excitation-time imaging condition are implemented using a second-order finite-difference solution of the 3-D anisotropic scalar-wave equation. Poorly focused, distorted images are obtained if data from anisotropic media are migrated using isotropic extrapolation; well focused, clear images are obtained using anisotropic extrapolation. A priori estimation of the 3-D anisotropic velocity distribution is required. Zones of anomalous, directionally dependent reflectivity associated with anisotropic fracture zones are detectable in both the 3-D common-source data and the corresponding migrated images.

1993-01-01

494

Impurity and clustering effects on defect evolution in ion-implanted Si  

Energy Technology Data Exchange (ETDEWEB)

A detailed investigation of the damage formation and evolution in ion-implanted crystalline Si is presented. Deep-level transient spectroscopy has been used to monitor room temperature migration of point defect complexes and evolution from simple point-like defect complexes to defect clusters and even extended defects. Si samples were implanted with Si or He ions with energies of 145 keV-3MeV, to fluences in the range 5x10[sup 8]-5x10[sup 13]cm[sup -2]. The effects of thermal annealing, in the range 100-680 C and 10 min-15h, were also explored. A systematic comparison of defect complexes formation and evolution in ion-implanted or electron-irradiated Si samples with a different impurity content were used to assess the role of impurities (C and O), extra implanted ion and defect clustering on the nature and thermal stability of residual damage. In particular, an interstitial excess directly resulting from the extra implanted ...

1998-10-01

495

Frontiers of Nuclear Astrophysics  

International Nuclear Information System (INIS)

The main goals of nuclear astrophysics have been to probe the interiors of stars, stellar explosions, the early moments of cosmic expansion, and the formation and evolution of galaxies and cosmic structure by measurement and application of the relevant nuclear physics. The approach to these goals have generally been from three directions: 1) Careful measurements of the relevant nuclear reactions; 2) Detailed computer models of the relevant astrophysical environments; and 3) Observations of the relevant terrestrial and extra-terrestrial atomic and isotopic abundances. These approaches provide not only insight into the formation and evolution of the elements, but are also pillars upon which a variety of cosmological models as well as models for physics beyond the standard model of particle physics can stand or fall. At present there is a very exciting frontier on all three of these approaches. The development and applications of ...

2008-06-01

496

Identification of source and recharge zones in an aquifer system from water stable isotope. Case Study Bajo Cauca Antioqueno  

International Nuclear Information System (INIS)

Hydrology and hydrogeochemical are auxiliary techniques to valid conceptual hydrogeology an recharge models. Stable isotopes from water trace sources and path flow and Tritium indicates age. This paper is about the use of D 18, D2H y 3H to study the aquifer system on Bajo Cauca antioqueno.

497

Aerosol influenza transmission risk contours: A study of humid tropics versus winter temperate zone  

UK PubMed Central (United Kingdom)

BackgroundIn recent years, much attention has been given to the spread of influenza around the world. With the continuing human outbreak of H5N1 beginning in 2003 and the H1N1 pandemic...Full Text Available