The collision of the Earth with extra-terrestrial ice-volatile bodies is proposed as a mechanism to produce rapid changes in the geologic record. These bodies would be analogs of the ice satellites found for the Jovian planets and suspected for comets and certain low density bodies in the Asteroid belt. Five generic end-members are postulated: (1) water ice; (2) dry ice: carbon-carbon dioxide rich, (3) oceanic (chloride) ice; (4) sulfur-rich ice; (5) ammonia hydrate-rich ice; and (6) clathrate: methane-rich ice. Due to the volatile nature of these bodies, evidence for their impact with the Earth would be subtle and probably best reflected geochemically or in the fossil record. Actual boloids impacting the Earth may have a variable composition, generally some admixture with water ...
Some considerations regarding ice load in risk-based dam safety analysis are presented for small concrete dams. The most significant physical mechanisms leading to ice thrust on dams (such as thermal expansion and water level fluctuations) are outlined. Published literature on dam ice loads to examine ice load magnitude-return period relationships, sliding and overstressing failure mechanisms and structural performance criteria to resist ice loads, are also reviewed. Related loading combinations for structural safety evaluations were determined regarding the issue of simultaneity of ice loads with other events such as earthquakes. Parametric analyses were conducted on a small gravity dam section, 3m high, and a taller dam, 17.9 m high, to demonstrate the ultimate ice load carrying capability as a function of dam geometry ...
Positive identification of Martian pseudocraters would be a strong indication of past occurrence of ice at or near the surface of Mars. The basis for suggesting that small cones on Mars are pseudocraters includes: (1) small size, (2) abundant but patchy distribution on what appear to be volcanic plains, (3) presence of other features suggestive of surface or subsurface ice, (4) morphological similarities to Icelandic pseudocraters, and (5) the similarity in distribution of crater/cone diameter ratios to Icelandic pseudocraters. This last morphometric parameter may be the most important, since other possible small terrestrial volcanic analogs have very different crater/cone diameter ratio distributions. In a survey of the available high resolution Viking Orbiter imagery, abundant fields of possible pseudocraters were found. However, only a small fraction of the plains forming units imaged at high resolution were found to ...
Part I of this thesis is on long-term iceberg collision-risk assessment methods for fixed offshore structures. Estimates for the long-term probability that an iceberg will hit a fixed offshore structure are based on estimates of the total volume of produced iceberg, a model for the size distribution of icebergs and a description of how iceberg trajectories ``fill`` the plane (the ocean`s surface). Part II of the thesis discusses methods for analysis of low resolution data in the sense that the size of the area covered by each pixel is not small compared to the dominating floes. Still, this type of data can provide estimates of the ice extent (and hence the ice edge) and ice concentration. The estimates of the ice edge (at least) seem to be physically significant in the sense that ``in some way`` they can reflect ice drift in an image time sequence. A priori this ...
BackgroundMany commercial banana varieties lack sources of resistance to pests and diseases, as a consequence of sterility and narrow genetic background. Fertile wild relatives,...Full Text Available
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...
A three-dimensional numerical simulation of mammatus-like clouds is presented. A portion of a cirrus outflow anvil cloud is simulated including cloud ice and snow microphysical representations. The simulated mammatus clouds appear in a cellular pattern and are compared with the few available previously published physical observations of mammatus. Copyright Copyright 2006 Royal Meteorological Society
Manitoba Hydro's Ice Storm Management Program to reduce ice damage to overhead power lines in the voltage range of 8 kV to 115 kV is described. Overhead power lines are de-iced either by AC ice melting, which involves placing a three-phase short at a calculated point, or ice rolling, which is a process of mechanically stripping ice from conductors. Direct current heating and underground distribution systems are also accepted prevention measures. Advantages and disadvantages of each of these methods of de-icing are reviewed. Material for this paper has been extracted from a workshop manual prepared for the 1993 and 1998 Ice Storm Management workshops organized by Manitoba Hydro through the Canadian Electrical Association. 1 ref.
The characteristics of solidification and melting are reviewed. The properties of water and ice and the phase diagram of water are discussed with special emphasis on ice density. A concise account of the freezing process and the Stefan problem is presented. To this end, the four stages of freezing are identified, supercooling, nucleation and the formation of dendritic ice, the growth of concentric rings of solid ice at 0{sup o}C and the final cooling of the solid ice are treated in some detail. The subject of bursting of pipes is given particular emphasis. Attention is drawn to a common misconception on pipe bursting and to misleading relationships for the computation of freezing time for ice blockage. Several current applications of melting and freezing systems are outlined. (author)
In cold countries, the design of transmission lines and communication networks requires the knowledge of ice loads on conductors. Atmospheric icing is a stochastic phenomenon and therefore probabilistic design is used more and more for structure icing analysis. For strength and reliability assessments, a data base on atmospheric icing is needed to characterize the distributions of ice load and corresponding meteorological parameters. A test site where icing is frequent is used to obtain field data on atmospheric icing. This test site is located on the Mt. Valin, near Chicoutimi, Quebec, Canada. The experimental installation is mainly composed of various instrumented but non-energized test cables, meteorological instruments, a data acquisition system, and a video recorder. Several types of icing events can produce large ...
The stability of a solid ice cover subjected to rapidly varying water levels and discharge was investigated. The support from the bank limits the stress in the ice cover and consequently bank contact must be maintained to ensure ice cover stability. An analysis was required of the stability of ice hinges, a flexible connection between a solid ice cover and the riverbank. Phase II and phase III of the research involved a field study of the Peace River, investigating the evolution of ice hinges with water level variation, from initial ice cover cracking parallel to the banks, to a fully developed hinge. A test program of midwinter discharge variations was undertaken to gather specific data and measurements of ice hinge link length, ice thickness, hinge joint behavior, riverbank geometry, and response ...
An overview of climatic factors and impact relative to river ice engineering and science is presented. An explanation of the fundamentals of climatic change is followed by a review of direct and indirect climatic influences that govern river ice breakup and related trends. Known responses of river ice to climatic change and potential future changes to ice breakup processes are described along with the probable ecological and socio-economic consequences of these changes. Changes in engineering approaches to accommodate the present ice regime and predicted changes in climatic variables that affect river ice processes and reduce the vulnerability of infrastructure and ecosystems to climatic change are examined. Future research on the links between river ice and stream ecology is suggested to identify ecological concerns that may result from ...
A model is presented which describes the formation of surface damage ``gouging`` on the rails that guide rocket sleds. An unbalanced sled can randomly cause a very shallow-angle, oblique impact between the sled shoe and the rail. This damage phenomenon has also been observed in high-velocity guns where the projectile is analogous to the moving sled shoe and the gun barrel is analogous to the stationary rail. At sufficiently high velocity, the oblique impact will produce a thin hot layer of soft material on the contact surfaces. Under the action of a normal moving load, the soft layer lends itself to an anti-symmetric deformation and the formation of a ``hump`` in front of the moving load. A gouge is formed when this hump is overrun by the sled shoe. The phenomenon is simulated numerically using the CTH strong shock physics code, and the results are in good agreement with experimental observation.
When backward time travel through wormholes is taken into account, classical physics loses its determinism and allows simulation of some quantum behaviours. We show how it is possible to simulate a non-local wavefunction reduction-type effect, i.e. we present a mechanical analogy for the collapse of the wavefunction of an entangled state of two removed particles. This situation can be seen as the simplest EPR situation, i.e. the situation where there is just one direction to measure along the spin (or the correlated properties). We present no rigorous results here, just a different point of view about something that is generally thought to be impossible: modelling a quantum indeterministic and non-local behaviour with a mechanical system.
Ice jamming, known to cause high water levels at even moderate river flows, is described as both the main and least understood source of ice-related bridge damages. This paper describes a joint study by the New Brunswick Department of Transportation, the Department of the Environment, local governments, and the National Water Research Institute, designed to address problems associated with the interaction of ice jams and bridges. The study consists of collecting information at each of four sites in New Brunswick including: historical data on ice jam locations, causes, and water levels; channel bathymetry, width and slope within each study centred at the respective bridge; and documentation of ice conditions throughout the ice season, including measurement of ice cover thickness, observation of breakup mechanisms, times, causes, ...
Glacier ice worms, Mesenchytraeus solifugus and related species, are the largest glacially obligate metazoans. As one component of cold temperature adaptation, ice worms maintain atypically...Full Text Available
DescriptionRates of ice accumulation in Antarctica are not known well, yet they are fundamental to assessing the ice sheet mass balance. Past accumulation rates are less well defined. We are in a unique position to provide detailed accounts of accumulation in Antarctica. We will measure isochronous internal layering across the ice sheet, which can be readily identified in radar data that we hold. Internal layers will be traced to ice-cores (allowing dating) and across wide regions of the ice sheets. A nume [continued...
Development of a strategy for forecasting river ice breakup and jamming on the Saint John River in New Brunswick was described. Methods used to identify ice jam-prone areas by simple temperature-based methods to fairly complex computer models using site specific data, were summarized. Recent technological advances in developing forecasts, including the NWRI probe for remotely measuring ice jam thickness, the RIVJAM model for determining stages upstream of an ice jam, and computational procedures for estimating the thrust exerted by ice jams against bridges, were also reviewed. Criteria and recommendations for river ice breakup and ice jamming for the Saint John River were provided. (Abstract only).
The stability of a solid ice cover subjected to rapidly varying water levels and discharge was investigated. The support from the bank limits the stress in the ice cover and consequently bank contact must be maintained to ensure ice cover stability. An analysis was required of the stability of ice hinges, a flexible connection between a solid ice cover and the riverbank. Phase II and phase III of the research involved a field study of the Peace River, investigating the evolution of ice hinges with water level variation, from initial ice cover cracking parallel to the banks, to a fully developed hinge. A test program of midwinter discharge variations was undertaken to gather specific data and measurements of ice hinge link length, ice thickness, hinge joint behavior, riverbank geometry, and response ...
Since the commissioning of the first 10 strings of the AMANDA neutrino telescope, more than nine years of data has been collected. The proof of principle of high-energy neutrino detection in ice is established. No positive signal of an extra-terrestrial high-energy neutrino flux have been found so far. However, the most stringent upper limits to the flux of cosmic neutrinos-respectively, diffuse, point like or associated with gamma-ray bursts-have been presented. A sample of 3329 up-going muon tracks, representing the largest statistics ever of high-energy neutrino induced events, has been collected between 2000 and 2003. A coincidence of neutrino with an anomalous high-energy gamma-ray flare has been observed from the direction of the Blazar 1ES1959+650-although the observation were not conclusive. Selected results of data taken with the AMANDA detector are here reported.
Substantial thermal performance improvement in ice-on-tube cold thermal energy storage systems (TES) is possible by making use of porous copper mesh as a Heat Conducting Enhancement Device (HCED). HCEDs are inexpensive heat transfer augmentation devices that can result in faster rate of ice growth and larger final steady state ice build volume by reducing the controlling thermal conduction resistance of the ice layer. This improves the competitiveness of external ice-on-tube systems as compared to other TES systems, such as dynamic ice harvesters and static internal melt systems. In this study the amount of ice growth enhancement is predicted theoretically, by performing simplified 1-D calculations, and is then validated in the laboratory through carefully controlled experiments. This study shows that ice volume increase ...
This report describes development of an electronic system designed to reduce vibration generated by a cryocooler. The diminished vibration makes it practical to use the active cooler to extract heat from a portable gamma ray detector instrument. The system was developed for a Sunpower cryocooler with an integrated counterbalance mass. The overall momentum cancellation approach is also applicable to other similar cryocoolers. The cancellation system is an assembly of several components tailored to accomplish the required vibration reduction with minimum power consumption and volume. It is designed to be powered by a 18--32 Volt battery. Up to ten harmonics of the 58.65 Hz drive frequency are controlled. In addition to the vibration cancellation, the electronic system produces the drive signal for the cryocooler and regulates the cooler temperature. The system employs a sinusoidal drive to reduce the amount of higher harmonic vibration. A digital signal processor (DSP) is used to perform ...
retrieve detailed aerosol and cloud particle size distribution and shape ...... but on rain types, and hydrometeor characteristics. ..... of ice streams, decreasing sea ice cover in the Arctic, poleward movement of forest cover, and ...
... small water or ice particles by impaction ... flight recording; principally the hydrometeor charge unit ... capability of directing aircraft movements by radio ...
Neutrino emission drives neutron star cooling for the first several hundreds of years after its birth. Given the low energy ($\\sim$ keV) nature of this process, one expects very few nonstandard particle physics contributions which could affect this rate. Requiring that any new physics contributions involve light degrees of freedom, one of the likely candidates which can affect the cooling process would be a nonzero magnetic moment for the neutrino. To illustrate, we compute the emission rate for neutrino pair bremsstrahlung in neutron-neutron scattering through photon-neutrino magnetic moment coupling. We also present analogous differential rates for neutrino scattering off nucleons and electrons that determine neutrino opacities in supernovae. Employing current upper bounds from collider experiments on the tau magnetic moment, we find that the neutrino emission rate can exceed the rate through neutral current electroweak ...
A single round of Edman degradation was employed to remove the NH_2-terminal valine from isolated #alpha# chains of human hemoglobin. Reconstitution of normal #beta# chains with truncated or substituted #alpha# chains was used to form truncated (des-Val"1-#alpha#1) and substituted ([[1-"1"3C]Gly"1]#alpha#1) tetrameric hemoglobin analogs. Structural homology of the analogs with untreated native hemoglobin was established by using several spectroscopic and physical methods. Functional studies indicate that the reconstituted tetrameric protein containing des-Val"1-#alpha# chains has a higher affinity for oxygen, is less influenced by chloride ions or 2,3-biphosphoglycerate, and shows lower cooperativity than native hemoglobin. These results confirm the key functional role of the #alpha#-chain NH_2 terminus in mediating cooperative oxygen binding across the dimer interface. The NH_2-terminal pK/sub 1/2/ value was determined for ...
We develop a continuum description for the axial segregation of granular materials in a long rotating drum based on the dynamics of the thin near-surface granular flow coupled to bulk flow. The equations of motion are reduced to the one-dimensional system for two local variables only, the concentration difference and the dynamic angle of repose, or the average slope of the free surface. The parameters of the system are established from comparison with experimental data. The resulting system describes both initial transient traveling wave dynamics and the formation of quasi-stationary bands of segregated materials. A long-term evolution proceeds through slow logarithmic coarsening of the band structure which is analogous to the spinoidal decomposition described by the Cahn-Hilliard equation. {copyright} {ital 1999} {ital The American Physical Society}
We develop a continuum description for the axial segregation of granular materials in a long rotating drum based on the dynamics of the thin near-surface granular flow coupled to bulk flow. The equations of motion are reduced to the one-dimensional system for two local variables only, the concentration difference and the dynamic angle of repose, or the average slope of the free surface. The parameters of the system are established from comparison with experimental data. The resulting system describes both initial transient traveling wave dynamics and the formation of quasi-stationary bands of segregated materials. A long-term evolution proceeds through slow logarithmic coarsening of the band structure which is analogous to the spinoidal decomposition described by the Cahn-Hilliard equation. copyright 1999 The American Physical Society
A distinct feature of Coulomb gauge QCD is that it can be formulated in terms of physical, transverse gluons and quarks alone. The state-counting is then transparent, and the gauge is suited for studies of the excited spectrum. Leaving aside exotic spectroscopy, which has been the subject of other publications, in this note I call attention on two recent applications. One is that the running quark mass in the mid-infrared can be probed from excited baryons thanks to parity doubling, a consequence of insensitivity to chiral symmetry breaking. Fast quarks are asymptotically free and behave as massless, so hadrons containing fast quarks decouple from the condensate. Their (power-law) rate of decoupling reflects on the rate of decreasing parity splittings, which can be measured. The second is that, in analogy with the Franck-Condon principle of molecular physics, the velocity distribution of the heavy quarks inside a heavy ...
This paper bundles 40 contributions by the IceCube collaboration that were submitted to the 30th International Cosmic Ray Conference ICRC 2007. The articles cover studies on cosmic rays and atmospheric neutrinos, searches for non-localized, extraterrestrial {nu}{sub e}, {nu}{sub {mu}} and {nu}{sub {tau}} signals, scans for steady and intermittent neutrino point sources, searches for dark matter candidates, magnetic monopoles and other exotic particles, improvements in analysis techniques, as well as future detector extensions. The IceCube observatory will be finalized in 2011 to form a cubic-kilometer ice-Cherenkov detector at the location of the geographic South Pole. At the present state of construction, IceCube consists of 52 paired IceTop surface tanks and 22 IceCube strings with a total of 1426 Digital Optical Modules deployed at depths up to 2350 m. The ...
After several years of planning and workshop meetings, a decision was reached in late 2008 to organize PICMG xTCA for Physics Technical Subcommittees to extend the ATCA and MTCA telecom standards for enhanced system performance, availability and interoperability for physics controls and applications hardware and software. Since formation in May-June 2009, the Hardware Technical Subcommittee has developed a number of ATCA, ARTM, AMC, MTCA and RTM extensions to be completed in mid-to-late 2010. The Software Technical Subcommittee is developing guidelines to promote interoperability of modules designed by industry and laboratories, in particular focusing on middleware and generic application interfaces such as Standard Process Model, Standard Device Model and Standard Hardware API. The paper describes the prototype design work completed by the lab-industry partners to date, the timeline for hardware releases to PICMG for approval, and the status ...
An analytical study of the ice-formation process associated with heat-conducting plates located perpendicularly to isothermally heated and cooled surfaces with some clearance is presented. It is proposed that the onset conditions, which describe whether the ice-volume fraction in a steady state is greater than or less than that without heat-conducting plates, are defined by the dimensionless distances between the heated/cooled walls and the heat-conducting plates. It is shown that the onset conditions are dependent on the pitch and the thickness of the heat-conducting plates and are less dependent on the thermal conductivity of the plates.
A near-real-time integrated temperature and water vapor sounding system has been designed and in operation since June 1993. It combines hourly data from the ground-based radio acoustic sounding system (RASS), a two-channel microwave radiometer, standard surface meteorological instruments, a lidar ceilometer, and the Aerodynamic Research Incorporated Communication, Addressing and Reporting System aboard commercial airlines with space-based data from the TIROS-N Operational Vertical Sounder (TOVS). The physical retrieval algorithm provided by the International TOVS Processing Package is used for combining the ground- and space-based temperature and humidity profiles. The first-guess profiles of temperature and humidity required by the physical retrieval algorithm are obtained by using a statistical inversion technique and the ground-based remote sensors measurements. Statistical error estimates are presented for the hourly, near-real-time, ...
... ice, hurricanes, and trees (less likely on high voltage transmission lines ) can bring down above ground power lines. Flooding, Leeching ground ...
Individual strains of the plant pathogenic bacterium Pseudomonas syringae vary in their ability to produce toxins, nucleate ice, and resist antimicrobial compounds. These phenotypes...Full Text Available
... Finally, the one dimensional, one phase Stefan problem is well known as a model for the melting of ice (see, eg, [5]). There are many approaches to ...
This article addresses the need for new data on indirect effects of natural and anthropogenic aerosol particles on atmospheric ice clouds. Simultaneous measurements of the concentration and composition...Full Text Available
Total concentrations of major and trace elements were determined in samples of the epilithic lichen Umbilicaria decussata from 24 ice-free areas in coastal ...
Jul 26, 2011 ... The Gateway to Astronaut Photography of Earth hosts the best and most complete online collection of astronaut photographs of the Earth.
estimates from 42 years of submarine records (19582000) described by ... area (DRA) of declassified submarine sonar measurements. (covering $38% of the ...
assessment.Both frustumswerein excellentcondition.No missingTPSor debonds/ unbondswere ...... 2) The average time for a 360 degree rotation was 29.9 seconds. ...
Earlier research by Zel'manov and by Hoenl and Dehnen has shown how the geodesic equation for a charged test particle can be written as a Lorentz force law in which the four-velocity u"i of an observer in the physical three-space #gamma#_#alpha#_#beta# = -g_#alpha#_#beta# + g_0_#alpha# g_0_#beta# / g_0_0 is regarded as a gravitational vector potential. Analysing this analogy further, we write the four ("i_0) components of the Einstein equations in a form resembling a non-linear Maxwell system, which, for a stationary field, is most clearly understood from the Kaluza-Klein perspective, the projection being from four dimensions to three, rather than from five dimensions to four. For the vacuum theory defined by vanishing energy-momentum tensor, T_i_j = 0, these equations exhibit the structure of a non-linear sigma model, found by Ernst, and investigated by Gibbons and Hawking and by Sanchez, the scalar potentials of which we here relate to the ...
We consider the spin-k/2 XXZ model in the antiferromagnetic regime using the free-field realization of the quantum affine algebra U_q(sl_2) of level k. We give a free-field realization of the type-II q-vertex operator, which describes creation and annihilation of physical particles in the model. By taking a trace of the type-I and type-II q-vertex operators over the irreducible highest-weight representation of U_q(sl_2), we also derive an integral formula for form factors in this model. Investigating the structure of poles, we obtain a residue formula for form factors, which is a lattice analog of the higher-spin extension of Smirnov's formula in the massive integrable quantum field theory. This result as well as the quantum deformation of the Knizhnik-Zamolodchikov equation for form factors shows a deep connection in the mathematical structure of the integrable lattice models and the massive integrable quantum field theory. ((orig.)).
Two types of switched electrode electronics beam position monitors are in use at Jefferson Lab. Together they provide accurate beam position to the control system for beam intensities between 50 nA and 2 mA. One version, called the linac style, has a switching frequency of 125 kHz. The other, called the transport type, has a switching frequency of 7 kHz. The basic system provides information to the control system at a 1 Hz update rate. The systems are regularly used to measure the AC component of beam position and energy as well as suppress this motion as part of a fast feedback system. Position data produced by the system are also acquired on an event by event basis as part of the nuclear physics program in two of the experimental halls. This paper will focus on the AC characteristics of the system. These characteristics are affected by analog filter frequencies and a time delay between the measurement of the positive electrode signal and the ...
The Linac Coherent Light Source (LCLS) is required to deliver a high quality electron beam for producing coherent X-rays. As a result, high resolution beam position monitoring is required. The Beam Position Monitor (BPM) digitizer acquires analog signals from the beam line and digitizes them to obtain beam position data. Although Matlab is currently being used to test the BPM digitizer?s functions and capability, the Controls Department at SLAC prefers to use Experimental Physics and Industrial Control Systems (EPICS). This paper discusses the transition of providing similar as well as enhanced functionalities, than those offered by Matlab, to test the digitizer. Altogether, the improved test stand development system can perform mathematical and statistical calculations with the waveform signals acquired from the digitizer and compute the fast Fourier transform (FFT) of the signals. Finally, logging of meaningful data into files has been added.
Dynamic Flowgraph Methodology (DFM) is a methodological approach to modeling and analyzing the behavior of software-driven embedded systems for the purpose of reliability/safety assessment and verification. The methodology has two fundamental goals: (a) to identify how certain postulated events may occur in a system and (b) to identify an appropriate testing strategy based on an analysis of system functional behavior. To achieve these goals, the methodology employs a modeling framework in which system models are developed in terms of causal relationships between physical variables and temporal characteristics of the execution of software modules. These models are then analyzed to determine how a certain state (desirable or undesirable) can be reached. This is done by developing timed fault trees, which take the form of logical combinations of static trees relating system parameters at different points in time. The prime implicants (multistate ...
Fluorescent microspheres were applied in a novel fashion during subsurface drilling of permafrost and ground ice in the Canadian High Arctic to monitor the exogenous microbiological contamination of...Full Text Available
The abundant microbial population in a 3,043-m-deep Greenland glacier ice core was dominated by ultrasmall cells (<0.1 μm3) that may represent intrinsically small organisms...Full Text Available
The reinforced concrete artificial iced course, constructed first in Japan as a bobsleigh and luge track for the Nagano Olympic Games, has a total extension of 1,700 m and an altitude difference of 113 m. It contains 15 curves and 2 up-grades and is divided into 43 blocks with spans ranging from 20 m to 80 m, all of which consist of lightwall RC members supported by pile foundations. The surface is cooled to -15 centigrade by the cooling pipes embedded in concrete and is iced by spraying water, and iced surface is shaved to make a course. Since the course scarcely has same profiles, the finished wall thickness is secured by fixing wire gauzes on the required positions without using shutterings. As there is not existed concrete satisfying all the required quality, two kinds of concrete were selected for filling in the arrangement of reinforcement and pipes and for surface finishing. Special notice was taken of the accuracy ...
Enzyme kinetic studies from this laboratory (M. Dobersen and S. Greer, Biochemistry 17:920-928, 1978) suggested that deoxycytidine could antagonize the toxicity of 5-halogenated analogs of deoxycytidine...Full Text Available
The first successful observation of double analog states in "8"8Zr and "9"0Mo has been made by means of the (#pi#"+,#pi#"-) pion double charge exchange (DCX) reaction. The systematics of the (N - Z) and the A dependence of analog DCX, made possible by these observations, is discussed. (orig.).
Equations are compiled for thermal balance in which for simplification, no consideration is made for heat conductivity along the axis of the cable and dependence of losses, heat capacitance and heat conductivity on temperature. Equations are modeled on a transistor analog calculator 42 TA. The solution to the task on the computer produced values of maximum temperature on the cable and coordinates of the point of maximum overheating. Using the analog model, one can study other parameters of the thermal mode.
Three analogs of lidocaine (benzyl carbamyl, benzyl nitrile and methyl nitrile) were synthesized and examined for cardiovascular and central activity. The benzyl carbamyl analog was more potent than lidocaine in lowering blood pressure but possessed only slight local anesthetic, antiarrhythmic and CNS-depressant activity. At 40 mg/kg the benzyl nitrile derivative was superior to lidocaine in protecting against chloroform-induced arrhythmias. The methyl nitrile analog was less active than the benzyl nitrile analog in most parameters examined. The benzyl nitrile derivative and lidocaine had similar potencies on blood pressure depression, local anesthetic activity and ability to protect against calcium chloride-induced arrhythmias. Unlike the benzyl carbamyl derivative both lidocaine and the benzyl nitrile compounds appear to depress the cardiovascular system via a common mechanism. PMID:515167
In this talk, we summarize recent results obtained from the combined neutrino telescopes IceCube and AMANDA. The combined approach, including data taken from both detectors simultaneously, is compared to other analyses that are using IceCube only data. The main benefit of the combined detector is its improved performance at low energies, meaning energies below 1 TeV (close to the energy threshold of the detector). The discussion is focused on the search for extra-terrestrial neutrinos from candidate sources in our Galaxy. Using appropriate cuts, the sensitivity can be optimized for soft spectra neutrino sources. With the resulting data sample, several studies are performed: an unbinned Galactic Plane Scan and a Cygnus region analysis: the Multi Point Source analysis. The current status of these analyses is presented.
A novel PCR based assay was devised to specifically detect contamination of any Salmonella serovar in milk, fruit juice and ice-cream without pre-enrichment. This method utilizes primers against hilA gene which is conserved in all Salmonella serovars and absent from the close relatives of Salmonella. An optimized protocol, in terms time and money, is provided for the reduction of PCR contaminants from milk, ice-cream and juice through the use of routine laboratory chemicals. The simplicity, efficiency (time taken 3-4 h) and sensitivity (to about 5-10 CFU/ml) of this technique confers a unique advantage over other previously used time consuming detection techniques. This technique does not involve pre-enrichment of the samples or extensive sample processing, which was a pre-requisite in mos...
Field investigations of major and damaging ice jamming on the Saint John River at Dickey, Maine , and at Sainte-Anne de-Madawaska, New Brunswick, in 1991, were described. The investigations included measurement of water surface profiles and shear wall heights at both sites. The measurements were supplemented by information from local observers and data collection agencies. Using a simplified equilibrium analysis, ice jam thickness and water level at the Dickey site was found to be generally in agreement with observed values. At Sainte-Anne-de-Madawaska sufficient data was obtained to construct and calibrate the numerical model RIVJAM which determined the configuration of the jam in nonequilibrium reaches. Use of the model enabled the successful reproduction of a measured water profile along the jam and the prediction of the approximate thickness of the jam, which was generally less than the measured shear wall height. 14 refs., 11 figs.
One of the refinements of modern Nuclear Medicine is the capacity of providing dynamic and kinetics images of the administered radiopharmaceutical, reproducing its transport mechanism, action sites, receptor binding and excretion route. With the continues technological advances new radiopharmaceuticals have been developed in order to express higher specificity and with higher characters of affinity between receptor/complex. One radiopharmaceutical is formed by a reagent or bio molecule that has in its structure a radioisotope, that has the objectives of carrying it to the organs of affinity or to benign or malign tumoral process. Somatostatin inhibits the growing and proliferation of several tumoral cells. Somatostatin analogs bind to somatostatic receptors that are expressed in different kind of neoplasia DOTA-LANREOTIDE (DOTALAN) is an octapeptide analog to somatostatin. The interest of labeling the bio conjugate with gallium-67 in Nuclear ...
The ice cover in high mountain lakes breaks up and disappears in about an hour, in part because it has been divided into fragile vertical spindles, which are individual crystals. Contributing to this...Full Text Available
TSS (thermal swing sublimation) method was studied which uses vaporization heat and sensible heat of LNG for solidification and separation of CO2 gas in waste gases of LNG-fired combined cycle power generation system. In experiment, the mixed gas composed of CO2, H2O and N2 was used for simulating waste gas of LNG-fired combined cycle power generation systems, and the growth behavior of ice and dry ice was studied for developing dry ice making technology under low-temperature condition. As the experimental result, the following were clarified: various crystal structures depending on cooling temperature, the effect of gas flow rate on peeling of surface precipitated solids, and solidification characteristics of H2O/CO2 mixed gas. The growth rate of precipitated solid film thickness decreased with an increase in gas flow rate, while increased with CO2 concentration. The shape of a dry ice sublimator ...
BackgroundRadiofrequency ablation (RFA) of tumors by means of internally cooled electrodes (ICE) combined with interstitial infusion of saline may improve clinical results. To date,...Full Text Available
time as well, due to the complex patterns of air movement taking place within cumulus clouds. ...... cumulative distribution of XPD, for rain and ice-particle induced ...... CCIR (1986f), Attenuation by Hydrometeors, In Particular ...
BackgroundEchocardiography has been debated as an adjunct for transcatheter aortic valve replacement (TAVR). The aim of this prospective study was to comparatively evaluate intraprocedural guidance using intracardiac echocardiography (ICE) and transesophageal echocardiography (TEE). MethodsFifty high-risk patients with severe aortic stenosis scheduled for TAVR were randomized to either guidance using ICE (group 1; n = 25) or monitoring using TEE (group 2; n = 25). ResultsIn contrast to TEE, ICE allowed continuous monitoring. The need for probe repositioning during the procedure was much lower in group 1 (0.1 +- 0.3 vs 5.7 +- 0.7 maneuvers, P P = .003). Both coronary ostia were more frequently visualized in group 1 (18 vs 2 cases, P n = 25, r2 = 0.90, P n = 11, P = .012), but ICE did not (m...
Records of past climates contained in ice cores, ocean sediments, and other archives show that large, abrupt, widespread climate changes have occurred repeatedly in the past. These changes were especially...Full Text Available
The Hebron offshore drilling project in Atlantic Canada was discontinued in 2002 due to economic challenges. Chevron-Texaco has conducted small-scale studies to find ways to improve the project's viability. One of the main challenges facing this offshore drilling project is the issue of iceberg scour and its effect on seafloor equipment. This paper demonstrates how advances in ice engineering have resulted in new and cost-effective development concepts for: central gravity base structures; wellhead gravity base structures; floating production, storage and offloading (FPSO) subsea facilities; and, long subsea tieback and trench optimization. New studies have provided a better understanding of ice contact pressures, drift velocities, iceberg management and interaction processes. New designs for gravity base structures can reduce wave loads. The selection of a new development concept is determined by economic viability, capital cost, ...
... say for sure if the signal is coming from hail, lots of graupel, or some other hydrometeor . ... Precipitation forms when cloud droplets or ice particles in clouds grow and .... A landslide is the movement of rock, debris, or earth down a slope. ...
Feb 15, 2008 ... hydrological properties (e.g., hydrometeor budgets, cloud ice/water, transports ... cloud fraction, mass and particle size. In combination, these .... anomaly in the LS is not simply due isentropic movement of water vapor relative ...
Bacteria and fungi are ubiquitous in the atmosphere. The diversity and abundance of airborne microbes may be strongly influenced by atmospheric conditions or even influence atmospheric conditions themselves...Full Text Available
The kinetics of HO{sub 2} radicals in UV-irradiated frozen dilute solutions of H{sub 2}O{sub 2} were followed by the ESR technique. Radical disproportionations at the irradiation temperature were found to be adequately described in terms of dispersive kinetics by a second-order equal-concentration kinetic equation with rate parameters changing non-monotonically in the temperature range 100-200 K. These changes are thought to occur due to well separated structural relaxation regions of polycrystalline ice in the above temperature range. (author).
The Dynamic Analog Scale (DAS) is introduced as a technique for generating single-item measures of personality traits. The DAS is comprised of extensive trait definitions and an analog scale on which respondents simultaneously rate themselves and others. In two studies the Big Five personality traits were assessed with the DAS and compared to a multiple-item questionnaire that measured the same traits. Statistical analysis supported the validity of the DAS for predicting self-reported behavioral acts, drinking behaviors, affect, and religiosity in ways similar to the multiple-item questionnaire. Consistent with previous research, both studies supported the viability of measuring personality traits with single items.
(e.g. enclosed cooktop with built in emissions capture and treatment) . " Test hardware in laboratory, reduced pressure and analog habitat. " Objective 1. ...
The classical Stefan problem describes the motion of a solidification front through a uniform half-space in response to a step change in temperature on its boundary. The predictions of such a model can be applied quite accurately to the freezing of water in a porous medium so long as the pore geometry remains unaltered by the passing solidification front. It is observed, however, that in fine-grained porous media, ice has a tendency to form in segregated horizontal bands, known as ice lenses, that disrupt the regular pattern of heat flow through their enhanced consumption of latent heat. This process, known as frost heave, causes significant ground deformation in regions subject to prolonged freezing, and is one of the most important weathering processes in polar and alpine regions. Recent improvements to our understanding of the mechanics of ice lens nucleation and growth are applied here to predict the conditions and ...
The characteristics of per-fluorocarbon compounds (PFC) are colorless, non-toxic, easily vaporized and nonflammable. Also, some of them are liquids of a high density, low surface tension, low latent heat and low specific heat. These particular chemical and physical properties of fluoro-organic compounds permit their use in very different fields such as electronics, medicine, tribology, nuclear and material science. The Sonatol process was developed under a contract with the DOE. The Sonatol process uses an ultrasonic agitation in a PFC solution that contains a fluorinated surfactant to remove radioactive particles from surfaces. Filtering the suspended particles allows the solutions to be reused indefinitely. They applied the Sonatol process to the decontamination of a heterogeneous legacy Pu-238 waste that exhibited an excessive hydrogen gas generation, which prevents a transportation of such a waste to a Waste Isolation Pilot Plant. Korea Atomic Energy Research ...
A pro-drug 8 of a synthetic analog 7 is more active in its anti-proliferative activity against human breast cancer MDA-MB-231 cells possessing high Catechol-O-methyltransferase...Full Text Available
Projected scenarios for the proposed Yucca Mountain repository include significant periods of time when high relative humidity atmospheres will be present, thus the reaction processes of interest will include those known to occur under these conditions. The ideal natural analog for the proposed Yucca Mountain repository would consist of natural borosilicate glasses exposed to expected repository conditions for thousands of years; however, the prospects for identifying such an analog are remote, but an important caveat for using natural analog studies is to relate the reaction processes in the analog to those in the system of interest, rather than a strict comparison of the glass compositions. In lieu of this, identifying natural glasses that have reacted via reaction processes expected in the repository is the most attractive option. The goal of this study is to quantify molecular water diffusion in the ...
There is a renewed interest in straight wing vertical axis wind turbines (SW-VAWT) which are usually installed on the roofs of high buildings in cities, urban areas and high mountain areas for independent electric power supply. SW-VAWTs have the advantages of simple design and low cost, as well as wind direction independence compared to the horizontal system. However, when SW-VAWTs are installed in cold regions, ice, snow and other attachments can affect its performance. In this study, clay was attached to the leading edge of the blade surface to determine how the performance of SW-VAWTs are affected by the mechanism of icing. Wind tunnel tests were used to study the rotational performance and power performance of the turbine blades. Icing prevention was also investigated. The attachment of clay on the leading edge of blade surface made the rotational performance of the SW-VAWT worse. The attachment of clay on the leading ...
The spin relaxation processes within the pyrochlore Ho{sub 2}Ru{sub 2}O{sub 7} have been investigated by neutron scattering and bulk property techniques. A single-ion process, that is thermally activated, dominates the spin-spin relaxation spectrum above 2 K. Assuming Arrhenius behaviour, we found an activation energy {delta} = (329 {+-} 6) K and characteristic relaxation time {tau}{sub 0} (5.2 {+-} 0.3) x 10{sup -12} s in the paramagnetic state, akin to those found in the spin ice, Ho{sub 2}Ti{sub 2}O{sub 7}. Atlow temperature (T<95 K) the activation energy lowers and below 20 K the entropy and ac susceptibility are similar to that observed in other spin ice compounds within a 10 kOe field.
The spin relaxation processes within the pyrochlore Ho_2Ru_2O_7 have been investigated by neutron scattering and bulk property techniques. A single-ion process, that is thermally activated, dominates the spin-spin relaxation spectrum above 2 K. Assuming Arrhenius behaviour, we found an activation energy #DELTA# = (329 #+-# 6) K and characteristic relaxation time #tau#_0 (5.2 #+-# 0.3) x 10"-"1"2 s in the paramagnetic state, akin to those found in the spin ice, Ho_2Ti_2O_7. Atlow temperature (T<95 K) the activation energy lowers and below 20 K the entropy and ac susceptibility are similar to that observed in other spin ice compounds within a 10 kOe field.
Objectives(i) Investigate the correlation between Antarctic sea-ice and equatorial sea-surface temperature anomalies in a realistically forced ocean model simulation of the last 50 years. (ii) Determine whether and how the enormous seasonal change in distribution of sea-ice modifies the seasonal cycle at the Equator. (iii) Determine the detailed pathways of wave propagation both in a historically-forced simulation and in response to realistic perturbations. (iv) Quantify the amplitude of the response i [continued...]DescriptionIt is well known that the equatorial ocean-atmosphere system plays a key role in global climate events such as the El Nino-Southern Oscillation (ENSO) phenomenon. There is now compelling evidence that changes in the Antarctic can strongly and quickly affect the equatorial ocean and the ENSO cycle. Observations demonstrate statistically significant correlations (teleconnections) between the Antarctic and the Equator with ...
Inverse and direct methods have been used to analyze a large number of borehole temperature logs in order to infer past climatic changes. Results indicate a warming of 1-2[degree]C in eastern and central Canada during the past 150 years. A period of cooling between 500 and 200 years before present, corresponding to the time of the Little Ice Age, has also been identified in the same areas. A regional ground temperature history is estimated for eastern and central Canada from the simultaneous inversion of several temperature logs. The inferred temperature changes appear correlated with the concentration of atmospheric carbon dioxide as reported from a Greenland ice core, and agree with existing meteorological and dendrochronological records for the area.
During sporting events, injured athletes often return to competition after icing because of the reduction in pain. Although some controversy exists, several studies suggest that cryotherapy causes a decrease in muscle activity, which may lead to a higher risk of injury upon return to play. The purpose of this study was to investigate the effect of a 20-min knee joint cryotherapy application on the electromyographic activity of leg muscles during a single-leg drop jump in twenty healthy subjects, randomly assigned to an experimental and a control group. After the pre-tests, a crushed-ice bag was applied to the knee joint of the experimental group subjects for 20min, while the control group subjects rested for 20min. All subjects were retested immediately after this period and retested again...
In certain regions of the sea floor, water and methane from organic depositions have turned into a burnable form of ice, i.e. methane hydrates which contain more stored energy than all fossil fuel reserves. If they should desintegrate as a result of global heating, methane will be released and will contribute to further global heating. [Deutsch] Im Boden bestimmter Meeresregionen haben sich Wasser und Methan aus organischen Ablagerungen zu einer brennbaren Form von Eis vereinigt. Diese Methanhydrate speichern mehr Energie als alle fossilen Brennstoffvorraete. Wenn sie sich bei einer globalen Erwaermung zersetzen, koennte das entweichende Methan als Treibhausgas die Erde noch mehr aufheizen. (orig.)
Two no-carrier-added "1"2"5I-labelled photoaffinity rapamycin analogs were prepared: 7-demethoxy-7-(4-azido-3-"1"2"5I-benzyloxy) rapamycin and its C_2_8-C_2_9 seco analog. The key reactions of the synthesis were substitution of the C_7 methoxyl of rapamycin with 4-azido-3-tributylstannylbenzyloxy group, exchange of tributyltin with "1"2"5I using Na"1"2"5I and Chloramine-T, and a ZnCl_2 mediated retro-Aldol cleavage of the C_2_8-C_2_9 bond of rapamycin. (author).
An analysis is made of the basic principles and methods of construction of integrated optical circuits (IOC) for data processing, which are optical waveguide processors in the integrated form. A classification is provided of IOC in accordance with the nature of the input connections to optical components and in accordance with their intended function. An analysis is made of the current status of research and development of analog IOC for handling analog and digital signals, IOC for computing technology, and switching IOC. A detailed analysis is made of IOC with different functions in data processing: spectrum analyzers and correlators, analog-digital converters, circuits for identification of data sets and for encoding of signals, threshold and multistable circuits, logic and arithmetic units, and switching arrays. Descriptions are given of IOC for optically controlled data handling: bistable purely optical logic circuits, ...
An experimental and theoretical study of heat and mass transfer analogy and a comparison of that to a binary liquid mixture evaporation is presented. Common organic solvents, ethanol and n-heptane, were used to form an alcohol - hydrocarbon mixture. Studies were carried out in a horizontal rectangular channel having air flow velocities of 0.2 - 0.9 m/s. Heat transfer coefficients were measured with a copper plate resistor and mass transfer coefficients with a square pool. The heat and mass transfer analogy is presented for a system having two evaporating compounds with a fixed value of air flow and verified by measuring and comparing mass transfer coefficients for distilled water with air flow velocities of 0.2 - 0.9 m/s. An illustrative example of the use of the theory for industrial ventilation is presented. (author)
Digital audio sampling is explained, and some of its implications in digital sound applications are discussed. Digital sound equipment is rapidly replacing analog recording devices as the state-of-the-art in audio technology. The philosophy of digital recording involves doing away with the continuously variable analog waveforms and turning the patterns into numbers. A digital recording device rapidly samples the incoming sounds, quantifying the signal into a series of numerical values (binary codes). Although digital sound eliminates many of the traditional analog problems, digital signal processing presents key problems in sampling rates and synchronization. Careful control is necessary to check signals through each step in the audio chain. The advantages of digital audio processing include increased signal-to-noise ratio, no flutter, transparent generation of copies, and sound manipulation. These benefits come with ...
The FVM-LES-acoustic analogy method (FVM-LES-AAM), which is a hybrid prediction technique for the acoustical property computation, is presented and performed in this paper. The FVM-LES-AAM was developed by combining the finite volume method (FVM), the large eddy simulation (LES), and the Ffowcs Williams-Hawkings analogy algorithm (FWH-AA). To predict the acoustical properties of induction cookers, the FVM is used for discretizing the calculation field and building numerical equations, and the LES and FWH-AA are performed for computing the sound sources and predicting the far-field sound, respectively. Using the FVM with the unstructured grids method to discretize the control equation of Navier-Stokes was introduced for illuminating the above numerical simulation procedure. To prove the FVM...
The mechanisms involved in the glacial inception are still poorly constrained due to a lack of high resolution and cross-dated climate records at various locations. Using air isotopic measurements in the recently drilled NorthGRIP ice core, we show that no evidence exists for stratigraphic disturbance of the climate record of the last glacial inception ({proportional_to}123-100 kyears BP) encompassing Dansgaard-Oeschger events (DO) 25, 24 and 23, even if we lack sufficient resolution to completely rule out disturbance over DO 25. We quantify the rapid surface temperature variability over DO 23 and 24 with associated warmings of 10{+-}2.5 and 16{+-}2.5 C, amplitudes which mimic those observed in full glacial conditions. We use records of {delta}{sup 18}O of O{sub 2} to propose a common timescale for the NorthGRIP and the Antarctic Vostok ice cores, with a maximum uncertainty of 2,500 years, and to examine the interhemispheric sequence of events ...
The effect of open pit mine motor transport with ICE on the air basin is examined using the example of shale mines and open pits of the production association ''Estonslanets''. Efficient areas of use of different types of open pit mine motor transport, diesel-trolley tracks and electric cars are determined based on technical-economic and ecologic feasibility.
We developed a model for radar scattering from the lunar reoglith layer using vector radiative transfer theory. From this model, both the radar backscattering coefficient and the circular polarization ratio can be predicted analytically as a function of regolith parameters.
...in your blue fuller says global warming summit on the top general information ...this because a lot of times when we talk about global warming and climate change we really focus on the ice ...site ? one organization is called global warming one-on-one and it's run by ...can actually go to global warming one-on-one and and ...something to ? slow global warming but sometimes you feel alone so the big deal if i changed my life ...
Greenland is the world's largest island, with an area of 2.2 million square kilometres, 80 % of which is covered by the ice sheet. The climate is Arctic, but as Greenland stretches 2600 km from north to south, there is a huge variability in climate, with temperature decreasing from south to north. Due to the influence of oceanic currents, the west coast is slightly warmer than the east coast. Precipitation also decreases strongly from the south to the north, and also with distance from the coast. Kangerlussuaq is located in the dry, continental area of central west Greenland. The bedrock of Greenland is dominated by Precambrian gneisses, with sedimentary rocks occurring in some areas of East and North Greenland, and smaller areas of basalts. All of Greenland has been glaciated several times and has thus been eroded and shaped by the ice, as it still is at the ice margin. Soils are generally thin, and especially in the ...
The classical Stefan theory for the melting of a solid or the freezing of a liquid is too simplistic to describe phenomena such as supercooling, in which a liquid supports temperatures below its freezing point, or superheating, the analog for solids, or d...
Background:Several studies suggest transient ischemic attack (TIA) may be neuroprotective against ischemic stroke analogous to preinfarction angina's protection against...Full Text Available
Mitochondria and peroxisomes execute some analogous, nonredundant functions including fatty acid oxidation and detoxification of reactive oxygen species, and, in response to select metabolic cues, undergo...Full Text Available
A Monte Carlo simulation of the vacuum Bianchi type-IX (mixmaster) cosmology yields a significant correlation between large universe volume and high anisotropy. An analog of the model's chaotic classical behavior is seen in the break up of the universe wave function at large volume into fingers in the corners of the minisuperspace anisotropy potential.
Specificity of the pulses mean frequency measurement (the pulses being generated in a stochastic process) is described. Status of the domain of analog frequency meters is presented. Methods of increasing accuracy of such meters are discussed.
Specificity of the pulses mean frequency measurement (the pulses being generated in a stochastic process) is described. Status of the domain of analog frequency meters is presented. Methods of increasing accuracy of such meters are discussed. (author).
Antagonists for kainate receptors (KARs), a family of glutamate-gated ion channels, are efficacious in a number of animal models of neuropathologies, including epilepsy, migraine pain, and anxiety....Full Text Available
Juvenile hormone analog (JHA) insecticides are relatively nontoxic to vertebrates and offer effective control of certain insect pests. Recent reports of resistance in whiteflies and mosquitoes demonstrate...Full Text Available
The cyclohexane-1,2-diamine-based bisbinaphthyl macrocycles (S)-/(R)-5 and their cyclic and acyclic analogs are synthesized. The interactions of...Full Text Available
The phenomena and effects of airblast, ground shock, thermal radiation, cratering and ejecta, and debris cloud and deposition from the eruption of Mt. St. Helens were compared to those that would result from a nuclear explosion to determine if phenomena or effects were analogous and thus might provide useful data for military nuclear weapon effects studies. It is concluded that the phenomena are not analogous. In particular, airblast destruction was caused by clouds of ash driven by subsonic winds, rather than by a supersonic shock wave that would be the damage mechanism of a nuclear explosion. Because of the lack of analogy between the eruption and nuclear explosion phenomena, it appears questionable that any of the effects are analogous; therefore, it is unlikely that anything more of military interest can be gained from studying the effects of the eruption. However, key contacts for further ...
An approach to generate mimics of phosphorylated serine proteins chemically through site-specific sulfonation of cysteine is presented. This chemical modification is reversible in the presence of reducing agent and therefore is analogous to the kinase/phosphatase system used in nature. PMID:21717004
Early simian virus 40-specific mRNA was isolated from lytically infected and stably transformed cells and analyzed with respect to the 5'-terminal cap content. An analogous diversity of capped structures...Full Text Available
The tendency for some individuals to partake in high-risk behaviors (eg, substance abuse, gambling, risky sexual activities) is a matter of great public health concern, yet the characteristics and neural...Full Text Available
The CD1 family of proteins binds self and foreign glycolipids for presentation to CD1-restricted T cells. To identify previously uncharacterized active CD1 ligands, especially those of microbial origin,...Full Text Available
The risk analysis was carried out in consideration of conditions prevailing at the Kalkar site analogous to the investigations in phase A of DRS (German Reactor Study). Earthquake design loads include the probabilities of upper deviations of the site intensities to be expected. The calculations of dynamic loads for select buildings are made using models and computational methods. Component analyses were performed analogous to DRS for the supports of large components, supports of the roof construction of the reactor building taking into account support reserves due to plastic work capacity, wall disks in steam generator buildings and switchboard plant buildings. (DG).
The digital AVR must have the level of redundancy and control functions that conform to the configuration of the excitation control system and to the importance of a particular generator for the user. The digital AVR is not simply a digital version of the analog AVR, but can realize sophisticated control functions that were difficult to achieve with analog circuits, thus making it possible to enhance the stability of power system by PSS (power system stabilizer). This paper describes the test results of the digital AVRs applied to power plants, their system configuration and functions, as well as the outline of an auto-tuning PSS or AT-PSS planned to be incorporated in the digital AVR in the future.
A series of pyrrolo[2,3-d]pyrimidine-2,4-diones and intermediates was tested for anticonvulsant activity in mice. Eleven of the 15 compounds possessed anticonvulsant activity against pentylenetetrazol-induced convulsions. One compound afforded more anticonvulsant protection against pentylenetetrazol than did trimethadione (67 and 50%, respectively). A suspension of this compound was found to be as effective as a solution in producing anticonvulsant activity. The results suggest that the nitrile analogs were more potent compared to the carbamyl analog due to higher lipid solubility. PMID:7373552
Recent achievements and tendency on reactor physics activities in Japan are reviewed according to topics published in journals or discussed at the Japan Research Committee on Reactor Physics.
This course is based upon lectures in physics given by Professor Feynman at the California institute of technology during 1961 and 1962. This volume is dedicated to quantum physics, semiconductors, symmetry and advanced principles of physics.
... or she will start intensive rehabilitation. This includes physical therapy and occupational therapy. Physical and occupational therapies aim at strengthening the remaining ...
An approximate solution was proposed in which a sensitivity analysis by the storage and release of heat was performed for the subject issues and in which an operating method was thereby determined for the equipment constituting the system by means of a linear programming. Accordingly, a heat storage type energy supply system for a district cooling and heating was taken up as a concrete object to be examined. This system consisted of a gas turbine generator, initial power receiving equipment, gas boiler, electric heat pump for ice heat storage, cooling tower, heat exchanger, steam absorbing refrigerating machine, ice heat storage tank, cold and warm water heat storage tank, etc. As a result of comparison between the proposed method and the resolving method, the former showed -0.92 to 2.58% in the increase in the operating cost compared with the latter. A case where the operating cost of the resolving method was sometimes larger than the proposed ...
ObjectivesThe overall scientific aim of this project is, through development of an appropriate numerical modelling tool, to identify and investigate the mechanisms that control the current observed rapid thinning and acceleration of Greenland outlet glaciers and to investigate their likely future behaviour in the context of climate warming. This aim is addressed through the four major specific objectives below. These objectives build on each and therefore the order of priority is driven by the order in wh [continued...]DescriptionCurrently, the Greenland ice sheet is undergoing rapid changes in the coastal regions which have been attributed to a general warming trend to the regions climate over the last decade. Several of the narrow and fast flowing outlet glaciers that drain the ice sheet into the sea are observed to have accelerated their flow and thinned. For instance, Jakobshavn Isbrae on the West coast of Greenland has almost doubled its ...
Glacier fluctuations exclusively due to internal variations in the climate system are simulated using downscaled integrations of the ECHAM4/OPYC coupled general circulation model (GCM). A process-based modeling approach using a mass balance model of intermediate complexity and a dynamic ice flow model considering simple shearing flow and sliding are applied. Multi-millennia records of glacier length fluctuations for Nigardsbreen (Norway) and Rhonegletscher (Switzerland) are simulated using auto-regressive processes determined by statistically downscaled GCM experiments. Return periods and probabilities of specific glacier length changes using GCM integrations excluding external forcings such as solar irradiation changes, volcanic or anthropogenic effects are analyzed and compared to historical glacier length records. Preindustrial fluctuations of the glaciers as far as observed or reconstructed, including their advance during the ''Little ...
This paper presents an analysis of the applicability of alternative systems for electric vehicle (EV) heating and air conditioning (HVAC). The paper consists of two parts. The first part is a cooling and heating load calculation for electric vehicles. The second part is an evaluation of several systems that can provide the desired cooling and heating in EVs. These systems are ranked according to their overall weight The overall weight is calculated by adding the system weight and the weight of the battery necessary to provide energy for system operation. The system with the minimum overall weight is considered to be the best, because minimum vehicle weight decreases the energy required for propulsion, and therefore increases the vehicle range. Three systems are considered as the best choices for EV HVAC. These are, vapor compression, ice storage and adsorption systems. These systems are evaluated, including calculations of system weight, system volume, and COP. The ...
The AMANDA-II data collected during the period 2000-2003 have been analysed in a search for a diffuse flux of high-energy extra-terrestrial muon neutrinos from the sum of all sources in the Universe. With no excess events seen, an upper limit of E{sub {nu}}{sup 2} xs dN{sub {nu}}/dE{sub {nu}} < 7.4 x 10{sup -8} GeV cm{sup -2} s{sup -1} sr{sup -1} was obtained. The sensitivity of the diffuse analysis of IceCube 9 string for 137 days of data is calculated to be E{sub {nu}}{sup 2} x dN{sub {nu}}/dE{sub {nu}} < 1.3 x 10{sup -7} GeV cm{sup -2} s{sup -1} sr{sup -1}. No excess events are observed, which confirms the AMANDA-II upper limit.
There are many requirements for cost analysis and estimating within the Department of Energy (DOE). As projects go through the many stages of planning, source evaluation and selection, contracting, and construction, different estimating requirements exist and different techniques are available to the estimator. This cost guide illustrates how quantity takeoff estimating is performed when adequate design data are available, and it shows how statistics can be applied to obtain parametric cost estimates. Parametric techniques will become increasingly useful as the Department's cost data base and Cost Estimating Relationships (CERs) are developed. Other cost guides developed by the Independent Cost Estimating (ICE) Staff will be published and disseminated soon. The section on parametric cost estimating uses Department of Defense examples since the ICE Staff considered this information to be some of the best available on this subject. Also, ...
Penicillium crustosum is common in food and feed both in subtropical and temperate regions. Recently, it has also been found occurring frequently in glacier ice, sea ice and sea water of Arctic regions of Svalbard. The aim of the study was to compare isolates of the same fungal species from widely different habitats and geographic regions to see if the nutritional physiology and the profile of secondary metabolites were consistent or depended on the isolation source. All 121 strains examined produced the following families of secondary metabolites: penitrems (100%), roquefortines (100%), terrestric acids (99.2%) and viridicatols (100%), whereas 81 of 83 Arctic isolates additionally produced andrastin A. However, only 8 of 38 non-Arctic isolates produced detectable andrastin A. The quantitative profiles of 96 strains were compared using cluster, principal component and correspondence analyses. There was no clear grouping of Arctic versus ...
This document presents our proposal to continue the activities of Boston University researchers in eight projects in high energy physics research: Colliding Beams Physics; Accelerator Design Physics; MACRO Project; Proton Decay Project; Theoretical Particle Physics; Muon G-2 Project; and Hadron Collider Physics. The scope of each of these projects is presented in detail in this paper.
The Terra Nova offshore oil project is described, with emphasis on the construction of the Terra Nova Floating Production Storage and Offloading (FPSO) vessel, the first such vessel constructed for the harsh environment of the North Atlantic off Newfoundland, the site of an oil field that is expected to produce 125,000 to 150,000 barrels of oil per day starting in 2001. The vessel has a double-hull, made of 3,000 tons of reinforced steel to protect it from ice in the form of massive icebergs or crusty 'packs'. The vessel has the world's largest quick release turret, meaning that the vessel can be quickly disconnected from its turret and mooring in the event of an encroaching iceberg, and then reconnected in an environmentally sound way. Apart from its extremely rugged construction, protecting the FPSO vessel against icebergs is accomplished by way of 'hosing down' (by melting by powerful streams of water) or ...
ObjectivesNot EnteredDescriptionMethane hydrate in an ice-like substance consisting of molecules of methane gas combined chemically with water. It is stable at high pressures and low temperatures. Since the ocean floor is normally cold, but temperatures increase with depth inside the Earth, such conditions normally prevail for a few hundred meters below the seafloor where the ocean depth is more than a few hundred metres. Methane beneath the ocean floor is formed by the decomposition of organic material. At the edges of the co [continued...
Recently, a superconducting cryo-electron microscope in which specimens are cooled to the liquid helium temperature (4.2 K) has been developed. The main components and functional features of this new microscope are reported together with application data on polyethylene, poly (4-methyl-1-pentene), valonia cellulose, rock salt, ice crystallites and ceramic superconductor. The resistance to electron radiation damage, of beam-sensitive specimens including polymers has been increased more than ten times. Thus, the microscope has made it possible to take high resolution images and to analyze the crystal-structure of micro-areas. (orig.).
This work contains 27 chapters which cover recent advances in fracture mechanics applied to cement-based composites: concrete, reinforced concrete, and fiber reinforced concrete. The book, based on a NATO Advanced Study Institute, is a comprehensive survey of treating nonlinearity associated with crack growth in brittle materials such as cement composites, rocks and ice. The book is divided into 8 major themes: advances in nonlinear fracture mechanics; fracture processes; numerical modelling of fracture; experimental methods of determining fracture parameters; damage and continuum modelling; strain-rate and dynamic effects of crack propagation; stress-corrosion, time and temperature effects on fracture; and implications for concrete structures.
In one of the first uses of high Tc superconductors in an end-use product, Lake Shore Cryotronics and a Swiss lab have developed a liquid nitrogen level sensor using a high Tc thin film. The probe is manufactured using a seamless stainless steel tube with an yttrium-based zirconium oxide flame-sprayed on the tube. A plasma-sprayed superconductor compound is deposited on top of that. The probe is coated with a sealant that protects the superconducting film from the atmosphere. This manufacturing method has yielded an extremely durable product. Unaffected by ice formation and related mechanical problems, the superconducting level sensor can be kept in the dewar for long periods of time.
We explore the impact of obliquity variations on planetary habitability in hypothetical systems with high mutual inclination. For the hypothetical systems, we restrict our exploration to systems consisting of a solar-mass star, an Earth-mass planet at 1 AU, and 1 or 2 giant planets. We verify that these systems are stable for 108 years with N-body simulations. We then calculate the obliquity variations induced by the orbital architecture on the Earth-mass planets. We find that in some cases the spin axes can rotate through 360 degrees in as little as 10,000 years (John is that right? Can you look through the systems and find the most extreme case of obliquity variation?) Next, we run energy balance models (EBM) on the terrestrial planets to assess surface temperature and ice coverage on the planets' oceans. Finally, we explore differences in the outer edge of the habitable zone for planets with rapid obliquity variations. We run EBM simulations for a range of ...
An increased use of floating production facilities for offshore oil production in the past fifteen years was due in part to advances in technology, the opening of new frontiers and the increased emphasis on value driven development. Throughout the world, a total of 121 floating production systems were in operation in February 2001, and orders had been placed for an additional 27. Located near the nose of the Grand Banks, approximately 350 kilometres east-southeast of St. John's, Newfoundland is the Terra Nova development. Twelve years elapsed between the discovery of the field in 1984 and the granting of the approval for development in 1996. The decision was made to use a floating production system as the Terra Nova was not considered robust enough to support a gravity base, ice resistant structure development concept, especially considering that it came on the heels of the Hibernia development. The first Floating Production, Storage and Offloading (FPSO) ...
For most cells there exists an optimum cooling rate. Both supraoptimal rates and suboptimal rates can be very damaging. The optimal rate varies enormously from less than or equal to 1/sup 0/C/min for mammalian preimplantation embryos to greater than or equal to 800/sup 0/C/min for the human red cell. Death at supraoptimal rates is the result of the formation of intracellular ice and its recrystallization during warming. Intracellular ice occurs when cells are cooled too rapidly to allow them to equilibrate by the osmotic withdrawal of intracellular water. The definition of too rapid depends chiefly on the size of the cell and its permeability to water. Death at suboptimal rates is a consequence of the major alterations in aqueous solutions produced by ice formation. The chief effects are a major reduction in the fraction of the solution remaining unfrozen at a given temperature and a major increase in the solute ...
We present 14 years of contemporaneous photometric and spectroscopic observations of 28 solar analog stars, taken with the Tennessee State University Automatic Photometric Telescopes at Fairborn Observatory and the Solar-Stellar Spectrograph at Lowell Observatory. These are the best observed and most nearly Sun-like of the targets in our magnitude-limited (V #<=# 7.5) sample. The correlations between luminosity and activity reveal the expected inverse activity-brightness correlations for active stars. Strong direct correlations between activity and brightness are not prevalent for the less active solar age stars, but are precision limited. The Sun does not appear to have unusually low photometric variability when compared with the most Sun-like inactive solar analogs. We present evidence that the activity index R'_H_K is not a good discriminant of Maunder Minimum candidate stars. On the basis of a star that appears to have transitioned from ...
Targeted studies completed include the evaluation of tritiated N-0437, evaluation of "3"5S-cysteamine, evaluation of "1"8F-FDG and initiation of synthetic efforts towards the synthesis of iodinated N-0437 and pergolide analogs. The direction of the project has been changed due to several factors which include the decided lack of favorable experimental results, the excellence of results using muscarinic receptor ligands in pituitary, brain and heart and the contention of the DOE review panel that the original grant proposal was based on flawed assumptions together with their perceived lack of importance to pituitary imaging. In the final year of this grant, three studies will be completed. The first study is the continuation of synthetic efforts to prepare iodinated N-0437 and pergolide analogs for possible use as brain imaging agents. The second study is directed towards completion of biochemical evaluation of various muscarinic receptor ...
Targeted studies completed include the evaluation of tritiated N-0437, evaluation of /sup 35/S-cysteamine, evaluation of /sup 18/F-FDG and initiation of synthetic efforts towards the synthesis of iodinated N-0437 and pergolide analogs. The direction of the project has been changed due to several factors which include the decided lack of favorable experimental results, the excellence of results using muscarinic receptor ligands in pituitary, brain and heart and the contention of the DOE review panel that the original grant proposal was based on flawed assumptions together with their perceived lack of importance to pituitary imaging. In the final year of this grant, three studies will be completed. The first study is the continuation of synthetic efforts to prepare iodinated N-0437 and pergolide analogs for possible use as brain imaging agents. The second study is directed towards completion of biochemical evaluation of various muscarinic ...
A high sensitivity (titer 60-150,000) radioimmunoassay for arginine vasopressin (AVP) has been developed using synthetic AVP as antigen and standard. The specificity of the antiserum has been characterized in detail by measuring the relative binding affinities of 29 analogs and fragments of AVP. In general, single amino acid substitution or deletion in the AVP molecule caused a reduction in binding to the antiserum; binding was further impaired for analogs which had multiple substitutions. ''Ring'' and ''tail'' fragments of the neurohypophysial hormones did not bind to the antiserum, and the only analog which the antiserum could not differentiate from AVP was deamino-AVP. More specifically, the antiserum exhibited the following properties: position 1, no requirement for a position charge at "1/_2 Cys; positions 2 and 3, requirements for #pi#-#pi# interacting pair of aromatic side chains and for Tyr at position 2; position ...
The authors report experimental results of heat transfer in the region of transition to turbulence. The augmentation was induced through deployment of periodically placed cylindrical eddy promoters in parallel plane channel flows. Eight different configurations were used. The presence of eddy promoters displaced the point of transition from Reynolds number values of 1500 for the plane channel to around 400 for the least stable case. The value of Nusselt number at the transition for eddy promoters cases was up to 2.5 times higher than the one for the plane channel at the transition. Furthermore, the lower the transition Reynolds number, the higher the Nusselt number at the transition. For the cases where the diameter of the promoters was small and/or the pitch large, the heat transfer results in the transition region were consistent with values obtained from the Reynolds analogy when the analogy was based on the mean transport parameters, i.e., ...
A computer was built for use with the NRU reactor to solve the problem of Xe/sup 135/ concentrations. The effect of any changes in reactor on Xe/sup 135/ concentration can be predicted and steps taken to avoid poisoning out. An electromechanical system was used for the computer to avoid the inherent disadvantages that electronic analog computers present for problems of very long solution times. The electromechanical analog computer has a high order of reliability and contains no vaccum tubes, commutators, slip rings, relays, or aluminum electrolytic capacitors. It is insensitive to transient disturbarce. In the event of failure of components or interruption of line voltage, it will retain existing information. The computer was designed for ~ 1% accuracy in Xe/ sup 135/ concentration readings. (W.D.M.)
The radionuclide X-ray fluorescence analyzer consists of a source changer and a sample changer. "5"5Fe, "1"0"9Cd and "2"4"1Am are used as excitation sources. The radiation is detected with a semiconductor Si(Li) detector. The complete assembly of the apparatus consists of an imagine unit, a keyboard, a floppy disc drive, a printer, a console and a rack with analog and digital electronics. Its multichannel amplitude analyzer consists of power supplies, a high voltage supply, a linear amplifier, an analog-to-digital converter and a computer. The technical specifications are given. The control and data processing system is controlled with an MHB 8080A microprocessor. Software for semiconductor gamma spectrometry and for quantitative gamma spectrometry will be supplied with the equipment. (E.S.). 3 figs., 4 refs.
Sulfur mustard (HD) is an alkylating and cytotoxic chemical warfare agent, which inflicts severe skin toxicity and an inflammatory response. Effective medical countermeasures against HD-caused skin toxicity are lacking due to limited knowledge of related mechanisms, which is mainly attributed to the requirement of more applicable and efficient animal skin toxicity models. Using a less toxic analog of HD, chloroethyl ethyl sulfide (CEES), we identified quantifiable inflammatory biomarkers of CEES-induced skin injury in dose- (0.05-2 mg) and time- (3-168 h) response experiments, and developed a CEES-induced skin toxicity SKH-1 hairless mouse model. Topical CEES treatment at high doses caused a significant dose-dependent increase in skin bi-fold thickness indicating edema. Histopathological e...
Statement of problem Although the esthetic outcome of a collarless metal ceramic restoration is superior to that of a restoration with a metal margin, its mechanical strength has not been evaluated. Purpose The purpose of this study was to evaluate and compare the fracture resistance of metal ceramic restorations with metal margins to that of metal ceramic restorations with circumferential porcelain margins, after exposure to masticatory simulation. Material and methods Twenty-four metal ceramic restorations were fabricated and paired with 24 cobalt-chrome tooth analogs. Twelve of the specimens had metal margins, while the remainder had circumferential porcelain margins. The restorations were cemented on the metal tooth analogs with a resin-modified glass ionomer luting agent (FujiCEM). Al...
Thioredoxin reductase (TrxR) isoforms play important roles in cell physiology, protecting cells against oxidative processes. In addition to its endogenous substrates (Trx isoforms), hepatic TrxR can reduce organic selenium compounds such as ebselen and diphenyl diselenide to their selenol intermediates, which can be involved in their hepatoprotective properties. Taking this into account, the aim of the present study was to evaluate the hypothesis that ebselen, diphenyl diselenide and its analogs (4,4'-bistrifluoromethyldiphenyl diselenide, 4,4'-bismethoxydiphenyl diselenide, 4.4'-biscarboxy-diphenyl diselenide, 4,4'-bischlorodiphenyl diselenide, 2,4,6,2',4',6'-hexamethyldiphenyl diselenide) could be substrates of rat brain TrxR. In the presence of partially purified rat brain TrxR, dipheny...
A consideration is given to the problem of selecting optimized methods of radionuclide radiation registration during the control of the objects with essential changes in thickness. Adequate model of information signal formation is developed and analyzed for the case of the existence of an inertial link of the system with the dead time of a noncontinued type. The boundary values of radiation thickness and radiation flux intensity that divide the priority of using either digital or analog registration modes are revealed. The method is found for the full correction of a systematic error of flux intensity measurement because of the dead time of the apparatus. To control the objects with essential variation of thickness the method of selective measurement of radiation intensity is proposed
Polysilicon thin-film technology has become of great interest due to the demand for large area electronic devices. Active matrix liquid crystal displays (AMLCDs) and active matrix organic light emitting displays (AMOLEDs) are among the fields where polysilicon thin-film transistors (poly-Si TFTs) are most commonly used. Such devices, generally, require analog signal processing. This fact makes the performance of basic analog blocks, such as current mirrors implemented with poly-Si TFTs, crucial. This paper examines the performance of various current mirror designs through simulation. Finally, a novel design of a current mirror is proposed aimed to be used in low voltage applications.
The problem on the ratio between the instability of physical systems and tachyons is discussed. It is shown that the tachyons participation in the real physical process of the system rearranging does not contradict any principles. It is noted that the tachyons constitute the most significant element of the systems, identifying the instability relative to the phase transition into the stable state.
Lifetime exposure to physical activity is an important construct for evaluating associations between physical activity and disease outcomes, given the long induction periods in many chronic diseases....Full Text Available
Background and objectives: Chronic kidney disease (CKD) is associated with impaired physical activity. However, it is unclear whether the associations of physical activity with mortality are modified...Full Text Available
Given the high prevalence of overweight and low levels of physical activity among children, a better understanding of physical activity behaviour is an important step in intervention planning. This...Full Text Available
BackgroundAnhedonia towards physical or sensory experiences (i.e., physical anhedonia) has most often been examined as a differentia of schizophrenia and not depression,...Full Text Available
The essential properties of tachyons are described briefly and the 'reinterpretation principle' for tachyons is discussed. The possibility of conducting an experiment analogous to the Michelson-Morley experiment in which a preferred frame may be detected is considered. The existance of a tachyon prefered frame is consistent with the principles of relativity and, if suitable experiments were devised, could provide important evidence for the existence of tachyons. (W.D.L.).
The dependence of Tsub(c) on composition and deformation is calculated and compared with the corresponding dependence for Tsub(m). It is shown that superconducting and structural properties of A-15 compounds can be described, at least qualitatively, by the quasi-one-dimensional model previously developed by the authors. The superconductivity mechanism is assumed to be analogous to the BCS theory. The upper critical field Hsub(c2) of the V_3Si or Nb_3Sn compounds is found to be much greater than that in V or Nb.
A technique for measurement of the energy spectra of fission fragments is discussed. The fine structure found in the spectra of fragments from spontaneous fission of {sup 242}Cm and fast-neutron fission of {sup 242{ital m}}Am is analyzed. The quantitative parameters of the structure and their analogy with the characteristics of cold fission are discussed.
Bridged monobactam {beta}-lactamase inhibitors were prepared and evaluated as potential partners for combination with imipenem to overcome class C {beta}-lactamase mediated resistance. The (S)-azepine analog 2 was found to be effective in both in vitro and in vivo assays and was selected for preclinical development.
Plants often synthesize secondary metabolites that are enantiomers. Enantiomers can cause very different physiological responses. Ammodendrine (1) and anabasine (2) are teratogens that can cause congenital malformations in livestock and enantiomeric forms of each have been found in Lupinus spp. an...
The polysaccharide components from cultured cells of Rhizobium fredii USDA205 and Rhizobium meliloti AK631 were extracted with hot phenol-water and separated by repetitive gel filtration chromatography....Full Text Available
A renormalization procedure is proposed which applies to lattice Feynman integrals containing zero-mass propagators and is analogous to the BPHZL renormalization procedure for continuum Feynman integrals. The renormalized diagrams are infrared convergent for non-exceptional external momenta, if the vertices of the theory satisfy a general infrared constraint. Under the same conditions as in the massive case, the continuum limit of the renormalized theory exists and is independent of the details of the lattice action.
A Monte Carlo simulation of the vacuum Bianchi type-IX (mixmaster) cosmology yields a significant correlation between large universe volume and high anisotropy. An analog of the model's chaotic classical behavior is seen in the break up of the universe wave function at large volume into fingers in the corners of the minisuperspace anisotropy potential.
In developing new receptor-site specific brain imaging agents labeled with I-123 for single photon emission computed tomography (SPECT), an analog of raclopride, 3-["1"2"5I]-iodo-N-[(1-ethyl-2-pyrrolidinyl)-methyl]-2-hydroxy-6-me-thoxy benzamide (IBZM), was prepared using a method similar to that reported for raclopride and its derivatives. (author).
With collaboration between chemistry, X-ray crystallography, and molecular modeling, we designed and synthesized a series of novel piperazine sulfonamide BACE1 inhibitors. Iterative exploration of the non-prime side and S2prime sub-pocket of the enzyme culminated in identification of an analog that potently lowers peripheral Ab40 in transgenic mice with a single subcutaneous dose.
We introduce a discrete multiplicative process as a generic model of competition. Players with different abilities successively join the game and compete for finite resources. Emergence of dominant players and evolutionary development occur as a phase transition. The competitive dynamics underlying this transition is understood from a formal analogy to statistical mechanics. The theory is applicable to bacterial competition, predicting novel population dynamics near criticality.
The authors study the nonuniformity of a-Si:H films obtained by the method of vacuum condensation, with the help of x-ray small-angle scattering (SLS) and transmission electron microscopy. Films of hydrogenated amorphous silicon are greatest interest, because the electronic properties of this material can be controlled by doping. As a result of the compensation of the ruptured bonds, and possibly, effects of melting, the properties of such films are analogous to those of singlecrystalline silicon. XLS enables a quantitative determination of the prameters of the regions of low electron density (RLD) in such objects.
Monoclonal antibodies (mAb) to ovine T-lymphocyte molecules SBU-T8 (Maddox, Mackay & Brandon, 1985), the cytotoxic T lymphocyte, human CD8 equivalent, and SBU-T6 (Mackay et al., 1985), the immature...Full Text Available
Log Gromov-Witten invariants have recently been defined separately by Gross and Siebert and Abramovich and Chen. This paper provides a dictionary between log geometry and holomorphic exploded manifolds in order to compare Gromov-Witten invariants defined using exploded manifolds or log schemes. The gluing formula for Gromov-Witten invariants of exploded manifolds suggests an approach to proving analogous gluing formulas for log Gromov-Witten invariants.
The aim of the paper is to define and study algebraic operations closely related to the group structure on the homotopy groups of topological spaces. These are certain many-place operations on the homotopy groups. The family of these operations induces an algebraic structure on the homotopy groups, which is called an A?-group structure by analogy with the A?-structures introduced by Stasheff.
The risks from radiation exposure during radiological diagnosis has usually been estimated in relation to genetic changes. Relevant information has been expressed as the genetically significant dose. In this paper we attempt to produce an analogous measure for evaluating the somatic risk in the form of a somatically significant dose index for radiological and CT examinations. It is shown that, for both types of examination, the two risk factors may be entirely different.
The risks from radiation exposure during radiological diagnosis has usually been estimated in relation to genetic changes. Relevant information has been expressed as the genetically significant dose. In this paper we attempt to produce an analogous measure for evaluating the somatic risk in the form of a somatically significant dose index for radiological and CT examinations. It is shown that, for both types of examination, the two risk factors may be entirely different. (orig.).
The excitation of compound-nucleus resonances in Y/sup 89/ and Zr/sup 90/ by proton bombardment at 4 to 5.5 Mev of Sr/sup 88/ and Y/sup 89/, respectively, is reported. Shell-model corfigurations were used to interpret the results. (R.E.U.)
A device for marking and searching for information on a magnetic carrier is described. In order to increase the noise immunity and reliability of the data recording and reading paths, the recording head is included between the amplifier of the clock pulses for the master oscillator and through the amplifier of the code pulses for the logical element unit. The reproduction head is connected through the code pulse shaper-amplifier with a switch which is connected with the display unit, and through another analogous clock pulse amplifier with a multivibrator.
We discuss three distinct topics of independent interest; one in enumerative combinatorics, one in symmetric function theory, and one in algebraic geometry. The topic in enumerative combinatorics concerns a q-analog of a generalization of the Eulerian polynomials, the one in symmetric function theory deals with a refinement of the chromatic symmetric functions of Stanley, and the one in algebraic geometry deals with Tymoczko's representation of the symmetric group on the cohomology of the regular semisimple Hessenberg variety of type A. Our purpose is to explore some remarkable connections between these topics.
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.
Positioning of release factor eRF1 toward adenines and the ribose-phosphate backbone of the UAAA stop signal in the ribosomal decoding site was studied using messenger RNA (mRNA) analogs containing...Full Text Available
We present a comparative study on the acoustic tunneling through artificial periodical composites, from phononic crystals to acoustic metamaterials. We find that the features of the acoustic tunneling are closely related with the origins of band gaps. In particular, the band gap associated with the negative effective material parameter in the metamaterial results in a better analog of the tunneling effect to the quantum system.
Suicide substrate β, γ-bidentate Rh(III)ATP (RhATP) was used to map the metal ion-binding site in yeast phosphoglycerate kinase (PGK). Cleavage of the RhATP-inactivated enzyme with...Full Text Available
The unparticle stuff which is described by the theory with notrivial IR fixed point is recently suggested to exist in our world by Georgi. We illustrate its physical effects in deep inelastic scattering process in this letter.
Physics traditionally serves mankind through its fundamental discoveries, which enrich our understanding of nature and the cosmos. While the basic driving force for physics research is intellectual curiosity and the search for understanding, the nation's support for physics is also motivated by strategic national goals, by the pride of world scientific leadership, by societal impact through symbiosis with other natural sciences, and through the stimulus of advanced technology provided by applications of physics. This Physics Survey volume looks outward from physics to report its profound impact on society and the economy through interactions at the interfaces with other natural sciences and through applications of physics to technology, medicine, and national defense.
"Physics in America is at a crossroads and in crisis, just as humanity stands on the verge of great discoveries about the nature of matter and the universe, a panel from the National Academy of sciences concludes in a new report."
BackgroundPrior research links optimism to physical health, but the strength of the association has not been systematically evaluated.PurposeFull Text Available
In this paper information about monograph construction is provided and some sample nomographs constructed by the author are included to encourage the use of these tools in operational health physics applications.
... with the symptoms of MS have MS. Diagnosis Physical examination and medical history are very important in diagnosing MS. Physical exams include a variety of tests to check ...
The Molecular Genetics and Carcinogenesis Section conducts studies using human epithelial cells to assess: activation of proto-oncogenes by chemical and physical carcinogens; inactivation and dysregulation of tumor suppressor genes by chemical and physical
"Physics in the United States is in a crisis that the country may lose the leadership in basic particle research in coming years, a report of the National Research Council warned." (1 page)
... mammography or on ultrasound but not found on physical examination, we consider them non-palpable or not ... lot of this. We send every patient for physical therapy, no matter what type of reconstruction we ...
Understanding the link between the Sun and climate is vital in the current incidence of global climate change, and 10Be in natural archives constitutes an excellent tracer for this purpose. As cosmic rays enter the atmosphere, cosmogenic isotopes like 10Be and 14C are formed. Variations in solar activity modulate the amount of incoming cosmic rays, and thereby cosmogenic isotope production. Atmospherically produced 10Be enters natural archives such as sediments and glaciers by wet and dry deposition within about a year of production. 10Be from natural archives therefore provides information on past solar activity, and because these archives also contain climate information, solar activity and climate can be linked. One remaining question is to what degree 10Be in natural archives reflects production, and to what extent the local and regional environment overprints the production signal. To explore this, 10Be was measured at annual resolution over the last 600 years in a Greenland ...
This paper presents the isothermal characteristics of methanol onto two specimens of activated carbons namely Maxsorb III and Tsurumi activated charcoal. Dubinin Raduskevich (D-R) equation is used to correlate the adsorption isotherms and to form the pressure-temperature-concentration diagram for both of the assorted pairs. Experimental results show that the maximum adsorption capacity of Maxsorb III/methanol pair is 1.76 times that of activated charcoal/methanol pair. Employing a time-independent mathematical model, the performance of adsorption cooling cycle using Maxsorb III/methanol and activated charcoal/methanol pairs has been studied and compared with that of three other types of carbon based adsorbent/methanol pairs. Theoretical calculations show the superiority of Maxsorb III/methanol pair for both of air-conditioning and ice-making applications. (author)
In order to perform the structural analysis and stress evaluation for frame structures in the nuclear power plants, ADAMS (AIJ Design Analysis and Modules System) has been developed by the addition of the following functions to the ICES-STRUDL system. 1. Load combination and stress evaluation on the basis of specifications for designing steel structure (issued by the Architecture Institute of Japan). 2. Combination of load and stress evaluation of piping support on the basis of the regulations of Ministry of International Trade and Industry. 3. Addition of other functions than that described above. ADAMS enables structural analysis and stress evaluation exactly and efficiently not only for a large scale structure such as the pipe whip protection structure installed inside of the primary containment vessel for many loading cases but also for a large number of structures such as piping support. This system can be applied not only to nuclear power plant but also other ...
The condensation reaction of furfural (F) on acetone (Ac) gives a high added value product, the 4-(2-furyl)-3-buten-2-one (FAc), used as aroma in alcohol free drinks, ice, candies, gelatines and other products of current life. This synthesis valorises the residues of sugar cane treatment since furfural is obtained by hydrolysis of sugar cane bagasse followed by vapor training extraction. In the face of numerous and complex reactions involved in this synthesis, it is very complicated to define the kinetic laws from exact stoichiometry. A solution allowing to cope the problem consists in identifying an appropriate stoichiometric model. It does not attempt to represent exactly all the reaction mechanisms, but proposes a mathematical support to integrate available knowledge on the transformati...
Viddi, F. A., Hucke-Gaete, R., Torres-Florez, J. P., and Ribeiro, S. 2010. Spatial and seasonal variability in cetacean distribution in the fjords of northern Patagonia, Chile. - ICES Journal of Marine Science, 67: 959-970. Compared with other Chilean coastal areas, little is known about the diversity and distribution of cetaceans in northern Patagonian fjords. Between December 2000 and November 2001, surveys on platforms of opportunity were undertaken in southern Chile to evaluate species richness and the spatial and seasonal distribution of cetaceans. Nine species were recorded, blue, humpback, and minke whales, Peales dolphin, Chilean dolphin, killer whale, false killer whale, bottlenose dolphin, and Cuviers beaked whale. The pattern of cetacean distribution displayed significant season...
In this report we present an update on the results from the Amanda-B10 detector which operated in 1997 at depths of 1500 to 2000 meters in the deep Antarctic ice. The goal of Amanda project is to search for extra-terrestrial neutrinos. As a precursor to such a search we have studied atmospheric neutrinos which act as a calibration source for the detector. The observation of atmospheric neutrinos at a rate consistent with Monte-Carlo predictions establishes Amanda-B10 as a neutrino telescope. The Amanda-B10 data has been searched for evidence of several classes of neutrinos and for magnetic monopoles. Searches for a diffuse high energy neutrino flux and for neutrinos in coincidence with gamma-ray bursts have been conducted. Preliminary data analyses show no excess of neutrinos has been found. (A.C.)
An approximate method of calculating the radius of thawing around an injection well is presented. The method is based on the assumption that for a cylindrical system the position of the phase interface in the Stefan problem can be approximated through two functions: one function determines the position of the melting-temperature isotherm in the problem without phase transitions and the second function does not depend on time. The adjusted heating time concept was used to describe the first function. The second function is a known analytical relationship and is expressed in terms of ice content, thermal properties of thawed/frozen formations, formation temperature and the temperature of the injected fluid. Simple approximate formulae are suggested to estimate the duration of the freezeback period. To verify the proposed formulae, the results of numerical solutions were used. An example which shows that the duration of the 'safety period' (free from freezing of water ...
The plug-in hybrid electric vehicle (PHEV) may offer a potential near term, low-carbon alternative to today's gasoline- and diesel-powered vehicles. A representative vehicle technology that runs on electricity in addition to conventional fuels was introduced into the MIT Emissions Prediction and Policy Analysis (EPPA) model as a perfect substitute for internal combustion engine (ICE-only) vehicles in two likely early-adopting markets, the United States and Japan. We investigate the effect of relative vehicle cost and all-electric range on the timing of PHEV market entry in the presence and absence of an advanced cellulosic biofuels technology and a strong (450ppm) economy-wide carbon constraint. Vehicle cost could be a significant barrier to PHEV entry unless fairly aggressive goals for re...
The aim of this study is to evaluate the specificities of the irradiation of drugs in frozen aqueous solution. The structures of the degradation products were determined to gain insight into the radiolysis mechanisms occurring in frozen aqueous solutions. Metoclopramide hydrochloride and metoprolol tartrate were chosen as models. The frozen solutions were irradiated at dry ice temperature by high energy electrons at various doses. The drug purity (chemical potency) and the radiolysis products were quantified by HPLC-DAD. Characterization of the degradation products was performed by LC-APCI-MS-MS. The structures of the radiolysis products detected in irradiated frozen aqueous solutions were compared to those detected in solid-state and aqueous solutions (previous studies). For both metoclop...
This two-tomes book brings together the 108 presentations given at the first conference of the international institute of refrigeration (IIF/IIR) about air conditioning in high rise office buildings. The main themes are: general design and control systems, including split systems, radiant panels, fluctuating and gravity ventilation etc..; energy consumption, optimization and heat recovery; cold storage for peak shaving, including ice slurry circulation; indoor air quality; fire and smokes protection, protection against chimney effects and lighting spots; use of fuzzy logic and of neural networks. It includes also a description of the high rise building situation and works in progress in China, Japan and in some other countries. (J.S.)
There are alarming scenarios that state that global heating caused by anthropogenic gaseous emissions will melt the ice caps of Greenland and the Antarctic. This would cause flooding of coastal regions on a global scale. The floods are expected already in the next century, but there are no realistic assessments of the extent of the danger. (orig.) [Deutsch] Alarmierenden Szenarien zufolge koennten durch eine globale Erwaermung, die der Mensch mit dem Ausstoss von Treibhausgasen in die Atmosphaere verursacht, die Eiskappen auf der Antarktis und Groenland abschmelzen. Schon im kommenden Jahrhundert wuerden dadurch weite kuestennahe Gebiete ueberflutet. Noch aber laesst sich schwer abschaetzen, wie real die Gefahr ist. (orig.)
This paper provides both a detailed history of environmental change in the Sierra Nevada over the past 1,800?years and evidence for climate teleconnections between the Sierra Nevada and Greenland during the late Holocene. A review of Greenland ice core data suggests that the magnitudes of abrupt changes in temperature and precipitation increased beginning c. 3,700 and 3,000?years ago, respectively. Precipitation increased abruptly 1,300?years ago. Comparing paleotemperature data from Cirque Peak, CA with paleoprecipitation data from Pyramid Lake, NV suggests that hot temperatures occurred at the beginnings of most severe droughts in the Sierra Nevada over the past 1,800?years. Severe fires and erosion also occurred at Coburn Lake, CA at the beginning of all severe droughts in the Sierra Ne...
This handbook is a unique compendium of knowledge on all aspects of the physics of liquid crystals. In over 500 pages it provides detailed information on the physical properties of liquid crystals as well as the recent theories and results on phase transitions, defects and textures of different types of liquid crystals. An in-depth understanding of the physical fundamentals is a prerequisite for everyone working in the field of liquid crystal research. With this book the experts as well as graduate students entering the field get all the information they need.
The CMS Physics Analysis Toolkit (PAT) is presented. The PAT is a high-level analysis layer enabling the development of common analysis efforts across and within Physics Analysis Groups. It aims at fulfilling the needs of most CMS analyses, providing both ease-of-use for the beginner and flexibility for the advanced user. The main PAT concepts are described in detail and some examples from physics analyses are given.
Inspired by the work of Feynman, Deutsch, We formally propose the theory of physical computability and accordingly, the physical complexity theory. To achieve this, a framework that can evaluate almost all forms of computation using various physical mechanisms is discussed. Here, we focus on using it to review the theory of Quantum Computation. As a preliminary study on more general problems, some examples of other physical mechanism are also given in this paper.
"Network Physics, the only provider of physics-based network management products, today announced an additional venture round of $6 million in funding, as well as the addition of David Jones as president and CEO and Tom Dunn as vice president of sales and business development" (1 page).
This report describes the research conducted in the High Energy Physics Division of Argonne National Laboratory during the period of July 1, 1992--December 30, 1992. Topics covered here include experimental and theoretical particle physics, advanced accelerator physics, detector development, and experimental facilities research. Lists of division publications and colloquia are included.
This report describes the research conducted in the High Energy Physics Division of Argonne National Laboratory during the period of January 1, 1993--June 30, 1993. Topics covered here include experimental and theoretical particle physics, advanced accelerator physics, detector development, and experimental facilities research. Lists of division publications and colloquia are included.
This spring, Newfoundland will send off a floating production, storage and offloading (FPSO) vessel to the offshore Terra Nova field. The Terra Nova will proceed southeast through Bull Arm, then northeast out of Trinity Bay, then heads southeast to the Jeanne d'Arc Basin on the Grand Banks. The Terra Nova is expected to produce 115,000 barrels of oil per day for six years, when it reaches full capacity. The consortium, headed by Petro-Canada as senior ownership partner and operator, built an environment protection program into every aspect of the project. Some of the features of the environment protection program include glory holes excavated on the ocean floor for the protection of production equipment from icebergs, to a flare stack on the platform, which has four legs to provide stability in rough seas. The FPSO was designed to withstand sea ice, icebergs, and severe winter storms. Flow lines are also protected, and in the event that a line is damaged, ...
Ewing's sarcoma is the most common malignant bone tumour occurring in children and adolescents and exists in two different clinico pathological entities: osseous Ewing's sarcoma (OES) and extraosseous Ewing's sarcoma (EES). Five cases of primary epidural EES are described, which presented with non-specific symptoms leading to a long diagnostic delay. The median age at diagnosis was 22 years (range 13-36 years). The median diagnostic delay was 3 months. All patients had one or more neurological deficits. All underwent surgical exploration with a laminectomy and partial resection followed by adjuvant radiotherapy to a dose of 46-50 Gy and chemotherapy with VAC (vincristine, adriamycin and cyclophosphamide) alternating with ICE (ifosphamide, cisplatin and etoposide) for at least six cycles. The mean follow-up period is 21.2 months (range 11-32 months). Four of the five patients achieved a complete remission and are disease free at the time of writing this report. Two ...
Tritium is produced in large quantities at heavy water nuclear power reactors via the neutron activation reaction "2H(n,#gamma#)"3H. At Wolsung nuclear power plant which has a CANDU reactor, the tritium concentrations in coolant and in moderator systems are 1.5 Ci/Kg-D_2O and 35 Ci/kg-D_2O, respectively, after 12 years of operation. The airborne tritium concentration in main access area is normally less than 5 MPCa except short-term peaks. The average tritium concentrations in main access controlled areas are normally less than 100 MPCa. Tritium is mainly present in the air of workplace of CANDU reactors as a tritiated water vapour. Airborne tritiated water vapour enters the workers body via inhalation and absorption through skin and can result in a significant dose. The occupational doses from tritium at Wolsung NPP have been maintained below 1 man-Sv per year so far. The tritium contribution to the total plant man-Sv changes between 30 percent and 50 percent. For the mitigation of ...
In 2009 the European Space Agency satellite mission GOCE (Gravity Field and Steady-State Ocean Circulation Explorer) was launched. Its objectives are the precise and detailed determination of the Earth's gravity field and geoid. Its core instrument, a three axis gravitational gradiometer, measures the gravity gradient components V xx , V yy , V zz and V xz (second-order derivatives of the gravity potential V) with high precision and V xy , V yz with low precision, all in the instrument reference frame. The long wavelength gravity field is recovered from the orbit, measured by GPS (Global Positioning System). Characteristic elements of the mission are precise star tracking, a Sun-synchronous and very low (260 km) orbit, angular control by magnetic torquing and an extremely stiff and thermally stable instrument environment. GOCE is complementary to GRACE (Gravity Recovery and Climate Experiment), another satellite gravity mission, launched in 2002. While GRACE is designed to ...
The generation of thermal energy is the great importance for the agribusiness of dairy industry to conservation the quality of milk, taking into account that the electricity is the main source currently used for the thermal energy input. The small agribusiness dairy industry currently practiced in Brazil faces several problems related to the cost of electricity and the distance of rural properties of networks of power. In the current scenario of Brazilian dairy production, there is need for the generation of cold for the milk cooling, and also the heat for the production of hot water around 50 deg C to 60 deg C and also for cleaning of equipment used for milk production and processing. The main objective of this study is the modeling and simulation of integrated recovery process of solid waste, effluents and bioconversion. The specific project objectives are: comparison study of options and technological routes of low cost material for power generation using conventional and innovative ...
This book summarizes the research that has been conducted in Canada over the past five years on the issue of climate change impacts on key sectors such as water resources, agriculture, forestry, fisheries, coastal zones, transportation, and human health and well-being. The book refers to the growing evidence that climate change is occurring. The Intergovernmental Panel on Climate Change (IPCC) believes that these changes have already contributed to increases in annual precipitation, cloud cover and extreme temperatures over the last 50 years. It suggests that it in order to develop an effective strategy for adaptation, it is necessary to understand the vulnerability of each sector to climate change in terms of the nature of climate change, the climatic sensitivity of the region being considered, and the capacity to adapt to the changes. Adaptation will require a reduction in greenhouse gas emissions in order to lower the rate of climate change. Problems associated with water resources ...
The 'elementary' particle physics began in 1935, when Hideki Yukawa published his pioneering pi-meson theory, and the problem of strong interaction was finally solved 40 years later by the establishment of the Standard Model. The composite models of hadrons by the Sakata school and Sin-itiro Tomonaga's renormalization theory for quantum electrodynamics played essential roles for finding this beautiful solution. It is really surprising that it took only 40 years to solve such desperately difficult problem. The 'elementary' particle physics then split into two new fields, quark-hadron physics' and 'unified (ultimate) theory of particle physics', which are now 30 years old already. (author)
We investigate the influence of lunar-like satellites on the infrared orbital light curves of Earth-analog extra-solar planets. Such light curves will be obtained by NASA's Terrestrial Planet Finder (TPF) and ESA's Darwin missions as a consequence of repeat observations to confirm the companion status of a putative planet. We use an energy balance model to calculate disk-averaged infrared (bolometric) fluxes from planet-satellite systems over a full orbital period (one year). The satellites are assumed to lack an atmosphere, have a low thermal inertia like that of the Moon and span a range of plausible radii. The planets are assumed to have thermal and orbital properties that mimic those of the Earth while their obliquities and orbital longitudes of inferior conjunction remain free parameters. Even if the gross thermal properties of the planet can be independently constrained (e.g. via spectroscopy or visible-wavelength detection of specular glint from a surface ...
Although the mechanism is unknown, Calculus Bovis and its active components, cholic acid analogs (CAAs), have been used in China to treat a wide range of diseases. Based on the previous finding that the potency of CAA is strongly dependent on the intrinsic surface activity, this paper aimed to investigate the role of the plasma membrane in the pharmacological activity of CAAs. First, CAAs (0.1 mM) caused a surface activity-dependent depression on ATPase activity in the cell membrane extract, but it had no effects on other cellular extracts, suggesting an indispensable role of the membrane environment for pharmacological activity. Second, CAAs lowered the membrane fluidity of cultured Caco-2 cells with the same rank-order of potency sequence. Third, the hypothesis that any functional protein located on the membrane is influenced by changes in cellular membrane fluidity was supported by: ileal contraction that was induced by acetylcholine and mediated by the ...
The Maxwell algebra is a noncentral extension of the Poincare algebra, in which the momentum generators no longer commute, but satisfy [P?,P?]=Z??. The charges Z?? commute with the momenta, and transform tensorially under the action of the angular momentum generators. If one constructs an action for a massive particle, invariant under these symmetries, one finds that it satisfies the equations of motion of a charged particle interacting with a constant electromagnetic field via the Lorentz force. In this paper, we explore the analogous constructions where one starts instead with the ISim subalgebra of Poincare, this being the symmetry algebra of very special relativity. It admits an analogous noncentral extension, and we find that a particle action invariant under this Maxwell-Sim algebra again describes a particle subject to the ordinary Lorentz force. One can also deform the ISim algebra to DISimb, where b is a nontrivial dimensionless ...
We have measured the K-shell ionization probability Psub(K) across the isobaric analog resonances in the elastic channel of the reactions /sup 88/Sr(p, p/sub 0/)/sup 88/Sr at 5.06 MeV and /sup 86/Sr(p, p/sub 0/)/sup 86/Sr at 6.02 MeV. The dependence of Psub(K) on the beam energy for two scattering angles 90/sup 0/ and 155/sup 0/ is analysed in the framework of the theory developed by Anholt et al. taking into account the effect of compound-nucleus scattering. A compound elastic cross section (dsigma/d..cap omega..)sub(CE)=40+-10 mb/se at the peak of the resonance is deduced in the reaction /sup 88/Sr+p at 5.06 MeV, while the experimental results agree with a negligible value of (dsigma/d..cap omega..)sub(CE) for the resonance in /sup 86/Sr+p at 6.02 MeV.
We have measured the K-shell ionization probability Psub(K) across the isobaric analog resonances in the elastic channel of the reactions "8"8Sr(p, p_0)"8"8Sr at 5.06 MeV and "8"6Sr(p, p_0)"8"6Sr at 6.02 MeV. The dependence of Psub(K) on the beam energy for two scattering angles 90"0 and 155"0 is analysed in the framework of the theory developed by Anholt et al. taking into account the effect of compound-nucleus scattering. A compound elastic cross section (dsigma/d#OMEGA#)sub(CE)=40+-10 mb/se at the peak of the resonance is deduced in the reaction "8"8Sr+p at 5.06 MeV, while the experimental results agree with a negligible value of (dsigma/d#OMEGA#)sub(CE) for the resonance in "8"6Sr+p at 6.02 MeV. (orig.).
Postresection villus hyperplasia is a major compensatory mechanism in the short-bowel patient. Substances capable of augmenting postresection mucosal hyperplasia could have therapeutic implications. Human growth hormone (hGH) and human growth hormone releasing factor (hGHRF) stimulate growth of the gastrointestinal tract; however, the diabetogenic actions of growth hormone limit its usefulness in clinical practice. Plerocercoid larvae of the tapeworm Spirometra mansonoides produce an analog of hGH void of diabetogenic side effects. We assessed effects of plerocercoid growth factor (PGF) on mucosal adaptation following 70% proximal jejunoileal resection in young rats. Mucosal weight, DNA, protein, and total sucrase activity per centimeter of bowel were increased in resected PGF-treated animals compared to resected controls. We conclude PGF augments intrinsic postresection mucosal hyperplasia following extensive intestinal resection. PMID:3665682
For many years, the Lower Cretaceous Sunniland oil-producing fields have been interpreted as reef deposits. Petrologic evidence from cores from field and wildcat wells strongly indicates on the basis of faunal composition and character, that the fields are producing from moundlike shoals. These shoals are considered to have been deposited in a mudflat environment similar to that of present-day Florida Bay. This present-day Florida Bay analog is used to determine the various environmental subzones and controls on the deposition of the Sunniland Formation. This concept of using a model together with a modern analog can be a powerful tool in the exploration of stratigraphic traps. A petrologic and petrophysical study of the Sunniland Formation in the wells that have been drilled in the Florida Bay and Keys areas was made to extend the model and its application throughout the South Florida basin. The evaluation of these wells has produced new ...
The effect of UV radiation in the wavelength region 230 nm to 302 nm on the ability of an irradiated mammalian cell to reactivate UV-irradiated mammalian virus was tested. An action spectrum for radiation enhanced reactivation (RER) is presented. The shape of the action spectrum points to a combined nucleic acid-protein target for UV radiation effects on this cellular parameter. An analysis of the results of others involving the biochemical and photobiological events involved in RER does not allow us to distinguish which macromolecule is the major contributor to this effect. Studies involving an analogous phenomenon in bacteris (Weigle reactivation) imply that RER and WR amy involve similar mechanisms. (author).
We searched for signs of an instability on the interface between the two phases of a binary-liquid mixture, isobutyric acid and water, after the mixture was quenched further into the two-phase region. Such an instability would be the liquid-liquid analog of the Mullins-Sekerka instability seen in quenched alloys. Never is any dramatic growth observed, but under conditions of small dimensionless quench depth (theta<1.5 x 10/sup -3/), the intensity of light scattered from the interface grows for small values of the momentum transfer k.
ABS>A horizontal steam generator design for the SM-2 was lysis to determine the per formance of such a steam generator under steady state operating conditions and during load transients, The configuration for this design is a two- drum unit consisting of a heat exchanger unit and separator drum interconnected by integral riser and downcomer. An analog computer was used to analyze the steam generator behavior Wring load transients. The effect of various design changes on the response of the steam generator to step chages in load was determined. The horizontal steam generator design was compared to the existing vertical steam generator design for weight, size, price, and performance. (auth)
By the methods of microstructural and electron-microscopic analyses by the tension test and impact test studied is the effect of quenching conditions on structure and mechanical properties of the TS6 titanium-#beta# alloy. It is shown that low temperature quenching from 700 deg C, recommended earlier for analogous VT15 titanium alloy, leads to appearence of intercrystalline fracture and to sharp decrease of impact strength of the TS6 alloy. Established are optimum conditions for quenching of half-finished products and articles of the TS6 alloy depending on their subsequent working or operation.
The paper develops a new class of financial market models. These models are based on generalized telegraph processes: Markov random flows with alternating velocities and jumps occurring when the velocities are switching. While such markets may admit an arbitrage opportunity, the model under consideration is arbitrage-free and complete if directions of jumps in stock prices are in a certain correspondence with their velocity and interest rate behaviour. An analog of the Black-Scholes fundamental differential equation is derived, but, in contrast with the Black-Scholes model, this equation is hyperbolic. Explicit formulas for prices of European options are obtained using perfect and quantile hedging.
The present paper further characterizes the cholinergic properties of acetylselenonium choline (ASeCh, (CH3)2Se+CH2CH2OCOCH3). The data demonstrate that ASeCh possesses muscarinic receptor agonist properties as evidenced by vasodepressor and smooth muscle contractile activities which are enhanced by physostigmine and antagonized by atropine. ASeCh also possessed nicotinic agonist activity on frog rectus abdominis tissue which was potentiated by physostigmine, and blocked by d-tubocurarine. The relative potencies of ASeCh ranged from approximately 1% to approximately 6% of the potency of acetylcholine in the three types of preparations examined. PMID:1435078
A primary goal of noninvasive studies of human vision is to identify and characterize multiple visual areas in the human brain analogous to those identified in studies of nonhuman primates. By combining functional MEG measurements with images of individual anatomy derived from MRI, the authors hope to determine the location and arrangement of multiple visual areas in human cortex and to probe their functional significance. The authors have identified several different visual areas thus far which appear to be topographically organized. This paper focuses on the retinotopic characterization of the primary visual area (V1) in humans.
Since the PWR plants in Japan have been operated more than 30 years, main instrumentation control equipment of analog systems has been renewed to digital control systems. Renewal works had to be done in short period within periodical inspection term and for several facilities. The Mitsubishi LTD group had been provided with these market needs by its digital control system (MELTAC-NplusR 3) applicable to main instrumentation control equipment for primary and secondary systems and had already finished the renewal for practical plants. (T. Tanaka)
We show that in the Landau gauge of the SU(2) Yang-Mills theory the residual global symmetry supports existence of the topological vortices which resemble disclination defects in the nematic liquid crystals and the Alice (half-quantum) vortices in the superfluid heluim 3 in the A-phase. The theory also possesses half-integer and integer charged monopoles which are analogous to the point-like defects in the nematic crystal and in the liquid helium. We argue that the deconfinement phase transition in the Yang-Mills theory in the Landau gauge is associated with the proliferation of these vortices and/or monopoles. The disorder caused by these defects is suggested to be responsible for the confinement of quarks in the low-temperature phase.
Hexane extract of licorice (Glycyrrhiza glabra L.) roots was obtained and investigated. Hydrocarbons, sterol ethers, triacylglycerides, free fatty acids, and free sterols were identified. The extract contains 70% neutral and 30% polar lipids. It is established that the lipid fraction of licorice roots is more effective than the analogous fraction of rosehip oil in stimulating the reparative regeneration of skin. In addition, this fraction also exhibits pronounced antiinflammatory and antiulcer effects, while being virtually nontoxic. Based on these results, the lipid fraction of licorice roots can be recommended as a parent substance for creating effective preparations in various medicinal forms.
In the context of the shock-initiation problem, we study analytically the first effects of chemistry, treating a small chemical heat release as a perturbation on an inert flow. Specifically, we study the initial transient in plane-shock initiation in a dilute explosive, where the chemical energy is small relative to the mechanical-thermal energy. The vehicle for the study is the mathematical analog for reactive flow. The solution resembles a double refraction: to first order, the pressure or density is a superposition of two forward-going waves, both originating at the rear boundary, and carrying the same function, but running at different velocities. Surprisingly, this first-order solution is independent of the sensitivity of the reaction rate to the state, which appears only at second order.
The gravitational radiation produced by the big bang is calculated in order to provide a condition for the unification of the gravitational and electromagnetic forces. By analogy with electromagnetic radiation and under the assumption that gravity is also quantized, it is shown that matter would have decoupled from gravitational radiation at a time of approximately 10 to the -43rd sec and would have dominated it at 10 to the -17th sec. Furthermore, the theory predicts a background gravitational radiation temperature of 0.003 K which peaks at a wavelength of about 1 m, which may be detected by the comparison of the synchronization of clocks at increasing distances.
Until April 2007 the Major Atmospheric Gamma ray Imaging Cherenkov (MAGIC) telescope used a 300 MSamples/s flash analog-to-digital converter (FADC) system to sample the shaped photomultiplier tube (PMT) signals produced by the captured Cherenkov photons of air showers. Different algorithms to reconstruct the signal from the read-out samples (extractors) have been implemented and are described and compared. Criteria based on the obtained charge and time resolution/bias are defined and used to judge the different extractors, by applying them to calibration, cosmic and pedestal signals. The achievable charge and time resolution have been derived as functions of the number of incident photo-electrons.
This book presents in simple terms the basis of molecular genetics and how it is used to obtain an understanding of the human genome. The author's central focus is the transistion of genetics from statistics to experimental manipulations, and he offers analogies that help readers visualize the genome, thereby avoiding conventional scientific presentations. He illustrates how genetics is used in scientific laboratories, in courtrooms, and in hospitals. Little is presented about the complex social and ethical issues raised by the Human Genome project.
A theoretical analysis is presented for the method of determining the concentration distribution of admixtures in zone melting and in the study of diffusion in melts. Continuous mode X-ray fluorescence analysis is considered. The convolution integral interpreting the analog output of the ratemeter was solved applying the mathematical apparatus of Z transformation. The feasibility of the method is tested on an example of the determination of tin distribution in tungsten. With respect to the statistical error (#delta#<1.5%), the maximum integration constant (100 s) and a very slow sample feed (0.025 mm/s) were used. The calculated transfer function reflects the total transfer function of the ratemeter and the recorder used. (M.D.).
In several recent papers on entanglement in relativistic quantum systems and relativistic Bell's inequalities, relativistic Bell-type two-particle states have been constructed in analogy to nonrelativistic states. These constructions do not have the form suggested by relativistic invariance of the dynamics. Two relativistic formulations of Bell-type states are shown for massive particles, one using the standard Wigner spin basis and one using the helicity basis. The construction hinges on the use of Clebsch-Gordan coefficients of the Poincare group to reduce the direct product of two unitary irreducible representations (UIRs) into a direct sum of UIRs.
Energy and angular double-differential cross-section (DDX) data of fragment production reactions by neutrons or protons are very scarce due to experimental difficulties of fragment detection. We adopted a Bragg curve spectrometer (BCS), which is a gridded-ionization chamber that can identify fragments on the basis of the Bragg peak value. We have been developing the BCS for neutron and proton-induced reactions applying the digital waveform analysis technique to obtain better ability of particle discrimination than the analog electronic circuit. (T. Tanaka)
(methine-{sup 3}H)1,1-Di-(4-chlorophenyl)-2,2,2-trichloroethane ((methine-{sup 3}H)DDT) and its di-(4-nitrophenyl) analog, both of high purity with a moderately high specific activity were prepared. Chloro-benzene was condensed with (1-{sup 3}H)1-(4-chlorophenyl)-2,2,2-trichloro-ethanol, which has been synthesized by sodium boro({sup 3}H)hydride reduction of 4-chlorophenyl trichloromethyl ketone. The purified ({sup 3}H)DDT had a specific activity of 0.77 Ci/mmol (28.49 GBq/mmol). (methine-{sup 3}H)1,1-Diphenyl-2,2,2-trichloroethane was similarly synthesized and was nitrated to give (methine-{sup 3}H)1,1-di-(4-nitrophenyl)-2,2,2-trichloro-ethane of 1.63 Ci/mmol (60.31 GBq/mmol). Dehydrochlorination with housefly enzyme (glutathione-dependent DDT dehydrochlorinase) showed a remarkable isotope effect. For DDT, the observed tritium isotope effect on V{sub max}/K{sub m} was 11.51{plus minus}0.52. For the nitro-analog, the value was 11.3{plus ...
Photoaffinity labeling analogs of the adenylate cyclase activator forskolin (PF) have been synthesized, purified and tested for their effect on preparations of membrane-bound, Lubrol solubilized and forskolin affinity-purified adenylate cyclase (AC). All analogs of forskolin significantly activated AC. However, in the presence of 0.1 to 0.3 microM forskolin, the less active forskolin photoaffinity probes at 100 microM caused inhibition. This inhibition was dose-dependent for PF, suggesting that PF may complete with F for the same binding site(s). After cross-linking (125I)PF-M to either membrane or Lubrol-solubilized AC preparations by photolysis, a radiolabeled 100-110 kDa protein band was observed after autoradiography following SDS-PAGE. F at 100 microM blocked the photoradiolabeling of this protein. Radioiodination of forskolin-affinity purified AC showed several protein bands on autoradiogram, however, only one band (Mr = 100-110 kDa) was ...
Ethylene is a plant hormone that elicits a wide variety of responses in plant tissue. Among these responses are the hastening of abscission, ripening and senescence. In 1979 it was discovered that 1-amino-1-cyclopropane carboxylic acid is the immediate biosynthetic precursor to ethylene. Given the obvious economic significance of ethylene production the authors concentrated their studies on the conversion of ACC to ethylene. They delved into mechanistic aspects of ACC oxidation and they studied potential inhibitors of ethylene forming enzyme (EFE). They synthesized various analogs of ACC and found that EFE shows good stereodiscrimination among alkyl substituted ACC analogs with the 1R, 2S stereoisomer being processed nine times faster than the 1S, 2R isomer in the MeACC series. They also synthesized 2-cyclopropyl ACC which is a good competitive inhibitor of EFE. This compound also causes time dependent loss of EFE activity leading us to believe ...
Derivatives of angiotensin with a sarcosine substitution at the carboxy terminus and an aliphatic amino acid substitution at the amino terminus have been shown to be competitive ligands for the angiotensin receptor. Scatchard plots derived from saturation isotherm data in bovine adrenal particulates consistently demonstrate three to five times the number of binding sites for "1"2"5I-Sarl,Ile8-AII ("1"2"5I-SI-AII) than for "1"2"5I-AII in experiments in which the two ligands are run side-by-side. A significant difference between "1"2"5I-AII and "1"2"5I-SI-AII binding to detergent solubilized angiotensin receptors was observed. Of the "1"2"5I-AII binding sites, about 85-90% were recovered upon solubilization. In contrast, the recovery of "1"2"5I-SI-AII binding sites was only 4-5%. To determine whether binding sites labeled in the soluble state represent biologically significant AII receptors, they examined the ability of selected angiotensin analogs to inhibit ...
Hydrocarbon recovery efficiency is controlled by reservoir heterogeneities resulting from geometric arrangements of strata, or {open_quotes}stratal architecture{close_quotes}. Traditional reservoir characterization relates depositional systems to stratal architecture. High-resolution sequence stratigraphy of outcrop analogs provides a chronostratigraphic framework for evaluating accommodation conditions of depositional systems. Key stratigraphic surfaces and/or correlative strata define a hierarchy of chronostratigraphic units of different periodicities. The Upper Cretaceous Ferron Sandstone, an analog to high accommodation and sediment supply fluvial-deltaic reservoirs, comprises an intermediate-term stratigraphic sequence consisting of seven short-term stratigraphic cycles. Each short-term stratigraphic cycle contains fluvial- to storm-dominated shallow-marine deposits laterally replaced by distributary channel deposits. The Lower Cretaceous ...
The Pulsed Lepton Source (PLS) project opens some exciting possibilities for muon and neutrino physics . The PLS would use the 0.25 4s proton pulses from the upgraded Proton Storage Ring (PSR) at LAMPF to create short, intense bursts of muons and neutrinos. The neutrino beam would be used for a few fundamentally important weak interaction physics experiments. The muon beams would find a wide variety of applications in both fundamental and applied'' muon physics areas. After a brief discussion of the physical layouts of the PSR and the proposed PLS in Sec. 2 and muon area in Sec. 3, we note some of the muon physics experiments and areas that could advantageously be addressed at the PLS in Secs. 4 and 5, and conclude in Sec. 6.
The New Yorker Richard Feynman, well known to all physicists for his diagrams. Eleven vivid posters have recently been hung along the Theoretical Physics corridor on the first floor of Building 53. They tell the story of a century of physics, between 1900 and the end of the nineteen-nineties, the century that gave us atomic and quantum physics and the great breakthroughs that have rocked our understanding of the world and the universe. The posters are a gift from the American Physical Society to the CERN Library. As they were designed for high school and university book collections in the US, they necessarily have a somewhat American view of the history of science. But it is still instructive to revisit contemporary physics through its great figures, such as Marie Curie, Stephen Hawking, and Richard Feynman, not to mention Albert Einstein and many others. Why not take the time for a ...
Utah oil fields have produced over 1.2 billion barrels (191 million m{sup 3}). However, the 13.7 million barrels (2.2 million m{sup 3}) of production in 2002 was the lowest level in over 40 years and continued the steady decline that began in the mid-1980s. The Utah Geological Survey believes this trend can be reversed by providing play portfolios for the major oil-producing provinces (Paradox Basin, Uinta Basin, and thrust belt) in Utah and adjacent areas in Colorado and Wyoming. Oil plays are geographic areas with petroleum potential caused by favorable combinations of source rock, migration paths, reservoir rock characteristics, and other factors. The play portfolios will include: descriptions and maps of the major oil plays by reservoir; production and reservoir data; case-study field evaluations; summaries of the state-of-the-art drilling, completion, and secondary/tertiary techniques for each play; locations of major oil pipelines; descriptions of reservoir outcrop ...
It is shown that the interaction of a class of positive energy tachyons decreases the area of the horizon of the T-S, delta = 3 metric even in the case of a reversible transformation (Msub(ir) = constant). This is a violation of the second law of black hole physics.
It is shown that the interaction of a class of positive energy tachyons decreases the area of the horizon of the T-S, delta = 3 metric even in the case of a reversible transformation (Msub(ir) = constant). This is a violation of the second law of black hole physics. (author).
This talk summarizes recent progress in top quark physics studies for high energy linear electron-positron colliders as presented at the LCWS2000 Workshop at Fermilab. New results were presented for top pair production at threshold and in the continuum, as well as for top production at #gamma##gamma# colliders.
The purpose of this study was to examine relationships between weather and outdoor physical activity (PA). An online weather source was used to obtain daily max temperature [DMT], precipitation, and...Full Text Available
Shoulder pain is a common orthopedic condition seen by physical therapists, with many potential contributing factors and proposed treatments. Although manual physical therapy interventions for the cervicothoracic...Full Text Available
It is shown that the usual proof of the second law of black hole physics breaks down if there are tachyons present in the vicinity of a black hole. Explicit cases are discussed where a tachyon of positive energy falling into the Kerr singularity actually decreases the area of the Kerr black hole. (author).
A review of recent work in nuclear physics is presented. The paper gives a broad discussion of research goals in nuclear structure, quark-gluon degrees of freedom, quark-gluon plasma, symmetries, and rare decays. (DWL)
The objectives of this research are: (1) to assess selected formulation-relevant physical properties of several commercial Feverfew extracts, including flowability, hygroscopicity, compressibility and...Full Text Available
This article focuses on results of the systematic review from the Guide for Useful Interventions for Activity in Latin America project related to school-based...Full Text Available
Quantum computers hold great promises for the future of computation. In this paper, this new kind of computing device is presented, together with a short survey of the status of research in this field. The principal algorithms are introduced, with an emphasis on the applications of quantum computing to physics. Experimental implementations are also briefly discussed.
AbstractQuantities and types of ceramides and their relationships to physical properties of the horn covering the claws of clinically normal cows and cows with subclinical laminitis were...Full Text Available
I review the physic prospects for high energy photon photon colliders, emphasizing results presented at the LBL Gamma Gamma Collider Workshop. Advantages and difficulties are reported for studies of QCD, the electroweak gauge sector, supersymmetry, and electroweak symmetry breaking.
I review the physics prospects for high energy photon photon colliders, emphasizing results presented at the LBL Gamma Gamma Collider Workshop. Advantages and difficulties are reported for studies of QCD, the electroweak gauge sector, supersymmetry, and electroweak symmetry breaking. ((orig.)).
I review the physic prospects for high energy photon photon colliders, emphasizing results presented at the LBL Gamma Gamma Collider Workshop. Advantages and difficulties are reported for studies of QCD, the electroweak gauge sector, supersymmetry, and electroweak symmetry breaking.
I review the physics prospects for high energy photon photon colliders, emphasizing results presented at the LBL Gamma Gamma Collider Workshop. Advantages and difficulties are reported for studies of QCD, the electroweak gauge sector, supersymmetry, and electroweak symmetry breaking. ((orig.)).
ObjectiveTo evaluate the association of physical activity with left ventricular structure and function in the general population in a community setting.Full Text Available
A critical problem for reliable implementation of regional discrimination is incomplete understanding of how regional seismic signals depend on physical characteristics of the source and propagation path to the recording station. This research is directed...
Physical activity is associated with reduced risk of several age-related diseases as well as with increased longevity in both rodents and humans. Though these associations are well established, evidence...Full Text Available
In order to understand how matter 15 billion years ago in the form of quarks, gluons and leptons at a temperature of 2 (times) 10(sup 12) (degrees)K evolved to become today's Universe, the goal of relativistic and ultra-relativistic heavy ion physics is t...
The following topics are dealt with: Detectors at COSY, major physics results at COSY, physics at external facilities, theoretical investigations, COSY operation and developments, preparations for FAIR, technical developments. (HSI)
Prof. Kodi Husimi was the director of the Institute of Plasma Physics of Nagoya University during 12 years from the beginning of the institute establishment in 1961. His main contribution on promotion of plasma physics and fusion research at the Institute is summarized. (author)
The objective of this work was to evaluate the physical properties and in vivo circulation of chitosan (CH)-coated liposomes of mitoxantrone (MTO). Changes in particle size and zeta...Full Text Available
AbstractEffects of dietary biotin supplementation on serum biotin levels and physical properties of sole horn of 40 Holstein cows were evaluated. The mean serum biotin level in biotin-supplemented...Full Text Available
The effects of ammonia and hydrogen sulfide on the physical and biochemical properties of the claw horn of Holstein cows were evaluated. Significant (P < 0.05, 0.01) decreases...Full Text Available
Multiple disease-specific systematic reviews on the effectiveness of physical therapy intervention for shoulder dysfunction have been inconclusive. To date, there have been two systematic reviews that...Full Text Available
... materials science and engineering, condensed-matter or materials physics, solid-state or materials ... include materials theory, condensed-matter and materials physics, solid-state and materials ...
BackgroundPhysical inactivity is related to many morbidities but the evidence of its link with depression in adolescents needs further investigation in view of the existing conflicting...Full Text Available
... and at that point she had already failed physical therapy, which someone else had prescribed, and so ... MRI, we may try a brief course of physical therapy to see if they feel better, but ...
Clinical features and treatment outcome were compared in depressed outpatients with and without a history of emotional and physical abuse (EPA), including childhood maltreatment. Patients were...Full Text Available
Initial results obtained with a Monte Carlo computer program designed to link initial physical events in irradiated liquid water with subsequent chemical and biological events are presented. 10 refs., 4 figs., 3 tabs.
BackgroundPhysical performance measures are widely used to assess physical function, providing information about physiological and biomechanical aspects of motor performance. However...Full Text Available
Part one of this study investigated the effect of aging on social-cognitive characteristics related to physical activity (PA) among adults in the baseline phase of a health promotion...Full Text Available
This commentary adds effect sizes to the recently published systematic review by De Meester and colleagues and provides a more detailed insight into the effectiveness of interventions to promote physical...Full Text Available
BackgroundWith rates of childhood obesity increasing, physical activity (PA) promotion especially in young children has assumed greater importance. Given the limited effectiveness...Full Text Available
Bacterial artificial chromosome (BAC) clones are effective mapping and sequencing reagents for use with a wide variety of small and large genomes. This report describes the development of a physical...Full Text Available
An analysis is given of a survey of the teaching of high energy physics in British universities. The subject changes quickly, and there is a continual conflict between new and old material. Different courses may deal with this in different ways. To find out what is actually being taught to students, details were obtained from all 50 university physics departments in the United Kingdom (UK) by means of a questionnaire. This covered the course structure - whether it was optional or compulsory or contained both elements - the number of lectures given, and the topics covered in the syllabus. The replies give a comprehensive picture of the state of undergraduate teaching of high energy physics in the UK. (Author).
Depending on their unique physical properties, proton and heavy ions have taken an irreplaceable role in modern means of tumor treatment. One-step process and two-step process physical models were employed to explain the mechanism of ion energy loss. The transport process of proton and "1"2C in water was simulated by Geant4 toolkit to study the physical properties of ion beam. The calculation results were discussed, which showed the advantages and disadvantages of proton and "1"2C in the medical application. (authors)
The aim of the report is to describe the state and prospects of the experimental and stand base (ESB) for fundamental investigations in the RF Ministry for Atomic Energy. The ESB includes the following scientific directions: high energy physics, nuclear physics, solid state physics (including superconductivity), plasma physics and controlled thermonuclear synthesis, nuclear reactors and reactor materials testing, lasers, energy conversion and others. Main economical, scientific and technical data on the ESB as a whole and on its most large scientific centers are presented
... Although other authors had made cross-spectral density measurements, Corcos pointed to the importance of this function as indicative of the true ...
hicle [UUV (essentially, a small ex- ploratory submarine robot)] of a type that has been deployed in large numbers in research pertaining to global warm- ...
Photodiode Scintillation Detector for Anticoincidence Shielding An important goal of space research is to understand the physics involved in the activity of ...
Techniques for studying nuclear structure are reviewed. Examples are given of charge density determinations by electron and proton inelastic scattering. (AIP)
We study heavy physics effects on the Higgs production in {gamma}{gamma} fusion using the effective Lagrangian approach. We find that the effects coming from new physics may enhance the standard model predictions for the number of events expected in the final states {bar {ital b}}{ital b}, {ital WW}, and {ital ZZ} up to one order of magnitude, whereas the corresponding number of events for the final state {bar {ital t}}{ital t} may be enhanced up to two orders of magnitude. {copyright} {ital 1996 American Institute of Physics.}
We study heavy physics effects on the Higgs production in #gamma##gamma# fusion using the effective Lagrangian approach. We find that the effects coming from new physics may enhance the standard model predictions for the number of events expected in the final states bar bb, WW, and ZZ up to one order of magnitude, whereas the corresponding number of events for the final state bar tt may be enhanced up to two orders of magnitude. copyright 1996 American Institute of Physics.
The author presents his impressions of the conference - that is - major lessons as presented in the talks on nonlinearities and their role in condensed matter physics. (WRF)
We present the efficient technique to extract the signal of the intermediate mass Higgs boson from the backgrounds at future {gamma}{gamma} colliders. For a clear Higgs detection, it is important to fit the original electron accelerator energy depending on the Higgs mass, to set the polarization of the photon beams and to apply the efficient b quark tagging method. we demonstrate the extraction of information of Higgs parameters and the new physics from the observable physical quantities. It is clearly shown that a future {gamma}{gamma} collider will have a rich potential for study on the new physics, as well as the Higgs physics. (author).
We present the efficient technique to extract the signal of the intermediate mass Higgs boson from the backgrounds at future #gamma##gamma# colliders. For a clear Higgs detection, it is important to fit the original electron accelerator energy depending on the Higgs mass, to set the polarization of the photon beams and to apply the efficient b quark tagging method. we demonstrate the extraction of information of Higgs parameters and the new physics from the observable physical quantities. It is clearly shown that a future #gamma##gamma# collider will have a rich potential for study on the new physics, as well as the Higgs physics. (author).
The Gamma Physics (GaP) program of physical phenomena investigation is proposed on #gamma#p, #gamma#e and #gamma##gamma# colliders at TeV energies. The program contains specialized software (CompHEP system) created for automation of particle interaction processes calculations in the framework of various gauge models. Preliminary physical results are presented (heavy quark production, W, Z production, supersymmetry etc.), and further software development is suggested. (R.P.) 22 refs., 8 figs., 4 tabs.
In this book the notion of time in classical physics and relativity theory is discussed. After a criticism of the absolute time some alternative measures of time in mechanics are considered. Thereafter the problem of equal time at different points of the space as well as the time in different inertial systems are considered. In this framework the clock paradox is discussed. Then the Lorentz transformation is considered. Thereafter the reconstruction of the absolute time in relativity theory is described. Finally the notion of time in general relativity theory is considered.
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 information and ...
Thin films of the protein, lysozyme, have been deposited by the matrix-assisted pulsed laser evaporation (MAPLE) technique. Frozen targets of 0.3-1.0 wt.% lysozyme dissolved in ultrapure water were irradiated by laser light at 355 nm with a fluence of 2 J/cm{sup 2}. The surface quality of the thin lysozyme films of different thickness deposited on 7 mm x 7 mm Si-<1 0 0>-wafers was investigated with scanning electron microscopy and atomic force microscopy. Already at comparatively low thickness, {approx}20 nm, the substrate is covered by intact lysozyme molecules and fragments. The concentration of lysozyme in the ice matrix apparently does not play any significant role for the morphology of the film. The morphology obtained with MAPLE has been compared with results for direct laser irradiation of a pressed lysozyme sample (i.e. pulsed laser deposition (PLD))
More details about the construction of the Terra Nova floating production, storage and offloading (FPSO) vessel are provided. The vessel was built in the Daewoo shipyard in South Korea, and is now undergoing final fitting at Bull Arm, near St. John's, Newfoundland. When complete, the vessel will operate 350 km offshore, southeast of St. John's. It is 291 metres long and 45.5 metres wide and has a capacity of 960,000 barrels of oil. Although the FPSO will hold less than half of the last giant supertanker which sailed for Irving Oil, it has a crew of 81, four times the size of the supertanker, reflecting the technical uniqueness of the vessel and the intense pre-occupation with safety associated with the combination of winds, ice, waves, and shallow water around the Grand Banks. Also described is the alliance system of partnership between the oil companies and the main contractors. The deal stipulates that if the project ran over its budget, the oil ...
Canisters with spent nuclear fuel can obviously not be located within deformation zones as this might jeopardise their long term mechanical stability and thereby constitute a potential hazard to the biosphere. Less apparent, but equally important, is the fact that earthquakes trigger reactivation, slip, of structures some distance from their hypocentres due to, among many other factors, stress redistribution. Fault slip across a deposition hole might damage the isolation capacity of the canister and thereby jeopardise the overall integrity of the barrier system. Therefore, the following question might be posed: What is the distance from a deformation zone beyond which a canister can be safely emplaced? This respect distance cannot be readily computed because, unknown future events aside, there are some complicated aspects that need to be addressed e.g. degree of conservatism, scale, our ability to model ice sheets and earthquakes, etc. In this report we discuss ...
In 1982 the semi-submersible drilling unit Ocean Ranger capsized and sank off the Grand Banks, resulting in the loss of the entire 84-man crew. A Royal Commission was set up to conduct an enquiry into the incident, and to carry out a process of research and opinion-gathering towards providing recommendations to both federal and Newfoundland governments. The primary purpose of the Commission was to determine why the Ocean Ranger sank, why none of the crew were saved, and how to avoid similar disasters. A number of studies and seminars were held to focus expert knowledge and opinion in several key fields and to update studies and fill gaps in the data base. Summaries of selected study reports and the seminar proceedings are presented in the following areas: the environment, including ice, marine climatology, weather forecasting services, wave climatology, oceanographic information, and seabed information; design, including mobile offshore drilling rig design ...
Propylene and ethylene glycol deicers are commonly used at airports in the US and other countries to remove and retard the accumulation of snow and ice on aircraft. Deicers may not only enter water bodies without treatment, due to excessive storm-related flow, but also may expose terrestrial organisms to high concentrations through surface runoff. Most available toxicity data are for aquatic vertebrates and invertebrate species; this study examined effects on terrestrial and aquatic plants. Terrestrial plant species included both a monocot (rye grass, Lolium perenne) and a dicot (lettuce, Lactuca saliva). Aquatic species included a single cell alga (Selenastrum capricomutum), and an aquatic macrophyte (duckweed, Lemna minor). Glycol deicers were obtained in the formulated mixtures used on aircraft. Pure ethylene and propylene glycol were obtained from Sigma{reg_sign}. Parameters measured included germination, root and shoot length, survival, and growth. Formulated ...
The effect of longer ice-free periods on the seasonal variation and total annual values of phytoplankton primary production was considered along with the efficiency and productivity of the phytoplankton communities at different water temperatures by constant light. The studied pond, Vasikkalampi, is located in the town Jvyaskyla in central Finland. The pond is slightly eutrophic and its water is used for cooling purposes by a 35 MW thermal powerplant. The cooling water is taken in the middle of the pond and it returns as heated effluent to the northern part, near the surface, about 100 m from the intake pipe. This circulation and warming of the water keeps the pond open throughout the year except during the coldest weeks in the winter when some parts freeze over. The increase of the water temperature was not sufficient to be optimal for photosynthesis in the spring. The phytoplankton biomass starts to increase early in the spring when the zooplankton grazing ...
The in-flight wavelength calibration for the Ozone Monitoring Instrument is discussed. The observed variability in the wavelength scale is two orders of magnitude larger than caused by temperature changes in the instrument. These wavelength variations are the result of rapid changes in time in the radiance levels during an individual observation in the presence of clouds or snow and ice. We have developed a data processing method to account and correct for these changes. In February 2005 this correction was implemented in the official data processing stream. We explain in detail how and how accurately this method works. Before correction, the error in the wavelength scale can be as much as a few tenths of a pixel; after correction it is mostly less than 1/100th of a pixel, which is the required preflight accuracy. This means that higher-level products such as the total column amounts of ozone, NO2, and SO2 are not significantly affected. It is expected that these ...
In the advance of fuel cell electric vehicles (EV), hybrid electric vehicles (HEV) can contribute to reduced emissions and energy consumption of personal cars as a short term solution. Trade-offs reveal better emission control for series hybrid vehicles, while parallel hybrid vehicles with different drive trains may significantly reduce fuel consumption as well. At present, costs and marketing considerations favor parallel hybrid vehicles making use of small, high power batteries. With ultra high power density cells in development, exceeding 1 kW/kg, high power batteries can be provided by adapting a technology closely related to consumer cell production. Energy consumption and emissions may benefit from regenerative braking and smoothing of the internal combustion engine (ICE) response as well, with limited additional battery weight. High power supercapacitors may assist the achievement of this goal. Problems to be solved in practice comprise battery management to ...
If the first (PopIII) stars were very massive, their final fate is to collapse into very massive black holes. Once a proto-black hole has formed into the stellar core, accretion continues through a disk. It is widely accepted, although not confirmed, that magnetic fields drive an energetic jet which produces a burst of TeV neutrinos by photon-meson interaction, and eventually breaks out of the stellar envelope appearing as a Gamma Ray Burst (GRB). Based on recent numerical simulations and neutrino emission models, we predict the expected neutrino diffuse flux from these PopIII GRBs and compare it with the capabilities of present and planned detectors as AMANDA and IceCube. If beamed into 1% of the sky, we find that the rate of PopIII GRBs is $\\le 4 \\times 10^6$ yr$^{-1}$. High energy neutrinos from PopIII GRBs could dominate the overall flux in two energy bands [$10^4 - 10^5$] GeV and [$10^5 - 10^6$] GeV of neutrino telescopes. The enhanced sensitivities of ...
Effects of ethanol in vitro on membrane vesicles were evaluated by monitoring "3"6Cl"- influx. Different assay parameters were tested to determine increased or decreased action of ethanol on GABA-activated chloride channels. The ability of 30 mM ethanol to augment "3"6Cl"- flux was seen at 0 degree C, in the absence of GABA, and at 34 degree C in the presence of GABA, using two different assay procedures. Picrotoxin blocked the direct effects of ethanol suggesting GABA_a involvement. Endogenous GABA in the medium surrounding the microsacs was assayed at different temperatures both in the presence and absence of GABA and ethanol. The direct effect of ethanol did not appear to involve the action of endogenous GABA. In addition to temperature effects on the assay, time of membrane storage also influenced ethanol action. Microsacs stored on ice for 2 hours or more lost their ability to respond to ethanol but not to GABA, pentobarbital or flunitrazepam. When these drugs ...
Local blood flow in the thigh was measured with /sup 133/Xe clearance technique in eight male distance runners after compression with a foam rubber compress and a standard elastic bandage. Two degrees of compression were tested, and an initial experiment with rested subjects was followed by a similar experiment immediately after running. Maximum compression exerted a cutaneous pressure of 85 (+/- 8) mm Hg and caused an immediate cessation of intra-muscular blood flow in the compressed area. Moderate compression gave a cutaneous pressure of 40 (+/- 5) mm Hg and resulted in a reduction of blood flow by approximately 50%. During compression, there were no significant differences in the blood flow of rested subjects compared to subjects immediately after running. In acute soft tissue injuries, a maximum compression bandage should effectively reduce or eliminate the formation of an intra-muscular hematoma, and an additive effect on blood flow of ice should not be ...
The report was prepared for the IPCC by Working Group II. The remit of Working Group II was to describe the environmental and socioeconomic implications of possible climate changes over the next decades caused by increasing concentrations of greenhouse gases. The scenarios used include the following features: an effective doubling of atmospheric CO{sub 2} between now and 2025-2050; a consequent increase of global mean temperature of 1.5-4.5{degree}C; an unequal global distribution of the temperature increase; a sea level rise of 0.3 to 0.5m by 2050. The impacts of possible climate change were assessed for the following: agriculture and forestry; natural terrestrial ecosystems; hydrology and water resources; human settlements including the energy, transport and industrial sectors; human health; air quality and changes in UV-B radiation; oceans and coastal zones; seasonal snow cover; ice and permafrost. Further action is recommended. 1015 refs., 34 figs., 26 tabs.
In 1990, 176 million tonnes (mt) of air-traffic fuel was burned, which produced about 550 mt CO{sub 2}, 220 mt water, 3.5 mt NO{sub x} amd 0.18 mt SO{sub 2}. NO{sub x} emissions from air traffic may, by increasing ozone concentrations, be responsible for about 8% of global greenhouse warming. In the stratosphere NO{sub x} from aircraft is partly responsible for ozone depletion. With present technology 500 aircraft in the stratosphere would cause global ozone losses of 20%. Water vapour added by aircraft also contributes to global warming. In the form of ice crystals between 8 to 13 km above sea level, it acts as cirrus clouds. Probably the least damaging cruising altitude for aircraft is 9 km above sea level. Fuel consumption by aircraft is increasing. Air pollution abatement measures include substituting hydrogen fuel for kerosene, developing engines that emit less NO{sub x} and the introduction of internationally negotiated taxes on kerosene. 30 refs.
This paper contains literature from American Power Conference Air Toxics Being Measured Accurately, Controlled Effectively NO{sub x} and SO{sub 2} Emissions Reduced; Surface Condensers Improve Heat Rate; Usable Fuel from Municipal Solid Waste; Cofiring Technology Reduces Gas Turbine Emissions; Trainable, Rugged Microsensor Identifies of Gases; High-Tc Superconductors Fabricated; High-Temperature Superconducting Current Leads; Vitrification of Low-Level Radioactive and Mixed Wastes; Characterization, Demolition, and Disposal of Contaminated Structures; On-Line Plant Diagnostics and Management; Sulfide Ceramic Materials for Improved Batteries; Flywheel Provides Efficient Energy Storage; Battery Systems for Electric Vehicles; Polymer-Electrolyte Fuel Cells for Transportation; Solid-Oxide Fuel Cells for Transportation; Surface Acoustic Wave Sensor Monitors Emissions in Real-Time; Advance Alternative-Fueled Automotive Technologies; Thermal & Mechanical Process; Flow-Induced Vibration ...
There are 13 Electron Beam Ion Sources in operation which produce highly charged ions, up to Th[sup 80+] and Xe[sup 53+]. Most of the sources are used to study these ions under electron impact or when recombining with gaseous or solid targets. That provides an insight into the atomic physics of these highly charged ions and into the physics of the plasma in which such ions can be found. This paper reviews the present knowledge of atomic processes, important in the production of such ions with an EBIS.
There are 13 Electron Beam Ion Sources in operation which produce highly charged ions, up to Th{sup 80+} and Xe{sup 53+}. Most of the sources are used to study these ions under electron impact or when recombining with gaseous or solid targets. That provides an insight into the atomic physics of these highly charged ions and into the physics of the plasma in which such ions can be found. This paper reviews the present knowledge of atomic processes, important in the production of such ions with an EBIS.
We have conducted a systematic investigation of the origin and underlying physics of the line--line and line--continuum correlations of AGNs, particularly the Baldwin effect. Based on the homogeneous sample of Seyfert 1s and QSOs in the SDSS DR4, we find the origin of all the emission-line regularities is Eddington ratio (L/Ledd). The essential physics is that L/Ledd regulates the distributions of the properties (particularly column density) of the clouds bound in the line-emitting region.
We report on the activities of the High Energy Physics Group at the University of Texas at Arlington for the period 1994-95. We propose the continuation of the research program for 1996-98 with strong participation in the detector upgrade and physics analysis work for the D0 Experiment at Fermilab, prototyping and pre-production studies for the muon and calorimeter systems for the ATLAS Experiment at CERN, and detector development and simulation studies for the PP2PP Experiment at Brookhaven.
Research performed at LAMPF during 1985 is reported in the areas of: nuclear and particle physics; atomic and molecular physics; materials science; radiation-effects studies; biomedical research and instrumentation; nuclear chemistry; radioisotope production; and physics theory. Also reported are the status of LAMPF-II, facility development work, and accelerator operations. (LEW)
In this paper some physical mechanisms are described, which determine some new free-electron laser configurations. These mechanisms comprise some physical effects of the radiant emission of an electron beam at the interaction with the medium it is crossing. They are based on the Cherenkov effect, Smith-Purcell effect, optical klystron, Rumakhov effect and limited interaction effect. (Author).
The Tevatron Run 2 has begun. The Tevatron program in the next six years offers a real opportunity to significantly advance our understanding of the fundamental properties of the universe. It is an exciting, challenging program that goes straight to the highest priorities of high energy physics worldwide. The accelerator and detectors are being commissioned and seem to be performing well. We anticipate first physics results in the summer of 2002.
We study heavy physics effects on the Higgs production in #gamma##gamma# fusion using the effective Lagrangian approach. We find that the effects coming from new physics may enhance the standard model predictions for the number of events expected in the final states b-barb, WW, and ZZ up to one order of magnitude, whereas the corresponding number of events for the final state t-bart may be enhanced up to two orders of magnitude.
The complementarity of e{sup +}e{sup -} and {gamma}{gamma} colliders to discover and explore new physics beyond the Standard Model (SM) is discussed. After briefly surveying a number of various new physics scenarios, we concentrate in detail on signatures for Large Extra Dimensions via the process {gamma}{gamma}{yields}WW.
The complementarity of e"+e"- and #gamma##gamma# colliders to discover and explore new physics beyond the Standard Model (SM) is discussed. After briefly surveying a number of various new physics scenarios, we concentrate in detail on signatures for Large Extra Dimensions via the process #gamma##gamma##->#WW.
The complementarity of e{sup +}e{sub {minus}} and gamma-gamma colliders to discover and explore new physics beyond the Standard Model (SM) is discussed. After briefly surveying a number of various new physics scenarios the authors concentrate in detail on signatures for Large Extra Dimensions via the process gamma-gamma --> WW.
We discuss the main stages of a physical program for photon linear colliders. We consider the problems in electroweak theory, hadron physics, QCD, and nonlinear QED, as well as new particles and interactions, etc. The discussed stages constitute the parts of an entire ambitious program for linear colliders. ((orig.)).
This volume contains the annual report describing the work carried out at COSY (Cooled Synchrotron Storage Ring at KFA Juelich). The results in both machine and physics program are presented on the main topics experimental nuclear physics, theoretical nuclear physics, accelerator developments and technical developments. (MSA)
...Modern Languages Music Philosophy Faculty of Medicine Faculty of Medicine page Academic unit: Medicine Faculty of Natural and Environmental Sciences Faculty of Natural and Environmental Sciences page Academic units: Biological Sciences Chemistry National Oceanography Centre, Southampton Ocean and Earth Science Faculty of Physical and Applied Sciences Faculty of Physical and Applied Sciences page Academic units: Electronics and Computer Science Optoelectronics Research Centre Physics and Astronomy Faculty of Social and Human Sciences ...
The complex aspects of high energy physics work are briefly described, and approaches to managing them are discussed. Management of software and data are covered. For managing complexity in experimental physics, the choice of building or buying processor systems is addressed and the issues of compatibility and standardization are discussed. (LEW)
This is an account of the initial struggles and subsequently successful career of a young woman growing up in prewar Australia with the overriding desire to become a physicist despite various problems and prejudices. The book provides first-hand accounts of wartime radar research and development in Australia; the immediately post-war era in nuclear physics at the Cavendish Laboratory, Cambridge; and work in the Nuclear Physics Division at AERE Harwell in the period from the 1950s onwards. (UK).
Southeastern Finland belongs to the area covered by the Weichselian ice sheet, where the release of the ice load caused a rapid isostatic rebound during the postglacial time. While the mean overall apparent uplift is of the order of 2 mm/yr today, in the early Holocene time it was several times higher. A marked decrease in the rebound rate occurred around 8500 BP, however, since then the uplift rate has remained high until today, with a slightly decreasing trend towards the present time. According to current understanding there have neither been temporary increases nor decreases in the rate of uplift during the postglacial time. Even so, it is not known for sure whether there are regional irregularities on the rebound in Finland. Concurrently with land uplift, relative sea-level changes in the Baltic basin were also strongly affected by the global eustatic rise of sea-level. During the early Litorina Sea stage on the southern coast of Finland ...
Researchers have identified as effective and worthy of broader dissemination a variety of intervention strategies to promote physical activity among older adults. This paper reports results of a community-organizing approach to disseminating evidence-based interventions in a sustainable way: The Southeast Seattle Senior Physical Activity Network (SESPAN). SESPAN was implemented in Southeast Seattle, a group of multicultural neighborhoods extending 8?miles southeast of downtown Seattle, with a population of 56,469 in 2000, with 12% (7,041) aged 65 and older. The SESPAN organizing strategy involved networking to: (1) make connections between two or more community organizations to create new senior physical activity programs; and (2) build coalitions of community groups and organizations to a...
In the paper the role of conservation laws in evolutionary processes, which proceed in material systems (in material media) and lead to generation of physical fields, is shown using skew-symmetric differential forms. In present paper the skew-symmetric differential forms on deforming (nondifferentiable) manifolds were used in addition to exterior forms, which have differentiable manifolds as a basis. Such skew-symmetric forms (which were named evolutionary ones since they possess evolutionary properties), as well as the closed exterior forms, describe the conservation laws. But in contrast to exterior forms, which describe conservation laws for physical fields, the evolutionary forms correspond to conservation laws for material systems. The evolutionary forms possess an unique peculiarity, namely, the closed exterior forms are obtained from these forms. It is just this that enables one to describe the process of generation of ...
Towards the end of the 19th century, Kelvin pronounced as the "clouds of physics" 1) the failure of the Michelson-Morely experiment to detect an ether wind, 2) the violation of the classical mechanical equipartition theorem in statistical thermodynamics. And he believed that the removal of these clouds would bring physics to an end. But as we know, the removal of these clouds led to the two great breakthoughts of modern physics: 1) The theory of relativity, and 2) to quantum mechanics. Towards the end of the 20th century more clouds of physics became apparent. They are 1) the riddle of quantum gravity, 2) the superluminal quantum correlations, 3) the small cosmological constant. Furthermore, there is the riddle of dark energy making up 70% of the physical universe, the non-baryonic cold dark matter making up 26% and the very small initial entropy of the universe. An attempt is made ...
The volume examines the scientific interfaces and technological applications of physics. Twelve areas are dealt with: biological physics--biophysics, the brain, and theoretical biology; the physics-chemistry interface--instrumentation, surfaces, neutron and synchrotron radiation, polymers, organic electronic materials; materials science; geophysics--tectonics, the atmosphere and oceans, planets, drilling and seismic exploration, and remote sensing; computational physics--complex systems and applications in basic research; mathematics--field theory and chaos; microelectronics--integrated circuits, miniaturization, future trends; optical information technologies--fiber optics and photonics; instrumentation; physics applications to energy needs and the environment; national security--devices, weapons, and arms control; medical physics--radiology, ultrasonics, NMR, ...
English abstract: In the "Intuitive Quantum Physics" course, we use graphical interpretations of mathematical equations and qualitative reasoning to develop and teach a simplified model of quantum physics. Our course contains three units: Wave physics, Development of a conceptual toolbox, and quantum physics. It also contains three key themes: wave-particle duality, the Schroedinger equation, and tunneling of quantum particles. Students learn most new material in lab-tutorials in which students work in small groups (3 to 3 people) on specially designed worksheets. Lecture reinforces the lab-tutorial content and focuses more on issues about the nature of science. Data show that students are able to learn some of the most difficult concepts in the course, and also that students learn to believe that there is a conceptually accessible structure to the physics in the course. German ...
We present the latest developments for the radiation laboratory curriculum at the Department of Physics and Astronomy of Western Kentucky University. During the last decade, the Applied Physics Institute (API) at WKU accumulated various equipment for radiation experimentation. This includes various neutron sources (computer controlled d-t and d-d neutron generators, and isotopic 252 Cf and PuBe sources), the set of gamma sources with various intensities, gamma detectors with various energy resolutions (NaI, BGO, GSO, LaBr and HPGe) and the 2.5-MeV Van de Graaff particle accelerator. XRF and XRD apparatuses are also available for students and members at the API. This equipment is currently used in numerous scientific and teaching activities. Members of the API also developed a set of laboratory activities for undergraduate students taking classes from the physics curriculum (Nuclear Physics, Atomic ...
ABSTRACT. Field methods for determining the sex of birds are often limited due to morphometric overlap between sexes, intermediate plumages, seasonality, and reliance on subjective age classification. Interpubic distance, characterized in birds as the distance between the distal ends of the pubic bones, has not been formally tested as a method for determining the sex of birds, despite references among parrot breeders and the frequent use of analogous measurements in mammals. We developed a harmless and easily performed field method for measuring interpubic distance in studies involving bird capture, and compared the interpubic distances of known sex White-ruffed Manakins (Corapipo altera), Orange-collared Manakins (Manacus aurantiacus), and Blue-crowned Manakins (Lepidothrix coronata) to e...
This paper contributes to an understanding of pharmacogenomics-in-the-making by foregrounding a regulatory setting in which these technologies must be situated: decision-making about pharmaceutical reimbursement. Health care assessment organizations have been introduced in many countries to systematically address the issue of health care coverage. Using the example of Sweden, the process of deciding reimbursement status is shown to hinge on the creation of stable and clinically feasible categories of patients, diseases and drug responses. Through a series of analogous examples concerning conventional pharmaceuticals, it is argued that current mechanisms for categorizing reimbursable drugs could be upset when pharmacogenomic advances provide a means of making patients more specific objects ...
A transient-enhanced diffusion has been observed during the furnace or rapid thermal annealing of ion-implanted silicon. We have studied this transient in detail and show that, for doses of Group V dopants sufficient to amorphize the silicon, it arises from the trapping of interstitials by dopant atoms during implantation. These are retained during solidphase-epitaxial (SPE) growth, but can be released by additional thermal processing to cause the observed transient and the formation of a band of extended defects. We have measured the enhanced diffusion coefficients and the duration of the transient for Sb-implanted Si by careful furnace annealing experiments. We obtain general expressions which predict the effects of the transient during any thermal processing based on SPE growth (furnace, CW laser, or rapid thermal annealing). We show that there is no analogous mechanism of vacancy trapping by Group III elements.
A transient-enhanced diffusion has been observed during the furnace or rapid thermal annealing of ion-implanted silicon. We have studied this transient in detail and show that, for doses of Group V dopants sufficient to amorphize the silicon, it arises from the trapping of interstitials by dopant atoms during implantation. These are retained during solidphase-epitaxial (SPE) growth, but can be released by additional thermal processing to cause the observed transient and the formation of a band of extended defects. We have measured the enhanced diffusion coefficients and the duration of the transient for Sb-implanted Si by careful furnace annealing experiments. We obtain general expressions which predict the effects of the transient during any thermal processing based on SPE growth (furnace, CW laser, or rapid thermal annealing). We show that there is no analogous mechanism of vacancy trapping by Group III elements.
The group- V vacancy pair, the so-called E-center, has recently been demonstrated to have, both in Si and Ge, more complicated energy-level schemes in the energy gap than were previously assumed. The E-center in silicon has, in addition to its well-established single-acceptor level in the upper half of the band gap, also a donor level in the lower half of the band gap; this donor level has lain hidden for more than 40 years. The E-center in Ge has an even more complicated level scheme as it induces, in addition to two levels analogous to those found in Si, also a double-acceptor level in the upper half of the band gap. Thus the E-center in Si can exist in three charge states and the E-center in Ge in four.
We aimed to investigate the effects of local anesthetics soaked in Merocel nasal packs on hemorrhage and pain after septoplasty. The methodology includes a prospective double-blind study that was conducted in patients undergoing septoplasty because of nasal septal deviation. The study included 143 patients. The patients were divided into four groups. Each group received 1% lidocaine?+?0.000625% adrenalin, 0.375% ropivacaine, 0.25% bupivacaine as study groups or 0.9% sodium chloride as a control group in their Merocel packs postoperatively. The local anesthetics or sodium chloride were reapplied at the eighth postoperative hour. Each patient was given a questionnaire where verbal analog score and amount of postoperative hemorrhage was noted. The statistical analysis was performed using two ...
By means of an analogous simulator, which can simulate a power supply system, a method to determine the transfer function of a Power System Stabilizer (PSS) is developed. The purpose of the PSS is to damp unwanted electro-mechanical oscillations. The method is very systematic and there is no need for specified values of the parameters used in the system. It is assumed that the power generator system is linear for small variations. The system can be considered to be a black box. Measurements executed by means of this method are completely controlled by the person who enforces the measurement. By applying this method carefully, irregularities are almost out of the question. The equipment necessary are a PC with two AD-ports and an adjustable sinus-generator. A comparison is made with a more traditional method, in which a spectrum analyzer is used. 4 figs., 7 refs.
Methods for the synthesis and quantitation of the novel choline analogues, telluronium choline and acetyltelluronium choline, are described. An assay procedure utilizing pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) with cold trapping was developed with [2H4]telluronium choline and [2H4]acetyltelluronium choline as internal standards. The telluronium compounds were ion-pair extracted from tissue with dipicrylamine, washed with 2-butanone, and pyrolyzed prior to GC-MS analysis. The compounds were monitored using selected ion monitoring at m/z 232 and m/z 190 for acetyltelluronium and telluronium choline, respectively, and at m/z 236 and m/z 194 for the analogous deuterated internal standards. The assay was linear over a range of 20 pmol-20 nmol of compound taken through the assay. PMID:8130881
We have developed a method for the synthesis of C-11 iodoantipyrine. Carbon-11-labeled methyl iodide, prepared from /sup 11/CO2, was used to methylate 3-methyl-1-phenyl-2-pyrazolin-5-one to form C-11 antipyrine. Following silica-gel column chromatography and iodination, radiochemical purity of the C-11 iodoantipyrine was more than 99.5%, with a 10% yield and a specific activity of 30 mCi/mumol. Preliminary animal studies showed complete cerebral extraction and local cerebral blood-flow values that were within 4.6% of those obtained using C-14 iodoantipyrine. The C-11 analog, with positron emission tomography, will facilitate local cerebral blood-flow studies in human subjects.
Mono- and disubstituted novel derivatives of the heptaene nystatin analog 28,29-didehydronystatin A1 (S44HP, 1) were obtained by chemical modification of the exocyclic C-16 carboxyl and/or an amino group of mycosamine moiety. The strategy of preparation of mono- and double-modified polyene macrolides was based on the use of intermediate hydrophobic N-Fmoc (9-fluorenylmethoxycarbonyl) derivatives that facilitated the procedures of isolation and purification of new compounds. The antifungal activity of the new derivatives was first tested in vitro against yeasts and filamentous fungi, allowing the selection of the most active compounds that were subsequently tested for acute toxicity in mice. 2-(N,N-dimethylamino)ethylamide of 1 (2) and 2-(N,N-dimethylamino)ethylamide of N-fructopyranosyl-28...
We present experimental studies on the photoionization and photodissociation processes (photodestruction) of gaseous amino acids and nucleobases in interstellar and interplanetary radiation conditions analogs. The measurements have been undertaken at the Brazilian Synchrotron Light Laboratory (LNLS), employing vacuum ultraviolet (VUV) and soft X-ray photons. The experimental set up basically consists of a time-of-flight mass spectrometer kept under high vacuum conditions. Mass spectra were obtained using photoelectron photoion coincidence technique. We have shown that the amino acids are effectively more destroyed (up to 70-80%) by the stellar radiation than the nucleobases, mainly in the VUV. Since polycyclic aromatic hydrocarbons have the same survival capability and seem to be ubiquitous in the ISM, it is not unreasonable to predict that nucleobases could survive in the interstellar medium and/or in comets, even as a stable cation.
Irradiation of EP-823 (16Cr12MoWsiVNbB) ferritic-martensitic steel with 7-MeV Ni++ ions and with 30- and 70-keV He+ ions at a temperature of 500?C was followed by an increase in the microhardness, which was due to both radiation point defects and changes in the phase composition and the dislocation structure of the steel. It was found that the dependence of the largest relative increase in the microhardness on the concentration of radiation-induced point defects in the near-surface region of the steel under irradiation with different ions correlated with an analogous dependence of the surface segregation of silicon and chromium.
We have investigated the superconducting and metallurgical properties of the ternary compounds RPd_2Si_2 and RRh_2Si_2 with R = Y, La, and Lu. All RPd_2Si_2 compounds and LaRh_2Si_2 were found to be type-I superconductors below 1 K. A detailed metallurgical analysis shows that segregation of second phases can easily mask the intrinsic (stoichiometric ratio 1:2:2) intermetallic-compound properties. Two sample-preparation techniques, viz., single crystals and off-stoichiometry, were utilized to establish where bulk superconductivity occurs. The type-I behavior of these compounds is explained with an analogous model as is used for the heavy-fermion superconductors CeCu_2Si_2 and URu_2Si_2.
Contradictory reports in the literature on the reliability of lymphography stimulated the authors to test the diagnostic accuracy, employing methods which are approximately analogous to practice, using carcinoma of the cervix as the model on which the study was carried out. Using 21 observers it was found that there was no correlation between their experience and on-target accuracy of the diagnosis. Good observers obtained an accuracy of 85% with good proportions between sensitivity in the recognition of detail, specificity and readiness to arrive at a decision on the basis of discriminatory ability. With the help of the concept of the ROC curves, the position taken up by the observers in respect of diagnostic decisions, and a complex manner of assessing the various characteristic factors determining diagnostic accuracy, are demonstrated. This form of test, which permits manipulation of different variants of diagnosis, is recommended, among other things, for ...
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 ...
We report here results of an application of single-nucleon stripping reactions at high energies (65 MeV/u) in inverse kinematics to obtain spectroscopic factors. From measurements of the partial cross-sections for ground and excited states in residual nuclei formed in one-proton stripping reactions, single particle orbits and occupancies of light nuclei have been studied in the s-d shell. Single proton stripping cross-sections of {sup 25}Al and {sup 26,27,28}P on a Be target have been measured using the S800 spectrograph and the NaI(Tl) array at the NSCL. These results indicate that this technique may provide a general tool for the intermediate energy range analogous to transfer (pick-up) reactions at low-energy.
We report here results of an application of single-nucleon stripping reactions at high energies (65 MeV/u) in inverse kinematics to obtain spectroscopic factors. From measurements of the partial cross-sections for ground and excited states in residual nuclei formed in one-proton stripping reactions, single particle orbits and occupancies of light nuclei have been studied in the s-d shell. Single proton stripping cross-sections of "2"5Al and "2"6","2"7","2"8P on a Be target have been measured using the S800 spectrograph and the NaI(Tl) array at the NSCL. These results indicate that this technique may provide a general tool for the intermediate energy range analogous to transfer (pick-up) reactions at low-energy.
A four-stage scoring system for brain maturation was established with MR imaging. First, gyration and myelination were analyzed in 50 anamnestically normal children (32-240 weeks postconceptional age). Subsequently 60 patients (same age range) with birth asphyxia, seizures, or developmental delays were evaluated analogously. T1- and T2-weighted images (500/30 and 3,000/120 [repetition time msec/echo time msec]) were obtained with a 2.35-T magnet in all children. Whereas gyration abnormalities were seen in some patients, all handicapped children presented with delayed myelination. In conclusion, prospective staging of brain development (gyration and myelination) is possible and is best obtained with T2-weighted images.
Aqueous radioactive high-level waste slurries are combined during processing steps that ultimately produce a stable borosilicate glass waste form. Chemically treated waste slurries are combined with each other and with glass frit-water slurries to produce the melter feed. Understanding the evolution of the rheological properties of the slurries is an important aspect of removing and treating the stored waste. To a first approximation, combinations of colloidal waste slurry with {approx}0.1-mm mean diameter glass frit or glass beads act in an analogous matter to slurries of spherical beads in Newtonian liquids. The non-Newtonian rheological properties of the waste slurries without frit, however, add complexity to the hydrodynamic analysis. The use of shear rate dependent apparent viscosities with the modified Einstein equation was used to model the rheological properties of aqueous frit-waste slurries.
Serum growth hormone (GH) was suppressed in female rats bearing mammary tumors induced by 7, 12, dimethylbenz(a)anthracene (DMBA) or N-nitrosomethylurea(NMU). Serum GH was suppressed due to treatment with a human GH analog produced by the plerocercoid stage of the tapeworm Spirometra mansonoides. Rats treated with plerocercoid growth factor (PGF) via plerocercoid infection had accelerated growth rates despite marked reductions in GH levels. Approximately two-thirds of the mammary tumors induced by either DMBA or NMU regressed during three weeks of exposure to PGF while most of the control tumors continued to grow. The data support an important regulatory role for GH in growth of mammary tumors in rats. PMID:3019224
The paper outlines the design, principles of operation, and calibration of a five-IC network intended to give a rapid, precise, and automatic determination of the flatband voltage of MOS capacitors. The basic principle of measurement is to compare the analog output voltage of a capacitance meter - which is directly proportional to the capacitance being measured - with a preset or dialed-in voltage proportional to the calculated flatband capacitance by means of a comparator circuit. The bias to the MOS capacitor supplied through the capacitance meter is provided by a ramp voltage going from a negative toward a positive voltage level and vice versa. The network employs two monostable multivibrators for reading and recording the flatband voltage and for resetting the initial conditions and restarting the ramp. The flatband voltage can be held and read on a digital voltmeter.
Purpose - This paper aims to discuss the procedures and methods developed at Washington State University to digitize and make accessible historic moving images. Design/methodology/approach - The paper describes the selection and the use of low-cost technologies to transfer analog film to digital formats. Issues related to the conversion, description, and online hosting of digital films are also addressed. Findings - Though the steps involved in digitizing film are not trivial, the benefits of access both for the public and archives staff outweigh the expense and labor involved. The procedures described in this paper involve low upfront costs and are sustained through cost recovery fees. Research limitations/implications - The focus of this paper is on managing, describing, and providing on...
The full theory and the semiclassical description of loop quantum cosmology (LQC) have been studied in the Friedmann-Robertson-Walker and Bianchi I models. As an extension to include both anisotropy and intrinsic curvature, this paper investigates the cosmological model of Kantowski-Sachs spacetime with a free massless scalar field at the level of phenomenological dynamics with the LQC discreteness corrections. The LQC corrections are implemented in two different improved quantization schemes. In both schemes, the big bang and big crunch singularities of the classical solution are resolved and replaced by the big bounces when the area or volume scale factor approaches the critical values in the Planck regime measured by the reference of the scalar field momentum. Symmetries of scaling are also noted and suggest that the fundamental spatial scale (area gap) may give rise to a temporal scale. The bouncing scenarios are in an analogous fashion of the Bianchi I model, ...
Two approaches are used to analyse X-ray or neutron scattering by crystals with different dislocation ensembles. Analogy between the above concepts is discussed. The microscopical approach takes into account the detailed displacement field due to different types of dislocation arrangement in the crystal. Frequently a phenomenological concept operating with the ideas of displacements, strains and stresses arising in the materials under deformation is applied. Unfortunately, the phenomenological concept cannot take into account that similar stress distributions may have significantly different microscopic reasons. The comparison of the results obtained by both phenomenological and microscopic descriptions of scattering enables us to understand the connection between different types of strains and stresses in the crystal with the type of the defects in it. (orig.)
Two new triterpene glycosides, patagonicosides B and C (2 and 3, resp.), together with the known patagonicoside A (1), have been isolated from the EtOH extract of the sea cucumber Psolus patagonicus. The structures of the new compounds were established on the basis of extensive NMR spectroscopic analysis ((1)H- and (13)C-NMR, (1)H,(1)H-COSY, HMBC, HSQC, TOCSY, and NOESY), HR-ESI-MS data, and chemical transformations. Compounds 1-3 and their desulfated analogs showed antifungal activities against the phytopathogenic fungus Cladosporium cladosporoides in a dose-dependent fashion. PMID:21404430
Abstract Introduction.- Sling erosion/extrusion is a complication after suburethral sling insertion for female stress urinary incontinence that occurs in approximately 6% of patients. Symptoms may include vaginal discharge, infections, postcoital bleeding, and alterations of the sexual function. Little is known about the effect of sling erosion on the sexual function of the male partner. Aim.- The aim of this study was to determine male sexual function in partners of women who had undergone sling insertion for stress urinary incontinence and who developed sling erosion postoperatively. Main Outcome Measures.- Main outcome measures were the Brief Male Sexual Function Inventory (BMSFI) and visual analog scale (VAS) scores. Methods.- Male partners of patients who presented with sling erosion ...
The alliance of J. Robert Oppenheimer, scientist, and Leslie R. Groves, military leader, is often interpreted as the classic example of the clash between the academic mind and the military style. Evidence suggests, instead, that it was a collaboration that led to the dawn of the nuclear age. Instead of a clash, it was collaboration and an implosion of the diverse talents needed for the success of this project. Discussion of these flawed and fascinating individuals still ignites controversy today. This presentation will explore the backgrounds and personalities of these two men and their work together to accomplish their mission. Was the aftermath inevitable, given a relationship based on respect, but perhaps not trust? The genesis of the modern military-industrial complex rested on the genius of these two men, though they personify two distinct American sub-cultures. What lessons can be drawn from their wartime and post-war relationship? What analogies can be drawn ...
A macroscopic realization of the strange virtual particles is presented. The classical Helmholtz and the quantum mechanical Schr\\"odinger equations are analogous differential equations. Their imaginary solutions are called evanescent modes in the case of elastic and electromagnetic fields. In the case of non-relativistic quantum mechanical fields they are called tunneling solutions. The imaginary solutions of this differential equation point to strange consequences: They are non local, they are not observable, and they described as virtual particles. During the last two decades QED calculations of the imaginary solutions have been experimentally confirmed for phonons, photons, and for electrons. The experimental proofs of the predictions of the non-relativistic quantum mechanics and of the Wigner phase time approach for the elastic, the electromagnetic and the Schr\\"odinger fields will be presented in this article. The results are zero tunneling time and an ...
Although state estimation is a mature technique which is widely available in the EMS industry, experience with practical implementation and use of state estimation and network security analysis functions at electric power utilities over the last two decades indicates recurring difficulties and problems attributable to inadequate external network modeling detail and data. This paper addresses the development of a set of guidelines for external network modeling and data exchange, based on the results of a recent project sponsored by EPRI. A general methodology is developed based on the results of a survey of a representative set of utilities and EMS suppliers, supplemented by subsequent analysis and simulation studies. Distinction is made between guidelines pertaining to external network topology, analog measurements, data exchange, and implementation procedures. A philosophy and approach for constructing and testing external models is also presented.
The problem of a spin 1 charged particle with electromagnetic polarizability, obeying a generalized 15-component quantum mechanical equation, is investigated in presence of the external Coulomb potential. With the use of the Wigner's functions techniques, separation of variables in the spherical tetrad basis is done and the 15-component radial system is given. It is shown that there exists a class of quantum states for which the additional characteristics, polarizability, does not manifest itself anyhow; at this the energy spectrum of the system coincides with the known spectrum of the scalar particle. For j=0 states, a 2-order differential equation is derived, it contains an additional potential term 1/r^{4}. In analogous approach wave functions the generalized particle are examined in presence of external Dirac monopole field. It is shown that there exists one special state with minimal conserved quantum number j_{min}. It this solution, first, the polarizability ...
Normal state nuclear magnetic resonance studies of the La_3In, La_3Tl compounds have been made in order to investigate the origin of the large temperature-dependent magnetic susceptibility. It is possible to analyse the different contributions to the susceptibility using Knight-shift and relaxation time T_1 measurements of In"1"1"5 and Tl"2"0"5 nuclei. The exchange enhancement of the spin-susceptibility chisub(pd) is of the same order as that found in A-15 compounds and the strong temperature-dependence of chi(T) is attributed to the presence of a peak in the electronic density of states near the Fermi level. The variation of the Knight-shift in the ternary alloys La_3Xsub(1-y)Xsub(y)sup(') is analogous to that observed in the corresponding La_3X phases, on the other hand the Knight-shift in the carbides La_3XC is temperature independent. (author).
We present a description of nuclear spontaneous fission, and generally of quantum tunneling, in terms of instantons - periodic imaginary-time solutions to time-dependent mean-field equations - that allows for a comparison with more familiar and used generator coordinate (GCM) and adiabatic time-dependent Hartree-Fock (ATDHF) methods. It is shown that the action functional whose value for the instanton is the quasiclassical estimate of the decay exponent fulfils the minimum principle when additional constraints are imposed on trial fission paths. In analogy with mechanics, these are conditions of energy conservation and the velocity-momentum relations. In the adiabatic limit the instanton method reduces to the time-odd ATDHF equation, with collective mass including the time-odd Thouless-Valatin term, while the GCM mass completely ignores velocity-momentum relations. This implies that GCM inertia generally overestimates instanton-related decay rate. The very ...
Point contact Josephson junctions can function as millimeter wave heterodyne mixers with conversion gain. The best results achieved thus far show a single sideband conversion gain of 1.3 and a mixer contribution to the system noise temperature of 54"0K. Both of these results are approximately 5 times better than the best published figures for cooled Schottky barrier diode mixers operated at the same frequency. The measured noise for a variety of junctions can be expressed as a universal function of the normalized rf frequency #OMEGA# = h#omega#/2eI/sub c/R. It is about a factor 2 larger than the calculated noise arising from the thermal noise in the junction shunt resistance, R. The noise calculation was done for the resistively shunted junction model using an analog junction simulator.
Studies addressed to a deep understanding of the structure/property relationship on the near infrared (NIR)-emissive erbium-quinolinolate complexes, which are of interest for low-cost photonic systems, are reviewed. The role of the 8-quinolinolate ligand (Q), which studies also as sensitizer to overcome the weak absorptivity of lanthanide ion, is discussed. Synthetic and structural aspects are reported to revise the old assumption that these complexes are analogous in structure to AlQ3 and to point out the specificity of the lanthanide coordination chemistry. In fact depending on reaction conditions, species with high coordination numbers and differing for nuclearity and stoichiometry have been isolated and fully characterized. In some instances it has been shown that coordinated water mol...
The measurement of local heat transfer coefficients is necessary to record the basic phenomena of heat transfer in thin-film apparatuses. For this reason the so-called electrochemical analogy method was developed and used for this application. The electrochemical method implies a specifically composed electrolyte which substitutes the fluid to be evaporated in the thin-film apparatus. Using the redox electrolyte (0,025 kmol/m/sup 3/ K/sub 4/Fe(CN)/sub 6/ resp. k/sub 4/Fe(CN)/sub 6/ and 2nNaOH) the viscosity was, for the first time, thickened until 0.4 Pa s by the help of hydroxyethyl-cellulose.
1,3-Dienes derived from steroidal D-ring C17-ketones undergo Ni(II)-catalyzed hydrovinylation to give 1,2- or 1,4-addition of ethylene. Using finely tuned phosphoramidite ligands it is possible to synthesize either the C20 (R)- or the C20 (S)-derivatives without mutual contamination. The proportion of the 1,4-adduct, which is also formed stereoselectively, can be minimized by optimizing the reaction conditions. Since the two alkenes in the resultant dienes have differing steric demands for many potential reactions, and are ideally juxtaposed for further D-ring functionalization, these intermediates could be useful for the preparation of biologically important compounds such as vitamin D analogs and various antitumor steroidal glycosides.
Background Identifying susceptibility genes for endophenotypes by studying analogous behaviors across species is an important strategy for understanding the pathophysiology underlying psychiatric disorders. This approach provides novel biological pathways plus validated animal models critical for selective drug development. One such endophenotype is avoidance behavior. Methods In the present study, novel automated registration methods for longitudinal behavioral assessment in home cages are used to screen a panel of recently generated mouse chromosome substitution strains that are very powerful in quantitative trait loci (QTL) detection of complex traits. In this way, we identified chromosomes regulating avoidance behavior (increased sheltering preference) independent of motor activity lev...
By analogy with the concepts of human learning, we show and introduce a new method to obtain least product cost and price that includes the effect of innovation and technological learning in manufacturing and production. This key result is a new paradigm instead of the usual economic 'power law' formulation. The new analysis is based on extensive analysis of many technological systems, and is directly related to the presence of learning as experience is accumulated. The results agree with the observed data. By using a consistent basis, the method replaces previous empirical 'power law' descriptions of the technological learning curve with a new 'marginal minimum cost equation' (MCE). (author)
Histone deacetylase (HDAC) inhibitors have been actively exploited as potential anticancer agents. To identify gene targets of HDAC inhibitors, we found that HDAC inhibitors such as sodium butyrate, scriptaid, apicidin and oxamflatin induced the expression of 15-hydroxyprostaglandin dehydrogenase (15-PGDH), a potential cyclooxygenase-2 (COX-2) antagonist and tumor suppressor, in a time and concentration dependent manner in A549 and H1435 lung adenocarcinoma cells. Detailed analyses indicated that HDAC inhibitors activated the 15-PGDH promoter-luciferase reporter construct in transfected A549 cells. A representative HDAC inhibitor, scriptaid, and its negative structural analog control, nullscript, were further evaluated at the chromatin level. Scriptaid but not nullscript induced a signific...
Entorhinal grid cells in mammals fire as a function of animal location, with spatially periodic response patterns. This nonlocal periodic representation of location, a local variable, is unlike other neural codes. There is no theoretical explanation for why such a code should exist. We examined how accurately the grid code with noisy neurons allows an ideal observer to estimate location and found this code to be a previously unknown type of population code with unprecedented robustness to noise. In particular, the representational accuracy attained by grid cells over the coding range was in a qualitatively different class from what is possible with observed sensory and motor population codes. We found that a simple neural network can effectively correct the grid code. To the best of our kn...
The main topic of this thesis concerns efficient algorithms for the calculation of determinants of the kind of matrix typically encountered in lattice QCD. In particular an efficient method for calculating the fermion determinant is described. Such a calculation is useful to illustrate the effects of light dynamical (virtual) quarks. The methods employed in this thesis are stochastic methods, based on the Lanczos algorithm, which is used for the solution of large, sparse matrix problems via a partial tridiagonalisation of the matrix. Here an implementation is explored which requires less exhaustive treatment of the matrix than previous Lanczos methods. This technique exploits the analogy between the Lanczos tridiagonalisation algorithm and Gaussian quadrature in order to calculate the fermion determinant. A technique for determining a number of the eigenvalues of the matrix is also presented. A demonstration is then given of how one can improve upon this estimate ...
A major deficiency of current photon calculation methods that are based on the concept of primary and scatter separation is their inability to handle the condition of electronic disequilibrium. This deficiency is examined and it is shown that the limitation is not inherent in the algorithms themselves but is, at least in part, in the data which the algorithms use. A new concept of primary and scatter separation is developed to cover the condition of electronic disequilibrium. This new concept requires little change to the existing algorithms and only additional data are required, which are generated using Monte Carlo calculation methods. The new concept is tested using programs in the Theratronics Theraplan treatment-planning system, and two calculation examples illustrate the ability to model electron transport and also the improvement over the existing algorithms. Close analogy of the extended concept with the convolution/superposition method of dose calculation ...
The electronic structures of BaSnO_3, BaSbO_3, and BaPbO_3, calculated using an extended general-potential linearized augmented-plane-wave method, are reported. The electronic structures of BaSnO_3 and its 6s analog BaPbO_3 are found to be very different, explaining the absence of superconductivity in the Ba(Sn,Sb)O_3 system. These differences are explained by a combination of the relativistic lowering of the 6s states and ion-size effects. Muffin-tin-approximation augmented-plane-wave calculations for BaSnO_3 are also reported and the utility of the muffin-tin approximation for this and similar materials is discussed in terms of the differences between the two sets of calculations.
As a general approach to the problem of precursive behavior in alloys that undergo a displacive transformation, defect theories are becoming increasingly popular. However, the microscopic origin of the proposed defects is usually not considered. Yu and Anderson (1984) have argued that properties of strong-coupling superconductors, such as the A-15 compounds, imply a breakdown of Migdal's theorem (the adiabatic, or Born-Oppenheimer approximation for separation of electrons and phonons) in these systems. The electron-phonon coupling is so strong that it must be incorporated already in zeroth order. This is the basis for local phonon models, in which the electron-phonon coupling provides an effective double well potential for a localized group of atoms. The Yu-Anderson model and an analogous local Jahn-Teller model (Abell, 1983) are reviewed in connection with displacive transformations in strong-coupling alloys.
We investigate the effect of the intrinsic spin of a fundamental spinor field on the surrounding spacetime geometry. We show that despite the lack of a rotating stress-energy source (and despite claims to the contrary) the intrinsic spin of a spin-half fermion gives rise to a frame-dragging effect analogous to that of orbital angular momentum, even in Einstein-Hilbert gravity where torsion is constrained to be zero. This resolves a paradox regarding the counter-force needed to restore Newton's third law in the well known spin-orbit interaction. In addition, the frame-dragging effect gives rise to a {\\it long-range} gravitationally mediated spin-spin dipole interaction coupling the {\\it internal} spins of two sources. We argue that despite the weakness of the interaction, the spin-spin interaction will dominate over the ordinary inverse square Newtonian interaction in any process of sufficiently high-energy for quantum field theoretical effects to be ...
A transformation monoid on a set Omega is called synchronizing if it contains an element of rank 1 (that is, mapping the whole of Omega to a single point). In this paper, I tackle the question: given n and k, what is the probability that the submonoid of the full transformation monoid T_n generated by k random transformations is synchronizing? This question is analogous to Dixon's Theorem that two random permutations generate the symmetric or alternating group with high probability. Following the technique of Dixon's theorem, we need to analyse the maximal non-synchronizing submonoids of T_n. I develop a very close connection between transformation monoids and graphs, from which we obtain a description of non-synchronizing monoids as endomorphism monoids of graphs satisfying some very strong conditions. However, counting such graphs, and dealing with the intersections of their endomorphism monoids, seems difficult.
A comparison is made of the response of a count ratemeter and a pulse counter using the mathematical tool of the Z transform. Transform Z is used for the solution of the convolution integral interpreting the analog output of the count ratemeter used for recording characteristic radiation, excited in the moving beam. The comparison of count rates obtained by the count ratemeter during continuous analysis and the pulse counter during discontinuous measurement gave the transfer function of the count ratemeter in the actual range of count rate. Also discussed is the use of the transfer function for localizing concentration changes in the sample. The use of the described method is demonstrated on the determination of the tin content in tungsten using continuous radionuclide X-ray fluorescence analysis. (B.S.).
In order to suppress resonance vibrations of a rotor-shaft of rotating machinery, a rotor-shaft system elastically supported by ball bearings which are installed in electromagnetic actuators are proposed and the design method of some compensatory circuits in the controller to control the electromagnetic actuators in the system are explained. These actuators are controlled by the analog PID (proportional, integral, and derivative) controller. The compensation for nonlinearity of electromagnetic force, the negative stiffness of electromagnet, and the time lag of the coil current are discussed and the effective control circuits are proposed. The rotor-shaft system is replaced by the equivalent two-degree-of-freedom system and both impulse and frequency responses are numerically simulated for several parameters of PD-controller gain. By applying the principle of dynamic absorbers, optimum parameters are calculated. The gains of the control circuit are adjusted to give ...
A deep band of {l_brace}311{r_brace} defects was created 520 nm below the silicon surface with a 350 keV Si implant followed by a cluster-forming rapid thermal anneal (800 C, 1000 s). Chemical etching was used to vary the depth to the surface of the {l_brace}311{r_brace}-defect band. Afterwards, the defect dissolution was investigated at 750 C for different times. Varying the depth in this fashion assures that only the depth and no other feature of the cluster distribution is changed. The {l_brace}311{r_brace} defects were analyzed by plan-view, transmission electron microscopy. We show that the dissolution time of the {l_brace}311{r_brace}-defect band varies linearly with depth, confirming that surface recombination controls the dissolution and is consistent with analogous observations of transient enhanced diffusion.
A deep band of #left brace#311#right brace# defects was created 520 nm below the silicon surface with a 350 keV Si implant followed by a cluster-forming rapid thermal anneal (800 C, 1000 s). Chemical etching was used to vary the depth to the surface of the #left brace#311#right brace#-defect band. Afterwards, the defect dissolution was investigated at 750 C for different times. Varying the depth in this fashion assures that only the depth and no other feature of the cluster distribution is changed. The #left brace#311#right brace# defects were analyzed by plan-view, transmission electron microscopy. We show that the dissolution time of the #left brace#311#right brace#-defect band varies linearly with depth, confirming that surface recombination controls the dissolution and is consistent with analogous observations of transient enhanced diffusion.
We have constructed a mathematical model that describes the coherent spontaneous radiation of a macroscopically filled exciton mode. We have demonstrated qualitatively ways in which a coherent subsystem of excitons can be formed. When this occurs under the influence of an external coherent source, exciton free induction occurs, while in the case of a spontaneous transition of the excitons to a coherent state through freezing of the reservoir of intermolecular interactions superradiance occurs. We have concluded that superradiance in the system of Frenkel excitons is possible under the influence of the non-Dicke mechanisms of self-induction of correlations, when the dipole transition moments of the individual atoms are coupled into a single macroscopic effective spin through their electrostatic interaction, this being analogous to the ordering of magnetic dipole moments in a ferromagnet.
A nonlinear free boundary-value problem of supercavitating flow past n + 1 hydrofoils is analyzed. To describe the cavities' closure mechanism, the Tulin-Terentev single-spiral-vortex model is employed. The flow domain is considered as the image of an (n + 1)-connected circular domain. The conformal map is constructed in terms of the solutions to two Riemann-Hilbert problems of the theory of symmetric automorphic functions. One of the problems is homogeneous and its coefficients are continuous functions while the second problem is inhomogeneous and has discontinuous coefficients. The exact solutions to the problems are found by using quasiautomorphic and quasimultiplicative analogs of the Cauchy kernel. The case of a single plate is considered in detail and the numerical results are report...
We study the behavior of the Chern classes of graph hypersurfaces under the operation of deletion-contraction of an edge of the corresponding graph. We obtain an explicit formula when the edge satisfies two technical conditions, and prove that both these conditions hold when the edge is multiple in the graph. This leads to recursions for the Chern classes of graph hypersurfaces for graphs obtained by adding parallel edges to a given (regular) edge. Analogous results for the case of Grothendieck classes of graph hypersurfaces were obtained in previous work. Both Grothendieck classes and Chern classes were used to define `algebro-geometric' Feynman rules. The results in this paper provide further evidence that the polynomial Feynman rule defined in terms of the Chern-Schwartz-MacPherson class of a graph hypersurface reflects closely the combinatorics of the corresponding graph. The key to the proof of the main result is a more general formula for the ...
As the number of devices is increasing in centralized monitoring and control rooms, Ashibetsu Mine of Mitsui Coal Mining Co. has carried out a study on the installation of a computer system for labor savings in the analysis and judgment of operators and for quick and accurate response for emergency in 1984. The target of the first stage was set to centralized monitoring of analog and on-off data using computers. The development plan included: the development of the first stage system of their mine based on the (A/D) 104 connected points and review of problems in 1985: and extension of equipment and revision of the entire system in 1986. The most favorable effect of the system installation is that effective monitoring is possible with display and that the data stored in the computer can be used later. (8 figs, 1 ref)
We have studied the vibrational properties of the filled tetrahedral semiconductor LiMgAs and its binary analog AlAs by using the plane-wave pseudopotential method within density functional theory. The calculated lattice constants for the studied compounds are in good agreement with previous theoretical and experimental results. The phonon dispersion curves and phonon density of states are calculated by using density functional perturbation theory. The sound speeds in different directions are quantitatively similar in LiMgAs and AlAs. The assignment of the zone center modes to the relative motion of the atoms shows that the lower optic modes are due to the Mg-As pair vibrations, while for the upper ones the Li-Mg pair dominates, which is attributed to the smaller Mg atom mass. The longitudinal interatomic force constant of Mg-As is about 66% higher than that of Li-As, showing the relatively high covalency of the former bond.
Pulse reactor experiments were conducted on the reactions of unlabeled or deuterium- or oxygen-18-labeled allyl alcohols over molybdenum trioxide and various bismuth molybdates in the absence or presence of oxygen and ammonia. The allyl alcohol apparently adsorbed on oxidation sites to form acrolein via allyl molybdates, and on Broensted acid sites to form diallyl ether via an allyl carbonium ion. The bismuth enhanced ..cap alpha..-hydrogen abstraction, which was the rate-determining step in the oxidation. The product distributions provided evidence that the selective oxidation of propylene to acrolein proceeds via a m-allyl molybdate which collapses to an O o-allyl molybdate prior to the second hydrogen abstraction, and that the analogous N o-complex in ammoxidation undergoes two hydrogen abstractions to form acrylonitrile. Detailed reaction schemes are developed.
A simple and efficient method for characterization of multidimensional Gaussian states is suggested and experimentally demonstrated. Our scheme shows analogies with tomography of finite dimensional quantum states, with the covariance matrix playing the role of the density matrix and homodyne detection providing Stern-Gerlach-like projections. The major difference stems from a different character of relevant noises: while the statistics of Stern-Gerlach-like measurements is governed by binomial statistics, the detection of quadrature variances correspond to chi-square statistics. For Gaussian and near Gaussian states the suggested method provides, compared to standard tomography techniques, more stable and reliable reconstructions. In addition, by putting together reconstruction methods for Gaussian and arbitrary states, we obtain a tool to detect the non-Gaussian character of optical signals.
The interscalenic block technique is widely used for ambulatory shoulder surgery despite a substantial number of failures and adverse effects. We prospectively evaluated satisfaction in 40 consecutive patients who underwent open Bankart repair under a single general anesthesic performed in an ambulatory care unit. The mean age of the patients was 23 years. There were 29 men and 11 women. Patients were evaluated postoperatively with a visual analog scale of pain (in the recovery room, at the time of discharge, and the day after and 1 week after surgery) via a home assessment questionnaire that included the following: effectiveness of oral pain medication, ability to perform activities of daily life, and overall satisfaction. One patient failed to be discharged because of a feeling of faintn...
Readout integrated circuits (ROICs) for focal plane arrays (FPAs) have become increasingly complex to meet the needs of modern infrared systems. BAE Systems has pioneered a number of advanced signal processing architectures for FPA ROICs. Demonstrated signal processing capabilities of BAE Systems FPAs include analog-to-digital conversion, offset subtraction, individual pixel automatic gain compensation, transient noise suppression, on-FPA defect deselection, reconfigurable pixels, spatial neural network processing and subframe noise averaging. BAE Systems FPA advanced signal processing is not just for demonstrations, but is used in many of their deliverable FPAs, improving real system performance.
The absorption of carbonyl sulfide in aqueous methyldiethanolamine (MDEA) was studied over a range of temperatures and MDEA concentrations. MDEA is commonly used for selective absorption of hydrogen sulfide in the presence of carbon dioxide. However, sulfur in the form of COS may also be present and it is necessary that estimates of absorption rates of this compound be made. The objective of this study is to determine the physiochemical properties needed to predict COS absorption rates in aqueous MDEA. Free gas solubility and the diffusivity of COS in MDEA solutions were measured over the temperature range 15 to 40{sup 0}C for MDEA concentrations up to 30 weight per cent using the nitrous oxide analogy method. Solubilities were measured volumetrically in an equilibrium cell and diffusivities were measured using a laminar liquid jet absorber. The kinetics of the reaction between COS and MDEA were studied by measuring absorption rates in a single wetted-sphere ...
In two recent papers, we constructed a new N#->##infinity# limit of the W_N algebras, which we denote W_#infinity# having generators of conformal spins 2, 3, ..., with central terms for all spins. In this paper, we construct another new algebra, which we denote W_1_+_#infinity#, with generators of conformal spins, 1, 2, 3, ..., again with central terms for all spins. The requirement that the algebras be closed requires that one include the spin-1 generators in W_1_+_#infinity#, and prohibits their inclusion in W_#infinity#. Paralleling our analogous construction for W_#infinity#, we show that the new algebra can also be realised as the antisymmetric part of an associative 'lone-star' product, which also closes on the set of generators with conformal spins #>=#1. (orig.).
An observational cohort study was conducted to compare the performance of the RIFLE (risk, injury, failure, loss and end-stage kidney disease), AKIN (acute kidney injury network) and conventional graded criteria to identify acute kidney injury (AKI) following SCT and to predict long-term mortality in 141 myeloablative allogeneic SCT (m-allo), 60 non-myeloablative allogeneic SCT (nm-allo) and 48 autologous SCT (auto) cases. The AKIN criteria had less ability to identify patients as having the lowest category, stage 1 (analogous to RIFLE risk): 33% (37%) in m-allo, 23% (32%) in nm-allo and 8.3% (16.7%) in auto. Cox regression showed that categories higher than the intermediate stage were independent predictors of mortality in all three definitions. The areas under receiver operating characte...
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...
The Large Hadron Collider presents an unprecedented opportunity to probe the realm of new physics in the TeV region and shed light on some of the core unresolved issues of particle physics. These include the nature of electroweak symmetry breaking, the origin of mass, the possible constituent of cold dark matter, new sources of CP violation needed to explain the baryon excess in the universe, the possible existence of extra gauge groups and extra matter, and importantly the path Nature chooses to resolve the hierarchy problem - is it supersymmetry or extra dimensions. Many models of new physics beyond the standard model contain a hidden sector which can be probed at the LHC. Additionally, the LHC will be a top factory and accurate measurements of the properties of the top and its rare decays will provide a window to new physics. Further, the LHC could shed light on the origin of neutralino masses if the ...
Atomic Energy Regulatory Board carries out the regulatory review of the reactor physics design, commissioning and operational aspects through Project Design Safety Committee and Specialist Group of reactor physicists with wide experience in the design, commissioning and operational safety review of NPPs. TAPP-3 and 4 PHWRs, being the first indigenous design of 540 MWe Units, are quite different than the standard 220 MWe PHWRs. The safety review of reactor physics design was quite complex, as majority of the systems were new. The Reactor Physics Specialist Group carried out extensive safety review of 540 MWe PHWR reactor physics design and made significant contributions of design modifications and improvements in the operational procedures. Some salient contributions include: Monitoring the core during bulk addition of moderator without the availability of shutdown systems. Logics for providing safety ...
Recent studies in elementary particle physics have made the need for an e{sup +}e{sup -} linear collider able to reach energies of 500 GeV and above with high luminosity more compelling than ever [1]. Observations and measurements completed in the last five years at the SLC (SLAC), LEP (CERN), and the Tevatron (FNAL) can be explained only by the existence of at least one particle or interaction that has not yet been directly observed in experiment. The Higgs boson of the Standard Model could be that particle. The data point strongly to a mass for the Higgs boson that is just beyond the reach of existing colliders. This brings great urgency and excitement to the potential for discovery at the upgraded Tevatron early in this decade, and almost assures that later experiments at the LHC will find new physics. But the next generation of experiments to be mounted by the world-wide particle physics community must not only find ...
BackgroundXMRV (xenotropic murine leukemia virus-related virus) is the first known example of an exogenous gammaretrovirus that can infect humans. A limited number of reports suggest that XMRV is intrinsically resistant to many of the antiretroviral drugs used to treat HIV-1 infection, but is sensitive to a small subset of these inhibitors. In the present study, we used a novel marker transfer assay to directly compare the antiviral drug sensitivities of XMRV and HIV-1 under identical conditions in the same host cell type.ResultsWe extend the findings of previous studies by showing that, in addition to AZT and tenofovir, XMRV and HIV-1 are equally sensitive to AZddA (3'-azido-2',3'-dideoxyadenosine), AZddG (3'-azido-2',3'-dideoxyguanosine) and adefovir. These results indicate that specific 3'-azido or acyclic nucleoside analog inhibitors of HIV-1 reverse transcriptase (RT) also block XMRV infection with comparable efficacy in vitro. Our data confirm that XMRV is ...
Calcium-activated chloride channels (CaCCs) are widely expressed in mammalian tissues, including intestinal epithelia, where they facilitate fluid secretion. Potent, selective CaCC inhibitors have not been available. We established a high-throughput screen for identification of inhibitors of a human intestinal CaCC based on inhibition of ATP/carbachol-stimulated iodide influx in HT-29 cells after lentiviral infection with the yellow fluorescent halide-sensing protein YFP-H148Q/I152L. Screening of 50,000 diverse, drug-like compounds yielded six classes of putative CaCC inhibitors, two of which, 3-acyl-2-aminothiophenes and 5-aryl-2-aminothiazoles, inhibited by >95% iodide influx in HT-29 cells in response to multiple calcium-elevating agonists, including thapsigargin, without inhibition of calcium elevation, calcium-calmodulin kinase II activation, or cystic fibrosis transmembrane conductance regulator chloride channels. These compounds also inhibited calcium-dependent chloride ...
The natriuretic peptides are considered to be cardioprotective; however, their receptors have not been identified in human myocardium using radiolabeled analogs. Dendroaspis natriuretic peptide (DNP) has been recently identified as a new member of this peptide family and is thought to be less susceptible to enzymatic degradation. Therefore, we have developed the novel radiolabeled analog [125I]-DNP and used this to localize high-affinity (K(D)=0.2 nmol/L), saturable, specific binding sites in adult human heart (n=6) and coronary artery (n=8). In competition binding experiments, atrial natriuretic peptide and brain type natriuretic peptide had greater affinity for [125I]-DNP binding sites than C-type natriuretic peptide and the natriuretic peptide receptor (NPR)-C ligand, cANF. This rank order of potency suggested binding of [125I]-DNP was specific to NPR-A. Messenger RNA encoding NPR-A was identified in left ventricle and coronary artery smooth ...
An attempt is taken to explain anomalies in "9"2Mo(d, n)"9"3Tc, "9"2Mo(d, #alpha#)"9"0Nb, "9"4Mo(d, n)"9"5Tc, "9"8Mo(d, n)"9"9Tc, "9"8Mo(d, p)"9"9Mo, "9"8Mo(d, #alpha#)"9"6Nb, "1"0"0Mo(d, p)"1"0"1Mo and "1"0"0Mo(d, n)"1"0"1Tc reactions with input states having a one-particle nature. Thin films saturated with molybdenum isotopes at the approximately 1 mgxcm"-"2 surface density are used as targets. The targets are irradiated by the extracted cyclotron beam. The deuteron energy is 5-12 MeV. The reaction cross sections are determined by the activation analysis method. Quasi-stationary levels of the nucleus-deuteron system are calculated. Weak anomalies revealing in a smooth (d, #alpha#) reaction cross section on sup(92, 98)Mo nuclei, which do not necessarily correlate with anomalies in the (d, n) and (d, p) channels, are observed. The ground states of the (d, #alpha#) reaction products "9"0Nb and "9"6Nb have (8"+) and (6"+) spins, respec,.ively, that testifies to a considerable ...
Basalt and diabase from the Cretaceous Dumisseau Formation, southern Haiti have Mg-numbers of 43-63, TiO/sub 2/ contents of 1.6-3.9% and La abundances of 3.6-15.3 ppm. LaTa ratios average 10, and indicate that the basalts are oceanic in character, distinct from the arc associations forming the northern part of Haiti. Oldest lavas have low TiO/sub 2/, (1.6%) and are LREE-depleted, similar to N-MORBs, whereas overlying lavas have higher TiO/sub 2/ (2-3.9%) and are LREE-enriched, similar to E-MORBs or hotspot basalts. /sup 87/Sr/sup 86/Sr ratios vary from 0.70280 to 0.70316, /sup 143/Nd/sup 144/Nd from 0.512929 to 0.513121, and /sup 206/Pb/sup 204/Pb from 19.00 to 19.27 LREE-depleted lavas have high /sup 143/Nd/sup 144/Nd (0.51309-0.51310) typical of MORBs, whereas /sup 143/Nd/sup 144/Nd in the LREE-enriched lavas varies widely (0.512929-0.513121). Chemical features of the Dumisseau basalts are equivalent to those of Caribbean seafloor basalts recovered on DSDP Leg 15, and support the ...
Extracellular ATP stimulates transmembrane ion fluxes in the mouse macrophage cell line J774. In the presence of Mg2+, nonhydrolyzable ATP analogs and other purine and pyrimidine nucleotides do not elicit this response, suggesting the presence of a specific receptor for ATP on the macrophage plasma membrane. One candidate for such a receptor is the ecto-ATPase expressed on these cells. We, therefore, investigated the role of this enzyme in ATP-induced /sup 86/Rb+ efflux in J774 cells. The ecto-ATPase had a broad nucleotide specificity and did not hydrolyze extracellular ATP in the absence of divalent cations. /sup 86/Rb+ efflux was not blocked by inhibition of the ecto-ATPase and did not require Ca2+ or Mg2+. In fact, ATP-stimulated /sup 86/Rb+ efflux was inhibited by Mg2+ and correlated with the availability of ATP4- in the medium. In the absence of divalent cations, the slowly hydrolyzable ATP analogs adenosine 5'-(beta, ...
Several signatures of new physics accessible at the LHC either suffer from top-quark production as a significant background or contain top quarks themselves. In this talk, we present results on top quark physics obtained from the first LHC data collected by the CMS experiment.They include measurements of the top pair production cross section in various channels and their combination, measurements of the top quark mass, the single top cross section, a search for new particles decaying into top pairs, and a first look at the charge asymmetry.
Physicists are no strangers to Feynman diagrams, but the meaning of the diagrams is not always clear, even to those who have used them. That confusion has deep roots, as Kaiser clearly and convincingly explains. To Feynman himself, a diagram depicted an actual physical process in space-time, such as the exchange of photons that occurs when an electron and proton collide. However, he also saw it as shorthand for the contributions to the amplitude of a physical process made by the element of the process it depicted. The best part of this new book covers the early history, social history and 'conceptual history' of Feynman diagrams. Disagreements and criticisms aside, the book will be invaluable to historians and sociologists of physics interested in the growth of Feynman diagrams. (U.K.)
The Office of Civilian Radioactive Waste Management (OCRWM) is executing a plan for improvement of the United States Nuclear Waste Management Program. As part of the plan, OCRWM is performing a systems engineering analysis of both the physical system, i.e., the Nuclear Waste Management System (NWMS), and the programmatic functions that must be accomplished to bring the physical system into being. The functional analysis effort is being performed by two separate teams working in parallel, one of which addresses the physical system functions and the other the programmatic functions. This paper presents information on the analysis of the programmatic functions.
The present paper investigates the peristaltic transport of a couple stress fluid in an asymmetric channel with the effect of the induced magnetic field. The exact solutions of momentum and the magnetic field equations have been calculated under the assumptions of long wave length and low but finite Reynolds number. The expression for pressure rise has been computed numerically using mathematics software Mathematica. The graphical results have been presented to discuss the physical behavior of various physical parameters of interest. Finally, the trapping phenomena have been discussed for various physical parameters. (orig.)
The present paper investigates the peristaltic transport of a couple stress fluid in an asymmetric channel with the effect of the induced magnetic field. The exact solutions of momentum and the magnetic field equations have been calculated under the assumptions of long wave length and low but finite Reynolds number. The expression for pressure rise has been computed numerically using mathematics software Mathematica. The graphical results have been presented to discuss the physical behavior of various physical parameters of interest. Finally, the trapping phenomena have been discussed for various physical parameters.
...225J Einstein, Oppenheimer, Feynman: Physics in the 20th Century Fall 2002 8.231 Physics of Solids I Fall 2002 8.251 String Theory for Undergraduates Spring 2003 8.261J Introduction to Computational Neuroscience Spring 2002 8.282J Introduction to Astronomy Spring 2003 8.321 Quantum Theory I Fall 2002 8.322 Quantum Theory II Spring 2003 8.323 Relativistic Quantum Field Theory I Spring 2003 8.324 Quantum Field Theory II ...
Having always been at the forefront of information management and open access, High-Energy Physics (HEP) proves to be an ideal test-bed for innovations in scholarly communication including new information and communication technologies. Three selected topics of scholarly communication in High-Energy Physics are presented here: A new open access business model, SCOAP3, a world-wide sponsoring consortium for peer-reviewed HEP literature; the design, development and deployment of an e-infrastructure for information management; and the emerging debate on long-term preservation, re-use and (open) access to HEP data.
Gamete development requires a coordinated soma-germ line interaction that ensures renewal and differentiation of germline and somatic stem cells. The physical contact between the germline and somatic...Full Text Available
... of Hanoi or Missionaries and Cannibals, It is not immediately obvious what constitutes a "move"--that is, what actual manipulations of the physical ...
Violence in both community and county hospitals in the USA is increasing. It caused significant physical, emotional and economic hardship to many emergency department employees. We describe an incident...Full Text Available
The protocols presently established for optimum seed storage do not account for the chemical composition of different seed species, the physiological status of the seed, and the physical status of water...Full Text Available
We obtain conformal invariant topological field theories with N = 2 supersymmetry by twisting Sevrin, Troost and Van Proeyen's SU(2) x SU(2) x U(1) extended N = 4 superconformal field theories. We expect that the number of physical states is finite although the original N = 4 theories have continuous spectra. It is shown that the number of physical states is actually finite when the central charge c < 6 in the corresponding N = 4 theories. The physical states inherit the structure of the chiral ring in N = 2 superconformal minimal series which is obtained by the reduction from N = 4 theories. We also show that the algebra contains the topological N = 4 superconformal algebra as subalgebra. Therefore a closed set of a finite number of physical states in the topological N = 1 superconformal algebra can also be obtained. (orig.).
Abstract Normal human aging is accompanied by progressive brain tissue loss and cognitive decline; however, several factors are thought to influence brain aging. We applied tensor-based morphometry to high-resolution brain MRI scans to determine whether educational level or physical activity was associated with brain tissue volumes in the elderly, particularly in regions susceptible to age-related atrophy. We mapped the 3D profile of brain volume differences in 226 healthy elderly subjects (130F/96M; 77.9 3.6 SD years) from the Cardiovascular Health Study-Cognition Study. Statistical maps revealed the 3D profile of brain regions whose volumes were associated with educational level and physical activity (based on leisure-time energy expenditure). After controlling for age, sex, and physical...
The product-operator formalism is the most commonly used tool for describing and designing multidimensional NMR experiments. In spite of its relative simplicity and sound theoretical underpinnings,...Full Text Available
AbstractMicrobial capsules are important for virulence, but their architecture and physical properties are poorly understood. The human pathogenic fungus Cryptococcus neoformans...Full Text Available
We present results on searches for exotic particles (relativistic magnetic monopoles and WIMPs) and for UHE neutrinos, obtained with the Baikal neutrino telescope NT200.
Education resources dealing with solar-terrestrial physics, solar effects, solar radiation, etc. Includes links to short reference papers on subjects ... ...
This Chapter develops a realist information-theoretic interpretation of the nonclassical features of quantum probabilities. On this view, what is fundamental in the transition from classical to quantum physics is the recognition that \\emph{information in the physical sense has new structural features}, just as the transition from classical to relativistic physics rests on the recognition that space-time is structurally different than we thought. Hilbert space, the event space of quantum systems, is interpreted as a kinematic (i.e., pre-dynamic) framework for an indeterministic physics, in the sense that the geometric structure of Hilbert space imposes objective probabilistic or information-theoretic constraints on correlations between events, just as the geometric structure of Minkowski space in special relativity imposes spatio-temporal kinematic constraints on events. The interpretation of quantum ...
This paper reviews the historical aspects of nuclear physics. The scientific aspects of the early transuranium elements are discussed and arms control measures are reviewed. 11 refs., 14 figs. (LSP)
Statistical fluctuations limit the precision with which a microorganism can, in a given time T, determine the concentration of a chemoattractant in the surrounding medium. The best a cell can do is...Full Text Available
This study aimed to explore the impact of perceived service quality and self-concept on consumer attitude and purchase process using channel type (physical and Internet) as a segmentation variable. From the perspective of consumer behaviour, this study attempted to estimate a relational model and perform an empirical validation using female cosmetics and skincare products as an example. It was discovered that the influence of perceived service quality and self-concept on consumer attitude, purchase intention and behaviour, satisfaction, and loyalty varied with channel type. The analysis result revealed that physical stores presented higher levels of agreement with all research perspectives than Internet stores. However, only two relational paths have a higher influencing effect in physical...
... Society Physics Press Release 05-175Korea Joins International Computing Infrastructure ... connectivity with Korea in a ceremony last month. Facilitated by the Korea Institute for Science and ...
The inflexibility of double-stranded DNA with respect to bending and twisting is well established in vitro. Understanding apparent DNA physical properties in vivo is...Full Text Available
ObjectiveTo evaluate the effect of moderate aerobic physical activity in water on fetal cardiotocography patterns in sedentary pregnant women.MethodIn...Full Text Available
The authors present some recent measurements on electroweak physics using data collected by the CDF experiment at the Tevatron proton anti-proton collider ({radical}s = 1.96 TeV) at Fermilab.
Cutaneous scarring can cause patients symptoms ranging from the psychological to physical pain. Although the process of normal scarring is well described the ultimate cause of pathological scarring...Full Text Available