cssi/SciSciGPT-SciSciNet huggingface dataset:
Convolutional Codes and Finite Interleavers for the Block Erasure Channel

In this paper we analyze a simple model which attempts to describe the transmission of convolutionally encoded data over channels with memory using finite interleaving. The model could for example describe the performance of a slow frequency hopping system in which every frequency is either totally blocked or else noiseless, and in which interleaving depth is limited by the maximal delay allowed in the link. For this model, we provide an analytic expression for the Bit Error Rate for periodic bit and word interleavers, as well as for pseudo-random bit and word interleavers. The probability of a message error is also analyzed.
Development of high resolution x -ray spectrometers for the investigation of bioinorganic chemistry in metalloproteins

Metals play as varied a role in biology as the proteins they are part of. They are involved in structure formation, they help transfer material and information, and they catalyze chemical reactions. Other proteins transport material or information, such as hemoglobin that distributes O2 and takes up CO2, or insulin that signals cells to increase glucose uptake in response to high blood glucose levels. Again other proteins promote chemical reactions, such as photosystem II responsible for photosynthetic oxygen evolution or nitrogenase which catalyzes the reduction of N2 to NH3. All of these proteins require the presence of a metal ion for their activity.
Structural and functional organization of herpes simplex virus DNA polymerase investigated by limited proteolysis.

The 1235 residue herpes simplex virus DNA polymerase is a prototype alpha-like DNA polymerase and also an antiviral drug target. To investigate its organization, we mapped favored cleavage sites for seven proteases and identified three major classes of stable proteolytic fragments: 70-85-kDa N-terminal fragments, 50-70-kDa fragments that start near residues 600-700, and 12-kDa C-terminal fragments. In coimmunoprecipitation experiments, the first two classes of fragments remained associated; thus, cleavage in the center of the protein did not resolve structurally separate domains. In contrast, the 12-kDa C-terminal fragments did not remain associated with other fragments, suggesting a small separable C-terminal domain. The 70-85-kDa N-terminal fragments contained 3‘-5‘ exonuclease and ribonuclease H activities; however, cleavage at the center of the molecule or near the C terminus appeared to destroy DNA polymerase activity. All three major classes of fragments bound DNA in DNA-cellulose chromatography and Southwestern blot analyses. The C-terminal fragments bound the viral polymerase processivity factor, UL42. The results map activities to regions of herpes simplex virus polymerase and suggest a model for its organization that may be pertinent to other DNA polymerases.
O declínio da soberania ou a emergência de normas cosmopolitanas? Repensando a cidadania em tempos voláteis

This essay examines recent debates concerning the emergence of cosmopolitan norms such as those pertaining to universal human rights, crimes against humanity as well as refugee, immigrant and asylum status. What some see as the spread of a new human rights regime and a new world order others denounce as the “spread of empire” or characterize as “law without a state”. In contrast, by focusing on the relationship of global capitalism to deterritorialized law this essay distinguishes between the spread of human rights norms and deterritorialized legal regimes. Although both cosmopolitan norms and deterritorialized law challenge the nation-state and threaten to escape control by democratic legislatures, it argues that cosmopolitan norms enhance popular sovereignty while many other forms of global law undermine it. It concludes by pleading for a vision of “republican federalism” and “democratic iterations”, which would enhance popular sovereignty by establishing interconnections across the local, the national and the global.
HUMAN RISKY CHOICE ACROSS FOUR PROBABILITY DISTRIBUTIONS

Three adult humans were presented with choices between fixed and variable (probabilistic) numbers of points exchangeable for money. The mean number of points per trial was held constant across fixed and variable outcomes while the form of the distribution of outcomes on the variable option was manipulated. Across conditions, choice was assessed across bivalued, rectangular, reverse exponential, and approximately normal probability distributions. To more closely approximate procedures used with nonhumans, contingencies were experienced directly across repeated trials under steady-state conditions, and potential verbal influences were minimized. Subjects strongly preferred the fixed option across most conditions regardless of distribution type. The results replicate and extend those obtained with humans' choices involving verbal/hypothetical outcomes and with nonhumans' choices involving food reinforcers, and they illustrate a potentially useful procedure for cross-species comparisons in risky choice. Risky choice is typically studied by presenting subjects with choices
More Theory of Modules

In this Chapter, we shall cover some other aspects of the theory of modules that were not yet touched upon in the first two chapters. In contrast to Ch. 1 and Ch. 2, the module theory presented in the three sections of this Chapter is essentially non-homological in nature. Nevertheless, the idea of injective modules and essential extensions plays a discernible role, especially in the first and last sections of the Chapter.
Fundamental Solutions for Differential Operators and Applications

This volume provides a self-contained and systematic development of an aspect of analysis which deals with the theory of fundamental solutions for differential operators, as well as their applications to boundary value problems of mathematical physics, applied mathematics, and engineering. Features of the text include: extensive applications topics presented in detail, with worked examples; coverage of over 70 different differential operators and derivation of fundamental solutions for them by using Fourier transforms and the theory of distributions; computational components discussed in all relevant topics and applications; an appendix describing numerous algorithms, and programs in C to illustrate solutions methods. All computer-based material is available by FTP from the Birkhauser web site.
Comparison of six, four and two-vector formalisms for complex media

Advances in rapid prototyping using conductive-inkjet and 3D printing, for example, have made the fabrication of antennas and artificial complex media possible. These advances have prompted the need for alternative mathematical methods of analysis that are capable of handling anisotropic and bianisotropic media and also aid in better understanding of the physical nature of electromagnetic fields in complex media environments. As an example, a compact six-vector formalism for Maxwell's equations was developed (I.V. Lindell, A.H. Sihvola, and K. Suchy, J. of Electrom. Waves and Appl., 9, 7/8, 887–903, 1995) that aids in the mathematical manipulation and subsequent solution of problems involving complex media. This formulation can accommodate fully populated material tensors (i.e., all material tensor elements are non-zero), however, the analysis leads to a block 3×3 matrix that requires inversion. If the material property tensors of permittivity and permeability have no transverse-longitudinal or longitudinal-transverse components (i.e., the xz, yz, zx, zy elements are zero), then a four-vector approach can be advantageously employed leading to a block 2×2 matrix which is more easily inverted due to the reduced dimensionality compared to the six-vector approach. In addition, a more compact and physically-insightful form is often achieved for this specialized case of material tensors. If, furthermore, the material property tensors are restricted to gyrotropic media, then a two-vector technique can be readily sought that results in a block 1×1 matrix formulation, which substantially simplifies the analysis and leads to enhanced clarity of the physical nature of the electromagnetic fields.
Rare Open Hallux Interphalangeal Joint Dislocations Sustained in Combatives Training: A Case Series

ABSTRACTHallux interphalangeal joint dislocations are a very rare occurrence, and open medial dislocations of the hallux interphalangeal joint, to our knowledge, have not been previously reported in the literature. We report two open medial dislocations, one with fracture, that were sustained within a year of each other at the same military installation. Both patients presented were active duty soldiers that were involved in barefoot combatives and caught their hallux in the fold of the mats while simultaneously experiencing a “twisting force” applied to their foot by their combatives partner. Each soldier required surgical intervention and healed uneventfully, able to return to full activities in an average of 10 weeks with no residual pain. Two injuries of this rarity occurring with the same mechanism of injury within a year at the same military base raise concerns about the surface and shoegear being used for combatives training. The initial analysis of these two separate but similar cases points to th...
Quantifying gravel overlap and dislodgement forces on natural river bars: implications for particle entrainment

Equations for predicting particle entrainment typically assume that clast weight is the only factor resisting motion in the force balance on individual grains. In this work, increases in the force required to dislodge surface particles due to overlapping by surrounding clasts is quantified. Field data were collected at two subaerially-exposed bars along the Colorado River in central Texas, USA, with median gravel diameters (D50) of 37 and 64 mm. Clast size, shape, weight, the force required for vertical removal, and the fraction of clast area covered by surrounding grains were measured. Small hooks were glued to individual clasts without disrupting their positions and quasi-static peak forces required to vertically dislodge each clast were measured using a force gauge. Clasts were also colored with dye before being dislodged, and image analysis was used to calculate the fraction of clast surface area covered by surrounding grains. The effect of overlap on the particle force balance is quantified by defining the ‘excess force ratio’ as the dislodgement force divided by the weight of the clast. Excess force ratio varies weakly but systematically with clast size: lifting larger clasts can require forces up to two times the clast's weight, while smaller clasts can require forces up to seven times their weight. The fraction of clast surface area covered by surrounding particles is also weakly correlated with excess force ratio. By assuming that critical shear stresses are proportional to the excess force ratio, the effect that overlap alone may have on particle entrainment is calculated. For a given size class, the most mobile grains should have critical shear stresses controlled only by their weight. However, clast overlap also causes broad distributions of critical stresses for partially-exposed surface grains. The data quantify the significant fraction of bed area that should be less mobile than grain size alone would predict. Copyright © 2011 John Wiley & Sons, Ltd.
From lignocellulosic biomass to renewable cycloalkanes for jet fuels

A novel pathway was investigated to produce jet fuel range cycloalkanes from intact biomass. The consecutive processes for converting lignocellulosic biomass into jet fuel range cycloalkanes principally involved the use of the well-promoted ZSM-5 in the process of catalytic microwave-induced pyrolysis and RANEY® nickel catalysts in the hydrogen saving process. Up to 24.68% carbon yield of the desired C8–C16 aromatics was achieved by catalytic microwave pyrolysis at 500 °C. We observed that solvents could assist in the hydrogenation reaction of naphthalene; and the optimum result for maximizing the carbon selectivity (99.9%) of decalin was obtained from the reaction conducted in the n-heptane medium. The recovery of organics could reach ∼94 wt% after the extraction process. These aromatics in the n-heptane medium were eventually hydrogenated into jet fuel range cycloalkanes. Various factors were analyzed to determine the optimal result under mild conditions. An increased catalyst loading, reaction temperature, and prolonged time could enhance the hydrogenation reactions to improve the selectivity of jet fuel range cycloalkanes. Three types of hydrogenation catalysts (NP Ni, RANEY® Ni 4200, home-made RANEY® Ni) were chosen to evaluate the catalytic performance. The results indicated that the home-made RANEY® nickel is the optimal catalyst to obtain the highest selectivity (84.59%) towards jet fuel range cycloalkanes. These cycloalkanes obtained can be directly used as additives to synthesize the desired jet fuels by blending with other hydrocarbons. Hence integration of catalytic processes and conversion of lignocellulosic biomass paved a new avenue for the development of green bio-jet fuels over inexpensive catalysts under mild conditions.
Multi‐scale modeling of the North Pacific Ocean: Assessment and analysis of simulated basin‐scale variability (1996–2003)

[1] A primitive equation ocean general circulation model is used to investigate climate impacts in the North Pacific Ocean in the 1996 to 2003 period. The objective is to assess the model ability to reproduce observed modes of variability and study their impact in the northeast Pacific. This work is done within the framework of the U.S. Global Ecosystem (GLOBEC) Northeast Pacific Program studying the links between climate variability and ecosystem dynamics. Three large-scale events are considered: The 1997/1998 El Nino, the 1999 “regime shift,” and the 2002 cold/fresh subsurface anomalous water mass that was observed in the Gulf of Alaska and off the coast of Oregon. The circulation model is shown to generate the correct seasonal to interannual large-scale variability and is able to represent the climatic signals of interest in the eastern Pacific. We show that the influence of the 1997/1998 El Nino reached the coastal Gulf of Alaska and induced an increase in the upper ocean heat content along the coast of North America. An analysis of the sea surface temperature for the model years shows agreement between model and data in the representation of the 1999 shift to a cold phase in the eastern and northern North Pacific. Finally, using the model results, we speculate that the origin of the 2002 cold/fresh anomaly in the northeast Pacific was due to enhanced mixing during the preceding winter in the center of the Alaska gyre. Owing to anomalous changes in the density structure of the upper ocean, this water was able to move geostrophically toward the coast and it persisted in the northeast Pacific below the mixed layer the following year.
Electromechanical properties of acceptor-doped lead-free piezoelectrics

In this paper, the processing and electrocmechanical of Mn-doped BNT-based ceramics prepared by mixed oxide route have been studied. Different amounts of Mn (0.01, 0.014, 0.015, 0.016, 0.017, 0.02, and 0.022) were doped to the 0.88[Bi0.5Na0.5TiO3]-0.08[Bi0.5K0.5TiO3]-0.04[Bi0.5Li0.5TiO3] ceramics. Samples were sintered at different temperatures (1075-1150 °C) to achieve the highest density and mechanical quality factor. Mn-doping resulted in a considerable enhancement of Qm in both planar and thickness vibration modes. In 1.5 mol.% Mn-doped ceramics sintered at 1100 °C, a planar Qm of about 970 and tanδ of 0.88% were obtained. Mn-doping also resulted in decreasing coupling coefficients, piezoelectric charge coefficient, and dielectric constant.
On Beyond Sudoku: Pencil Puzzles for Introductory Computer Science (Abstract Only)

Problem solving is a powerful teaching methodology for computer science -- giving students a real problem to solve instead of simply discussing abstract concepts can motivate them and give them a path to better understanding. However, it is challenging to create novel example problems that are meaningful and engaging yet can be easily understood by all students. In this workshop, we will introduce participants to the vibrant world of pencil puzzles and show how many different types of puzzles can be used for a variety of topics throughout the introductory CS curriculum. Pencil puzzles are those designed to be solved by hand with pencil and paper (such as Sudoku, but including dozens of new types!) that have clear rules and are made to be solved deductively. As such, they are explicitly designed to be easy to understand and intriguing and naturally inspire algorithmic thought. We will explore a variety of on-line resources, including our own curated repository, to see how assignments throughout the introductory CS curriculum can be easily kept fresh. Participants will also experience a sample problem-solving session and collaboratively develop a new assignment for a topic of the group's choice. This workshop is intended for all teachers (late secondary and post-secondary) of introductory programming courses. Laptops are recommended.
A computer running several psychological laboratories

Seven psychological laboratories, capable of testing 22 human and 4 animal Ss in seven different experiments using a variety of peripheral equipment, are in various stages of operation using an IBM 1800 process-control computer in the Psychology Department at Indiana University. Each experiment utilizes four appropriate software programs: SETUP, PROCEDURE, UI1LITY, and OUTPUT. The programming is usually simple enough to be done by nonprofessional programmers. This simplification was made possible by (1) a set of subroutines written to handle many of the process-control programming complexities, and (2) the IBM-provided Time-Sharing Executive (TSX) program.
A flow-cell method for measuring hepatic excretion of pigments continuously in rats

Abstract The electronic absorption of effluent bile from restrained rats with indwelling bile cannulas can be measured directly and continuously in the wavelength region 430–800 nm using commercially available micro flow-cells. The method is useful for studying and characterizing the hepatic excretion of endogenous and exogenous pigments. Biliary excretion curves are obtained directly without requiring separate analyses of individual bile samples. To demonstrate its application and scope, the technique has been used to follow the biliary excretion of sulfobromophthalein, rose bengal, biliverdin, and bilirubin.
Vacuolar uptake of host components, and a role for cholesterol and sphingomyelin in malarial infection

Erythrocytes, which are incapable of endocytosis or phagocytosis, can be infected by the malaria parasite Plasmodium falciparum. We find that a transmembrane protein (Duffy), glycosylphosphatidylinositol (GPI)-anchored and cytoplasmic proteins, associated with detergent-resistant membranes (DRMs) that are characteristic of microdomains in host cell membranes, are internalized by vacuolar parasites, while the major integral membrane and cytoskeletal proteins are not. The internalized host proteins and a plasmodial transmembrane resident parasitophorous vacuolar membrane (PVM) protein are detected in DRMs associated with vacuolar parasites. This is the first report of a host transmembrane protein being recruited into an apicomplexan vacuole and of the presence of vacuolar DRMs; it establishes that integral association does not preclude protein internalization into the P.FALCIPARUM: vacuole. Rather, as shown for Duffy, intracellular accumulation occurs at the same rate as that seen for a DRM-associated GPI-anchored protein. Furthermore, novel mechanisms regulated by the DRM lipids, sphingomyelin and cholesterol, mediate (i) the uptake of host DRM proteins and (ii) maintenance of the intracellular vacuole in the non-endocytic red cell, which may have implications for intracellular parasitism and pathogenesis.
Targeted inhibition of alphavbeta3 integrin with an RNA aptamer impairs endothelial cell growth and survival.

αvβ3 integrin is a crucial factor involved in a variety of physiological processes, such as cell growth and migration, tumor invasion and metastasis, angiogenesis, and wound healing. αvβ3 integrin exerts its effect by regulating endothelial cell (EC) migration, proliferation, and survival. Inhibiting the function of αvβ3 integrin, therefore, represents a potential anti-cancer, anti-thrombotic, and anti-inflammatory strategy. In this study, we tested an RNA aptamer, Apt-αvβ3 that binds recombinant αvβ3 integrin, for its ability to bind endogenous αvβ3 integrin on the surface of cells in culture and to subsequently affect cellular response. Our data illustrate that Apt-αvβ3 binds αvβ3 integrin expressed on the surface of live HUVECs. This interaction significantly decreases both basal and PDGF-induced cell proliferation as well as inhibition of cell adhesion. Apt-αvβ3 can also reduce PDGF-stimulated tube formation and increase HUVEC apoptosis through inhibition of FAK phosphorylation pathway. Our results demonstrate that by binding to its target, Apt-αvβ3 can efficiently inhibit human EC proliferation and survival, resulting in reduced angiogenesis. It predicts that Apt-αvβ3 could become useful in both tumor imaging and the treatment of tumor growth, atherosclerosis, thrombosis, and inflammation.
Three-dimensional structures of the prion protein and its doppel.

Transmissible spongiform encephalopathies (TSE) are neurodegenerative fatal diseases in mammalian species that appear to occur as rare, ‘‘sporadic’’ disorders, but also have been traced to mutations and to infectious transmission, including iatrogenic transfer [1,2]. Scrapie in sheep, bovine spongiform encephalopathy (BSE) in cattle, and the human TSEs—kuru, Creutzfeldt-Jakob disease (CJD), and variants thereof—have attracted interest beyond the scientific community. The basic neuropathologic signs in TSEs are a progressive vacuolation of brain tissue, and, usually, extensive astroglial hyperthrophy and proliferation, which is sometimes described as ‘‘spongiform change’’ [3]. The ‘‘protein-only hypothesis’’ [4–6] suggests that TSEs are distinct from infectious diseases caused by bacteria, viruses, or viroids in that the origin of the disease is related to conformational alterations of an ubiquitous protein—the prion protein (PrP)—and that nucleic acids are not essential for the propagation of the infectious agent. Accordingly, the normal cellular form of PrP (PrP C ) is transformed into the diseaserelated, and possibly in itself infectious, scrapie form (PrP Sc ) [2,6].
A model for the penetration of integuments by nonelectrolytes.

Abstract First-order kinetics have been observed in many experiments on the penetration of nonelectrolytes through animal integuments. Equations derived from Fick's Law are usually used to describe these results. However, the assumptions implicit in Fick's Law are in general not fulfilled by animal integuments. A mathematical treatment which assumes integuments to be composed of a number of immiscible phases also yields the observed first-order kinetics. The assumptions implicit in this treatment are fewer and better verified than those implicit in equations derived from Fick's Law.
The chemistry of scrapie infection: implications of the ‘ice 9’ metaphor

The transmissible spongiform encephalopathies pose an increasing problem for animal, and perhaps human, health. The infectious agent seems to lack a nucleic acid component, posing the question of how it can reproduce. A model of reproduction by nucleated polymerization suggests a number of novel approaches to the problem.
Accessing Scripts before Reading the Story.

Research has demonstrated that prior knowledge effects reading comprehension. The purpose of this study was to examine the effects on silent reading comprehension of learning disabled readers' participation in activities designed to access scripts before reading. Prior to silently reading basal stories, 24 school-identified learning disabled children were exposed to (a) a plans-and-goals activity and (b) a conceptual-overview statement activity. A two-way analysis of variance with repeated measures on all factors was used to analyze the data. The plans-and-goals activity was found to effect the children's reading comprehension significantly. Thus, the results support the purported importance of acquiring scriptual knowledge before reading.
Image quality improved 1X8 multimode interference coupler

A novel design of multimode interference coupler with deeply etched air trenches at the boundary of the multimode section is proposed for photonic integrated circuitry on low-index-contrast materials. The device length decreases from 820 microns to 750 microns for a 1X8 polymer multimode interference coupler. Due to the enhanced optical confinement, the optimized coupler with air trenches experimentally achieved 0.28/0.23dB reduced insertion loss, 2.16/2.34dB improved contrast ratio for TE and TM polarization, compared with conventional multimode interference coupler. The device entirely covers the wavelength range of both C-band and L-band, which is sufficient for broad band communication.
A study of search directions in primal-dual interior-point methods for semidefinite programming

We discuss several different search directions which can be used in primal-dual interior-point methods for semidefinite programming problems and investigate their theoretical properties, including scale invariance, primal-dual symmetry, and whether they always generate well-defined directions. Among the directions satisfying all but at most two of these desirable properties are the Alizadeh-Haeberly-Overton, Helmberg-Rendl-Vanderbei-Wolkowicz/Kojima-Shindoh-HaralMonteiro, Nesterov-Todd, Gu, and Toh directions, as well as directions we will call the MTW and Half directions. The first five of these appear to be the best in our limited computational testing also.
The simultaneous determination of the prostaglandins by chemospecific deuteration with separation and quantification by combined gas chromatography — chemical ionization mass spectrometry

Abstract A new gas chromatography/mass spectrometry (g.c./m.s.) procedure is described which simultaneously quantifies eight prostaglandins using one internal standard. The method could easily be extended to include more prostaglandins. The basis of the new method derives from two developments; 1) the discovery of quantitative chemospecific deuteration conditions for the C5–C6 double bonds of the prostaglandins (PG2), and 2) the development of special computer software to solve the analytical problem. Eight prostaglandins, present in the 1–100 ppm range, were determined with errors only occasionally over 10%. Substantially better performance may be expected with a more stable mass spectrometer. Samples with only 2 prostaglandins showed errors only occasionally over 1%.
Nixon's Administrative Presidency Revisited: Aberration or Watershed?

On 5 January 1973, one month after his reelection to a second term, Richard Nixon described for Congress a major restructuring of his cabinet and White House staff. Nixon began by emphasizing his determination to “revitalize and streamline the Federal Government in preparation for America's third century,” a reference to his effort of the preceding two years to replace seven domestic executive departments and several agencies with four “superdepartments”: a Department of Natural Resources, a Department of Community Development, a Department of Economic Affairs, and a Department of Human Resources. The failure of Congress to report out of committee any of the four bills Nixon submitted in March 1971 to create these superdepartments was now prompting the president to act unilaterally to “reorder … the timeworn and in many cases obsolete relationships among top staff and line officials” in an effort to realize “the broadening of policy perspectives on the part of top managers and advisers” and improvements in “managerial effectiveness” he had hoped to achieve through comprehensive reorganization of the executive branch.
Worker mobility and reservation wages for minority youth job seekers

Job offers requiring varying commuting times to work from inner-city areas and the reservation wages for a sample of young Chicano job seekers are examined. A logistic probability model of job acceptance using the minimum wage as an acceptance-rejection cutoff in relation to the reservation wage data is estimated by maximum likelihood techniques and suggests that the level of schooling is an important determinant of the probability of job acceptance. The results of this analysis suggest a restriction on the geographic range of job acceptances to the extent that minimum wage job offers located away from inner city, minority neighborhoods would most likely be rejected by the sample of minority youth job seekers.
Effects of nonlinearity on propagation in ionized media

The presence of an ionized media in the neighborhood of radio communication systems can degrade performance by: 1. Insertion of attenuation and distortion in each channel. 2. Interference between channels caused by generation of harmonics and sum and difference frequencies.
The Next Step for Ethics Education Is Enforcing the Code

If the university's corporate culture doesn't encourage compliance with our code of ethics, our classroom teaching on the topic is unlikely to be effective.
Modeling and control of two constrained manipulators

The coordinated control of two manipulators in the presence of environment constraints is studied in this paper. Such a control method is needed in applications in which the two manipulators grasp a common object whose motion is constrained by environments. The two manipulators are not only constrained with each other, but also constrained by the environment in their workspace. It is realized that the motion and constraint equations obtained directly from mechanics are not suitable for the control purpose. A set of equivalent equations are derived, which are in the standard form of the nonlinear system representation with clear state equations and output equations. A nonlinear feedback is found which exactly linearizes and decouples the dynamic nonlinear system of the two constrained manipulators. The coordinated controller design is then carried out based on the linearized system by using linear system theory.
Biological correlates of QT interval and QT dispersion in 2,265 patients with left ventricular ejection fraction [le ]40%

Abstract Increased QT interval and QT dispersion have been associated with increased mortality in a variety of cardiovascular disorders including heart failure. However, the biological correlates of these abnormalities are not clear. QTc and QTd were measured in an automated fashion from digitized electrocardiograms in 2,265 patients with an LV ejection fraction [le ]40% and were related to clinical, electrocardiographic, and echocardiographic variables. The QTc interval increased with increasing age ( P = .0003), heart rate ( P [lt ] .0001), LV dimensions ( P [lt ] .0001), left atrial diameter ( P [lt ] .0001), estimated right atrial pressure ( P [lt ] .0001), QRS duration ( P [lt ] .0001), bundle branch blocks ( P [lt ] .0001) and degree of mitral and tricuspid regurgitation ( P [lt ] .0001) and decreasing LV ejection fraction ( P [lt ] .0001) QT dispersion increased with increasing LV isovolumic relaxation time ( P = .004) and QTc ( P [lt ] .0001) and decreased with faster heart rate ( P [lt ] .0001) and higher right atrial pressure ( P = .0007). The biological relationships of QTc and QTd warrant further investigations.
Relationship between Drivers' Self-Reported Health and Technology Perceptions Across the Lifespan

This study examined relationships between individual user characteristics and perceptions about technology -- experience, adoption, ability to learn, and trust. Based on responses from a diverse sample of 610 individuals with driving experience, it was found that perceived health and well-being were strongly associated with experience and perceptions around technology, including attitudes toward established and new vehicle technologies. A comparison of results from a correlation analysis showed the effects of perceived health and well-being to be stronger and more significant compared to demographic characteristics and medical conditions. The findings suggest a need for a better understanding of user characteristics, rather than relying on observable traits.
Kinetics of the association of potential-sensitive dyes with model and energy-transducing membranes: implications for fast probe response times.

The second-order rate constants characterizing the association of potential-sensing dyes of the cyanine, merocyanine, and oxonol classes with glycerylmonooleate suspensions, azolectin vesicles, or submitochondrial particles have been measured and the implications for redistribution type mechanisms proposed to explain the potential-dependent optical signals of these probes considered. The second-order rate constants obtained for the cyanines and oxonols are compatible with microsecond probe response times only on the assumption that a high local dye concentration exists in the aqueous phase immediately adjacent to the membrane surface. Calculations based on a surface charge density induced by a bias potential suggest that the necessary local concentration cannot be attained by a diffusion polarization mechanism. A model based on the rapid recombination of ejected dye with the membrane bilayer seems capable of explaining microsecond probe response times in systems where the potential is rapidly changing polarity; calculations suggest that an ejected dye molecule would not diffuse out of an unstirred layer of 100 microns thickness on a millisecond time scale. Microsecond probe responses are also compatible with a first-order potential-dependent dye ejection from the membrane with no rapid recombination when the potential is not changing polarity. The apparent first-order rate constants describing the interaction of merocanine M-540 with a glycerylmonooleate suspension are independent of dye concentration; the reaction may be diffusion limited. The high local dye concentration need not be met in this case for a mechanism based on the transfer of dye onto the membrane from the aqueous phase to describe the microsecond signals of this dye, but other mechanisms have been proposed to explain such signals. The mechanism leading to potentialdependent signals from optical probes appear to differ substantially between suspensions of energy-transducing biological membranes and those involving excitable membranes such as the squid giant axon or model black lipid membranes.
Determination of semiconductor surface properties by means of photoelectric emission

Abstract Methods for determining the electronic energy levels at and near the surface of a semiconductor with the help of experimental energy distributions of photoelectrically emitted electrons are described. Information can be obtained about the type of optical transitions responsible for the yield near threshold of clean surfaces and the significance of the photoelectric threshold, about the work function, electron affinity and ionization energy of the surface, as well as the total amount of band bending near the surface. These quantities completely characterize the energy diagram of a semiconductor surface. The above information is obtained without any assumption being made about the photoelectric emission process. It is shown that photoemission out of surface states with a density as low as 1 state per 100 surface atoms can, in principle, be measured, provided the semiconductor does not have a large concentration (> 10 17 cm −3 ) of impurity states in the bulk.
Response of nanostructured Pt/GaN Schottky barriers to carbon monoxide

Abstract The interaction between CO and Pt can potentially be used to generate gas-sensing signals at Pt/GaN interfaces. Here, the CO response is compared to that generated by H2, and its dependence on Pt morphology is investigated. Similar to the H2 response, exposure to CO reduces the resistance of Pt/GaN structures. On dense, pinhole-free Pt films, the magnitude of the CO resistance change increases with decreasing Pt film thickness and with increasing Pt surface area, whereas discontinuous Pt films exhibit an increasing resistance change with film thickness. These results indicate that CO sensing is greatly affected by the Pt film morphology and the interaction between adsorbed CO and the charged Pt/GaN interface. A model is proposed in which surface charge induced by the adsorption of CO on Pt affects the interfacial polarization at the Pt/GaN interface. Simulations corroborate the proposed model. Transient resistance behavior is correlated with pre-adsorbed O species on the Pt surface and CO oxidation at atmospheric pressure, leading to a decrease of the Schottky barrier height and the resistance of the structure.
Biliary and renal excretion, hepatic metabolism, and hepatic subcellular distribution of metronidazole in the rat.

Abstract We studied the biliary and renal excretion, hepatic metabolism, and hepatic subcellular distribution of [14C]metronidazole in bile fistula rats. An average of 71.1 per cent of an intraduodenal or intravenous dose of [14C]metronidazole was excreted in 24 hr, 23.9 per cent in bile and 47.6 per cent in urine. Renal pedicle ligation caused a 150 per cent increase in biliary excretion of label, whereas phenobarbital pretreatment had no effect. The majority of label in bile and urine was associated with a polar derivative, tentatively identified by thin-layer chromatography and enzymatic hydrolysis as the monoglucuronide conjugate of metronidazole. After intraduodenal administration of purified conjugated [14C]metronidazole to rats with ligated renal pedicles, only a small amount of label (12.6 per cent of dose in 24 hr) appeared in bile. Growth inhibition studies showed the glucuronide conjugate to be devoid of antimicrobial activity against a metronidazole-sensitive organism, Tritrichomonas foetus. Uptake studies indicated that these organisms were incapable of concentrating conjugated metronidazole. Fractionation of rat liver homogenates by differential centrifugation after intravenous [14C]metronidazole showed that 90 per cent of label present in liver was in the non-particulate fraction. Our results in rats indicate that metronidazole undergoes an enterohepatic circulation and that the liver plays a major role in the metabolism and excretion of this compound.
Noncollinear folded mixing geometries for difference-frequency far infrared generation☆

Abstract Noncollinear folded geometries for far infrared generation by difference-frequency mixing of CO2 lasers are analyzed, and are shown theoretically to provide orders of magnitude increase in the far infrared output compared with the simple noncollinear geometry used previously. The basic principle of the folded geometry has been verified experimentally.
Local interfacial structures in horizontal bubbly flow with 90-degree bend

Present study investigates the geometric effects of flow obstruction on the distribution of local two-phase flow parameters and their transport characteristics in horizontal two-phase flow. The round glass tubes of 50.3mm in inner diameter are employed as test sections, along which a 90-degee elbow is located at L/D = 206.6 from the two-phase mixture inlet. In total, 15 different flow conditions are examined within the air-water bubbly flow regime. The detailed local two-phase flow parameters are acquired by the double-sensor conductivity probe at four different axial locations. The effect of elbow is found to be evident in both the distribution of local parameters and their development. The elbow clearly promotes bubble interactions resulting in significant changes in interfacial area concentration. It is also found that the elbow-effect propagates to be more significant further downstream (L/D = 250) than immediate downstream (L/D = 225) of the elbow. Furthermore, it is shown that the elbow induces significant oscillations in the flow in both vertical and horizontal directions of the tube cross-section. Characteristic geometric effects due to the existence of elbow are also shown clearly on the axial development of one-dimensional interfacial area concentration and void fraction.Copyright © 2006 by ASME
Structure and Magnetic Fields in the Precessing Jet System SS 433. I. Multifrequency Imaging from 1998

The Very Large Array has been used at five frequencies to study the structure and linear polarization of SS 433 on scales as small as ~0.1'' 500 AU . Each jet consists of a sharp, curving ridgeline at the leading edge, plus significant trailing off-jet emission, showing that they are enveloped by diffuse relativistic plasma. No kinematic model with constant jet speed fits our images on all scales, but they are consistent with variations in jet speed of around ±10% around the optical value. Our images show continuous jets with bright components occurring simultaneously in the two jets roughly every 35 days. When corrected for projection effects and Doppler boosting, the intensities of the two jets are intrinsically very similar. Fractional linear polarization up to 20% is present along the ridgelines, while the core is essentially unpolarized. The rotation measures are consistent with a foreground screen with RM + 110 rad m−2 plus a larger, asymmetrical contribution close to the core. The apparent magnetic fields in the jets are roughly aligned with the ridgelines in most but not all of each jet. The jet is more highly polarized between the components than in the components themselves, suggesting that the mechanism that creates them compresses a tangled part of the magnetic field into a partially ordered transverse layer. The off-jet emission is remarkably highly polarized, with m 50% in places, suggesting large-scale order of the magnetic field surrounding the jets. This polarized signal may confuse the determination of magnetic field orientations in the jets themselves. However, the images are consistent with a jet magnetic field that is everywhere parallel to the helices.
The Use of Telecommunication to Deliver Services to Rural and Urban Vocational Rehabilitation Clients.

Telecommunication offers a cost-saving alternative to face-to-face vocational rehabilitation (VR) service delivery, yet little is known about the current use. This article describes findings from a...
Principal component analysis of event-related potentials: Simulation studies demonstrate misallocation of variance across components ☆

Simulated event-related potential (ERP) components were used to investigate the ability of principal component analysis (PCA), Varimax rotation and univariate analysis of variance (ANOVA) to reconstruct component wave shapes, to allocate variance correctly across components, and to identify the correct locus of simulated experimental treatments. The simulated ERPs consisted of 800 randomly weighted combinations of three 64-point components, corresponding to a 2 X 2 X 10 repeated-measures design with 20 subjects. Covariance PCAs, Varimax rotations and univariate ANOVAs were performed on each of 400 such simulations, 100 with no effect of any experimental treatment and 100 each with main effects on each of the 3 components. Eight hundred additional simulations were performed to investigate the effects of systematic variations in the size of the experimental treatments and the number of subjects per experiment. The wave shapes of the simulated components were reconstructed reasonably well, although not completely, by the rotated principal component (PC) loadings. However, comparison of rotated PC scores with the random weights used to generate the simulated ERPs indicated that PCA incorrectly allocated variance across overlapping components, producing dramatic increases in type I error (the largest in excess of 80%) for ANOVAs on one component when the true treatment effect was on another. Although these results should not be overgeneralized, they clearly demonstrate that the PCA-Varimax-ANOVA strategy can incorrectly distribute variance across components, resulting in serious misinterpretation of treatment effects. Additional simulation studies are needed to determine the generality of the variance misallocation problem; pending the outcome of such studies, results obtained with the PCA-Varimax-ANOVA strategy should be interpreted cautiously.
The Cost-effectiveness of Hormone Therapy in Younger and Older Postmenopausal Women

Purpose: To evaluate the health and economic outcomes of hormone therapy in younger and older postmenopausal women. Methods: We developed a cost-effectiveness model to evaluate outcomes associated with hormone therapy in younger and older postmenopausal women, using data sources from published literature through March 2008. The target population was 50-year-old and 65-year-old women given hormone therapy or no therapy, and then followed over their lifetime. Primary outcomes measured were quality-adjusted life-years (QALYs) and incremental cost per QALY gained. Results: For the base-case analysis, hormone therapy for 15 years in the younger cohort resulted in a gain of 1.49 QALYs with an incremental cost of $2438 per QALY gained, compared with no therapy. The results for younger women were robust to all sensitivity analyses, and treatment remained highly cost-effective (<$10,000 per QALY gained) within the range of individual assumptions used. Treatment durations of 5 years and 30 years also were highly cost-effective. In the older cohort, treatment for 15 years resulted in a net gain of 0.11 QALYs with a cost of $27,953 per QALY gained. However, a loss of QALYs was seen in the first 9 years. The results for older women were sensitive to many of the assumptions used. Conclusions: Hormone therapy for 5 to 30 years in younger postmenopausal women increases quality-adjusted life-years and is cost-effective. Hormone therapy started in later years results in a loss of quality-adjusted life for several years before a net gain can be realized.
Symmetry restoration and the background field method in gauge theories

Abstract Spontaneously broken gauge theories in a constant external electromagnetic field are shown to exhibit a first-order phase transition to a restored symmetry phase when the external field exceeds a certain critical value. The effects of fields characterized by various values of the two Lorentz invariants F 1 = 1 2 (B 2 − E 2 ) and F2 = E · B are discussed. In a simple SU(2) model the critical field strength is found to be gR2(F1)crit = 0.057 mw4, mw being the vector boson mass. A number of theoretical developments in the background field formalism are presented. A new gauge-fixing term, the background field R gauge, is introduced. The configuration space heat kernel method for evaluating functional determinants, extended to allow the use of dimensional regularization, is employed, and it is shown how to perform background field calculations in a gauge specified by an arbitrary parameter α. Further applications of these methods are discussed.