cssi/SciSciGPT-SciSciNet huggingface dataset:
The cosmic gamma-ray bursts and their host galaxies in a cosmological context

Studies of the cosmic gamma-ray bursts (GRBs) and their host galaxies are now starting to provide interesting or even unique new insights in observational cosmology. Observed GRB host galaxies have a median magnitude R~25 mag, and show a range of luminosities, morphologies, and star formation rates, with a median redshift z~1. They represent a new way of identifying a population of star-forming galaxies at cosmological redshifts, which is mostly independent of the traditional selection methods. They seem to be broadly similar to the normal field galaxy populations at comparable redshifts and magnitudes, and indicate at most a mild luminosity evolution over the redshift range they probe. Studies of GRB optical afterglows seen in absorption provide a powerful new probe of the ISM in dense, central regions of their host galaxies, which is complementary to the traditional studies using QSO absorption line systems. Some GRB hosts are heavily obscured, and provide a new way to select a population of cosmological sub-mm sources. A census of detected optical tranistents may provide an important new way to constrain the total obscured fraction of star formation over the history of the universe. Finally, detection of GRB afterglows at high redshifts (z>6) may provide a unique way to probe the primordial star formation, massive IMF, early IGM, and chemical enrichment at the end of the cosmic reionization era.
Oceanic influences on recent continental warming

Evidence is presented that the recent worldwide land warming has occurred largely in response to a worldwide warming of the oceans rather than as a direct response to increasing greenhouse gases (GHGs) over land. Atmospheric model simulations of the last half-century with prescribed observed ocean temperature changes, but without prescribed GHG changes, account for most of the land warming. The oceanic influence has occurred through hydrodynamic-radiative teleconnections, primarily by moistening and warming the air over land and increasing the downward longwave radiation at the surface. The oceans may themselves have warmed from a combination of natural and anthropogenic influences.
Terahertz imaging system performance model for concealed-weapon identification

The U.S. Army Night Vision and Electronic Sensors Directorate (NVESD) and the U.S. Army Research Laboratory have developed a terahertz (THz) -band imaging system performance model for detection and identification of concealed weaponry. The MATLAB-based model accounts for the effects of all critical sensor and display components and for the effects of atmospheric attenuation, concealment material attenuation, and active illumination. The model is based on recent U.S. Army NVESD sensor performance modeling technology that couples system design parameters to observer-sensor field performance by using the acquire methodology for weapon identification performance predictions. This THz model has been developed in support of the Defense Advanced Research Project Agencies' Terahertz Imaging Focal-Plane Technology (TIFT) program and is currently being used to guide the design and development of a 0.650 THz active-passive imaging system. This paper will describe the THz model in detail, provide and discuss initial modeling results for a prototype THz imaging system, and outline plans to calibrate and validate the model through human perception testing.
Synthesis of a series of diaminobenzo[f]- and diaminobenzo[h]pyrimido[4,5-b]quinolines as 5-deaza tetracyclic nonclassical antifolates

A series of diaminobenzo[f]- and diaminobenzo[h]pyrimido[4,5-b]quinolines 1–11 were designed as 5-deaza tetracyclic nonclassical, lipophilic antifolates. The compounds were designed as conformationally semi-rigid and rigid analogs of 2,4-diamino-6-phenyl-12 and 2,4-diamino-7-phenylpyrido[2,3-d]pyrimidines 13 and 14. The target compounds were synthesized by cyclocondensation of chlorovinyl aldehydes obtained from appropriately substituted 1- or 2-tetralone, with 2,4,6-friaminopyrimidine. Compounds 1–11 were evaluated as inhibitors of P. carinii and T. gondii dihydrofolate reductases. These pathogens cause fatal opportunistic infections in AIDS patients. In addition, the selectivity of these agents was evaluated using rat liver dihydrofolate reductase as the mammalian source. In general the benzo[f]pyrimido[4,5-b]quinolines 1–5 were more potent than the corresponding benzo[h]pyrimido[4,5-b]quinoline analogues 6–11 against P. carinii and rat liver dihydrofolate reductase and were equipotent against T. gondii dihydrofolate reductase. Compounds 6–11 were moderately selective towards T. gondii dihydrofolate reductase with IC50S in the 10−7 M range. In contrast analogues 1–5 lacked selectivity against P. carinii or T. gondii dihydrofolate reductase and were, in general, potent inhibitors of rat liver dihydrofolate reductase with IC50S in the 10−8 M range. Analogues 1 and 4 were evaluated against a series of tumor cell lines in vitro and were found to have moderate antitumor activity (IC50 10−6 M). The structure activity/selectivity relationships suggest that benzo[f]pyrimido analogues 1–5 with the phenyl ring substitution in the “upper” portion of the tetracyclic ring are better accommodated within the rat liver (mammalian) dihydrofolate reductase and P. carinii dihydrofolate reductase active sites compared to the benzo[h]pyrimido analogues 6–11 which have the phenyl ring substitution in the “lower” portion of the tetracyclic ring. In contrast T. gondii dihydrofolate reductase does not discriminate between the isomers and binds to both series of compounds with similar affinities.
Changes in Human Development in Developing Countries: An Empirical Assessment

Based on data from the World Bank and the United Nations Development Programme, a sample of 29 developing economies was used. The finding is that cross-country changes in human development may be explained by per capita GDP growth, the length of land boundaries, the percentage of children under age 5 whose weight is more than two standard deviations below the median for the international reference population ages 0-59 months, the under-5 mortality rate, the ratio of girls to boys in primary and secondary education, the prevalence of HIV, the national average distance to the capital city, and the income share held by the lowest 10% of population. As observed, the coefficient estimates of three independent variables do not have the anticipated sign due to the severe degree of multicollinearity among statistically significant explanatory variables. Data for all variables are from the 2010 World Development Indicators and the 2009 Human Development Report. The least-squares estimation technique in a multivariate linear regression was applied. As noted, the severe degree of multicollinearity among explanatory variables may have caused their coefficient estimates to have the wrong sign.
The Rise of Self-Employment in Rural China: Development or Distress?

Summary This paper evaluates the role of self-employment in China’s rural economy, while paying attention to whether the rise of self-employment promotes entrepreneurship and is a sign of development, or whether it is a stopover for disadvantaged workers and a sign of distress. Using data on 20-year labor market histories of a nationally representative sample of individuals, we provide descriptive evidence that self-employment in rural China, unlike in some other places, is a sign of development. Econometric evidence from a random-effects probit model and a continuous-time Markov model shows also that self-employment in rural China shares many features of a productive small-business sector.
Effective corporate networking, organization, and standardization

As investment in automatic data processing systems has increased, methods to improve the productivity of these systems have constantly been sought. One of the most promising methods is networking---the integration of a number of independent data processing installations connected by data communications to provide improved data processing support for the linked installations.
Direct Catalytic Anti-Markovnikov Hydroetherification of Alkenols

A direct intramolecular anti-Markovnikov hydroetherification reaction of alkenols is described. By employing catalytic quantities of commercially available 9-mesityl-10-methylacridinium perchlorate and 2-phenylmalononitrile as a redox-cycling source of a H-atom, we report the anti-Markovnikov hydroetherification of alkenes with complete regioselectivity. In addition, we present results demonstrating that this novel catalytic system can be applied to the anti-Markovnikov hydrolactonization of alkenoic acids.
Staggered Fermion Thermodynamics using Anisotropic Lattices

Abstract Numerical simulations of full QCD on anisotropic lattices provide a convenient way to study QCD thermodynamics with fixed physics scales and reduced lattice spacing errors. We report results from calculations with 2-flavors of dynamical fermions where all bare parameters and hence the physics scales are kept constant while the temperature is changed in small steps by varying only the number of the time slices. The results from a series of zero-temperature scale setting simulations are used to determine the Karsch coefficients and the equation of state at finite temperatures.
Convergence of a Substructuring Method with Lagrange Multipliers

We analyze the convergence of a substructing iterative method with Lagrange multipliers, propose recently by Farhat and Roux. The method decomposes finite element discretization of an elliptic boundary value problem into Neumann problems on the subdomains plus a coarse problem for the subdomain nullspace components. For linear conforming elements and preconditioning by the Dirichlet problems on the subdomains, we prove the asymptotic bound on the condition number C(1+log(H/h))^\alpha, \alpha=2 or 3, where h is the characteristic element size, H subdomain size, and C is independent of the number of subdomains.
Application of blue noise mask in color halftoning

Color halftoning using a conventional screen requires rotating the screen by different angles for different color planes to avoid Moire patterns. An obvious advantage of halftoning using a blue noise mask (BNM) is that there are no screen angles or Moire patterns. However, a simple strategy of employing the same BNM on all color planes is unacceptable in cases where a small registration error can cause objectionable color shifts. In a previous paper, we proposed shifting or inverting the BNM for different color planes. The shifting technique can, at certain shift values, introduce low frequency contents into the halftone image, whereas the inverting technique can be used only on two color planes. In this paper, we propose a technique that uses four distinct BNMs that are correlated in a way such that the low frequency noise resulting from the interaction between the BNMs is significantly reduced.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
MULTI-SCALE MORPHOLOGICAL ANALYSIS OF SDSS DR5 SURVEY USING THE METRIC SPACE TECHNIQUE

Following the novel development and adaptation of the Metric Space Technique (MST), a multi-scale morphological analysis of the Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) was performed. The technique was adapted to perform a space-scale morphological analysis by filtering the galaxy point distributions with a smoothing Gaussian function, thus giving quantitative structural information on all size scales between 5 and 250 Mpc. The analysis was performed on a dozen slices of a volume of space containing many newly measured galaxies from the SDSS DR5 survey. Using the MST, observational data were compared to galaxy samples taken from N-body simulations with current best estimates of cosmological parameters and from random catalogs. By using the maximal ranking method among MST output functions, we also develop a way to quantify the overall similarity of the observed samples with the simulated samples.
The Resurgence of Regional Economies, Ten Years Later The Region as a Nexus of Untraded Interdependencies

Since the early 1980s, social scientists have increas ingly focused upon the significance of the region to the organization of economic life. This article considers three main lines of analysis which have emerged. These concentrate respectively on insti tutions, industrial organization and transactions, and technological change and learning. Each has made strong claims about the role of the region. I argue here, however, that none has yet developed a wholly convincing explanation for the resurgence of regional economies. To do this it is necessary to understand the region as a locus of untraded interdependencies. This has implications for how we think about regional and industrial policies. I illustrate these points with some remarks on regional policies in contemporary Europe.
Bone turnover is not influenced by serum 25-hydroxyvitamin D in pubertal healthy black and white children.

Abstract Low serum 25-hydroxyvitamin D [25 (OH) D] is common in healthy children particularly in blacks. However, serum 25 (OH) D concentrations for optimal bone turnover in children is unknown and few data exist that describe effects of increasing serum 25 (OH) D on bone turnover markers during puberty. The purpose of this study was to determine the relationships between serum 25 (OH) D and changes in serum 25 (OH) D and bone turnover in white and black pubertal adolescents. Bone turnover markers were measured in 318 healthy boys and girls from Georgia (34°N) and Indiana (40°N) who participated in a study of oral vitamin D 3 supplementation (0 to 4000 IU/d). Serum 25 (OH) D, osteocalcin, bone alkaline phosphatase, and urine N-telopeptide cross-links were measured at baseline and 12 weeks. Relationships among baseline 25 (OH) D and bone biomarkers, and between changes over 12 weeks were determined and tested for effects of race, sex, latitude, and baseline 25 (OH) D. Median 25 (OH) D was 27.6 ng/mL (n = 318, range 10.1–46.0 ng/mL) at baseline and 34.5 ng/mL (n = 302, range 9.7–95.1 ng/mL) at 12 weeks. Neither baseline nor change in 25 (OH) D over 12 weeks was associated with bone turnover. The lack of association was not affected by race, sex, latitude, or baseline serum 25 (OH) D. Serum 25 (OH) D in the range of 10–46 ng/mL appears to be sufficient for normal bone turnover in healthy black and white pubertal adolescents.
Effect of preoxidation and grain size on ductility of a boron-doped Ni3Al at elevated temperatures

Abstract The ductility of a preoxidized Ni3Al (Ni-23Al-0.5Hf-0.2B. at.%) alloy with various grain sizes (17–193 μm) was evaluated by means of tensile tests at 600 and 760°C in vacuum. The preoxidation does not affect the ductility of the finest-grained material at either temperature, whereas it causes severe embrittiement in the largest-grained material, especially at 760°C. Auger studies revealed very little oxygen penetration along grain boundaries in the finest-grained material but substantial oxygen penetration in the largest-grained one. A continuous, thin Al-rich oxide layer which forms on the fine-grained samples protects the underlying alloy from oxygen penetration, preventing any loss of ductility, whereas the nickel-rich oxide which forms on the large-grained samples allows oxygen to penetrate along grain boundaries, causing severe embrittiement. The grain boundaries act as short-circuit paths for rapid diffusion of aluminum atoms from the bulk to the surfaces, and this is responsible for the change in oxidation product from Ni-rich to Al-rich oxide with decreasing grain size.
Galois Switching Functions and Their Applications

The Boolean difference expansion of Boolean algebra is generalized to finite (Galois) fields. A systematic method is provided for calculating the coefficients of this type of multivariable polynomial expansion. It is applied then to the synthesis functions. Applications include multivalued logics as well as binary-valued logics.
The homotopy dimension of codiscrete subsets of the 2-sphere ²

We characterize those planar Peano continua that are homotopy equivalent to 1-dimensional sets. While many planar Peano continua are not homotopically 1-dimensional, we prove that each has fundamental group that embeds in the fundamental group of a 1-dimensional planar Peano continuum. We leave open the following question: Is a planar Peano continuum homotopically 1- dimensional if its fundamental group is isomorphic with the fundamental group of a 1-dimensional planar Peano continuum?
A review of reactions of some sterols in strongly acidic media

Abstract Sterols are protonated in strongly acidic media and form carbocations which are in equilibrium with olefins. Olefins react with carbocations and the hydride transfer involved yields an allylic carbocation and a cycloalkane. Allylic carbocations formed absorb in the 300- to 320-nm range. A diene formed by dissociation of the allylic carbocation reacts similarly with a carbocation and yields a dienylic carbocation absorbing at 360–380 nm. A dication formed rapidly from cholesterol, more slowly from hyodeoxycholic acid, and even more slowly from chenodeoxycholic acid absorbs at 350 nm. Studied compounds included (a) estrogens and related steroids with an aromatic ring A and a hydroxy group on ring D; (b) Δ4-3-ketosteroids with a hydroxy group on ring D; (c) cholesterol and polyenic cholestanes; (d) bile acids. Competing reactions producing polyenylic carbocations occur with considerably varying rates and dependence on acidity. Variation of rates with sulfuric acid concentration indicates that at [H2SO4] w w ) sulfuric acid is not a reactant, but rather a medium controlling acidity. Optimum analytical conditions differ for individual sterols. For determination of each sterol is it necessary to study the dependence of the rate of generation of the chromogen on acidity to find the optimum acidity and reaction time.
Low temperature properties of holographic condensates

In the current work we study various models of holographic superconductors at low temperature. Generically the zero temperature limit of those models are solitonic solution with a zero sized horizon. Here we generalized simple version of those zero tem- perature solutions to small but non-zero temperature T. We confine ourselves to cases where near horizon geometry is AdS 4 . At a non-zero temperature a small horizon would form deep inside this AdS 4 which does not disturb the UV physics. The resulting geometry may be matched with the zero temperature solution at an intermediate length scale. We understand this matching from separation of scales by setting up a perturbative expansion in gauge potential. We have a better analytic control in abelian case and quantities may be expressed in terms of hypergeometric function. From this we calculate low tempera- ture behavior of various quatities like entropy, charge density and specific heat etc. We also calculate various energy gaps associated with p-wave holographic superconductor to understand the underlying pairing mechanism. The result deviates significantly from the corresponding weak coupling BCS counterpart.
Distorting mixed tsirelson spaces

Any regular mixed Tsirelson spaceT(θ n ,S n )N for whichθ n /θ n → 0, whereθ=lim n θ 1 , is shown to be arbitrarily distortable. Certain asymptoticl 1 constants for those and other mixed Tsirelson spaces are calculated. Also, a combinatorial result on the Schreier families (S α ) α<ω 1 is proved and an application is given to show that for every Banach spaceX with a basis (e i ), the two Δ-spectrums Δ(X) and Δ(X, (e i )) coincide.
Wavepacket theory of collisional dissociation in molecules

Abstract An explicit integration scheme is used to solve the time dependent Schrodinger equation for wavepackets which model collisions in the collinear H + H 2 system. A realistic LEPS-type potential energy surface is used. Collision energies considered are above the dissociation threshold and probabilities for collision induced dissociation are reported. Also quantum mechanical state-to-state transition probabilities are generated. These results are compared to extensive classical trajectory calculations performed on this same system. We study the time evolution of the wavepacket densities to understand the dynamics of the collinear collisional dissociation process.
Tin-free radical reactions under minimal solvent conditions for the synthesis of substituted chromones and coumarins

An alkyltin-free radical methodology carried out under minimal solvent conditions is presented. This free radical addition process allows for the preparation of a variety of substrates, including substituted chromones and coumarins. This method is high yielding, conducted at ambient temperature and, in nearly all instances, classical purification techniques such as chromatography are not needed.
Impact of Homopolymer Pore Expander on the Morphology of Mesoporous Carbon Films using Organic-Organic Self-Assembly

Soft templated mesoporous carbon films (ca. 60 nm thick) are fabricated by the cooperative assembly of poly(styrene-block-ethylene oxide) (PS-b-PEO) with phenolic resin, where the pore sizes are tuned by the addition of polystyrene oligomers (hPS) to this self-assembling system. Significant differences in the morphology and pore expansion are found for the thin films in comparison to previously reported bulk powders using a similar system. The film porosity is nearly independent of swelling agent content for addition of up to 10 wt % hPS; this limited effect is attributed to surface segregation of the hPS on the basis of wetting considerations, which decreases the effective concentration of hPS in the hydrophobic domains. The templated synthesis yields a relatively narrow pore size distribution for 10 wt % hPS. Elliptical pores are formed due to the uniaxial contraction that occurs during carbonization...
Bureaucratic imperatives and policy outcomes: The origins of World Bank structural adjustment lending

ABSTRACT Although the impact of World Bank and IMF structural adjustment loans on developing country borrowers has been the subject of considerable analysis, our understanding of the origins of these operations remains poor. This article rectifies this deficiency by providing an account of the genesis of the Bank's program of structural adjustment. Drawing on documents from the Bank's archives as well as interviews with former Bank officials, the paper argues that the creation of structural adjustment lending in 1980 resulted from frustration among the Bank's senior management at the slow disbursement of the organization's regular project loans. Rather than a reaction to demands from powerful states, as many observers have assumed, structural adjustment was an internally driven response to flaws in the Bank's operations. In emphasizing the Bank's autonomy, this article supplements approaches that emphasize the importance of budget maximization and mission creep as determinants of international organizatio...
An in Situ Time-Dependent Study of CO Oxidation on Pt(111) in Aqueous Solution by Voltammetry and Sum Frequency Generation

In situ time-dependent measurements using voltammetry and sum frequency generation (SFG) were carried out to study CO oxidation on a Pt(111) electrode. The scan-rate dependence of CO oxidation was measured by changing the scan rate from 50 to 0.5 mV/s. While the basic shape of the CO stripping curves was unaffected by sweep rate, the oxidation potential of CO was lowered by 0.1 V, from 0.84 to 0.74 V. The measurements of SFG spectra and CO stripping were carried out simultaneously to clarify the discrepancy between SFG and CO stripping measurements reported in earlier SFG studies. Our results showed that the SFG peak attributed to the CO stretch vanished immediately after the CO stripping current reached its maximum value. In the preignition potential region, the frequency shift of the CO stretch observed by SFG agrees with that observed by IR spectroscopy. Additionally, in the ignition potential region, a significant blue shift of CO stretching frequency was observed. For the first time, a 360% enhanceme...
Anaesthesia for caesarean delivery in a patient with May-Hegglin anomaly.

The anaesthetic management for Caesarean delivery is described in a patient with May- Hegglin anomaly. The condition, which is inherited as an autosomal dominant characteristic, has features of thrombocytopenia and a bleeding diathesis. Labour was induced and she received type specific platelet transfusion. Spinal anaesthesia, using five per cent lidocaine, 75 mg, with epinephrine and 0.5 mg morphine sulphate produced satisfactory operating conditions, excellent postoperative analgesia, and uncomplicated initial recovery.
H+/ATP stoichiometry of proton pumps from Neurospora crassa and Escherichia coli.

Abstract A kinetic method has been used to measure the apparent stoichiometry of H+ ions translocated per ATP split by membrane-bound [H+]-ATPases. In this method, membrane vesicles are suspended in well-buffered medium, ATP is added, and a fluorescent probe of ΔpH (acridine orange) is used to detect the formation of a steady-state pH gradient. At the steady state, it is assumed that proton pumping in one direction is exactly balanced by the leak of protons in the opposite direction. The pump is then rapidly turned off by the addition of an appropriate inhibitor, and the initial rate of relaxation of ΔpH is used to infer the pump rate. This rate is divided by the rate of ATP hydrolysis, measured under the same condition, to give the apparent H + ATP stoichiometry. The method has been applied to two different [H+]-ATPases, the plasma-membrane ATPase of Neurospora (a Mr = 100,000 integral membrane protein) and the ATPase of Escherichia coli (which belongs to the F0F1 group). The Neurospora ATPase displayed an apparent stoichiometry close to 1 H + ATP (0.82–1.23), in agreement with previous estimates from electrophysiological measurements on whole cells. In contrast, the E. coli ATPase yielded an apparent stoichiometry close to 2H + ATP (1.90), consistent with several published values obtained by both kinetic and thermodynamic methods for bacterial, mitochondrial, and chloroplast ATPases.
MHD turbulence: relaxation processes and variational principles

Abstract Turbulent relaxation processes seem to play a more prominent role in magnetohydrodynamics (MHD) than in hydrodynamics and exhibit a wider variety of behavior. In decaying turbulence, “relaxed” states can result from highly unequal decay rates of extensive, cascadable ideal invariants such as energy, magnetic helicity, cross helicity, etc. In externally-driven MHD systems, the relaxed states may result from other processes, less well understood. We are exploring a formulation based on a principle of the minimum rate of energy dissipation. This is a nineteenth century principle from which seems to descend the more modern (and less well accepted) principle of “the minimum rate of entropy production”. Consequences of the conjectured principle are described for two cases: (1) for the reversed-field pinch (RFP), an externally-applied electric field supplies magnetic helicity at a constant rate; (2) for the case of a constant rate of dissipation of cross-helicity, a relaxed state with aligned vorticity and current densities is predicted. The former problem models the steady-state operation of a familiar fusion confinement device. The latter models certain features of solar wind turbulance, regarded as a driven, steady-state system.
Intracellular temperature mapping with fluorescence-assisted photoacoustic thermometry

Measuring intracellular temperature is critical to understanding many cellular functions but still remains challenging. Here we present a technique – fluorescence-assisted photoacoustic thermometry (FAPT) – for intracellular temperature mapping applications. To demonstrate FAPT, we monitored the intracellular temperature distribution of HeLa cells with sub-degree (0.7 °C) temperature resolution and sub-micron (0.23 μm) spatial resolution at a sampling rate of 1 kHz. Compared to traditional fluorescence-based methods, FAPT features the unique capability of transforming a regular fluorescence probe into a concentration- and excitation-independent temperature sensor, bringing a large collection of commercially available generic fluorescent probes into the realm of intracellular temperature sensing.
Proof of Blum's conjecture on hexagonal dungeons

Abstract Matt Blum conjectured that the number of tilings of the hexagonal dungeon of sides a, 2a, b, a, 2a, b (where b ⩾ 2 a ) is 13 2 a 2 14 ⌊ a 2 2 ⌋ (Propp, 1999 [4] ). In this paper we present a proof for this conjecture using Kuo's Graphical Condensation Theorem (Kuo, 2004 [2] ).
Instantaneous frequency and kernel requirements for discrete time-frequency distributions

Abstract In this paper, we introduce a new definition for the in- stantaneous frequency of a discrete-time analytic signal.Unlike the existing definition which uses only two data samples around a particular time, this method utilizes all the data samples for estimating the instantaneous fre- quency. We prove that this quantity is identical to the average frequency evaluated at the particular time in thediscrete-time TFD. This property is consistent with theanalogous continuous-time property. We also derive re-quirements on the discrete-time kernel needed to satisfythis property. Using computer-generated signals and realdata, performance comparisons are made between the pro-posed approach and the existing one. 1 Introduction The mixed time-frequency distribution (TFD) has re- ceived considerable attention recently as a powerful toolfor analyzing a variety of deterministic and stochastic sig- nals [2,7,14]. A TFD is used in an attempt to localizefrequency content in time. The spectrogram has been
LORENTZ ANOMALY IN ARBITRARY DIMENSIONS

It is shown that the Lorentz invariance is broken in gauge theories of chiral Weyl fermions in flat space-time via one-loop quantum corrections. Abelian gauge fields contribute to this anomaly in even dimensions larger than or equal to four and non-Abelian gauge fields do in even dimensions larger than or equal to six. The anomaly is proportional toD/2–1 power to the charge, whereD is a number of space-time dimensions.
Retirement and Death in Office of U.S. Supreme Court Justices

We construct demographic models of retirement and death in office of U.S. Supreme Court justices, a group that has gained demographic notice, evaded demographic analysis, and is said to diverge from expected retirement patterns. Models build on prior multistate labor force status studies, and data permit an unusually clear distinction between voluntary and “induced” retirement. Using data on every justice from 1789 through 2006, with robust, cluster-corrected, discrete-time, censored, event-history methods, we (1) estimate retirement effects of pension eligibility, age, health, and tenure on the timing of justices’ retirements and deaths in office, (2) resolve decades of debate over the politicized departure hypothesis that justices tend to alter the timing of their retirements for the political benefit or detriment of the incumbent president, (3) reconsider the nature of rationality in retirement decisions, and (4) consider the relevance of organizational conditions as well as personal circumstances to retirement decisions. Methodological issues are addressed.
Motion of a cadaver model of cervical injury during endotracheal intubation with a Bullard laryngoscope or a Macintosh blade with and without in-line stabilization.

Background:Endotracheal intubation in patients with potential cervical injury is a common dilemma in trauma. Although direct laryngoscopy (DL) with manual in-line stabilization (MILS) is a standard technique there is little data on the effect of MILS on cervical motion. Likewise there is little data
Interannual variability of global dust storms on Mars

Global dust storms on Mars occur in some years but not in others. If the four Mars years of Viking data are representative, some distinguishing characteristics can be inferred. In years with global dust storms, dust is raised in the southern hemisphere and spread over much of the planet by an intensified Hadley circulation. In years without global dust storms, dust is raised in the northern hemisphere by relatively active mid-latitude storm systems but does not spread globally. In both cases the dusty season is winter in the north. Assuming that the cross-equatorial Hadley circulation plays a key role in the onset of global dust storms, it is shown from numerical simulations that a northen hemisphere dust haze weakens its intensity and, hence, its contribution to the surface stress in the southern hemisphere. This, in turn, reduces the possibility of global dust storm development. The interannual variability is therefore the result either of a competition between circulations in opposite hemispheres, in which case the variability has a random component, or it is the result of the cycling of dust between hemispheres, in which case the variability is related to the characteristics of global dust storms themselves.
A Robotic System for Real-Time Tumor Manipulation During Image Guided Breast Biopsy

Breast biopsy guided by imaging techniques is widely used to evaluate suspicious masses within the breast. Current procedure allows the physician to determine location and extent of a tumor in the patient breast before inserting the needle. There are several problems with this procedure: Complex interaction dynamics between needle and breast tissue will likely displace the tumor from its original position necessitating multiple insertions, causing surgeons’ fatigue, patient’s discomfort, and compromising integrity of the tissue specimen. We present a new concept for real-time manipulation of a tumor using a robotic system that monitors the image of the tumor to generate appropriate external force to position the tumor at a desired location. The objective is to demonstrate that it is possible to manipulate a tumor in real-time by applying controlled external force in an automated way such that the tumor does not deviate from the path of the needle. We have demonstrated efficacy of this approach on breast phantoms. The robotic system consists of an ultrasound probe for image acquisition, a guiding mechanism for automatic probe orientation, image processing algorithm for extracting tumor position and PID (proportional-integral-derivative) controlled actuators for tumor manipulation. We have successfully tested this system for accessing mobile lesions during multiple needle insertion trials. This approach has the potential to reduce the number of attempts a surgeon makes to capture the desired tissue specimen, minimize tissue damage, improve speed of biopsy, and reduce patient discomfort.
A preliminary look at how geometry influences the magneto-mechanical behavior of magnetic shape memory alloys

Magnetic shape memory alloys (MSMAs) are new materials that emerged in the late 1990s. The magnetic shape memory effect is a result of the rearrangement of martensitic variants under the influence of magnetic fields. Due to their newness there is limited understanding of the mechanical behavior of MSMAs. However, it is know that MSMAs are able to produce relatively large strains as compared to piezoelectric materials or conventional shape memory alloys (SMAs). In addition, MSMAs have a lower time constant than conventional SMAs, since their actuation frequency is not limited by heat transfer. These features make MSMAs attractive for a number of applications, but they must be thoroughly understood before they can be used. This work includes an experimental investigation on MSMAs where the material is loaded and unloaded in uniaxial compression in the presence of a perpendicular constant magnetic field. The modeling of the magneto-mechanical behavior of MSMAs under such loading is also presented. The experiments are performed on prismatic specimens with square and rectangular base. The experimental data is simulated using the Kiefer and Lagoudas model and a polynomial hardening rule calibrated on data from Couch et al.
Draco 119: A Remarkable Heavy-Element-deficient Giant*

We report the abundance analysis of new high signal-to-noise ratio (S/N) spectra of the most metal-poor ([Fe/H] = -2.95) star currently known to be a member of a dwarf galaxy, the Draco dSph red giant D119. No absorption lines for elements heavier than Ni are detected in two Keck HIRES spectra covering the 3850-6655 A wavelength range, a phenomenon not previously noted in any other metal-poor star. We present upper limits for several heavy-element abundances. The most stringent limits, based on the nondetection of Sr II and Ba II lines, indicate that the total s- and r-process enrichment of D119 is at least 100 times smaller than Galactic stars of similar metallicity. The light-element abundances are consistent with the star having formed out of material enriched primarily by massive Type II supernovae (M > 20-25 M☉). If this is the case, we are forced to conclude that massive, metal-poor Type II supernovae did not contribute to the r-process in the proto-Draco environment. We compare the abundance pattern observed in D119 to current predictions of prompt enrichment and pair-instability supernovae and find that the model predictions fail by an order of magnitude or more for many elements.
Fully intermolecular nickel-catalyzed three-component couplings via internal redox.

Two distinct nickel-catalyzed fully intermolecular three-component couplings are described. The catalytic addition of enals, alkynes, and alcohols provides γ,δ-unsaturated esters, whereas the catalytic addition of enones, alkynes, and aldehydes provides stereodefined, unsymmetrical 2-allyl-1,3-diketones. An internal redox process allows the reactions to proceed in the absence of reducing agents. On the basis of deuterium-labeling studies, a likely mechanistic pathway is proposed.
Are Whites Still Fleeing? Racial Patterns and Enrollment Shifts in Urban Public Schools, 1987–1996

The effect of interracial contact in public schools on the enrollment of whites has been an important concern in assessments of desegregation since the 1970s. It has been feared that “white flight”—meaning exit from or avoidance of racially mixed public schools—could undermine the racial contact that desegregation policy seeks to enhance. This study examines this question using recent data. It also expands coverage from large urban districts to entire metropolitan areas, paying attention to the spatial context within which enrollment decisions are made. To do so, it examines data for 1987 and 1996 on racial composition and enrollment in all schools and school districts in 238 metropolitan areas. The study finds that white losses appear to be spurred both by interracial contact in districts where their children attend school and by the opportunities available in metropolitan areas for reducing that contact. These findings apply with remarkable consistency to large and small districts in both large and small metropolitan areas. Implications for metropolitan segregation are examined. © 2001 by the Association for Public Policy Analysis and Management.
Black holes in massive gravity: quasi-normal modes of scalar perturbations

We have studied quasinormal modes of scalar perturbations of a black hole in massive gravity. The parameters of the theory, such as the mass of the black hole, the scalar charge of the black hole and the spherical harmonic index is varied to see how the corresponding quasinormal frequencies change. We have also studied the massive scalar field perturbations. Most of the work is done using WKB approach while sections are devoted to compute quasinormal modes via the unstable null geodesics approach and the Poschl–Teller approximation. Comparisons are done with the Schwarzschild black hole.
Distributive Products and Their Homology

We develop a theory of sets with distributive products (called shelves and multi-shelves) and of their homology. We relate the shelf homology to the rack and quandle homology.
Optimally Computing the Shortest Weakly Visible Subedge of a Simple Polygon

Given ann-vertex simple polygonP, the problem of computing the shortest weakly visible subedge ofPis that of finding a shortest line segmentson the boundary ofPsuch thatPis weakly visible froms(ifsexists). In this paper, we present new geometric observations that are useful for solving this problem. Based on these geometric observations, we obtain optimal sequential and parallel algorithms for solving this problem. Our sequential algorithm runs inO(n) time, and our parallel algorithm runs inO(logn) time usingO(n/logn) processors in the CREW PRAM computational model. Using the previously best known sequential algorithms to solve this problem would takeO(n2) time. We also give geometric observations that lead to extremely simple and optimal algorithms for solving, both sequentially and in parallel, the case of this problem where the polygons are rectilinear.
Optimal search strategies in dynamic hypothesis testing

The author formulates and solves a class of dynamic search problems for obtaining the closed-loop sequence of measurements which, under a symmetry condition on the probability distribution of the measurements, optimally selects among many candidate hypotheses. Under this condition, the optimal strategy is characterized by a simple index rule which depends only on the ordering of the conditional probabilities of the hypotheses given the past measurements. The author proves that this index rule is optimal independent of the number of measurements to be taken. The author illustrates with numerical examples that, when the symmetry conditions are relaxed, the index policies are suboptimal, but achieve performance which is close to optimal. The results can be applied to solve complex problems in fault diagnosis and search with unreliable tests. >
A Combinatorial user optimal dynamic traffic assignment algorithm

This paper introduces a polynomial combinatorial optimization algorithm for the dynamic user optimal problem. The approach can efficiently solve single destination networks and can be potentially extended to heuristically solve multidestinational networks. In the model, traffic is propagated according to sound traffic flow theoretical models rather than link exit functions; thereby allowing link queue evolution to be modeled more precisely. The algorithm is designed, proven, implemented and computationally tested.
Studies of the over-rotating BMPV solution

We study unphysical features of the BMPV black hole and how each can be resolved using the enhancon mechanism. We begin by reviewing how the enhancon mechanism resolves a class of repulson singularities which arise in the BMPV geometry when D-branes are wrapped on K3. In the process, we show that the interior of an enhancon shell can be a time machine due to non-vanishing rotation. We link the resolution of the time machine to the recently proposed resolution of the BMPV naked singularity / ``over-rotating" geometry through the expansion of strings in the presence of RR flux. We extend the analysis to include a general class of BMPV black hole configurations, showing that any attempt to ``over-rotate" a causally sound BMPV black hole will be thwarted by the resolution mechanism. We study how it may be possible to lower the entropy of a black hole due to the non-zero rotation. This process is prevented from occurring through the creation of a family of resolving shells. The second law of thermodynamics is thereby enforced in the rotating geometry - even when there is no risk of creating a naked singularity or closed time-like curves.
Nano-based chemical sensor array systems for uninhabited ground and airborne vehicles

In a time when homemade explosive devices are being used against soldiers and in the homeland security environment, it is becoming increasingly evident that there is an urgent need for high-tech chemical sensor packages to be mounted aboard ground and air vehicles to aid soldiers in determining the location of explosive devices and the origin of bio-chemical warfare agents associated with terrorist activities from a safe distance. Current technologies utilize relatively large handheld detection systems that are housed on sizeable robotic vehicles. Research and development efforts are underway at the Army Aviation & Missile Research, Development, and Engineering Center (AMRDEC) to develop novel and less expensive nano-based chemical sensors for detecting explosives and chemical agents used against the soldier. More specifically, an array of chemical sensors integrated with an electronics control module on a flexible substrate that can conform to and be surface-mounted to manned or unmanned vehicles to detect harmful species from bio-chemical warfare and other explosive devices is being developed. The sensor system under development is a voltammetry-based sensor system capable of aiding in the detection of any chemical agent and in the optimization of sensor microarray geometry to provide nonlinear Fourier algorithms to characterize target area background (e.g., footprint areas). The status of the research project is reviewed in this paper. Critical technical challenges associated with achieving system cost, size, and performance requirements are discussed. The results obtained from field tests using an unmanned remote controlled vehicle that houses a CO2/chemical sensor, which detects harmful chemical agents and wirelessly transmits warning signals back to the warfighter, are presented. Finally, the technical barriers associated with employing the sensor array system aboard small air vehicles will be discussed.
Quantum Multiplication of Schur Polynomials

We give formulas for the products of classes of Schubert varieties in the quantum cohomology rings of Grassmannians, in terms of the combinatorics of partitions and tableaux.
Potentiometry in gas phase

In order to yield analytically useful information every potentiometric measurement requires stable and reproducible reference potential. That requirement has to be satisfied for potentiometry performed in liquid or gas phase alike, although two fundamentally different mechanisms lead to formation of the measurable cell voltage. It is shown that the Fermi level of silicon used in insulated gate field-effect transistors (IGFET) provides an exceptionally stable and robust reference potential. A semi-quantitative dependence of IGFET output on partial pressure of the analyte gas is presented.
Face Alignment by Explicit Shape Regression

We present a very efficient, highly accurate, "Explicit Shape Regression" approach for face alignment. Unlike previous regression-based approaches, we directly learn a vectorial regression function to infer the whole facial shape (a set of facial landmarks) from the image and explicitly minimize the alignment errors over the training data. The inherent shape constraint is naturally encoded into the regressor in a cascaded learning framework and applied from coarse to fine during the test, without using a fixed parametric shape model as in most previous methods. To make the regression more effective and efficient, we design a two-level boosted regression, shape indexed features and a correlation-based feature selection method. This combination enables us to learn accurate models from large training data in a short time (20 min for 2,000 training images), and run regression extremely fast in test (15 ms for a 87 landmarks shape). Experiments on challenging data show that our approach significantly outperforms the state-of-the-art in terms of both accuracy and efficiency.