cssi/SciSciGPT-SciSciNet huggingface dataset:
MIGRATION OF PLANETS EMBEDDED IN A CIRCUMSTELLAR DISK

Planetary migration poses a serious challenge to theories of planet formation. In gaseous and planetesimal disks, migration can remove planets as quickly as they form. To explore migration in a planetesimal disk, we combine analytic and numerical approaches. After deriving general analytic migration rates for isolated planets, we use N-body simulations to confirm these results for fast and slow migration modes. Migration rates scale as m –1 (for massive planets) and (1 + (e H/3)3)–1, where m is the mass of a planet and e H is the eccentricity of the background planetesimals in Hill units. When multiple planets stir the disk, our simulations yield the new result that large-scale migration ceases. Thus, growing planets do not migrate through planetesimal disks. To extend these results to migration in gaseous disks, we compare physical interactions and rates. Although migration through a gaseous disk is an important issue for the formation of gas giants, we conclude that migration has little impact on the formation of terrestrial planets.
DISCRETE LATTICE BGK BOLTZMANN EQUATION COMPUTATIONS OF TRANSIENT INCOMPRESSIBLE TURBULENT JETS

In this paper, computations of transient, incompressible, turbulent, plane jets using the discrete lattice BGK Boltzmann equation are reported. A priori derivation of the discrete lattice BGK Boltzmann equation with a spatially and temporally dependent relaxation time parameter, which is used to represent the averaged flow field, from its corresponding continuous form is given. The averaged behavior of the turbulence field is represented by the standard k–∊ turbulence model and computed using a finite-volume scheme on nonuniform grids. Computed results are compared with analytical solutions, experimental data and results of other computational methods. Satisfactory agreement is shown.
Work, Ideology, and Science: The Case of Medicine:

This article discusses the nature of work, ideology, and science in Western capitalist societies. It analyzes how capitalist or bourgeois ideology reproduces capitalist dominance in the spheres of production (Section I), politics (Section II), and science and medicine (Section III). Also, this article explains how the working class responds to that capitalist dominance through a continuous process of class struggle. Sections I, II, and II show how class struggle affects bourgeois dominance in the processes of production, politics, and science and medicine, respectively. Special focus in Section III is on the analysis of (a) how bourgeois dominance appears in science and medicine, (b) how bourgeois ideology appears and is reproduced in medical knowledge, and (c) how class struggle determines the nature of scientific and medical knowledge. In this section, an alternative mode of production of scientific and medical knowledge, different from the prevalent bourgeois one, is presented and discussed. In all thr...
Value of Histopathology in Predicting Microsatellite Instability in Hereditary Nonpolyposis Colorectal Cancer and Sporadic Colorectal Cancer

Identification of colorectal carcinomas with high levels of DNA microsatellite instability (MSI-H) is important because of the suggested prognostic and therapeutic significance associated with MSI. The role of histology in identifying MSI-H colorectal carcinomas has been suggested by some studies but not confirmed by others. Furthermore, previous studies assumed that hereditary nonpolyposis colorectal cancer (HNPCC)-associated MSI-H tumors and sporadic MSI-H tumors have similar histology. This assumption, however, has been challenged by more recent studies. In this report, we first analyzed the value of various histologic features in predicting MSI-H in a series of 218 colorectal carcinomas containing mixed HNPCC and sporadic cases [77 tumors (35%) were MSI-H by polymerase chain reaction (PCR) method]. Then, we evaluated the various histologic features comparatively in two groups extracted from the 218 cases. Group A was composed of 84 tumors from 82 patients obtained based on a strong family history (HNPCC/HNPCC-like group) (male to female ratio, 42:40; age range, 23-80 years, median, 53.5 years). Thirty-one of the 84 tumors (41.7%) were MSI-H by PCR, and all 31 cases were HNPCC by Amsterdam criteria. Group B was composed of 109 patients with no family history of colorectal cancer or HNPCC-associated cancer, obtained from surgical clinics (sporadic group) (male to female ratio, 65:69; age range, 31-84 years, median, 65 years). Thirty-five of the 109 tumors (32.1%) were MSI-H by PCR. Our results showed that, overall, poor tumor differentiation, medullary type, mucinous type, signet-ring cell component, histologic heterogeneity, and increased tumor-infiltrating lymphocytes (TILs) were features more commonly seen in MSI-H tumors than in non-MSI-H tumors. Comparative analyses showed that the overall TIL count was significantly higher in HNPCC/HNPCC-like group, and mucinous type appeared to be more frequent in HNPCC MSI-H tumors than in sporadic MSI-H tumors. However, there was no significant difference in the odds ratio for predicting MSI-H status for any of the analyzed histologic features between HNPCC/HNPCC-like group and sporadic group, indicating that differences between HNPCC and sporadic MSI-H tumors did not significantly impact on the informative value of histology in predicting MSI in the two different clinical settings. TIL counts followed by histologic heterogeneity provided the greatest sensitivity and specificity in predicting MSI status in both HNPCC/HNPCC-like and sporadic cases. Using a stepwise logistic regression model, a formula was generated that could be used to calculate the probability of a colorectal carcinoma being MSI-H based on morphologic features.
Delay between Sensing and Response in Water Contamination Events

Determining the consequences of a water contamination event is an important concern in the field of water systems security. Morbidity and mortality resulting from such a contamination are influenced in part by the amount of contaminated water consumed and the time between consumption and medical treatment. Water quality sensors in the water distribution network may shorten this time and help the users avoid the contaminant’s adverse effects by alerting authorities to unusual water quality parameters; otherwise, the authorities may first suspect contamination when the victims begin seeking treatment. Once the irregular water quality parameters have been detected, some time may still elapse before all users stop consuming the contaminated water. Modeling this additional delay is the focus of this article. This delay has been divided into five independent, sequential processes. The first phase is the amount of time required to transmit the sensed or measured contaminant concentrations to the local authoritie...
Direct comparison of the performance of CZT detectors contacted with various metals

Cadmium Zinc Telluride (CZT) achieves excellent spatial resolution and good energy resolution over the broad energy range from several keV into the MeV energy range. In this paper we present the results of a systematic study of the performance of CZT detectors manufacturered by Orbotech (before IMARAD) depending on surface preparation, contact materials and contact deposition. The standard Orbotech detectors have the dimension of 2.0×2.0×0.5 cm. They have a pixellated In anode with 8×8 pixels and a monolithic In cathode. Using the same CZT substrates several times, we have made a direct comparison of the performance of different contact materials by replacing the cathode and/or the anode contacts with several high- workfunction metals. We present the performance of the detectors and conclude with an overview over our ongoing detector optimization.
Linear and Circular Polarization Properties of Jets

I discuss the transfer of polarized synchrotron radiation in relativistic jets. I argue that the main mechanism responsible for the circular polarization properties of compact synchrotron sources is likely to be Faraday conversion and that, contrary to common expectation, a significant rate of Faraday rotation does not necessarily imply strong depolarization. The long-term persistence of the sign of circular polarization, observed in some sources, is most likely due to a small net magnetic flux generated in the central engine, carried along the jet axis and superimposed on a highly turbulent magnetic field. I show that the mean levels of circular and linear polarizations depend on the number of field reversals along the line of sight and that the gradient in Faraday rotation across turbulent regions can lead to`correlation depolarization'. The model is potentially applicable to a wide range of synchrotron sources. In particular, I demonstrate how the model can naturally explain the excess of circular over linear polarization in the Galactic Center (SgrA*) and the low-luminosity AGN M81*.
Orbit semigroups and the representation type of quivers

Abstract We show that a finite, connected quiver Q without oriented cycles is a Dynkin or Euclidean quiver if and only if all orbit semigroups of representations of Q are saturated.
Representations of reductive groups over finite rings

We discuss a cohomological construction of representations of a reductive group over the ring of power series over a finite field modulo the r-th power of the maximal ideal. The case r=1 goes back to Deligne and the author. The case where r is greater than 1 was given without proof in the author's work in 1977. Here we supply the proofs and give some further results.
American Linguistic Prescriptivism: Its Decline and Revival in the 19th Century

Aspects of nineteenth-century American life are crucial to the understanding of the history and nature of American prescriptivism. The story is not merely one of continuity from eighteenth-century Britain. An examination of linguistic thought of the nineteeth-century reveals that the prescriptive doctrine met with significant intellectual challenge from 1820 through the 40s. This reaction grew partly out of a specific revolt against rote learning, partly out of the development of national consciousness, and partly out of the ‘boundless’ intellectual tenor of the times. The thought of the period 1850 through the 70s was a significant source of the doctrine's subsequent vigor which was to exhibit a curious and remarkable continuity into and throughout the present century. During the latter half of the century the doctrine of correctness revived with new vehemence in a new drive for uniformity and conformity. This was facilitated and accommodated in general by the intellectual milieu of the time: national integration and consolidation. The single most important specific factor was the development of the genteel cultural apparatus, as manifested linguistically by an interest in language, especially in ‘linguistic etiquette’ in genteel publication; in the reaction against innovation; in the application of intellect and logic to language; in the high premium placed by the genteel on books and authority; in the anglophile tendency of the genteel; and in the desire for a responsible, stable community.
Synthesis of bis(oxydimethylene)tetrathiafulvalene (BODM-TTF) and BEDSe-TTF

Abstract Two organic donors based on the tetrathiafulvalene astructure were prepared They are bis(ethylenediseleno)-TTF (BEDSe-TTF) and bis(oxydimethylene)-TTF (BODM-TTF). Both compounds show two reversible one-electron oxidation with E1 = 0.47V and E2 = 0.87V for BEDSe-TTF and E1 = 0.35V and E2 = 0.66V for BODM-TTF. Interestingly, BODM-TTF was found to possess the lowest half-wave potentials among the known TTF derivatives.
Thick Surfaces in Hyperbolic 3-Manifolds

We show that every closed, virtually fibered hyperbolic 3-manifold contains immersed, quasi-Fuchsian.
Stereoselective Synthesis of Tetrahydrofurans via the Palladium-Catalyzed Reaction of Aryl Bromides with γ-Hydroxy Alkenes: Evidence for an Unusual Intramolecular Olefin Insertion into a Pd(Ar)(OR) Intermediate

A new, stereoselective method for the synthesis of substituted tetrahydrofurans from gamma-hydroxy alkenes that forms both a C-C and a C-O bond with diastereoselectivities of up to >20:1 is described. Initial mechanistic studies that suggest the reactions proceed via the intramolecular insertion of an olefin into a Pd(Ar)(OR) intermediate are discussed.
Linking Intermetallics and Zintl Compounds: An Investigation of Ternary Trielides (Al, Ga, In) Forming the NaZn13 Structure Type

A populous group of ternary trielide rich (Al, Ga, In) intermetallics forming the NaZn13 structure type has been synthesized from stoichiometric combinations of the elements in an arc melter. These ternary compounds have the general formula AMxT13-x, where A = Ba, Sr, La, Eu, M = Cu and Ag, and T = Al, Ga, and In, with 5 ≤ x ≤ 6.5, and have been structurally characterized by both powder and single-crystal X-ray diffraction. Furthermore, magnetic susceptibility, electrical resistivity, XPS, and EDS measurements are reported for some of the samples. Single-crystal X-ray diffraction experiments on BaCu5Al8 (BaCu5.10(7)Al7.90(7), cubic, a = 12.205(4) A, Z = 8) and EuCu6.5Al6.5 (EuCu6.41(5)Al6.59(5), cubic, a = 11.928(1) A, Z = 8) indicate that the quasi-infinite three-dimensional [CuxAl13-x] framework involves mostly Cu atoms centering icosahedra, with its vertexes randomly occupied by the remaining Cu and Al atoms. On the other hand, when M = Ag, Al shows a greater tendency to occupy the center of the icosah...
Variability of zonal currents in the eastern equatorial Indian Ocean on seasonal to interannual time scales

This study examines equatorial zonal current variations in the upper layers of eastern Indian Ocean in relation to variations in the Indian Ocean Dipole (IOD). The analysis utilizes data from the Research Moored Array for African-Asian-Australian Monsoon Analysis and Prediction (RAMA) and the European Centre for Medium-Range Weather Forecasts-Ocean Reanalysis System 4 (ECMWF-ORAS4). Surface currents are characterized by semiannual eastward flowing Wyrtki jets along the equator in boreal spring and fall, forced by westerly monsoon transition winds. The fall jet intensifies during negative IOD (NIOD) events when westerlies are anomalously strong but significantly weakens during positive IOD (PIOD) events when westerlies are anomalously weak. As zonal wind stress weakens during PIOD events, sea surface height becomes unusually low in the eastern basin and high in the west, setting up an anomalous pressure force that drives increased eastward transport in the thermocline. Opposite tendencies are evident during NIOD events in response to intensified equatorial westerlies. Current transport adjustments to anomalous zonal wind forcing during IOD events extend into the following year, consistent with the cycling of equatorial wave energy around the basin. A surface layer mass budget calculation for the eastern sea surface temperature (SST) pole of the IOD indicates upwelling of ∼2.9±0.7 Sv during normal periods, increasing by 40–50% during PIOD events and reducing effectively to zero during NIOD events. IOD-related variations in Wyrtki jet and thermocline transports are major influences on these upwelling rates and associated water mass transformations, which vary consistently with SST changes.
Melamine and Melamine-Formaldehyde Polymers as Ligands for Palladium and Application to Suzuki–Miyaura Cross-Coupling Reactions in Sustainable Solvents

The Suzuki-Miyaura cross-coupling reaction is a foundation stone of modern organic synthesis, as evidenced by its widespread use in the preparation of pharmaceuticals, agrochemicals, polymers, and other functional materials. With the prevalence of this venerable reaction in industrial synthesis, it is prudent to ensure its application adheres to the tenets of green chemistry. The introduction of cross-coupling catalysts that are active in sustainable solvents is therefore an important endeavor. In this report, a melamine-palladium complex is introduced as a versatile catalyst for the Suzuki-Miyaura cross-coupling reaction. This catalyst is soluble and active in both water and the renewable organic solvent ethyl lactate. The melamine-palladium catalyst can also be cross-linked by reaction with formaldehyde to generate an insoluble polymeric catalyst that can be recovered after the cross-coupling. The melamine-palladium system is inexpensive, easy to handle, bench-stable, and effective in catalysis in the presence of a variety of impurities (high cross-coupling yields were obtained in reactions run in unfiltered river water to illustrate this final point). Additionally, investigations reported herein revealed an intriguing relationship between catalytic efficiency and the base employed in the cross-coupling reaction. Implications for the mechanism of transmetalation in aqueous Suzuki-Miyaura cross-coupling reaction are discussed.
CRITICAL EXPONENTS OF THE 3-D ISING MODEL

We present a status report on the ongoing analysis of the 3D Ising model with nearest-neighbor interactions using the Monte Carlo Renormalization Group (MCRG) and finite size scaling (FSS) methods on 643, 1283, and 2563 simple cubic lattices. Our MCRG estimates are and ν = 0.625(1). The FSS results for Kc are consistent with those from MCRG but the value of ν is not. Our best estimate η = 0.025(6) covers the spread in the MCRG and FSS values. A surprise of our calculation is the estimate ω ≈ 0.7 for the correction-to-scaling exponent. We also present results for the renormalized coupling gR along the MCRG flow and argue that the data support the validity of hyperscaling for the 3D Ising model.
Rees algebras of conormal modules

Abstract We deal with classes of prime ideals whose associated graded ring is isomorphic to the Rees algebra of the conormal module. With such prime ideals we describe the divisor class groups of the associated graded rings. Furthermore we study the relationship between the normality of the conormal module and the completeness of components of the associated graded ring.
Satometer: how much have we searched?

We introduce Satometer, a tool that can be used to estimate the percentage of the search space actually explored by a backtrack Boolean satisfiability (SAT) solver. Satometer calculates a normalized minterm count for those portions of the search space identified by conflicts. The computation is carried out using a zero-suppressed binary decision diagram data structure and can have adjustable accuracy. The data provided by Satometer can help diagnose the performance of SAT solvers and can shed light on the nature of a SAT instance.
Type elaboration and subtype completion for Java bytecode

Java source code is strongly typed, but the translation from Java source to bytecode omits much of the type information originally contained within methods. Type elaboration is a technique for reconstructing strongly typed programs from incompletely typed bytecode by inferring types for local variables. There are situations where, technically, there are not enough types in the original type hierarchy to type a bytecode program. Subtype completion is a technique for adding necessary types to an arbitrary type hierarchy to make type elaboration possible for all verifiable Java bytecode. Type elaboration with subtype completion has been implemented as part of the Marmot Java compiler.
Dependence of the structure of the Northern Hemisphere annular mode on the polarity of ENSO

[1] The structure of the Northern Hemisphere annular mode (NAM) is shown to be significantly different during warm and cold winters of the ENSO cycle. During warm winters the Arctic center of action of the annular mode is more prominent and extends deeper into Siberia, its related surface air temperature signal is stronger, and the compensating outer ring in the sea-level pressure field is much broader, encompassing the entire tropics. During cold winters the NAM signature is much more pronounced over the Pacific sector: the sea-level pressure pattern exhibits a North Pacific center of action, positively correlated with the Atlantic center, and pronounced deflections of the storm track are also evident. It is suggested that the former features are associated with the equatorward displacement of the jet stream and the storm tracks during warm winters of the ENSO cycle and the latter is related to the the more pronounced break in the subtropical jet stream over the Pacific sector during cold winters.
Expected asymptotically optimal planar point location

Given a fixed distribution of point location queries among the triangles in a triangulation of the plane, a data structure is presented that achieves, within constant multiplicative factors, the entropy bound on the expected point location query time. The data structure is a simple variation of Kirkpatrick's classic planar point location structure [D.G. Kirkpatrick, SIAM J. Comput. 12 (1) (1983) 28-35], and has linear construction costs and space requirements.
Lower Bounds for Randomized Exclusive Write PRAMs

In this paper we study the question: How useful is randomization in speeding up Exclusive Write PRAM computations? Our results give further evidence that randomization is of limited use in these types of computations. First we examine a compaction problem on both the CREW and EREW PRAM models, and we present randomized lower bounds which match the best deterministic lower bounds known. (For the CREW PRAM model, the lower bound is asymptotically optimal.) These are the first nontrivial randomized lower bounds known for the compaction problem on these models. We show that our lower bounds also apply to the problem of approximate compaction. Next we examine the problem of computing boolean functions on the CREW PRAM model, and we present a randomized lower bound which improves on the previous best randomized lower bound for many boolean functions, including the OR function. (The previous lower bounds for these functions were asymptotically optimal, but we improve the constant multiplicative factor.) We also give an alternate proof for the randomized lower bound on PARITY, which was already optimal to within a constant additive factor. Lastly, we give a randomized lower bound for integer merging on an EREW PRAM which matches the best deterministic lower bound known. In all our proofs, we use the Random Adversary method, which has previously only been used for proving lower bounds on models with Concurrent Write capabilities. Thus this paper also serves to illustrate the power and generality of this method for proving parallel randomized lower bounds.
Thin metal film characterization and chemical sensors: monitoring electronic conductivity, mass loading and mechanical properties with surface acoustic wave devices

Abstract Acoustoelectric coupling between charge carriers in a thin metal film and the evanescent electric field associated with a surface acoustic wave (SAW) propagating along the surface of a piezoelectric substrate provides a unique interaction mechanism with which to study the film's electronic charfe transport properties, as well as changes in these properties resulting from chemisorption from the gas phase. We utilized 97 MHz ST-cut quartz- and 32 MHz Y-cut LiNbO 3 -based SAW devices to follow (1) the process of vacuum deposition of thin metal films (5–500 A), (2) the (room temperature) relaxation of such films after their deposition, and (3) the chemisorption-induced changes in both the mass density and electrical conductivity of such films. Changes in mass density were followed with a resolution exceeding 1% of a monolayer. Sheet conductivity measurements made with the 97 MHz SAW device correlated well with simultaneous measurements made with a d.c. electrometer. In addition, changes in the mechanical properties of freshly deposited thin films were observed during relaxation and when gaseous species interact with them; we believe this is a result of adsorption predominantly along grain boundaries. The combination of responses to three different physical parameters can be utilized in the design of chemical sensors.
Forecasting Structural Change With a Regional Econometric Input-Output Model

The sophistication of regional economic models has been demonstrated in numerous ways, most recently in the form of linking several modeling systems or in the expansion in the number of equations that can be manipulated successfully to produce impact analyses or forecasts. In this paper, an alternative perspective is employed. What do regional macro-level forecasts indicate about the process of structural change? A new methodology is illustrated that enables analysts to make forecasts of detailed structural change in the interindustry relations in an economy. Using a regional econometric input-output model developed for the Chicago metropolitan region, derived input-output tables are extracted for the period 1975–2016. These tables are then analyzed to determine the forecasted direction of structural changes for the region. The innovation illustrated here is based on a model that exploits the general equilibrium spirit of computable general equilibrium models through the adjustment of input coefficients to clear markets.
Ideology and Prejudice The Role of Value Conflicts

In three studies, we tested whether prejudice derives from perceived similarities and dissimilarities in political ideologies (the value-conflict hypothesis). Across three diverse samples in Study 1, conservatives had less favorable impressions than liberals of groups that were identified as liberal (e.g., African Americans, homosexuals), but more favorable impressions than liberals of groups identified as conservative (e.g., Christian fundamentalists, businesspeople). In Studies 2 and 3, we independently manipulated a target’s race (European American or African American) and political attitudes (liberal or conservative). Both studies found symmetrical preferences, with liberals and conservatives each liking attitudinally similar targets more than dissimilar targets. The amount of prejudice was comparable for liberals and conservatives, and the race of the target had no effect. In all three studies, the same patterns were obtained even after controlling for individual differences on prejudice-related dime...
Stable gold( III ) catalysts by oxidative addition of a carbon–carbon bond

Low-valent late transition-metal catalysis has become indispensable to chemical synthesis, but homogeneous high-valent transition-metal catalysis is underdeveloped, mainly owing to the reactivity of high-valent transition-metal complexes and the challenges associated with synthesizing them. Here we report a carbon-carbon bond cleavage at ambient conditions by a Au(i) complex that generates a stable Au(iii) cationic complex. In contrast to the well-established soft and carbophilic Au(i) catalyst, this Au(iii) complex exhibits hard, oxophilic Lewis acidity. For example, we observed catalytic activation of α,β-unsaturated aldehydes towards selective conjugate additions as well as activation of an unsaturated aldehyde-allene for a [2 + 2] cycloaddition reaction. The origin of the regioselectivity and catalytic activity was elucidated by X-ray crystallographic analysis of an isolated Au(iii)-activated cinnamaldehyde intermediate. The concepts revealed suggest a strategy for accessing high-valent transition-metal catalysis from readily available precursors.
Dual string pairs with N = 1 and N = 2 supersymmetry in four dimensions

Based on a simple adiabatic argument and by considering the heterotic string counterpart of certain symmetries of Type II superstrings such as (-1) FL and orientation reversal, we construct orbifold candidates for dual pairs of heterotic and Type II string theories with N = 2 and N = 1 supersymmetry. We also analyze from a similar point of view the K3 fibrations that enter in recently proposed N = 2 candidates and use this structure together with certain orientation-reversing symmetries to construct N = 1 dual pairs. These pairs involve generalizations of Type I vacua which can be equivalent to E 8 × E 8 heterotic strings, while standard Type I vacua are related to SO (32).
The Surface Heat Flux as a Function of Ground Cover for Climate Models

Abstract Surface heat fluxes were examined as a function of surface properties and meteorological conditions in a 100 km × 100 km grid square at 1-km spatial resolution centered at the location of the First ISLSCP (International Satellite Land Surface Climatology Project) Field Experiment (FIFE), the Forest Ecosystem Dynamics site in central Maine, and a semiarid rangeland site around Walnut Gulch, Arizona. This investigation treats the surface heat flux variability within a GCM grid box to provide insight into methods for treating that variability in climate models. The heat fluxes were calculated using NOAA AVHRR and available meteorological data. The average heat fluxes that were estimated using the various area ground-cover representations were compared with the ensemble average heat fluxes for the entire area, which were assumed to be the best representation of the heat fluxes for the areas. Average heat fluxes were estimated for the entire 100 km × 100 km area based on a single ground-cover represen...
A Mutation in the Human Uncoordinated 119 Gene Impairs TCR Signaling and is Associated with CD4 Lymphopenia.

Idiopathic CD4 lymphopenia (ICL) is an immunodeficiency disorder of unclear etiology. Here we describe a heterozygous dominant-negative missense mutation (codon 22 GGC→GTC; V22G) of the signaling adaptor protein Uncoordinated 119 (Unc119) in an ICL patient. The patient is a 32-year-old female with < 300 CD4 T cells/μL and with a history of recurrent sinusitis/otitis media, frequent episodes of shingles, a widespread fungal nail infection, fungal dermatitis, oral herpetic lesions, and bronchiolitis obliterans organizing pneumonia after 2 episodes of bacterial pneumonia. The patient's cells have reduced response to TCR stimulation, with impairment in both localization and enzymatic activation of the lymphocyte-specific kinase (Lck) resulting in decreased cell proliferation. Transduction of the mutant Unc119 but not wild-type Unc119 into normal T cells reproduces the signaling and proliferation defects. The mutation disrupts the Unc119-Lck interaction which is normally needed for stimulation of the Lck catalytic activity by TCR. The mutant protein also causes mislocalization of Lck to Rab11+ perinuclear endosomes. The mutation is not present in 2 other patients with ICL, patients with secondary CD4 lymphopenia or 60 healthy subjects. The V22G mutation of Unc119 represents a novel genetic defect in ICL.
The turbulent recirculating flow field in a coreless induction furnace. A comparison of theoretical predictions with measurements

A mathematical representation for the electromagnetic force field and the fluid flow field in a coreless induction furnace is presented. The fluid flow field was represented by writing the axisymmetric turbulent Navier-Stokes equation, containing the electromagnetic body force term. The electromagnetic body force field was calculated by using a technique of mutual inductances. The kappa-epsilon model was employed for evaluating the turbulent viscosity and the resultant differential equations were solved numerically. Theoretically predicted velocity fields are in reasonably good agreement with the experimental measurements reported by Hunt and Moore; furthermore, the agreement regarding the turbulent intensities are essentially quantitative. These results indicate that the kappa-epsilon model provides a good engineering representation of the turbulent recirculating flows occurring in induction furnaces. At this stage it is not clear whether the discrepancies between measurements and the predictions, which were not very great in any case, are attributable either to the model or to the measurement techniques employed.
Perception of 3D spatial relations for 3D displays

We test perception of 3D spatial relations in 3D images rendered by a 3D display (Perspecta from Actuality Systems) and compare it to that of a high-resolution flat panel display. 3D images provide the observer with such depth cues as motion parallax and binocular disparity. Our 3D display is a device that renders a 3D image by displaying, in rapid succession, radial slices through the scene on a rotating screen. The image is contained in a glass globe and can be viewed from virtually any direction. In the psychophysical experiment several families of 3D objects are used as stimuli: primitive shapes (cylinders and cuboids), and complex objects (multi-story buildings, cars, and pieces of furniture). Each object has at least one plane of symmetry. On each trial an object or its "distorted" version is shown at an arbitrary orientation. The distortion is produced by stretching an object in a random direction by 40%. This distortion must eliminate the symmetry of an object. The subject's task is to decide whether or not the presented object is distorted under several viewing conditions (monocular/binocular, with/without motion parallax, and near/far). The subject's performance is measured by the discriminability d ', which is a conventional dependent variable in signal detection experiments.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
High Speed Video Techniques With Ccd-Cameras

The application of CCD-TV-cameras to high speed techniques is presently limited by the speed of the serial signal read out. Many CCD-Sensors are constructed using the frame transfer technique. Then it is possible to take two pictures within a time interval of about 400 μs. The electronical storage of a picture on the CCD make other applications possible. On is the use of stroboscopic illumination. Another possibility is the electronical Cranz-Schardin-Camera. The third application described in this paper is a CCD streak camera. In this camera the exposure is necessary during the fast frame transfer from the lightsensing area to the memory of the device. The time resolution was 1.6 μs with standard driver circuits and can be faster with high current shift pulses. Furthermore, a reduction of the frame size makes high speed sequences possible.
Vortex dynamics and correlated disorder in high-Tc superconductors

We develop a theory for the vortex motion in the presence of correlated disorder in the form of twin boundaries and columnar defects. Mapping vortex trajectories onto boson world lines enables us to establish the duality of the vortex transport in systems with correlated disorder and the hopping conductivity of charged particles in 2D systems. A glassy-like dynamics of the vortex lines with zero linear resistivity and strongly nonlinear current-voltage behavior as V ∝ exp(-const/Jμ) in a Bose glass state is predicted.
Off-axis electron orbits in realistic helical wigglers for free-electron-laser applications

Off-axis electron orbits in free-electron-laser beams of finite thickness, subjected to combined helical wiggler and axial guide fields, have been studied analytically. A semiempirical equation for the electron velocity components, averaged over the electron's oscillatory (betatron) motion, has been derived as a function of the radial displacement of the electron guiding center. The predictions from the equation are compared with single-particle numerical simulations, and with free-electron-laser experiments. Good agreement is found.
A Lower Bound for the Canonical Height Associated to a Drinfeld Module

Denis associated to each Drinfeld module M over a global function function field L a canonical height function, which plays a role analogous to that of the Neron-Tate height in the context of elliptic curves. We prove that there exist constants \epsilon>0 and C, depending only on the number of places at which M has bad reduction, such that either x in M is a torsion point of bounded order, or else the canonical height of x is bound below by \epsilon max{h(j_M), deg(D_M)}, where j_M is a certain invariant of the isomorphism class of M, and D_M is the minimal discriminant of M. As an application, we make some observations about specializations of one-parameter families of Drinfeld modules.
The Mass and Radius of the Neutron Star in 4U 1820-30

We report on the measurement of the mass and radius of the neutron star in the low-mass X-ray binary 4U 1820-30. The analysis of the spectroscopic data on multiple thermonuclear bursts yields well-constrained values for the apparent emitting area and the Eddington flux, both of which depend in a distinct way on the mass and radius of the neutron star. The distance to the source is that of the globular cluster NGC 6624, where the source resides. Combining these measurements, we uniquely determine the probability density over the stellar mass and radius. We find the mass to be M = 1.58 {+-} 0.06 M{sub sun} and the radius to be R = 9.1 {+-} 0.4 km.
Closing the generation gap

The author has explained how the naive obstructions to unifying vacua with different net generation numbers can be overcome, and she gave a class of examples of chirality-changing phase transitions in four dimensions. The phenomenon exhibited here presumably occurs quite generally; it would be very interesting to understand whether in fact one can connect all vacua with N {le} 1 supersymmetry at low energies. For this an F-theory analysis could be quite instructive, once that approach is developed more fully for four-folds. Perhaps the next in principle question to ask along these lines is whether there could be any physical process which changes the number of supersymmetries.
The vogue of revolution in poor countries

In the aftermath of World War II, a surprisingly large number of poor countries were upset by revolution: Vietnam, China, Cuba, Algeria, Ethiopia, Cambodia, Mozambique, Angola, Afghanistan, Iran, and Nicaragua. Revolutionaries in these geographically and culturally disparate countries came to power through different routes, but once in power they had remarkably similar ideas about how to remake their states and societies. In this analysis of the course of these revolutions, the author suggests that shared institutional and policy choices of revolutionary elites arose from a fashionable political imagination. Paradoxically, in an era marked by the demise of European colonialism, it was Europeans - mainly Marx, Engels, and Lenin - who supplied the vision of what could replace colonialism. Colburn traces the diffusion of this intoxicating political imagination not to the Soviet Union, but instead to Western Europe and North America, where socialism was rarely more than political fantasy. In Latin America, the Middle East, Africa, and Asia, this imagination inspired revolution, but more importantly led to sadly flawed ideas about how to eliminate poverty and inequality. The vogue for revolution in poor countries withered away in a descent accelerated, but not initiated, by the East European events of 1989-1991. This lucid book clarifies why so many countries were so profoundly wrecked in the frenzied pursuit of a dreamt-up world.
Mesoscopic ferromagnet-superconductor junctions and the proximity effect

We have measured the electrical transport of submicron ferromagnets (Ni) in contact with a mesoscopic superconductor (Al) for a range of interface resistances. In the geometry measured, the interface and the ferromagnet are measured separately. The ferromagnet itself shows no appreciable superconducting proximity effect, but the ferromagnet/superconductor interface exhibits strong temperature, field, and current bias dependences. These effects are dependent on the local magnetic field distribution near the interface arising from the ferromagnet. We find that the temperature dependences can be qualitatively described by a modified version of the Blonder-Tinkham-Klapwijk theory for normal-superconductor transport.
Internalizing Neighborhood Externalities: The Effect of Subdivision Size and Zoning on Residential Lot Prices

Abstract Though land-development regulations potentially control neighborhood externalities, the developer of a residential subdivision contributes to that control by developing a larger parcel of land. This paper reports estimates of the effect of parcel size on the sale price of developed building lots. The results indicate that adding an acre to the median development increases lot prices by about 3%. Amenities appear to be income normal, and the return to parcel size is greater in unincorporated areas, perhaps due to less intensive governmental control over externalities.
Low-Diffusion Flux-Splitting Methods for Flows at All Speeds

Methods for extending the advective upwind splitting method (AUSM) family of low-diffusion flux-splitting schemes to operate effectively at all flow speeds are developed. The extensions developed are designed for use with time-derivative preconditioning and are based on the idea that the speed of sound should cease to be an important scaling parameter for the diffusive contributions to the interface flux as the Mach number becomes small. Using this criterion, alternative definitions for the interface Mach numbers are developed, and methods for ensuring pressure-velocity coupling at low speeds are formulated. Results are presented for inviscid flows through a channel at various Mach numbers, developing viscous flow in a two-dimensional duct, driven-cavity flows at various Mach and Reynolds numbers, flow over a backward-facing step, and hydrogen-nitrogen mixing layers
Experimental Test of the Sweet-Parker Model of Magnetic Reconnection

We report a quantitative experimental test of the Sweet-Parker model of magnetic reconnection in a controlled laboratory plasma. It is found that the observed reconnection rate cannot be explained by the Sweet-Parker model unless the model is generalized to incorporate compressibility, downstream pressure, and the effective resistivity. The latter is significantly enhanced over its classical values in the collisionless limit.
Exploring Halo Substructure with Giant Stars: A Diffuse Star Cloud or Tidal Debris around the Milky Way in Triangulum‐Andromeda

We report here the discovery of an apparent excess of 2MASS M giant candidates with dereddened 0.85 b > -40° and covering most of the constellations of Triangulum and Andromeda. This structure does not seem to be preferentially distributed around a clear core, but rather lies in a tenuous, clumpy cloudlike structure tens of kiloparsecs away. The reduced proper-motion diagram, as well as spectroscopy of a subsample, shows these excess stars to be real giants, not contaminating dwarfs. Radial velocity measurements indicate among those M giants the presence of a coherent kinematical structure with a velocity dispersion σ < 17 km s-1. Our findings support the existence of a quite dispersed stellar structure around the Milky Way that, because of its coreless and sparse distribution, could be part of a tidal stream or a new kind of satellite galaxy.
Hopf Algebras of Heap Ordered Trees and Permutations

A standard heap ordered tree with n + 1 nodes is a finite rooted tree in which all the nodes except the root are labeled with the natural numbers between 1 and n, and that satisfies the property that the labels of the children of a node are all larger than the label of the node. Denote the set of standard heap ordered trees with n + 1 nodes by &#x1d4af; n . Let It is known that there are Hopf algebra structures on k &#x1d4af;. Let &#x1d516; n denote the symmetric group on n symbols. Let We give a bialgebra structure on k&#x1d516;, and show that there is a natural bialgebra isomorphism from k&#x1d4af; to k&#x1d516;.
Further evidence on the asymmetric behavior of unemployment rates over the business cycle

Abstract Sichel recently reported that Neftci's claim to have found evidence in favor of asymmetry in the quarterly aggregate unemployment rate was based on an error. Using a modified version of Neftci's test, this paper is the first to report evidence of such asymmetry using a Markov procedure. The test is then applied to a group of quarterly sectoral unemployment rates. The results suggest that the primary source of asymmetry in the aggregate unemployment rate is the cyclical behavior of the unemployment rate in the manufacturing sector.
Aeronomy of extra-solar giant planets at small orbital distances

Abstract One-dimensional aeronomical calculations of the atmospheric structure of extra-solar giant planets in orbits with semi-major axes from 0.01 to 0.1 AU show that the thermospheres are heated to over 10,000 K by the EUV flux from the central star. The high temperatures cause the atmosphere to escape rapidly, implying that the upper thermosphere is cooled primarily by adiabatic expansion. The lower thermosphere is cooled primarily by radiative emissions from H+3, created by photoionization of H2 and subsequent ion chemistry. Thermal decomposition of H2 causes an abrupt change in the composition, from molecular to atomic, near the base of the thermosphere. The composition of the upper thermosphere is determined by the balance between photoionization, advection, and H+ recombination. Molecular diffusion and thermal conduction are of minor importance, in part because of large atmospheric scale heights. The energy-limited atmospheric escape rate is approximately proportional to the stellar EUV flux. Although escape rates are large, the atmospheres are stable over time scales of billions of years.
Scalar absorption by noncommutative D3-branes

The classical cross section for low energy absorption of the RR-scalar by a stack of noncommutative D3-branes in the large NS B-field limit is calculated. In the spirit of AdS/CFT correspondence, this cross section is related to two point function of a certain operator in noncommutative Yang-Mills theory. Compared at the same gauge coupling, the result agrees with that of obtained from ordinary D3-branes. This is consistent with the expectation that ordinary and noncommutative Yang-Mills theories are equivalent below the noncommutativity scale, but it is a nontrivial prediction above this scale.
Transgenic expression and purification of myosin isoforms using the Drosophila melanogaster indirect flight muscle system

Biophysical and structural studies on muscle myosin rely upon milligram quantities of extremely pure material. However, many biologically interesting myosin isoforms are expressed at levels that are too low for direct purification from primary tissues. Efforts aimed at recombinant expression of functional striated muscle myosin isoforms in bacterial or insect cell culture have largely met with failure, although high level expression in muscle cell culture has recently been achieved at significant expense. We report a novel method for the use of strains of the fruit fly Drosophila melanogaster genetically engineered to produce histidine-tagged recombinant muscle myosin isoforms. This method takes advantage of the single muscle myosin heavy chain gene within the Drosophila genome, the high level of expression of accessible myosin in the thoracic indirect flight muscles, the ability to knock out endogenous expression of myosin in this tissue and the relatively low cost of fruit fly colony production and maintenance. We illustrate this method by expressing and purifying a recombinant histidine-tagged variant of embryonic body wall skeletal muscle myosin II from an engineered fly strain. The recombinant protein shows the expected ATPase activity and is of sufficient purity and homogeneity for crystallization. This system may prove useful for the expression and isolation of mutant myosins associated with skeletal muscle diseases and cardiomyopathies for their biochemical and structural characterization.
Arylazo dyes containing a built-in hindered-amine moiety

Abstract This paper describes the synthesis, spectral properties, and photolytic behavior of some 5-arylazo-6-hydroxy-y-carbolines. Like 1-arylazo-2-naphthols, these novel dyes exist primarily in the hydrazone form. Interestingly, however, the arylazo-γ-carboline dyes are significantly more light-stable in a polymer matrix than their 1-arylazo-2-naphthol counterparts. This suggests that the use of a built-in hindered-amine residue is an effective way to inhibit the lightinduced oxidation of arylhydrazone-type dyes. The preparation of novel nitroxide derivatives of the arylazo-γ-carbolines for electron spin resonance spin-probe studies is also described.