cssi/SciSciGPT-SciSciNet huggingface dataset:
Stereoselective elaboration of side chain residues in cyclopropane-containing dipeptide isosteres

A variety of alkyl, substituted alkyl, and aryl side chain residues in cyclopropane-containing dipeptide isosteres were introduced by the highly diastereoselective (dr ≥20:1) additions of transformed into the corresponding N-Boc-protected amines with little or no stereochemical erosion. organolithium or Grignard reagents to N, N-dimethylhydrazone 6. The resulting hydrazines were
A classification for 2-isometries of noncommutative LP-spaces

In this paper we extend previous results of Banach, Lamperti and Yeadon on isometries ofLp-spaces to the non-tracial case first introduced by Haagerup. Specifically, we use operator space techniques and an extrapolation argument to prove that every 2-isometryT:Lp(M) →Lp(N) between arbitrary noncommutativeLp-spaces can always be written in the form\(T(\phi ^{\frac{1}{p}} ) = w(\phi o \pi ^{ - 1} o {\rm E})^{\frac{1}{p}} , \phi \in \mathcal{M}_ * ^ + \) Here π is a normal *-isomorphism fromM onto the von Neumann subalgebra π(M) ofN,w is a partial isometry inN, andE is a normal conditional expectation fromN onto π(M). As a consequence of this, any 2-isometry is automatically a complete isometry and has completely contractively complemented range.
Inorganic arsenic and human prostate cancer

We critically evaluated the etiologic role of inorganic arsenic in human prostate cancer. We assessed data from relevant epidemiologic studies concerning environmental inorganic arsenic exposure. Whole animal studies were evaluated as were in vitro model systems of inorganic arsenic carcinogenesis in the prostate. Multiple studies in humans reveal an association between environmental inorganic arsenic exposure and prostate cancer mortality or incidence. Many of these human studies provide clear evidence of a dose-response relationship. Relevant whole animal models showing a relationship between inorganic arsenic and prostate cancer are not available. However, cellular model systems indicate arsenic can induce malignant transformation of human prostate epithelial cells in vitro. Arsenic also appears to impact prostate cancer cell progression by precipitating events leading to androgen independence in vitro. Available evidence in human populations and human cells in vitro indicates that the prostate is a target for inorganic arsenic carcinogenesis. A role for this common environmental contaminant in human prostate cancer initiation and/or progression would be very important.
Construction of commuting difference operators for multiplicity free spaces

The analysis of invariant differential operators on certain multiplicity free spaces led recently to the introduction of a family of symmetric polynomials that is more general than Jack polynomials (see [KS], but also [OO1], [OO2]). They are called interpolation Jack polynomials, shifted Jack polynomials, or Capelli polynomials. Apart from being inhomogeneous, they are distinguished from classical Jack polynomials by their very simple definition in terms of vanishing conditions. One of the most important and non-obvious properties of Capelli polynomials is that they are eigenfunctions of certain explicitly given difference (as opposed to differential) operators (see [KS]). This readily implies that their top homogeneous term is in fact a (classical) Jack polynomial. Other consequences include a binomial theorem, a Pieri formula, and much more. It is well-known that Jack polynomials are tied to root systems of type A and that they have natural analogues for other root systems (see e.g., [He]). Therefore, it is a natural problem as to whether this holds for the Capelli polynomials as well. Okounkov [Ok] proposed such an analogue for root systems of type BC and proved that these share some of the nice properties of Capelli polynomials. But, unfortunately, Okounkov’s polynomials do not satisfy difference equations. Also their representation-theoretic significance is not clear. In this paper we go back to the origin and let ourselves be guided by the theory of multiplicity free actions. It is known (see section 7 for details) that these actions give rise to combinatorial structures consisting of four data (Γ,Σ,W, l). Here Γ is a lattice, Σ ⊂ Γ a basis, W ⊆ AutΓ a finite reflection group, and l ∈ Γ some element. These data alone suffice to formulate the definition of a (generalized) Capelli polynomial but, in that generality, neither existence nor uniqueness will hold, let alone any other good property.
Cardiac rehabilitation in the elderly

Rehabilitation for patients with heart disease consists of exercise training, behavioral interventions, counseling, and education with the goal of improving physiologic and psychosocial status. The Cardiac Rehabilitation Clinical Practice Guidelines, recently published in the United States, list the most substantial benefits of cardiac rehabilitation as an improvement in exercise tolerance, symptoms, blood lipid levels, and psychosocial well-being, and a reduction in cigarette smoking, stress, and mortality. With the evidence-base on the elderly in the Guidelines derived from 1 non-randomized controlled trial and 7 observational studies, the efficacy and effectiveness of cardiac rehabilitation is based almost exclusively on data generated on young and middle-aged males. We have located an additional 10 randomized and 2 non-randomized controlled trials published since the Guidelines, but only one provided age-specific data. The elderly are the fastest growing segment of the population, and may be more responsive to the effects of cardiac rehabilitation as they often have greater initial disability and less independence than younger patients. While referral of elderly persons to cardiac rehabilitation services appears safe and warranted in the secondary prevention of heart disease, the lack of rigorous scientific evidence has created an important clinical research and clinical policy vacuum which urgently needs to be filled.
A disaggregated approach to test the J-Curve phenomenon: Japan versus her major trading partners

A limited number of studies have tested the J-Curve phenomenon using bilateral trade data between the United States and its major trading partners. In this paper, we test the J-Curve hypothesis by using quarterly bilateral data over the 1973–98 period between Japan and its nine major trading partners. We demonstrate that when aggregate data are used, there is no evidence of the J-Curve in the short run or any significant relation between trade balance and effective exchange rate in the long run. However, when bilateral data are employed, we find evidence of the J-Curve between Japan and Germany as well as between Japan and Italy. We also find that real depreciation of the yen has favorable long-run effects in the cases of Canada, the United Kingdom, and the United States.
Highly diastereo- and enantioselective additions of homoenolates to nitrones catalyzed by N-heterocyclic carbenes.

The diastereo- and enantioselective addition of N-heterocyclic carbene-generated homoenolates to nitrones is reported. This formal [3 + 3] addition of α,β-unsaturated aldehydes and nitrones generates unusual morpholinone heterocycles which are converted into γ-hydroxy amino esters by addition of methanol to the reaction. The use of a chiral N-heterocyclic carbene (NHC) as the catalyst provides the amino esters in high diastereoselectivity (up to 20:1 dr) and enantioselectivity (up to 94%). The process accommodates α,β-unsaturated aldehydes with β-alkyl and β-aryl substituents. The γ-hydroxy amino esters can be converted to optically enriched γ-lactams by a two-step procedure involving mild reduction of the N−O bond and acid-catalyzed amide formation.
Vinylogous Mannich reactions. Stereoselective formal synthesis of pumiliotoxin 251D

Abstract A concise synthesis of (−)-3, a known precursor of pumiliotoxin 251D, has been completed using a vinylogous Mannich reaction as a key construction. Silyloxyfuran 10 added to methoxypyrrolidine 20 in the presence of TMS-OTf to give a mixture (4.8:1) of 21 and 22 in 57% yield. Reduction and global deprotection of 21 afforded the bicyclic lactam 23. Raney Nickel mediated extrusion of the hydroxymethyl group from 23 gave (−)-3.
Rapid solid-state synthesis of binary group 15 chalcogenides using microwave irradiation

Abstract Solid-state microwave synthesis was found to provide a simple, rapid and economical route to prepare Sb2Se3, Sb2Te3, Bi2Se3 and Bi2Te3. These technologically important materials were prepared via solid-state microwave synthesis in as little as 4 min. Through the process of finding the ideal synthetic conditions with which to produce each of these compounds, the effects that several synthetic variables have on the reaction outcomes were explored. Scanning electron microscopy, energy dispersive spectroscopy, powder X-ray diffraction, differential thermal analysis and diffuse reflectance measurements, when appropriate, were used to characterize the materials.
Rapid Formation of Gas Giant Planets around M Dwarf Stars

Extrasolar planet surveys have begun to detect gas giant planets in orbit around M dwarf stars. While the frequency of gas giant planets around M dwarfs so far appears to be lower than that around G dwarfs, it is clearly not zero. Previous work has shown that the core accretion mechanism does not seem to be able to form gas giant planets around M dwarfs, because the time required for core formation scales with the orbital period, which lengthens for lower mass stars, resulting in failed (gas-poor) cores unless the gaseous protoplanetary disk survives for >10 Myr. Disk instability, on the other hand, is rapid enough (~103 yr) that it should be able to form gas giant protoplanets around even low-mass stars well before the gaseous disk disappears. A new suite of three-dimensional, radiative, gravitational hydrodynamical models is presented that calculates the evolution of initially marginally gravitationally unstable disks with masses of 0.021-0.065 M☉ orbiting around stars with masses of 0.1 and 0.5 M☉, respectively. The models show that gas giant planets are indeed likely to form by the disk instability mechanism in orbit around M dwarf stars, the opposite of the prediction for formation by the core accretion mechanism. This difference offers another observational test for discriminating between these two theoretical end members for giant planet formation. Ongoing and future extrasolar planet searches around M dwarfs by spectroscopy, microlensing, photometry, and astrometry offer the opportunity to help decide between the dominance of the two mechanisms.
Turbulence in the Outer Regions of Protoplanetary Disks. I. Weak Accretion with no Vertical Magnetic Flux

We use local numerical simulations to investigate the strength and nature of magnetohydrodynamic (MHD) turbulence in the outer regions of protoplanetary disks, where ambipolar diffusion is the dominant non-ideal MHD effect. The simulations include vertical stratification and assume zero net vertical magnetic flux. We employ a super time-stepping technique to ameliorate the Courant restriction on the diffusive time step. We find that in idealized stratified simulations, with a spatially constant ambipolar Elsasser number Am, turbulence driven by the magnetorotational instability (MRI) behaves in a similar manner as in prior unstratified calculations. Turbulence dies away for Am ? 1, and becomes progressively more vigorous as ambipolar diffusion is decreased. Near-ideal MHD behavior is recovered for Am ? 103. In the intermediate regime (10 ? Am ? 103) ambipolar diffusion leads to substantial increases in both the period of the MRI dynamo cycle and the characteristic scales of magnetic field structures. To quantify the impact of ambipolar physics on disk accretion, we run simulations at 30 AU and 100 AU that include a vertical Am profile based upon far-ultraviolet (FUV) ionized disk models. These models develop a vertically layered structure analogous to the Ohmic dead zone that is present at smaller radii. We find that, although the levels of surface turbulence can be strong (and consistent with constraints on turbulent line widths at these radii), the inferred accretion rates are at least an order of magnitude smaller than those observed in T Tauri stars. This discrepancy is very likely due to the assumption of zero vertical magnetic field in our simulations and suggests that vertical magnetic fields are essential for MRI-driven accretion in the outer regions of protoplanetary disks.
Carbon leakage: the role of sequential policy setting

We analyze non-cooperative environmental policy when the only strategic interaction between countries is through bilateral transboundary pollution, i.e., countries are closed or small open economies. Under simultaneous moves, there is no carbon leakage. However, in the sequential-move game, carbon leakage occurs; the leader sets its pollution tax lower than that in the simultaneous-move game and lower than the marginal damage from own pollution, while the follower sets its tax higher than that in the simultaneous-move game. The only motive behind the leader's underregulation of own pollution is to reduce the incidence of transboundary pollution from the follower. If pollution is a pure global public bad, aggregate pollution is higher in the sequential-move game than in the simultaneous-move game. The leader (follower) obtains higher (lower) welfare than that under simultaneous moves. Hence, if countries can choose to be leaders or followers, they choose to move first to set environmental taxes.
Dust settling in magnetorotationally driven turbulent discs – I. Numerical methods and evidence for a vigorous streaming instability

In this paper, we have used the riemann code for computational astrophysics to study the interaction of a realistic distribution of dust grains with gas at specific radial locations in a vertically stratified protostellar accretion disc. The disc was modelled to have the density and temperature of a minimum mass solar nebula, and shearing box simulations at radii of 0.3 and 10 au are reported here. The disc was driven to a fully developed turbulence via the magnetorotational instability (MRI). The simulations span three gas scaleheights about the disc's midplane. We find that the inclusion of standard dust-to-gas ratios does not have any significant effect on the MRI even when the dust sediments to the midplane of the accretion disc. The density distribution of the dust of all sizes reached a Gaussian profile within two scaleheights of the disc's midplane. The vertical scaleheights of these Gaussian profiles are shown to be proportional to the reciprocal of the square root of the dust radius when large spherical dust grains are considered. This result is consistent with theoretical expectation. The largest two families of dust in one of our simulations show a strong tendency to settle to the midplane of the accretion disc. The large dust tends to organize itself into elongated clumps of high density. The dynamics of these clumps is shown to be consistent with a streaming instability. The streaming instability is seen to be very vigorous and persistent once it forms. Each stream of high-density dust displays a reduced rms velocity dispersion. The velocity directions within the streams are also aligned relative to the mean shear, providing further evidence that we are witnessing a streaming instability. The densest clumpings of large dust are shown to form where the streams intersect. We have also shown that the mean free path and collision time for dust that participates in the streaming instability are reduced by almost two orders of magnitude relative to the average mean free paths and collision times. The rms velocities between the grains also need to fall below a minimum threshold in order for the grains to stick and we show that a small amount of the large dust in our 10 au simulation should have a propensity for grain coalescence. The results of our simulations are likely to be useful for those who model spectral energy distributions of protostellar discs and also for those who model dust coagulation and growth.
Critical Inquiry into Urban African-American Students’ Perceptions of Engineering

The purpose of this study was to critically examine the perceptions that African-American high school students have towards engineering. A qualitative research design using criterion sampling and snowballing was used to select seven African-American students from urban high schools to participate in the research. Semi-structured interviews were used to collect data from participants attending urban high schools on the east and west coast. Using Critical Race Theory (CRT) as the theoretical framework, the study was able to produce “emergent themes” from collected data. Findings from this study will help researchers understand how African-American students may perceive the field of engineering.
Spin-polarized tunneling in hybrid metal-semiconductor magnetic tunnel junctions

We demonstrate efficient spin-polarized tunneling between a ferromagnetic metal and a ferromagnetic semiconductor with highly mismatched conductivities. This is indicated by a large tunneling magnetoresistance (up to 30%) at low temperatures in epitaxial magnetic tunnel junctions composed of a ferromagnetic metal (MnAs) and a ferromagnetic semiconductor $({\mathrm{Ga}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{x}\mathrm{As})$ separated by a nonmagnetic semiconductor (AlAs). Analysis of the current-voltage characteristics yields detailed information about the asymmetric tunnel barrier. The low temperature conductance-voltage characteristics show a zero bias anomaly and a $\sqrt{V}$ dependence of the conductance, suggesting a correlation gap in the density of states of ${\mathrm{Ga}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{x}\mathrm{As}.$ These experiments suggest that MnAs/AlAs heterostructures offer well characterized tunnel junctions for high efficiency spin injection into GaAs.
High transmission power increases the capacity of ad hoc wireless networks

In this paper, the effect of transmission power on the throughput capacity of finite ad hoc wireless networks, considering a scheduling-based medium access control (MAC) protocol such as time division multiple access (TDMA) and an interference model that is based on the received signal-to-interference-plus-noise ratio (SINR) levels, is analyzed and investigated. The authors prove that independent of nodal distribution and traffic pattern, the capacity of an ad hoc wireless network is maximized by properly increasing the nodal transmission power. Under the special case of their analysis that the maximum transmission power can be arbitrarily large, the authors prove that the fully connected topology (i.e., the topology under which every node can directly communicate with every other node in the network) is always an optimum topology, independent of nodal distribution and traffic pattern. The present result stands in sharp contrast with previous results that appeared in the literature for networks with random nodal distribution and traffic pattern, which suggest that the use of minimal common transmission power that maintains connectivity in the network maximizes the throughput capacity. A linear programming (LP) formulation for obtaining the exact solution to the optimization problem, which yields the throughput capacity of finite ad hoc wireless networks given a nodal transmit power vector, is also derived. The authors' LP-based performance evaluation results confirm the distinct capacity improvement that can be attained under their recommended approach, as well as identify the magnitude of capacity upgrade that can be realized for networks with random and uniform topologies and traffic patterns.
Intersection cuts from multiple rows: a disjunctive programming approach

We address the issue of generating cutting planes for mixed integer programs from multiple rows of the simplex tableau with the tools of disjunctive programming. A cut from \(q\) rows of the simplex tableau is an intersection cut from a \(q\)-dimensional parametric cross-polytope, which can also be viewed as a disjunctive cut from a \(2^q\)-term disjunction. We define the disjunctive hull of the \(q\)-row problem, describe its relation to the integer hull, and show how to generate its facets. For the case of binary basic variables, we derive cuts from the stronger disjunctions whose terms are equations. We give cut strengthening procedures using the integrality of the nonbasic variables for both the integer and the binary case. Finally, we discuss some computational experiments.
The galactic halo question - New size constraints from galactic gamma-ray data

Recent satellite observations of the distribution of galactic 100-MeV gamma rays and their interpretation are used as an independent test of the existence and extent of a cosmic-ray halo around the Galaxy. The cosmic-ray halo is defined, uniform and diffusion halo models are described, and the flat diffusion model is employed to investigate the effect of a diffusion halo on the galactic cosmic-ray distribution. Cosmic-ray source distributions that are perpendicularly uniform functions of galactocentric distance are adopted in the analysis. Possible longitudinal distributions of the gamma-ray line flux from neutral-pion decay are evaluated and compared with the fluxes observed by SAS-2 for goodness of fit. The results are shown to be consistent with a thick-disk or thin-halo model having a mean half-thickness of 1 to 3 kpc.
Comparative Analyses of Stated Behavioral Responses to Off-Hour Delivery Policies

The analyses reported in this paper show the benefits of using behavioral research to understand the stated behavioral responses of different economic agents (receivers and carriers) to off-hour delivery policies in two major business areas in New York City: Manhattan and Brooklyn. These policies include shipping discounts and a tax deduction for receivers and customer requests combined with either financial rewards or toll discounts for carriers. Given the relatively small amount of research conducted into stated and revealed behavioral responses, the results for Manhattan and Brooklyn provide insights into the operations of receiver and carrier companies in areas with similar characteristics.
The Contribution of Quasars to the Far-Infrared Background

Recent observational results obtained with the Submillimeter Common-User Bolometric Array, COBE, and the Infrared Space Observatory have greatly improved our knowledge of the infrared and submillimeter background radiation. These limits become constraining given the realization that most active galactic nuclei (AGNs) are heavily obscured and must reradiate strongly in the IR/submillimeter wavelengths. Here we predict the contribution of AGNs to the IR/submillimeter background, starting from measurements of the hard X-ray background. We show that an application of what we know of AGN spectral energy distributions and the IR background requires that a significant fraction of the 10-150 μm background comes from AGNs. This conclusion can be avoided only if obscured AGNs are intrinsically brighter in the X-rays (with respect to the optical-UV) than unobscured AGNs, which is contrary to "unified schemes" for AGNs, or if they have a dust-to-gas ratio much lower (≤0.1) than Galactic. We show that these results are rather robust and not strongly dependent on the details of the modeling.
Intramolecular Heck Reactions of Unactivated Alkyl Halides

A method has been developed for achieving palladium-catalyzed intramolecular Heck reactions of unactivated, β-hydrogen-containing alkyl bromides and chlorides. The data from a stereochemical investigation are consistent with carbon−carbon bond formation via an alkylpalladium, rather than a radical, intermediate.
Geochemical relationships of water in the Powder River basin, Wyoming and Montana

Geologic factors largely determine the composition and the amounts of dissolved solids that are transported by the Powder River and its tributaries. The chemical character of the water in the basin differs widely from one stream to another and is variable in each stream from headwaters to mouth. Mountainous areas underlain by igneous rocks of Precambrian age contribute small quantities of soluble materials to the river system; the concentration of mineral solids may be less than 50 ppm. Streams heading in upland country and draining a region that is largely underlain by Tertiary sandstones and shales transport salts in concentrations exceeding 2000 ppm. The composition of mineral substance in the river water can be correlated with occurrence in the area of such rocks as granite, limestone, gypsum, and shale.
Tidal Interaction of M32 and NGC 205 with M31: Surface Photometry and Numerical Simulations*

We investigate the interaction history of the M31 subgroup by comparing surface photometry of two of its satellites, M32 and NGC 205, with N-body simulations of satellite destruction. The recent discovery of a giant stream in the outer halo of M31, apparently pointed in the direction of M32 and NGC 205, makes such an investigation particularly relevant. The observational component of this study is based on 17 × 5° B- and I-band CCD mosaic images centered on M31 and covering both satellites. Standard ellipse-fitting techniques are used to model and remove M31 disk light and to perform surface photometry on the satellites to limiting brightness levels of (μB, μI) = (27, 25) mag arcsec-2, corresponding to isophotal semimajor axis lengths of r = 420'' (1.6 kpc) and r = 720'' (2.7 kpc). A hint of excess light in the outer parts of M32 noted in earlier studies is confirmed; in particular, clear evidence is seen for a sharp (upward) break in the surface brightness profile at r = 150'' relative to a r1/4 law that fits the inner region of M32. This break is accompanied by a steep increase in isophotal ellipticity , as well as position angle ' twisting. In addition to this excess, evidence is seen for an inner downward break in the surface brightness profile at r = 50''. The robustness of the M32 isophotal features is demonstrated through their (1) insensitivity to the details of background subtraction, (2) symmetry about M32's center, and (3) narrow range of B-I color that is consistent with the interior regions of M32 but not with M31 residual spiral arm/dust lane features. The study of NGC 205 reveals pronounced isophote twisting at r ~ 300'' that is coincident with a subtle downward break in the surface brightness profile, relative to an exponential law fitted to the inner region. The simulation component of this project is based on the analysis of single-component, spherical satellites that are being tidally disrupted through interactions with their parent galaxy. Generic features of the simulations include an excess in the surface brightness profile at large radii, a depletion zone at intermediate radii, and isophotal elongation and twists that are coincident with breaks in the brightness profile. The two satellites, M32 and NGC 205, display most of these features consistently across the B and I bands, which is strongly suggestive of tidal interaction and probable stripping by M31. We discuss what these observed features can tell us about the satellites' orbital parameters and histories. Specifically, M32 is found to be on a highly eccentric orbit and away from pericenter. Investigating M32's unusual combination of high surface brightness and low luminosity (the hallmark of compact ellipticals), we make empirical estimates of the galaxy's intrinsic properties and conclude that it is not likely to be the residual core of a tidally stripped normal elliptical galaxy, as has been suggested, but rather that its precursor was intrinsically compact.
Preequilibrium particle emission and the giant-dipole resonance in Sn nuclei

Light charged particles from ${}^{18}{\mathrm{O}+}^{100}\mathrm{Mo}$ reactions at 200 MeV bombarding energy have been measured in singles and in coincidence with high-energy \ensuremath{\gamma} rays $(g~10\mathrm{MeV})$ produced primarily in the decay of the giant-dipole resonance. Particle spectra are analyzed in terms of a moving source fit to decompose preequilibrium and evaporative components. Preequilibrium particle multiplicities and energies indicate a reduction in the compound nucleus excitation energy of approximately 20% and a loss of mass of approximately three mass units relative to complete fusion. The energy lost to preequilibrium emission is shown to affect significantly the strength, width, and centroid energy of the giant-dipole resonance deduced from fits to high-energy \ensuremath{\gamma}-ray emission spectra. Evaporation residue cross sections were measured for the same reaction from 100 to 217 MeV in order to determine the fusionlike event cross section.
3D models of lamprey corticoid receptor complexed with 11-deoxycortisol and deoxycorticosterone.

Abstract The serum of Atlantic sea lamprey, a basal vertebrate, contains two corticosteroids, 11-deoxycortisol and deoxycorticosterone. Only 11-deoxycortisol has high affinity [ K d ∼ 3 nM] for the corticoid receptor [CR] in lamprey gill cytosol. To investigate the binding of 11-deoxycortisol to the CR, we constructed 3D models of lamprey CR complexed with 11-deoxycortisol and deoxycorticosterone. These 3D models reveal that Leu-220 and Met-299 in lamprey CR have contacts with the 17α-hydroxyl on 11-deoxycortisol. Lamprey CR is the ancestor of the mineralocorticoid receptor [MR] and glucocorticoid receptor [GR]. Unlike human MR and human GR, the 3D model of lamprey CR finds a van der Waals contact between Cys-227 in helix 3 and Met-264 in helix 5. Mutant human MR and GR containing a van der Waals contact between helix 3 and helix 5 display enhanced responses to progesterone and glucocorticoids, respectively. We propose that this interaction was present in the CR and lost during the evolution of the MR and GR, leading to changes in their response to progesterone and corticosteroids, respectively.
Investigating a reading comprehension intervention for high school students with autism spectrum disorder: A pilot study

We adapted and piloted Collaborative Strategic Reading–High School, a reading comprehension intervention, with three high school students with autism spectrum disorder to investigate its effects on their reading comprehension. Using a nonconcurrent, multiple-baseline design, participants with autism spectrum disorder were paired with a neurologically typical (neurotypical) reading partner to learn and use reading strategies with informational text two to three times per week. Daily comprehension checks were collected and visually inspected for trends along with data on the number of challenging behaviors and social interactions displayed during intervention. Fidelity of implementation was also measured. Though exploratory, increases in comprehension and interactions were noted along with decreases in challenging behaviors. Implications for practice and research are discussed.
Practical preparation of Z-α-(n-acetylamino)-and Z -α -(N -benzoylamino )-α,β-unsaturated acids

Abstract An efficient two‐step synthetic procedure for the preparation of numerous variations of N‐protected α,β‐unsaturated α‐amino acids and their corresponding esters from N‐protected glycine and either aliphatic or aromatic aldehydes was developed. The reaction involved cyclization of the N‐protected glycine into oxazolone, condensation with the aldehyde, and ring opening with a base.
Couplings of vector-spinor representation for SO(10) model building

Higgs multiplet in the vector-spinor representations of SO(10), i.e., the 144+ multiplet can break the SO(10) gauge symmetry spontaneously in one step down to the Standard Model gauge group symmetry SU(3)C × SU(2)L × U(1)Y and a recent analysis has used such vector-spinors for building a new class of SO(10) grand unification models. Here we discuss the techniques for the computation of several classes of vector-spinor couplings using the recent result on the SO(2N) vertex expansion. The computations include the cubic couplings of the vector-spinors with SO(10) tensors, quartic self-couplings of the vector-spinors, and couplings of the vector-spinors with spinor representations of SO(10). The last set include couplings of vector-spinors with the 16-plets of quarks and lepton and with the 16 and of Higgs. These couplings provide a tool for further development of the SO(10) grand unification using vector-spinor representations. These include study of quark-lepton masses, analysis of dimension five operators including baryon and lepton number violating operators, and study of neutrino masses and mixings. Illustrative examples are given for their computation using a sample of vector-spinor couplings. The vector-spinor couplings arise in a wide class of models when one considers higher dimensional operators such as those that arise in the analysis of Planck scale physics and thus the techniques as well as the explicit couplings discussed here should find a wider application. .
Modelling Worker Residence Distribution in the Los Angeles Region

This paper examines the spatial pattern of worker residences with three different density functions: monocentric, polycentric, and dispersive. Analysis of the 1980 journey-to-work census data for the Los Angeles region reveals that the polycentric density function statistically explains the actual distribution better than the monocentric density function, but the dispersive density function fits best. These findings confirm a polycentric spatial pattern, and also imply that overall accessibility to employment opportunities is the primary determinant of residential location choices.
The Effects of Teenage Fertility on Young Adult Childbearing

Numerous studies of fertility behavior find that an early age at first birth increases the rate of subsequent childbearing. Typically, however, these studies do not account for the possibility of serial correlation in the unobserved determinants of fertility. Using 1979–1992 individual-level data from the National Longitudinal Survey of Youth, this paper employs the Method of Simulated Moments to estimate panel probit models of annual birth outcomes. The panel probit models account for several alternative sources of serial correlation. Estimation reveals that once serial correlation is taken into account, the subsequent fertility effects of early childbearing are either statistically eliminated or reversed.
Improved association in a classical density functional theory for water

We present a modification to our recently published statistical associating fluid theory-based classical density functional theory for water. We have recently developed and tested a functional for the averaged radial distribution function at contact of the hard-sphere fluid that is dramatically more accurate at interfaces than earlier approximations. We now incorporate this improved functional into the association term of our free energy functional for water, improving its description of hydrogen bonding. We examine the effect of this improvement by studying two hard solutes (a hard hydrophobic rod and a hard sphere) and a Lennard-Jones approximation of a krypton atom solute. The improved functional leads to a moderate change in the density profile and a large decrease in the number of hydrogen bonds broken in the vicinity of the hard solutes. We find an improvement of the partial radial distribution for a krypton atom in water when compared with experiment.
Regio- and enantioselective Pd-catalyzed allylic alkylation of ketones through allyl enol carbonates.

The Pd-catalyzed reorganization of enol allyl carbonates to allylated ketones occurs asymmetrically in the presence of chiral ligands previously developed in this group. With 2-methylcyclohexanone,...
Prediction of semiconductor band edge positions in aqueous environments from first principles

The ability to predict a semiconductor's band edge positions in solution is important for the design of water-splitting photocatalyst materials. In this paper, we introduce a first-principles method to compute the conduction-band minima of semiconductors relative to the water ${\mathrm{H}}_{2}$O/H${}_{2}$ level using density functional theory with semilocal functionals and classical molecular dynamics. We test the method on six well known photocatalyst materials: TiO${}_{2}$, WO${}_{3}$, CdS, ZnSe, GaAs, and GaP. The predicted band edge positions are within 0.34 eV of the experimental data, with a mean absolute error of 0.19 eV.
Off-resonant coupling between a single quantum dot and a nanobeam photonic crystal cavity

We demonstrate off-resonant coupling between a single quantum dot and a nanobeam photonic crystal cavity, under resonant excitation of the dot or the cavity. We confirm that this is an incoherent phonon-mediated process.
New ternary nitride in the Ti-Al-N system

The ternary compound Ti3Al1−xN2 was found to be stable between} 1523 and 1673 K and tended to be deficient in aluminum where 0.0 × 0.3. X-ray diffraction indicated that the ternary compound possessed a hexagonal structure with unit-cell dimensions of a0= 2.990 and c0= 23.3854. The existence of the compound “Ti3Al2N2” that had been reported previously could not be confirmed for any experimental conditions at 1 atm pressure.
On‐board closed‐loop congestion control for satellite‐based packet‐switching networks

NASA Lewis Research Center is currently investigating a satellite architecture that incorporates an on-board packet-switching capability. Because of the statistical nature of packet switching, arrival traffic may fluctuate, and thus it is necessary to integrate the congestion control mechanism as part of the on-board processing unit. This study focuses on the closed-loop reactive control. We investigate the impact of the long propagation delay on the performance, and propose a scheme to overcome the problem. The scheme uses a global feedback signal to regulate the packet arrival rate of the ground stations. In this scheme, the satellite continuously broadcasts the status of its output buffer and the ground stations respond by selectively discarding packets or by tagging the excessive packets as low-priority. The two methods are evaluated by theoretical queueing analysis and simulation. The former is used to analyse the simplified model and to determine the basic trends and bounds, and the latter is used to assess the performance of a more realistic system and to evaluate the effectiveness of more sophisticated control schemes. The results show that the long propagation delay makes the closed-loop congestion control less responsive. The broadcast information can only be used to extract statistical information. The discarding method needs carefully-chosen status information and a reduction function, and normally requires a significant amount of ground discarding to reduce the on-board packet loss probability. The tagging method is more effective since it tolerates more uncertainties and allows a larger margin of error in status information. It can protect the high-priority packets from excessive loss and fully use the down-link bandwidth at the same time.
Enantioselective α-Amination of 1,3-Dicarbonyl Compounds Using Squaramide Derivatives as Hydrogen Bonding Catalysts

Catalytic enantioselective α-hydrazination of 1,3-dicarbonyl compounds with azodicarboxylates was investigated in the presence of our newly developed hydrogen bonding catalyst, squaramide 3j. High yields and high enantioselectivities were achieved with low catalyst loading under mild conditions.
Introduction to M(atrix) theory and noncommutative geometry

Abstract Noncommutative geometry is based on an idea that an associative algebra can be regarded as “an algebra of functions on a noncommutative space”. The major contribution to noncommutative geometry was made by A. Connes, who, in particular, analyzed Yang–Mills theories on noncommutative spaces, using important notions that were introduced in his papers (connection, Chern character, etc). It was found recently that Yang–Mills theories on noncommutative spaces appear naturally in string/M-theory; the notions and results of noncommutative geometry were applied very successfully to the problems of physics. In this paper we give a mostly self-contained review of some aspects of M(atrix) theory, of Connes’ noncommutative geometry and of applications of noncommutative geometry to M(atrix) theory. The topics include introduction to BFSS and IKKT matrix models, compactifications on noncommutative tori, a review of basic notions of noncommutative geometry with a detailed discussion of noncommutative tori, Morita equivalence and SO (d,d| Z ) -duality, an elementary discussion of noncommutative orbifolds, noncommutative solitons and instantons. The review is primarily intended for physicists who would like to learn some basic techniques of noncommutative geometry and how they can be applied in string theory and to mathematicians who would like to learn about some new problems arising in theoretical physics. The second part of the review (Sections 10–12) devoted to solitons and instantons on noncommutative Euclidean space is almost independent of the first part.
Alternative Solution of Strong CP

Abstract In this talk I begin with some general discussion of the history of CP violation, then move on to aspects of a spontaneous CP violation model including the production of new particles at LHC, implications for B decay, generalized Cabibbo mixing and a reevaluation of kaon CP violation. Finally there is a summary.
Hadron masses from the valence approximation to lattice QCD

Abstract We evaluate pseudoscalar, vector, spin 1 2 and spin 3 2 baryon masses predicted by lattice QCD with Wilson quarks in the valence (quenched) approximation for a range of different values of lattice spacing, lattice volume and quark mass. Extrapolating these results to physical quark mass, then to zero lattice spacing and infinite volume we obtain values for eight mass ratios. We also determine the zero lattice spacing, infinite volume limit of an alternate set of five quantities found without extrapolation in quark mass. Both sets of predictions differ from the corresponding observed values by amounts consistent with the predicted quantities' statistical uncertainties.
Price Regulation in Secondary Insurance Markets

Secondary life insurance markets are growing rapidly. From nearly no transactions in 1980, a wide variety of similar products in this market has developed, including viatical settlements, accelerated death benefits, and life settlements and as the population ages, these markets will become increasingly popular. Eight state governments, in a bid to guarantee sellers a “fair” price, have passed regulations setting a price floor on secondary life insurance market transactions, and more are considering doing the same. Using data from a unique random sample of HIV+ patients, we estimate welfare losses from transactions prevented by binding price floors in the viatical settlements market (an important segment of the secondary life insurance market). We find that price floors bind on HIV patients with greater than 4 years of life expectancy. Furthermore, HIV patients from states with price floors are significantly less likely to viaticate than similarly healthy HIV patients from other states. If price floors were adopted nationwide, they would rule out transactions worth $119 million per year. We find that the magnitude of welfare loss from these blocked transactions would be highest for consumers who are relatively poor, have weak bequest motives, and have a high rate of time preference.
Charge Exchange Spectra of Hydrogenic and He-like Iron

We present H-like Fe XXVI and He-like Fe XXV charge-exchange spectra resulting from collisions of highly charged iron with N2 gas at an energy of ~10 eV amu-1 in an electron beam ion trap. Although individual high-n emission lines are not resolved in our measurements, we observe that the most likely level for Fe+25 → Fe+24 electron capture is nmax ~ 9, in line with expectations, while the most likely value for Fe+26 → Fe+25 charge exchange is significantly higher. In the Fe XXV spectrum, the Kα emission feature dominates, whether produced via charge exchange or collisional excitation. The Kα centroid is lower in energy for the former case than for the latter (6666 vs. 6685 eV, respectively), as expected because of the strong enhancement of emission from the forbidden and intercombination lines, relative to the resonance line, in charge-exchange spectra. In contrast, the Fe XXVI high-n Lyman lines have a summed intensity greater than that of Lyα and are substantially stronger than predicted from theoretical calculations of charge exchange with atomic H. We conclude that the angular momentum distribution resulting from electron capture using a multielectron target gas is significantly different from that obtained with H, resulting in the observed high-n enhancement. A discussion is presented of the relevance of our results to studies of diffuse Fe emission in the Galactic center and Galactic ridge, particularly with Astro-E2/Suzaku.
A Statistical Treatment of the Gamma-Ray Burst ``No Host Galaxy'' Problem.II. Energies of Standard Candle Bursts

With the discovery that the afterglows after some bursts are coincident with faint galaxies, the search for host galaxies is no longer a test of whether bursts are at cosmological distances, but rather a test of particular cosmological models. The methodology we developed to investigate the original "no host galaxy" problem is equally valid for testing different cosmological models and is applicable to the galaxies coincident with optical transients. We apply this methodology to a family of models where we vary the total energy of standard candle bursts. We find that total isotropic energies of E<2×1052 ergs are ruled out, while E~1053 ergs is favored.
State Complexes for Metamorphic Robots

A metamorphic robotic system is an aggregate of homogeneous robot units which can individually and selectively locomote in such a way as to change the global shape of the system. We introduce a mathematical framework for defining and analyzing general metamorphic robots. With this formal structure, combined with ideas from geometric group theory, we define a new type of configuration space for metamorphic robots—the state complex—which is especially adapted to parallelization. We present an algorithm for optimizing an input reconfiguration sequence with respect to elapsed time. A universal geometric property of state complexes—non-positive curvature—is the key to proving convergence to the globally timeoptimal solution obtainable from the initial path.
A Guidance and Control Algorithm for Scent Tracking Micro-Robotic Vehicle Swarms

Cooperative micro-robotic scent tracking vehicles are designed to collectively “sniff out” locations of high scent concentrations in unknown, geometrically complex environments. These vehicles are programed with guidance and control algorithms that allow inter cooperation among vehicles. In this paper, a cooperative guidance and control algorithm for scent tracking micro-robotic vehicles is presented. This algorithm is comprised of a sensory compensation sub-algorithm using point source cancellation, a guidance sub-algorithm using gradient descent tracking, and a control sub-algorithm using proportional feedback. The concepts of social rank and point source cancellation are new concepts introduced within. Simulation results for cooperative vehicles swarms are given. Limitations are discussed.
Tricyclic ureas: A new class of HIV-1 protease inhibitors

A new class of tricyclic ureas containing a conformationally constrained proline was designed with the aid of molecular modeling. Efficient stereoselective intermolecular pinacol coupling represented the highlight of the synthesis. These rigid cyclic ureas are active towards HIV-1 protease, with 9 being the most potent compound (Ki = 9 nM) despite interacting with only three side chain binding pockets of HIV protease.