cssi/SciSciGPT-SciSciNet huggingface dataset:
Can Cost-Benefit Analysis Guide Education Policy in Developing Countries?

Cost-benefit analysis in education is an important tool in the economists' arsenal. However, it is essential that research, especially on the social benefits of education, make further progress to make cost-benefit more analysis. There is a need for more research on the effects of policy interventions on outcomes beyond access to a year in school and what they earn as a result, such as on what children actually learn. Such research should focus on ensuring that the interventions are attributable to outcomes. Nevertheless, it is worthwhile to go through the discipline of noting the benefits and costs, even if social rates of return cannot be calculated robustly.
On curves with nonnegative torsion

We provide new results and new proofs of results about the torsion of curves in \({\mathbb{R}^3}\). Let \({\gamma}\) be a smooth curve in \({\mathbb{R}^3}\) that is the graph over a simple closed curve in \({\mathbb{R}^2}\) with positive curvature. We give a new proof that if \({\gamma}\) has nonnegative (or nonpositive) torsion, then \({\gamma}\) has zero torsion and hence lies in a plane. Additionally, we prove the new result that a simple closed plane curve, without any assumption on its curvature, cannot be perturbed to a closed space curve of constant nonzero torsion. We also prove similar statements for curves in Lorentzian \({\mathbb{R}^{2,1}}\) which are related to important open questions about time flat surfaces in spacetimes and mass in general relativity.
Measures of distortion in possibilistic approximations of consistent random sets and intervals

The available of probability or possibility measures for random set (Dempster-Shafer evidence theoretical) structures are highly desirable. Probabilistic conditions involve disjointness or specificity, while possibilistic conditions involve consonance of the underlying focal elements. Consistency results in possibilistic distributions, but not measures, and a unique approximation is available. Especially in random interval measurement situations, this condition is common. In this paper we develop some of the mathematical ideas necessary to develop a measure of the distortion introduced by this consonant approximation of a consistent random set.
Buyer and Seller Concentration in Global Commodity Markets

In recent years there has been an increased incidence of export restrictions applied by developing countries to commodities and raw materials. Commodity markets may be characterized by concentration on the buyer side, with a small number of transnational intermediary firms purchasing from supplying countries and distributing to the market, and recent work has suggested that export taxes may be an optimal policy to recapture monopsony rent. However, in many commodity markets there are also a limited number of large supplying countries. This paper considers a situation where an oligopsonistic intermediary industry purchases from a small number of supplying countries, the governments of which act strategically in their policy choices both with respect to the intermediaries and any competing suppliers. In the resulting two-stage game, the paper shows that an export subsidy, rather than an export tax, may arise as the optimal intervention.
Constraint-based Interoperability of Spatiotemporal Databases*

We propose constraint databases as an intermediate level facilitating the interoperability of spatiotemporal data models. Constraint query languages are used to express translations between different data models. We illustrate our approach in the context of a number of temporal, spatial, and spatiotemporal data models.
The Weibull distribution and Benford's law

Benford’s law states that many data sets have a bias towards lower leading digits, with a first digit of 1 about 30.1% of the time and a 9 only 4.6%. There are numerous applications, ranging from designing efficient computers to detecting tax, voter and image fraud. An important, open problem is to determine which common probability distributions are close to Benford’s law. We show that the Weibull distribution, for many values of its parameters, is close to Benford’s law, and derive an explicit formula measuring the deviations. As the Weibull distribution arises in many problems, especially survival analysis, our results provide additional arguments for the prevalence of Benford behavior.
Structure and Motion Estimation from Dynamic Silhouettes under Perspective Projection

We address the problem of estimating the structure and motion of a smooth curved object from its silhouettes observed over time by a trinocular stereo rig under perspective projection. We first construct a model for the local structure along the silhouette for each frame in the temporal sequence. The local models are then integrated into a global surface description by estimating the motion between successive time instants. The algorithm tracks certain surface features (parabolic points) and image features (silhouette inflections and frontier points) which are used to bootstrap the motion estimation process. The entire silhouettes along with the reconstructed local structure are then used to refine the initial motion estimate. We have implemented the proposed approach and report results on real images.
Reflexiones sobre distintos modelos de intercambio simbólico entre la cultura afrocaribeña y la cultura hispánica en el caribe costarricense. Respuestas de un calypsonian de Cahuita

En este trabajo se discute el potencial contestatario del calypso limonense, asi como los modos en los cuales el calypso es un medio para afirmar la identidad cultural de los afrodescendientes frente a la cultura blanca y mestiza de Costa Rica. En particular, se analizan las representaciones de los afrodescendientes en los calypsos de Walter Ferguson. Se propone entender el calypso no solamente como un genero musical, sino tambien como una forma de literatura oral del caribe costarricense y en ese sentido se lleva a cabo una lectura de dichos calypsos en el contexto de otros textos literarios de y sobre afrodescendientes en el caribe costarricense. La cultura del calypso – tal como se la describe en este articulo – demuestra la existencia de una literatura oral y una musica afrocostarricense en dialogo critico con la cultura del mainstream costarricense.
On the origin of multi-component bulk metallic glasses: Atomic size mismatches and de-mixing

The likelihood that an undercooled liquid vitrifies or crystallizes depends on the cooling rate R. The critical cooling rate R(c), below which the liquid crystallizes upon cooling, characterizes the glass-forming ability (GFA) of the system. While pure metals are typically poor glass formers with R(c)>10(12)K/s, specific multi-component alloys can form bulk metallic glasses (BMGs) even at cooling rates below R∼1 K/s. Conventional wisdom asserts that metal alloys with three or more components are better glass formers (with smaller R(c)) than binary alloys. However, there is currently no theoretical framework that provides quantitative predictions for R(c) for multi-component alloys. In this manuscript, we perform simulations of ternary hard-sphere systems, which have been shown to be accurate models for the glass-forming ability of BMGs, to understand the roles of geometric frustration and demixing in determining R(c). Specifically, we compress ternary hard sphere mixtures into jammed packings and measure the critical compression rate, below which the system crystallizes, as a function of the diameter ratios σ(B)/σ(A) and σ(C)/σ(A) and number fractions x(A), x(B), and x(C). We find two distinct regimes for the GFA in parameter space for ternary hard spheres. When the diameter ratios are close to 1, such that the largest (A) and smallest (C) species are well-mixed, the GFA of ternary systems is no better than that of the optimal binary glass former. However, when σ(C)/σ(A) ≲ 0.8 is below the demixing threshold for binary systems, adding a third component B with σ(C) < σ(B) < σ(A) increases the GFA of the system by preventing demixing of A and C. Analysis of the available data from experimental studies indicates that most ternary BMGs are below the binary demixing threshold with σ(C)/σ(A) < 0.8.
Extreme eigenvalues of sparse, heavy tailed random matrices

Abstract We study the statistics of the largest eigenvalues of p × p sample covariance matrices Σ p , n = M p , n M p , n ∗ when the entries of the p × n matrix M p , n are sparse and have a distribution with tail t − α , α > 0 . On average the number of nonzero entries of M p , n is of order n μ + 1 , 0 ≤ μ ≤ 1 . We prove that in the large n limit, the largest eigenvalues are Poissonian if α 2 ( 1 + μ − 1 ) and converge to a constant in the case α > 2 ( 1 + μ − 1 ) . We also extend the results of Benaych-Georges and Peche (2014) in the Hermitian case, removing restrictions on the number of nonzero entries of the matrix.
Quantitative photochemistry of organometallic complexes: insight to their photophysical and photoreactivity mechanisms

Abstract This review describes a recently developed photokinetic method for studying the quantitative photochemistry of systems where there are overlapping absorbances and inner filter effects at the excitation wavelength. The procedure has been applied to investigate the wavelength-dependent photochemistry of several organometallic complexes and, for each case, the results illustrate that the lowest-lying electronically excited states have different intrinsic reactivities. In each of the systems studied, the determined quantitative data has led to valuable new insight into their photophysical and photochemical mechanisms.
Optimal sliding-mode control of a flexible spacecraft under stochastic disturbances

A new optimal sliding mode (OSM) controller is developed for a linear stochastic system and applied to the Middeck Active Control Experiment (MACE) which represents the control structure interaction problem for a precision spacecraft. The OSM controller minimizes the expected value of a quadratic objective function consisting of only states with the constraints that estimated states always remain on the intersection of sliding hyperplanes This controller is designed for two subsets of MACE problems: a single input, single output gimbal inertial pointing problem and a three input, three output torque wheel attitude control problem. Using numerical simulations, performance of the OSM controller is compared to that of the classical LQG controller. The OSM controllers are digitally implemented on the Development Model of MACE. The experimental results are shown to be in good agreement with theoretical results.
General Eulerian Numbers and Eulerian Polynomials

We will generalize the definitions of Eulerian numbers and Eulerian polynomials to general arithmetic progressions. Under the new definitions, we have been successful in extending several well-known properties of traditional Eulerian numbers and polynomials to the general Eulerian polynomials and numbers.
Constructive quantum Shannon decomposition from Cartan involutions

The work presented here extends upon the best known universal quantum circuit, the quantum Shannon decomposition proposed by Shende et al (2006 IEEE Trans. Comput.-Aided Des. Integr. Circuits Syst. 25 1000). We obtain the basis of the circuit's design in a pair of Cartan decompositions. This insight gives a simple constructive factoring algorithm in terms of the Cartan involutions corresponding to these decompositions.
Oxidative rearrangement of alkynes to carboxylic acid esters by [Hydroxy(tosyloxy)iodo]benzene in methanol

Abstract A direct synthesis of methyl aryl alkanoate via oxidative rearrangement of alkynes using [hydroxy(tosyloxy)iodo]benzene in methanol is described.
ZINC OXIDE NANOPARTICLES FOR ULTRAVIOLET PHOTODETECTION

Zinc Oxide (ZnO) nanoparticles were created by a top-down wet-chemistry synthesis process (ZnO-A) and then coated with polyvinyl-alcohol (PVA) (ZnO-U). In ZnO-U, strong UV emission was apparent while the parasitic green emission, which normally appears in ZnO suspensions, was suppressed. A standard lift-off process via e-beam lithography was used to fabricate a detector by evaporating Aluminum (Al) as ohmic electrodes on the ZnO nanoparticle film. Photoconductivity experiments showed that linear current-voltage response were achieved and the ZnO-U nanoparticles based detector had a ratio of UV photo-generated current more than 5 times better than that of the ZnO-A based detector. In addition, non-linear current-voltage responses were observed when interdigitated finger Gold (Au) contacts were deposited on ZnO-U. The UV generated current to dark current ratios were between 4 and 7 orders of magnitude, showing better performance than the photodetector with Al contacts. ZnO-U were also deposited on Gallium Nitride (GaN) and Aluminum Gallium Nitride (AlGaN) substrates to create spectrally selective photodetectors. The responsivity of detector based on AlGaN is twice that of commercial UV enhanced Silicon photodiodes. These results confirmed that ZnO nanoparticles coating with PVA is a good material for small-signal, visible blind, and wavelength selective UV detection.
Synthesis of trans-syn-trans fused bis-pyrans via endo-selective cyclizations of cyclic sulfates

Abstract Acid-catalyzed cyclization of hydroxy-cyclic sulfates occurs with endo -regioselectivity affording bispyran products from substrates in which the nucleophilic hydroxyl and electrophilic cyclic sulfate groups are 1,2- trans -substituted on a cyclic pyran template. This methodology is demonstrated in an enantioselective synthesis of the trans-syn-trans fused AB cyclic ether rings of the brevetoxin natural products.
Microwave-expedited olefin epoxidation over hydrotalcites using hydrogen peroxide and acetonitrile

An efficient microwave-assisted epoxidation of olefins is described over hydrotalcite catalysts in the presence of hydrogen peroxide and acetonitrile. This general and selective protocol is extremely fast and is applicable to a wide variety of substrates.
Embedding meshes on the star graph

Abstract We develop algorithms for mapping n -dimensional meshes on a star graph of degree n with expansion 1 and dilation 3. We show that an n -degree star graph can efficiently simulate an n -dimensional mesh.
Simulating lattice QCD at finite density

A new method of simulating systems with a complex action which was recently introduced is applied to lattice QCD at finite density. At infinite gauge coupling we obtain a phase diagram which, in nice agreement with mean-field theory, gives a critical value of the chemical potential unrelated to the baryon mass. At the same time we demonstrate explicitly the failure of the quenched approximation.
Mechanism of the hydroxyiodination of 2-butenoic acid

Aqueous iodination of trans-2-butenoic acid proceeds via hydrolysis of I2 to form HOI and I−, then rapid addition of HOI across the double bond to form the iodohydrin product. In the presence of iodate to keep iodide concentration low, the reaction proceeds at a conveniently measurable rate. The rate for the addition reaction is −d[C4H6O2]/dt = 5900 [H+][C4H6O2][HOI]M/s at 25.0°C when [IO] = 0.025M and ionic strength = 0.3. The overall rate law in the presence of iodate is where [H+] and [IO] are total concentrations used to prepare the solution.
Nickel-Catalyzed Cycloadditive Couplings of Enynes and Isocyanates

A mild and general route for preparing dienamides is described. Nickel imidazolylidene complexes were used to mediate cycloadditive coupling between enynes and isocyanates. Dienamides were prepared in excellent yields and with good E:Z selectivity. These dienamides can be further manipulated through oxidative cyclization methods. When a terminal enyne is employed, cyclization affords a lactam rather than a dienamide.
Rhodium-Catalyzed Oxidative Cycloaddition of Benzamides and Alkynes via C−H/N−H Activation

The oxidative cycloaddition of benzamides and alkynes has been developed. The reaction utilizes Rh(III) catalysts in the presence of Cu(II) oxidants, and is proposed to proceed by N−H metalation of the amide followed by ortho C−H activation. The resultant rhodacycle undergoes alkyne insertion to form isoquinolones in good yield. The reaction is tolerant of extensive substitution on the amide, alkyne, and arene, including halides, silyl ethers, and unprotected aldehydes as substituents. Unsymmetrical alkynes proceed with excellent regioselectivity, and heteroaryl carboxamides are tolerated leading to intriguing scaffolds for medicinal chemistry. A series of competition experiments shed further light on the mechanism of the transformation and reasons for selectivity.
A multidisciplinary design optimization approach for high temperature aircraft engine components

Rapid turn-around time for investigating new design concepts is a primary force driving design productivity initiatives across the industry. An integration framework focusing on the collaborative nature of rapid design automation at the preliminary and detailed design stage would ensure higher quality designs from the beginning of the product design cycle. As a result, producing reliable, robust optimum designs from the preliminary design phase would enable companies to reduce the overal design cycle time.
IRAS 18317–0757: A Cluster of Embedded Massive Stars and Protostars

We present high-resolution, multiwavelength-continuum, and molecular-line images of the massive star forming region IRAS 18317-0757. The global infrared through millimeter spectral energy distribution can be approximated by a two-temperature model (25 and 63 K) with a total luminosity of approximately log(L/L☉) = 5.2. Previous submillimeter imaging resolved this region into a cluster of five dust cores, one of which is associated with the ultracompact H II region G23.955+0.150, and another with a water maser. In our new 2.7 mm continuum image obtained with BIMA, only the UCH II region is detected, with total flux and morphology in good agreement with the free-free emission in the VLA centimeter-wave maps. For the other four objects, the nondetections at 2.7 mm and in the MSX mid-infrared bands are consistent with cool dust emission with a temperature of 13-40 K and a luminosity of 1000-40,000 L☉. By combining single-dish and interferometric data, we have identified over two dozen virialized C18O cores in this region that contain ≈40% of the total molecular gas mass present. While the overall extent of the C18O and dust emission is similar, the emission peaks do not correlate well in detail. At least 11 of the 123 infrared stars identified by 2MASS in this region are likely to be associated with the star-forming cluster. Two of these objects (both associated with the UCH II region) were previously identified as O stars via infrared spectroscopy. Most of the rest of the reddened stars have no obvious correlation with the C18O cores or the dust continuum sources. In summary, our observations indicate that considerable fragmentation of the molecular cloud has taken place during the time required for the UCH II region to form and for the O stars to become detectable at infrared wavelengths. Additional star formation appears to be ongoing on the periphery of the central region, where up to four B-type (proto)stars have formed among a substantial number of C18O cores.
Aminoalkyl)indole Isothiocyanates as Potential Electrophilic Affinity Ligands for the Brain Cannabinoid Receptor

A series of (aminoalkyl)indole compounds, naphthalene analogs of pravadoline (1), has been shown to exhibit cannabinoid agonist activities such as antinociception in animals, inhibition of adenylate cyclase in brain membranes, and binding to the cannabinoid receptor. These pravadoline analogs were selected for the preparation of potential electrophilic affinity ligands based on the synthesis of isothiocyanate derivatives. One isothiocyanatonaphthalene derivative (8) displaced [3H]CP-55940 binding to a rat brain P2 membrane preparation with an IC50 of 690 nM, which was 10-fold less potent than the parent molecule (IC50 = 73 nM). Isothiocyanate substitution at various positions on the naphthalene moiety of the desmethyl analog 10 gave compounds that displaced [3H]CP-55940 with IC50 values between 400 and 1000 nM, compared with 46 nM for the parent compound 10. However, 6-isothiocyanato substitution on the indole ring of the desmethyl analog provided isothiocyanate 12 that displaced [3H]CP-55940 binding with an IC50 and 160 nM. After pretreatment of brain membranes with this high-affinity isothiocyanato ligand followed by washing out the ligand, the membranes were depleted of 90% of the cannabinoid receptor binding capacity. Loss of receptor binding capacity was half-maximal at 300 nM of the derivative under standard assay conditions. As a control, pretreatment with the parent compound at concentrations that were 20 times the Kd failed to alter subsequent binding activity. This study demonstrates that an isothiocyanato (aminoalkyl)-indole (12) can behave as an affinity ligand which binds irreversibly to the cannabinoid receptor in brain and which precludes subsequent binding of the cannabinoid ligand [3H]CP-55940.
Baryogenesis, electric dipole moments and dark matter in the MSSM

We study the implications for electroweak baryogenesis (EWB) within the minimal supersymmetric Standard Model (MSSM) of present and future searches for the permanent electric dipole moment (EDM) of the electron, for neutralino dark matter, and for supersymmetric particles at high energy colliders. We show that there exist regions of the MSSM parameter space that are consistent with both present two-loop EDM limits and the relic density and that allow for successful EWB through resonant chargino and neutralino processes at the electroweak phase transition. We also show that under certain conditions the lightest neutralino may be simultaneously responsible for both the baryon asymmetry and the dark matter. We give present constraints on chargino/neutralino-induced EWB implied by the flux of energetic neutrinos from the Sun, the prospective constraints from future neutrino telescopes and ton-sized direct detection experiments, and the possible signatures at the Large Hadron Collider and International Linear Collider.
Sigma Models And The ADHM Construction Of Instantons

Abstract This paper is devoted to the construction of a family of linear sigma models with (0,4) supersymmetry which should flow in the infrared to the stringy version of Yang-Mills instantons on R 4. The family depends on the full set of expected parameters and is obtained by using the data that appear in the ADHM construction of instantons.
Uncertainty Analysis of Composite Structures

A two-phase approach and a computational procedure are presented for predicting the variability in the nonlinear response of composite structures associated with variations in the geometric and material parameters of the structure. In the first phase, hierarchical sensitivity analysis is used to identify the major parameters, which have the most effect on the response quantities of interest. In the second phase, the major parameters are taken to be fuzzy parameters, and a fuzzy set analysis is used to determine the range of variation of the response, associated with preselected variations in the major parameters. The effectiveness of the procedure is demonstrated by means of a numerical example of a cylindrical panel with four T-shaped stiffeners and a circular cutout.
Catalytic asymmetric synthesis of peptides on polymer support

Abstract A novel approach to the synthesis of peptides through the catalytic asymmetric hydrogenation of dehydrotripeptides linked to the Wang resin, using rhodium complexes with chiral diphosphine ligands as the catalysts, is described.
Statistics of the pinning field in a soft metallic ferromagnet

Barkhausen noise, measured at four different sweep rates, is used to reconstruct and study the effective pinning field present in an amorphous metallic ferromagnet. This reconstruction technique gives pinning field spatial spectra similar to those measured previously. However, the pinning field is not reproducible from sweep to sweep and has statistical properties which depend systematically on the sweep rate, confirming that it is a collective effect of the dynamics of flexible domain walls. The statistics were non-Gaussian, requiring some modification of theories of effective pinning potentials.
Turbojet and Turbofan Engine Performance Increases Through Turbine Burners

In a conventional turbojet and turbofan engine, fuel is burned in the main combustor before the heated highpressure gas expands through the turbine. A turbine-burner concept was proposed in a previous paper in which combustion is continued inside the turbine to increase the efe ciency and speciec thrust of the turbojet engine. This concept is extended to include not only continuous burning in the turbine but also “discrete” interstage turbine burners as an intermediate option. A thermodynamic cycle analysis is performed to compare the relative performances of the conventional engineand theturbine-burner engine with differentcombustion options for both turbojet and turbofan conegurations. Turbine-burner engines are shown to provide signie cantly higher specie c thrust with no or only small increases in thrust specie c fuel consumption compared to conventional engines. Turbine-burner engines also widen the operational range of e ight Mach number and compressor pressure ratio. The performance gain of turbine-burner engines over conventional engines increases with compressor pressure ratio, fan bypass ratio, and eight Mach number.
Synthesis and solid state structure of some 2,6-diphenylphenoxide derivatives of rhodium(I) and iridium(I)

Abstract Treatment of the carbonyl dimer Rh2Cl2(CO)4 with 2 equivalents of LiOAr-2,6Ph2 (OAr-2,6Ph2 = 2,6-diphenylphenoxide) produces the aryloxide bridged dimer [(CO)2Rh(μ-OAr-2,6Ph2)2Rh(CO)2] (1) in excellent yield. Compound 1 shows two, equal intensity carbonyl stretching frequencies at 2090 and 2006 cm−1 in the IR spectrum (Nujol mull) consistent with a solid state structure consisting of two edge shared square planes. A single crystal X-ray diffraction analysis of 1 confirmed this formulation showing no evidence for Π-bonding by the side chain aryl groups to the 16-electron metal centre. Treatment of the dimer Ir2Cl2(COD)2 (COD = 1,5-cyclooctadiene) with LiOAr-2,6Ph2 yielded a mixture of products. Eventually sparingly soluble crystals of a salt [(COD)Ir(η5-HOAr-2,6Ph2)]+[(COD)Ir(OAr-2,6Ph2)2]− (2) were obtained in very minor yield. The presence of a 2,6-diphenylphenol ligand η5-bound through the central phenoxy ring to the iridium metal centre was confirmed by a single crystal X-ray diffraction analysis of 2. The distances IrC to the COD ligand in the cation in 2, 2.10(2)–2.16(2) A, are slightly shorter than the distances of 2.25(2)–2.35(2) A to the five carbon atoms of the central phenoxy ring. The ipso carbon attached to the hydroxyl group is non-bound. The anion in 2 contains two terminal aryloxide ligands bound approximately trans to the two iridium-olefinic bonds of the COD group yielding a structure best described as square planar. Crystal data at 20°C for Rh2O6C40H26 (1): a = 10.750(2), b = 28.307(5), c = 11.311(2) A, β = 96.21(1)°, Z = 4, dcalc = 1.569 g cm−3 in space group P21/n; for Ir2Cl6O3C72H58 (2) 2CHCl3: a = 13.428(2), b = 22.838(3), c = 20.937(2) A, β = 92.775(9)°, Z = 4, dcalc = 1.624 g cm−3 in space group P21/n.
Deuteration of pyridine derivatives : a very mild procedure

Abstract Ruthenium on carbon selectively catalyzes the hydrogen-deuterium exchange of pyridine derivatives at the ortho position. The reaction takes place at ambient temperature under mild conditions.
Income Uncertainty and Optimal Redistribution

1. Introduction Redistribution policy under a utilitarian criterion aims to transfer dollars from one group in the population to another if the (weighted) utility gain to the recipients exceeds the utility cost to the donors. Under diminishing marginal utility of income, part of any exogenous change in one group's income should be shared with the other group. For example, if taxpaying workers suffer a negative shock to their mean earnings, then part of this utility shock should be spread to nonworkers in the form of lower transfer payments, and vice versa for the case of a positive shock. This article demonstrates the counterintuitive result that, under reasonable preference representations, a policymaker may respond optimally to a negative utility shock by redistributing income away from the harmed group, thus exacerbating the group's utility loss. In particular, under risk aversion, a mean-preserving increase in the variance of income typically has an effect on well being analogous to a decrease in mean income.1 It may nevertheless be welfare enhancing to transfer income away from those suffering an increase in income uncertainty even though this policy compounds their welfare loss. The main ideas can be demonstrated in a simple framework. For illustration, the analysis will focus on redistribution from taxpaying workers to nonworkers. The central result is that a meanpreserving increase in earnings uncertainty among taxpayers can increase optimal transfer amounts to nonworkers (increasing optimal income replacement rates) even though the redistribution exacerbates the taxpayers' utility loss from the increase in uncertainty. 2. Model [Footnote]1 Many factors in the economy affect earnings uncertainty even conditional on being employed, such as the form of compensation (e. …
Selective oxidations of activated alcohols in water at room temperature

Allylic and benzylic alcohols can be selectively oxidized to their corresponding aldehydes or ketones in water containing nanoreactors composed of the designer surfactant TPGS-750-M. The oxidation relies on catalytic amounts of CuBr, bpy, and TEMPO, with N-methyl-imidazole; air is the stoichiometric oxidant.
Ring Formylation of Bromobenzoate Esters by Direct Metalation

Abstract A study on the synthesis of a benzaldehyde containing an ester function directly from tert-butyl 4-lithiobenzate was described. t-Butyl 4-bromobenzoate reacted with butyllithium at -78°C in THF, followed by immediate addition of DMF to give the desired benzaldehyde in moderate yield. The scope of this reaction was examined.
Parity of the partition function

Abstract Although much is known about the partition function, little is known about its parity. For the polynomials D ( x ) : = ( D x 2 + 1 ) / 24 , where D ≡ 23 ( mod 24 ) , we show that there are infinitely many m (resp. n ) for which p ( D ( m ) ) is even (resp. p ( D ( n ) ) is odd) if there is at least one such m (resp. n ). We bound the first m and n (if any) in terms of the class number h ( − D ) . For prime D we show that there are indeed infinitely many even values. To this end we construct new modular generating functions using generalized Borcherds products , and we employ Galois representations and locally nilpotent Hecke algebras.
Sons, Daughters, and Parental Behaviour

The prevalence of son preference and its implications for family behaviour in developing countries have received a great deal of scholarly attention, but child-gender bias is believed to be empirically unimportant in wealthy, non-traditional societies. Studies by sociologists and psychologists during the past 30 years, however, have documented consistent discrepancies between the behaviour of parents of sons and parents of daughters--boys tend to increase marital stability and marital satisfaction relative to girls, and fathers spend more time with, and are more involved with, sons than daughters. In recent years, economists have begun to contribute to the child-gender literature, re-examining the effects of sons and daughters on family structure and parental involvement with larger samples and greater concern for possible sources of selection bias. Other economic outcomes, such as market work and earnings, have also been studied, and some investigators have exploited the randomness of child gender as a source of exogenous variation in parental behaviour. In general, recent results suggest that child gender does affect family stability and the time allocation of parents, but it is not clear whether these responses reflect parental preferences for boys rather than girls or differences in the constraints parents face. Copyright 2005, Oxford University Press.
Enantioselective Route to Platensimycin: An Intramolecular Robinson Annulation Approach

An enantioselective route to the tetracyclic core structure of the novel antibiotic lead compound platensimycin is accomplished in 10 steps from simple commercially available starting materials. Highlights of this synthesis include (1) a regio- and enantioselective Diels−Alder reaction between methyl acrylate and methyl cyclopentadiene to give adduct 2 with essentially complete regio-, diastereo-, and enantiocontrol; (2) oxidative decarboxylation of ester 2 using nitrosobenzene; (3) a one-pot reductive cyanation of lactone 4; (4) a stereoselective intramolecular Michael addition between an α-branched aldehyde moiety and a β-substituted enone part of 8, followed by aldol dehydration in one pot to give the Robinson annulation product 9.
A simple and efficient chemoselective method for the catalytic deprotection of acetals and ketals using bismuth triflate.

Bismuth triflate is a highly efficient catalyst (0.1−1 mol %) for the deprotection of acetals and ketals. The procedure is very facile and selective for acetals derived from ketones and conjugated aldehydes. tert-Butyldimethylsilyl ethers are stable to the reaction conditions. The highly catalytic nature of bismuth triflate and the use of a relatively nontoxic solvent system (THF/H2O) make this procedure particularly attractive for large-scale synthesis.
The Nova Control System – Goals, Architecture, and System Design

Abstract The Nova laser fusion facility is presently under construction at LLNL.- It is a large glass laser, generating 150 trillion watt pulses of infrared light at a wavelength of 1 micrometer ( μ )· Nova will achieve these energy levels using 10 amplifier chains, each focused onto fusion targets a few millimeters in diameter. Conversion of the 1 μ light to shorter wavelengths of 0.5 μ and 0.35 μ is expected to allow Nova to perform experiments in the physics regime of thermonuclear ignition. The control system for the Nova laser must operate reliably in a harsh pulse power environment and satisfy requirements of technical functionality, flexibility, maintainability and operability. It is composed of four fundamental subsystems: Power Conditioning, Alignment, Laser Diagnostics, and Target Diagnostics, together with a fifth, unifying subsystem called Central Controls. The system architecture utilizes a collection of distributed microcomputers, minicomputers, and components interconnected through high speed fiber optic communications systems. The design objectives, development strategy and architecture of the overall control system and each of its four fundamental subsystems are discussed. Specific hardware and software developments in several areas are also covered.
Syntheses, structures, and properties of dipyridazino-fused 1 ,3,4,6-tetraazapentalenes

Abstract The fluorescent 2,9-dichloro[2' ,3':1' ,2' imidazo[4',5',:4,5] imidazo-[1,2- b ]pyridazine (2a) and the unsubstituted “parent” 2b have been synthesized. The chloro groups of 2a Were found to be easily displaced by a variety of nucleophiles to provide the 2,9-disubstituted compounds 7–12. A single crystal X-ray structure determination of the 2,9-dimethoxy-substituted compound 7 revealed the existence of two crystallographically independent structures in the unit cell. It has been demonstrated that 2b can form a 2:1 complex with cobalt(II).
Naturalness and Higgs decays in the MSSM with a singlet

The simplest extension of the supersymmetric standard model--the addition of one singlet superfield--can have a profound impact on the Higgs and its decays. We perform a general operator analysis of this scenario, focusing on the phenomenologically distinct scenarios that can arise, and not restricting the scope to the narrow framework of the NMSSM. We reexamine decays to four b quarks and four {tau}'s, finding that they are still generally viable, but at the edge of LEP limits. We find a broad set of Higgs decay modes, some new, including those with four gluon final states, as well as more general six and eight parton final states. We find the phenomenology of these scenarios is dramatically impacted by operators typically ignored, specifically those arising from D-terms in the hidden sector, and those arising from weak-scale colored fields. In addition to sensitivity of m{sub z}, there are potential tunings of other aspects of the spectrum. In spite of this, these models can be very natural, with light stops and a Higgs as light as 82 GeV. These scenarios motivate further analyses of LEP data as well as studies of the detection capabilities of future colliders to the new decay channels presented.
Self-consistent simulation of turbulence and transport in Tokamak edge plasmas

The status of coupling the fluid 3D turbulence code BOUT and the fluid plasma/neutral 2D transport code UEDGE is reported, where both codes simulate the edge region of diverted tokamaks from several cm inside the magnetic separatrix to the far scrape-off layer (SOL), thereby including the magnetic X-point. Because the characteristic time scale of the turbulence is short (∼ 10 -5 - 10 -4 s) and the profile evolution time scale can be long (∼ 10 -2 - 10 -1 s owing to recycling), an iterative scheme is used that relaxes the turbulent fluxes passed from BOUT to LEDGE and the profiles from UEDGE to BOUT over many coupling steps. Each code is run on its own characteristic time scale, yielding a statistically averaged steady state. For this initial study, the ion and neutral densities and parallel velocities are evolved, while the temperature profiles are stationary. Here the turbulence code is run in the electrostatic approximation. For this example of self-consistent coupling with strong L-mode-like turbulence, the ion flux to the main-chamber exceeds that to the divertor plates.
Levi decompositions of a linear algebraic group

If G is a connected linear algebraic group over the field k, a Levi factor of G is a reductive complement to the unipotent radical of G. If k has positive characteristic, G may have no Levi factor, or G may have Levi factors which are not geometrically conjugate. In this paper we give some sufficient conditions for the existence and conjugacy of the Levi factors of G.
Aerodynamic performance of an annular flat plate airfoil cascade with nonuniform inlet velocity

The demand for increased gas turbine engine efficiency with minimum weight is leading to more complex blading designs, in which viscous and three-dimensional effects are significant. As a result, design procedures based on first principle, experimentally verified, three-dimensional aerodynamic analyses are required. This paper describes a series of experiments performed in a large-scale, subsonic, annular cascade facility specifically designed to provide three-dimensional aerodynamic data suitable for code verification. In particular, the effect of inlet velocity profile on the overall three-dimensional performance of a classical flat plate airfoil cascade is investigated over a range of incidence angles including those resulting in airfoil surface flow separation. All of the data are analyzed and correlated with appropriate nonseparated flow predictions.
Further evidence for the tetraoxoiodate(V) anion, IO43-: Hydrothermal syntheses and structures of Ba[(MoO2)6(IO4)2O4].H2O and Ba3[(MoO2)2(IO6)2].2H2O

The hydrothermal reaction of MoO3 with BaH3IO6 at 180 °C for 3 days results in the formation of Ba[(MoO2)6(IO4)2O4]·H2O (1). Under similar conditions, the reaction of Ba(OH)2·8H2O with MoO3 and Ba(IO4)2·6H2O yields Ba3[(MoO2)2(IO6)2]·2H2O (2). The structure of 1, determined by single-crystal X-ray diffraction, consists of corner- and edge-sharing distorted MoO6 octahedra that create two-dimensional slabs. Contained within this molybdenum oxide framework are approximately C2v tetraoxoiodate(V) anions, IO43-, that are involved in bonding with five Mo(VI) centers. The two equatorial oxygen atoms of the IO43- anion chelate a single Mo(VI) center, whereas the axial atoms are μ3-oxo groups and complete the octahedra of four MoO6 units. The coordination of the tetraoxoiodate(V) anion to these five highly electropositive centers is probably responsible for stabilizing the substantial anionic charge of this anion. The Ba2+ cations separate the layers from one another and form long ionic contacts with neighboring o...
Development of a Compensation Chamber for Use in a Multiple Condenser Loop Heat Pipe

We report the design and analysis of a novel compensation chamber for use in PHUMP, a multiple condenser loop heat pipe (LHP) capable of dissipating 1000 W. The LHP is designed for integration into a high performance air-cooled heat sink to address thermal management challenges in advanced electronic systems. The compensation chamber is integrated into the evaporator of the device and provides a region for volumetric expansion of the working fluid over a range of operating temperatures. Additionally, the compensation chamber serves to set the liquid side pressure of the device, preventing both flooding of the condensers and dry out of the evaporator. The compensation chamber design was achieved through a combination of computational simulation using COMSOL Multiphysics and models developed based on experimental work of previous designs. The compensation chamber was fabricated as part of the evaporator using Copper and Monel sintered wicks with various particle sizes to achieve the desired operating characteristics. Currently, the compensation chamber is being incorporated into a multiple condenser LHP for a high performance air-cooled heat sink.Copyright © 2013 by ASME
Object tracking through adaptive correlation

Current Air Force interests include a desire to track an object based on its shape once it has been designated as a target. The use of a correlation-based system to track an object through a series of images based on templates derived from previous image frames is discussed. The ability to track is extended to sequences that include multiple objects of interest within the field of view. This is accomplished by comparing the height and shape of the template autocorrelation to the peaks in the correlation of the template with the next scene. The result is to identify the region in the next scene that best matches the designated target. In addition to correlation plane postprocessing, an adaptive window is used to determine the template size to reduce the effects of correlator walkoff. The image sequences used were taken from a forward-looking infrared sensor mounted on board a DC-3 aircraft. The images contain a T-55 tank and both an M-113 and a TAB-71 armored personnel carrier moving in a columnized formation along a dirt road. This research presents techniques to (1) track targets in the presence of other, and sometimes brighter, targets of similar shape, (2) to maintain small tracking errors, and (3) to reduce the effects of correlator walk-off.
Preliminary Results of Improved Model Fits to the Extreme and Far UV Observations of Cataclysmic Variables

We present the first results of a study which will attempt to analyze the combined Voyager and IUE observations of cataclysmic variables using steady-state accretion disk models. Initially we use flux ratio diagrams to determine if a combination of models will suffice or if new ingredients are necessary.
Physical Human Interactive Guidance: Identifying Grasping Principles From Human-Planned Grasps

We present a novel and simple experimental method called physical human interactive guidance to study human-planned grasping. Instead of studying how the human uses his/her own biological hand or how a human teleoperates a robot hand in a grasping task, the method involves a human interacting physically with a robot arm and hand, carefully moving and guiding the robot into the grasping pose, while the robot's configuration is recorded. Analysis of the grasps from this simple method has produced two interesting results. First, the grasps produced by this method perform better than grasps generated through a state-of-the-art automated grasp planner. Second, this method when combined with a detailed statistical analysis using a variety of grasp measures (physics-based heuristics considered critical for a good grasp) offered insights into how the human grasping method is similar or different from automated grasping synthesis techniques. Specifically, data from the physical human interactive guidance method showed that the human-planned grasping method provides grasps that are similar to grasps from a state-of-the-art automated grasp planner, but differed in one key aspect. The robot wrists were aligned with the object's principal axes in the human-planned grasps (termed low skewness in this paper), while the automated grasps used arbitrary wrist orientation. Preliminary tests show that grasps with low skewness were significantly more robust than grasps with high skewness (77-93%). We conclude with a detailed discussion of how the physical human interactive guidance method relates to existing methods to extract the human principles for physical interaction.
On the Use of the Hole-Drilling Technique for Residual Stress Measurements in Thin Plates

The strain gage blind hole-drilling technique may be used to determine residual stresses at and below the surface of components. In this paper, the hole-drilling analysis methodology for thick plates is reviewed, and experimental data are used to evaluate the methodology and to assess its applicability to thin plates. Data on the effects of gage pattern, surface preparation, hole spacing, hole eccentricity, and stress level are also presented.
PeV cosmic rays: A Window on the leptonic era?

Abstract It is shown that a variety of characteristic features of the high-energy hadronic cosmic-ray spectra, in particular the abrupt changes in the spectral index that occur around 3 and 300 PeV, as well as the corresponding changes in elemental composition that are evident from kinks in the 〈Xmax〉 distribution, can be explained in great detail from interactions with relic Big Bang antineutrinos, provided that the latter have a rest mass of ∼0.5 eV/c2.
The value in musculoskeletal care: summary and recommendations.

Musculoskeletal diseases can be lifelong and affect and be affected by other health conditions. With their resulting pain and impact on loss of function and mobility, they can affect efforts to control hypertension, diabetes, obesity, and other conditions. They can impact the ability to maximize educational opportunities, earn a living, care for family, and participate in or contribute to other activities associated with a fulfilling life. Tremendous advances have been made in understanding the etiology and identifying treatment options for the vast majority of these conditions. However, understanding and defining the value of these various treatment options to patients, their families, and society are areas that have not been fully examined. Health care reform has drawn our attention to this gaping hole in our knowledge and provides us with an opportunity to look for answers and contribute to the debate that is underway to ensure that resources are allocated to best meet patient needs. An interdisciplinary Summit (www.usbji.org/rd/? MSKSummit) organized by the US Bone and Joint Initiative
The Incidence of the Healthcare Costs of Obesity

Who pays the healthcare costs associated with obesity? Among workers, this is largely a question of the incidence of the costs of employer-sponsored coverage. Using data from the National Longitudinal Survey of Youth and the Medical Expenditure Panel Survey, we find that the incremental healthcare costs associated with obesity are passed on to obese workers with employer-sponsored health insurance in the form of lower cash wages. Obese workers without employer-sponsored insurance do not have a wage offset relative to their non-obese counterparts. A substantial part of the lower wages among obese women attributed to labor market discrimination can be explained by their higher health insurance premiums.