cssi/SciSciGPT-SciSciNet huggingface dataset:
Determination of aerodynamic sensitivity coefficients based on the transonic small perturbation formulation

The quasianalytical approach is developed to compute airfoil aerodynamic sensitivity coefficients in the transonic and supersonic flight regimes. Initial investigation verifies the feasibility of this approach as applied to the transonic small perturbation residual expression. Results are compared to those obtained by the direct (finite difference) approach, and both methods are evaluated to determine their computational accuracies and efficiencies
An investigation of surface albedo variations during the recent Sahel drought

Applications Technology Satellite 3 green sensor data were used to measure surface reflectance variations in the Sahara/Sahel during the recent drought period; 1967 to 1974. The magnitude of the seasonal reflectance change is shown to be as much as 80% for years of normal precipitation and less than 50% for drought years. Year to year comparisons during both wet and dry seasons reveal the existence of a surface reflectance cycle coincident with the drought intensity. The relationship between the green reflectance and solar albedo is examined and estimated to be about 0.6 times the reflectance change observed by the green channel.
Competing Risk Analysis of Men Aged 55 to 74 Years at Diagnosis Managed Conservatively for Clinically Localized Prostate Cancer

Context.— The appropriate therapy for men with localized prostate cancer is uncertain. Until results of clinical trials are available, men and their physicians need guidance. Objective.— To estimate survival based on a competing risk analysis stratified by age at diagnosis and histologic findings for men diagnosed as having clinically localized prostate cancer and who were managed conservatively. Design.— Retrospective cohort study. Setting.— Connecticut Tumor Registry. Patients.— A total of 767 men with localized prostate cancer diagnosed between 1971 and 1984, aged 55 to 74 years at diagnosis, either not treated or treated with immediate or delayed hormonal therapy, and followed up for 10 to 20 years after diagnosis. Main Outcome Measures.— Estimates of the probability of dying from prostate cancer or other competing hazards. Results.— Men with tumors that have Gleason scores of 2 to 4, 5, 6, 7, and 8 to 10 face a 4% to 7%, 6% to 11%, 18% to 30%, 42% to 70%, and 60% to 87% chance, respectively, of dying from prostate cancer within 15 years of diagnosis depending on their age at diagnosis. Conclusions.— Men whose prostate biopsy specimens show Gleason score 2 to 4 disease face a minimal risk of death from prostate cancer within 15 years of diagnosis. Conversely, men whose biopsy specimens show Gleason score 7 to 10 disease face a high risk of death from prostate cancer when treated conservatively, even when cancer is diagnosed as late as age 74 years. Men with Gleason score 5 or 6 tumors face a modest risk of death from prostate cancer that increases slowly over at least 15 years of follow-up.
Radiation Enhancement by Nonequilibrium in Earth's Atmosphere

The status of knowledge of shock-layer radiation in the low-density nonequilibrium regime, as appropriate to the flight of the proposed aeroassisted orbital transfer vehicle, is surveyed. The existing laboratory data and the flight data from Apollo and Fire are scrutinized. Nonequilibrium radiation is found to be significant in the flight regime of the vehicle, but a factor-of-thre e uncertainty is found in its magnitude. The available theoretical models are reviewed, their weaknesses are pointed out, a computer code that approximately reproduces the existing data is introduced, and recommendations are made for future research.
Super elliptic curves

Abstract A detailed study is made of super elliptic curves, namely super Riemann surfaces of genus one considered as algebraic varieties, particularly their relation with their Picard groups. This is the simplest setting in which to study the geometric consequences of the fact that certain cohomology groups of super Riemann surfaces with odd spin structure are not freely generated modules. The divisor theory of Rosly, Schwarz, and Voronov gives a map from a supertorus to its Picard group Pic, but this map is a projection, not an isomorphism as it is for ordinaty tori. The geometric realization of the addition law on Pic via intersections of the supertorus with superlines in projective space is described. The isomorphisms of Pic with the Jacobian and the divisor class group are verified. All possible isogenies, or surjective holomorphic maps between supertori, are determined and shown to induce homomorphisms of the Picard groups. Finally, the solutions to the new super Kadomtsev-Petviashvili hierarchy of Mulase-Rabin which arise from super elliptic curves via the Krichever construction are exhibited.
Associative diblock copolymers of poly(ethylene glycol) and coiled-coil peptides

A series of peptides of general primary structure (VSSLESK) n (n=2, 3, 4, 5 and 6) were designed and synthesized by fluorenylmethyloxycarbonyl solid-phase synthesis using a convergent approach. Peptides containing 21, 28, 35 and 42 residues were modified with α-methoxy poly-(ethylene glycol) (mPEG; mol. wt. 2000) by reaction of mPEG-succinimidyl carbonate with the α-amino group of the resin-attached protected peptides. The conformation and thermal stability of the peptides and of their AB block copolymers (A is the mPEG block, B the (VSSLESK) n block) in aqueous medium were investigated by circular dichroism, size-exclusion chromotography and by analytical ultracentrifugation. The helicity of peptides increased with increasing length in a cooperative manner. The peptides and mPEG-peptides with 35 and 42 amino acid residues (block copolymers) adopted a two-stranded α-helical coiled-coil conformation in aqueous solution. The presence of the polymer chain in the diblock hybrid copolymers had no disturbing effect with respect to the stability of the α-helical peptide part in these constructs. Moreover, the thermal stability of mPEG-modified 42-peptide was substantially higher than that of the native 42-peptide. Analytical ultracentrifugation data revealed that in phosphate-buffered saline solution (25-200 μM) the block copolymer mPEG-block-(VSSLESK) 6 (PEG42) associated into stable intermolecular coiled-coil dimers.
Halo Models of Large Scale Structure

Abstract We review the formalism and applications of the halo-based description of non-linear gravitational clustering. In this approach, all mass is associated with virialized dark matter halos; models of the number and spatial distribution of the halos, and the distribution of dark matter within each halo, are used to provide estimates of how the statistical properties of large scale density and velocity fields evolve as a result of non-linear gravitational clustering. We first describe the model, and demonstrate its accuracy by comparing its predictions with exact results from numerical simulations of non-linear gravitational clustering. We then present several astrophysical applications of the halo model: these include models of the spatial distribution of galaxies, the non-linear velocity, momentum and pressure fields, descriptions of weak gravitational lensing, and estimates of secondary contributions to temperature fluctuations in the cosmic microwave background.
Factors Influencing Selection Of A Next-Generation Telescope Concept

In the early 1960s farsighted astronomers recommended a study of a very large optical telescope that would provide a major advance in light-gathering power over the Palomar 5-meter telescope. Large telescopes are expensive, however, and for a time, great gains in performance were more easily obtained by developing better detectors, or more efficient diffraction gratings or high performance reflective mirror coatings. Computers came into vogue and enabled better data extraction and analysis as well as increasing the number of observations that could be made in a given period of time. Daytime usage of telescopes for infrared astronomy became commonplace, thus extending the available observing time.
Growth, deforestation and the efficiency of the REDD mechanism

This paper assesses the long term impacts of an international transfer called the Reduced Emissions from Deforestation and Degradation (REDD) mechanism, which aims at preserving tropical forests of the recipient economy. This two-sector economy faces a dilemma between economic growth and deforestation. The rural sector can substitute reproducible capital for agricultural land whereas the manufacturing sector only requires capital. The model shows that the REDD mechanism has a non-monotonic effect on steady state welfares. For low transfer schemes, the agricultural output increases with the transfer even though less land is under cultivation. For high transfer schemes, the increase in the transfer may not offset the decrease in the agricultural output. The open-loop symmetric Nash equilibrium in a dynamic deforestation game predicts that redistributing the transfer among a finite number of producers is less efficient in reducing deforestation than in the social optimum.
Constraints on the cosmic neutrino background

The radiative component of the Universe has a characteristic impact on both large-scale structure (LSS) and the cosmic microwave background radiation (CMB). We use the recent WMAP data, together with previous Cosmic Background Imager (CBI) data and 2dF matter power spectrum, to constrain the effective number of neutrino species N e f f in a general cosmology. We find that N e f f = 4.31 with a 95 per cent confidence limit 1.6 ≤ N e f f ≤ 7.1. If we include the H 0 prior from the HST project we find the best fit N e f f = 4.08 and 1.90 ≤ N e f f ≤ 6.62 for a 95 per cent confidence limit. The curvature we derive is still consistent with flat, but assuming a flat Universe from the beginning implies a bias toward lower N e f f , as well as artificially smaller error bars. Adding the supernova constraint does not improve the result. We analyse and discuss the degeneracies with other parameters, and point out that probes of the matter power spectrum on smaller scales and accurate independent σ 8 measurements, together with better independent measurement of H 0 , would help in breaking the degeneracies.
Using Hook Schur Functions to Compute Matrix Cocharacters

We develop a new integration method based on hook Schur functions instead of Schur functions to compute the cocharacters of matrices. We then use this method to compute some of the multiplicities in the cocharacter sequence of 3 × 3 matrices.
Using irregularly spaced returns to estimate multi-factor models: application to Brazilian equity data

Abstract Multi-factor models are useful tools to explain cross-sectional covariance in equities returns. In this paper a new estimation method is proposed that makes use of irregularly spaced returns and an empirical example is provided with the 389 most liquid equities in the Brazilian Market. The market index shows itself capable of explaining equity returns while the US$/Brazilian real exchange rate and the Brazilian short interest rate do not. The example shows the usefulness of the estimation method in further using the model to fill in missing values and to provide interval forecasts.
Vinogradov's Integral and Bounds for the Riemann Zeta Function

The main result is an upper bound for the Riemann zeta function in the critical strip: $2000 Mathematical Subject Classification: primary 11M06, 11N05, 11L15; secondary 11D72, 11M35.
Prediction of Extraprostatic Extension of Prostate Cancer Based on Needle Biopsy Findings: Perineural Invasion Lacks Significance on Multivariate Analysis

Extraprostatic extension (EPE) and seminal vesicle invasion (SVI) are adverse prognostic factors in prostate cancer, and their prediction before prostatectomy would be useful. Perineural invasion in needle biopsy has been advocated as a marker of extraprostatic extension, but its independent value a
76-space analysis of grey matter diffusivity: methods and applications.

Abstract Diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) allow in vivo investigation of molecular motion of tissue water at a microscopic level in cerebral gray matter (GM) and white matter (WM). DWI/DTI measure of water diffusion has been proven to be invaluable for the study of many neurodegenerative diseases (e.g., Alzheimer's disease and Creutzfeldt–Jakob disease) that predominantly involve GM. Thus, quantitative analysis of GM diffusivity is of scientific interest and is promised to have a clinical impact on the investigation of normal brain aging and neuropathology. In this paper, we propose an automated framework for analysis of GM diffusivity in 76 standard anatomic subdivisions of gray matter to facilitate studies of neurodegenerative and other gray matter neurological diseases. The computational framework includes three enabling technologies: (1) automatic parcellation of structural MRI GM into 76 precisely defined neuroanatomic subregions (“76-space”), (2) automated segmentation of GM, WM and CSF based on DTI data, and (3) automatic measurement of the average apparent diffusion coefficient (ADC) in each segmented GM subregion. We evaluate and validate this computational framework for 76-space GM diffusivity analysis using data from normal volunteers and from patients with Creutzfeldt–Jakob disease.
Magnetic Field Amplification and Rapid Time Variations in SNR RX J1713.7–3946

Evidence is accumulating suggesting that collisionless shocks in supernova remnants (SNRs) can amplify the interstellar magnetic field to hundreds of microgauss or even milligauss levels, as recently claimed for SNR RX J1713.7–3946. If these fields exist, they are almost certainly created by magnetic field amplification (MFA) associated with the efficient production of cosmic rays by diffusive shock acceleration (DSA) and their existence strengthens the case for SNRs being the primary source of Galactic cosmic-ray ions to the "knee" and beyond. However, the high magnetic field values in SNRs are obtained exclusively from the interpretation of observations of radiation from relativistic electrons, and if MFA via nonlinear DSA produces these fields, the magnetic field that determines the maximum ion energy will be substantially less than the field that determines the maximum electron energy. We use results of a steady-state Monte Carlo simulation to show how nonlinear effects from efficient cosmic-ray production and MFA reduce the maximum energy of protons relative to what would be expected from test-particle acceleration.
Sphincter pharyngoplasty: speech outcome and complications

Objectives To assess the speech outcomes and complications in children who had undergone sphincter pharyngoplasty (SP) for management of velopharyngeal insufficiency (VPI). Study design Retrospective chart review. Methods Charts from patients who had sphincter pharyngoplasty between January 1993 and June 1996 were reviewed. Syndrome diagnosis and presence of repaired cleft palate were reviewed. Preoperative speech assessment, videofluoroscopic and nasopharyngoscopic evaluations, age at time of surgery, and postoperative speech assessments were reviewed for all patients. Postoperative videofluoroscopy and nasopharyngoscopy were performed for those patients who had persistent VPI. Obstructive sleep symptoms were also assessed. Results Thirty patients were identified; six patients had no follow-up evaluation, leaving 24 patients included in this study. Average follow-up was 11.7 months (range, 2-35 mo). Velocardiofacial syndrome (VCFS) was the most commonly identified syndrome. Postoperatively, 15 of 24 patients (62.5%) had complete resolution of their VPI; five of 24 (20.8%) had significant improvement; one of 24 (4.2%) had minimal to no change; and three of 24 (12.5%) were hyponasal. Of the six patients with some degree of persistent VPI, three underwent revision surgery. All three patients had complete resolution of their VPI after revision surgery, resulting in an overall success rate of 18 of 24 (75%). Conclusions Sphincter pharyngoplasty has wide application in the management of children with VPI, including those with VCFS. The procedure is readily modified to accommodate an individual patient's needs as determined by preoperative VPI evaluation. A modification of the procedure is described to minimize the risk of postoperative airway obstruction and hyponasality, both regarded as airway complications of sphincter pharyngoplasty.
Opening an Aladdin's cave: the Suzuki coupling in a room-temperature ionic liquid

This viewpoint will discuss the impact of the 2000 Chem. Commun. report that the palladium-catalysed Suzuki coupling can be performed quickly and easily in a room-temperature ionic liquid. This work has helped fuel what have now become whole areas of chemistry of their own: the use of ionic liquids as reaction media for catalytic transformations, and the application of palladium complexes bearing N-heterocyclic carbene (NHC) ligands in the Suzuki coupling and beyond.
Indeterminacy, Bubbles, and the Fiscal Theory of Price Level Determination

Abstract The recently developed fiscal theory of price level determination contends that there is an important class of policy rules in which there exists a unique rational expectations solution that shows the price level to be dependent upon fiscal policy and independent of monetary variables. The present paper argues, however, that there is an alternative solution to these models that has entirely traditional (or ‘monetarist’) properties. This latter solution is arguably more plausible since it is the solution that is typically regarded as the bubble-free ‘fundamentals’ solution. The paper's analysis involves the specification of feasible instrument variables.
Strong solutions of stochastic equations with rank-based coefficients

We study finite and countably infinite systems of stochastic differential equations, in which the drift and diffusion coefficients of each component (particle) are determined by its rank in the vector of all components of the solution. We show that strong existence and uniqueness hold until the first time three particles collide. Motivated by this result, we improve significantly the existing conditions for the absence of such triple collisions in the case of finite-dimensional systems, and provide the first condition of this type for systems with a countable infinity of particles.
Rebound hypertension after discontinuation of transdermal clonidine therapy

Abstract Three (and possibly all four) elderly hypertensive patients who were followed sequentially after discontinuation of transdermal clonidine monotherapy manifested a rapid rise in blood pressure to levels above control (pre- and post-therapy) readings. No signs of an "overshoot" in plasma norepinephrine levels or symptoms of beta-adrenergic overactivity were seen. Such rebound hypertension suggests hypersensitivity to alpha-adrenergic receptor stimulation and could pose a heretofore unreported potential hazard to elderly or otherwise compromised patients who discontinue transdermal clonidine therapy.
Cu(II)-mediated oxidative dimerization of 2-phenylpyridine derivatives

A Cu(II)/I2-mediated C–H bond activation is described. A variety of 2-phenylpyridine derivatives are oxidatively dimerized at the ortho-position of the phenyl ring in which a net loss of two hydrogen atoms results in the formation of a biaryl compound via a double C–H activation/C–C bond-forming process. Moderate functional group tolerance was observed on both the aryl and the pyridyl rings. A single electron transfer (SET) or electrophilic metalation process for iodination followed by Ullmann coupling of the intermediate iodinated product is proposed as the operating mechanism for the dimerization process.
A Selective and Efficient Method for the Deprotection of N-Benzyloxymethyl (BOM) Protecting Groups from Pyrimidine and Dihydropyrimidine Ring Systems

Abstract N1,N3-dibenzyloxymethyl derivatives of pyrimidines and dihydropyrimidines have been successfully deprotected by using trifluoroacetic acid (TFA). These N-BOM derivatives can be selectively removed from a variety of derivatives including nucleosides and compounds which are sensitive to base and reducing conditions.
A direct proof of a theorem of Blaschke and Lebesgue

The Blaschke-Lebesgue Theorem states that among all planar convex domains of given constant width B the Reuleaux triangle has minimal area. It is the purpose of this article to give a direct proof of this theorem by analyzing the underlying variational problem. The advantages of the proof are that it shows uniqueness (modulo rigid deformations such as rotation and translation) and leads analytically to the shape of the area-minimizing domain. Most previous proofs have relied on foreknowledge of the minimizing domain. Key parts of the analysis extend to the higher-dimensional situation, where the convex body of given constant width and minimal volume is unknown.
Religious Diversity and Religious Tolerance: Lessons from Nigeria

This article seeks to understand the impact of religious diversity on religious tolerance in developing countries and draws lessons from the case of Nigeria. Religious diversity has appeared to prompt religious intolerance in Nigeria when we view the country from a distance. However, this article reveals important subnational variation. Using original survey data collected in 2006, I compare the impact of religious observance on respect for religious freedom across four settings within Nigeria and find religious observance was having, at the time of the survey, a more positive impact on respect for religious freedom in the most religiously diverse and integrated of the four settings. In-depth interviews indicate that Christian and Muslim religious leaders more openly encouraged religious tolerance in religiously diverse and integrated settings than in religiously homogenous settings. Substantively, this study suggests that religious segregation rather than religious diversity has inhibited religious toler...
Mechanism for reduction catalysis by metal oxo: hydrosilation of organic carbonyl groups catalyzed by a rhenium(V) oxo complex.

The rhenium oxo complex [Re(O)(hoz)2][TFPB], 1 (where hoz = 2-(2‘-hydroxyphenyl)-2-oxazoline(−) and TFPB = tetrakis(pentafluorophenyl)borate) catalyzes the hydrosilation of aldehydes and ketones under ambient temperature and atmosphere. The major organic product is the protected alcohol as silyl ether. Isolated yields range from 86 to 57%. The reaction requires low catalyst loading (0.1 mol %) and proceeds smoothly in CH2Cl2 as well as neat without solvent. In the latter condition, the catalyst precipitates at the end of reaction, allowing easy separation and catalyst recycling. Re(O)(hoz)(H), 3, was prepared, and its involvement in an ionic hydrosilation mechanism was evaluated. Complex 3 was found to be less hydridic than Et3SiH, refuting its participation in catalysis. A viable mechanism that is consistent with experimental findings, rate measurements, and kinetic isotope effects (Et3SiH/Et3SiD = 1.3 and benzaldehyde-H/benzaldehyde-D = 1.0) is proposed. Organosilane is activated via η2-coordination to ...
Underfunding pension obligations while paying dividends: evidence of risk transfers

Abstract This research examines the differential effects of earnings, dividends, and cashflows on increases and decreases in pension liabilities. Of the 1700 firms in the Value Line Investment Survey (1997a), there were 189 firms with pension liabilities—88 (101) firms with increasing (decreasing) pension liabilities that serve as research observations. For firms with increasing pension liabilities, there is a significant correlation between the increase in pension liabilities and earnings, cashflows, and dividends. However, none of these relationships exist for firms with decreasing pension liabilities. The underfunding of pension funds is a unilateral decision by management that effectively transfers risk away from stockholders and imposes it on employees and potentially on the society at large. This risk transfer is not associated with any compensatory returns and suggests social and regulatory policies should be reconsidered.
Effect of silicon carbide fiber or whisker reinforcement on the thermal diffusivity/conductivity of an osumilite glass-ceramic

The thermal diffusivity of silicon carbide fiber- and whisker-reinforced osumilite glass-ceramic was determined by the laser-flash method. The thermal conductivity was calculated from the data of thermal diffusivity, density, and specific heat measured by differential scanning calorimetry. Because of the much higher thermal conductivity of the crystalline silicon carbide whiskers compared to the corresponding value for the amorphous fibers, the whisker-reinforced composites exhibited significantly higher thermal diffusivity and thermal conductivity than the fiber-reinforced composites.
Intrinsic charm contribution to double quarkonium hadroproduction

Abstract Double J ψ production has been observed by the NA3 collaboration in πN and pN collisions with a cross section of the order of 20–30 pb. The ψψ pairs measured in π− nucleus interactions at 150 and 280 GeV/c are observed to carry an anomalously large fraction of the projectile momentum in the laboratory frame, xψψ >- 0.6 at 150 GeV/c and >- 0.4 at 280 GeV/c. We postulate that these forward ψψ pairs are created by the materialization of Fock states in the projectile containing two pairs of intrinsic c c quarks We calculate the overlap of the charmonium states with the | u dc c c c 〉 Fock state as described by the intrinsic charm model and find that the π− N → ψψ longitudinal momentum and invariant mass distributions are both well reproduced. We also discuss double J ψ production in pN interactions and the implications for other heavy quarkonium production channels in QCD.
QRE, NSNX and the Paradox of Voting

Levine and Palfrey's QRE account of turnout in large elections raises the broader question of how much of a departure from standard rational choice theory is justified by the considerable repertoire of rational choice anomalies that has accumulated since Downs and Olson half a century ago. An alternative but more controversial unconventional view turns on what I call NSNX motivation to account for how agents seek a balance between self-interest and social motivation. NSNX agents have irreducibly dual utility functions. QRE agents have a standard utility function but they do not maximize it. I review the situation showing why in situations where NSNX effects could be expected, QRE might mirror those effects. I show how, by varying parameters of an experiment, I can cleanly distinguish between actual QRE effects, which should bring predictions closer to the data than Nash, and NSNX effects, which should do the same.
NO STRIPPED HYDROGEN IN THE NEBULAR SPECTRA OF NEARBY TYPE Ia SUPERNOVA 2011fe

A generic prediction of the single-degenerate model for Type Ia supernovae (SNe Ia) is that a significant amount of material will be stripped from the donor star (~0.5 M ☉ for a giant donor and ~0.15 M ☉ for a main-sequence donor) by the supernova ejecta. This material, excited by gamma-rays from radioactive decay, would then produce relatively narrow (1000 km s–1) emission features observable once the supernova enters the nebular phase. Such emission has never been detected, which already provides strong constraints on Type Ia progenitor models. In this Letter, we report the deepest limit yet on the presence of Hα emission originating from the stripped hydrogen in the nebular spectrum of an SN Ia obtained using a high signal-to-noise spectrum of the nearby normal SN Ia 2011fe 274 days after B-band maximum light with the Large Binocular Telescope's Multi-Object Double Spectrograph. We put a conservative upper limit on the Hα flux of 3.14 × 10–17 erg s–1 cm–2, which corresponds to a luminosity of 1.57 × 1035 erg s–1. By scaling models from the literature, our flux limit translates into an upper limit of 0.001 M ☉ of stripped material. This is an order of magnitude stronger than previous limits. SN 2011fe was a typical SN Ia, special only in its proximity, and we argue that lack of hydrogen emission in its nebular spectrum adds yet another strong constraint on the single-degenerate class of models for SNe Ia.
Historical aerial photographs and a Geographic Information System (GIS) to determine effects of long-term water level fluctuations on wetlands along the St. Marys River, Michigan, USA.

Abstract The water levels of the Great Lakes fluctuate as much as ± 1 m from their respective long-range mean elevations in response to changes in climatic conditions. Coastal wetland areas on each Great Lake expand or contract in response to the long-term water level fluctuations. The water level of the St. Marys River, a connecting channel between Lakes Superior and Huron, is largely controlled by the level of Lake Huron. The St. Marys River wetlands expand and contract in a fashion similar to wetlands on the lakes. Data on St. Marys River wetland areas were derived from historical aerial photographs and placed in a Geographic Information System (GIS) to analyze the effects of water level fluctuations. The GIS was used to measure wetland area changes between the years for which photographic data were available. Use of GIS allowed quantification of wetland area changes, estimation of response rates and description of inter-class transfer dynamics, for five coastal wetland classes influenced by long-term water level fluctuations.
Reactions of (μ-PhPLi)2Fe2(CO)6 with metal halides†

Metal carbonyl cluster complexes containing iron, phenylphosphido units and another metal (Ni, Pd, Pt, Co, Hg) have been prepared by reactions of (μ-PhPLi)2Fe2(CO)6 with metal halides and (μ-PhPH)2Fe2(CO)6 with zerovalent metal complexes.
The Voice of Conscience

I reconstruct Kant's derivation of the Categorical Imperative (CI) as an an argument that deduces what the voice of conscience must say from it must sound - that is, from the authority that is metaphorically attributed to conscience in the form of a resounding voice. The idea of imagining the CI as the voice of conscience comes from Freud; and the present reconstruction is part of a larger project that aims to reconcile Kant's moral psychology with Freud's theory of moral development. As I reconstruct it, Kant's argument yields an imperative commanding us to act for reasons whose validity we can consistently will to be common knowledge among all agents. Universalizing a maxim thus turns out to consist in willing, not that there be some universally quantified rule of conduct, but rather that a principle of practical reasoning be common knowledge - as a principle of reasoning ought to be
A hybrid approach to finding relevant social media content for complex domain specific information needs

While contemporary semantic search systems offer to improve classical keyword-based search, they are not always adequate for complex domain specific information needs. The domain of prescription drug abuse, for example, requires knowledge of both ontological concepts and "intelligible constructs" not typically modeled in ontologies. These intelligible constructs convey essential information that include notions of intensity, frequency, interval, dosage, and sentiments, which could be important to the holistic needs of the information seeker. In this paper, we present a hybrid approach to domain specific information retrieval (or knowledge-aware search) that integrates ontology-driven query interpretation with synonym-based query expansion, and domain specific rules, to facilitate search. Our framework is based on a context-free grammar (CFG) that defines the query language of constructs interpretable by the search system. The grammar provides two levels of semantic interpretation: (1) a top-level CFG that facilitates retrieval of diverse textual patterns, which belong to broad templates and (2) a low-level CFG that enables interpretation of specific expressions that belong to such patterns. These low-level expressions occur as concepts from four different categories of data: (1) ontological concepts, (2) concepts in lexicons (such as emotions and sentiments), (3) concepts in lexicons with only partial ontology representation, called lexico-ontology concepts (such as side effects and routes of administration (ROA)), and (4) domain specific expressions (such as date, time, interval, frequency, and dosage) derived solely through rules. Our approach is embodied in a novel Semantic Web platform called PREDOSE, which provides search support for complex domain specific information needs in prescription drug abuse epidemiology. When applied to a corpus of over 1 million drug abuse-related web forum posts, our search framework proved effective in retrieving relevant documents when compared with three existing search systems. Complex domain specific search requires richer models to be more effective.Structured knowledge and intelligible constructs together can enhance query interpretation.A hybrid search platform is more effective for practical domain specific information needs.
Symbolic computation of conservation laws for nonlinear partial differential equations in multiple space dimensions

A method for symbolically computing conservation laws of nonlinear partial differential equations (PDEs) in multiple space dimensions is presented in the language of variational calculus and linear algebra. The steps of the method are illustrated using the Zakharov-Kuznetsov and Kadomtsev-Petviashvili equations as examples. The method is algorithmic and has been implemented in Mathematica. The software package, ConservationLawsMD.m, can be used to symbolically compute and test conservation laws for polynomial PDEs that can be written as nonlinear evolution equations. The code ConservationLawsMD.m has been applied to multi-dimensional versions of the Sawada-Kotera, Camassa-Holm, Gardner, and Khokhlov-Zabolotskaya equations.
Detection of the earth with the SETI microwave observing system assumed to be operating out in the Galaxy

This paper estimates the maximum range at which radar signals from the Earth could be detected by a search system similar to the NASA Search for Extraterrestrial Intelligence Microwave Observing Project (SETI MOP) assumed to be operating out in the galaxy. Figures are calculated for the Targeted Search, and for the Sky Survey parts of the MOP, both operating, as currently planned, in the second half of the decade of the 1990s. Only the most powerful terrestrial transmitters are considered, namely, the planetary radar at Arecibo in Puerto Rico, and the ballistic missile early warning systems (BMEWS). In each case the probabilities of detection over the life of the MOP are also calculated. The calculation assumes that we are only in the eavesdropping mode. Transmissions intended to be detected by SETI systems are likely to be much stronger and would of course be found with higher probability to a greater range. Also, it is assumed that the transmitting civilization is at the same level of technological evolution as ours on Earth. This is very improbable. If we were to detect another technological civilization, it would, on statistical grounds, be much older than we are and might well have much more powerful transmitters. Both factors would make detection by the NASA MOP a much more likely outcome.
Interlaminar Effects in Fiber-Reinforced Plastics-A Review

The two-phase nature of a fiber-reinforced polymer gives rise to a multiplicity of possible failure modes [1,2]. The mode of failure depends not only upon the intrinsic fiber and resin properties, ...
An investigation of ethylene hydrogenation catalyzed by metallic molybdenum using an isolatable high-pressure reactor: Identification of the reaction site and the role of carbonaceous deposits

Abstract Ethylene hydrogenation catalyzed by a model Mo(100) single crystal catalyst is investigated using an isolatable high-pressure reactor. The observed reaction kinetics are in agreement with those measured for supported transition metal hydrogenation catalysts showing a zero-order dependence in ethylene and a first-order dependence in hydrogen partial pressures. The reaction activation energy is 8.1 ± 0.5 kcal/mol for a Mo(100) single-crystal model catalyst and for a foil and mass spectral analysis of the products formed following substitution of deuterium for hydrogen shows that a maximum of two deuterium atoms are incorporated into the ethane that is produced. Auger analysis of the surface following reaction reveals the presence of large amounts of carbon (up to ∼7 monolayers). This carbonaceous deposit decomposes on heating the surface to above 1000 K to desorb C1 species. The experimental data suggest that either hydrogen or ethylene can permeate this layer so that hydrogen transfer takes place either at the metal surface or on top of the layer. Blocking the fourfold sites on Mo(100) by oxygen or carbon has only a marginal effect on the overall reaction kinetics, and does not substantially alter the amount of carbon deposited onto the surface during reaction. This result implies that the enhanced catalytic activity observed on metal carbide catalysts is not only due to site blocking, but also arises because of chemical modification of the catalyst by compound formation.
Transport and optical properties of heavily hole doped semiconductors BaCu2Se2 and BaCu2Te2

Experimental and theoretical studies of the electronic and optical properties of orthorhombic BaCu{sub 2}Se{sub 2} and BaCu{sub 2}Te{sub 2} are reported. Experimental data include the electrical resistivity, Hall coefficient, Seebeck coefficient, thermal conductivity, and lattice constants for T {le} 300 K, and optical transmission and diffuse reflectance data at room temperature. Nominally stoichiometric, polycrystalline samples form with hole concentrations inferred from Hall measurements of 2 x 10{sup 18} and 5 x 10{sup 19} cm{sup -3} near room temperature for the selenide and telluride, respectively. The corresponding mobilities are near 15 cm{sup 2} V{sup -1} s{sup -1} for both materials. Optical measurements reveal a transition near 1.8 eV in BaCu{sub 2}Se{sub 2}, while no similar feature was observed for BaCu{sub 2}Te{sub 2}. First principles calculations indicate both materials are direct or nearly direct gap semiconductors with calculated gaps near 1.0 eV and 1.3 eV for the telluride and selenide, respectively, and predict weak absorption below about 2 eV. Transport properties calculated from the electronic structure are also presented.
Flight Simulation Characteristics of the Langley High Reynolds Number Cryogenic Transonic Tunnel

The theory and advantages of the cryogenic tunnel concept are briefly reviewed. The unique ability to vary temperature independently of pressure and Mach number allows, in addition to large reductions in model loads and tunnel power, the independent determination of Reynolds number, Mach number, and aeroelastic effects on the aerodynamic characteristics of the model. Various combinations of Reynolds number and dynamic pressure can be established to accurately represent flight variations of aeroelastic deformation with altitude changes. The consequences of the thermal and caloric imperfections of the test gas under cryogenic conditions have been examined and found to be insignificant for operating pressures up to 5 atm. The characteristics of the Langley 34 cm (13.5 in.) Pilot Cryogenic Transonic Pressure Tunnel are described and the results of initial tunnel operation are presented. Tests of a two-dimensional airfoil at a Mach number of 0.85 show identical pressure distributions for a chord Reynolds number of 8.6 X 106 obtained first at a stagnation pressure of 4.91 atm at a stagnation temperature of +120°F and then at a stagnation pressure of 1.19 atm at a stagnation temperature of -250°F.
Asymptotics and Dimensional Dependence of the Number of Critical Points of Random Holomorphic Sections

We prove two conjectures from [DSZ2,DSZ3] concerning the expected number of critical points of random holomorphic sections of a positive line bundle. We show that, on average, the critical points of minimal Morse index are the most plentiful for holomorphic sections of \({\mathcal {O}(N) \to \mathbb {CP}^m}\) and, in an asymptotic sense, for those of line bundles over general Kahler manifolds. We calculate the expected number of these critical points for the respective cases and use these to obtain growth rates and asymptotic bounds for the total expected number of critical points in these cases. This line of research was motivated by landscape problems in string theory and spin glasses.
Distributions of Fourier modes of cosmological density fields.

We discuss the probability distributions of Fourier modes of cosmological density fields using the central limit theorem is it applies to weighted integrals of random fields. It is shown that if the cosmological principle holds in a certain sense, i.e., the Universe approaches homogeneity and isotropy sufficiently rapidly on very large scales, the one-point distribution of each Fourier mode of the density field is Gaussian whether or not the density field itself is Gaussian. Therefore, one-point distributions of the power spectrum obtained from observational data or from simulations are not a good test of whether the density field is Gaussian.
Modelling macroscopic imperfections for the prediction of flow localization and fracture

Ductile materials subjected to plastic deformation experience the different stages of void nucleation, growth and coalescence that eventually lead to ductile fracture. Several models have been proposed to assess the influence of this damage on flow localization and fracture. In general, the plastic behaviour is represented by a constitutive model for porous or damaged materials. It is typical to introduce a material imperfection, with porosity higher than average, which evolves up to localization and fracture. However, the void volume fraction in the imperfection is chosen more or less arbitrarily. In the present ivfirk, a model that evaluates this void volume fraction more rigorously is developed. The forming limit diagram (FLD) for a dual phase-steel is calculated using the damage-based imperfection calculation and validated with experimental results. The effect of void shape on the imperfection porosity level and limit strains in sheet forming is also assessed with the present method.
[Ne V] Imaging of N49 in the Large Magellanic Cloud

We present subarcsecond imaging in [Ne V] of N49, the brightest optical SNR in the LMC. Between the "cool" optical and "hot" X-ray regimes, [Ne V] emission indicates intermediate temperatures for collisionally excited plasmas (2-6 × 105 K), for which imaging has been extremely limited. We compare the flux in these images to the O VI measured spectroscopically by FUSE in individual apertures and find dereddened line ratios that are reasonably consistent with our predictions for intermediate velocity shocks. The overall luminosity in [Ne V] for the entire remnant is 1.2 × 1036 ergs s-1, which, given the measured line ratios, implies an overall O VI luminosity of 1.5 × 1038 ergs s-1. These large radiative losses indicate that this material must have been shocked recently relative to the total lifetime of the remnant. We also explore the complex spatial structure. We find [Ne V] tracing the [O III] emission more closely than it does Hα, measure significant shifts (~0.1 pc) between the peaks of different emission lines, and find 2 orders of magnitude variations in the flux ratios for different filaments across the remnant. These properties, as well as the general filamentary character of the optical emission, suggest thermally unstable intermediate-velocity shocks.
Linking Riveting Process Parameters to the Fatigue Performance of Riveted Aircraft Structures

The onset of widespread fatigue damage in riveted aircraft structure has been linked to sharp gradients of stress arising from contact between rivets and rivet holes. In addition, the mechanics of load transfer in lap joint structure (and resulting damage) is influenced by the through-thickness restraint offered by the installed rivet. Finally, the propagation of fatigue cracks at and around the rivet/hole interface is tied to the residual stress field induced during the riveting process. In light of the influence that rivet installation has on the fatigue performance of riveted joints, the aim was to link details of a quasi-static, squeeze force-controlled riveting process as provided by finite element modeling to the resulting residual stress field in a single-lap joint structure. Supporting experiments provide insight into the inelastic response of the rivet material and validation of the model results. These results from the model reveal both a strong through-thickness gradient in residual stresses and a change in the distribution of residual hoop stress near the rivet/hole interface with squeeze force. Comments are also made regarding the relationship between riveting process parameters and trends in observed fatigue failures of riveted lap joint test articles.
Acceleration-induced nonlocality: uniqueness of the kernel

Abstract We consider the problem of uniqueness of the kernel in the nonlocal theory of accelerated observers. In a recent work [Ann. Phys. (Leipzig) 11 (2002) 309], we showed that the convolution kernel is ruled out as it can lead to divergences for nonuniform accelerated motion. Here we determine the general form of bounded continuous kernels and use observational data regarding spin-rotation coupling to argue that the kinetic kernel given by K ( τ , τ ′)= k ( τ ′) is the only physically acceptable solution.
Spatial Discretization of Axially Moving Media Vibration Problems

Spatial discretization of axially moving media eigenvalue problems is examined from the perspectives of moving versus stationary system basis functions, configuration space versus state space form discretization, and subcritical versus supercritical speed conver-. gence. The moving string eigenfunctions, which have previously been shown to give excellent discretization convergence under certain conditions, become linearly dependent and cause numerical problems as the number of terms increases. This problem does not occur in a discretization of the state space form of the eigenvalue problem, although convergence is slower, not monotonic, and not necessarily from above. Use of the moving string basis at supercritical speeds yields strikingly poor results with either the configuration or state space discretizations. The stationary system eigenfunctions provide reliable eigenvalue predictions across the range of problems examined. Because they have known exact solutions, the moving string on elastic foundation and the traveling, tensioned beam are used as illustrative examples. Many of the findings, however, apply to more complex moving media problems, including nontrivial equilibria of nonlinear models.
Rh-catalyzed enantioselective hydrogenation of vinyl boronates for the construction of secondary boronic esters

Rh-catalyzed hydrogenation of prochiral vinyl boronates occurs in an enantioselective fashion in the presence of the chiral ligand Walphos 1. This transformation provides access to chiral secondary organoboronates that are not available from alkene hydroboration reactions. The chiral reaction products should be useful in organic synthesis, and preliminary experiments suggest that they may participate in one-pot amination and homologation reactions.