cssi/SciSciGPT-SciSciNet huggingface dataset:
Mixed convection in a wall plume

Abstract The mixed convection flow that arises due to a finite heated element located on a vertical adiabatic surface in an external flow, aligned with the surface, is studied analytically. The problem is of particular interest in electronic circuitry cooling and in heat removal in various manufacturing systems. The boundary layer flow is studied to determine the heat transfer from the heated element, the temperature decay downstream and the flow field that results. Numerical results are obtained, employing finite difference methods for a wide range of the mixed convection parameter. The pure natural convection problem is studied first and the results obtained are compared with earlier studies on wall plumes. The effect of mixed convection on the heat transfer and fluid flow characteristics is studied in detail. The temperature at the heated element surface is studied as a function of the mixed convection parameter. The effect of the inclusion of radiative loss on the temperature and flow fields is also examined.
Brucine N-oxide-catalyzed Morita–Baylis–Hillman reaction of vinyl ketones: a mechanistic implication of dual catalyst system with proline

The brucine N-oxide promoted Morita–Baylis–Hillman (MBH) reaction of vinyl ketones with aldehydes has been achieved. The corresponding asymmetric version of MBH reaction was also investigated, and the electron-deficient aryl aldehydes have emerged as suitable reaction partners for vinyl ketones; where proline was employed as a co-catalyst. In this dual catalyst system, proline is believed to form iminium intermediates with electron-deficient aryl aldehydes, while the N-oxide activates vinyl ketones to provide enolates through conjugate addition. Upon the combination of these two intermediates, the MBH products with high enantioselectivities are obtained by controlling of the rate-determining step through H-bridged chair-like transition state. Intrinsically, the resulting MBH products, alcohols, are found to interfere with the formation of both intermediates, enolates and proline iminium intermediates, thus the observed enantioselectivity of products attenuates upon further reaction conversion, possibly due to autocatalysis. This current study sheds lights on the synthetic utility of iminium species, derived from electron-deficient aryl aldehydes and proline.
Evaluation of tributylgermanium hydride as a reagent for the reductive alkylation of active olefins with alkyl halides

Abstract The reductive alkylation of acrylonitrile and of 2-cyclohexen-1-one by alkyl halides using tributylgermanium hydride was systematically evaluated. The performance of the germanium reagent was compared to that of the more commonly employed tributyltin hydride. For certain applications the germanium reagent afforded improved yields without the use of large excess olefin concentrations. Disadvantages of the germanium reagent include a tendency to hydrogermylate active terminal olefins and a general low reactivity towards alkyl halide substrates. The following series of six other triorganotin and triorganogermanium hydrides were also briefly screened for possible application to reductive alkylations: trimesityltin hydride, trimesitylgermanium hydride, triphenyltin hydride, triphenylgermanium hydride, trineopentyltin hydride, and tricyclohexylgermanium hydride.
Infantile Kawasaki disease and peripheral gangrene

We report a 1-month-old infant with Kawasaki disease and peripheral gangrene. We advocate using the newly published American Heart Association guidelines advising early laboratory and echocardiogram investigations in infants with fever but without other classic manifestations of Kawasaki disease. Initiation of early therapy may prevent this serious complication with its permanent sequelae.
Breast cancer, dermatofibromas and arsenic.

Abstract #4160 Background: Dermatofibromas are common benign tumors in women and breast cancer is the most common malignancy in women and an environmental etiology has been suspected in both conditions. The aim of this study is to determine if there is any relationship between the two conditions. Materials and Methods: 5 patients with dermatofibromas and 10 control patients(2 groups) had blood arsenic levels and their skin biopsies measured for arsenic by inductively coupled mass spectometry. Fifty randomly selected patients with breast cancer and 50 control patients were examined for the presence of dermatofibromas. Results: The patients with dermatofibromas had no detectable blood arsenic but the dermatofibromas were found to have an arsenic concentration of .171 micrograms/gram. One control group(5 patients) with no detectable blood arsenic had a skin concentration of .07 micrograms/gram and the other control group (5 patients) with an average blood concentration of 6 micrograms/liter had a concentration in their skin of .06 micrograms/gram. 43/50 patients with breast cancer had dermatofibromas and 32/50 had multiple dermatofibromas, compared with 10/50 control patients with dermatofibromas and only 1/50 with multiple dermatofibromas. In all breast cancer patients, the dermatofibromas preceded the breast cancer by many years though none of the patients could give an exact answer to that question. Conclusions: Dermatofibromas may represent a reservoir for arsenic and may interfere with the rapid excretion of arsenic resulting in prolonged exposure. Arsenic may be important to the development of dermatofibromas as shown by the proliferation of endothelial cells, the main target of arsenic toxicity, and the increased melanin and hemosiderin, the classic causes of hyperpigmentation in chronic arsenic toxicity.Dermatofibromas represent a sign of chronic arsenic exposure, a powerful environmental carcinogen, 5-20 years prior to the clinical signs of breast cancer, when the changes in the cells would first be developing. This is the first time that any link to an environmental carcinogen has been shown in breast cancer and may represent an important venue to dramatically decrease the number of cases in the future. The dermatofibroma, especially multiple dermatofibromas, represent an important cutaneous sign of women at risk for breast cancer. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4160.
Neuroimaging Biomarkers of Neurodegenerative Diseases and Dementia

Neurodegenerative disorders leading to dementia are common diseases that affect many older and some young adults. Neuroimaging methods are important tools for assessing and monitoring pathological brain changes associated with progressive neurodegenerative conditions. In this review, the authors describe key findings from neuroimaging studies (magnetic resonance imaging and radionucleotide imaging) in neurodegenerative disorders, including Alzheimer's disease (AD) and prodromal stages, familial and atypical AD syndromes, frontotemporal dementia, amyotrophic lateral sclerosis with and without dementia, Parkinson's disease with and without dementia, dementia with Lewy bodies, Huntington's disease, multiple sclerosis, HIV-associated neurocognitive disorder, and prion protein associated diseases (i.e., Creutzfeldt-Jakob disease). The authors focus on neuroimaging findings of in vivo pathology in these disorders, as well as the potential for neuroimaging to provide useful information for differential diagnosis of neurodegenerative disorders.
Theoretical Uncertainties in Red Giant Branch Evolution: The Red Giant Branch Bump

A Monte Carlo simulation exploring uncertainties in standard stellar evolution theory on the red giant branch of metal-poor globular clusters has been conducted. Confidence limits are derived on the absolute V-band magnitude of the bump in the red giant branch luminosity function (MV,b) and the excess number of stars in the bump, Rb. The analysis takes into account uncertainties in the primordial helium abundance, abundance of ?-capture elements, radiative and conductive opacities, nuclear reaction rates, neutrino energy losses, the treatments of diffusion and convection, the surface boundary conditions, and color transformations. The uncertainty in theoretical values for the red giant bump magnitude varies with metallicity between +0.13 and -0.12 mag at [Fe/H] = -2.4 and between +0.23 and -0.21 mag at [Fe/H] = -1.0. The dominant sources of uncertainty are the abundance of the ?-capture elements , the mixing length, and the low-temperature opacities. The theoretical values of MV,b are in good agreement with observations. The uncertainty in the theoretical value of Rb is ?0.01 at all metallicities studied. The dominant sources of uncertainty are the abundance of the ?-capture elements, the mixing length, and the high-temperature opacities. The median value of Rb varies from 0.44 at [Fe/H] = -2.4 to 0.50 at [Fe/H] = -1.0. These theoretical values for Rb are in agreement with observations.
Spin-orbit interaction from Matrix Theory

Abstract We study the leading order spin dependence of graviton scattering in eleven dimensions, and show that the results obtained from supergravity and from Matrix Theory precisely agree.
Functional ontogeny of human lymphoid cells as a factor in maternal-fetal tolerance.

: The development of immunocompetence during gestation depends upon the sequential differentiation of antigen-specific lymphoid cells in the context of epithelial inducing microenvironments. These early intrauterine events, which appear to be antigen-independent, include clonal diversification of idiotypes and isotypes as well as commitment to B or T cell lineages. The steps in cellular maturation can be traced through the use of lymphocyte differentiation markers. Cooperation among lymphoid subsets, as well as from nonlymphoid cells and possibly other cofactors, is necessary for the effective function of this array of lymphocytes. The rate of expansion of functional immunity may be limited as much by the ontogeny of these collaborating influences as by the intrinsic immaturity of the B and T cells themselves.
Arithmeticity of complex hyperbolic triangle groups

Complex hyperbolic triangle groups, originally studied by Mostow in building the rst nonarithmetic lattices in PU(2 ; 1), are a natural generalization of the classical triangle groups. A theorem of Takeuchi states that there are only nitely many Fuchsian triangle groups that determine an arithmetic lattice in PSL2(R), so triangle groups are generically nonarithmetic. We prove similar niteness theorems for complex hyperbolic triangle groups that determine an arithmetic lattice in PU(2; 1).
Bispectral reconstruction of signals in noise: amplitude reconstruction issues

Two solutions to the problem of recovering deterministic signals (objects) from the bispectrum of noisy observations of the signal are proposed. Some of the tradeoffs involved in using bispectrum-based reconstruction approaches vis-a-vis other techniques are discussed. Applications to several types of problems are discussed. Four simulation examples are given. >
Finding the right path: Baldwin “Rules for Ring Closure” and stereoelectronic control of cyclizations

Truly important scientific breakthroughs often come from catching the glimpses of order in chaos and distilling a large body of disjointed data into a clear set of simple concepts. Even more impressive is when the new conceptual framework is created with some of the keystones still missing. Such bold predictions, i.e. Mendeleev's eka-silicon, challenge and inspire, serving as powerful catalysts for scientific growth. The rules for ring closure formulated by Sir Jack Baldwin in 1976 constitute one of such bold intellectual advances. Baldwin developed a classification system that brought order to the chaos of possible cyclization patterns and suggested a set of rules to define the favourable modes of ring closure. Where sufficient data was lacking, particularly for the cyclizations of alkynes, Baldwin made testable predictions that challenged theoretical and experimental chemists. These guidelines have become the common starting point in the design of new cyclization reactions and catalyzed the development of modern stereoelectronic concepts.
Synthesis of spiro-fused (C5)-isoxazolino-(C4)-pyrazolones (1-oxa-2,7,8-triazaspiro[4,4]-2,8-dien-6-ones) via 1,3-dipolar cycloaddition and cycloelimination.

An efficient and selective method for the synthesis of spiro-fused (C5)-isoxazolino-(C4)-pyrazolones (C) is reported. The process consists of utilizing the Baylis−Hillman reactionor a quicker, stepwise MAC procedureto give I followed by 1,3-dipolar cycloaddition and Swern oxidation to give β-ketoesters H, which were condensed with hydrazine derivatives to provide hydrazones that underwent cycloelimination. These novel spiro-fused (C5)-isoxazolino-(C4)-pyrazolones were confirmed by spectroscopic analysis as well as single-crystal X-ray of 5. We also concluded that all condensations/cycloeliminations, except with hydrazine itself, were more effective with catalysts or higher reaction temperatures. For example, TiCl4 was an efficient catalyst for hydrazone formation and cycloelimination with methylhydrazine, while phenyl-, benzyl-, and (4-methoxyphenyl)hydrazine reacted effectively without catalyst in refluxing xylene.
A Stochastic Perturbation of Inviscid Flows

We prove existence and regularity of the stochastic flows used in the stochastic Lagrangian formulation of the incompressible Navier-Stokes equations (with periodic boundary conditions), and consequently obtain a Ck,α local existence result for the Navier-Stokes equations. Our estimates are independent of viscosity, allowing us to consider the inviscid limit. We show that as ν → 0, solutions of the stochastic Lagrangian formulation (with periodic boundary conditions) converge to solutions of the Euler equations at the rate of \(O(\sqrt{\nu t})\).
Early Introduction of Solid Foods among Urban African-American Participants in WIC

Abstract Objective To compare infant feeding practices among low-income, urban, African-American women enrolled in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) with current recommendations for infant feeding. Design Longitudinal follow-up of women and their infants who participated in a WIC-based breast-feeding promotion project. Women enrolled prenatally at or before 24 weeks of gestation were followed up until 16 weeks postpartum. Subjects/setting Two hundred seventeen African-American WIC participants in an urban area. Methods Data related to infant feeding practices were collected by interviewers who used a structured questionnaire to determine when nonmilk liquids or solids were introduced to the infant. Reported practices were compared with current recommendations. Statistical analysis performed Contingency table analysis, including χ 2 tests, and multivariate analysis using logistic regression. Results By 7 to 10 days postpartum, approximately a third of infants were receiving some nonmilk liquids or solids; this escalated to 77% by 8 weeks and 93% by 16 weeks postpartum. Women breast-feeding exclusively (ie, not adding nonmilk liquids or solids) were least likely, and women providing mixed feeding (breast milk and formula) were more likely, than women feeding formula exclusively to introduce nonmilk liquids and solids at each data collection time period. Applications/conclusions WIC participants who receive instruction about infant feeding nutrition are no more likely than mothers who do not participate in WIC to follow infant feeding guidelines recommended by the American Academy of Pediatrics in regard to the time when solids should be introduced to infants' diet. Our findings suggest the need for WIC to implement more powerful and innovative educational and motivational strategies to help mothers delay the introduction of nonmilk liquids and solid foods until their infants are 4 to 6 months old, as recommended. J Am Diet Assoc. 1999;99:457–461.
Evolution of Subsea Production Systems: A Worldwide Overview

The evolution in the use of subsea technology has seen advancement from one well in the Gulf of Mexico in 1961 to more than 750 wells in a wide variety of locations by the end of 1993. Along with the growth in numbers, the industry has seen rapid advances in technology, increased distances from the host facility, and water depth records. This paper gives an overview of the evolutionary changes in subsea applications, with emphasis on the most active regions and on some of the milestone installations that shaped the technology advance.
Surveillance in the Digital Enclosure

Popular portrayals of ubiquitous computing downplay the surveillance implications of emerging forms of networked interactivity. This essay supplements such accounts by analyzing interactive spaces as digital enclosures which restrict access to the means of interaction to those who “freely” submit to the detailed forms of monitoring that take place within them. It supplements privacy-based critiques of surveillance with questions about the ownership and control of such data and the implications of this control for networked communication.
Cluster-subcluster Mergers and the Formation of Narrow-angle Tailed Radio Sources

ABSTRA C T We examine the ROSAT PSPC X-ray properties of a sample of 15 Abell clusters containing 23 narrow-angle tailed (NAT) radio galaxies. We find that clusters with NATs show a significantly higher level of substructure than a similar sample of radio-quiet clusters, indicating that NAT radio sources are preferentially located in dynamically complex systems. Also, the velocity distribution of the NAT galaxies is similar to that of other cluster members; these velocities are inadequate for producing the ram pressure necessary to bend the radio jets. We therefore propose a new model for NAT formation, in which NATs are associated with dynamically complex clusters undergoing merger events. The U-shaped NAT morphology is produced in part by the merger-induced bulk motion of the ICM bending the jets.
The chemistry of marine furanocembranoids, pseudopteranes, gersolanes, and related natural products

Covering: up to the middle of 2007 An overview of the chemistry and biology of the diterpene natural products known as the furanocembranoids, pseudopteranes, and gersolanes is provided; 85 references are cited.
Experience with laser safety in the USA-a review

Following several research programs in the 1960's aimed at studying the adverse biological effects of lasers and other optical radiation sources, laser occupational exposure limits were set and general safety standards were developed. Today, the experience from laser accidents and the development of new lasers and new applications have altered the format of the exposure limits and the safety procedures. It is critically important to distinguish between different biological injury mechanisms. The biological effects of ultraviolet radiation upon the skin and eye are additive over a period of at least one workday, and require different safety procedures. The scattered UV irradiance from excimer lasers may be quite hazardous, depending upon wavelength and action spectra. Since laser technology is young, the exposure of an individual in natural sunlight must be studied to evaluate the potential for chronic effects. The safety measures necessary in the use of lasers depend upon a hazard evaluation. The appropriate control measures and alternate means of enclosure, baffling, and operational control measures are presented. Present laser safety standards are explained briefly. Eye protective techniques and eyewear are considered for a variety of sources. The optical properties of enclosure materials are also discussed.
Catalytic asymmetric addition of diethylzinc to aldehydes via chiral, non-racemic β-hydroxy and β-methoxy salicylhydrazone catalysts

Abstract (1S,2S)-Pseudoephedrine and (1S,2S)-pseudonorephedrine have been converted to their corresponding hydrazines and condensed with either o-salicylaldehyde or 2-hydroxy-1-naphthaldehyde to afford a series of β-hydroxysalicylhydrazones that have been employed in the asymmetric addition of diethylzinc to 2-naphthaldehyde in up to 56% ee. In addition to this, the Ephedra hydrazines were also condensed with the o-hydroxyacetophenone derivative to form related hydrazones. The use of these corresponding hydrazones in the asymmetric addition reaction with the diethylzinc did not yield improved enantioselectivities. Finally, Enders’ hydrazine was used as a chiral scaffold for the synthesis of β-methoxysalicylhydrazones. These compounds were employed in the asymmetric addition of diethylzinc to a variety of aromatic aldehydes with enantiomeric excesses as high as 68% ee.
Overlapping community detection in networks: The state-of-the-art and comparative study

This article reviews the state-of-the-art in overlapping community detection algorithms, quality measures, and benchmarks. A thorough comparison of different algorithms (a total of fourteen) is provided. In addition to community-level evaluation, we propose a framework for evaluating algorithms' ability to detect overlapping nodes, which helps to assess overdetection and underdetection. After considering community-level detection performance measured by normalized mutual information, the Omega index, and node-level detection performance measured by F-score, we reached the following conclusions. For low overlapping density networks, SLPA, OSLOM, Game, and COPRA offer better performance than the other tested algorithms. For networks with high overlapping density and high overlapping diversity, both SLPA and Game provide relatively stable performance. However, test results also suggest that the detection in such networks is still not yet fully resolved. A common feature observed by various algorithms in real-world networks is the relatively small fraction of overlapping nodes (typically less than 30p), each of which belongs to only 2 or 3 communities.
On the viscosity solutions to a degenerate parabolic differential equation

In this work, we study positive viscosity solutions of the doubly nonlinear degenerate parabolic equation $$\varDelta _\infty \phi =(\phi ^3)_t=3\phi ^2\phi _t$$ in $$\varOmega \times (0,T)$$ , where $$\varOmega \subset {\mathbb {R}}^n$$ is a bounded domain. Here, $$\varDelta _\infty $$ is the infinity Laplacian. We prove a comparison principle, existence of continuous positive solutions, and some results regarding long-time asymptotic behavior. A maximum principle for $${\mathbb {R}}^n\times (0,T)$$ is also proven here. We adapt ideas and techniques described in Crandall and Ishii (Differ Integral Equ 3(6):1001–1014, 1990) and Crandall et al. (Bull Am Math Soc 27:1–67, 1992).
The residential space heating problem in Lithuania

Abstract Several important problems are associated with heating of housing in Lithuania. Residential heating is heavily dependent on fossil fuel, combustion of which contributes to air pollution and atmospheric build-up of carbon dioxide. Subsidies from the State budget to maintain the residential heat price at a below-cost level declined in recent years, but are often still substantial. Eliminating subsidies for heat is politically difficult. Many households face difficulty in paying their heating bill, which has risen greatly in real terms in the past five years. The problem is amplified since most households in apartments are billed on the basis of their floor area, not on real heat consumption. The magnitude of the above problems is heightened by the inefficient manner in which energy is used to heat most residential buildings. This inefficiency concerns losses in transmission and distribution of district heat, high losses through the building envelopes, as well as lack of proper metering and control of district heat. imrpoving the energy efficiency of heating is recognized as an important goal for addressing the problems outlined above. This report describes housing and space heating in Lithuania. It discusses the process of privatization and how it affects heating energy use, as well as implementation of conservation measures and retrofitting. It also discusses some of the measures undertaken by both property owners and by governmental agencies that affect heating energy use. The report summarizes results from a number of recent studies of the potential for energy savings in heating Lithuanian multifamily buildings. We discuss barriers to realization of the potential, and institutional and financial approaches for overcoming them. In closing we recommend actions that should be taken soon to move Lithuanian housing along a path to greater energy efficiency.
The influence of antenna configuration and standing wave effects on density profile in a large-area inductive plasma source

The electrical and plasma properties of a large-area inductive plasma source are investigated. The source is a 71 cm × 61 cm × 20 cm metal chamber providing a processing area of 37 cm × 47 cm for large-size wafers and glass substrates for flat panel displays. The exciting antenna is embedded inside the processing chamber, and the rf power is inductively coupled from the antenna to the plasma through thin (1.7 mm thick) quartz tubes. A tuning network is used to launch a travelling wave or a wave with a desired standing-wave ratio. The antenna-plasma system is modelled as a lossy transmission line, and a transformer model is applied to study the electrical properties of the system. The model is used to evaluate the conditions required to launch a travelling wave, and these conditions are verified experimentally. The plasma density distributions under various operating conditions are measured with Langmuir probes and compared to a global model for inductive discharges. Our experiments show that high plasma densities are produced over a large area, and that the density profiles are strongly influenced by the antenna configuration and standing-wave effects.
Calcium Ion Gradients Modulate the Zinc Affinity and Antibacterial Activity of Human Calprotectin

Calprotectin (CP) is an antimicrobial protein produced and released by neutrophils that inhibits the growth of pathogenic microorganisms by sequestering essential metal nutrients in the extracellular space. In this work, spectroscopic and thermodynamic metal-binding studies are presented to delineate the zinc-binding properties of CP. Unique optical absorption and EPR spectroscopic signatures for the interfacial His(3)Asp and His(4) sites of human calprotectin are identified by using Co(II) as a spectroscopic probe. Zinc competition titrations employing chromophoric Zn(II) indicators provide a 2:1 Zn(II):CP stoichiometry, confirm that the His(3)Asp and His(4) sites of CP coordinate Zn(II), and reveal that the Zn(II) affinity of both sites is calcium-dependent. The calcium-insensitive Zn(II) competitor ZP4 affords dissociation constants of K(d1) = 133 ± 58 pM and K(d2) = 185 ± 219 nM for CP in the absence of Ca(II). These values decrease to K(d1) ≤ 10 pM and K(d2) ≤ 240 pM in the presence of excess Ca(II). The K(d1) and K(d2) values are assigned to the His(3)Asp and His(4) sites, respectively. In vitro antibacterial activity assays indicate that the metal-binding sites and Ca(II)-replete conditions are required for CP to inhibit the growth of both Gram-negative and -positive bacteria. Taken together, these data provide a working model whereby calprotectin responds to physiological Ca(II) gradients to become a potent Zn(II) chelator in the extracellular space.
Sway Reduction on Container Cranes Using Delayed Feedback Controller

Traditionally, container cranes are modeled as a simple pendulum, witheither a flexible or a rigid hoisting cable, and a lumped mass at theend of that cable. In the case of large container cranes, the actualconfiguration of the hoisting mechanism is significantly different. Itconsists typically of an arrangement of four hoisting cables, which arehoisted from four different points on the trolley and attached on theload side to four points on a spreader bar used to lift containers.Thus, the dynamics of the actual container-crane hoisting assembly isdifferent from that of a simple pendulum. A controller design based onthe actual model is more likely to result in an improved response. Inthis work, a mathematical model of the actual container crane isdeveloped. Then, a simplified version of this model is used to calculatethe gain and delay for the delay controller developed earlier. Numericalsimulations are performed by applying the delay controller to the fullnonlinear model of the container crane.
Strange) meson interferometry at RHIC

The authors make predictions for the kaon interferometry measurements in Au + Au collisions at the relativistic Heavy Ion Collider (RHIC). A first order phase transition from a thermalized Quark-Gluon-Plasma (QGP) to a gas of hadrons is assumed for the transport calculations. The fraction of kaons that are directly emitted from the phase boundary is considerably enhanced at large transverse momenta K{sub T} {approx} 1 GeV/c. In this kinematic region, the sensitivity of the R{sub out}/R{sub side} ratio to the QGP-properties is enlarged. The results of the 1-dimensional correlation analysis are presented. The extracted interferometry radii, depending on K{sub T}, are not unusually large and are strongly affected by finite momentum resolution effects.
The interaction of fluoride ion with organosilicons: facile isomerizations and new reactions of silicon hydrides

Abstract Cesium fluoride isomerization of several derivatives of 3-silabicyclo[3.2.1]octane and 2-silabicyclo[2.2.1]heptane as well as chiral α-NpPhMeSiH are described. The effect of solvent, 18-crown-6 ether, and other salts is discussed. Associated side reactions prompted study of the conversion of Ph3SiH to Ph3SiF by CsF and the identification of the products formed from the reaction of Ph3SiH with DMF, N-methylformanilide, and benzamide in the presence of metal fluorides.
A Highly Efficient Synthesis of Rocaglaols by a Novel α‐Arylation of Ketones

Rocaglaols are natural products exhibiting a range of biological activities. A new synthetic method for the α-arylation of ketones allows for the synthesis of previously inaccessible rocaglaol derivatives. The key sequence consists of a previously unreported Suzuki type reaction using brominated silyl enol ethers as substrates followed by deprotection of the arylated silyl enol ethers. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Branes from matrices

Abstract Various aspects of branes in the recently proposed matrix model for M-theory are discussed. A careful analysis of the supersymmetry algebra of the matrix model uncovers some central changes which can be activated only in the large N limit. We identify the states with non-zero charges as branes of different dimensions.
A case study in model reduction of linear time-varying systems

In this paper, the balanced truncation procedure is applied to time-varying linear systems, both in continuous and in discrete time. The methods are applied to a linear approximation of a diesel exhaust catalyst model. The reduced-order systems are obtained by using certain projections instead of direct balancing. An approximate zero-order-hold discretization of continuous-time systems is described, and a new a priori approximation error bound for balanced truncation in the discrete-time case is obtained. The case study shows that there are several advantages to work in discrete time. It gives simpler implementation with fewer computations.
Sensing capacity for Markov random fields

This paper computes the sensing capacity of a sensor network, with sensors of limited range, sensing a two-dimensional Markov random field, by modeling the sensing operation as an encoder. Sensor observations are dependent across sensors, and the sensor network output across different states of the environment is neither identically nor independently distributed. Using a random coding argument, based on the theory of types, we prove a lower bound on the sensing capacity of the network, which characterizes the ability of the sensor network to distinguish among environments with Markov structure, to within a desired accuracy
Transforming partner relationships through technological innovation

Purpose – To develop and propose a conceptual model that explains why downstream channel members (e.g. retailers) are likely to adopt or resist the implementation of emerging partner relationship management (PRM) technologies by their channel counterparts (i.e. suppliers).Design/methodology/approach – The conceptual model is grounded in organizational innovation theory and utilizes select case examples to support posited relationships.Findings – Resellers' level of commitment to new PRM tools deployed by suppliers is likely to be driven by their perception of the technology's impact on the equity (i.e. fairness) and efficiency (i.e. cost) of existing channel relationships. In turn, resellers' perceptions about the equity and efficiency implications of PRM technology adoption are expected to be influenced by several factors, including: environmental factors, suppliers' choice of influence strategies and the characteristics of the exchange relationship.Research limitations/implications – Aside from offering...
X-Ray Emission of Gamma-Ray Bursts

X-ray emission can provide a crucial diagnostic of gamma-ray bursts (GRBs). We calculate the X-ray and gamma-ray spectra of impulsive acceleration episodes related to GRB pulses. We use the synchrotron shock model (SSM) as a basis of our calculations. We show that the current data on soft-to-hard emission ratios of GRB pulse emission are in agreement with the SSM. In particular, GRB averaged pulse emission detected by Ginga is in agreement with the SSM low-energy spectra. We deduce that Ginga detected the majority of bright GRBs detectable by BATSE. These results indicate that the physical environment surrounding the GRB emission site is optically thin to X-ray photon energies for a large fraction of burst duration. We also calculate emission ratios in the Einstein, ROSAT, Satellite per Astronomia raggi X (SAX), and HETE energy bands, and discuss how future information on simultaneous soft/hard GRB emission can contribute to distinguishing different emission models. Two different components of X-ray emission may simultaneously exist in a fraction of GRBs. One component is clearly associated with the individual GRB pulses, and an additional component may be related to the pulse X-ray spectral upturns and/or the precursors/tails occasionally observed. We also show that a meaningful search of GRB-driven X-ray flashes in Andromeda (M31) can be carried out with existing ROSAT PSPC data and future SAX WFC observations.
The Relative Intensities of Positive Rays from the Isotopes of Lithium

The relative intensities of positive rays from the isotopes of lithium were investigated for various lithium compounds at different temperatures, using Dempster's method of positive ray analysis. It was found that there is in general a change in the ratio ${\mathrm{Li}}_{7}$/${\mathrm{Li}}_{6}$ with temperature, the ratio decreasing at higher temperatures and increasing at lower. An application of Richardson's law shows that the two isotopes have different work functions, ${\mathrm{Li}}_{6}$ having a greater work function than ${\mathrm{Li}}_{7}$. The ratio $\frac{{b}_{6}}{{b}_{7}}$ is constant over wide ranges of temperature for a given lithium compound, but is different for different compounds.
N3logic: A logical framework for the world wide web

The Semantic Web drives toward the use of the Web for interacting with logically interconnected data. Through knowledge models such as Resource Description Framework (RDF), the Semantic Web provides a unifying representation of richly structured data. Adding logic to the Web implies the use of rules to make inferences, choose courses of action, and answer questions. This logic must be powerful enough to describe complex properties of objects but not so powerful that agents can be tricked by being asked to consider a paradox. The Web has several characteristics that can lead to problems when existing logics are used, in particular, the inconsistencies that inevitably arise due to the openness of the Web, where anyone can assert anything. N3Logic is a logic that allows rules to be expressed in a Web environment. It extends RDF with syntax for nested graphs and quantified variables and with predicates for implication and accessing resources on the Web, and functions including cryptographic, string, math. The main goal of N3Logic is to be a minimal extension to the RDF data model such that the same language can be used for logic and data. In this paper, we describe N3Logic and illustrate through examples why it is an appropriate logic for the Web.
Highly Efficient Chemoenzymatic Synthesis of α-Galactosyl Epitopes with a Recombinant α(1→3)-Galactosyltransferase

α-Galactosyl epitopes are carbohydrate structures bearing a Galα1-3Galβ terminus. The interaction of these epitopes on the surface of animal cells with anti-α-galactosyl antibodies in human serum is believed to be the main cause in antibody-mediated hyperacute rejection in xenotransplantation. This report describes an efficient chemoenzymatic approach based on the use of recombinant α(1→3)-galactosyltransferase (α1,3-GalT) for the synthesis of xenoactive α-galactosyl epitopes, which are highly desired in the research of xenotransplantation and immunotherapy. A truncated bovine α1,3-GalT (80−368) was cloned into the pET15b vector and subsequently transformed into E. coli BL21 strain. This expression system efficiently produced the soluble recombinant enzyme on a large scale with highly specific activity. A variety of α(1→3)-galactosylated epitopes were synthesized using such a recombinant enzyme. In a unique fashion, α-galactosyl pentasaccharide was synthesized via a one-pot, two-step enzymatic synthesis w...
A theory of scattering by nonisotropic irregularities with application to radar reflections from the aurora

Abstract A model of the distribution of ionization in an aurora is developed that can explain the aspect sensitivity of radar echoes obtained at VHF during auroral activity. Even when the radar is in the midst of a zone of auroral activity, echoes are obtained only from low angles of elevation in roughly the northern quadrant. However, both the horizontal and vertical angles over which echoes are obtained increase significantly as frequency is decreased from 100 to 25 Mc/s. These observations can be explained in terms of columns of ionization parallel to the earth's magnetic field. The size of the columns must, however, be much smaller than suggested by Chapman (1952) or by Booker , Gartlein , and Nichols (1955). The column size required is of the order of 40 in in length and 1 m in diameter, smoothed so as to avoid discontinuities at the surfaces. It is quite doubtful whether the formation of such short columns of ionization can be associated directly with the formation of visual rays, even though the same axis of symmetry is involved in both cases. The size of irregularities required to explain the observations is in fact of the order of magnitude likely to be involved in atmospheric turbulence, and it is quite likely that the earth's magnetic field could create substantial nonisotropy in the associated irregularities of electron density. Thus the strength of auroral echoes and their aspect sensitivity could be entirely explained as back-scatter arising from nonisotropic atmospheric turbulence in an E region having a maximum electron density about a hundred times the normal value. Simple turbulence cannot, however, explain the remarkable fading phenomena associated with auroral reflections ( Bowles , 1954).
The Demand for International Reserves and Their Opportunity Cost

An empirical study showing that countries' reserve holdings are sensitive to the rates at which they can borrow on international financial markets, this analysis confirms the view that holding major currencies as reserve assets has costs that are frequently unrecognized. During 1978-82 for 24 sample countries, and during 1978-86 for the same sample less those countries with debt-servicing difficulties, international borrowing costs were found to be a highly significant determinant of reserve holdings--particularly before 1982 for the group that were to have debt difficulties.
A focused two-dimensional air-coupled ultrasonic array for non-contact generation

Abstract Air-coupled ultrasonic sources are relatively inefficient because the high impedance mismatch at the air/solid boundary means that most of the input energy (in air) is reflected at this boundary. The objective of this research is to increase efficiency—specifically an increase in ultrasonic signal amplitude—by designing and building a focused, 2D-array of electrostatic transducers (individual diameters of 38 mm). The operating frequency of this array is in the range of 50–100 kHz; this range is selected for civil infrastructure applications. Numerical simulations are used to design an array by modeling the pressure field in air, and then optimizing an array consisting of 20 transducers to create a line-source. An array is then built (following this design) and the emitted pressure field (in air) of the as built array is measured with a microphone and compared to the pressure field predicted by the numerical model. Finally, the as built focused array is used as an ultrasonic source, and its robustness is verified by comparing the numerical simulation of a transient line-load on an elastic half-space with (completely non-contact) experimentally measured values. There is excellent agreement between these two representations, which confirms the possibility of developing a completely non-contact, scanning ultrasonic system in the 50–100 kHz range.
Thermocapillary convection with undeformable curved surfaces in open cylinders

Abstract Thermocapillary convection driven by a uniform heat flux in an open cylindrical container of unit aspect ratio is investigated by two- and three-dimensional numerical simulations. The undeformable free surface is either flat or curved as determined by the fluid volume (V⩽1) and the Young–Laplace equation. Convection is steady and axisymmetric at sufficiently low values of the Reynolds number (Re) with either flat or curved interfaces. Only steady convection is possible at any Re in strictly axisymmetric computations. Transition to oscillatory three-dimensional motions occurs as Re increases beyond a critical value dependent on Pr and V. Two pulsating and three rotating waves are observed at the free surface with a flat and a concave surface, respectively. The numerical results with either flat or curved free surfaces are in good quantitative agreement with space experiments.
Changes in the nanostructure of non-renewable human lens protein as determined by optical measurements

Investigated problem of aging human lens protein and measured the age-effect in in-vitro lenses by photoluminescence studies. Formulated a model for cataract formation. A chemical means to slow down the process of cataract formation was suggested and checked by non-invasive perturbative colorimetry on in-vivo human lenses.
A Responsive Distributed Routing Algorithm for Computer Networks

A new distributed algorithm is presented for dynamically determining weighted shortest paths used for message routing in computer networks. The major features of the algorithm are that the paths defined do not form transient loops when weights change and the number of steps required to find new shortest paths when network links fail is less than for previous algorithms. Specifically, the worst case recovery time is proportional to the largest number of hops h in any of the weighted shortest paths. For previous loop-free distributed algorithms this recovery time is proportional to h2.
Torsion in rank 1 Drinfeld modules and the uniform boundedness conjecture

It is conjectured that for fixed $A$, $r \ge 1$, and $d \ge 1$, there is a uniform bound on the size of the torsion submodule of a Drinfeld $A$-module of rank $r$ over a degree $d$ extension $L$ of the fraction field $K$ of $A$. We verify the conjecture for $r=1$, and more generally for Drinfeld modules having potential good reduction at some prime above a specified prime of $K$. Moreover, we show that within an $\Lbar$-isomorphism class, there are only finitely many Drinfeld modules up to isomorphism over $L$ which have nonzero torsion. For the case $A=\Fq[T]$, $r=1$, and $L=\Fq(T)$, we give an explicit description of the possible torsion submodules. We present three methods for proving these cases of the conjecture, and explain why they fail to prove the conjecture in general. Finally, an application of the Mordell conjecture for characteristic $p$ function fields proves the uniform boundedness for the $\pp$-primary part of the torsion for rank~2 Drinfeld $\Fq[T]$-modules over a fixed function field.
Hysterectomy, oophorectomy, and endogenous sex hormone levels in older women: the Rancho Bernardo Study.

This study examines the cross-sectional association of hysterectomy and oophorectomy status, chronological age, and years since menopause with plasma levels of total and bioavailable testosterone and estradiol, androstenedione, estrone, and sex hormone-binding globulin (SHBG) in community-dwelling postmenopausal women who were not using estrogen replacement therapy. Six hundred and eighty-four women, aged 50–89 yr, were surveyed for hysterectomy and oophorectomy status and had plasma obtained between 1984–1987. Of these, 438 (67%) had not undergone hysterectomy or oophorectomy (intact), 123 (18%) reported hysterectomy with bilateral oophorectomy, and 123 (18%) reported hysterectomy with conservation of 1 or both ovaries. After adjustment for age and body mass index, both total and bioavailable testosterone levels were reduced by more than 40% (P < 0.001) in hysterectomized women with bilateral oophorectomy compared to those in intact women, with intermediate levels observed in hysterectomized women with o...
LEVERAGING SEMANTIC WEB SEARCH AND BROWSE SESSIONS FOR MULTI-TURN SPOKEN DIALOG SYSTEMS

Training statistical dialog models in spoken dialog systems (SDS) requires large amounts of annotated data. The lack of scalable methods for data mining and annotation poses a significant hurdle for state-ofthe-art statistical dialog managers. This paper presents an approach that directly leverage billions of web search and browse sessions to overcome this hurdle. The key insight is that task completion through web search and browse sessions is (a) predictable and (b) generalizes to spoken dialog task completion. The new method automatically mines behavioral search and browse patterns from web logs and translates them into spoken dialog models. We experiment with naturally occurring spoken dialogs and large scale web logs. Our session-based models outperform the state-of-the-art method for entity extraction task in SDS. We also achieve better performance for both entity and relation extraction on web search queries when compared with nontrivial baselines.