cssi/SciSciGPT-SciSciNet huggingface dataset:
Natural History of Pertussis Antibody in the Infant and Effect on Vaccine Response

To better characterize the transplacental transfer and persistence of pertussis antibodies and their role in the immune response to vaccine, concentrations of pertussis agglutinins and antibodies to lymphocytosis promoting factor (LPF) and filamentous hemagglutinin (FHA) were measured in three distinct groups of serum. Transplacental pertussis IgG antibody concentrations in newborns were found to be comparable to corresponding maternal concentrations and to decline with a half-life of approximately 6 weeks. By the age of 4 months, most infants had no detectable antibodies to LPF or FHA. Higher concentrations of maternally derived antibody to LPF were associated with a significantly weaker antibody response to conventional vaccine. In contrast, acellular vaccine stimulated superior antibody production, regardless of antecedent concentrations of antibody to LPF. The data support continuation of the current schedule of pertussis immunization and further efforts to develop an acellular vaccine for use in young infants.
Electronic polarization in pentacene crystals and thin films

Electronic polarization is evaluated in pentacene crystals and in thin films on a metallic substrate using a self-consistent method for computing charge redistribution in nonoverlapping molecules. The optical dielectric constant and its principal axes are reported for a neutral crystal The polarization energies P + and P - of a cation and anion at infinite separation are found for both molecules in the crystal's unit cell in the bulk, at the surface, and at the organic-metal interface of a film of N molecular layers. We find that a single pentacene layer with herring-bone packing provides a screening environment approaching the bulk. The polarization contribution to the transport gap P=P + + P - , which is 2.01 eV in the bulk, decreases and increases by only ∼ 10% at surfaces and interfaces, respectively. We also compute the polarization energy of charge-transfer states with fixed separation between anion and cation, and compare to electroabsorption data and to submolecular calculations. Electronic polarization of ∼ I eV per charge has a major role for transport in organic molecular systems with limited overlap.
Social stigma, HIV/AIDS knowledge, and sexual risk

A cross-sectional study of 481 sexually active, heterosexual late adolescents showed that: (a) heterosexual people may be distancing themselves from HIV/AIDS because of its association with the gay community while also engaging in greater behavioral risk for HIV/AIDS; and (b) the ways a person comes to know about HIV/AIDS (perceived knowl­ edge, passive classroom learning, media influence, and knowing people with HIV/AIDS) can be related to sexual risk behavior through the operation of two mediating variables, condom self-efficacy and perceived HIV/AIDS risk. The variables studied are closely linked with Stage 1 factors in the AIDS Risk Reduction Model. Implications for understanding how stigmatizing can affect behavior are discussed, as well as implications for education in HIV/AIDS related issues. Since 1990, the total number of United States AIDS cases among homosexu­ als has been leveling off, indicating that this population has been effective to some extent in changing risk behavior. Trends in United States AIDS incidence rates, however, indicate that the number of cases diagnosed as a result of hetero­ sexual transmission is increasing (Centers for Disease Control and Prevention, 1997), and projections indicate that this trend will continue. This continued increase in heterosexual transmission indicates that heterosexuals, as a group, are not responding to current interventions and education about risk behavior change. It has been suggested that the identification of AIDS with persons and groups already stigmatized prior to the epidemic (i.e., homosexuals) increases hostility toward the disease and people with the disease (Caldwell, 1991; Herek & Cogan, 1995; Herek & Glunt, 1988; Kadushin, 1996; Ross & Rosser, 1996). Although the total number of persons with AIDS (PWAs) who are under age 20 is relatively small, this is misleading because of the long incubation period for
Conditioned taste aversion induced by motion is prevented by selective vagotomy in the rat

The role of the vagus nerve in motion-induced conditioned taste aversion (CTA) was studied in hooded rats. Animals with complete, selective gastric vagotomy failed to form conditioned taste aversion after multiple conditioning sessions in which the conditioned stimulus (a cider vinegar solution) was drunk immediately before a 30-min exposure to vertical axis rotation at 150°/s. Results are discussed with reference to the use of CTA as a measure of motion-induced “sickness” or gastrointestinal disturbance, and, because motion-induced CTA requires that both the vagus nerve and the vestibular apparatus be intact, in light of the possible convergence of vagal and vestibular functions.
New synthesis of (RS)‐carnitine chloride

A four-step synthesis of (RS)-carnitine chloride was developed using extremely mild reaction conditions and versatile intermediates. Crotyl chloride was converted to tert-butyl 3-butenoate using tert-butyl alcohol and triethylamine in ether. Treatment of tert-butyl 3-butenoate with m-chloroperbenzoic acid in chloroform afforded tert-butyl 3,4-epoxybutyrate. Reaction of this compound with trimethylamine hydrochloride in methanol, followed by mild acid hydrolysis of the tert-butyl ester, afforded (RS)-carnitine chloride.
Characteristics of gamma-ray line flares

Observations of solar gamma rays by the Solar Maximum Mission (SMM) demonstrate that energetic protons and ions are rapidly accelerated during the impulsive phase. To understand the acceleration mechanisms for these particles, the characteristics of the gamma ray line flares observed by SMM were studied. Some very intense hard X-ray flares without detectable gamma ray lines were also investigated. Gamma ray line flares are distinguished from other flares by: (1) intense hard X-ray and microwave emissions; (2) delay of high energy hard X-rays; (3) emission of type 2 and/or type 4 radio bursts; and (4) flat hard X-ray spectra (average power law index: 3.1). The majority of the gamma ray line flares shared all these characteristics, and the remainder shared at least three of them. Positive correlations were found between durations of spike bursts and spatial sizes of flare loops as well as between delay times and durations of spike bursts.
UTa2O(S2)3Cl6: A ribbon structure containing a heterobimetallic 5d–5f M3 cluster

A new solid-state compound containing a heterobimetallic cluster of U and Ta, UTa{sub 2}O(S{sub 2}){sub 3}Cl{sub 6}, has been synthesized and its structure has been characterized by single-crystal X-ray diffraction methods. UTa{sub 2}O(S{sub 2}){sub 3}Cl{sub 6} was synthesized from UCl{sub 4} and Ta{sub 1.2}S{sub 2} at 883 K. The O is believed to have originated in the Ta{sub 1.2}S{sub 2} reactant. The compound crystallizes in the space group P1-bar of the triclinic system. The structure comprises a UTa{sub 2} unit bridged by mu{sub 2}-S{sub 2} and mu{sub 3}-O groups. Each Ta atom bonds to two mu{sub 2}-S{sub 2}, the mu{sub 3}-O, and two terminal Cl atoms. Each U atom bonds to two mu{sub 2}-S{sub 2}, the mu{sub 3}-O, and four Cl atoms. The Cl atoms bridge in pairs to neighboring U atoms to form a ribbon structure. The bond distances are normal and are consistent with formal oxidation states of +IV/+V/-II/-I/-I for U/Ta/O/S/Cl, respectively. The optical absorbance spectrum displays characteristic transition peaks near the absorption edge. Density functional theory was used to assign these peaks to transitions between S{sup 1-} valence-band states and empty U 5f-6d hybrid bands. Density-of-states analysis shows overlap between Ta 5d and U bands, consistent withmore » metal-metal interactions. - The UTa2O(S2)3Cl6 cluster with completed coordination sphere around uranium« less
Europium nitrate complexation in aqueous methanol

Abstract In aqueous methanol in the presence of nitrate, Eu(III) forms Eu(NO 3 ) 2+ , Eu(NO 3 ) 2 + and Eu(NO 3 ) 3 complexes. At 25 °C and a water mole fraction of 0.01, K 1 = 168.4 ± 14.8, K 2 = 114.6 ± 5.2 and K 3 = 41.1 ± 3.6. As the water mole fraction increases, the magnitude of each of the equilibrium constants decreases. In water, the tris complex is not present. No complexes are detected between Eu(III) and ClO 4 - between water mole fractions of 0.01 to 1.00. The behavior of Eu(III) in aqueous methanol appears to be somewhat different than that for Er(III) in aqueous methanol under similar conditions.
Recess, Physical Education, and Elementary School Student Outcomes.

Today’s children experience a decreased amount of time at recess and fewer physical education (PE) classes throughout the school day. Breaks for physical activity limit class time for academics, potentially reducing learning. However, breaks may improve alertness and achievement. Using the Early Childhood Longitudinal Survey Kindergarten Class of 1998-1999, we evaluate how recess and PE in elementary school influence children’s learning. We find no statistically significant or economically significant impacts of weekly recess or PE time on student learning for kindergarteners through fifth graders. For example, in kindergarten, adding an hour a week of recess reduces the average test score gain in reading by a statistically insignificant 0.01 standard deviations. An additional 49 minutes per week of PE in kindergarten improves reading test score gains by a statistically insignificant 0.05 standard deviations. We find no statistical difference in the male and female students’ response to recess and PE. Evidence suggests that recess and PE do not harm student outcomes.
Accessing Skeletal Diversity Using Catalyst Control: Formation of n and n + 1 Macrocyclic Triazole Rings

A regioselective intramolecular Huisgen cycloaddition was performed on various azido alkyne substrates giving rise to macrocyclic triazole rings. Using catalyst control, a common intermediate has been converted to two structurally unique macrocycles with either a 1,5- or a 1,4-triazole resulting in an n or n + 1 ring size. This is the first example of an intramolecular ruthenium-catalyzed Huisgen cycloaddition.
A new infinite class of quiver gauge theories

We construct a new infinite family of = 1 quiver gauge theories which can be Higgsed to the Yp,q quiver gauge theories. The dual geometries are toric Calabi-Yau cones for which we give the toric data. We also discuss the action of Seiberg duality on these quivers, and explore the different Seiberg dual theories. We describe the relationship of these theories to five dimensional gauge theories on (p,q) 5-branes. Using the toric data, we specify some of the properties of the corresponding dual Sasaki-Einstein manifolds. These theories generically have algebraic R-charges which are not quadratic irrational numbers. The metrics for these manifolds still remain unknown.
S-matrix studies of resonances in A = 3, 4, 5, 6, and 12 nucleon systems

Abstract Resonances of certain light nuclei are explored by studying the complex pole structures of the scattering matrices. Among other results we predict the existence of three-neutron and three-proton resonances, a small spin-orbit splitting in the low-lying 5 He and 5 Li states, and the nonexistence of the soft dipole resonance in 6 He.
Enumerative and asymptotic analysis of a moduli space

We study exact and asymptotic enumerative aspects of the Hilbert series of the cohomology ring of the moduli space of stable pointed curves of genus zero. This manifold is related to the WDVV (Witten-Dijkgraaf-Verlinde-Verlinde) equations of string theory.
Joint detection-Estimation of Gaussian signals in white Gaussian noise

Recent results on joint detection-estimation for discrete data are extended to the continuous case for Gaussian signals in white Gaussian noise. Stochastic differential equations are obtained describing the temporal evolution of the sufficient statistic for the minimum Bayes' risk detection and the optimal mean-square error estimate of the signal state vector. An approximate solution for the estimation equation is presented and the results are extended to the case of multishot joint detection estimation.
Long-Term Photometric Analysis of the Active W UMa-Type System TU Bootis

We present multicolor light curves for the W UMa-type eclipsing binary TU Boo for two epochs separated by 22 years. An analysis of the O – C diagram indicates the earlier observations took place right in the middle of a major period change, thus allowing for a unique study on mass transfer and period changes in this W UMa-type system. We compute model fits to our light curves, along with the only other published set, using the Wilson-Devinney program, and find temporally correlated changes in the size of the secondary component with anomalies in the O – C diagram. We investigate the cause of these changes and find support for the existence of rapid, large-scale mass transfer between the components. We postulate that this interaction allows them to maintain nearly equal surface temperatures despite having achieved only marginal contact. We also find support for the evolutionary scenario in which TU Boo has undergone a mass ratio reversal in the past, due to large-scale mass transfer so that what is presently the secondary component of TU Boo is in an advanced evolutionary state, oversized due to a helium-enriched core, with a total system age of ≥10 Gyr.
Electrosynthesis of new stereoisomers of alkyl- and arylthio derivatives of levoglucosenone

Abstract Cathodically initiated Michael addition of thiols to levoglucosenone using small currents produces the previously unknown threo addition product in several instances. The normal erythro isomer, identified as the kinetic product, tends to be formed when large currents are used. The slow, low current electrolyses promote equilibration of the two forms so that erythro can be converted to threo by the retro reaction and readdition. Additions to R-(+)-apoverbenone and R-(-)-carvone are also reported.
Direct evidence for prolonged magnetic reconnection at a continuous x-line within the heliospheric current sheet

[1] Observations by 5 spacecraft of an exceptionally broad (1.85 × 106 km) Petschek-type reconnection exhaust within the heliospheric current sheet, HCS, in the solar wind at 1 AU on 31 August and 1 September 2001 provide convincing direct evidence for prolonged (at least 5 hours) magnetic reconnection at a continuous X-line in the solar wind. At least 1.2 × 1024 ergs of magnetic energy were extracted from the HCS in this event and converted to kinetic and thermal energy of the exhaust plasma. The reconnection produced field lines disconnected from the Sun and may have originated inside the point where the solar wind became super-Alfvenic, thereby slightly reducing the amount of open magnetic flux present in the heliosphere.
Integrable four-dimensional symplectic maps of standard type

Abstract We search for rotational, four-dimensional maps of standard type (x n+1 −2x n +x n−1 =ϵƒ(x, ϵ)) possesing one or two polynomial integrals. There are no nontrivial maps corresponding to cubic oscillators, but we find a four-parameter family of such maps corresponding to quartic oscillators. This seems to be the only such example.
An EMT–Driven Alternative Splicing Program Occurs in Human Breast Cancer and Modulates Cellular Phenotype

Epithelial-mesenchymal transition (EMT), a mechanism important for embryonic development, plays a critical role during malignant transformation. While much is known about transcriptional regulation of EMT, alternative splicing of several genes has also been correlated with EMT progression, but the extent of splicing changes and their contributions to the morphological conversion accompanying EMT have not been investigated comprehensively. Using an established cell culture model and RNA–Seq analyses, we determined an alternative splicing signature for EMT. Genes encoding key drivers of EMT–dependent changes in cell phenotype, such as actin cytoskeleton remodeling, regulation of cell–cell junction formation, and regulation of cell migration, were enriched among EMT–associated alternatively splicing events. Our analysis suggested that most EMT–associated alternative splicing events are regulated by one or more members of the RBFOX, MBNL, CELF, hnRNP, or ESRP classes of splicing factors. The EMT alternative splicing signature was confirmed in human breast cancer cell lines, which could be classified into basal and luminal subtypes based exclusively on their EMT–associated splicing pattern. Expression of EMT–associated alternative mRNA transcripts was also observed in primary breast cancer samples, indicating that EMT–dependent splicing changes occur commonly in human tumors. The functional significance of EMT–associated alternative splicing was tested by expression of the epithelial-specific splicing factor ESRP1 or by depletion of RBFOX2 in mesenchymal cells, both of which elicited significant changes in cell morphology and motility towards an epithelial phenotype, suggesting that splicing regulation alone can drive critical aspects of EMT–associated phenotypic changes. The molecular description obtained here may aid in the development of new diagnostic and prognostic markers for analysis of breast cancer progression.
Resurgence theory, ghost-instantons, and analytic continuation of path integrals

A general quantum mechanical or quantum field theoretical system in the path integral formulation has both real and complex saddles (instantons and ghost-instantons). Resurgent asymptotic analysis implies that both types of saddles contribute to physical observables, even if the complex saddles are not on the integration path i.e., the associated Stokes multipliers are zero. We show explicitly that instanton-anti-instanton and ghost-anti-ghost saddles both affect the expansion around the perturbative vacuum. We study a self-dual model in which the analytic continuation of the partition function to negative values of coupling constant gives a pathological exponential growth, but a homotopically independent combination of integration cycles (Lefschetz thimbles) results in a sensible theory. These two choices of the integration cycles are tied with a quantum phase transition. The general set of ideas in our construction may provide new insights into non-perturbative QFT, string theory, quantum gravity, and the theory of quantum phase transitions.
New technology for the construction of bicyclo [6.2.1] ring systems

Abstract Three new methods are presented in this synthesis of an 11-oxabicyclo[6.2.1]-undec-1,5,9-triene. They include: (1) the preparation of the dianion of 3-hydroxy-1,4-pentadiene; (2) an intramolecular Diels-Alder reaction accelerated by silica gel saturated with water; and (3) a tandem Grob fragmentation and homoallylic elimination of a cyclic sulfate. Overall, the synthesis of (1 E , 5 E , 9 Z )-2-(t-Butyldimethylsiloxy)-8-methyl-11-oxabicyclo[6.2.1]-undec-1,5,9-triene ( 1 ) was completed in 9 steps starting from 5-methylfurfural.
Heavy quark fragmenting jet functions

Heavy quark fragmenting jet functions describe the fragmentation of a parton into a jet containing a heavy quark, carrying a fraction of the jet momentum. They are two-scale objects, sensitive to the heavy quark mass, m Q , and to a jet resolution variable, τ N .We discuss how cross sections for heavy flavor production at high transverse momentum can be expressed in terms of heavy quark fragmenting jet functions, and how the properties of these functions can be used to achieve a simultaneous resummation of logarithms of the jet resolution variable, and logarithms of the quark mass. We calculate the heavy quark fragmenting jet function $ \mathcal{G}_Q^Q $ at $ \mathcal{O}\left( {{\alpha_s}} \right) $ , and the gluon and light quark fragmenting jet functions into a heavy quark, $ \mathcal{G}_g^Q $ and $ \mathcal{G}_l^Q $ at $ \mathcal{O}\left( {\alpha_s^2} \right) $ . We verify that, in the limit in which the jet invariant mass is much larger than m Q , the logarithmic dependence of the fragmenting jet functions on the quark mass is reproduced by the heavy quark fragmentation functions. The fragmenting jet functions can thus be written as convolutions of the fragmentation functions with the matching coefficients $ {{\mathcal{J}}_{ij }} $ , which depend only on dynamics at the jet scale. We reproduce the known matching coefficients $ {{\mathcal{J}}_{ij }} $ at $ \mathcal{O}\left( {{\alpha_s}} \right) $ , and we obtain the expressions of the coefficients $ {{\mathcal{J}}_{gQ }} $ and $ {{\mathcal{J}}_{lQ }} $ at $ \mathcal{O}\left( {\alpha_s^2} \right) $ . Our calculation provides all the perturbative ingredients for the simultaneous resummation of logarithms of m Q and τ N .
Aryl nitro group substitution by primary and secondary amines

Abstract Primary and secondary amines react with 1,2-dihalo-4,5-dinitrobenzene to give nitro group substitution at mild temperatures. The halogen substituents on the ring remain unsubstituted and can be used for further reaction chemistry.
On the minimum energy of sending Gaussian multiterminal sources over the Gaussian MAC

We study the minimum energy of sending Gaussian multiterminal sources over the Gaussian multiple access channel (MAC). Distributed transmitters observe Gaussian multiterminal sources and describe their observations to a central decoder, which desires to reconstruct the sources under MSE constraints. We first lower bound the minimum energy by a cut-set argument which couples the transmitted signals and reconstruction errors. For achievability, separate source-channel coding is first studied as a benchmark. We then find out the minimum energy that can be achieved uncoded transmission. A hybrid digital/analog scheme is proposed to achieve the best known energy performance.
Plasma Insulin-Like Growth Factor-I and Prostate Cancer Risk: A Prospective Study

Insulin-like growth factor-I (IGF-I) is a mitogen for prostate epithelial cells. To investigate associations between plasma IGF levels and prostate cancer risk, a nested case-control study within the Physicians' Health Study was conducted on prospectively collected plasma from 152 cases and 152 controls. A strong positive association was observed between IGF-I levels and prostate cancer risk. Men in the highest quartile of IGF-I levels had a relative risk of 4.3 (95 percent confidence interval 1.8 to 10.6) compared with men in the lowest quartile. This association was independent of baseline prostate-specific antigen levels. Identification of plasma IGF-I as a predictor of prostate cancer risk may have implications for risk reduction and treatment.
Synthesis of Functionalized Dialkyl Ketones From Carboxylic Acid Derivatives and Alkyl Halides

Unsymmetrical dialkyl ketones can be directly prepared by the nickel-catalyzed reductive coupling of carboxylic acid chlorides or (2-pyridyl)thioesters with alkyl iodides or benzylic chlorides. A wide variety of functional groups are tolerated by this process, including common nitrogen protecting groups and C–B bonds. Even hindered ketones flanked by tertiary and secondary centers can be formed. The mechanism is proposed to involve the reaction of a (L)Ni(alkyl)2 intermediate with the carboxylic acid derivative.
Vacuum calorimetry in exploding wire studies

A method of using vacuum calorimetry as a means of determining directly the energy deposited in an electrically exploded wire is presented. This energy determination is compared with that given by the time integral of the product of voltage and current. A definite reproducible pattern of the explosion products is deposited on the walls of the calorimeter, which may be used as a means of understanding the behavior of the wire during the explosion.
Toward a broad spectrum decontaminant for reactive toxic phosphates/phosphonates: N-alkyl-3-iodosopyridinium-4-carboxylates

Abstract N - n -hexadecyl-3-iodosopyridinium-4-carboxylate has p K a p -nitrophenyldiphenyl phosphate in acidic solution.
A simple model of solar variability influence on climate

Abstract We present a simple dynamic model of solar variability influence on climate, which is truncated from the stratospheric wave-zonal flow interaction dynamics over a β-plane. The model consists of three ordinary differential equations controlled by two parameters: the initial amplitude of planetary waves and the vertical gradient of the zonal wind. The changes associated with the solar UV variability, as well as with seasonal variations, are introduced as periodic modulations of the zonal wind gradient. Influence of the Quasi-Biennial Oscillation is included as a periodic change of the width of the latitudinal extent of the β-plane. The major climate response to these changes is seen through modulation of the number of cold and warm winters.
Renormalization Group Maps for Ising Models in Lattice-Gas Variables

Real-space renormalization group maps, e.g., the majority rule transformation, map Ising-type models to Ising-type models on a coarser lattice. We show that each coefficient in the renormalized Hamiltonian in the lattice-gas variables depends on only a finite number of values of the renormalized Hamiltonian. We introduce a method which computes the values of the renormalized Hamiltonian with high accuracy and so computes the coefficients in the lattice-gas variables with high accuracy. For the critical nearest neighbor Ising model on the square lattice with the majority rule transformation, we compute over 1,000 different coefficients in the lattice-gas variable representation of the renormalized Hamiltonian and study the decay of these coefficients. We find that they decay exponentially in some sense but with a slow decay rate. We also show that the coefficients in the spin variables are sensitive to the truncation method used to compute them.
Triple-Nucleoside Analog Antiretroviral Therapy: Is There Still a Role in Clinical Practice? A Review

The development and widespread clinical use of coformulated abacavir/lamivudine/zidovudine (ABC/3TC/ZDV) as Trizivir represented an important advance in the management of HIV-infected patients, especially those with adherence challenges. With a low pill burden, no food restrictions, limited drug-drug interactions, and a favorable resistance profile, ABC/3TC/ZDV remains an alternative option in the US Department of Health and Human Services Consensus Panel Guidelines as initial treatment in antiretroviral-naive patients. Recent data have shown ABC/3TC/ZDV to be less efficacious in suppressing and/or maintaining suppression of virologic replication compared with efavirenz-containing antiretroviral therapy. Although triple-nucleoside/nucleotide reverse transcriptase inhibitor (t-NRTI) combinations that do not contain a thymidine analog (ZDV or stavudine) have recently shown high virologic failure rates in clinical trials and clinical practice, t-NRTI regimens containing a thymidine analog have consistently been shown to be efficacious.
The Logical Complexity of Geometric Properties in the Plane

This paper studies the logical complexity of geometric properties in the plane. These properties are characterized according to the length of formulas necessary to express them. In this study a portion of the plane X will be considered as a collection of squares {x1, ..., xn} arranged into a fine grid. A pattern P is a subset of X and the grid is assumed to be fine enough so that approximations to geometrical figures can be obtained. P can be defined by mapping m: X →{0,1} where for x e X, m(x) = 1 iff x e P. A set of patterns or a geometrical property ℘ can be expressed as a Boolean function f on the n variables x1, ..., xn such that the value of f is 1 under the assignment m iff P e ℘.
Flame turbulence studies

Abstract Measurements of the turbulent structure of a premixed turbulent propane-air flame have been made by using a remote sensing, double-laser schlieren instrument which operates on a cross-correlation principle. Development, calibration, and improvements made for application to flames are presented and discussed. Measurements in the post flame-front region of a stoichiometric flame indicate that the front is disrupted and forms flame kernels which burn rapidly outward from their centers as they are convected downstream. The response of the laser schlieren to spherical kernels has been analyzed, and the results have been applied to the flame measurements in order to estimate the size distributions of the kernels along the flame centerline.
New Phases in the CaO–M2O3–CuO (M = Nd, Gd, Y) Systems at 1000°C

New layered cuprates with the general stoichiometry Ca{sub 2+x}M{sub 2{minus}x}Cu{sub 5}O{sub 10} have been characterized for M = Nd, Gd, and Y. This paper reports these insulating phases having structures closely related to that of NaCuO{sub 2} and contain one-dimensional chains constructed from edge-sharing (CuO{sub 4}) square planes. The x-ray patterns of these ternary cuprate phases are complicated by strong reflections from both incommensurate and commensurate supercells which result from the ordering of the Ca{sup 2+} and M{sup 3+} ions in the structure. The stoichiometry range, and resultant Cu valences in these cuprates depend upon the nature of the trivalent ion. Ca-rich and trivalent-rich compositions can be prepared for M = Nd and Gd, but only Ca-rich compositions were formed in the Y system. No other ternary phases are observed under the conditions of this study, 1000{degrees}C in air, and the solid-state equilibria are dominated by the single ternary phase identified above.
Oligosaccharide synthesis: from conventional methods to modern expeditious strategies.

Abstract Although glycoscientists have learned over the years how to isolate certain classes of naturally occurring complex carbohydrates, the availability of pure natural isolates, remains inadequate to address the ongoing challenges. As a result, glycoscientists have turned to chemical synthesis for access to complex oligosaccharides and glycoconjugates. Efficient chemical synthesis of complex carbohydrates can yield significant quantities of the pure natural structures as well as unnatural mimetics that are often of interest. Traditional oligosaccharide synthesis, however, often requires extensive protecting‐group manipulations between each glycosylation step. Such additional manipulations increase the number of total synthetic steps and inevitably decrease the efficiency, as reflected in a dramatic drop in yield. This chapter classifies and discusses significant recent improvements that have emerged to address the drawbacks of the traditional approach. Expeditious new strategies effectively shorten the task of oligosaccharide assembly by minimizing the need for protecting‐group manipulations between glycosylation steps, or even purification of the intermediates. The excellent innovations surveyed here have already facilitated synthesis of complex oligosaccharides and glycoconjugates, and some representative examples are discussed herein.
Bose-Einstein condensation of lithium

Li has been studied in a magnetically trapped gas. Many-body quantum theory predicts that the occupation number of the condensate is limited to about 1400 atoms because of the effectively attractive interactions between 7Li atoms. Using a versitile phase-contrast imaging technique, we experimentally observe the condensate number to be consistent with this limit. We discuss our measurements, the current theoretical understanding of BEC in a gas with attractive interactions, and future experiments we hope to perform.
Solow and the states: New evidence

Yamarik S. (2006) Solow and the states: new evidence, Regional Studies 40, 571–582. The aim of this study is to reassess the sources behind US state-level growth during the post-war period. It improves upon the existing literature (1) by using a general method-of-moments (GMM) estimator that eliminates omitted variable and endogeneity bias, (2) by allowing for parameter heterogeneity, and (3) by extending the sample to the pre- and post-productivity slowdown periods. Unlike previous regional growth studies, the paper supports both predictions of neoclassical growth theory. First, strong evidence of convergence in state-level growth rates is found. Second, the rate of convergence and capital share are inversely related. Moreover, numerical computations show that the estimated values for the convergence rate and capital share are consistent with the neoclassical growth model. Yamarik S. (2006) Solow et les Etats: de nouvelles preuves, Regional Studies 40, 571–582. Cette etude cherche a reevaluer les origine...
Stereoselective intramolecular enone-olefin photocycloadditions of 1,7-dienes: Model studies on the synthesis of lycopodium alkaloids

The synthesis and stereoselective intramolecular [2+2] photocycloaddition reactions of enones 4a and 4s has been accomplished, yielding possible precursors for the development of a total synthesis of several lycopodium alkaloids.
Non-Abelian Berry phase and Chern numbers in higher spin-pairing condensates

We show that the non-Abelian Berry phase emerges naturally in the $s$-wave and spin quintet pairing channel of spin-$3∕2$ fermions. The topological structure of this pairing condensate is characterized by the second Chern number. This topological structure can be realized in ultracold atomic systems and in solid state systems with at least two Kramers doublets.
The entropy of the microwave background and the acceleration of the universe

If the present acceleration of the universe is due to a cosmological constant, λ, then the entropy of the microwave background is bounded. It cannot exceed λ−3/4 ~ 1091, which is much less than the entropy of empty de Sitter space λ−1 ~ 10122. This is due to the limited efficiency of storing entropy by local field theoretical degrees of freedom. The observed entropy of the microwave background is of O(1085).
An inequality on global alliances for trees

Given a graph G = ( V , E ) , a dominating set S is called a global defensive (respectively offensive) alliance if in the closed neighborhood of every vertex in S (respectively, V - S ) at least half of the vertices are from S . The global defensive (offensive) alliance number of G is the cardinality of a minimum size global defensive (offensive) alliance in G and is denoted by γ a ( G ) ( γ o ( G ) ) . In this paper, we prove the following inequality: γ o ( T ) + 1 3 ? γ a ( T ) + n 6 if T is a tree with n vertices. We prove our inequality by incrementally changing a defensive alliance into an offensive alliance and bounding the modification using a double-counting method on the edges of the graph. We also construct an example to show that the inequality is sharp. Our result answers a question of Harutyunyan in a stronger form.
A82775b and a82775c, novel metabolites of an unknown fungus of the order sphaeropsidales

Compounds A82775B (1) and A82775C (2) were isolated as non-antimicrobial by-products during attempts to isolate an elusive G+, G- antibiotic from culture A82775. an unidentified mold. A82775 factors B and C are present in both the mycelium and filtered broth. The metabolites were recovered from the filtered broth by adsorption on Diaion HP-20 nonfunctionalized macroreticular resin and purified by preparative reverse phase HPLC on C18 bonded phase supports. The structure elucidation of A82775 factors B (1) and C (2) has been accomplished by spectroscopic means including COSY, NOESY, INAPT, HMQC and 2D-INADEQUATE NMR experiments.
A Dual-Catalysis/Anion-Binding Approach to the Kinetic Resolution of Allylic Amines

A dual-catalysis approach enables the small-molecule catalyzed kinetic resolution of allylic amines by acylation. By employing 2 mol % of each 4-(pyrrolidino)pyridine (PPY) and a readily available chiral hydrogen-bonding cocatalyst, the first nonenzymatic kinetic resolution of allylic amines was accomplished with s factors of up to 20.
Development of Breathing Rat-Lung Models for Particulate Deposition Studies

ABSTRACT Techniques have been developed for casting both solid and hollow lung models from rat-lung specimens. To make a solid model, an air line at a positive pressure of 25 cm of water was connected to the trachea to air-dry lungs which had been removed surgically from the animal. Using the lost wax technique, a hollow cast of the airways and the nasopharynx was made. A mechanical breathing system, capable of simulating different breathing patterns, was developed.
Thermodynamics of the Heisenberg ferromagnet in an applied magnetic field.

The anisotropic-Heisenberg-ferromagnet formalism developed previously is examined to include an applied magnetic field for the isotropic case in the random-phase approximation. Thermodynamic quantities such as magnetization, susceptibility, and the derivative of magnetization with respect to temperature are studied near the Curie point.
The Bousfield lattice for truncated polynomial algebras

The global structure of the unbounded derived category of a truncated polynomial ring on countably many generators is investigated, via its Bousfield lattice. The Bousfield lattice is shown to have cardinality larger than that of the real numbers, and objects with large tensor-nilpotence height are constructed.
Co-optimization of generation unit commitment and transmission switching with N-1 reliability

Currently, there is a national push for a smarter electric grid, one that is more controllable and flexible. The full control of transmission assets are not currently built into electric network optimization models. Optimal transmission switching is a straightforward way to leverage grid controllability: to make better use of the existing system and meet growing demand with existing infrastructure. Previous papers have shown that optimizing the network topology improves the dispatch of electrical networks. Such optimal topology dispatch can be categorized as a smart grid application where there is a co-optimization of both generators and transmission topology. In this paper we present a co-optimization formulation of the generation unit commitment and transmission switching problem while ensuring N-1 reliability. We show that the optimal topology of the network can vary from hour to hour. We also show that optimizing the topology can change the optimal unit commitment schedule. This problem is large and computationally complex even for medium sized systems. We present decomposition and computational approaches to solving this problem. Results are presented for the IEEE RTS 96 test case.
Structure functions, form factors, and lattice QCD

Abstract We present results towards the calculation of the pion electric form factor and structure function on a 16 3 × 24 lattice using charge overlap. By sacrificing Fourier transform information in two directions, it is seen that the longitudinal four point function can be extracted with reasonable error bars at low momentum.
The unusual rearrangement of N‐nitroso‐N,O‐dibenzylhydroxylamines with acetic anhydride

Treatment of N-nitroso-N,O-dibenzylhydroxylamine (2a) with acetic anhydride in benzene at reflux results in a remarkable rearrangement to 2-benzoyl-1-acetylbenzylhydrazine and it was established that it is the N-benzyl substituent of 2a that is transformed into the benzoyl group of the rearranged product (3a).
A simplified method of estimating the response of light aircraft to continuous atmospheric turbulence

Light rigid civil aircraft response to continuous atmospheric turbulence estimated using two rigid body degrees of freedom method for vertical and lateral gusts
Quasimaps, straightening laws, and quantum cohomology for the Lagrangian Grassmannian

The Drinfel’d Lagrangian Grassmannian compactifies the space of algebraic maps of fixed degree from the projective line into the Lagrangian Grassmannian. It has a natural projective embedding arising from the canonical embedding of the Lagrangian Grassmannian. We show that the defining ideal of any Schubert subvariety of the Drinfel’d Lagrangian Grassmannian is generated by polynomials which give a straightening law on an ordered set. Consequentially, any such subvariety is Cohen–Macaulay and Koszul. The Hilbert function is computed from the straightening law, leading to a new derivation of certain intersection numbers in the quantum cohomology ring of the Lagrangian Grassmannian.
Coulomb oscillations in partially open quantum dots

Abstract We report tunneling measurements of the Coulomb blockade in a single quantum dot at zero magnetic field and dilution refrigerator temperatures with weak tunneling from the dot to one lead (the ‘closed’ lead, conductance G closed ) and strong tunneling to the other lead (the ‘open’ lead, conductance G open ). We observe suppression of the Coulomb oscillations with G open ≈2 e 2 / h , and then see the oscillations return for G open >2 e 2 / h . The oscillations show a strikingly lower threshold temperature at G open ≈2 e 2 / h than for greater or lesser G open .
Formation of single-wall carbon nanotube superbundles

Since their discovery in 1993, carbon single-wall nanotubes (SWNTs) have been of great interest because of their expected novel electronic, mechanical, and gas adsorption properties. Difficulties arise in measuring these various properties because the SWNTs currently available for analyses have very small bundle sizes (10--20 nm) and are typically in random orientations. A vital step for the industrial application of SWNTs is to align the individual tubes into bundles of a size that allows facile measurement of the various physical and chemical properties. This paper is the first to illustrate a set of procedures for the preparation and isolation of aligned SWNT superbundles.
Overscreened Kondo fixed point in S=1 spin liquid

We propose a possible realization of the overscreened Kondo impurity problem by a magnetic $s=1/2$ impurity embedded in a two-dimensional $S=1$ $U(1)$ spin liquid with a Fermi surface. This problem contains an interesting interplay between non-Fermi-liquid behavior induced by a $U(1)$ gauge field coupled to fermions and a non-Fermi-liquid fixed point in the overscreened Kondo problem. Using a large-$N$ expansion together with an expansion in the dynamical exponent of the gauge field, we find that the coupling to the gauge field leads to weak but observable changes in the physical properties of the system at the overscreened Kondo fixed point. We discuss the extrapolation of this result to a physical case and argue that the realization of overscreened Kondo physics could lead to observations of effects due to gauge fields.
Infrared Detector Characteristics; Measurement And Use

Infrared photodetectors having electrical outputs directly proportional to the radiant signal power input can be described in terms of specific and well defined parameters. These parameters and the associated measurement techniques are briefly outlined. Methods are suggested for extrapolating and interpolating from standard report data in order to prepare specific engineering information about expected operational detector performances. Some emphasis is placed on calculating a figure)/ v ss which gives a comparison of quantum detector's response to that of a "black" or "gray" detector for a given spectral content of incident radiant flux. The discussion contains information on current state-of-the-art detectors including those fabricated from the pseudobinary alloy semiconductors mercury-cadmium telluride and the lead-tin chalcogenides.© (1976) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Enantioselective Friedel-Crafts alkylations catalyzed by bis(oxazolinyl)pyridine-scandium(III) triflate complexes.

The enantioselective Friedel−Crafts addition of a variety of indoles catalyzed by bis(oxazolinyl)pyridine−scandium(III) triflate complexes (Sc(III)−pybox) was accomplished utilizing a series of β-substituted α,β-unsaturated phosphonates and α,β-unsaturated 2-acyl imidazoles. The acyl phosphonate products were efficiently transformed into esters and amides, whereas the acyl imidazole adducts were converted to a broader spectrum of functionalities such as esters, amides, carboxylic acids, ketones, and aldehydes. The sense of stereoinduction and level of enantioselectivity were found to be functions of the size of the substrate employed, the substitution on the ligand, and the catalyst loading. Molecular modeling of the catalyst with the bound substrates was performed based on the crystal structures of the catalyst complexes and the sense of stereoinduction observed in the addition reaction. Nonlinear effects over a range of catalyst concentrations implicate a mononuclear complex as the active catalyst.
Evaluating a Call Option and Optimal Timing Strategy in the Stock Market

The optimal strategy for the holder of a “put” or “call” option contract in the stock market is studied under the random walk model for stock prices. Some results are distribution-free in that they depend only on the mean price change. Other results are derived under the assumption that price changes have a normal or Gaussian distribution. Under this assumption explicit results are obtained for the limiting case where the expiration date of the contract is indefinitely far in the future. Knowing the optimal strategy it is possible to evaluate whether the purchase of a given option can be expected to be profitable.
Magnetic nanostructures for advanced technologies: fabrication, metrology and challenges

Magnetic nanostructures are an integral part to many state-of-the-art and emerging technologies. However, the complete path from parts (the nanostructures) to the manufacturing of the end products is not always obvious to students of magnetism. The paper follows this path of the magnetic nanostructure, and explains some of the steps along the way: What are the technologies that employ magnetic nanostructures? How are these nanostructures made? What is the physics behind the functional parts? How are the magnetic properties measured? Finally, we present, in our view, a list of challenges hindering progress in these technologies.
Synthesis of optically active ene carbamates from chromium carbene complexes : use in palladium(II)-assisted synthesis of relays to (+)-thienamycin

Attempts to prepare optically active chromium carbene complexes containing the oxazolidinone moiety led instead to an efficient and general synthesis of optically active ene carbamates. One of these has been subjected to palladium(II)-assisted carboacylation, and complete control of stereochemistry was observed. This compound was converted to a key relay to (+)-thienamycin in good chemical and very high optical yield
NOVA: QoE-driven optimization of DASH-based video delivery in networks

We consider the problem of optimizing video de- livery for a network supporting video clients streaming stored video. Specifically, we consider the joint optimization of network resource allocation and video quality adaptation. Our objective is to fairly maximize video clients' Quality of Experience (QoE) re- alizing tradeoffs among the mean quality, temporal variability in quality, and fairness, incorporating user preferences on rebuffer- ing and cost of video delivery. We present a simple asymptotically optimal online algorithm, NOVA, to solve the problem. NOVA is asynchronous, and using minimal communication, distributes the tasks of resource allocation to network controller, and quality adaptation to respective video clients. Video quality adaptation in NOVA is also optimal for standalone video clients, and is well suited for use in the DASH framework. Further, NOVA can be extended for use with more general QoE models, networks shared with other traffic loads and networks using fixed/legacy resource allocation.
Structure of a new intermediate Lu2 + xS3 phase

Abstract A new intermediate phase in the Lu-S system, Lu 2 + x S 3 , between the sulfur-rich end of the monosulfide homogeneity range and Lu 2 S 3 was found to be isostructural with Sc 2 S 3 . The structure of Lu 2 + x S 3 is based upon the NaCl-type with a 12 times larger orthorhombic unit cell due to ordering on the vacant lutetium sites, and with ordered vacancies that differentiate it from Sc 2 S 3 .