cssi/SciSciGPT-SciSciNet huggingface dataset:
Human Immunodeficiency Virus Infection in Pregnancy

The transformation of the human immunodeficiency virus (HIV) epidemic over the last 20 years has been remarkable. With access to appropriate therapies, clinicians can now offer infected women a much improved prognosis as well as a very high likelihood of birthing children who will be HIV uninfected. However, these advances are purchased through the use of complicated, expensive medical regimens (highly active antiretroviral therapy) that are associated with a litany of toxicities and risks. In caring for HIV-infected pregnant women and prescribing these medications, obstetricians must always bear in mind their dual responsibilities, providing optimal care to the mother and reducing the likelihood of mother-to-child transmission of HIV. To accomplish those goals, the physician must first monitor the patient's immunological and virological status including resistance testing. The results of those tests will guide the clinician in choosing when to initiate therapy and in deciding whether to use regimens directed solely at transmission interruption or those that will simultaneously treat the mother's infection. When using highly active antiretroviral therapy, physicians must be cognizant of the pregnancy-specific risks associated with some of the component agents. The core goal of all medical therapy is to bring the patient's viral load to an undetectable level. When that goal is reached, the chance of transmission to the child is minimized, the need for a cesarean delivery is reduced, and the patient's prognosis is optimized. However, if a woman is not pregnant, then the initiation of therapy can be delayed because long-term adherence with medications can be difficult, side effects are not uncommon, and prognosis is not adversely affected so long as the CD4 count and the viral load remain in a reasonable range. None of the advantages cited above can be achieved unless all women have their HIV status determined as early in pregnancy as possible.
Spectral domain second harmonic optical coherence tomography

Optical coherence tomography (OCT) provides micrometer scale structural imaging by coherent detection of light backscattered from a sample. The significance of OCT would be greatly enhanced by the capability to measure molecular specific signals. Observation of fluorescent markers is unfortunately not possible using OCT because fluorescence is not a coherent process. Instead, the methods being researched to extend OCT to include molecular contrast are, amongst others: transient absorption (pump-probe imaging), Coherent Anti-Stokes Raman Scattering (CARS), and second harmonic generation. With any of these techniques, the quality of the images obtained is limited by the conversion efficiency of the nonlinear process, which is inevitably much less than 1 and thus has resulted in low SNR and long acquisition times in previously reported work. Recent publications have demonstrated a sensitivity advantage of 20-30dB for spectral domain (SD) techniques in OCT over conventional time domain acquisition. The increased sensitivity of SD OCT systems stands to benefit the small signal powers observed in molecular contrast OCT. We have constructed a prototype spectral domain second harmonic OCT system utilizing a 130 femtosecond Nd:Glass laser and a pair of custom spectrometers for simultaneous acquisition of the fundamental and second harmonic signals. We report a 10dB increase in sensitivity while imaging 100 times faster than in initial reports of second harmonic OCT using time domain systems.
Stellar Mixing and the Primordial Lithium Abundance

We compare the properties of recent samples of the lithium abundances in halo stars to one another and to the predictions of theoretical models including rotational mixing, and we examine the data for trends with metal abundance. We apply two statistical tests to the data: a Kolomorgorov-Smirnov (K-S) test sensitive to the behavior around the sample median, and Monte Carlo tests of the probability to draw the observed number of outliers from the theoretical distributions. We find from a K-S test that in the absence of any correction for chemical evolution, the Ryan, Norris, & Beers (RNB) sample is fully consistent with mild rotational mixing induced depletion and, therefore, with an initial lithium abundance higher than the observed value. Tests for outliers depend sensitively on the threshold for defining their presence, but we find a 10%-45% probability that the RNB sample is drawn from the rotationally mixed models with a 0.2 dex median depletion with lower probabilities corresponding to higher depletion factors. Including or excluding the one upper limit in the sample changes the absolute probabilities but does not affect the overall conclusions. When chemical evolution trends (Li/H vs. Fe/H) are included in our analysis we find that the dispersion in the RNB sample is not explained by chemical evolution; the inferred bounds on lithium depletion from rotational mixing are similar to those derived from models without chemical evolution. Finally, we explore the differences between the RNB sample and other halo star data sets. We find that differences in the equivalent width measurements are primarily responsible for different observational conclusions concerning the lithium dispersion in halo stars. The different data sets are all consistent with mild stellar depletion, but the systematic errors arising from different observational data sets are a major component of the error budget and need to be addressed. The implications for cosmology are discussed. We find that the standard big bang nucleosynthesis predicted lithium abundance that corresponds to the deuterium abundance inferred from observations of high-redshift, low-metallicity QSO absorbers requires halo star lithium depletion in an amount consistent with that from our models of rotational mixing but inconsistent with no depletion.
Electrical Properties of 0.4 cm Long Single-Walled Carbon Nanotubes

Centimeter scale aligned carbon nanotube arrays are grown from nanoparticle/metal catalyst pads. We find the nanotubes grow both “with” and “against the wind”. A metal underlayer provides in situ electrical contact to these long nanotubes with no post growth processing needed. Using the electrically contacted nanotubes, we study electrical transport of 0.4 cm long nanotubes. The source−drain I−V curves are quantitatively described by a classical, diffusive model. Our measurements show that the outstanding transport properties of nanotubes can be extended to the cm scale and can open the door to large scale integrated nanotube circuits with macroscopic dimensions.
Friction induced surface activity of some simple organic chlorides and hydrocarbons with iron.

Sliding friction studies were conducted on an iron surface with exposure of that surface to various hydrocarbons and organic chlorides. The hydrocarbons included ethane, ethylene, ethyl chloride, methyl chloride and vinyl chloride. Auger cylindrical-mirror analysis was used to follow interactions of the hydrocarbon and organic chlorides with the iron surface. Results with vinyl chloride indicate friction-induced surface reactivity, adsorption to surface oxides, friction sensitivity to concentration and polymerization. Variation in the loads employed influence adsorption and, accordingly, friction. Unlike results with ethyl and vinyl chloride, friction-induced surface reactivity was not observed with ethane and ethylene. Presented at the 28th ASLE Annual Meeting in Chicago, Illinoir, April 30–May 3, 1973
SU(2) reduction of six-dimensional (1,0) supergravity

We obtain a gauged supergravity theory in three dimensions with eight real supersymmetries by means of a Scherk–Schwarz reduction of pure N=(1,0) supergravity in six dimensions on the SU(2) group manifold. The SU(2) Yang–Mills fields in the model propagate, since they have an ordinary kinetic term in addition to Chern–Simons couplings. The other propagating degrees of freedom consist of a dilaton, five scalars which parameterise the coset SL(3,R)/SO(3), three vector fields in the adjoint of SU(2), and twelve spin-12 fermions. The model admits an AdS3 vacuum solution. We also show how a charged black hole solution can be obtained, by performing a dimensional reduction of the rotating self-dual string of six-dimensional (1,0) supergravity.
Fundamental Groups of Spaces with Bakry–Emery Ricci Tensor Bounded Below

We first extend Cheeger–Colding’s Almost Splitting Theorem (Ann Math 144:189–237, 1996) to smooth metric measure spaces. Arguments utilizing this extension show that if a smooth metric measure space has almost nonnegative Bakry–Emery Ricci curvature and a lower bound on volume, then its fundamental group is almost abelian. Second, if the smooth metric measure space has Bakry–Emery Ricci curvature bounded from below then the number of generators of the fundamental group is uniformly bounded. These results are extensions of theorems which hold for Riemannian manifolds with Ricci curvature bounded from below. The first result extends a result of Yun (Proc Amer Math Soc 125:1517–1522, 1997), while the second extends a result of Kapovitch and Wilking (Structure of fundamental groups of manifolds with Ricci curvature bounded below, 2011).
Causes and Seasonality of Momentum Profits

With Januaries (a month in which lagged “losers” typically outperform lagged “winners”) excluded, the average monthly return to a momentum strategy for U.S. stocks was found to be 59 bps for non-quarter-ending months but 310 bps for quarter-ending months. The pattern was stronger for stocks with high levels of institutional trading and was particularly strong in December. The results suggest that window dressing by institutional investors and tax-loss selling contribute to stock return momentum. Investors using a momentum strategy should focus on quarter-ending months and securities with high levels of institutional trading.
Parallel matrix multiplication on a linear array with a reconfigurable pipelined bus system

The known fast sequential algorithms for multiplying two N/spl times/N matrices (over an arbitrary ring) have time complexity O(N/sup /spl alpha//), where 2</spl alpha/<3. The current best value of /spl alpha/ is less than 2.3755. We show that, for all 1/spl les/p/spl les/N/sup /spl alpha//, multiplying two N/spl times/N matrices can be performed on a p-processor linear array with a reconfigurable pipelined bus system (LARPBS) in O(N/sub m//P+(N/sup 2//p/sup 2//spl alpha//)log p) time. This is currently the fastest parallelization of the best known sequential matrix multiplication algorithm on a distributed memory parallel system. In particular, for all 1/spl les/p/spl les/N/sup 2.3755/, multiplying two N/spl times/N matrices can be performed on a p-processor LARPBS in O(N/sup 2.3755//p+(N/sup 2/)/p/sup 0.8419/log p) time and linear speedup can be achieved for p as large as O(N/sup 2.3755//(log N)/sup 6.3262/). Furthermore, multiplying two N/spl times/N matrices can be performed on an LARPBS with O(N/sup /spl alpha//) processors in O(log N) time. This compares favorably with the performance on a PRAM.
Experimental and Numerical Investigation of Losses in Low-Pressure Turbine Blade Rows

Experimental data and numerical simulations of low-pressure turbines have shown that unsteady blade row interactions and separation can have a significant impact on the turbine efficiency. Measured turbine efficiencies at takeoff can be as much as two points higher than those at cruise conditions. Several recent studies have revealed that the performance of low-pressure turbine blades is a strong function of the Reynolds number. In the current investigation, experiments and simulations have been performed to study the behavior of a low-pressure turbine blade at several Reynolds numbers. Both the predicted and experimental results indicate increased cascade losses as the Reynolds number is reduced to the values associated with aircraft cruise conditions. In addition, both sets of data show that tripping the boundary layer helps reduce the losses at lower Reynolds numbers. Overall, the predicted aerodynamic and performance results exhibit fair agreement with experimental data.
Utilization of Recycled Carpet Waste Fibers for Reinforcement of Concrete and Soil

Abstract The use of recycled fibers from textile waste for concrete and soil reinforcement is a very attractive approach, with such benefits as performance enhancement, low-cost raw materials, and reduced needs for landfilling. This article discusses the general advantages of fiber reinforcement and reviews some studies on the use of carpet waste fibers for concrete and soil reinforcement. A study on recycled carpet waste fibers for fiber-reinforced concrete (FRC) showed a significant toughness increase and reduced shrinkage. It included two concrete mix designs and a wide range of fiber dosage rates, from 0.07 to 2.0 vol.%. A research program on fiber-reinforced soil is underway for fiber characterization, analysis of the engineering properties of the fiber-soil systems, and field trials. A significant improvement in soil behavior under the triaxial loading condition was observed.
A new efficient waveform simulation method for RLC interconnect via amplitude and phase approximation

In this paper we use a segmented Chebyshev orthogonal polynomial expansion approach to approximate amplitude and phase response for RLC interconnect simulation. This method has been shown to be efficient in reducing frequency sampling point number or expansion order. Experiments also show that the number of sampling points is not necessarily dependent on the interconnect circuit size, which makes possible large network simulation. Additionally, because of the smoothing-effect of the atan function in evaluation, the phase response, which has major impact on the transient edge of output response, can be easily approximated. Experiments show the proposed simulation approach achieves 30-50 times speed-up over spice3f4.
An empirical analysis of changes in credit rating properties: Timeliness, accuracy and volatility

Abstract In recent years, credit rating agencies have faced increased regulatory pressure and investor criticism for their ratings’ lack of timeliness. This study investigates whether and how rating agencies respond to such pressure and criticism. We find that the rating agencies not only improve rating timeliness, but also increase rating accuracy and reduce rating volatility. Our findings support the criticism that, in the past, rating agencies did not avail themselves of the best rating methodologies/efforts possible. When their market power is threatened by the possibility of increased regulatory intervention and/or reputation concerns, rating agencies respond by improving their credit analysis.
Improving Interactions Between Teachers and Young Children with Problem Behavior: A Strengths-Based Approach

Young children who exhibit problem behavior are at-risk for a host of negative developmental outcomes. Early intervention at multiple ecological levels is crucial to interrupt what can be a detrimental transactional cycle between children and their caregivers, including their teachers. In this article we promote a strengths-based approach to improving teacher-child interactions, which may serve as a protective factor for children with early-onset problem behavior in early childhood classrooms. Specifically, we describe how increases in targeted teacher behaviors can foster the desirable behavior of young children by capitalizing on skills the children already possess while enhancing those skills necessary for social competence and pre-academic success.
The Coulomb anomaly in strongly disordered films

Abstract Electron tunneling measurements of the Coulomb anomaly in the density of states in strongly disordered quench condensed granular films are presented. The strength of this anomaly grows with increasing sheet resistance, R N , at low R N but saturates at high R N . We suggest that the granular morphology of these films is responsible for the saturation.
Asian equity markets: growth, opportunities, and challenges

Asian equity markets have grown significantly in size since the early 1990s, driven by strong international investor inflows, growing regional financial integration, capital account liberalization, and structural improvements to markets. The development of equity markets provides a more diversified set of channels for financial intermediation to support growth, thus bolstering medium-term financial stability. At the same time, as highlighted by the May–June 2006 market corrections, the increasing role of stock markets potentially changes the nature of macroeconomic and financial stability risks, as well as the policy requirements for dealing with these risks.
A new parallel method for molecular dynamics simulation of macromolecular systems

Short-range molecular dynamics simulations of molecular systems are commonly parallelized by replicated-data methods, in which each processor stores a copy of all atom positions. This enables computation of bonded 2-, 3-, and 4-body forces within the molecular topology to be partitioned among processors straightforwardly. A drawback to such methods is that the interprocessor communication scales as N (the number of atoms) independent of P (the number of processors). Thus, their parallel efficiency falls off rapidly when large numbers of processors are used. In this article a new parallel method for simulating macromolecular or small-molecule systems is presented, called force-decomposition. Its memory and communication costs scale as N/√P, allowing larger problems to be run faster on greater numbers of processors. Like replicated-data techniques, and in contrast to spatial-decomposition approaches, the new method can be simply load balanced and performs well even for irregular simulation geometries. The implementation of the algorithm in a prototypical macromolecular simulation code ParBond is also discussed. On a 1024-processor Intel Paragon, ParBond runs a standard benchmark simulation of solvated myoglobin with a parallel efficiency of 61% and at 40 times the speed of a vectorized version of CHARMM running on a single Cray Y-MP processor. © 1996 by John Wiley & Sons, Inc.
Diastereoselective Synthesis of γ- and δ-Lactams from Imines and Sulfone-Substituted Anhydrides

Sulfone-substituted γ- and δ-lactams have been prepared in a single step with high diastereoselectivity. Sulfonylglutaric anhydrides produce intermediates that readily decarboxylate to provide δ-lactams with high diastereoselectivity. Substituents at the 3- or 4-position of the glutaric anhydride induce high levels of stereocontrol. Sulfonylsuccinic anhydrides produce intermediate carboxylic acids that can be trapped as methyl esters or allowed to decarboxylate under mild conditions. This method has been applied to a short synthesis of the pyrrolizidine alkaloid (±)-isoretronecanol.
New Directions in Intercalation Research

Abstract Since the start of this decade (the 1990's), intercalation has become a more important tool for modifying the structure and properties of host materials, both because of the important new systems to which intercalation has been applied and because of the new science and technology that has been made possible by these discoveries. Recently, the intercalation of fullerenes by alkali metals have demonstrated intercalation in zero-dimensional systems. The observation of relatively high Tc superconductivity in certain alkali metal intercalated fullerenes has attracted much attention. Even more recent is the introduction of guest species into one-dimensional carbon nanotubules. Intercalation has also been used to gain insights into the properties of high Tc cuprates. A review is given here of recent advances in the intercalation of GICs and of new materials systems with particular relevance to the implication of this work on more traditional areas of intercalation physics.
Continuous noninvasive cardiac output as estimated from the pulse contour curve

We developed a noninvasive computer-based system for estimating continuous cardiac output by a modified pulse contour method using a finger pressure waveform. The method requires no individual patient calibration or baseline cardiac output. First, we calibrated the system in a "learn" group of 20 patients. The computer-based cardiac output was then compared with thermodilution cardiac output in 27 patients undergoing coronary artery bypass surgery. A total of 94 cardiac outputs were performed (three averaged per determination) at four predetermined time periods: preinduction, postinduction, prebypass, and postbypass. During determination of each thermodilution cardiac output, the pulse wave data were simultaneously recorded on cassette tape. The patients had cardiac outputs ranging from 2.9 to 6.4 L/min. The correlation coefficient was 0.75. The average thermodilution cardiac output was 4.50 (+/- 0.83 SD) L/min, while the cardiac output derived from the finger pressure wave was 4.48 (+/- 0.7 SD) L/min (95% confidence interval [CI] of difference, 0-3.2%). The mean difference between the two methods was 0.02 (+/- 0.55 SD) L/min. The 95% CI for the bias was 0.0001 to 0.036 L/min. The 95% CI for the lower limit of agreement was -1.12 to -1.06 L/min; the upper limit for the 95% CI was 1.09 to 1.16 L/min. The program demonstrated that information about cardiac output can be obtained by using the Finapres device (Ohmeda, Boulder, CO). The cardiac output values obtained by this continuous noninvasive technique were within +/- 20% of the simultaneous thermodilution values 87% of the time. This was true over the narrow range of cardiac outputs (2.9 to 6.4 L/min) and wide range of heart rates (45 to 140 beats/min).
Competition law and the millennium round

To advance the debate about whether competition should be on the agenda of the World Trade Organization, this paper identifies the key point at which trade law and competition law meet: the blockage of market access by anti-competitive restraints. At this open-market intersection, there is a synergy to be captured by combining principles of free trade and principles of free competition. The author proposes a simple architecture, with a choice of law principle for seamlessly incorporating into the WTO a discipline against private market access restraints. The author cautions against indiscriminately raising antitrust issues to an international level and against doing so under a trade law banner. For the world competition issues that are not trade issues, a free-standing World Competition Forum is proposed, interactive where appropriate with the WTO. Copyright 1999 by Oxford University Press.
Sublattice magnetizations in lithium ferrite as a function of temperature

We have made neutron diffraction measurements of the intensities of the (111) and (331) reflections from a single crystal of ordered lithium ferrite, LiFe5O8. These intensities are proportional to the value of the function [2MA(T)+2MB(T)]2/[2MA(0)+2MB(0)]2, where MA(T) and MB(T) are the magnetizations of the ions on tetrahedral and octahedral sites, respectively. Combining this intensity data with the net magnetization measurements of Rado and Folen, we have determined the individual magnetizations of the A and B sublattices. A comparison of these sublattice magnetizations with calculations based on molecular field theory, using parameters determined from the magnetic measurements, revealed that the actual values of these magnetizations at temperatures greater than about 0.4 Tc are significantly higher than the values predicted by the theory. Furthermore, a systematic investigation of the effects of varying the ratios of the A‐A and B‐B molecular field parameters to the A‐B parameter revealed that, althou...
In-water 3D integral imaging

The 3D Synthetic Aperture Integral Imaging (SAII) technique is adapted for in-water applications. The traditional SAII system is adapted for in-water use by compensating for the known changes in beam propagation due to the differing indices of refraction of air and water. An imaging situation is discusses where the SAII system is placed in water along with objects. Laboratory based experimental results are presented and demonstrate the ability of the in-water SAII system to image through heavy occlusion. This paper serves as an overview of work completed on in-water integral imaging.
Implications of a minimal SO(10) Higgs structure

Abstract A minimal SO(10) Higgs structure involving a single adjoint field along with spinors, vectors and singlets has been shown to break the SO(10) gauge symmetry to the standard model while stabilizing the F-flat directions and solving the doublet-triplet splitting problem naturally. With this minimal set of Higgs fields, we show how to construct quark and lepton mass matrices which explain well the many features of the observed spectrum, including the Georgi-Jarlskog mass relations. A large νμ − ντ mixing angle results naturally as observed in the atmospheric neutrino data. A particular model relying on a family symmetry has been constructed which realizes the desired mass matrices.
A FLAMINGOS Deep Near-Infrared Imaging Survey of the Rosette Complex. I. Identification and Distribution of the Embedded Population

We present the results of a deep near-infrared imaging survey of the Rosette complex made with FLAMINGOS at the 2.1 m telescope at Kitt Peak National Observatory. We studied the distribution of young embedded sources using a variation of the nearest neighbor method applied to a carefully selected sample of near-infrared excess (NIRX) stars that trace the latest episode of star formation in the complex. Our analysis confirmed the existence of seven clusters previously detected in the molecular cloud, and identified four more clusters across the complex. We determined that 60% of the young stars in the complex and 86% of the stars within the molecular cloud are contained in clusters, implying that the majority of stars in the Rosette formed in embedded clusters. Also, half of the young embedded population is contained in four clusters that coincide with the central core of the cloud, where the main interaction with the H II region is taking place. We compare the sizes, infrared excess fractions, and average extinction toward individual clusters to investigate their early evolution and expansion. In particular, the size and degree of central condensation within the clusters appear to be related to the degree of infrared excess and mean extinction in a way that suggests that the clusters form as compact entities and then quickly expand after formation. We found that the average infrared excess fraction of clusters increases as a function of distance from NGC 2244, implying a temporal sequence of star formation across the complex. This sequence appears to be primordial, possibly resulting from the formation and evolution of the molecular cloud and not from the interaction with the H II region. Instead, the main influence of the H II region could be to enhance or inhibit the underlying pattern of star formation in the cloud.
NONPERTURBATIVE INSTABILITY OF BLACK HOLES IN QUANTUM GRAVITY

The final stage of a black hole evaporation due to the Hawking effect is studied. One finds that, including the effects of quantum gravity, a black hole does not evaporate completely losing its energy steadily to a flux of created particles, but rather decays via a change in topology into an asymptotically flat space and an object which is a closed Friedmann Universe. This process is a genuine non-perturbative effect of quantum gravity and becomes the dominant “channel” of a black hole decay for black holes with masses slightly larger than the Planck mass Mp=1019 GeV. We calculate the decay rate of a Schwarzchild black hole with the mass M and discuss other decay “channels” by topology change. An explicit instanton mediating the decay is constructed by matching the Schwarzschild and the “wormhole” Friedmann instantons on the minimal sphere which is a Euclidean section of the event horizon. We show, as an example, that the decay process is mediated in the semi-classical approximation by the gravitational-a...
Design, synthesis and structure–Activity relationships of novel imidazolo[1,2-a]pyrimid-5-ones as potent GnRH receptor antagonists

Abstract SAR studies of lead GnRH receptor antagonists 2a and 2b reported earlier resulted in the discovery of compound 10b which showed much higher potency ( K i =4.6 nM, compared with 2b , K i =230 nM) in which the 7-position of the imidazolo[1,2- a ]pyrimidone core was substituted with a methyl group, and the ester at the 6-position was replaced by the 3-methoxyphenyl group.
Oscillatory behavior of the rate of escape through an unstable limit cycle

Suppose a two-dimensional dynamical system has a stable attractor that is surrounded by an unstable limit cycle. If the system is additively perturbed by white noise, the rate of escape through the limit cycle will fall off exponentially as the noise strength tends to zero. By analyzing the associated Fokker-Planck equation we show that in general the weak-noise escape rate is non-Arrhenius: it includes a factor that is periodic in the logarithm of the noise strength. The presence of this slowly oscillating factor is due to the nonequilibrium potential of the system being nondifferentiable at the limit cycle. We point out the implications for the weak-noise limit of stochastic resonance models. {copyright} {ital 1996 The American Physical Society.}
Total Synthesis of the Enantiomer of the Furanocembrane Rubifolide.

The total synthesis of 57, the enantiomer of the marine furanocembrane rubifolide (3), is described starting from (S)-(-)-perillyl alcohol (5). The successful route proceeded by oxidative cleavage of 5 to ester aldehyde 30 which was protected, reduced, and homologated to the acetylene 34, the left-hand segment of the synthetic target. Addition to the right-hand aldehyde 39 afforded alcohol 40. The carbonate derivative 41 was converted to the allenylstannane aldehyde 44, which cyclized upon treatment with BF(3).OEt(2). Oxidation with the Dess-Martin periodinane reagent followed by treatment with Et(3)N yielded allenone 45. Allenone 45 cyclized to furan 46 in the presence of catalytic AgNO(3) on silica gel. Brief exposure to p-TsOH effected elimination of the OMOM ether, affording the diastereomeric (Z)-vinylfuran carbonates 47 and 49. Saponification of the former led to alcohol 48, which was converted to the final product by sequential treatment with (CF(3)CO)(2)O, then Pd(PPh(3))(4) and CO in THF-H(2)O, and then AgNO(3) on silica gel. The resulting product, 57, was identical to natural rubifolide on the basis of spectral comparison. The optical rotation was equal and opposite in sign to that of the natural material. A second, but unsuccessful approach is also described.
Solution plans and interactive problem solving

Abstract The concept of a ‘solution plan’ is used to characterize the structure of interactive systems in which the user guides the solution process. A formalism for describing and analyzing solution plan structures is presented. The formalism can be used to define the role of the user in an interactive system. The solution plan approach to interaction is particularly applicable to problems which have an obvious graphical representation. An interactive graphics system for solving a class of routing problems is described. Suggestions for the application of the approach to other problems are included.
Why should disclosure rules subsidize informed traders

Abstract This article justifies the existence of disclosure provisions as part of the securities laws. Securities prices may deviate from the securities' underlying values due to “irrationalities.” Market efficiency (i.e., the accuracy of securities' prices) materializes through the trading of investors who observe and attempt to profit from these inefficiencies. The danger of false prices deters the corrective trading of these “informed traders”. This article argues that disclosure rules provide them with costless information, essentially subsidizing their activity. The cost of this subsidy is borne by the corporation, i.e., all shareholders, of which informed traders are only a fraction. Long-term shareholders would not subsidize efficiency absent disclosure rules because, they do not trade, and they do not reap the benefits of accurate prices. This subsidy fosters short-term uninformed shareholdings and, thus, increases trading volume and capital market liquidity.
Brunhes Epoch Geomagnetic Secular Variation on Marion Island: Contribution to Evidence for a Long-Term Regional Geomagnetic Secular Variation Maximum

A paleomagnetic study of 30 lavas from Marion Island, situated on the Indian-Atlantic ridge yields a value for Brunhes epoch secular variation with confidence limits so broad that no distinction can be made with present geomagnetic field behavior. When combined with similar results from the nearby Crozet Islands, however, data for over 100 separate lavas become available for analysis, facilitating an estimate of regional secular variation with narrow confidence limits. The result, which suggests that Brunhes epoch geomagnetic secular variation in this region was (at the 95 percent confidence level) higher than at present, could be explained if the present secular variation maximum south of South Africa persisted during at least the past half million years. It is concluded that values of Brunhes epoch geomagnetic secular variation may depend not only on latitude, experimental methods, and coverage of the geological interval involved, but also on proximity to long term isoporic foci. Incidental results for the survey include detection of excursions attributable to non-dipole behavior in some instances, and possible dipole tilting in other cases.
Routing-as-a-service (RaaS): a framework for tenant-directed route control in data center

In a multi-tenant data center environment, the current paradigm for route control customization involves a labor-intensive ticketing process where tenants submit route control requests to the landlord. This results in tight coupling between tenants and the landlord, extensive human resource deployment, and long ticket resolution time. We propose Routing-as-a-Service (RaaS), a framework for tenant-directed route control in data centers. We show that RaaS-based implementation provides a route control platform where multiple tenants can perform route control independently with little administrative involvement, and the landlord can set the overall network policies. RaaS-based solutions can run on commercial off-the-shelf (COTS) hardware and leverage existing technologies, so it can be implemented in existing networks without major infrastructural overhaul. We present the design of RaaS, introduce its components, and evaluate a prototype based on RaaS.
Isoquinoline-based chiral monodentate N-heterocyclic carbenes.

C 1-symmetric isoquinoline-based chiral diaminocarbene ligands (MIQ) have been developed to block three quadrants of the metal coordination sphere, complementing C2-symmetric biisoquinoline-based ligands (BIQ). MIQ-Cu complexes catalyzed conjugate borylation of various α,β-unsaturated amides in good yields (82–99%) and enantioselectivities (75–87% ee).
The Preparation of 2-(2-Oxo-2-Phenylethyl) Benzoic Acids from Dilithiated Ortho-Toluic Acid.

Abstract ortho-Toluic acid was dimetalated with excess lithium diisopropylamide, and the resulting intermediate was condensed with a variety of aromatic esters to afford new substituted 2-(2-oxo-2-phenylethyl)benzoic acids (ortho-phenacylbenzoic acids).
Probabilistic progressive buckling of trusses

A three-bay, space, cantilever truss is probabilistically evaluated to describe progressive buckling and truss collapse in view of the numerous uncertainties associated with the structural, material, and load variables (primitive variables) that describe the truss. Initially, the truss is deterministically analyzed for member forces, and member(s) in which the axial force exceeds the Euler buckling load are identified. These member(s) are then discretized with several intermediate nodes and a probabilistic buckling analysis is performed on the truss to obtain its probabilistic buckling loads and respective mode shapes. Furthermore, sensitivities associated with the uncertainties in the primitive variables are investigated, margin of safety values for the truss are determined, and truss end node displacements are noted. These steps are repeated by sequentially removing the buckled member(s) until onset of truss collapse is reached. Results show that this procedure yields an optimum truss configuration for a given loading and for a specified reliability.
The Continuing Saga of the Marine Polyether Biotoxins

Brevetoxin B emerged from the sea and into the laboratories of Nakanishi and Clardy who, in 1981, reported its magnificent and unprecedented structure. With its ladder-like fused polyether molecular architecture, potent toxicity, and fascinating voltage-sensitive sodium channel-based mechanism of action, it immediately captured the imagination of chemists around the world. Their synthetic escapades resulted in numerous new synthetic methods and strategies for the construction of cyclic ethers, and culminated in several impressive total syntheses of this imposing molecule and some of its equally challenging siblings that followed. Indeed, many more brevetoxin-type marine polyethers have been reported since 1981 with maitotoxin being not only the most complex and most toxic of the class, but also the largest non-polymeric natural product known to date. In this article, we begin with a brief history of these biotoxins and the phenomena that led to their isolation and highlight their biological properties and mechanism of action. We then review the chemical synthesis endeavors so far published in this long running saga, placing particular emphasis on the new synthetic methods and technologies discovered, developed and applied to their total syntheses over the last few decades. Finally, we conclude with a discussion of the, as yet unfinished, story of maitotoxin, and project into the future of this fascinating area of research.
High Mass Ratio Contact Binaries - Recent Evolution Into Contact

Recent theories of the origin and evolution of contact binaries suggest that the two stars evolve into contact through angular momentum loss (AML; Mochnacki 1981, Vilhu 1982). When in contact, the system then evolves toward smaller mass ratio through mass transfer from the secondary to the primary component (Webbink 1976, Rahunen and Vilhu 1982). Most contact binaries have mass ratios of 0.3 to 0.5.
Using an Electrostatic Accelerator to Determine the Stereochemical Structures of Molecular Ions

Traditional experimental techniques (e.g. studies on photon absorption or emission) for determining the stereochemical structures of neutral molecules are extremely difficult to apply to molecular ions because of problems in obtaining a sufficient spatial density of the ions to be studied. Recent high-resolution measurements on the energy and angle distributions of the fragments produced when fast (MeV) molecular-ion beams from an electrostatic accelerator dissociate ("Coulomb explode") in thin foils and in gases, offer promising possibilities for deducing the stereochemical structures of the molecular ions constituting the incident beams. Bond lengths have been determined in this way for several diatomic projectiles (H2+, HeH+, CH+, NH+, OH+, N2+, O2+, etc.) with an accuracy of ~0.01 A. H3+ has been demonstrated (for the first time) to be equilateral triangular and the interproton distance measured. Measurements on single fragments from CO2+, N2O+, C3H3+, and CHn+ have revealed the gross structures of the projectiles. An apparatus has recently been constructed at Argonne to permit precise measurements on fragments in coincidence. The apparatus has been tested on a known structure (OH2+) The O-H bond length was found to be 1.0 ± 0.04 A and the H-O-H bond angle was measured as 110 ± 2°. These values are in excellent agreement with those found in optical experiments (0.999 A and 110.5°). This "Coulomb explosion" technique can be expected to be refined in accuracy and to be extended to a wide range of molecular ions whose structures are inaccessible by other means.
Quality monitoring of continuous flow processes

Abstract In this research, existing quality control techniques for monitoring continuous flow processes are evaluated. Autocorrelation is a common characteristic of continuous flow process data, and the effect of the autocorrelated data is modelled as an autoregressive time series model of order one or two. The process is simulated on the computer for various process parameters, and the effectiveness of a given statistical process control technique for detecting known process disturbances is evaluated by determining the average run length. Due to the limitations of existing statistical process control techniques, a recursive Kalman filter is proposed as an alternative for eliminating the autocorrelation from the process data. The modelled manufacturing process, the computer simulation results, and the recursive Kalman filter are summarized in this paper.
Constraints from extended supersymmetry in quantum mechanics

Abstract We consider quantum mechanical gauge theories with sixteen supersymmetries. The Hamiltonians or Lagrangians characterizing these theories can contain higher derivative terms. In the operator approach, we show that the free theory is essentially the unique abelian theory with up to four derivatives in the following sense: any small deformation of the free theory, which preserves the supersymmetries, can be gauged away by a unitary conjugation. We also present a method for deriving constraints on terms appearing in an effective Lagrangian. We apply this method to the effective Lagrangian describing the dynamics of two well-separated clusters of D0-branes. As a result, we prove a non-renormalization theorem for the ν 4 interaction.
Topics in Gradient Maintenance and Salt Recycling in an Operational Solar Pond

Since 1986, the 3355 m{sup 2} salt gradient solar pond facility in El Paso, Texas, has operated with a temperature difference between the upper and lower zones of 55 to 75{degrees}C while delivering industrial process heat, grid-connected electrical power, and thermal energy for the experimental production of desalted water. Because the El Paso solar pond is an inland facility, it is necessary to recycle the salt in a sustainable salt management system. A method that uses the main pond surface for initial brine concentration and short-term storage was developed after it became evident that the original evaporation pond system was undersized. This paper examines the method for brine concentration and storage, the effects of a brine storage zone on pond operation, and the installation of an enhanced evaporation net system and an automatic scanning injection system. A short description of the performance history and current status of the project is also included.
The complexity of propositional linear temporal logics

The complexity of satisfiability and determination of truth in a particular finite structure are considered for different propositional linear temporal logics. It is shown that these problems are NP-complete for the logic with F and are PSPACE-complete for the logics with F, X, with U, with U, S, X operators and for the extended logic with regular operators given by Wolper.
Duality and monodromy reducibility of A -hypergeometric systems

We study hypergeometric systems H A (β) in the sense of Gelfand, Kapranov and Zelevinsky under two aspects: the structure of their holonomically dual system, and reducibility of their rank module. We prove in the first part that rank-jumping parameters always correspond to reducible systems. We show further that the property of being reducible is “invariant modulo the lattice”, and obtain as a special instance a theorem of Alicia Dickenstein and Timur Sadykov on reducibility of Mellin systems. In the second part we study a conjecture of Nobuki Takayama which states that the holonomic dual of H A (β) is of the form H A (β′) for suitable β′. We prove the conjecture for all matrices A and generic parameter β, exhibit an example that shows that in general the conjecture cannot hold, and present a refined version of the conjecture. Questions on both duality and reducibility have been quite difficult to answer with classical methods. This paper may be seen as an example of the usefulness, and scope of applications, of the homological tools for A-hypergeometric systems developed in Matusevich et al. (J. Amer. Math. Soc. 18:919–941, 2005)
Unlocking Knowledge Transfer Potential: Knowledge Demonstrability and Superordinate Social Identity

This study presents a conceptual model of when and how knowledge demonstrability and superordinate social identity impact the likelihood that organizations capitalize on their knowledge resources. To test the model, an experimental methodology was used in which a member transfers from one group to another, transmitting knowledge in the form of a production routine. As predicted, work groups unlocked the knowledge transfer potential arising from personnel movement more often when they shared a superordinate identity than when they did not share such an identity, and this identity effect was moderated by knowledge demonstrability. When knowledge was less demonstrable with concealed merits, it was more likely to transfer between groups that shared a superordinate identity, compared to groups that did not share such an identity. By contrast, when knowledge was more demonstrable with apparent merits, it was as likely to transfer between groups that shared a superordinate identity compared to groups that did not share such an identity. As predicted, superordinate identity induced knowledge consideration, the focusing of group attention on determining the value of another's knowledge. Mediated moderation analyses revealed that this process underlies knowledge transfer. Superordinate social identity induced thorough knowledge consideration, which was more important for recognizing the value of knowledge when its merits were concealed rather than apparent. Because the merits of many organizational routines and practices are concealed and superordinate identity appears to be a key to unlocking the knowledge transfer potential of less demonstrable knowledge, this study has important implications for managing knowledge resources.