cssi/SciSciGPT-SciSciNet huggingface dataset:
UV Resonance Raman Studies of the NaClO4 Dependence of Poly-l-lysine Conformation and Hydrogen Exchange Kinetics

We used 204 nm excitation UV Resonance Raman (UVRR) spectroscopy to examine the effects of NaClO4 on the conformation of poly-l-lysine (PLL). The presence of NaClO4 induces the formation of α-helix, π-helix/bulge, and turn conformations. The dependence of the AmIII3 frequency on the peptide Ψ Ramachandran angle allows us to experimentally determine the conformational population distributions and the energy landscape of PLL along the Ramachandran Ψ angle. We also used UVRR to measure the NaClO4 concentration dependence of PLL amide hydrogen exchange kinetics. Exchange rates were determined by fitting the D2O exchanging PLL UVRR AmII′ band time evolution. Hydrogen exchange is slowed at high NaClO4 concentrations. The PLL AmII′ band exchange kinetics at 0.0, 0.2, and 0.35 M NaClO4 can be fit by single exponentials, but the AmII′ band kinetics of PLL at 0.8 M NaClO4 requires a double exponential fit. The exchange rates for the extended conformations were monitored by measuring the Cα–H band kinetics. These ki...
Local privacy and statistical minimax rates

We study the tradeoff between privacy guarantees and the utility of statistical estimators under local differential privacy, where data remains private even from the statistician. We prove bounds on information-theoretic quantities that influence estimation rates as a function of the amount of privacy preserved. Our bounds can be viewed as quantitative data-processing inequalities that, combined with minimax techniques such as Le Cam's and Fano's methods, allow for precise characterization of statistical rates under local privacy constraints.
Imaging of the hypopharynx and cervical esophagus

Cross-sectional imaging with CT and MR imaging plays a crucial role in the evaluationof cancers of the hypopharynx and cervical esophagus. Clinical examination, includingendoscopy, often fails to detect the full extent of this tumor as it has high propensity togrow in submucosal fashion. Detailed description of the cross-sectional anatomy and ofthe tumor growth pattern will aid in the detection and evaluation of the full extent of thelesion. Post-treatment imaging findings are addressed.
Airburst origin of dark shadows on Venus

The Magellan images showed presence of radar-dark shadowlike disks surrounding small impact craters on the Venusian surface, which are also found without craters. This paper examines the hypothesis of Phillips et al. (1991) that the dark shadows formed where shock waves from airbursting impactors met the ground, pulverizing decimeter-scale surface features. A simple analytic model is used successfully to simulate the catastrophic disruption and the deceleration of impactors in a thick atmosphere to reproduce observed Venusian cratering statistics and generate radar-dark disks by the impact of atmospheric shock waves on the surface.
STRUCTURAL PROPERTIES AND MEASUREMENT THEORY OF CERTAIN SETS ADMITTING A CONCATENATION OPERATION

This paper is a contribution to the theory of unidimensional scaling based on a concatenation operation defined for pairs of objects from certain continuous and ordered sets M. Inferences about structural properties of M, such as reflexivity and commutativity of the concatenation operation, are obtained by means of an entirely general non-metric treatment. It is shown that reflexivity holds either throughout or just for a single element and that commutativity of two different elements holds either generally or in no instance. These statements are independent. The study employs concatenation operations defined in an ad hoc way which formally and necessarily satisfy the reflexivity requirement and then also that of commutativity. By this means, the existence and essential uniqueness of scales of M with linear expressions for the various concatenation operations are established. Rules are derived for the way in which the parameters entering into these expressions can change with admissible scale transformations.
Products and factors of Banach function spaces

Given two Banach function spaces we study the pointwise product space E · F, especially for the case that the pointwise product of their unit balls is again convex. We then give conditions on when the pointwise product E · M(E, F) = F, where M(E, F) denotes the space of multiplication operators from E into F.
The second iterate for the Navier–Stokes equation

We consider the iterative resolution scheme for the Navier–Stokes equation, and focus on the second iterate, more precisely on the map from the initial data to the second iterate at a given time t. We investigate boundedness properties of this bilinear operator. This new approach yields very interesting results: a new perspective on Koch–Tataru solutions; a first step towards weak–strong uniqueness for Koch–Tataru solutions; and finally an instability result in B˙∞,q−1, for q>2.
ZrN diffusion barrier in aluminum metallization schemes

Abstract We have studied reactively sputtered ZrN, the most thermally stable of the refractory metal nitrides, for its diffusion barrier properties in aluminum metallization schemes with Rutherford backscattering spectroscopy and transmission electron microscopy (TEM). We find this compound to be very effective against aluminum diffusion up to 500 °C, independently of subtrate temperature during sputtering. The useful temperature range can be extended by 50 °C with proper pre-annealing prior to aluminum deposition. The TEM study of the ZrN grain size as a function of annealing temperature revealed that the grain size does not change significantly upon annealing and that the grains are relatively small even at the highest annealing temperatures (about 300 A at 900 °C). In addition, for annealing temperatures of and below 500 °C large portions of ZrN films were found to be of either amorphous or extremely fine-grain material, thus inhibiting the diffusion along grain boundaries. The presence of Zr3Al4Si5 ternary compound in samples annealed at 600 °C, as determined by X-ray analysis, may suggest that the ZrN barrier fails by decomposition of the film by aluminum.
Direct oxidation of sulfur-containing fuels in a solid oxide fuel cell

Solid-oxide fuel cells with Cu–ceria anodes are shown to provide stable power generation through the direct oxidation of hydrocarbon fuels having sulfur levels similar to that in gasoline and can be regenerated by steam after being poisoned with higher sulfur levels.
Order Progress Information: Improved Dynamic Emergency Ordering Policies

Technologies such as radio-frequency identification and global positioning systems can provide improved real-time tracking information for products and replenishment orders along the supply chain. We call this type of visibility order progress information. In this paper, we investigate how order progress information can be used to improve inventory replenishment decisions. To this end, we examine a retailer facing a stochastic lead time for order fulfillment. We characterize a replenishment policy that is based on the classical (Q, R) policy and that allows for releasing emergency orders in response to the order progress information. We show that the optimal structure of this policy is given by a sequence of threshold values dependent on order progress information. In a numerical study we evaluate the cost savings due to this improved replenishment policy.
Unusual structures and reactivity of mixed metal cluster complexes containing the palladium/platinum tri-t-butylphosphine grouping.

Polynuclear metal carbonyl complexes have a range of applications in chemical research: for example, they can serve as surface models to probe features of heterogeneous catalysis and can perform novel transformations of organic molecules in solutions. Mixed metal complexes can demonstrate bimetallic cooperativity and synergism and can also serve as precursors to multimetallic heterogeneous catalysts that have superior activities and selectivities. This Account describes the results of our recent comprehensive study of the chemistry of mixed metal cluster complexes containing the sterically encumbered M(PBut3), M = Pd or Pt, group. This grouping readily adds to the metal−metal bonds of metal carbonyl cluster complexes and modifies their reactivity. We have prepared new, highly electronically unsaturated mixed metal complexes that exhibit unusually high reactivity toward hydrogen. The platinum atom of the Pt(PBut3) grouping can bond to as many as five metal atoms, and it can interconvert, sometimes rapidly,...
Metal-free oxidative amide formation with N-hydroxysuccinimide and hypervalent iodine reagents

Abstract An oxidative amide formation using N-hydroxysuccinimide and hypervalent iodine reagents was developed. The method enables a wide range of aldehydes and amines to be coupled under mild reaction conditions providing amide in good to excellent yield. The radical species in the reaction mixture was observed for the first time using ESR measurement, and along with other mechanistic investigations, a plausible mechanism of the reaction was proposed.
An assume-guarantee rule for checking simulation

The simulation preorder on state transition systems is widely accepted as a useful notion of refinement, both in its own right and as an efficiently checkable sufficient condition for trace containment. For composite systems, due to the exponential explosion of the state space, there is a need for decomposing a simulation check of the form P ≤sQ, denoting "P is simulated by Q," into simpler simulation checks on the components of P and Q. We present an assume-guarantee rule that enables such a decomposition. To the best of our knowledge, this is the first assume-guarantee rule that applies to a refinement relation different from trace containment. Our rule is circular, and its soundness proof requires induction on trace trees. The proof is constructive: given simulation relations that witness the simulation preorder between corresponding components of P and Q, we provide a procedure for constructing a witness relation for P ≤sQ. We also extend our assume-guarantee rule to account for fairness constraints on transition systems.
Mechanism of the Reaction between Iodate and Iodide Ions in Acid Solutions (Dushman Reaction)

Evidence is given for a stepwise mechanism in the Dushman reaction by using accelerated-flow mixing to measure reaction rates at high [H+] and [I-], where pseudo-first-order rate constants vary from 213 to 6700 s-1. The typical [H+]2 dependence is lowered due to the formation of appreciable [HIO3]. The typical [I-]2 dependence is lowered because I2O2 is a steady-state intermediate. The rate expression is: −d[IO3]T/dt = k1(k2/k-1)KH[H+]2[I-]2[IO3]T/[(1 + KH[H+])(1 + (k2/k-1)[I-])], where k1 = 4.8 × 107 M-2 s-1, k2/k-1 = 2.3 M-1, and KH = 2.5 M-1 at μ = 0.50 M, 25 °C.
Beautiful mirrors at the LHC.

We explore the “Beautiful Mirrors” model, which aims to explain the measured value of AbFB, discrepant at the 2.9σ level. This scenario introduces vector-like quarks which mix with the bottom, subtly affecting its coupling to the Z. The spectrum of the new particles consists of two bottom-like quarks and a charge −4/3 quark, all of which have electroweak interactions with the third generation. We explore the phenomenology and discovery reach for these new particles at the LHC, exploring single mirror quark production modes whose rates are proportional to the same mixing parameters which resolve the AbFB anomaly. We find that for mirror quark masses ≲ 500 GeV, a 14 TeV LHC with 300 fb−1 is required to reasonably establish the scenario and extract the relevant mixing parameters.
Scalable Hybrid Designs for Linear Algebra on Reconfigurable Computing Systems

Recently, high-end reconfigurable computing systems have been built that employ Field Programmable Gate Arrays (FPGAs) as hardware accelerators for general-purpose processors. These systems not only provide new opportunities for high-performance computing, but also pose new challenges to application developers. In this paper, we build a design model for hybrid designs that utilize both the processors and the FPGAs. The model characterizes a reconfigurable computing system using various parameters. Based on the model, we propose a design methodology for hardware/software co-design. The methodology partitions workload between the processors and the FPGAs, maintains load balance in the system, and realizes scalability over multiple nodes. Designs are proposed for several computationally intensive applications: matrix multiplication, matrix factorization and the Floyd-Warshall algorithm for the all-pairs shortest-paths problem. To illustrate our ideas, the proposed hybrid designs are implemented on a Cray XD1. Experimental results show that our designs utilize both the processors and the FPGAs efficiently, and overlap most of the data transfer overheads and network communication costs with the computations. Our designs achieve up to 90% of the total performance of the nodes, and 90% of the performance predicted by the design model. In addition, our designs scale over a large number of nodes.
Corrosion of Galvanized Steel in Soils

Abstract The results of measurements of the corrosion of galvanized steel and of bare steel and zinc as reference materials after exposure to different soil conditions for a maximum of 13 years are reported. The magnitude and progress of corrosion of galvanized steel as determined by weight loss and pitting is interpreted in terms of the environmental conditions to which the specimens were exposed. From analysis of data on the corrosion of galvanized specimens having different weights of coating, minimum coating requirements for different environmental conditions are suggested.
Head-on parallel blade-vortex interaction

An experimental and computational study was carried out to investigate the parallel head-on blade-vortex interaction (BVI) and its noise generation mechanism. A shock tube, with an enlarged test section, was used to generate a compressible starting vortex which interacted with a target airfoil. The dual-pulsed holographic interferometry (DPHI) technique and airfoil surface pressure measurements were employed to obtain quantitative flow data during the BVI. A thin-layer Navier-Stokes code (BV12D), with a high-order upwind-biased scheme and a multizonal grid, was also used to simulate numerically the phenomena occurring in the head-on BVI. The detailed structure of a convecting vortex was studied through independent measurements of density and pressure distributions across the vortex center. Results indicate that, in a strong head-on BVI, the opposite pressure peaks are generated on both sides of the leading edge as the vortex approaches. Then, as soon as the vortex passes by the leading edge, the high-pressure peak suddenly moves toward the low-peak-reducing in magnitude as it moves--simultaneously giving rise to the initial sound wave. In both experiment and computation, it is shown that the viscous effect plays a significant role in head-on BVIs.
Random MAX SAT, random MAX CUT, and their phase transitions

With random inputs, certain decision problems undergo a “phase transition.” We prove similar behavior in an optimization context. Given a conjunctive normal form (CNF) formula F on n variables and with m k-variable clauses, denote by max F the maximum number of clauses satisfiable by a single assignment of the variables. (Thus the decision problem k-SAT is to determine if max F is equal to m.) With the formula F chosen at random, the expectation of max F is trivially bounded by (3/4)m l E max F l m. We prove that for random formulas with m = ⌊cn⌋ clauses: for constants c < 1, E max F is ⌊cn⌋ - Θ(1/n); for large c, it approaches ** equation here ** and in the “window” c = 1 + Θ(n-1/3), it is cn - Θ(1). Our full results are more detailed, but this already shows that the optimization problem MAX 2-SAT undergoes a phase transition just as the 2-SAT decision problem does, and at the same critical value c = 1. Most of our results are established without reference to the analogous propositions for decision 2-SAT, and can be used to reproduce them. We consider “online” versions of MAX 2-SAT, and show that for one version the obvious greedy algorithm is optimal; all other natural questions remain open. We can extend only our simplest MAX 2-SAT results to MAX k-SAT, but we conjecture a “MAX k-SAT limiting function conjecture” analogous to the folklore “satisfiability threshold conjecture,” but open even for k = 2. Neither conjecture immediately implies the other, but it is natural to further conjecture a connection between them. We also prove analogous results for random MAX CUT. © 2004 Wiley Periodicals, Inc. Random Struct. Alg., 2004
On the Near-Infrared Size of Vega

Near-infrared (2.2 μm) long baseline interferometric observations of Vega are presented. The stellar disk of the star has been resolved, and the data have been fitted with a limb-darkened stellar disk of diameter ΘLD = 3.28 ± 0.01 mas. The derived effective temperature is Teff = 9553 ± 111 K. However, the residuals resulting from the stellar disk model appear to be significant and display organized structure. Instrumental artifacts, stellar surface structure, stellar atmosphere structure, and extended emission/scattering from the debris disk are discussed as possible sources of the residuals. While the current data set cannot uniquely determine the origin of the residuals, the debris disk is found to be the most likely source. A simple debris disk model, with 3%-6% of Vega's flux emanating from the disk at r 4 AU, can explain the residuals.
Heparin sensing: Blue-chip binding

Heparin is an anionic polysaccharide that has tremendous clinical importance as an anticoagulant. Several dyes have been developed that can detect heparin, and the latest example — named Mallard Blue — has now been shown to have excellent sensing properties under biologically relevant conditions.
Technological complementarities, demand, and market power

Recent technological changes in many industries have generated numerous complementary technologies. A key implication of complementary technologies is that the demand for related services has tended to change both qualitatively and quantitatively. While the economics literature has examined various aspects, the effects of technological complementarity have not been fully flushed out. Using a simple model, this paper examines the implications of technological complementarity. How have firms' pricing abilities changed with complementary technologies? What implications do complementary technologies have for regulation? Results show that technological complementarity has the potential to increase the market power of firms, possibly increasing prices to unprecedented levels. This holds whether demand elasticity is constant or variable. Policy implications are discussed.
Giant planets at small orbital distances

Using Doppler spectroscopy to detect the reflex motion of the nearby star, 51 Pegasi, Mayor & Queloz (1995) claim to have discovered a giant planet in a 0.05 AU, 4.23 day orbit. They estimate its mass to be in the range 0.5-2 Jupiter masses, but are not able to determine its nature or origin. Including the effects of the severe stellar insolation implied, we extend the theory of giant planets we have recently developed to encompass those at very small orbital distances. Our calculations can be used to help formulate search strategies for luminous planets in tight orbits around other nearby stars. We calculate the radii and luminosities of such giant planets for a variety of compositions (H/He, He, H2O, and olivine), the evolutionary tracks for solar-composition gas giants, and the geometry of the Hayashi forbidden zone in the gas-giant mass regime. We show that such planets are stable and estimate the magnitude of classical Jeans evaporation and of photodissociation and loss due to EUV radiation. In addition, we demonstrate that for the mass range quoted, such planets are well within their Roche lobes. We show that the strong composition dependence of the model radii and the distinctive spectral signatures provide clear diagnostics that might reveal 51 Peg B's nature, should interferometric or adaptive-optics techniques ever succeed in photometrically separating planet from star.
Programming in the medical real-time environment

The Shock Research Unit (SRU) is a specialized clinical research facility developed for the triple purposes of rendering intensive care to seriously ill patients, studying underlying mechanisms of the disease process of circulatory shock, and developing new technologies for evaluating the status and treatment of seriously ill patients.
Nonlinear combination resonances in cantilever composite plates

We experimentally investigated nonlinear combination resonances in two graphite-epoxy cantilever plates having the configurations (90/30/-30/-30/30/90)s and (-75/75/75/-75/75/-75)s. As a first step, we compared the natural frequencies and modes shapes obtained from the finite-element and experimental-modal analyses. The largest difference in the obtained frequencies for both plates was 6%. Then, we transversely excited the plates and obtained force-response and frequency-response curves, which were used to characterize the plate dynamics. We acquired time-domain data for specific input conditions using an A/D card and used them to generate time traces, power spectra, pseudo-state portraits, and Poincare maps. The data were obtained with an accelerometer monitoring the excitation and a laser vibrometer monitoring the plate response. We observed the external combination resonance % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqefm0B1jxALjhiov2D% aebbfv3ySLgzGueE0jxyaibaiGc9yrFr0xXdbba91rFfpec8Eeeu0x% Xdbba9frFj0-OqFfea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs% 0dXdbPYxe9vr0-vr0-vqpWqaaeaabiGaciaacaqabeaadaqaaqGaaO% qaaiabfM6axjabgIKi7kabeM8a3naaBaaaleaacaaIYaaabeaakiab% gUcaRiabeM8a3naaBaaaleaacaaI3aaabeaaaaa!45C9!\[\Omega \approx \omega _2 + \omega _7 \] in the quasi-isotropic plate and the external combination resonance % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqefm0B1jxALjhiov2D% aebbfv3ySLgzGueE0jxyaibaiGc9yrFr0xXdbba91rFfpec8Eeeu0x% Xdbba9frFj0-OqFfea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs% 0dXdbPYxe9vr0-vr0-vqpWqaaeaabiGaciaacaqabeaadaqaaqGaaO% qaaiabfM6axjabgIKi7kaacIcacaaIXaGaai4laiaaikdacaGGPaGa% aiikaiabeM8a3naaBaaaleaacaaIYaaabeaakiabgUcaRiabeM8a3n% aaBaaaleaacaaI1aaabeaakiaacMcaaaa!4AAD!\[\Omega \approx (1/2)(\omega _2 + \omega _5 )\] and the internal combination resonance % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqefm0B1jxALjhiov2D% aebbfv3ySLgzGueE0jxyaibaiGc9yrFr0xXdbba91rFfpec8Eeeu0x% Xdbba9frFj0-OqFfea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs% 0dXdbPYxe9vr0-vr0-vqpWqaaeaabiGaciaacaqabeaadaqaaqGaaO% qaaiabfM6axjabgIKi7kabeM8a3naaBaaaleaacaaI4aaabeaakiab% gIKi7kaacIcacaaIXaGaai4laiaaikdacaGGPaGaaiikaiabeM8a3n% aaBaaaleaacaaIYaaabeaakiabgUcaRiabeM8a3naaBaaaleaacaaI% XaGaaG4maaqabaGccaGGPaaaaa!4FDC!\[\Omega \approx \omega _8 \approx (1/2)(\omega _2 + \omega _{13} )\] in the ±75 plate, where the % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqefm0B1jxALjhiov2D% aebbfv3ySLgzGueE0jxyaibaiGc9yrFr0xXdbba91rFfpec8Eeeu0x% Xdbba9frFj0-OqFfea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs% 0dXdbPYxe9vr0-vr0-vqpWqaaeaabiGaciaacaqabeaadaqaaqGaaO% qaaiabeM8a3naaBaaaleaacaWGPbaabeaaaaa!3F16!\[\omega _i \] are the natural frequencies of the plate and Ω is the excitation frequency. The results show that a low-amplitude high-frequency excitation can produce a high-amplitude low-frequency motion.
Guest editorial agent-based modeling of evolutionary economic systems

A brief overview of agent-based computational economics is given, followed by synopses of the nine contributions included in this special issue. Related work can be accessed at http://www2.econ.iastate.edu/tesfatsi/ace.htm
Ras-Mek-Erk signaling regulates Nf1 heterozygous neointima formation.

Neurofibromatosis type 1 (NF1) results from mutations in the NF1 tumor-suppressor gene, which encodes neurofibromin, a negative regulator of diverse Ras signaling cascades. Arterial stenosis is a nonneoplastic manifestation of NF1 that predisposes some patients to debilitating morbidity and sudden death. Recent murine studies demonstrate that Nf1 heterozygosity (Nf1+/−) in monocytes/macrophages significantly enhances intimal proliferation after arterial injury. However, the downstream Ras effector pathway responsible for this phenotype is unknown. Based on in vitro assays demonstrating enhanced extracellular signal-related kinase (Erk) signaling in Nf1+/− macrophages and vascular smooth muscle cells and in vivo evidence of Erk amplification without alteration of phosphatidylinositol 3-kinase signaling in Nf1+/− neointimas, we tested the hypothesis that Ras-Erk signaling regulates intimal proliferation in a murine model of NF1 arterial stenosis. By using a well-established in vivo model of inflammatory cell migration and standard cell culture, neurofibromin-deficient macrophages demonstrate enhanced sensitivity to growth factor stimulation in vivo and in vitro, which is significantly diminished in the presence of PD0325901, a specific inhibitor of Ras-Erk signaling in phase 2 clinical trials for cancer. After carotid artery injury, Nf1+/− mice demonstrated increased intimal proliferation compared with wild-type mice. Daily administration of PD0325901 significantly reduced Nf1+/− neointima formation to levels of wild-type mice. These studies identify the Ras-Erk pathway in neurofibromin-deficient macrophages as the aberrant pathway responsible for enhanced neointima formation.
Private Financing and Sports Franchise Values: The Case of Major League Baseball

This article examines the impact of receiving a new stadium on team franchise values. The author argues that a new stadium will increase the franchise values of teams regardless of how construction...
A General Model of Functional Constraints on Phenotypic Evolution

Abstract: A general model of the functional constraints on the rate and direction of phenotypic evolution is developed using a decomposition of the Lande‐Arnold model of multivariate phenotypic evolution. The important feature of the model is the F matrix of performance coefficients reflecting the causal relationship between morphophysiological (m‐p) and functional performance traits. The structure of F, which reflects the functional architecture of the organism, constrains the shape of the adaptive landscape and thus the rate and direction of m‐p trait evolution. The rate of m‐p trait evolution is a function of the pattern of coefficients in a row of F. The sums and variances of these rows are related to current concepts of evolvability. The direction of m‐p trait evolution through m‐p trait space is a function of the functional covariances among m‐p traits. The functional covariance between a pair of m‐p traits is a measure of how much the traits function together and is computed as the covariance betwe...
OBSERVATIONAL SIGNATURES OF THE FIRST LUMINOUS OBJECTS

The next generation of astronomical instruments will be able to detect dense pockets of ionized gas created by the first luminous objects. The integrated free-free emission from ionized halos creates a spectral distortion of the cosmic microwave background, greater than the distortion due to the reionized intergalactic medium. Its detection is well within the capabilities of the planned DIMES satellite. Ionized halos may also be imaged directly in free-free emission by the Square Kilometer Array. Bright halos will be detected as discrete sources, while residual unresolved sources can still be detected statistically from temperature fluctuations in maps. Balmer line emission from ionized halos is detectable by the Next Generation Space Telescope and can be used to obtain redshift information. Unlike Lyα, the Hα line does not suffer from resonant scattering by neutral hydrogen and is still observable when the intergalactic medium is not fully reionized. In addition, it is less susceptible to dust extinction. Finally, the kinetic Sunyaev-Zeldovich effect may be used to detect ionized gas at high redshift. Used in concert, these observations will probe ionizing emissivity, gas clumping, and star formation in the early universe.
Delay optimal multichannel opportunistic access

The problem of minimizing queueing delay of opportunistic access of multiple continuous time Markov channels is considered. A new access policy based on myopic sensing and adaptive transmission (MS-AT) is proposed. Under the framework of risk sensitive constrained Markov decision process with effective bandwidth as a measure of queueing delay, it is shown that MS-AT achieves simultaneously throughput and delay optimality. It is shown further that both the effective bandwidth and the throughput of MS-AT are two-segment piece-wise linear functions of the collision constraint (maximum allowable conditional collision probability) with the effective bandwidth and throughput coinciding in the regime of tight collision constraints. Analytical and simulation comparisons are conducted with the myopic sensing and memoryless transmission (MS-MT) policy which is throughput optimal but delay suboptimal in the regime of tight collision constraints.
Cooperative Chiral Order in Polyisocyanates: New Statistical Problems

Polyisocyanates with a random sequence of (R) and (S) pendant groups follow a chiral “majority rule”: the optical activity of the polymers is dominated by whichever enantiomer is in the majority. ...
Autoxidative dimerization of methyl linolenate and its monohydroperoxides, hydroperoxy epidioxides and dihydroperoxides

The structures of dimers and oligomers produced by autoxidation of methyl linolenate and its purified oxidation products were investigated to obtain a better understanding of the mechanism of oxidative deterioration of unsaturated lipids. The dimers were separated by gel permeation chromatography, characterized by molecular weight determinations before and after sodium borohydride reduction, and analyzed by ultraviolet, infrared,1H NMR and fast atom bombardment mass spectrometry. Autoxidation of methyl linolenate at 40 C to peroxide value of 1062 produced 6.8% dimers mainly derived from hydroperoxides, hydroperoxy epidioxides and dihydroperoxides. These dimers were 88% peroxide-linked (C-O-O-C) and 12% ether- (C-O-C) and/or carbon-linked (C-C). Autoxidation of methyl linolenate monohydroperoxides at 40 C produced dimers that were 72% peroxide- and 28% ether/carbon-linked. Thermal decomposition of linolenate hydroperoxides at 150 C gave dimers that were 100% ether/carbon-linked, and catalytic decomposition with ferric chloride-ascorbic acid at room temperature gave dimers with 43% peroxide and 57% ether/carbon linkages. Autoxidation of linolenate hydroperoxy epidioxides at 40 C produced dimers containing hydroperoxy epidioxides, dihydroperoxides and monohydroperoxides joined with peroxide and ether/carbon linkages. Under the same conditions, autoxidation of linolenate dihydroperoxides produced dimers containing dihydroperoxides and hydroperoxy epidioxides joined with peroxide and ether/carbon linkages. These dimers contribute to oxidative and flavor deterioration of polyunsaturated fats in the same way as the hydroperoxide precursors by further decomposition to produce volatile compounds.
Exact half-BPS string-junction solutions in six-dimensional supergravity

We construct SO(2, 1) × SO(3)-invariant half-BPS solutions in six-dimensional (0,4) supergravity with m tensor multiplets. The space-time manifold of each one of these solutions consists of an AdS 2 × S 2 warped over a Riemann surface Σ with boundary. The most general local solution is parametrized by one real harmonic function, and m + 2 holomorphic functions which are subject to a quadratic constraint and a hermitian inequality, both of which are manifestly SO(2, m) invariant. Imposing suitable conditions on these harmonic and holomorphic functions, we construct globally regular supergravity solutions with N distinct AdS 3 × S 3 asymptotic regions and contractible Σ. These solutions have an intricate moduli space, whose dimension equals 2(m + 1)N − m − 2 and matches the counting of three-form charge vectors and un-attracted scalars of the tensor multiplet. Exact explicit formulas for all supergravity fields are obtained in terms of the moduli. Our solutions give the near-horizon geometries for junctions of N self-dual strings in six dimensions, and are holographic duals to CFTs defined on N half-planes which share a common interface line. For m = 5, the solutions lift to quarter-BPS solutions for sixdimensional (4,4) supergravity.
Reduced Order Design of Active Suspension Control

The presence of fast and slow modes in suspension systems is utilized in the design of two reduced-order active suspension-control strategies. The first strategy is obtained by combining the solutions of slow and fast control subproblems. The second strategy is based on a two-level hierarchical control design. In spite of their simplified structure, simulation results indicate that their performance is comparable to that of the full-state-feedback design. >
Fractional-Frequency Rotor Motion Due to Nonsymmetric Clearance Effects

Analysis based on the Jeffcott model is presented to explain 1/2 speed and 1/3 speed whirling motion occurring in rotors which are subject to periodic normal-loose or normal-tight radial stiffness variations. The normal-loose stiffness variation results due to bearing-clearance effects, while normal-tight stiffness variations result from rubbing over a portion of a rotor's orbit. The results demonstrate that 1/2 speed subharmonic motion can be explained as either a linear parametric-excitation phenomenon or as a stable nonlinear subharmonic motion. The 1/3 speed motion is shown to be possible due to the radial stiffness nonlinearity. A linear parametric-excitation analysis demonstrates that during a normal-tight rubbing condition, Coulomb damping significantly widens the potential range of unstable speeds.
Synthesis and chemistry of an iron(III) tetraphenylporphyrin with a covalently-attached phenolate tail

Abstract We report the synthesis of a phenolate-tailed iron(III) tetraphenylporphyrin, 1 . The phenolate ligand is covalently-attached to the porphyrin ring and is coordinated to the iron(III) center. This phenolate ligand increases the rate of oxygen atom transfer to the metal center.
Nusselt Number Behavior on Deep Dimpled Surfaces Within a Channel

Experimental results, measured on a dimpled teat surface placed on one wall of a channel, are given for a ratio of air inlet stagnation temperature to surface temperature of approximately 0.94, and Reynolds numbers R eH from 12,000 to 70,000. These data include friction factors, local Nusselt numbers, spatially-resolved local Nusselt numbers, and globally-averaged Nusselt numbers. The ratio of dimple depth to dimple print diameter δ/D is 0.3, and the ratio of channel height to dimple print diameter is 1.00. These results are compared to measurements from other investigations with different ratios of dimple depth to dimple print diameter δ/D to provide information on the influences of dimple depth. At all Reynolds numbers considered, local and spatially-resolved Nusselt number augmentations increase as dimple depth increases (and all other experimental and geometric parameters are held approximately constant). These are attributed to: (i) increases in the strengths and intensity of vortices and associated secondary flows ejected from the dimples, as well as (ii) increases in the magnitudes of three-dimensional turbulence production and turbulence transport
KINETIC DEUTERIUM ISOTOPE EFFECTS IN TRANSITION METAL HYDRIDE CLUSTERS

Cet article presente des travaux concernant la reactivite d'une serie de complexes trinucleaires carbonyles de l'osmium et du ruthenium: effet isotopique du deuterium au cours de reactions d'echanges de coordinats ou de transfert d'hydrogene, cinetique et mecanisme
Cardiac arrhythmias and aerosol "sniffing".

Aerosol “sniffing,” a variant of glue “sniffing,” involves the deliberate inhalation of aerosol products and propellants. Approximately 65 deaths have been attributed to this practice. They have been predominantly sudden and generally lack conclusive autopsy findings. The cause of death has not been defined in most cases; however, various mechanisms have been postulated. The evidence suggests acute cardiac arrest as a frequent cause. It could result from the sudden onset of ventricular fibrillation due to sensitization of the heart to epinephrine by inhalation of high concentrations of aerosol contents. Experimental investigation revealed that the commonly used aerosol propellants, in high concentrations, are capable of sensitizing the heart to epinephrine resulting in serious cardiac arrhythmias. Therefore, it is concluded that cardiac sensitization is a likely mechanism of death in many of the aerosol-sniffing fatalities.
Is burst activity in cortical slices a representative model for epilepsy

Abstract Neocortical slices including sensory cortex of mouse were used to study cellular and network activity during bicuculline evoked seizure-like activity. The relationship between the activities of single cells and the network was quantified using entropy measures of spike trains. The network shows a large increase in synchronous burst activity during the seizure-like phase. Surprisingly, the individual cells do not seem to follow this pattern of increased synchrony. It is hypothesized that the recruitment of silent units during the seizure onset may explain this paradoxical finding. Our data agrees with recent findings in experimental seizures and intra-operative recordings in humans.
THE CULTURAL ECOLOGY OF THE LOCUST CULT IN TRADITIONAL CHINA

ABSTRACT A geographic study of the locust cult in China, in relation to its ecological and cultural-historical basis, reveals the fact that there is a very high degree of association (a significant correlation coefficient of 0.88) between the frequency of locust infestations and the number of cult temples established. Temples adhering to different cult systems were built in which to perform propitiatory rituals designed to minimize the plagues of insects, thereby alleviating popular anxiety caused by the depredations. In interpreting this cultural-ecological relationship the concept of social equilibrium was applied to the construction of a stress-and-strain model. Culture is viewed as the human coping process against environmental stress, the locust cult temples and the performed rituals being output products serving to restore social equilibrium. Under the eight cult systems concerned with locust rituals, some 870 locust temples have been built within the vicinity of walled cities over the centuries. Th...
α-Haloarylsulfonamides: multiple cyclization pathways to skeletally diverse benzofused sultams

The development of new methods to skeletally diverse sultams based on a central α-halo benzene sulfonamide building block is reported. Several salient features of this building block are utilized in multiple reaction pathways, including the Heck reaction, C- and O-arylation, Sonogashira-Pauson-Khand, Sonogashira-intramolecular hydroamination, lithiative cyclization and domino aza-Michael Heck for the generation of 5-, 6- and 7-membered benzofused bicyclic and tricyclic sultams.
Some problems in data communications between the user and the computer

The ever increasing utilization of computer complexes from remote sources imposes a new dimension to the almost overburdening task of systems design. Remotely accessed systems require a tight integration of communications services and equipment in order to effect a system which is both efficient and responsive.
Laparoscopic and Abdominal Sacral Colpopexies: A Comparative Cohort Study

Objective This study was undertaken to compare laparoscopic and open sacral colpopexies for efficacy and safety. Study design Charts were reviewed for 56 patients who underwent laparoscopic sacral colpopexy and 61 patients who underwent open sacral colpopexy. Demographic and hospital data, complications, and follow-up visits were reviewed. Results Mean follow-up was 13.5 ± 12.1 months and 15.7 ± 18.1months in the laparoscopic and open groups, respectively. Mean operating time was significantly greater in the laparoscopic versus open cohort, 269 ± 65 minutes and 218 ± 60 minutes, respectively ( P P =.04) and hospital stay (1.8 ± 1.0 days vs 4.0 ± 1.8 days; P Conclusion Laparoscopic and open sacral colpopexies have comparable clinical outcomes. Although laparoscopic sacral colpopexy requires longer operating time, hospital stay is significantly decreased.
Skin-Muscle Flap Lower Lid Blepharoplasty

(1989). Skin-Muscle Flap Lower Lid Blepharoplasty. Seminars in Ophthalmology: Vol. 4, No. 4, pp. 238-241.
Dynamics of flexible multi-link robot arms with mass center offset

Abstract A mathematical model for the dynamics of a flexible multi-link manipulator as part of a space-based robotic system has been developed in this paper. Since the system is considered to be in space, the position of the mass center of the system with respect to the center of the main structure will be varied during the system operation. The system mass center is determined by knowledge of the mass centers of the subsystems. The general dynamics of the system are modeled by using the finite element method and the Lagrangian approach, in which the mass center offset of the system is included. It is significant that the system's degrees of freedom will be more coupled to each other when the mass center offset is introduced into the system formulation. The dynamic stability of the system may be verified by applying the linear quadratic regulator techniques through computer simulation. The numerical results show that the system is stable and illustrate the interaction among the subsystems.
Perspectives in imaging using mass spectrometry

Imaging mass spectrometry (MS) allows a remarkable range of measurements including diagnosis of disease state of tissue based on detailed information on its chemical constituents, especially lipids and proteins. The recent emergence of ambient ionization allows imaging in the open environment without sample preparation. In this review, we briefly describe the history of imaging MS highlighting its main techniques and applications. We also demonstrate how the detailed molecular information obtained by imaging MS makes this technique suitable for a range of forensic and clinical applications with the potential to be successfully developed all the way to intra-surgical practice.
The role of selective attention in the acquisition of English tense and lax vowels by native Spanish listeners: comparison of three training methods.

Abstract This study investigates the role of two processes, cue enhancement (learning to attend to acoustic cues which characterize a speech contrast for native listeners) and cue inhibition (learning to ignore cues that do not), in the acquisition of the American English tense and lax ([i] vs. [ɪ]) vowels by native Spanish listeners. This contrast is acoustically distinguished by both vowel spectrum and duration. However, while native English listeners rely primarily on spectrum, inexperienced Spanish listeners tend to rely exclusively on duration. Twenty-nine native Spanish listeners, initially reliant on vowel duration, received either enhancement training, inhibition training, or training with a natural cue distribution. Results demonstrated that reliance on spectrum properties increased over baseline for all three groups. However, inhibitory training was more effective relative to enhancement training and both inhibitory and enhancement training were more effective relative to natural distribution training in decreasing listeners’ attention to duration. These results suggest that phonetic learning may involve two distinct cognitive processes, cue enhancement and cue inhibition, that function to shift selective attention between separable acoustic dimensions. Moreover, cue-specific training (whether enhancing or inhibitory) appears to be more effective for the acquisition of second-language speech contrasts.
Is the NAIRU More Useful in Forecasting Inflation than the Natural Rate of Unemployment

Recent studies have indicated that the terms ‘NAIRU’ (non-accelerating inflation rate of unemployment) and ‘natural rate of unemployment’ are not interchangeable. While NAIRU is an empirical macroeconomic relationship estimated via a Phillips curve, the natural rate is an equilibrium condition in the labour market, reflecting the market's microeconomic features. This study evaluates comparatively the inflation-forecasting power of alternative time-varying estimates of the natural rate of unemployment relative to the NAIRU. The natural rate of unemployment in the USA since the Second World War is estimated. Three alternative methods are utilized: the Kalman filter, a structural determinants approach, and the Hodrick-Prescott filter. The section that follows assesses how each estimator of the natural rate compares with the others – as well as with the NAIRU derived from a Phillips curve – in forecasting inflationary changes in the USA in the second half of the twentieth century. The analysis reveals that th...
Elusive head and neck carcinomas beneath intact mucosa

This study presents 19 patients who had mucosally inapparent carcinomas of the upper aerodigestive tract demonstrated by computed tomography (CT). This group contains subpopulations that were identified both retrospectively and prospectively. During the same period 40 nasopharyngeal, 20 oropharyngeal-tongue base, and over 100 laryngeal and hypopharyngeal carcinomas were studied; all had clinically obvious mucosal components. Nine of our 19 patients had strictly submucosal tumors and a variety of clinical presentations; 5 patients had strictly submucosal recurrence of treated carcinomas and 5 had mucosal lesions which were not identified on examinations by more than one practicing head and neck surgeon. Sixteen of the 19 tumors were confirmed histologically; in 3 others confirmation was by a combination of CT and clinical course. CT can demonstrate the deep extent of aerodigestive tract carcinomas more accurately than physical examination and it can show mucosally inapparent disease. CT should be part of the staging work-up in nearly all upper aerodigestive tract carcinomas and in patients suspected of harboring an unknown primary within this region.
A Study of Integrally Augmented State Feedback Control for an Active Magnetic Bearing Supported Rotor System

State feedback controller designs allow for pole placement in an effective manner, but reduction of static offset is difficult. On the other hand, classical control methodology allows for the increase of system type and the elimination of static offset. An integrally augmented state feedback controller provides the benefits of standard feedback designs while allowing for the elimination of static offsets (through the increase of system type). Static offset is a particular problem with magnetic bearing supported rotor systems, in that gravitational effects, current biasing, and operational loading tend to exacerbate this problem. In order to assess the effectiveness of this technique, an integrally augmented state feedback controller is developed, implemented, and tested for a magnetic bearing supported rotor system. Results for several selected configurations are presented and compared. Some conclusions and recommendations concerning the effectiveness of integrally augmented state feedback controller designs are presented.