cssi/SciSciGPT-SciSciNet huggingface dataset:
Sigma stellation: a design strategy for electron boxes.

The carbon−fluorine antibonding (σ*) orbitals in a fluorocarbon cage are directed toward a central, common point. If the cage is not too large or too small, then the σ* orbitals will overlap at that point. An added electron can occupy the resulting molecular orbital, suggesting that cage perfluorocarbons will have large electron affinities. This prediction is supported by electronic structure calculations of all of the fluorinated derivatives of tetrahedrane, cyclopropane, and cubane and of some other fluorinated cage and ring compounds. Perfluorododecahedrane (C20F20) is predicted to have an electron affinity of about 3.4 eV, which is equal to that of the fluorine atom. A few speculative extensions and applications are suggested.
Efficient Hydrosilylation of Carbonyl Compounds with the Simple Amide Catalyst [Fe{N(SiMe3)2}2]

Fe(NTms2)2 represents a novel cost-effective, environmentally benign catalyst for the hydrosilylation of carbonyl compounds at room temperature.
6,6′-Dihydroxy terpyridine: a proton-responsive bifunctional ligand and its application in catalytic transfer hydrogenation of ketones

The ligand 6,6′-dihydroxy terpyridine (dhtp) is presented as a bifunctional ligand capable of directing proton transfer events with metal-coordinated substrates. Solid-state analysis of a Ru(II)-dhtp complex reveals directed hydrogen-bonding interactions of the hydroxyl groups of dhtp with a Ru-bound chloride ligand. The utility of dhtp was demonstrated by chemoselective transfer hydrogenation of ketones.
The effect of the detector response time on bolometric cosmic microwave background anisotropy experiments

We analyze the effects of the detector response time on bolometric measurements of the anisotropy of the cosmic microwave background (CMB). We quantify the effect in terms of a single dimensionless parameter L defined as the ratio between the time the beam sweeps its own size and the bolometer response time. As L decreases below ∼ 2.5 the point source response of the experiment becomes elongated. We introduce a window function matrix based on the timestream data to assess the effects of the elongated beam. We find that the values of the window function matrix elements decrease slowly as a function L. Our analysis and results apply to other cases of beam asymmetry. For the High Frequency Instrument on board the Planck Surveyor satellite we show that for a broad range of L the ability of the experiment to extract the cosmological parameters is not degraded. Our analysis enhances the flexibility in tuning the design parameters of CMB anisotropy experiments.
Unified cost effective next-generation passive optical network and IEEE 802.16m network architecture

This paper presents the key features of the emerging Next Generation Passive Optical Network (NG-PON) and IEEE 802.16m based Mobile Worldwide Interoperability for Microwave Access (WiMAX) networks to build a unified cost effective next generation hybrid Fiber-Wireless network. NG converged-access solutions can meet the demand for cost, mobility, bandwidth, reliability, security, and flexibility. NG-PON and 4th Generation (4G) Mobile WiMAX unified architecture enables differentiated bandwidth allocation to end users and can provide more network range and capacity at reduced operational cost. The concept of hybrid optical network unit and advanced base station (ONU-ABS) simplifies the network architecture and can save some installation and operational costs.
Adaptive minimum variance methods for direct blind multichannel equalization

Abstract In this paper, stochastic gradient and RLS-based methods are presented for designing direct adaptive equalizers. Self-recovering solutions are obtained by minimizing the equalizer’s output variance subject to appropriate constraints. The constraints are chosen to guarantee no desired signal cancellation and are also jointlyand adaptively optimized to improve performance. The resulting algorithm may be interpreted as an optimal version of earlier linear prediction-based approaches. It is shown that the algorithm enjoys global convergence. Moreover, the constraint parameters converge to the channel parameters at high SNR. Comparisons with other blind and trained methods are presented.
Perspective on “Benzynes, dehydroconjugated molecules, and the interaction of orbitals separated by a number of intervening σ bonds”

This paper provides an overview of the title paper by Hoffmann, Imamura, and Hehre, and the impact this paper has had on the area of long-range intramolecular interactions. The author has made extensive use of the through-bond/through-space decomposition of Hoffmann et al. in his work on long-range interaction in bichromopheric molecules. In particular he has applied these ideas in analyzing electron transmission spectra of such molecules.
Geometric complexity theory: an introduction for geometers

This article is survey of recent developments in, and a tutorial on, the approach to \(\mathbf{P}\) v. \(\mathbf{N\mathbf P}\) and related questions called geometric complexity theory (GCT). It is written to be accessible to graduate students. Numerous open questions in algebraic geometry and representation theory relevant for GCT are presented.
A New Technique to Determine Horizontal and Vertical Permeabilities from the Time-Delayed Response of a Vertical Interference Test

To determine the permeabilities from a vertical interference test, earlier investigators proposed correlations or type curves based on point source solutions or partially penetrated well solutions. However, it is impossible for these correlations or type curves to cover all possible scenarios in the real world. In more recent years, people use regression analysis to simultaneously match the pressure responses at the source interval and the observation point. With regression analysis, we face the problem of non-unique solutions. Sometimes, estimated permeability could be outside a reasonable range when analyzing noisy data from real tests. In this paper, a new technique is presented to estimate horizontal and vertical permeabilities from the time-delayed response in a wireline vertical interference test. In a vertical test, a pressure drawdown test period is followed by a pressure buildup test period. Because of the delay in response, the pressure at the observation probe continues to drop for some time while the pressure at the source interval is being built up. The maximum pressure drop at the observation probe with regard to the maximum pressure drop in the source interval is time-delayed. Using this time delay and the maximum pressure drop at the observation probe, vertical and horizontal permeabilities can be estimated. A novel numerical scheme is used. The new technique is compared with the previous methods, and it shows its superiority in accuracy. In addition, it can be used in different test configurations. Application issues in real testing conditions are discussed. Finally, two field tests are analyzed using this technique, while an earlier effort to analyze the tests using a conventional method was not successful due to poor data quality.
Efficient profile matching for large scale Webcasting

This paper presents an efficient method of matching diverse data against user profiles in large-scale Webcasting systems. Its design and implementation are described in the context of the Grand Central Station (GCS) project at IBM Almaden Research Center. Initial performance evaluation indicates the ability of GCS profile matching to scale up and achieve strong performance via dynamic adaptation.
Relationship between thermoelasticity and reinforcement in elastomers: Silica filled silicone elastomers

Increases in modulus, tensile strength, and swelling caused by reinforcing silicone rubber with silica filler were correlated with the thermoelastic parameter, fe/f. A new semiempirical equation of state, containing a generalized front factor, was derived to explain the experimental results. While the retractive force in pure gum elastomers is largely entropic in origin, reinforcement in silicone rubber-silica systems appears to arise by greatly augmenting the deformational free energy change stored in energetic modes.
Regression Analysis of Count Data

Students in both social and natural sciences often seek regression methods to explain the frequency of events, such as visits to a doctor, auto accidents, or new patents awarded. This book, now in its second edition, provides the most comprehensive and up-to-date account of models and methods to interpret such data. The authors combine theory and practice to make sophisticated methods of analysis accessible to researchers and practitioners working with widely different types of data and software in areas such as applied statistics, econometrics, marketing, operations research, actuarial studies, demography, biostatistics and quantitative social sciences. The new material includes new theoretical topics, an updated and expanded treatment of cross-section models, coverage of bootstrap-based and simulation-based inference, expanded treatment of time series, multivariate and panel data, expanded treatment of endogenous regressors, coverage of quantile count regression, and a new chapter on Bayesian methods.
Biogenetic interrelationships of ergot alkaloids

Abstract The biogenetic interconversions of clavine alkaloids have been studied by the use of clavine-C14 and clavine-H3 alkaloids labeled biosynthetically in saprophytic culture, and four different ergot strains in saprophytic cultures. Agroclavine was shown to be oxidized irreversibly to elymoclavine. The attack appears to be directly on the methyl group. Agroclavine, but not elymoclavine, was shown to be converted irreversibly to the following clavine alkaloids: festuclavine, pyroclavine, and setoclavine. Elymoclavine was shown to be the precursor of lysergol, isolysergol, penniclavine, and isopenniclavine. These conversion reactions are irreversible. Only three clavine alkaloids were found to be metabolized in ergot strain 47 A, viz., agroclavine, elymoclavine, and lysergene, all of which have a double bond in position 8. Chanoclavine was shown not to be a precursor of the clavine alkaloids. Evidences indicate that it was not a breakdown product of agroclavine or of any other clavine alkaloid derived from agroclavine. Lysergene was shown to be converted to lysergol, isolysergol, penniclavine, and isopenniclavine. No evidence was found suggesting that lysergene is a normal intermediate in the biosynthesis of these compounds from elymoclavine. Each stereoisomer was found to be biosynthesized as such and not to be the result of a chemical or biochemical isomerization process.
Do many-particle neutrino interactions cause a novel coherent effect?

We investigate whether coherent flavor conversion of neutrinos in a neutrino background is substantially modified by many-body effects, with respect to the conventional one-particle effective description. We study the evolution of a system of interacting neutrino plane waves in a box. Using its equivalence to a system of spins, we determine the character of its behavior completely analytically. We find that, if the neutrinos are initially in flavor eigenstates, no coherent flavor conversion is realized, in agreement with the effective one-particle description. This result does not depend on the size of the neutrino wavepackets and therefore has a general character. The validity of the several important applications of the one-particle formalism is thus confirmed.
Computational Engineering of the Stability and Optical Gaps of SiC Quantum Dots

We have carried out an ab initio computational study of SiC nanoparticles with diameters between 1 and 3 nm. Our calculations show that surface composition and termination play a dominant role in determining the optical gaps and thermodynamic stability of these nanoparticles. In particular, we find that the optical gap of cubic SiC dots can be engineered as a function of their size and surface composition to obtain absorption and emission from the UV to the green. Our results suggest that SiC nanoparticles may be used to build new materials for semiconductor-based UV light sources.
Advertising, economic development, and global warming

Abstract Advertising is tied to global warming through an endogenous growth model. The model allows for the possibility that the environment can become a source rather than a sink for greenhouse gases. Optimal control analysis of the model shows that a feasible steady state is possible for which the environment remains a sink, and identifies a sufficient condition for such to be the case. Comparative-static analysis shows that, for sufficiently small values of steady-state anthropogenic greenhouse gas concentration, global surface temperature and advertising in steady state are negative functions of parameters that measure the damaging effects of global warming.
Risk, Optimal Government Finance and Monetary Policies in a Growing Economy

Optimal tax and monetary policies in a stochastic monetary growth model are investigated. Our findings are of three general types. First, both capital income taxes and monetary growth are shown to influence the economy through effective risk-adjusted measures, expressed as a linear function of their respective means and variances. Second, two stochastic neutrality results relating to money and bonds, the two nominal assets in the economy, are identified. Third, optimal policy rules relating to taxes, bond finance and money creation are characterized. An essential component of optimal financial policy is a risk-adjusted balanced budget.
Fixed block configuration group divisible designs with block size six

We present constructions and results about GDDs with two groups and block size six. We study those GDDs in which each block has configuration (s,t), that is in which each block has exactly s points from one of the two groups and t points from the other. We show the necessary conditions are sufficient for the existence of GDD(n,2,6;@l"1,@l"2)s with fixed block configuration (3,3). For configuration (1,5), we give minimal or near-minimal index examples for all group sizes n>=5 except n=10,15,160, or 190. For configuration (2,4), we provide constructions for several families of GDD(n,2,6;@l"1,@l"2)s.
Foreign aid and fiscal behavior in a bounded rationality model: Different policy regimes

We examine how the source of foreign aid affects the composition of the recipient government's spending. Does the source of aid – bilateral or multilateral – influence recipient policy-makers' choice between development and nondevelopment expenditure? We depart from previous literature by introducing strong asymmetries in policy-makers' preferences. With the financial constraints set by foreign aid and domestic revenues, this formalization allows us to model and estimate the fiscal behavior of government policy-makers in the presence of foreign aid.
Ion pair aggregates and reactions; experiment and theory

Two methods have been developed for determining the aggregation equilibrium constants of lithium enolates based on the change in UV-vis spectrum with concentration and the effect of aggregation on proton-transfer equilibria. Dimers and tetramers are common. Substitution α to the carbonyl group generally reduces aggregation. Kinetic studies show that SN2 alkylations generally occur with the monomers, even in the presence of large amounts of aggregate. The qualitative chemistry is well modeled by ab initio computations at the HF level with modest basis sets; in these studies solvation is modeled by a combination of coordination of lithium cation with an ether oxygen and the electrostatic interaction of the resulting dipoles and quadrupoles with the solvent dielectric continuum.
A Fast Derandomization Scheme and Its Applications

This paper presents a fast derandomization scheme for the PROFIT/COST problem. Through the applications of this scheme the time complexity of $O(\log^2 n \log \log n)$ for the $\Delta+1$ vertex-coloring problem using $O((m+n)/\log \log n)$ processors on the concurrent read exclusive write parallel random-access machine (CREW PRAM), the time complexity of $O( \log^{2.5} n)$ for the maximal independent set problem using $O((m+n)/\log^{1.5} n )$ processors on the CREW PRAM and the time complexity of $O(\log^{2.5} n)$ for the maximal matching problem using $O((m+n)/\log^{0.5} n)$ processors on the exclusive read exclusive write (EREW) PRAM are shown.
Minimax Filtering Regret via Relations Between Information and Estimation

We investigate the problem of continuous-time causal estimation under a minimax criterion. Let X T = (X t ,0 ≤ t ≤ T) be governed by the probability law P θ from a class of possible laws indexed by θ ∈ A, and Y T be the noise corrupted observations of X T available to the estimator. We characterize the estimator minimizing the worst case regret, where regret is the difference between the causal estimation loss of the estimator and that of the optimum estimator. One of the main contributions of this paper is characterizing the minimax estimator, showing that it is in fact a Bayesian estimator. We then relate minimax regret to the channel capacity when the channel is either Gaussian or Poisson. In this case, we characterize the minimax regret and the minimax estimator more explicitly. If we further assume that the uncertainty set consists of deterministic signals, the worst case regret is exactly equal to the corresponding channel capacity, namely the maximal mutual information attainable across the channel among all possible distributions on the uncertainty set of signals. The corresponding minimax estimator is the Bayesian estimator assuming the capacity-achieving prior. Using this relation, we also show that the capacity achieving prior coincides with the least favorable input. In addition, we show that this minimax estimator is not only minimizing the worst case regret, but also essentially minimizing regret for most of the other sources in the uncertainty set. We present a couple of examples for the construction of a minimax filter via an approximation of the associated capacity achieving distribution.
Assessing the benefits of design for recycling for plastics in electronics: A case study of computer enclosures

Abstract With the emergence of extended producer responsibility regulations for electronic devices, it is becoming increasingly important for electronics manufacturers to apply design for recycling (DFR) methods in the design of plastic enclosures. This paper presents an analytical framework for quantifying the environmental and economic benefits of DFR for plastic computer enclosures during the design process, using straightforward metrics that can be aligned with corporate environmental and financial performance goals. The analytical framework is demonstrated via a case study of a generic desktop computer enclosure design, which is recycled using a typical US “take-back” system for plastics from waste electronics. The case study illustrates how the analytical framework can be used by the enclosure designer to quantify the environmental and economic benefits of two important DFR strategies: choosing high-value resins and minimizing enclosure disassembly time. Uncertainty analysis is performed to quantify the uncertainty surrounding economic conditions in the future when the enclosure is ultimately recycled.
Vascular tube formation on matrix metalloproteinase-1-damaged collagen

Connective tissue damage and angiogenesis are both important features of tumour growth and invasion. Here, we show that endothelial cells maintained on a three-dimensional lattice of intact polymerised collagen formed a monolayer of cells with a cobblestone morphology. When the collagen was exposed to organ culture fluid from human basal cell tumours of the skin (containing a high level of active matrix metalloproteinase-1 (MMP-1)), degradation of the collagen matrix occurred. The major degradation products were the $3over 4$- and $1over 4$-sized fragments known to result from the action of MMP-1 on type I collagen. When endothelial cells were maintained on the partially degraded collagen, the cells organised into a network of vascular tubes. Pretreatment of the organ culture fluid with either tissue inhibitor of metalloproteinase-1 (TIMP-1) or neutralising antibody to MMP-1 prevented degradation of the collagen lattice and concomitantly inhibited endothelial cell organisation into the vascular network. Purified (activated) MMP-1 duplicated the effects of skin organ culture fluid, but other enzymes including MMP-9 (gelatinase B), elastase or trypsin failed to produce measurable fragments from intact collagen and also failed to promote vascular tube formation. Together, these studies suggest that damage to the collagenous matrix is itself an important inducer of new vessel formation.
Exploring the Subnational Dimension of Income Inequality: An Analysis of the Relationship Between Inequality and Electoral Turnout in the Developed Countries

This paper offers an exploratory analysis of the subnational dimension of income inequality, using data from the Luxembourg Income Study. The paper undertakes two basic tasks. First, it describes the results of calculations on household-level income data that produce indicators of intra- and inter-household inequality for 191 regions in 12 developed countries for the late 1980s and early 1990s, and for 149 regions in 8 countries for the mid-1990s. Second, the paper demonstrates the value of regional analysis by reexamining the relationship between electoral turnout and income inequality, an important substantive issue which has heretofore been explored almost entirely at the national or individual level but upon which regional-level analysis can shed valuable light.
Urologic applications of botox

Botulinum toxin (BTX), a neurotoxin produced by the gram-positive, rod-shaped anaerobic bacterium Clostridium botulinum, was isolated in 1897 by Belgian scientist Professor Pierre Emile van Ermengem. BTX acts by blocking the release of acetylcholine at the neuromuscular junction. As a result of this chemodenervation, a temporary flaccid paralysis ensues. Different medical disciplines have taken advantage of this temporary paralysis to treat muscular hypercontraction. BTX was first approved by the US Food and Drug Administration in 1989 for use in patients with strabismus and blepharospasm. Since then, BTX has been used to treat a number of different neuromuscular disorders. Although not approved by the US Food and Drug Administration, BTX has been used successfully in urology to treat neurogenic and non-neurogenic detrusor overactivity, detrusor-sphincter dyssynergia, motor and sensory urge, and chronic pain syndromes.
Direct anonymous attestation

This paper describes the direct anonymous attestation scheme (DAA). This scheme was adopted by the Trusted Computing Group (TCG) as the method for remote authentication of a hardware module, called Trusted Platform Module (TPM), while preserving the privacy of the user of the platform that contains the module. DAA can be seen as a group signature without the feature that a signature can be opened, i.e., the anonymity is not revocable. Moreover, DAA allows for pseudonyms, i.e., for each signature a user (in agreement with the recipient of the signature) can decide whether or not the signature should be linkable to another signature. DAA furthermore allows for detection of "known" keys: if the DAA secret keys are extracted from a TPM and published, a verifier can detect that a signature was produced using these secret keys. The scheme is provably secure in the random oracle model under the strong RSA and the decisional Diffie-Hellman assumption.
Load balancing without regret in the bulletin board model

We analyze the performance of protocols for load balancing in distributed systems based on no-regret algorithms from online learning theory. These protocols treat load balancing as a repeated game and apply algorithms whose average performance over time is guaranteed to match or exceed the average performance of the best strategy in hindsight. Our approach captures two major aspects of distributed systems. First, in our setting of atomic load balancing, every single process can have a significant impact on the performance and behavior of the system. Furthermore, although in distributed systems participants can query the current state of the system they cannot reliably predict the effect of their actions on it. We address this issue by considering load balancing games in the bulletin board model, where players can find out the delay on all machines, but do not have information on what their experienced delay would have been if they had selected another machine. We show that under these more realistic assumptions, if all players use the well-known multiplicative weights algorithm, then the quality of the resulting solution is exponentially better than the worst correlated equilibrium, and almost as good as that of the worst Nash. These tighter bounds are derived from analyzing the dynamics of a multi-agent learning system.
α-Lithio trimethylsilylmethyl lithium carbonate as methanol dianion synthon: a one-pot synthesis of α-hydroxy ketones

Abstract 1-Trimethylsilylmethanol is used via its lithiated lithium carbonate in a one-pot procedure to hydroxymethylate esters, dimethylamides, acid chlorides and nitriles to give the corresponding hydroxymethyl carbonyl compounds in the synthetic conversion RCOX → RCOCH2OH.
Charging the superconformal index

The superconformal index is an important invariant of superconformal field theories. In this note we refine the superconformal index by inserting the charge conjugation operator C. We construct a matrix integral for this charged index for N = 4 SYM with SU(N) gauge group. The key ingredient for the construction is a “charged character”, which reduces to Tr(C) for singlet representations of the gauge group. For each irreducible real SU(N ) representation, we conjecture that this charged character is equal to the standard character for a corresponding representation of SO(N + 1) or SP(N − 1), for N even or odd respectively. The matrix integral for the charged index passes tests for small N and for N → ∞. Like the ordinary superconformal index, for N = 4 SYM the charged index is independent of N in the large-N limit.
Geographical deregulation and competition in U.S. banking markets

The effects of geographical deregulation on competition in banking markets is examined. Using a model that develops an index of competition as proposed by Bresnahan and applied to banking markets by Shaffer, the empirical evidence suggests that geographical deregulation has not had a significant impact on competition. The limited effects of geographical deregulation on competition is consistent with other evidence presented, suggesting that banking markets were already highly competitive. In those states where a significant effect was observed, geographical deregulation increased the degree of competition in some states but had the opposite effect in others.
The Chandra X-ray Observatory calibration database (CalDB): building, planning, and improving

The calibration database implemented for the Chandra X-ray Observatory is the most detailed and extensive CalDB of its kind to date. Built according to the NASA High Energy Astrophysics Science Archive Research Center (HEASARC) CalDB prescription, the Chandra CalDB provides indexed, selectable calibration data for detector responses, mirror effective areas, grating efficiencies, instrument geometries, default source aim points, CCD characteristics, and quantum efficiencies, among many others. The combined index comprises approximately 500 entries. A standard FTOOLS parametric interface allows users and tools to access the index. Unique dataset selection requires certain input calibration parameters such as mission, instrument, detector, UTC date and time, and certain ranged parameter values. The goals of the HEASARC CalDB design are (1) to separate software upgrades from calibration upgrades, (2) to allow multi-mission use of analysis software (for missions with a compliant CalDB) and (3) to facilitate the use of multiple software packages for the same data. While we have been able to meet the multivariate needs of Chandra with the current CalDB implementation from HEASARC, certain requirements and desirable enhancements have been identified that raise the prospect of a developmental rewrite of the CalDB system. The explicit goal is to meet Chandra's specific needs better, but such upgrades may also provide significant advantages to CalDB planning for future missions. In particular we believe we will introduce important features aiding in the development of mission-independent analysis software. We report our current plans and progress.
Optimization methods for passive damper placement and tuning

The effectiveness of viscous elements in introducing damping in a structure is a function of several variables, including their number, their location in the structure, and their physical properties. This paper addresses the questions of the placement of these elements and the selection of their physical parameters via optimization techniques.
Tit for tat: Foundations of preferences for reciprocity in strategic settings

Abstract This paper assumes that in addition to conventional preferences over outcomes, players in a strategic environment have preferences over strategies. It provides conditions under which a player's preferences over strategies can be represented as a weighted average of the utility from outcomes of the individual and his opponents. The weight one player places on an opponent's utility from outcomes depends on the players’ joint behavior. In this way, the framework is rich enough to describe the behavior of individuals who repay kindness with kindness and meanness with meanness. The paper identifies restrictions that the theory places on rational behavior.
The Quest for Primordial Stellar Populations and the James Webb Space Telescope

The NASA/ESA/CSA James Webb Space Telescope ( JWST ) will be the successor to the Hubble Space Telescope and may be launched as early as mid-2011. The key scientific goals for JWST are discovering and understanding the formation of the first stars and galaxies, the evolution of galaxies and the production of elements by stars, and the process of star and planet formation. Within this context, we discuss the expected properties of the first stellar generations in the Universe. We find that it is possible to discern truly primordial populations from the next generation of stars by measuring the metallicity of high-z star forming objects. The very low background of JWST will enable it to image and study first-light sources at very high redshifts, whereas its relatively small collecting area limits its capability in obtaining spectra of z∼10-15 first-light sources to either the bright end of their luminosity function or to strongly lensed sources. With a suitable investment of observing time JWST will be able to detect individual Population III supernovae, thus identifying the very first stars that formed in the Universe.
SECRETION OF ALPHA AND BETA SUBUNITS OF TSH BY THE ANTERIOR PITUITARY

We have attempted to determine whether blood concentrations of the alpha chains of TSH arise by direct pituitary secretion of alpha chain or by degradation of the intact hormone after secretion. Highly purified human TSH was administered by infusion to euthyroid volunteers; blood TSH concentrations were raised to 36 muu/ml. After TSH infusion, circulating blood alpha chain concentrations did not change. The same volunteers received an infusion of TRH which stimulated pituitary secretion of TSH, raising blood concentrations to 15 muu/ml in one series of subjects and to 23 muu/ml in a second series. After TRH, blood concentrations of alpha chain increased from undetectable to over 400 pg/ml. We conclude that alpha subunits of TSH are directly secreted by the pituitary gland and are not formed by degradation of intact TSH in the peripheral circulation.
Green management and the nature of pollution prevention innovation

Management systems have a strong impact on the level of innovation and on production operations. Understanding this impact sheds light on how firms function. This article examines the relationship between a firm’s approach to environmental management and the nature of the pollution prevention activities or practices that it undertakes. We differentiate pollution prevention activities according to (i) four functional characteristics and (ii) visibility to consumers. We find that the application of the total quality management (TQM) approaches on pollution prevention has a stronger effect for practices that involve procedural changes or are of a customized nature. These are indeed the type of practices where one would expect TQM to have a disproportionate impact in decision-making effectiveness. There seems to be no corresponding effect on the adoption of practices that are visible to consumers. Our results corroborate the notion that a well-designed management system can help stimulate innovation, but only...
Scaling the Near-Field Centerline Mixing Behavior of Axisymmetric Turbulent Jets

Detailed measurements of the centerline mixing behavior in the near field of variable-density jets were performed. Real-time measurements ofjet fluid concentration for a propane jet and a methane jet issuing into still air were made utilizing Rayleigh light scattering. The initial conditions were those of fully developed pipe flow, and testing was done for flow rates yielding Reynolds numbers in the range of 3.3 x 10 3 -2.3 X 10 4 , based on the average discharge velocity, exit diameter, and initial fluid properties. Centerline decay characteristics in the near field exhibited a downstream shift with increasing Reynolds number, which was attributed to the initial velocity distribution at the jet exit. Investigation of the mean and turbulent characteristics of the initial velocity distribution yielded a proposed near-field scale variable that effectively captured this dependence on Reynolds number. Collapse of the near-field centerline velocity and concentration distributions was achieved using the proposed scaling
Parsing algorithms with backtrack

Two classes of restricted top-down parsing algorithms modeling “recursive descent” are considered. We show that the smaller class recognizes all deterministic context free languages, and that both classes can be simulated in linear time on a random access machine. Certain generalizations of these parsing algorithms are shown equivalent to the larger class. Finally, it is shown that the larger class has the property that loops and other “failures” can always be eliminated.
Can multipath mitigate power law delays?: effects of parallelism on tail performance

Parallelism has often been used to improve the reliability and efficiency of a variety of different engineering systems. In this paper, we quantify the efficiency of parallelism in systems that are prone to failures and exhibit power law processing durations. We focus on the context of transmitting a data unit in communication networks, where parallelism can be achieved by multipath transmission (e.g., multipath routing). We investigate two types of transmission schemes: redundant and split transmission techniques. We find that the power-law transmission delay phenomenon still persists with multipath transmission. In particular, we show that when the transmission delays of each path are characterized by the same power law, redundant multipath transmission can only result in a constant factor performance gain, while order gains are possible when the delays are light tailed. We further compare the performance of redundant transmission and split transmission, and show that there is no clear winner. Depending on the packet size distribution properties and the manner in which splitting is performed, one scheme results in greater performance over the other. Specifically, split transmission is effective in mitigating power law delays if the absolute value of the logarithm of the packet size probability tail is regularly varying with positive index, and becomes ineffective if the above quantity is slowly varying. Based on our analysis, we develop an optimal split transmission strategy, and show that this strategy always outperforms redundant transmission.
A Hardy-Ramanujan-Rademacher-type formula for (r, s)-regular partitions

Let p r,s (n) denote the number of partitions of a positive integer n into parts containing no multiples of r or s, where r>1 and s>1 are square-free, relatively prime integers. We use classical methods to derive a Hardy–Ramanujan–Rademacher-type infinite series for p r,s (n).
Shaping Operations to Attack Robust Terror Networks

Security organizations often attempt to disrupt terror or insurgent networks by targeting "high value targets" (HVT's). However, there have been numerous examples that illustrate how such networks are able to quickly re-generate leadership after such an operation. Here, we introduce the notion of a "shaping" operation in which the terrorist network is first targeted for the purpose of reducing its leadership re-generation ability before targeting HVT's. We look to conduct shaping by maximizing the network-wide degree centrality through node removal. We formally define this problem and prove solving it is NP-Complete. We introduce a mixed integer-linear program that solves this problem exactly as well as a greedy heuristic for more practical use. We implement the greedy heuristic and found in examining five real-world terrorist networks that removing only 12% of nodes can increase the network-wide centrality between 17% and 45%.
Near-field pressure fluctuations of an elliptic jet

Author(s): Gutmark, E; Ho, CM | Abstract: The near-field pressure fluctuations of an elliptic jet were experimentally investigated in this work. The characteristics of the fluctuating pressure were found to be only slightly different in the two planes containing the major and minor axes. A spectral analysis of the pressure fluctuations was performed and its relation to the velocity perturbations generated by vortex merging was examined. © 1985 American Institute of Aeronautics and Astronautics, Inc., All rights reserved.
Charge injection properties of iridium oxide films produced on Ti-6Al-4V alloy substrates by ion beam mixing techniques

Abstract The charge injection capabilities of iridium oxide films, as produced on Ti-6Al-4V alloy substrates by ion-beam mixing techniques, were investigated. Iridium oxide is a valence change oxide, and therefore has high values of charge injection density upon voltage cycling in electrolytes. Because of this property, iridium oxide films are useful as working elements in neural prostheses. Iridium films of three thicknesses, produced by sputter deposition followed by ion beam mixing, were tested in cyclic voltammetry out of 1000 cycles or more. Two surface preparations, mechanical polishing and an acid passivation treatment, were also used as controls. Surface analysis was primarily by Rutherford backscattering spectrometry. Both the ion-beam mixing and the acid pretreatment increased the lifetimes of films, in comparison with the mechanically polished standards. Reductions in charge injection capability, when they occurred, were attributed to loss of iridium from the films, and there was a close correlation between the charge injection density and the iridium inventory.
Exceeding the solar cell Shockley-Queisser limit via thermal up-conversion of low-energy photons

Abstract Maximum efficiency of ideal single-junction photovoltaic (PV) cells is limited to 33% (for 1 sun illumination) by intrinsic losses such as band edge thermalization, radiative recombination, and inability to absorb below-bandgap photons. This intrinsic thermodynamic limit, named after Shockley and Queisser (S–Q), can be exceeded by utilizing low-energy photons either via their electronic up-conversion or via the thermophotovoltaic (TPV) conversion process. However, electronic up-conversion systems have extremely low efficiencies, and practical temperature considerations limit the operation of TPV converters to the narrow-gap PV cells. Here we develop a conceptual design of a hybrid TPV platform, which exploits thermal up-conversion of low-energy photons and is compatible with conventional silicon PV cells by using spectral and directional selectivity of the up-converter. The hybrid platform offers sunlight-to-electricity conversion efficiency exceeding that imposed by the S–Q limit on the corresponding PV cells across a broad range of bandgap energies, under low optical concentration (1–300 suns), operating temperatures in the range 900–1700 K, and in simple flat panel designs. We demonstrate maximum conversion efficiency of 73% under illumination by non-concentrated sunlight. A detailed analysis of non-ideal hybrid platforms that allows for up to 15% of absorption/re-emission losses yields limiting efficiency value of 45% for Si PV cells.
Thermal effects and mirror surface figure requirements for a diagnostic beamline at the advanced light source

Abstract An imaging beamline based on a Kirkpatrick-Baez mirror configuration has been designed to image the electron beam in the ALS storage ring, to measure its size and shape. The electron beam emittance will be small ( ϵ h = 3.4×10 −9 m rad) and the quality of the image is extremely sensitive to surface figure distortion of the mirrors. Thermal distortions and surface temperatures have been calculated for radiatively cooled mirrors of various materials in a search for a simple design which avoids water cooling. The choice of mirror material and the thermal and mechanical design is discussed.
The SO(32) heterotic string on a K3 surface

Abstract The SO(32) heterotic string on a K3 surface is analyzed in terms of the dual theory of a type II string (or F-theory) on an elliptically fibred Calabi-Yau manifold. The results are in beautiful agreement with earlier work by Witten using very different methods. In particular, we find gauge groups of SO(32) × Sp( k ) appearing at points in the moduli space identified with point-like instantons and see hypermultiplets in the ( 32, 2 k ) representation becoming massless at the same time. We also discuss some aspects of the E 8 × E 8 case.
Bose-Einstein condensate inside a Bragg-reflecting atom cavity

We experimentally realize an atom cavity consisting of a magnetic trap and an optical lattice that extends over the whole trap. When displaced sufficiently from the center of the magnetic trap, dynamics of the atoms are characterized by magnetic confinement on one side of the cavity and Bragg reflection due to the optical lattice on the other side. We demonstrate this atom cavity by recording the momentum-space oscillation of a Bose-Einstein condensate inside the cavity as a function of time. This atom-cavity configuration presents the possibility of realizing a Mach-Zehnder-type atom interferometer.
UPE: Utah prototyping environment for robot manipulators

Developing an environment that enables optimal and flexible design of robot manipulators using reconfigurable links, joints, actuators, and sensors is an essential step for efficient robot design and prototyping. Such an environment should have the right “mix” of software and hardware components for designing the physical parts and the controllers, and for the algorithmic control of the robot modules (kinematics, inverse kinematics, dynamics, trajectory planning, analog control and digital computer control). Specifying object-based communications and catalog mechanisms between the software modules, controllers, physical parts, CAD designs, and actuator and sensor components is a necessary step in the prototyping activities. In this paper, we propose a flexible prototyping environment for robot manipulators with the required subsystems and interfaces between the different components of this environment. This environment provides a close tie between the design parameters of the robot manipulator by the different subsystems involved in the design process. The design and implementation of this environment along with the implementation of some of the subsystems are presented, and some examples that demonstrate the functionality of the environment are discussed. This work was supported in part by DARPA grant N00014-91-J-4123, NSF grant CDA 9024721, and a University of Utah Research Committee grant. All opinions, findings, conclusions or recommendations expressed in this document are those of the author and do not necessarily reflect the views of the sponsoring agencies.
Marine ice-sheet profiles and stability under Coulomb basal conditions

The behavior of marine-terminating ice sheets, such as the West Antarctic ice sheet, is of interest due to the possibility of rapid grounding-line retreat and consequent catastrophic loss of ice. Critical to modeling this behavior is a choice of basal rheology, where the most popular approach is to relate the ice-sheet velocity to a power-law function of basal stress. Recent experiments, however, suggest that near-grounding line tills exhibit Coulomb friction behavior. Here we address how Coulomb conditions modify ice-sheet profiles and stability criteria. The basal rheology necessarily transitions to Coulomb friction near the grounding line, due to low effective stresses, leading to changes in ice-sheet properties within a narrow boundary layer. Ice-sheet profiles ‘taper off’ towards a flatter upper surface, compared with the power-law case, and basal stresses vanish at the grounding line, consistent with observations. In the Coulomb case, the grounding-line ice flux also depends more strongly on flotation ice thickness, which implies that ice sheets are more sensitive to climate perturbations. Furthermore, with Coulomb friction, the ice sheet grounds stably in shallower water than with a power-law rheology. This implies that smaller perturbations are required to push the grounding line into regions of negative bed slope, where it would become unstable. These results have important implications for ice-sheet stability in a warming climate.
An Empirical Examination of Sponsor Influence over the Board of Directors

Investment funds have a unique organization structure in which a fund's board of directors frequently contracts the management of the fund with the fund's sponsor but has a fiduciary duty to act in the interest of the fund's shareholders with regard to decisions such as the shareholder fees charged by the sponsor to manage the fund. For a large sample of closed–end funds, my findings indicate that sponsors exert considerable influence over the board of directors through a variety of mechanisms such as the installation of a sponsor–affiliated board leader, director compensation from service on multiple boards for the sponsor, and control of the director selection process. Furthermore, my examination of closed–end premiums indicates that the market perceives that the absence of sponsor involvement in the director selection process is a credible signal that new directors are not “hand–picked” by the sponsor and that this attribute is positively priced by the market.
Optimization of aircraft engine suspension systems

An interactive computer program has been developed to design aircraft engine mounting systems used for vibration isolation. Mount design is largely driven by two competing criteria. Mounts must be soft enough to provide vibration isolation, yet stiff enough to support the engine without excessive motions. The constrained variable metric optimization technique is used to determine the mount design parameters which minimize the transmitted forces in the mounts, subject to constraints on the maximum allowable deflection of the engine to static forces. The design parameters are the stiffness and orientation of each individual engine mount. The aircraft engine is modeled as a rigid body that is mounted to a rigid base representing the nacelle. An example is used to show that the optimization technique is effective in designing engine mounting system.