cssi/SciSciGPT-SciSciNet huggingface dataset:
Applying an edit distance to the matching of tree ring sequences in dendrochronology

In dendrochronology wood samples are dated according to the tree rings they contain. The dating process consists of comparing the sequence of tree ring widths in the sample to a dated master sequence. Assuming that a tree forms exactly one ring per year a simple sliding algorithm solves this matching task.But sometimes a tree produces no ring or even two rings in a year. If a sample sequence contains this kind of inconsistencies it cannot be dated correctly by the simple sliding algorithm. We therefore introduce a O(α2mn + α4(m + n)) algorithm for dating such a sample sequence against an error-free master sequence, where n and m are the lengths of the sequences. Our algorithm takes into account that the sample might contain up to α missing or double rings and suggests possible positions for these kind of inconsistencies. This is done by employing an edit distance as the distance measure.
SYNTHESIS OF PHENOLIC NATURAL PRODUCTS USING PALLADIUM CATALYZED COUPLING REACTIONS

Derivatives of 2,4-diiodophenol are shown to undergo palladium catalyzed carbonylation and alkyne coupling reactions in excellent to moderate yield and high regioselectivity. The scope of these reactions is explored. Palladium catalyzed reactions are employed as the key steps in the synthesis of three phenolic natural products: Plicatin B, Drupanin and Eutypine.
Do Local Investors Know More? Evidence from Mutual Fund Location and Investments

This study finds that actively managed mutual funds do not display abnormal superior performance in local stocks relative to their own performance in distant stocks. However, the trading behavior of these funds is consistent with a widespread perception that local funds have an informational advantage. This perception is not only held by the local fund managers themselves (who tend to trade more aggressively), but also shared by distant managers (who tend to mimic local managers).
DNA quantification with an electrochemiluminescence microcell

Abstract The detection and quantification of DNA strands using an electrochemiluminescence (ECL) instrument with a microfabricated excitation/detection cell is presented. The microcell is a vertical assembly of silicon and glass substrates, containing thin film Pt electrodes and micromachined fluid channels. A silicon PIN diode photodetector completes the cell assembly. The DNA strands are labeled with an electrochemically exited, luminescing molecule: tris (2,2′ bipyridyl) ruthenium (TBR). The labeled DNA strands are bound to paramagnetic beads with a biotin–streptavidin linkage. The magnetic beads are attracted to the Pt electrode surface with an external magnet, where ECL is excited. With a 1 cm 2 , Pt anode, a detection limit of 40 fmol of DNA is obtained with a silicon PIN diode photodetector operating at room temperature. The overall size of the microcell is only 1.5 cm×2 cm×0.2 cm and supports a sample volume of 150 μl. This is the first demonstration of DNA quantification using an ECL microinstrument.
same-sex weddings, Hindu traditions and modern India

This article examines the phenomenon of same-sex unions, both joint suicides and weddings, mostly among young, low-income, non-English speaking women, that have been reported from many parts of India over the last three decades. Most of the women were Hindus and many of the weddings took place by Hindu rites. None of these women had contact with any LGBT or women's movement or activists before their weddings. Ancient as well as modern texts show that people can and do draw on traditional Hindu ideas about love (as the product of attachments formed in former lives), rebirth (attachments persist from one birth to another) and marriage (which is supposed to outlast one lifetime) to legitimize socially disapproved unions, both cross-sex and same-sex. Right-wing Hindu forces today mistakenly argue that the idea of same-sex love and marriage, and indeed of marriage based on love itself, are Western imports. In fact, same-sex marriages were reported from rural areas and small towns long before the Indian LGBT movement took cognizance of the issue. When families accept them, female couples are generally able to stay together but when families violently oppose them, often with the collusion of local police, couples may be forced to separate or driven to suicide, even though law courts have uniformly upheld the right of consenting adults to live together. Modern Hindu teachers and priests are divided on the question of the validity and desirability of same-sex marriage; a doctrinal debate is now developing.
Zeolite-catalyzed chlorination of toluene by sulfuryl chloride : The effect of zeolite drying

Abstract The initial activity and selectivity of toluene chlorination by sulfuryl chloride was measured using dried and undried samples of four different zeolites: L, X, Y, and ZSM-5. In all cases, removing residual water from the zeolite increases its initial activity. The in-situ removal of water causes a large increase in the para-selectivity of zeolite L, a smaller increase for ZSM-5, and effectively no change for X and Y. The effect of water upon activity and selectivity can be attributed, at least in part, to the formation of aqueous HCl either via hydrolysis of sulfuryl chloride or as a byproduct of the chlorination reaction. Additional experiments show that the amounts of benzyl chloride and poly-chlorinated toluenes are reduced by excluding light and by using dried air to purge the reactor; both procedures reduce the generation of free radicals which otherwise lead to the formation of these byproducts.
Intramolecular Long-Distance Electron Transfer in Organic Molecules

Intramolecular long-distance electron transfer (EI) has been actively studied in recent years in order to test existing theories in a quantitative way and to provide the necessary constants for predicting ET rates from simple structural parameters. Theoretical predictions of an "inverted region," where increasing the driving force of the reaction will decrease its rate, have begun to be experimentally confirmed. A predicted nonlinear dependence of ET rates on the polarity of the solvent has also been confirmed. This work has implications for the design of efficient photochemical charge-separation devices. Other studies have been directed toward determining the distance dependence of ET reactions. Model studies on different series of compounds give similar distance dependences. When different stereochemical structures are compared, it becomes apparent that geometrical factors must be taken into account. Finally, the mechanism of coupling between donor and acceptor in weakly interacting systems has become of major importance. The theoretical and experimental evidence favors a model in which coupling is provided by the interaction with the orbitals of the intervening molecular fragments, although more experimental evidence is needed.
Variation of Néron-Severi ranks of reductions of K3 surfaces

We study the behavior of geometric Picard ranks of K3 surfaces over under reduction modulo primes. We compute these ranks for reductions of smooth quartic surfaces modulo all primes p < 216 in several representative examples and investigate the resulting statistics.
Exploring a contagion model for karst-terrane evolution

Theoretical and geomorphic implications of a contagion model of karst depression and initiation are explored with particular emphasis on (1) identifying parent versus daughter depression subpopulations; (2) analyzing spatial characteristics of each subpopulation; and (3) defining the contagious karst mechanism and how it is transmitted along solution-enlarged joints. The contagious karst mechanism suggests that the presence of one or more parent depressions increases the probability of daughter depressions developing along solution-enlarged joints that radiate outward from beneath parent depressions. In karst terranes where the contagion model applies, there is a well-defined infrastructure with several important elements. Interaction among elements of the infrastructure (hydrologic, structural geologic, and geomorphic) result in clustered depressions. Clusters tend to be randomly distributed and consist typically of a centrally located parent depression surrounded by numerous daughter depressions.
Electrochemical Modeling and Performance of a Lithium- and Manganese-Rich Layered Transition-Metal Oxide Positive Electrode

The impedance of a lithiumand manganese-rich layered transition-metal oxide (LMR-NMC) positive electrode, specifically Li1.2Ni0.15Mn0.55Co0.1O2, is compared to two other transition-metal layered oxide materials, specifically LiNi0.8Co0.15Al0.05O2 (NCA) and Li1.05(Ni1/3Co1/3Mn1/3)0.95O2 (NMC). A more detailed electrochemical impedance spectroscopy (EIS) study is conducted on the LMR-NMC electrode, which includes a range of states-of-charge (SOCs) for both current directions (i.e. charge and discharge) and two relaxation times (i.e. hours and one hundred hours) before the EIS sweep. The LMR-NMC electrode EIS studies are supported by half-cell constant current and galvanostatic intermittent titration technique (GITT) studies. Two types of electrochemical models are utilized to examine the results. The first type is a lithium ion cell electrochemical model for intercalation active material electrodes that includes a complex active material/electrolyte interfacial structure. The other is a lithium ion half-cell electrochemical model that focuses on the unique composite structure of the bulk LMR-NMC materials. © 2015 The Electrochemical Society. [DOI: 10.1149/2.0231504jes] All rights reserved.
Strategy-proof risk sharing

Abstract We consider risk sharing problems with a single good and a finite number of states. Agents have a common prior and their preferences are represented in the expected utility form and are risk averse. We study efficient and individually rational risk sharing rules satisfying strategy-proofness , the requirement that no one can ever benefit by misrepresenting his preference. When aggregate certainty holds, we show that “fixed price selections” from Walrasian correspondence are the only rules satisfying efficiency, individual rationality , and strategy-proofness . However, when aggregate uncertainty holds, we show that there exists no rule satisfying the three requirements. Moreover, in the two agents case, we show that dictatorial rules are the only efficient and strategy-proof rules. Dropping the common prior assumption in the model, we show that this assumption is necessary and sufficient for the existence of rules satisfying the three main requirements in the two agents and aggregate certainty case.
Testing two trade models in Latin American agriculture

Abstract The Heckscher-Ohlin and Markusen models state that countries export the goods intensive in the use of their relatively abundant factor. Latin American agricultural trade is consistent with both models. The paper then shows that Latin American agricultural trade is primarily explained by country differences in relative factor abundance between countries rather than differences in technology. This findings does not reject the Heckscher-Ohlin model but rejects one of Markusen's models.
Recent progress in electron scattering at SLAC

A new experiment on ep elastic scattering at large momentum transfer, Experiment E136, has recently completed data taking. A new measurement of deep inelastic electron scattering from nuclear targets, Experiment E139, has been completed and preliminary results are available. A new program of experiments has begun, called Nuclear Physics at SLAC (NPAS), that will use a new injector on the SLAC linac to provide high intensity beams in the energy range from 0.5 to 6 GeV.
Computing all roots of the likelihood equations of seemingly unrelated regressions

Seemingly unrelated regressions are statistical regression models based on the Gaussian distribution. They are popular in econometrics but also arise in graphical modeling of multivariate dependencies. In maximum likelihood estimation, the parameters of the model are estimated by maximizing the likelihood function, which maps the parameters to the likelihood of observing the given data. By transforming this optimization problem into a polynomial optimization problem, it was recently shown that the likelihood function of a simple bivariate seemingly unrelated regressions model may have several stationary points. Thus local maxima may complicate maximum likelihood estimation. In this paper, we study several more complicated seemingly unrelated regression models, and show how all stationary points of the likelihood function can be computed using algebraic geometry.
Coherence properties near interfaces of random media

The spatial coherence theory of optical fields radiated by statistically homogeneous, infinite, planar sources does not account for detailed surface characteristics. The real scattering media on the other hand have rough interfaces which may affect the field correlation in the neighborhood of the surface. As a result, the statistical characteristics of the interface are expected to also influence the spatial coherence properties of the radiation emitted.
A location management technique to support lifelong numbering in personal communications services

This paper presents a novel location management technique, HOPPER, that is designed to support in a scalable and efficient manner non-geographical (lifelong) personal numbers in Personal Communications Services (PCS). Performance comparisons between our scheme and previous schemes are derived from large scale simulations using a realistic traffic modeling framework for the ten largest cities of the United States. Results show that, in addition to inherently providing nongeographical numbers, the proposed scheme significantly improves lookup performance and requires relatively little database access and network signaling resources.
Observed solar UV irradiance variations of importance to middle atmosphere energetics and photochemistry

Absorption of solar UV irradiance in the spectral interval 120-420 nm is chiefly responsible for radiative heating and photodissociation of important atmospheric constituents (e.g., O2, O3, H2O, NO2, etc.) in the stratosphere, mesosphere, and lower thermosphere. Thus, the absolute value and time perturbations of the UV irradiance could significantly affect the energetics, photochemistry, and subsequent dynamics of these regions. Analysis of preliminary data from the SOLSTICE (UARS) observations for a period of 244 days (3 Oct 1991-2 Jun 1992) is discussed in this paper. The data provide mean daily values of the spectral distribution of the observed irradiances at 1-nm resolution and their solar rotation and semirotation variations. The average amplitudes of the 27-day irradiance oscillations for the 244-day data period were 5.7% at Lyman-alpha (121 nm), 1% at 200 nm, 0.5% at 210 nm, and generally less than 0.2% at wavelengths longer than 280 nm. The average amplitudes of 13.5-day oscillations were, by and large, about half of these values. Solar irradiance variations at 10.7 cm are highly correlated with those at Ly-alpha and other chromospheric emission lines (r = 0.7 to 0.8) and only moderately correlated with irradiances at wavelengths of 180-208 nm (r = 0.5). The correlation decreases as the source region of the irradiance gets closer to the base of the photosphere. At the 2-nm interval 279-281 nm, however, which contains the cores of the Mg II h and k lines, the correlation is again approximately 0.8.
PRIMITIVITY PRESERVING ENDOMORPHISMS OF FREE GROUPS

ABSTRACT An endomorphism of a free group is called primitivity preserving if takes every primitive element to another primitive. In this paper we prove that every primitivity preserving endomorphism of a free group of a finite rank is an automorphism.
Polarization signals of the 21-cm background from the era of reionization

While emission and absorption lines of the 21-cm spin-flip transition of neutral hydrogen are intrinsically unpolarized, a magnetic field creates left- and right-handed polarized components through the Zeeman effect. Here we consider the resulting polarization of the redshifted 21-cm background from the intergalactic medium before reionization. The polarization is most readily detectable in regions with a strong gradient in the mean brightness temperature. In principle, this can open a new window on the evolution of intergalactic magnetic fields. One possible approach is an extended integration of an individual target during this era, such as the Mpc-scale H ii regions inferred to surround quasars at z∼ 6.5. The differential intensity between the two polarization states can be used as a probe of the magnetic field at the edge of the H ii region. We estimate that the Square Kilometer Array (SKA) could (ignoring systematics) detect B∼ 200 (10) μG coherent over several kpc with an observational bandwidth of 100 (2) kHz. Beyond individual sources, the statistical properties of wide-field 21-cm polarization maps, such as the angular power spectrum, can be used to constrain the large-scale magnetic field. In this case, the SKA can detect B∼ 100 μG fields coherent over many Mpc. The magnetic field can be measured in any epoch over which the 21-cm background changes rapidly (e.g. because the ionized fraction or spin temperature change). With either of these methods, a secure detection will require high-precision removal of any polarized foregrounds, which is likely to be a substantial challenge. Our estimates show the level to which the foregrounds must be removed to extract useful cosmological information. Even ignoring foregrounds, the resulting constraints are relatively weak compared to theoretical expectations, but they nevertheless offer a unique direct probe of magnetic fields in the high-redshift universe.
DoublePlay: Parallelizing Sequential Logging and Replay

Deterministic replay systems record and reproduce the execution of a hardware or software system. In contrast to replaying execution on uniprocessors, deterministic replay on multiprocessors is very challenging to implement efficiently because of the need to reproduce the order of or the values read by shared memory operations performed by multiple threads. In this paper, we present DoublePlay, a new way to efficiently guarantee replay on commodity multiprocessors. Our key insight is that one can use the simpler and faster mechanisms of single-processor record and replay, yet still achieve the scalability offered by multiple cores, by using an additional execution to parallelize the record and replay of an application. DoublePlay timeslices multiple threads on a single processor, then runs multiple time intervals (epochs) of the program concurrently on separate processors. This strategy, which we call uniparallelism, makes logging much easier because each epoch runs on a single processor (so threads in an epoch never simultaneously access the same memory) and different epochs operate on different copies of the memory. Thus, rather than logging the order of shared-memory accesses, we need only log the order in which threads in an epoch are timesliced on the processor. DoublePlay runs an additional execution of the program on multiple processors to generate checkpoints so that epochs run in parallel. We evaluate DoublePlay on a variety of client, server, and scientific parallel benchmarks; with spare cores, DoublePlay reduces logging overhead to an average of 15p with two worker threads and 28p with four threads.
Singularly perturbed Markov control problem: limiting average cost

In this paper we consider a singularly perturbed Markov decision process with the limiting average cost criterion. We assume that the underlying process is composed ofn separate irreducible processes, and that the small perturbation is such that it “unites” these processes into a single irreducible process. We formulate the underlying control problem for the singularly perturbed MDP, and call it the “limit Markov control problem” (limit MCP). We prove the validity of the “the limit control principle” which states that an optimal solution to the perturbed MDP can be approximated by an optimal solution of the limit MCP for any sufficiently small perturbation. We also demonstrate that the limit Markov control problem is equivalent to a suitably constructed nonlinear program in the space of long-run state-action frequencies. This approach combines the solutions of the original separated irreducible MDPs with the stationary distribution of a certain “aggregated MDP” and creates a framework for future algorithmic approaches.
Formation of 1-bromocarbonylindazoles via cleavage of 4-bromo ortho-substituted arylsydnones with HBr

Abstract Treatment of 4-bromo-3-arylsydnones containing an ortho -carbonyl substituent ( cf . 1d-j ) with HBr gas leads to the corresponding, novel 1-bromocarbonyl-3-substituted indazoles ( 2d-k ), generally in excellent yield.
On nonstandard Padé approximants suitable for effective properties of two-phase composite materials

This article investigates the existence of the nonstandard Pade approximants introduced by Cherkaev and Zhang [D.-L. Zhang and E. Cherkaev, Reconstruction of spectral function from effective permittivity of a composite material using rational function approximations, J. Comput. Phys. 228 (2009), pp. 5390–5409] for approximating the spectral function of composites from effective properties at different frequencies. The spectral functions contain information on microstructure of composites. Since this reconstruction problem is ill-posed Cherkaev [Inverse homogenization for evaluation of effective properties of a mixture, Inverse Probl. 17 (2001), pp. 1203–1218], the well-performed Pade approach is noteworthy and deserves further investigations. In this article, we validate the assumption that the effective dielectric component of interest of all two-phase composites can be approximated by Pade approximants whose denominator has nonzero power one term. We refer to this as the nonstandard Pade approximant, in...
Predicting the Aoki phase using the chiral lagrangian

Abstract This work is concerned with the phase diagram of Wilson fermions in the mass and coupling constant plane for two-flavor (unquenched) QCD. We show that as the continuum limit is approached, one can study the lattice theory using the continuum chiral Lagrangian, supplemented by additional terms proportional to powers of the lattice spacing. We find two possible phase structures at non-zero lattice spacing: (1) There is an Aoki phase of spontaneously broken flavor and parity, with two massless Goldstone-pions, and a width Δ m 0 ∼ a 3 ; (2) There is no spontaneous symmetry breaking, and all three pions have equal mass of order a . Present numerical simulations suggest that the former option is realized.
A mild C-O bond formation catalyzed by a rhenium-oxo complex.

A mild method for the regioselective synthesis of propargyl ethers by the coupling of propargyl alcohols with a range of other alcohols is described. The method employs an air- and moisture-toleran...
A Comparison of Test Results for Flat-Plate Water-Heating Solar Collectors Using the BSE and ASHRAE Procedures

Five solar collectors were tested according to the BSE and ASHRAE test procedures and the results compared. All five collectors tested were modular, flat-plate, water-heating, and included single- and double-glazed designs with and without selectively coated absorbers. In both procedures, collector efficiency curves are determined. The ASHRAE procedure consists exclusively of outdoor testing whereas the BSE procedure requires a combination of outdoor and indoor testing (no irradiation) to determine the collector’s optical and thermal loss characteristics, respectively. During the indoor testing in this study, the environmental test conditions were controlled and regulated by use of specially built environmental simulators to investigate the effect of wind speed and “sky” temperature on the thermal loss characteristics of the collectors. The simulators provided stable uniform wind speeds in the range of 0 to 7.1 m/s across the collectors and sky temperatures above the collector ranging from ta (ambient-air temperature) to ta - 19 K.
Fast non-iterative single-blur 2-D blind deconvolution of separable and low-rank point-spread functions from finite-support images

The problem of 2-D blind deconvolution is to reconstruct an unknown image from its 2-D convolution with an unknown blur function. Motivated by the superior restoration quality achieved by the recently proposed nullspace-based multichannel image restoration methods, we propose a single-blur restoration approach that avoids the restrictive assumption of multichannel blurring and has the advantage of lower complexity. The assumption made about the image and the blur function is that they both have a finite spatial extent with that of the image being known. Also, the blur is assumed to be either separable or low-rank. If the blur is separable the image can be restored perfectly under noiseless conditions. When the blur is low-rank, favorable results can be achieved if the blur function has large spatial extent relative to the image. This requirement makes the proposed solution suitable for the cases where the degraded images are severely blurred.
Thunder actuator modeling and control with classical and fuzzy control algorithm

Recently the design of curved thunder actuators (deflections from 1 mm - 15 mm) has been a topic of study for many researchers. The work in this study deals with the development of a general technique based on shell theory. The technique can be applied to a broad array of actuators to include: Rainbows, Thunders, C-Blocks and others. The formulation begins with the equations for a general shell theory. Next the equations are reduced to the forms of equations for the particular actuators in a manner that they can be applied to a myriad of curved composite actuators. The technique is then experimentally verified on a Thunder actuator system. Next, the system is controlled using both classical and intelligent control techniques. In addition hardware and circuitry issues are explored.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Insecure Communities: Examining Local Government Participation in U.S. Immigration and Customs Enforcement’s “Secure Communities” Program

In the last several years, suffering global economies, war, ethnic and racial tensions, natural disasters, and other exigencies have led to a steady stream of immigrants to the United States. They seek jobs, refuge, asylum, and better opportunities. In fiscal year 2010, the United States Immigration and Customs Enforcement (ICE) removed a record-setting 392,000 undocumented immigrants, half of which were convicted criminals. Yet a careful look behind this impressive number would undoubtedly reveal families torn apart by the removal of undocumented spouses, parents, siblings, and children convicted only of nonviolent crimes, traffic violations, or other minor infractions. ICE’s own data shows that 79
Approximations for the halstead software science software error rate and project effort estimators

Experimental estimators are presented relating the expected number of software errors (B) in a software development project to* the overal1 reported months of programmer effort for the project (E)* the number of subprograms (n)* the count of thousands of coded source statements (s)These estimators are [EQUATION]These estimators are shown to be consistent with data obtained from, the air force Rome air developement center, the naval research laboratory, and Fujitsu corporation. It is suggested here that more data is needed to refine these estimators further.
Finite element simulations involving simultaneous multiple interface fronts in phase change problems

The present paper describes the simulation of phase change problems involving simultaneous multiple interface fronts employing the finite element method. Much of the past investigations employing finite elements have been restricted to primarily a single phase change situation. The existence of more than one phase, that is, the presence of multiple phase fronts poses certain challenges and further complications. However, the results provide a very interesting thermal behavior for this class of problems. In this paper, attention is focused on fixed grid methods and the trapezoidal family of one-step methods using the enthalpy formulations. Illustrative examples which handle simultaneous multiple fronts in phase change problems are presented.
Signal Progression Impacts on Transit Buses As Travel Time Probes

AbstractWith the deployment Automatic Vehicle Location systems to monitor transit vehicles (and other fleet vehicles), there have been several efforts in recent years that seek to leverage these data to also obtain arterial travel times for the private vehicle population. The fleet vehicle data capture the traffic conditions, but they also capture behavior unique to the fleet, e.g., servicing passengers at a bus stop. There are several strategies used in conventional practice to eliminate the biases that occur in the vicinity of the bus stop. While investigating the benefits of using a perception sensor to identify ambient traffic conditions around the bus and correct for transit operations, the present work revealed that even a perfect correction for local conditions resulted in large deviation between the travel time measured from the bus and the actual travel time experienced by the surrounding private vehicles. This research uncovered a fundamental issue affecting almost all systems that use buses as ...
More facets from fences for linear ordering and acyclic subgraph polytopes

Abstract We present new facets for the linear ordering polytope. These new facets generalize facets induced by subgraphs called fences, introduced by Grotschel (1985) and augmented fences, introduced by McLennan (1990). One novelty of the facets introduced here is that each subgraph induces not one but a family of facets, which are not generally rank inequalities. Indeed, we provide the smallest known example of a facet-representing inequality for the linear ordering polytope that is not a rank inequality. Gilboa (1990) introduced the diagonal inequalities for the linear ordering polytope, and Fishburn (1991) posed the question of identifying precisely which diagonal inequalities represent facets. We completely resolve Fishburn's question. Some of our results can be transported to the acyclic subgraph polytope. These new facets for the acyclic subgraph polytope are the first ones that are not represented by rank inequalities.
Logarithmic convergence of random heuristic search

This paper speaks to the inherent emergent behavior of genetic search. For completeness and generality, a class of stochastic search algorithms, random heuristic search, is reviewed. A general convergence theorem for this class is then proved. Since the simple genetic algorithm (GA) is an instance of random heuristic search, a corollary is a result concerning GAs and time to convergence.
Computation of supersonic flows over three-dimensional configurations

An aerodynamic prediction technique based on the steady form of the full-potential equation has been applied to a variety of three-dimensional supersonic flow problems exhibiting embedded subsonic regions. A conservative switching scheme is employed to transition from the supersonic relaxation algorithm, and vice versa. Numerical solutions are obtained for a number of complex configurations, including advanced tactical fighter, Langley canard-wing fighter configuration, isolated shuttle orbiter, and mated shuttle orbiter configuration with external tank. The computed results are in good agreement with available experimental data.
Have Employment Relationships in the United States Become Less Stable

There has been considerable debate as to whether job stability has declined in the United States. This paper uses data from the Survey of Income and Program Participation (SIPP) to examine the incidence of labor market turnover between 1986 and 1993. Specifically, we calculate one- and two-year separation rates and then analyze turnover by the source of separation. We find that the incidence of job separations did not increase over the period under investigation, but appears to have declined somewhat. When analyzing separations by reason, conditional on separating from an employer, we find little evidence of temporal changes in the composition of turnover that would indicate greater employment instability. Therefore, we do not find conclusive evidence that employment relationships have become more unstable in the recent past.
Social learning and amygdala disruptions in Nf1 mice are rescued by blocking p21-activated kinase

Children with neurofibromatosis type 1 (NF1) are increasingly recognized as having a high prevalence of social difficulties and autism spectrum disorders (ASDs). We demonstrated a selective social learning deficit in mice with deletion of a single Nf1 allele (Nf1(+/-)), along with greater activation of the mitogen-activated protein kinase pathway in neurons from the amygdala and frontal cortex, structures that are relevant to social behaviors. The Nf1(+/-) mice showed aberrant amygdala glutamate and GABA neurotransmission, deficits in long-term potentiation and specific disruptions in the expression of two proteins that are associated with glutamate and GABA neurotransmission: a disintegrin and metalloprotease domain 22 (Adam22) and heat shock protein 70 (Hsp70), respectively. All of these amygdala disruptions were normalized by the additional deletion of the p21 protein-activated kinase (Pak1) gene. We also rescued the social behavior deficits in Nf1(+/-) mice with pharmacological blockade of Pak1 directly in the amygdala. These findings provide insights and therapeutic targets for patients with NF1 and ASDs.
Altering protein specificity: techniques and applications

Protein engineering constitutes a powerful tool for generating novel proteins that serve as catalysts to induce selective chemical and biological transformations that would not otherwise be possible. Protocols that are commonly employed for altering the substrate specificity and selectivity profiles by mutating known enzymes include rational and random methods as well as techniques that entail evolution, selection and screening. Proteins identified by these techniques play important roles in a variety of industrial and medicinal applications and in the study of protein structure-function relationships. Herein we present a critical overview of methods for creating new functional proteins having altered specificity profiles and some practical case studies in which these techniques have been applied to solving problems in synthetic and medicinal chemistry and to elucidating enzyme function and biological pathways.
Tribological Properties of Hard Carbon Films on Zirconia Ceramics

In this study, the authors investigated the tribological properties of hard diamondlike carbon (DLC) films on magnesia-partially stabilized zirconia (MgO-PSZ) substrates over a wide range of bads, speeds, temperatures, and counterface materials. The films were 2 μm thick and produced by ion-beam deposition at room temperature. Tribological tests were conducted on a ball-on-disk machine with MgO-PSZ balls, in open air of 30 to 50% relative humidity under contact loads of 1 to 50 N, at sliding velocities of 0.1 to 6 m/s, and at temperatures of 400°C. Al2O3 and Si3N4 balls were also rubbed against the DLC-coaled MgO-PSZ disks, primarily to assess their friction and wear performance and to compare it with that of MgO-PSZ balls. A series of long-duration lifetime tests was run at speeds of 1, 2, and 6 m/s under a 5 N load to assess the durability of these DLC films. Results showed that the friction coefficients of MgO-PSZ balls sliding against MgO-PSZ disks were 0.5-0.8, and the average specific wear rates of ...
Dynamic threshold body- and gate-coupled SOI ESD protection networks

Abstract Novel silicon-on-insulator (SOI) electrostatic discharge (ESD) protection networks, employing dynamic threshold and body-coupling techniques, have achieved 4 kV HBM ESD robustness levels in preliminary prototype ESD networks. A body- and gate-coupled (B/G-C) SOI dynamic threshold “diode” has been shown to achieve ESD robustness levels of 18.8 V/μm of channel width.
A simple characteristic-free proof of the Brill-Noether theorem

FollowingWelters, we describe howthe use of a different degeneration from that considered by Eisenbud and Harris leads to a simple and characteristic-independent proof of the Brill-Noether theorem using limit linear series. As suggested by the degeneration, we prove an extended version of the theorem allowing for imposed ramification at up to two points.Although experts in the field have long been aware of themain ideas, we address some technical issues which arise in proving the full version of the theorem.
On a theorem of Kac and Gilbert

We prove a general operator theoretic result that asserts that many multiplicity two selfadjoint operators have simple singular spectrum.
Rotor Blade Unsteady Aerodynamic Gust Response to Inlet Guide Vane Wakes

A series of experiments is performed in an extensively instrumented axial flow research compressor to investigate the fundamental flow physics of wake-generated periodic rotor blade row unsteady aerodynamics at realistic values of the reduced freguency. Unique unsteady data are obtained that describe the fundamental unsteady aerodynamic gust interaction phenomena on the first-stage rotor blades of a research axial flow compressor generated by the wakes from the inlet guide vanes. In these experiments, the effects of steady blade aerodynamic loading and the aerodynamic forcing function, including both the transverse and chordwise gust components, and the amplitude of the gusts, are investigated and quantified
Non-equilibrium modifications of the nuclear equation of state

Abstract Non-equilibrium modifications of the nuclear equation of state are assessed in the framework of Extended Irreversible Thermodynamics. The expected size of the non-equilibrium corrections to quantities like the nuclear-matter incompressibility K and the liquid-vapor critical temperature T c are compared to the uncertainties associated at present with the usual equilibrium values. The quantitative estimates are obtained in situations characterized by a stationary planar shear flow of realistic magnitude, or by a stationary temperature gradient.
Loops in combinator-based compilers

In M. Wand (1982, in “Conf. Rec. 9th ACM Sympos. on Principles of Programming Languages,” pp. 234–241, Assoc. Comput. Mach., New York) a paradigm for compilation based on combinators was introduced. A program from a source language is translated (via a semantic definition) to trees of combinators; the tree is simplified (via associative and distributive laws) to a linear, assembly-language-like format; the “compiler writer's virtual machine” operates by simulating a reduction sequence of the simplified tree. The correctness of the transformations follows from general results about the λ-calculus. The code produced by such a generator is always tree-like. In this paper, the method is extended to produce target code with explicit loops. This is done by re-introducing variables into the terms of the target language is a restricted way, along with a structured binding operator. General conditions under which these transformations hold are also considered.
Electrochemical Degradation of Ceramic Electrodes

Calculations of oxygen chemical potentials in the interior of ceramic electrodes with ion blocking interfaces indicate that phase changes and/or decomposition will occur as a result of dc polarization. For electrodes with reversible interfaces, unacceptably thick oxidation layers can form. Results are applied to nonslag and slag-covered MHD electrodes.
Epistemic Conditions for Equilibrium in Beliefs without Independence

Aumann and Brandenburger [Econometrica63(1995), 1161–1180.] provide sufficient conditions on the knowledge of the players in a game for their beliefs to constitute a Nash equilibrium. They assume, among other things, mutual knowledge of rationality. By rationality of a player, it is meant that the action chosen by him maximizes his expected utility, given his beliefs. There is, however, no need to restrict the notion of rationality to expected utility maximization. This paper shows that their result can be generalized to the case where players' preferences over uncertain outcomes belong to a large class of non-expected utility preferences.Journal of Economic LiteratureClassification Numbers: C72, D81.
Total Synthesis of Brevetoxin A: Part 1: First Generation Strategy and Construction of BCD Ring System

Dissection of brevetoxin A at the nine-membered ring site (ring E) formed the basis of the first generation strategy for the total synthesis of this molecule. Unfortuately the planned hydroxy dithioketal cyclization to form the crucial nonacene did not proceed as anticipated and this approach was discontinued.
From caging to grasping

This paper digs into the relationship between cages and grasps of a rigid body. In particular, it considers the use of cages as waypoints to grasp an object. We introduce the concept of pregrasping cages, caging configurations from which an object can be grasped without first breaking the cage. For two-fingered manipulators, all cages are pregrasping cages and, consequently, useful waypoints to grasp an object. A contribution of this paper is to show that the same does not hold for more than two fingers. A second contribution is to show how to overcome that limitation. We explore the natural generalization of the well-understood squeezing/stretching characterization of two-finger cages to arbitrary workspace dimension, arbitrary object shapes without holes, and arbitrary number of point fingers, and exploit it to give sufficient conditions for a cage to be a pregrasping cage. As a product of that generalization, we introduce grasping functions: scalar functions defined on the finger formation that control the process of going from a cage to a grasp. We finish the paper by establishing an analogy between the role of grasping functions in grasping and that of Lyapunov functions in stability theory.
Planetary torques as the viscosity of protoplanetary disks

We revisit the idea that density wave wakes of planets drive accretion in protostellar disks. The effects of many small planets can be represented as a viscosity if the wakes damp locally but the viscosity is proportional to the damping length. Damping occurs mainly because of shocks even for Earth-mass planets. The excitation of the wake follows from standard linear theory including the torque cutoff. We use this as input to an approximate but quantitative nonlinear theory based on Burger's equation for the subsequent propagation and shock. Shock damping is indeed local, but weakly so. If all metals in a minimum-mass solar nebula are invested in planets of a few Earth masses each, dimensionless viscosities (α) of the order of -4 dex to -3 dex result. We compare this with observational constraints. Such small planets would have escaped detection in radial velocity surveys and could be ubiquitous. If so, then the similarity of the observed lifetime of T Tauri disks to the theoretical timescale for assembling a rocky planet may be fate rather than coincidence.
Dephasing of electrons on helium by collisions with gas atoms

The damping of quantum effects in the transport properties of electrons deposited on a surface of liquid helium is studied. It is found that due to vertical motion of the helium vapor atoms, the interference of paths of duration t is damped by a factor $\mathrm{exp}\ensuremath{-}(t/{\ensuremath{\tau}}_{v}{)}^{3}.$ An expression is derived for the weak-localization line shape in the case in which damping occurs by a combination of processes with this type of cubic exponential damping and processes with a simple exponential damping factor.
Endogenous asymmetry in a dynamic procurement auction

We show how to numerically solve for a Markov-perfect equilibrium of a dynamic auction game where a procurer repeatedly purchases construction services from capacity-constrained firms. We find that the procurer is best off scheduling frequent auctions for small project sizes. Otherwise, firm capacity utilization rates become larger and more asymmetric, which softens competition and increases procurement costs. We also find that forward-looking bidding dampens the competition-softening effects of asymmetry: farsighted firms compete more intensely than myopic ones. This can undermine the goal of a bid-preference-style affirmative action program: more farsighted firms respond less to the asymmetry induced via bid preferences.
Multi-leg one-loop gravity amplitudes from gauge theory

Abstract By exploiting relations between gravity and gauge theories, we present two infinite sequences of one-loop n -graviton scattering amplitudes: the ‘maximally helicity-violating’ amplitudes in N = 8 supergravity, and the ‘all-plus’ helicity amplitudes in gravity with any minimally coupled massless matter content. The all-plus amplitudes correspond to self-dual field configurations and vanish in supersymmetric theories. We make use of the tree-level Kawai-Lewellen-Tye (KLT) relations between open and closed string theory amplitudes, which in the low-energy limit imply relations between gravity and gauge theory tree amplitudes. For n ⩽ 6, we determine the all-plus amplitudes explicitly from their unitarity cuts. The KLT relations, applied to the cuts, allow us to extend to gravity a previously found ‘dimension-shifting’ relation between (the cuts of) the all-plus amplitudes in gauge theory and the maximally helicity-violating amplitudes in N = 4 super-Yang-Mills theory. The gravitational version of the relation lets us determine the n ⩽ 6 N = 8 supergravity amplitudes from the all-plus gravity amplitudes. We infer the two series of amplitudes for all n from their soft and collinear properties, which can also be derived from gauge theory using the KLT relations.
Numerical solution of the incompressible boundary-layer equations using the finite element method

A new approach to the solution of the two-dimensional, incompressible, boundary-layer equations based on the Finite Element Method in both directions is investigated. Earlier Finite Element Method treatements of parabolic boundary-layer problems used finite differences in the streamwise direction, thus sacrificing some of the possible advantages of the Finite Element Method. The accuracy and computational efficiency of different interpolation functions for the velocity field are evaluated. A new element especially designed for boundary layer flows is introduced