cssi/SciSciGPT-SciSciNet huggingface dataset:
Cause identification from aviation safety incident reports via weakly supervised semantic lexicon construction

The Aviation Safety Reporting System collects voluntarily submitted reports on aviation safety incidents to facilitate research work aiming to reduce such incidents. To effectively reduce these incidents, it is vital to accurately identify why these incidents occurred. More precisely, given a set of possible causes, or shaping factors, this task of cause identification involves identifying all and only those shaping factors that are responsible for the incidents described in a report. We investigate two approaches to cause identification. Both approaches exploit information provided by a semantic lexicon, which is automatically constructed via Thelen and Riloff's Basilisk framework augmented with our linguistic and algorithmic modifications. The first approach labels a report using a simple heuristic, which looks for the words and phrases acquired during the semantic lexicon learning process in the report. The second approach recasts cause identification as a text classification problem, employing supervised and transductive text classification algorithms to learn models from incident reports labeled with shaping factors and using the models to label unseen reports. Our experiments show that both the heuristic-based approach and the learning-based approach (when given sufficient training data) outperform the baseline system significantly.
Melodrama, reality and crisis: The government–media relationship in Hugo Chávez’s Bolivarian Revolution:

Government–media relationships are both symptomatic and constitutive of a nation. In Venezuela the history of Hugo Chavez’s revolutionary government cannot be written without paying attention to it...
The Nature of Climate and Climatic Variations

The climate system consists of the atmosphere, the oceans, cryosphere (land ice, snow, sea ice), the lithosphere, and the biomass. The behavior of the individual components of the system is governed by processes occurring over a broad range of time and space scales. The components are coupled by physical, biological, and chemical processes, and the coupled system seems capable of undergoing fluctuations on all time scales. In addition to these "internal" climatic processes, external processes (such as variability in the solar irradiance or human activities) must also be considered. Space and time scales of climatic variability are reviewed, with emphasis on the Holocene. Regional patterns of climatic variability may be associated with changes in the amplitude and longitudinal position of the long waves in the westerlies of midlatitudes, and with changes in the intensity and latitude of meridional circulation features such as the Hadley cell. Possible examples of this are mentioned. The variance spectrum of climatic time series is described and certain implications for climate modeling are suggested.
BRST Invariant PV Regularization of SUSY Yang-Mills and SUGRA

Pauli–Villars regularization of Yang–Mills theories and of supergravity theories is outlined, with an emphasis on BRST invariance. Applications to phenomenology and the anomaly structure of supergravity are discussed.
Smoothness, Low Noise and Fast Rates

We establish an excess risk bound of O(HR2n + √HL*Rn) for ERM with an H-smooth loss function and a hypothesis class with Rademacher complexity Rn, where L* is the best risk achievable by the hypothesis class. For typical hypothesis classes where Rn = √R/n, this translates to a learning rate of O(RH/n) in the separable (L* = 0) case and O(RH/n + √L*RH/n) more generally. We also provide similar guarantees for online and stochastic convex optimization of a smooth non-negative objective.
Automatic emittance measurement at the ATF

An automatic emittance measurement system to characterize the transverse emittance of the electron beam produced by the BNL photocathode electron gun is described. The system utilize a VAX workstation and a Spiricon beam analyzer. A operator window (created through the Vista control software package) controls the emittance measurement system and the graphic presentation of the results. Quadrupole variation method is used for the ATF automatic emittance measurement system. A simple emittance formula was derived to study the performance of the quadrupole variation method, and compared with the ATF experimental data is also presented. >
M31* and its circumnuclear environment

We present a multiwavelength investigation of the circumnuclear environment of the Andromeda galaxy (M31), utilizing archival Chandra, FUSE, GALEX, HST and Spitzer data as well as ground-based observations. Based on the Chandra/ACIS data, we tightly constrain the X-ray luminosity of M31 * , the central supermassive black hole (SMBH) of the galaxy, to be L 0.3―7 keV ≤ 1.2 × 10 36 erg s ―1 , approximately one part per 10 10 of the Eddington luminosity. From the diffuse X-ray emission, we characterize the circumnuclear hot gas with a temperature of ∼0.3 keV and a density of ∼0.1 cm ―3 . In the absence of an active SMBH and recent star formation, the most likely heating source for the hot gas is Type Ia supernovae (SNe). The presence of cooler, dusty gas residing in a nuclear spiral has long been known in terms of optical line emission and extinction. We further reveal the infrared emission of the nuclear spiral and evaluate the relative importance of various possible ionizing sources. We show evidence for interaction between the nuclear spiral and the hot gas, probably via thermal evaporation. This mechanism lends natural understandings to (1) the inactivity of M31*, in spite of a probably continuous supply of gas from outer disc regions and (2) the launch of a bulge outflow of hot gas, primarily mass-loaded from the circumnuclear regions. One particular prediction of such a scenario is the presence of gas with intermediate temperatures arising from the conductive interfaces. The FUSE observations do show strong O VIλ1032 and λ1038 absorption lines against the bulge starlight, but the effective column density, No VI ∼ 4 × 10 14 cm ―2 , may be attributed to foreground gas located in the bulge and/or the highly inclined disc of M31, leaving the amount of circumnuclear gas with intermediate temperatures largely uncertain. Our study strongly argues that stellar feedback, particularly in the form of energy release from SNe la, may play an important role in regulating the evolution of SMBHs and the interstellar medium in galactic bulges.
Self-Protection: Antidumping Duties, Collusion and FDI *

It is well established that the threat of antidumping duties can help sustain collusion between a foreign firm and its domestic counterpart. However, when the foreign firm is a multinational, its subsidiary will fight against a new duty, potentially making this threat hollow and collusion less likely. We show that the multinational may therefore choose to submit to a tariff even under collusion since evidence indicates that duties are more difficult to remove than initiate. In this way, it is possible to obtain a greater degree of commitment, although it comes at a cost. Nevertheless, we show that this can be a more profitable strategy than those previously explored. In fact, we find several cases where subsidiaries of multinational firms have indeed filed for protection from their own parents.
WELFARE TO TEMPORARY WORK: IMPLICATIONS FOR LABOR MARKET OUTCOMES

We explore the effects of temporary help employment on welfare recipients' subsequent employment and welfare dynamics. We find that any employment—in temporary help services or other sectors— yields substantial benefits compared to no employment. Although welfare recipients who go to work for temporary help service firms have lower initial wages than those with jobs in other sectors, they experience faster subsequent wage growth. Two years later, they are no less likely to be employed, their wages are close to those of other workers, and they are only slightly more likely to remain on welfare.
Petviashvilli's Method for the Dirichlet Problem

We examine Petviashvilli's method for solving the equation $$ \phi - \Delta \phi = |\phi |^{p-1} \phi $$?-Δ?=|?|p-1? on a bounded domain $$\Omega \subset \mathbb {R}^d$$Ω?Rd with Dirichlet boundary conditions. We prove a local convergence result, using spectral analysis, akin to the result for the problem on $$\mathbb {R}$$R by Pelinovsky and Stepanyants in [16]. We also prove a global convergence result by generating a suite of nonlinear inequalities for the iteration sequence, and we show that the sequence has a natural energy that decreases along the sequence.
A cost‐benefit analysis of R&D tax incentives

. Although technical knowledge generates spillover benefits, production of technical knowledge creates congestion externalities; thus, private R&D investment could be inefficient. A computable general equilibrium model is used to rank tax incentives by their effects on research effort and measure welfare effects. Five results stand out: R&D tax credits produce relatively large increases in research effort and welfare. Lower corporate income tax rates and ITCs for downstream users of high-tech production inputs rank second. Revenue losses from lower personal income tax rates can produce welfare losses. Ironically, ITCs for upstream producers of innovative inputs are ineffective. Incremental R&D credits dominate comprehensive credits. JEL Classification: E62, H21, O38 Une analyse couts avantages des incitations fiscales a investir dans la RD (2) les taux d’imposition plus bas sur les revenus des societes et les credits d’impot pour l’investissement des utilisateurs d’intrants de haute technologie en aval se classent au deuxieme rang; (3) les pertes de revenu attribuables a des taux d’imposition plus bas sur les revenus des personnes peuvent engendrer des pertes de bien-etre; (4) ironiquement, les credits d’impot pour l’investissement des producteurs d’intrants innovateurs en amont sont inefficaces; (5) des credits d’impot additionnels sur la R&D sont preferables a des credits comprehensifs.
Parallel acquisition of PN sequences in DS/SS systems

The authors investigate methods for the parallel acquisition of a PN sequence in a baseband direct sequence spread spectrum system. Four different schemes are considered: the optimal estimation scheme, the maximum-likelihood estimation scheme, a hypothesis-testing scheme that searches over all shifts, and a locally optimum detection scheme. Approximate expressions for the probability of error are derived for the first and last of these schemes and compared with the actual error probabilities obtained via Monte Carlo simulation. Monte Carlo simulation is also used to obtain the error probabilities of the other two schemes and the results for all the schemes are compared. Since the obvious methods of implementing a parallel acquisition scheme require large amounts of hardware or excessive computation, they outline a technique that can be used to reduce the amount of computation. >
Government Debt Issuance in the Euro Area: The Impact of the Financial Crisis

This paper documents and analyzes crisis-related changes in government debt issuance practices in the euro zone countries and Denmark. Using a newly constructed database on primary market debt issuance during 2007–11, we find evidence of a shift away from precrisis standards of best funding practices—competitive auctions of debt instruments with a fixed coupon, long maturity and local currency denomination (DLTF). Exploiting the crosscountry panel data dimension of the data, we conclude that the crisis as such and changes in the macroeconomic environment and investor sentiment can account for a significant proportion of the deviation. The negative effect of the crisis on DLTF debt issuance was especially pronounced in high debt euro area countries, and has forced governments to assume additional risk.
Early warnings of the potential for malaria transmission in rural Africa using the hydrology, entomology and malaria transmission simulator (HYDREMATS)

Background Early warnings of malaria transmission allow health officials to better prepare for future epidemics. Monitoring rainfall is recognized as an important part of malaria early warning systems. The Hydrology, Entomology and Malaria Simulator (HYDREMATS) is a mechanistic model that relates rainfall to malaria transmission, and could be used to provide early warnings of malaria epidemics.
Protecting the computation results of free-roaming agents

When mobile agents do comparison shopping for their owners, they are subject to attacks of malicious hosts executing the agents. We present a family of protocols that protect the computation results established by free-roaming mobile agents. Our protocols enable the owner of the agent to detect upon its return whether a visited host has maliciously altered the state of the agent, thus providing forward integrity and truncation resilience. In an environment without public-key infrastructure, the protocols are based only on a secret hash chain. With a public-key infrastructure, the protocols also guarantee non-repudiability.
Software agents: completing patterns and constructing user interfaces

To support the goal of allowing users to record and retrieve information, this paper describes an interactive note-taking system for pen-based computers with two distinctive features. First, it actively predicts what the user is going to write. Second, it automatically constructs a custom, button-box user interface on request. The system is an example of a learning-apprentice software-agent. A machine learning component characterizes the syntax and semantics of the user's information. A performance system uses this learned information to generate completion strings and construct a user interface.
Monte Carlo study of short-range order and displacement effects in disordered CuAu

Abstract The correlation between local chemical environment and atomic displacements in disordered CuAu alloy has been studied using Monte Carlo simulations based on the effective medium theory of metallic cohesion. These simulations correctly reproduce the chemically specific nearest-neighbour distances in the random alloy across the entire CUxAU1−x concentration range. In the random equiatomic CuAu alloy, the chemically specific pair distances depend strongly on the local atomic environment (i.e. fraction of like/unlike nearest neighbours). In CuAu alloy with short-range order, the relationship between local environment and displacements remains qualitatively similar. However, the increase in short-range order causes the average Cu-Au distance to decrease below the average Cu-Cu distance, as it does in the ordered CuAuI phase. Many of these trends can be understood qualitatively from the different neutral sphere radii and compressibilities of the Cu and Au atoms.
A VERSATILE SYNTHESIS OF FUNCTIONALIZED THIOLS

Abstract The reaction of trimer 6 and an alkyl lithium afforded thilate 7 which reacted with primary halides to produce silyl thioethers in good to excellent yields. The silyl thioethers could be hydrolyzed to the thiols using HF in acetonitrile.
Too far to walk : maternal mortality in context

The Prevention of Maternal Mortality Program is a collaborative effort of Columbia University's Center for Population and Family Health and multidisciplinary teams of researchers from Ghana, Nigeria and Sierra Leone. Program goals include dissemination of information to those concerned with preventing maternal deaths. This review, which presents findings from a broad body of research, is part of that activity. While there are numerous factors that contribute to maternal mortality, we focus on those that affect the interval between the onset of obstetric complication and its outcome. If prompt, adequate treatment is provided, the outcome will usually be satisfactory; therefore, the outcome is most adversely affected by delayed treatment. We examine research on the factors that: (1) delay the decision to seek care; (2) delay arrival at a health facility; and (3) delay the provision of adequate care. The literature clearly indicates that while distance and cost are major obstacles in the decision to seek care, the relationships are not simple. There is evidence that people often consider the quality of care more important than cost. These three factors--distance, cost and quality--alone do not give a full understanding of decision-making process. Their salience as obstacles is ultimately defined by illness-related factors, such as severity. Differential use of health services is also shaped by such variables as gender and socioeconomic status. Patients who make a timely decision to seek care can still experience delay, because the accessibility of health services is an acute problem in the developing world. In rural areas, a woman with an obstetric emergency may find the closest facility equipped only for basic treatments and education, and she may have no way to reach a regional center where resources exist. Finally, arriving at the facility may not lead to the immediate commencement of treatment. Shortages of qualified staff, essential drugs and supplies, coupled with administrative delays and clinical mismanagement, become documentable contributors to maternal deaths. Findings from the literature review are discussed in light of their implications for programs. Options for health programs are offered and examples of efforts to reduce maternal deaths are presented, with an emphasis on strategies to mobilize and adapt existing resources.
Reliability-Based Aircraft Structural Design Pays, Even with Limited Statistical Data

Probabilistic structural design tends to apply higher safety factors to inexpensive or light-weight components, because it is a more efficient way to achieve a desired level of safety. We show that even with limited knowledge about stress probability distributions we can increase the safety of an airplane by following this paradigm. This is accomplished by a small perturbation of the deterministic design that maximizes safety for the same weight. The structural optimization for safety of a representative system composed of a wing, a horizontal tail and a vertical tail is used to demonstrate the paradigm. We find that moving small amount of material from the wing to the tails leads to substantially increased structural safety. Since aircraft companies often apply additional safety factors beyond those mandated by the Federal Aviation Administration (FAA), this opens the door to obtaining probabilistic design that satisfies also the FAA code based rules for deterministic design. We also find that probabilistic design is insensitive to errors committed while assessing the stress probability distribution of the deterministic design, which is the starting point of the probabilistic design. This suggests that using the deterministic design as the basis for the probabilistic design insulates the latter from the extreme sensitivity to statistical data that have been observed in the past. Finally, we find that for independent components subject to the same failure mode, the probabilities of failure at the probabilistic optimum are approximately proportional to the weight. So a component which is ten times lighter than another should be designed to be about 10 times safer.
Collision avoidance analysis for lane changing and merging

One of the riskiest maneuvers that a driver has to perform in a conventional highway system is to merge into the traffic and/or to perform a lane changing maneuver. Lane changing/merging collisions are responsible for one-tenth of all crash-caused traffic delays often resulting in congestion. Traffic delays and congestion, in general, increase travel time and have a negative economic impart. We analyze the kinematics of the vehicles involved in a lane changing/merging maneuver, and study the conditions under which lane changing/merging crashes can be avoided. That is, given a particular lane change/merge scenario, we calculate the minimum longitudinal spacing which the vehicles involved should initially have so that no collision, of any type, takes place during the maneuver. Simulations of a number of examples of lane changing maneuvers are used to demonstrate the results. The results of this paper could be used to assess the safety of lane changing maneuvers and provide warnings or take evasive actions to avoid collision when combined with appropriate hardware on board of vehicles.
Reconstruction of integers from pairwise distances

Given a set of integers, one can easily construct the set of their pairwise distances. We consider the inverse problem: given a set of pairwise distances, find the integer set which realizes the pairwise distance set. This problem arises in a lot of fields in engineering and applied physics, and has confounded researchers for over 60 years. It is one of the few fundamental problems that are neither known to be NP-hard nor solvable by polynomial-time algorithms. Whether unique recovery is possible also remains an open question. In many practical applications where this problem occurs, the integer set is naturally sparse (i.e., the integers are sufficiently spaced), a property which has not been explored. In this work, we exploit the sparse nature of the integer set and develop a polynomial-time algorithm which provably recovers the set of integers (up to linear shift and reversal) from the set of their pairwise distances with arbitrarily high probability if the sparsity is O(n1/2-e). Numerical simulations verify the effectiveness of the proposed algorithm.
An analogue of the baire category theorem

Every definably complete expansion of an ordered field satisfies an analogue of the Baire Category Theorem.
Neutron stars and nuclei in the modified relativistic Hartree approximation

Abstract We have examined the properties of neutron-rich matter and finite nuclei in the modified relativistic Hartree approximation for several values of the renormalization parameter, μ, around the standard choice of μ equal to the nucleon mass M . Observed neutron-star masses do not effectively constrain the value of μ. However, for finite nuclei the value μ / M = 0.79, suggested by nuclear matter data, provides a good account of the bulk properties with a sigma mass of about 600 MeV. This value of μ / M renders the effective three- and four-body scalar self-couplings to be zero at 60% of equilibrium nuclear matter density. We have also found that the matter part of the exchange diagram has little impact on the bulk properties of neutron stars.
Medicinal Chemistry in the Golden Age of Biology: Lessons from Steroid and Peptide Research

Collaboration between biologists and chemists has generated medicines of enormous benefit to society. The dynamics of this synergistic interaction combines two strengths: the rigor of chemistry and the ability of biologists to construct unifying concepts from diverse fields of investigation. The resulting contributions to the practice of medicine have reduced morbidity and mortality while increasing the quality of life. Building on the work of chemists such as Robinson, Prelog, Woodward, and Pauling, medicinal chemists have advanced rational drug discovery, especially of enzyme inhibitors, to a degree unthinkable even twenty years ago. Some of the major contributions of medicinal chemistry to human and animal health stem directly from the creative application of structural and electronic reasoning, from advances in instrumentation, and from spectacular progress in biology. However, medicinal chemists have only begun to scratch the surface of the opportunities made possible by the impact of the “double-helix revolution” of the 1950s.
Estimates of black hole spin properties of 55 sources

Studies of black hole spin and other parameters as a function of redshift provide information about the physical state and merger and accretion histories of the systems. One way that black hole spin may be estimated is through observations of extended radio sources. These sources, powered by outflows from an AGN, allow the beam power and total outflow energy to be studied. In a broad class of models, the beam power of the outflow is related to the spin of the black hole. This relationship is used to estimate black hole spins for 55 radio sources. The samples studied include 7 FR II quasars and 19 FR II radio galaxies with redshifts between 0.056 and 1.79, and 29 radio sources associated with CD galaxies with redshifts between 0.0035 and 0.291. The FR II sources studied have estimated spin values of between about 0.2 and 1; there is a range of values at a given redshift, and the values tend to increase with increasing redshift. Results obtained for FR II quasars are very similar to those obtained for FR II galaxies. A broader range of spin values are obtained for the sample of radio sources associated with CD galaxies studied. The fraction of the spin energy extracted per outflow event is estimated and ranges from about 0.03 to 0.5 for FR II sources and 0.002 to about 1 for radio sources associated with CD galaxies; the data are consistent with this fraction being independent of redshift though the uncertainties are large. The results obtained are consistent with those predicted by numerical simulations that track the merger and accretion history of AGN, supporting the idea that, for AGN with powerful large-scale outflows, beam power is directly related to black hole spin.
AN INVARIANT FOR OPEN VIRTUAL STRINGS

Extended Alexander groups are used to define an invariant for open virtual strings. Examples of non-commuting open strings and a ribbon-concordance obstruction are given. An example is given of a slice open virtual string that is not ribbon. Definitions are extended to open n-strings.
Mariner 10 magnetic field observations of the venus wake

Magnetic field measurements made over a 21-hour interval during the Mariner 10 encounter with Venus were used to study the down-stream region of the solar wind-Venus interaction over a distance of approximately 100 R sub v. For most of the day before closest approach the spacecraft was located in a sheath-like region which was apparently bounded by planetary bow shock on the outer side and either a planetary wake boundary or transient boundary-like feature on the inner side. The spacecraft made multiple encounters with the wake-like boundary during the 21-hour interval with an increasing frequency as it approached the planet. Each pass into the wake boundary from the sheath region was consistently characterized by a slight decrease in magnetic field magnitude, a marked increase in the frequency and amplitude of field fluctuations, and a systematic clockwise rotation of the field direction when viewed from above the plane of the planet orbit.
The use of a Marshallian Macroeconomic Model for policy evaluation : case of South Africa

Using a disaggregated Marshallian macroeconomic model, this paper investigates how the adoption of a set of “free market reforms” may affect the economic growth rate of South Africa. Our findings suggest that the institution of the proposed policy reforms would yield substantial growth in aggregate annual real GDP. The resulting annual GDP growth rate could range from 5.3% to 9.8%, depending on which variant of the reform policies was implemented.
Impact erosion of terrestrial planetary atmospheres

I review current ideas about the nature of the planetesimals - composition, size distribution, and the planetary encounter velocity. Previous papers on accretion and erosion of planetary atmospheres as a result of multiple impacts are reviewed. Finally, the effects of blowing off a substantial fraction of the atmosphere from a terrestrial planet due to a single giant body impact are discussed.
Elimination of harmonics in a multilevel converter using the theory of symmetric polynomials and resultants

A method is presented to compute the switching angles in a multilevel converter so as to produce the required fundamental voltage while at the same time not generate higher order harmonics. Previous work has shown that the transcendental equations characterizing the harmonic content can be converted to polynomial equations which are then solved using the method of resultants from elimination theory. A difficulty with this approach is that when there are several dc sources, the degrees of the polynomials are quite large making the computational burden of their resultant polynomials (as required by elimination theory) quite high. Here, it is shown that the theory of symmetric polynomials can be exploited to reduce the degree of the polynomial equations that must be solved which in turn greatly reduces the computational burden. In contrast to results reported in the literature that use iterative numerical techniques to solve these equations, the approach here produces all possible solutions.
Period variation in BW Vulpeculae redux

Aims. For the past 25 years, BW Vulpeculae has been the topic of period analyses centered on a secular period change with a periodic variation superposed, presumed to be due to light time e ects in a binary system. According to this paradigm, one would expect what seems like a period increase of about 0.5 s during or soon after the year 2001. Methods. I have continued photometric monitoring through the year 2012, adding 35 new timings of maximum and minimum light. Results. This expected change in period did not occur, which rules out that interpretation of the period variation. As of 2012, the observed timings are about two hours early compared to those predicted by the quadratic ephemeris, but are very close to those predicted by the linear ephemeris. Conclusions. In fact, the period has remained constant for the last 32 years, indicating that the previous epochs of constant period are almost certainly the correct interpretation, though the cause of the period changes is still not clear. Continued photometric monitoring of BW Vul leads to the conclusion that the period changes are abrupt, followed by epochs of constant period lasting between 12 and at least 32 years.
Agricultural policy in tropical Africa: is a turnaround possible?

Abstract The food crisis in Africa has entered our living rooms through television and the press. Why is per capita agricultural production lower now than at independence in the early 1960s? This article examines the factors responsible and outlines some solutions. Both external and internal factors have converged to create the crisis — low prices to farmers to placate vocal urban consumers, inefficient, high-cost marketing boards, governments' neglect of agriculture in favor of industry, over-valued exchange rates, lack of foreign exchange and increasing debt burdens. Externally the depressed world market decreased demand for Africa's exports and contributed to the stagnation of the economics. Drought, a population growth rate approaching 3%/year and a shortage of human capital added to the crisis.
Mg11Cu6Al12, A New Link in the Structural Chemistry of MgCu2‐Type Clusters

We report the synthesis and crystal structure of a new phase in the Mg-Cu-Al system: Mg11Cu6Al12. This compound crystallizes in the K17In41 structure type. When written asMg17–xCuxAl12, x = 6, the composition of this phase foretells a connection to Mg17Al12 (α-Mn type). The structures of both can be constructed from 29-atom fragments of the MgCu2 structure type. They differ in the orientations of these fragments: the Mg11Cu6Al12 structure is obtained when half of the MgCu2-type clusters of Mg17Al12 are rotated by 90°. Electronic structure calculations using density functional theory (DFT) and the extended Huckel (eH) method point to driving forces for this structural transformation. Density of states (DOS) curves calculated for Mg11Cu6Al12 in the two structure types indicate that both are stabilized by DOS minima close to the Fermi energy, with the pseudogap being deeper for the observed structure. An eH relative Mulliken population analysis reveals that cluster rotation also changes the electronic character of the outermost sites of the MgCu2-type fragments: six atoms per formula unit go from being ambiguous to anionic, and thus suitable to occupation by relatively electronegative elements. These are the positions occupied by Cu in Mg11Cu6Al12. The creation of these six anionic sites adapted to occupation by Cu provides an impetus for cluster rotation. The removal of ambiguity of the outermost sites of the MgCu2-type fragments creates extended networks of anionic and cationic sites in Mg11Cu6Al12. The cationic sites trace out the clathrate II framework noted by Corbett and co-workers in the K17In41 type, while the anionic sites ensheathe this framework to complete Friauf polyhedra around the framework atoms.
Beam profiling with optical transition radiation

One of the simplest applications of optical transition radiation (OTR) to accelerator beam diagnostics is beam profiling. We compare the limits of resolution of beam profiles made using OTR and profiles made using synchrotron radiation. We will discuss the physical basis for the limiting resolution in each case and show that the case of OTR yields essentially the same result as standard diffraction theory. >
Rank bounds for a hierarchy of Lovász and Schrijver

Lovasz and Schrijver introduced several lift and project methods for 0---1 integer programs, now collectively known as Lovasz---Schrijver (LS) hierarchies. Several lower bounds have since been proven for the rank of various linear programming relaxations in the LS and $$\hbox {LS}_+$$LS+ hierarchies. We investigate rank bounds in the more general $$\hbox {LS}_*$$LS? hierarchy, which allows lifts by any derived inequality as opposed to just $$x\ge 0$$x?0 and $$1-x\ge 0$$1-x?0 in the LS hierarchy. Rank lower bounds for $$\hbox {LS}_*$$LS? were obtained for the symmetric knapsack polytope by Grigoriev et al. We reinitiate further investigation into such general lifts. We prove simple upper bounds on rank which show that under such general lifts one can potentially converge to the integer solution much faster than $$\hbox {LS}_+$$LS+ or Sherali---Adams (SA) hierarchy. This motivates our investigation of rank lower bounds and integrality gaps for $$\hbox {LS}_*$$LS? and the $$\hbox {SA}_*$$SA? hierarchy, the latter is a generalization of the SA hierarchy in the same vein as $$\hbox {LS}_*$$LS?. In particular, we show that the $$\hbox {LS}_*$$LS? rank of $$PHP_n^{n+1}$$PHPnn+1 is $$\sim \log _2n$$~log2n. We also extend the rank lower bounds and integrality gaps for SA hierarchy to the $$\hbox {LS}_*$$LS? and $$\hbox {SA}_*$$SA? hierarchies as long as the maximum number of variables in any constraint of the initial linear program is bounded by a constant.
Assessing the Difference Critique of Deliberation: Gender, Emotion, and the Jury Experience

Despite increasing enthusiasm for political deliberation as a rejuvenating tonic for representative democracy, some theorists question the extent to which deliberative forums adequately incorporate diverse individuals and communication styles. Unfortunately, the theoretical debate between the deliberative theory and the “difference critique” has reached an impasse. To advance this important literature, we derive two formal propositions from each perspective and test these rival claims in the context of the jury system, the most prominent institutionalized deliberative practice in the United States. Surveys of over 3,000 jurors who served in local courthouses indicate that gender and other demographic differences are poor predictors of jurors’ satisfaction with their service experience, including their perceptions of deliberation. The study also shows that emotion—a dimension of deliberative experience presumed to be gendered—is important for both men and women. On balance, the results call into question the power of the difference critique, at least in the context of modern jury deliberation.
TIDAL IMPRINTS OF A DARK SUB-HALO ON THE OUTSKIRTS OF THE MILKY WAY. II. PERTURBER AZIMUTH

We extend our analysis of the observed disturbances on the outskirts of the H I disk of the Milky Way. We employ the additional constraints of the phase of the modes of the observed H I image and asymmetry in the radial velocity to derive the azimuth of the perturber inferred to be responsible for the disturbances in the H I disk. Specifically, we carry out a modal analysis of the phase of the disturbances in the H I image and in high-resolution smoothed particle hydrodynamics (SPH) simulations of a Milky Way like galaxy tidally interacting with dark perturbers, the relative offset of which we utilize to derive the perturber azimuth. Under the assumption that the asymmetry in the radial velocity is due to the perturber, we derive the best fit to the radial velocity at l = 0, 180, and use this constraint to also derive the perturber azimuth. To make a direct connection with observations, we express our results in Sun-centered coordinates, predicting that the perturber responsible for the observed disturbances is between –50 l –10. We explicitly show that the phase of the disturbances in the outskirts of simulated galaxies, our primary metric for the azimuth determination, is relatively insensitive to the equation of state (for the range of gas fractions of local spirals). Our calculations here represent our continuing efforts to develop the "tidal analysis" method of Chakrabarti & Blitz (CB09). CB09 employed SPH simulations to examine tidal interactions between perturbing dark sub-halos and the Milky Way. They found that the amplitudes of the Fourier modes of the observed planar disturbances are best fit by a perturbing dark sub-halo with mass ~one-hundredth that of the Milky Way, and a pericentric approach distance of ~5-10 kpc. The overarching goal of this work is to attempt to outline an alternate procedure to optical studies for characterizing and potentially discovering dwarf galaxies—whereby one can approximately infer the azimuthal location of a perturber, its mass, and pericentric distance (CB09) from analysis of its tidal gravitational imprints on the H I disk of the primary galaxy.
Measuring the financial soundness of U.S. firms, 1926–2012☆

We measure the distribution of firms’ financial soundness over most of the last century for a broad cross section of firms. We highlight three main findings for this key aggregate state variable. First, the three worst recessions between 1926 and 2012 coincided with sharp deteriorations in the financial soundness of all firms, but other recessions did not. Second, fluctuations in total asset volatility, rather than fluctuations in leverage, appear to drive most of the variation in the distribution of firms’ financial soundness. Finally, the distribution of financial soundness for large financial firms 1962–2007 largely resembles that for large nonfinancial firms.
A Heterodinuclear Asymmetric Catalyst for Conjugate Additions of α-Hydroxyketones to β-Substituted Nitroalkenes

The bis-ProPhenol ligand was designed to facilitate formation of hetereodinuclear complexes based upon the large difference in pKa of the one phenolic OH group to the tertiary OH groups. In exploring the first example of hydroxyacetophenones as donors in asymmetric Michael reactions with nitroalkene acceptors, the best stereocontrol was observed with a zinc/magnesium dinuclear complex where enantiomeric excesses ranged up to 92% for the major anti diastereomer.
Linear-to-circular polarization transformation upon optical tunneling through an embedded low-index film

Quarter-wave retardation can be achieved in optical tunneling through a low-index thin film that is surrounded by a medium of higher refractive index, for any index ratio N>2.414, over a range of incidence angles that is determined by N. A novel frustrated-total-internal-reflection circular polarization beam splitter (CPBS) is proposed that uses an adjustable air gap between two Ge prisms. This tunable CPBS operates over a broad (2–12??m) IR spectral range by controlling the air-gap thickness to match one-tenth of the wavelength of light by use of a piezoelectric transducer.
New Hubble Space Telescope Observations of Heavy Elements in Four Metal-Poor Stars

Elements heavier than the iron group are found in nearly all halo stars. A substantial number of these elements, key to understanding neutron-capture nucleosynthesis mechanisms, can only be detected in the near-ultraviolet. We report the results of an observing campaign using the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope to study the detailed heavy-element abundance patterns in four metal-poor stars. We derive abundances or upper limits from 27 absorption lines of 15 elements produced by neutron-capture reactions, including seven elements (germanium, cadmium, tellurium, lutetium, osmium, platinum, and gold) that can only be detected in the near-ultraviolet. We also examine 202 heavy-element absorption lines in ground-based optical spectra obtained with the Magellan Inamori Kyocera Echelle Spectrograph on the Magellan-Clay Telescope at Las Campanas Observatory and the High Resolution Echelle Spectrometer on the Keck I Telescope on Mauna Kea. We have detected up to 34 elements heavier than zinc. The bulk of the heavy elements in these four stars are produced by r-process nucleosynthesis. These observations affirm earlier results suggesting that the tellurium found in metal-poor halo stars with moderate amounts of r-process material scales with the rare earth and third r-process peak elements. Cadmium often follows the abundances of the neighboring elements palladium and silver. We identify several sources of systematic uncertainty that must be considered when comparing these abundances with theoretical predictions. We also present new isotope shift and hyperfine structure component patterns for Lu II and Pb I lines of astrophysical interest.
Incentive Compensation When Executives Can Hedge the Market: Evidence of Relative Performance Evaluation in the Cross Section

Little evidence exists that ¢rms index executive compensation to remove the in£uence of marketwide factors. We argue that executives can, in principle, replicate such indexation in their private portfolios. In support, we ¢nd that market risk has little eiect on the use of stock-based pay for the average executive. But executives’ability to ‘‘undo’’excessive market risk can be hindered by wealth constraints and inalienability of human capital.We replicate the standard result that there is little relative performance evaluation (RPE) for the average executive, but ¢nd strong evidence of RPE for younger executives and executives with less ¢nancial wealth.
Fundamental Structural-Acoustic Idealizations for Structures with Fuzzy Internals

Fundamental issues relative to structural vibration and to scattering of sound from structures with imprecisely known internals are explored, with the master structure taken as a rectangular plate in a rigid baffle, which faces an unbounded fluid medium on the external side. On the internal side is a fuzzy structure, consisting of a random array of point-attached spring-mass systems. The theory predicts that the fuzzy internal structure can be approximated by a statistical average in which the only relevant property is a function m F (Ω) which gives a smoothed-out total mass, per unit plate area, of all those attached oscillators which have their natural frequencies less than a given value Ω. The theory also predicts that the exact value of the damping in the fuzzy structure is of little importance, because the structure, even in the limit of zero damping, actually absorbs energy with an apparent frequency-dependent damping constant proportional to dm F (ω)/dω incorporated into the dynamical description of the master structure. A small finite value of damping within the internals will cause little appreciable change to this limiting value.
A Northern Survey of Gamma-Ray Blazar Candidates

In preparation for the Gamma-Ray Large Area Space Telescope (GLAST), we have compiled a sample of blazar candidates to increase the pool of well-studied active galactic nuclei from which GLAST counterparts will be drawn. Sources were selected with our figure-of-merit (FoM) ranking; thus, they have radio and X-ray properties very similar to the EGRET blazars. Spectroscopic confirmation of these candidates is in progress, and more than 70% of these objects have been identified as flat spectrum radio quasars and BL Lac objects. We present ~250 new optical blazar identifications based on McDonald Observatory spectroscopy, 224 with redshifts. Of these, 167 are in our FoM-selected set. To motivate the γ-ray nature of these objects, we analyzed the current release of the EGRET data for possible point sources at their radio positions. We develop two distinct methods to combine multiple EGRET observations of a sky position into a single detection significance. We report a detection of the signal of the set of blazar candidates in the EGRET data at the >3 σ level by both techniques. We predict that the majority of these blazar candidates will be found by GLAST because of its increased sensitivity, duty cycle, and resolving power.
Statistical re-examination of reported emission lines in the X-ray afterglow of GRB 011211

A 0.2-12 keV spectrum obtained with the XMM-Newton EPIC/pn instrument of GRB 011211, taken in the first 5 ks of a 27-ks observation, was found by Reeves et al. in 2002 to contain emission lines that were interpreted to befrom Mg XI, Si XIV, S XVI, Ar XVIII and Ca XX, at a lower redshift (z o b s = 1.88) than that of the host galaxy (z h o s t = 2.14). We examine the spectrum independently, and find that the claimed lines would not be discovered in a blind search. Specifically, Monte Carlo simulations show that the significance of reported features, individually, is such that they would be observed in 10 per cent of featureless spectra with the same signal-to-noise ratio. Imposing a model in which the two brightest lines would be Si XIV and S XVI Ka emission velocity shifted to between z = 1.88 and 2.40, such features would be found in ∼1.3-1.7 per cent of observed featureless spectra (that is, with 98.3-98.7 per cent confidence). When we account for the number of trials implicit in a search of five energy spectra (as were examined by Reeves et al.), and permit a wider z phase space search (z = 2.14 ′ 1.0), the detection confidence of the two-line complex decreases to 77-82 per cent. We find the detection significance to be insufficient to justify the claim of detection and the model put forth to explain them. Ka line complexes are also found at z = 1.2 and 2.75 of significance equal to or greater than that at z = 1.88. Thus, if one adopts the z = 1.88 complex as significant, one must also adopt the other two complexes to be significant. The interpretation of these data in the context of the model proposed by Reeves et al. is therefore degenerate, and cannot be resolved by these data alone. Our conclusions are in conflict with those of Reeves et al., because our statistical significance accounts for the multiple trials required - but not accounted for by Reeves et al. - in a blind search for emission features across a range of energies. In addition, we describe a practical challenge to the reliability of Monte Carlo ΔΧ 2 tests, as employed by Reeves et al.
Time-domain analysis of EEG during Guilty Knowledge Test: Investigation of epoch extraction criteria

The study of electroencephalography (EEG) for deception detection has long been regarded as an alternative to the standard polygraphy, whose main shortcoming is its unacceptably low level of reliability. Most of the EEG deception research has focused on the amplitude and topography of P300. However, the characteristics of the P300 component are tightly connected to the experimental design and hence counter/measures are easily available for P300-based deception detection. The goal of this study is to evaluate different epoching criteria for the extraction of EEG features that are most suitable for the discrimination between truthful and deceptive responses. In order to reach this aim, a modified version of the Guilty Knowledge Test was used where EEG recordings were obtained from four frontal electrodes and two midline electrodes. In none of the electrodes the P300 component differed between deceptive and truthful responses. Differences have instead been revealed through the extraction of response-locked epochs and analysis of area under the curve.