cssi/SciSciGPT-SciSciNet huggingface dataset:
"The Most Important Thing" Is Value Realization

This article analyzes from a private equity perspective select lessons from Howard Marks’ recently published book, The Most Important Thing (Columbia University Press, 2011). Marks specializes in credit value investments, thus private equity investors may overlook the applicability of his book to their activities.Value realization requires a differentiated approach to strategy, focusing not only on value proposition differentiation—which is the primary focus of the strategy literature—but also on search and capital allocation differentiation and may not necessarily involve the use of “stretch targets,” commonly used today. Irrespective of the management approach, however, the primary activity is to manage the risk of value destruction.
Standing-Wave Suppression for Transcranial Ultrasound by Random Modulation

Low-frequency transcranial ultrasound (?1 MHz) is being investigated for a number of brain therapies, including stroke, tumor ablation, and localized opening of the blood-brain barrier. However, lower frequencies have been associated with the production of undesired standing waves and cavitation in the brain. Presently, we examine an approach to suppress standing waves during continuous-wave (CW) transcranial application. The investigation uses a small randomization in the frequency content of the signal for suppressing standing waves. The approach is studied in an ex-vivo human skull and a plastic-walled chamber, representing idealized conditions. The approach is compared to single-frequency CW operation as well as to a swept-frequency input. Acoustic field scans demonstrate that the swept-frequency method can suppress standing waves in the plastic chamber and skull by 3.4 and 1.6 times, respectively, compared to single-frequency CW excitation. With random modulation, standing waves were reduced by 5.6 and 2 times, respectively, in the plastic chamber and skull. It is expected that the process may play a critical role in providing a safer application of the ultrasound field in the brain and may have application in other areas where standing waves may be created.
Media coverage as a risk factor in suicide

A total of 293 findings from 42 studies on the impact of publicized suicide stories in the media on the incidence of suicide in the real world were analyzed by logistic regression analysis. Studies measuring the effect of either an entertainment or political celebrity suicide story were 14.3 times more likely to find a copycat effect than studies that did not. Studies based on a real as opposed to fictional story were 4.03 times more likely to uncover a copycat effect. Research based on televised stories was 82% less likely to report a copycat effect than research based on newspapers. A review of recent events in Austria and Switzerland indicates that suicide prevention organizations can successfully convince the media to change the frequency and content of their suicide coverage in an effort to reduce copycat effects.
A Spherical Triangle Computer for Marine and Air Navigation

A simple analog computer, which solves the oblique and the right spherical triangle equation, is described based on the law of cosines. With three parameters of the oblique triangle as inputs, the fourth is computed with an accuracy better than ± 10 minutes of arc for most of the practical problems. The computer can be used to solve navigational problems such as the hour angle, course angle and great circle distance. Solutions for the right spherical triangle are obtained when one parameter is set to 90°.
AERODYNAMICS OF TWO SIDE-BY-SIDE PLATES IN HYPERSONIC RAREFIED-GAS FLOWS

Hypersonic rarefied-gas flows near two side-by- side plates have been studied numerically with the direct simulation Monte-Carlo technique under transitional rarefied-gas-flow conditions (Knudsen numbers from 0.024 to 1.8). Strong influences of the geometrical factor (ratio of distance between plates to plate length) and the Knudsen number on the flow structure (the shape of shock waves, the configuration of subsonic flow zones), skin friction, pressure distribution, lift and drag have been found. For small geometrical factors, the repulsive lift force becomes significant with a lift-drag ratio of 1.7 for near- continuum flow, but decreases significantly (0.4) in the near-free-molecular flow. Results show that the lift, drag and lift-drag ratio dependency on the Knudsen number is non-monotonic for various geometrical factors.
A parallel advancing front grid generation scheme

A parallel advancing front scheme has been developed. The domain to be gridded is first subdivided spatially using a relatively coarse octree. Boxes are then identified and gridded in parallel. A scheme that resembles closely the advancing front technique on scalar machines is recovered by only considering the boxes of the active front that generate small elements. The procedure has been implemented on the SGI origin class of machines using the shared memory paradigm. Timings for a variety of cases show speedups similar to those obtained for flow codes. The procedure has been used to generate grids with tens of millions of elements. Copyright © 2001 John Wiley & Sons, Ltd.
The Szemerédi-Trotter theorem in the complex plane

It is shown that n points and e lines in the complex Euclidean plane ?2 determine O(n 2/3 e 2/3 + n + e) point-line incidences. This bound is the best possible, and it generalizes the celebrated theorem by Szemeredi and Trotter about point-line incidences in the real Euclidean plane ?2.
PRESSURE DISTRIBUTION FOR PATCHLIKE CONTACT IN SEALS WITH FRICTIONAL HEATING, THERMAL EXPANSION, AND WEAR.

Sliding contact in seals is known to change at high sliding speed from initially uniform pressure to a deformed state where contact is restricted to small patches of the surface. An earlier analysis of such contact was based upon the assumption of uniform pressure on the small patches. The present study draws upon a thermoelastic influence function to provide simultaneous equations for pressure on subdivisions of the patches. The final result is that at high wear rate (and, consequently, high traversal speed of the patch along the surface of the more conductive body of the contacting pair) the pressure distribution becomes roughly triangular with the maximum pressure toward the leading edge of the patch.
Concerns of Teachers about Implementing Individualized Instruction in the Physical Education Setting

Abstract Teacher concerns about individualized physical education were measured by the Stages of Concern (SoC) questionnaire developed at The University of Texas Research and Development Center. Data were collected immediately before and just following a replicable, seven-week, client-centered, field-based inservice training program involving 15 physical education teachers. A case study approach was used to report group and selected individual concerns profiles. The results of this study indicated that while change is a difficult and time-consuming process, it can be facilitated by trainers focusing on individual teacher's needs and concerns.
Propagation of errors from the sensitivity image in list mode reconstruction

List mode image reconstruction is attracting renewed attention. It eliminates the storage of empty sinogram bins. However, a single back projection of all LORs is still necessary for the pre-calculation of a sensitivity image. Since the detection sensitivity is dependent on the object attenuation and detector efficiency, it must be computed for each study. Exact computation of the sensitivity image can be a daunting task for modern scanners with huge numbers of LORs. Thus, some fast approximate calculation may be desirable. In this paper, we analyze the error propagation from the sensitivity image into the reconstructed image. The theoretical analysis is based on the fixed point condition of the list mode reconstruction. The nonnegativity constraint is modeled using the Kuhn-Tucker condition. With certain assumptions and the first-order Taylor series approximation, we derive a closed form expression for the error in the reconstructed image as a function of the error in the sensitivity image. The result shows that the error response is frequency-dependent and provides a simple expression for determining the required accuracy of the sensitivity image calculation. Computer simulations show that the theoretical results are in good agreement with the measured results.
RLPy: a value-function-based reinforcement learning framework for education and research

RLPy is an object-oriented reinforcement learning software package with a focus on value-function-based methods using linear function approximation and discrete actions. The framework was designed for both educational and research purposes. It provides a rich library of fine-grained, easily exchangeable components for learning agents (e.g., policies or representations of value functions), facilitating recently increased specialization in reinforcement learning. RLPy is written in Python to allow fast prototyping, but is also suitable for large-scale experiments through its built-in support for optimized numerical libraries and parallelization. Code profiling, domain visualizations, and data analysis are integrated in a self-contained package available under the Modified BSD License at http://github.com/rlpy/rlpy. All of these properties allow users to compare various reinforcement learning algorithms with little effort.
Synthesis and Application of Chiral Cyclopropane-Based Ligands in Palladium-Catalyzed Allylic Alkylation

A series of chiral, cyclopropane-based phosphorus/sulfur ligands have been synthesized and evaluated in the palladium-catalyzed allylic alkylation of 1,3-diphenylpropenyl acetate with dimethyl malonate. Variation of the ligand substituents at phosphorus, sulfur, and the carbon backbone revealed 24d to have the optimal configuration for this reaction, giving the product in high yield and with good enantioselectivity (93%). A model for the observed enantioselectivity is discussed within the context of existing models, using X-ray crystallographic data, solution-phase NMR studies, and the absolute stereochemistry of the products. Selected ligands were also evaluated in the palladium-catalyzed intermolecular Heck reaction and the rhodium-catalyzed hydrogenation of a dehydroamino acid.
Star clusters in the interacting galaxy system Arp 284

We present results from a study of protoglobular cluster candidates in the interacting galaxy system Arp 284 (NGC 7714/5) using data from the Hubble Space Telescope (HST). Previous studies of the Antennae and M51 have suggested that the majority of young massive star clusters dissolve within 20 Myr due to mass loss. We use the evolutionary synthesis code starburst99 to estimate ages and extinctions for approximately 175 clusters visible with HST. We also use lower resolution Galaxy Evolution Explorer and ground-based Hα data to estimate the ages of the giant H ii regions in which these clusters are found, and compare the Spitzer colours of these H ii regions to those of star-forming regions in other interacting systems. The ages are also used to aid in the interpretation of Chandra X-ray data. Clusters in the tidal tails of NGC 7714 are generally found to have ages less than 20 Myr, though observational limits make the significance of this result uncertain. Older clusters, though not numerous, have nearly the same spatial distribution within the imaged portion of NGC 7714 as young clusters. The cluster population in the bridge connecting the two galaxies appears to be older, but the data in this part of the system are too limited to draw firm conclusions. The ages of the giant H ii regions in NGC 7714 are generally older than those of their constituent clusters, possibly indicating that the young clusters we detect are surrounded by their dispersed predecessors.
Instabilities of a gyroscope produced by rapidly rotating, highly viscous liquids

Abstract : A series of experiments were conducted to determine the yaw behavior of a gyroscope that contained a liquid-filled rotor. Spin rates, liquid viscosities, and cylinder geometries were selected to produce a wide range of Reynolds numbers (5 1,000, the motion of the gyroscope was reasonably well predicted by classical liquid-filled shell theories that postulate a resonance between a natural frequency of the spinning liquid and the yaw frequency of the gyroscope. For these conditions the maximum yaw growth rate will occur when an eigenfrequency of the liquid is approximately equal to the gyroscope yaw frequency. For cases where RE< 1,000, the behavior of the gyroscope was not characterized by a resonant mechanism. Instead, the liquid- induced yaw moments and yaw growth rates grew monotonically with increasing yaw frequencies.
A second-generation synthesis of scalemic 3,5,5-trisubstituted pyrrolin-4-ones: Incorporation of functionalized amino acid side-chains

Abstract To access mimics of peptidal β-strands ( 1 ), scalemic 3,5,5-trisubstituted pyrrolin-4-ones bearing the tyrosine, serine, and lysine side-chains have been generated via cyclization of metalated imino esters and deprotection. The functionalized imino esters were prepared by asymmetric alkylation of a common oxazolidinone precursor ( 2 ) derived from L-prenylglycine.
The Complementary Roles of Mitigation and Insurance in Managing Catastrophic Risks

This paper examines the impact that insurance coupled with specific risk mitigation measures (RMMs) could have on reducing losses from hurricanes and earthquakes as well as improving the solvency position of insurers who provide coverage against these hazards. We first explore why relatively few individuals adopt cost-effective RMMs by reporting on the results of empirical studies and controlled laboratory studies. We then investigate the impact that an RMM has on both the expected losses and those from a worst case scenario in two model cities—Oakland (an earthquake-prone area) and Miami/Dade County (a hurricane-prone area) which were constructed respectively with the assistance of two modeling firms. The paper then explores three programs for forging a meaningful public-private sector partnership: well-enforced building codes, insurance premium reductions linked with long-term loans, and lower deductibles on insurance policies tied to mitigation. We conclude by briefly examining four issues for future research on linking mitigation with insurance.
Behavior of the Heisenberg ferromagnet for temperatures near and above the transition point

Abstract The Heisenberg model of magnetism is examined near and above its transition point by two self-consistent field approximations. The first approximation is the random phase approximation (RPA) which contains no critical fluctuations in the ferromagnetic state. The second approximation (a modified RPA treatment) contains the critical fluctuations for both phases, gives a necessary but not sufficient condition on the region of validity for the RPA, and shows that the critical fluctuations lead to an infinite specific heat capacity. Discrete and continuum treatments of the lattice are also presented. It is found that the paramagnetic state is much more sensitive to the details of the exchange interaction than the ferromagnetic state.
An Empirical Evaluation of Automated Theorem Provers in Software Certification

We describe a system for the automated certification of safety properties of NASA software. The system uses Hoare-style program verification technology to generate proof obligations which are then processed by an automated first-order theorem prover (ATP). We discuss the unique requirements this application places on the ATPs, focusing on automation, proof checking, traceability, and usability, and describe the resulting system architecture, including a certification browser that maintains and displays links between obligations and source code locations. For full automation, the obligations must be aggressively preprocessed and simplified, and we demonstrate how the individual simplification stages, which are implemented by rewriting, influence the ability of the ATPs to solve the proof tasks. Our results are based on 13 comprehensive certification experiments that lead to 366 top-level safety obligations and ultimately to more than 25,000 proof tasks which have been used to determine the suitability of the high-performance provers DCTP, E-Setheo, E, Gandalf, Otter, Setheo, Spass, and Vampire, and our associated infrastructure. The proofs found by Otter have been checked by Ivy.
Modular Strategy for the Synthesis of Functionalized Aryl-Fused Azabicyclo[2.2.2]octanes via Sequential Cu/Pd/Ru Catalysis

Aryl-fused 2-azabicyclo[2.2.2]octanes were prepared by a novel sequence of Cu-catalyzed three-component coupling of diversely substituted N-benzyl o-bromoaryl imines with methacryloyl chloride and vinyltributyl stannane followed by Pd-catalyzed Heck annulation. Subsequent diversification of the aryl-fused 2-azabicyclo[2.2.2]octane core was achieved by attaching a flexible linker and a potential second pharmacophore via Ru-catalyzed cross-metathesis and a nucleophilic substitution.
Active optical antenna

We have modeled and implemented optical antennas on the facet of a commercial near-infrared diode laser, and have directly observed the highly localized enhancement of the laser field using an apertureless NSOM.
Cumulative Effects on Weight Due to an Initial Occupational Choice as a Blue Collar Worker

The objective is to estimate the effect on one’s weight decades later of choosing a blue-collar job as his/her initial job. Various two stage models treat occupational choice to be endogenous. Using strong instrumental variables to identify occupational choice yields statistically significant results indicating that the initial choice of a blue-collar job is associated with an increase of 6.6 percent (4.8 percent) in the probability of being overweight (obese). We also find that an additional year of blue-collar work is associated with an increase of 1.1 percent and 1.4 percent in the probability of being overweight and obese, respectively.
Exploiting Behavioral Hierarchy for Efficient Model Checking

Inspired by the success of model checking in hardware and protocol verification, model checking techniques for software have been the focus of a lot of research in the last few years [5,3,2,6]. Model checking can be applied only to relatively small models due to its inherently high computational requirements, and there are two complementary trends to address scalability. The model extraction approach, exemplified by projects such as Bandera [6] and SLAM [3], involves constructing inputs to model checkers by abstracting programs written in languages such as C and Java. The model-based design approach, exemplified by modeling notations such as Statecharts [7], promotes design using high-level models that are compiled into code. Our research agenda is to develop model checking techniques for model-based design of software.
Circulating natriuretic peptide concentrations reflect changes in insulin sensitivity over time in the Diabetes Prevention Program

Aims/hypothesis We aimed to study the relationship between measures of adiposity, insulin sensitivity and N-terminal pro-B-type natriuretic peptide (NT-proBNP) in the Diabetes Prevention Program (DPP).
The Clarkson–Shor Technique Revisited and Extended

We provide an alternative, simpler and more general derivation of the Clarkson–Shor probabilistic technique [7] and use it to obtain several extensions and new combinatorial bounds.
Natural variation in preparation for nutrient depletion reveals a cost-benefit tradeoff.

Maximizing growth and survival in the face of a complex, time-varying environment is a common problem for single-celled organisms in the wild. When offered two different sugars as carbon sources, microorganisms first consume the preferred sugar, then undergo a transient growth delay, the “diauxic lag,” while inducing genes to metabolize the less preferred sugar. This delay is commonly assumed to be an inevitable consequence of selection to maximize use of the preferred sugar. Contrary to this view, we found that many natural isolates of Saccharomyces cerevisiae display short or nonexistent diauxic lags when grown in mixtures of glucose (preferred) and galactose. These strains induce galactose utilization (GAL) genes hours before glucose exhaustion, thereby “preparing” for the transition from glucose to galactose metabolism. The extent of preparation varies across strains, and seems to be determined by the steady-state response of GAL genes to mixtures of glucose and galactose rather than by induction kinetics. Although early GAL gene induction gives strains a competitive advantage once glucose runs out, it comes at a cost while glucose is still present. Costs and benefits correlate with the degree of preparation: strains with higher expression of GAL genes prior to glucose exhaustion experience a larger upfront growth cost but also a shorter diauxic lag. Our results show that classical diauxic growth is only one extreme on a continuum of growth strategies constrained by a cost–benefit tradeoff. This type of continuum is likely to be common in nature, as similar tradeoffs can arise whenever cells evolve to use mixtures of nutrients.
Enticing for me but unfair to her: Can targeted pricing evoke socially conscious behavior? ☆

Prior research shows that consumers stop purchasing from firms that treat them badly. In this research we show that consumers also resist firms that treat other consumers badly while favoring them. In three experiments, we demonstrate such social consciousness in the context of targeted pricing, where firms offer lower prices to new (versus old) customers. A significant proportion of consumers in our experiments give up money to resist the price-discriminating firm, especially when the discrimination is more salient or is not justified. Further, perceived unfairness mediates the relationship between the salience and justification of the pricing practice and consumer resistance.
Social Institutions and Work Centrality: Explorations Beyond National Culture

In spite of the popularity of institutional explanations of organizational form, most international management research uses dimensions of national culture to explain cross-national differences in individual work centrality. In this study, we show that social institutions explain variance in work centrality in addition to Hofstede's (2001) dimensions of national culture. Using individual-level data from 30,270 interview respondents from the World Value Survey and institutional data for their 26 countries, we developed hypotheses to investigate whether selected social institutions (i.e., socialism, union strength, educational accessibility, social inequality, and industrialization) affect individual work centrality. We tested our cross-level hypotheses using Hierarchical Linear Modeling. Findings showed that all of the social institutional variables studied predicted lower work centrality.
Automatic discovery of cell types and microcircuitry from neural connectomics

Neural connectomics has begun producing massive amounts of data, necessitating new analysis methods to discover the biological and computational structure. It has long been assumed that discovering neuron types and their relation to microcircuitry is crucial to understanding neural function. Here we developed a non-parametric Bayesian technique that identifies neuron types and microcircuitry patterns in connectomics data. It combines the information traditionally used by biologists in a principled and probabilistically coherent manner, including connectivity, cell body location, and the spatial distribution of synapses. We show that the approach recovers known neuron types in the retina and enables predictions of connectivity, better than simpler algorithms. It also can reveal interesting structure in the nervous system of Caenorhabditis elegans and an old man-made microprocessor. Our approach extracts structural meaning from connectomics, enabling new approaches of automatically deriving anatomical insights from these emerging datasets. DOI: http://dx.doi.org/10.7554/eLife.04250.001
Distinct Patterns of Expression and Evolution of Intronless and Intron-Containing Mammalian Genes

Comparison of expression levels and breadth and evolutionary rates of intronless and intron-containing mammalian genes shows that intronless genes are expressed at lower levels, tend to be tissue specific, and evolve significantly faster than spliced genes. By contrast, monomorphic spliced genes that are not subject to detectable alternative splicing and polymorphic alternatively spliced genes show similar statistically indistinguishable patterns of expression and evolution. Alternative splicing is most common in ancient genes, whereas intronless genes appear to have relatively recent origins. These results imply tight coupling between different stages of gene expression, in particular, transcription, splicing, and nucleocytosolic transport of transcripts, and suggest that formation of intronless genes is an important route of evolution of novel tissue-specific functions in animals.
Labyrinthine Instability in Dielectric Fluids

The dual to recent work of the labyrinthine instability in magnetic fluids is demonstrated with analysis and measurements using dielectric fluids. Here polarizable fluid layers are placed within an initially uniform electric field tangential to the fluid interface separating two dielectric fluid layers. To eliminate electric space charge effects, alternating electric fields must be applied at a frequency much greater than the larger reciprocal dielectric relaxation time of the fluids. Past theory and measurements have shown that a flat interface in a uniform tangential field is stable if the interface is of infinite extent. If the fluid interface has a finite thickness in the direction of the applied field, reaction fields cause nonuniform field components tangential to the fluid interface. Above a critical magnitude the resultant field destabilizes the fluid interface forming labyrinthine patterns. An interfacial stability analysis and an energy minimization method are compared to measurements.
Model-Reference Longitudinal Control for Automated Vehicle Systems

The problem of designing longitudinal control systems which provide acceleration and jerk limited response for automated vehicle systems is examined. Non-dimensional models of vehicles propelled by d-c traction motors are used to evaluate the feasibility of the model-reference control concept. Analytical and computer simulation techniques are used to evaluate performance and assure critical string behavioral characteristics - asymptotic string stability and fixed end-point speed transition region (proper curve negotiation).
Optimal Dynamic Nonlinear Income Taxes with No Commitment

We wish to study optimal dynamic nonlinear income taxes. Do real-world taxes share some of their features? What policy prescriptions can be made? We study a two-period model, where the consumers and government each have separate budget constraints in the two periods, so income cannot be transferred between periods. Labor supply in both periods is chosen by consumers. The government has memory, so taxes in the first period are a function of first-period labor income, whereas taxes in the second period are a function of both first- and second-period labor incomes. The government cannot commit to future taxes. Time consistency is thus imposed as a requirement. The main results of the paper show that time-consistent incentive-compatible two-period taxes involve separation of types in the first period and a differentiated lump-sum tax in the second period, provided that the discount rate is high or utility is separable between labor and consumption. In the natural extension of the Diamond () model with quasi-linear utility functions to two periods, an equivalence of dynamic and static optimal taxes is demonstrated, and a necessary condition for the top marginal tax rate on first-period income is found.
Palladium‐Catalyzed Synthesis of (Hetero)Aryl Alkyl Sulfones from (Hetero)Aryl Boronic Acids, Unactivated Alkyl Halides, and Potassium Metabisulfite

A palladium-catalyzed one-step synthesis of (hetero)aryl alkyl sulfones from (hetero)arylboronic acids, potassium metabisulfite, and unactivated or activated alkylhalides is described. This transformation is of broad scope, occurs under mild conditions, and employs readily available reactants. A stoichiometric experiment has led to the isolation of a catalytically active dimeric palladium sulfinate complex, which was characterized by X-ray diffraction analysis.
Bistatic Radar Cross Sections of Chaff

Bistatic cross sections applicable to scattering from a cloud of randomly positioned and randomly oriented resonant dipoles, or chaff, are found. The chaff cloud can have an arbitrary location relative to an illuminating radar and the radar antenna can have an arbitrarily specified polarization. The receiver can be located arbitrarily in relation to the radar and chaff cloud and can also have arbitrary polarization (different from the transmitter antenna). Average cross sections are found for a preferred receiver polarization and the corresponding orthogonal polarization. Results are reduced to simple, easily applied expressions, and several examples are developed to illustrate the ease with which the general results can be applied in practice.
Thermal Cycle Reliability and Failure Mechanisms of CCGA and PBGA Assemblies With and Without Corner Staking

Area array packages (AAPs) with 1.27 mm pitch have been the packages of choice for commercial applications; they are now starting to be implemented for use in military and aerospace applications. Thermal cycling characteristics of plastic ball grid array (PBGA) and chip scale package assemblies, because of their wide usage for commercial applications, have been extensively reported on in literature. Thermal cycling represents the on-off environmental condition for most electronic products and therefore is a key factor that defines reliability. However, very limited data is available for thermal cycling behavior of ceramic packages commonly used for the aerospace applications. For high reliability applications, numerous AAPs are available with an identical design pattern both in ceramic and plastic packages. This paper compares assembly reliability of ceramic and plastic packages with the identical inputs/outputs (I/Os) and pattern. The ceramic package was in the form of ceramic column grid array (CCGA) with 560 I/Os peripheral array with the identical pad design as its plastic counterpart. The effects of the following key parameters on reliability of both CCGA and PBGA assemblies were investigated:(1) thermal cycle ranges, -50degC/75degC, -55degC/100degC, and -55degC/125degC; (2) corner staking on failure mechanisms for two thermal cycle profiles, -55degC/125degC and -50degC/75degC; (3) package interchangeability, i.e., using PBGA package on CCGA pad design with a larger pad. Packages were assembled on polyimide boards and their daisy chains were continuously monitored. Optical photomicrographs were taken at various thermal cycle intervals to document damage progress and behavior. Representative samples along with their cross-sectional photomicrographs at higher magnification, taken by scanning electron microscopy and analyzed by energy dispersive X-ray, are also presented. The inspection documents were used to determine crack propagation and failure analyses for packages with and without corner staking. In assemblies with corner staking adhesive, a transition in failure from corner columns to center columns was observed when maximum temperature in thermal cycling profiles changed. This is a new failure mechanism not reported on in literature. Finite element analysis (FEA) was used to predict such global failure mode changes. FEA findings are also presented.
Synthesis of isocoumarins and α-pyrones via iodocyclization

Abstract A variety of 3-substituted 4-iodoisocoumarins and 6-substituted 5-iodo-2(2H)-pyranones are readily prepared in excellent yields under mild reaction conditions by the reaction of o-(1-alkynyl)benzoates and (Z)-2-alken-4-ynoates with ICl.
Geometric study of Lagrangian and Eulerian structures in turbulent channel flow

We report the detailed multi-scale and multi-directional geometric study of both evolving Lagrangian and instantaneous Eulerian structures in turbulent channel flow at low and moderate Reynolds numbers. The Lagrangian structures (material surfaces) are obtained by tracking the Lagrangian scalar field, and Eulerian structures are extracted from the swirling strength field at a time instant. The multi-scale and multi-directional geometric analysis, based on the mirror-extended curvelet transform, is developed to quantify the geometry, including the averaged inclination and sweep angles, of both structures at up to eight scales ranging from the half-height δ of the channel to several viscous length scales δν. Here, the inclination angle is on the plane of the streamwise and wall-normal directions, and the sweep angle is on the plane of streamwise and spanwise directions. The results show that coherent quasi-streamwise structures in the near-wall region are composed of inclined objects with averaged inclination angle 35°–45°, averaged sweep angle 30°–40° and characteristic scale 20δν, and ‘curved legs’ with averaged inclination angle 20°–30°, averaged sweep angle 15°–30° and length scale 5δν–10δν. The temporal evolution of Lagrangian structures shows increasing inclination and sweep angles with time, which may correspond to the lifting process of near-wall quasi-streamwise vortices. The large-scale structures that appear to be composed of a number of individual small-scale objects are detected using cross-correlations between Eulerian structures with large and small scales. These packets are located at the near-wall region with the typical height 0.25δ and may extend over 10δ in the streamwise direction in moderate-Reynolds-number, long channel flows. In addition, the effects of the Reynolds number and comparisons between Lagrangian and Eulerian structures are discussed.
Platinum(II)-catalyzed intermolecular hydroarylation of unactivated alkenes with indoles.

Ethylene, α-olefins, and vinyl arenes undergo platinum-catalyzed hydroarylation with substituted indoles in moderate to good yield.
The Price-Marginal Cost Markup and its Determinants in U.S. Manufacturing

This paper estimates the price-marginal cost markup for US manufacturing using a new methodology. Most existing techniques of estimating the markup are a variant on Hall's (1988) framework involving the manipulation of the Solow Residual. However this paper argues that this notion is based on the unreasonable assumption that labor can be costlessly adjusted at a fixed wage rate. By relaxing this assumption, we are able to derive a generalized markup index, which when estimated using manufacturing data is highly countercyclical and decreasing in trend since the 1960s. When we then seek to explain what causes the manufacturing markup to behave in this way, the most important determinant is the share of imported goods in the industry. Thus, increasing foreign competition in manufacturing has led to a decline in the industry's markup over time.
Numerical Simulation Simplifications for Coupled Natural Convection and Radiation in Small Enclosures with a Cylindrical Obstruction

A finite control volume numerical model was used to estimate the relative magnitude of natural convection and radiation in small enclosures with a cylindrical obstruction. The enclosure had a height of 2.54 cm, widths between 5.08 cm and 10.16 cm, depth of 5.08 cm, and obstruction diameters between 0.51 cm and 1.52 cm. Temperatures ranging from 310 K to 1275 K were placed on the right boundary. These temperatures represented heating from a pool fuel fire. Simulations were run for an hour to determine the temperature response inside the enclosure and obstruction. Another simulation was run where the right boundary temperature was stepped by 40 K/min to represent a transient temperature ramp up from a fire. When two conditions are met, natural convection can be ignored, and only enclosure radiation is necessary for reaching a solution within 10% of results when all heat transfer modes are included. These conditions are when the right boundary temperatures are continuously above 800 K or when the temperature...
Multiple attenuation in the image space

Multiples can be suppressed in the angle-domain image space after migration. For a given velocity model, primaries and multiples have different angle-domain moveout and, therefore, can be separated using techniques similar to the ones employed in the data space prior to migration. We use Radon transforms in the image space to discriminate between primaries and multiples and employ accurate functions describing angledomain moveouts. Since every individual angle-domain common-image gather incorporates complex 3D propagation effects, our method has the advantage of working with 3D data and complicated geology. Therefore, our method offers an alternative to the more expensive surface-related multiple-elimination (SRME) approach operating in the data space. Radon transforms are cheap but not necessarily ideal for separating primaries and multiples, particularly at small angles where the moveout discrepancy between the two kinds of events are not large. Better techniques involving signal/noise separation using prediction-error filters can be employed as well, although such approaches fall outside the scope of this paper. We demonstrate, using synthetic and real data examples, the power of our method in discriminating between primaries and multiples after migration by wavefield extrapolation, followed by transformation to the angle domain.
Cooperative transmission for random access wireless networks

We propose a novel high-throughput medium access scheme for wireless networks that is suitable for bursty sources. We view the wireless network as a spatially distributed antenna, with antenna elements linked via the wireless channel. When there is a collision, the packets involved in the collision are saved in a buffer. In the slots following the collision, a set of nodes, designated as relays, form an alliance and bounce off the signal that they received during the collision slot. By processing the originally collided packets and the signals forwarded by the relays, the destination node can formulate and solve a multiple-input multiple-output problem, the inputs of which are the original packets. The spatial diversity introduced via the cooperative relaying enables us to deal with the wireless channel effectively without any bandwidth expansion nor additional antenna hardware. The proposed scheme maintains the benefits of ALOHA systems in the sense that all nodes share access to media resources efficiently and without extra scheduling overhead, and enables efficient use of network power.
Avalanche crown‐depth distributions

[1] The literature disagrees about the statistical distribution of snow avalanche crown depths. Large datasets from Mammoth Mountain, California and the Westwide Avalanche Network show that the three-parameter generalized extreme value distribution provides the most robust fit, followed by a two-parameter variation, the Frechet distribution. The most parsimonious explanation is neither self-organized criticality nor other complex cascades, but the maximum domain of attraction, implying that distributions of individual avalanche crown depths are scaling. We also show that crown depths do not have a universal tail index. Rather, they range from 2.8 to 4.6 over different avalanche paths, consistent with other geophysical phenomena such as wildfires, which show similar variability.
Maximal Thurston-Bennequin Number of Two-Bridge Links

We compute the maximal Thurston-Bennequin number for a Legendrian two-bridge knot or oriented two-bridge link in standard con- tact R 3 , by showing that the upper bound given by the Kauman polyno- mial is sharp. As an application, we present a table of maximal Thurston- Bennequin numbers for prime knots with nine or fewer crossings. AMS Classication 53D12; 57M15
Chiral N-heterocyclic carbene catalyzed, enantioselective oxodiene Diels-Alder reactions with low catalyst loadings.

Chiral N-heterocyclic carbene (NHC) catalyzed redox reactions of racemic α-chloroaldehydes lead to the generation of chiral enolates suitable for highly enantioselective inverse-electron-demand 1-oxodiene Diels−Alder reactions. Significantly, these reactions proceed under mild, operationally friendly reaction conditions (EtOAc, room temperature, 2−8 h) using less than 1 mol % of a chiral N-mesityl triazolium salt as the precatalyst. A broad array of densely functionalized dihydropyran-2-ones bearing either aliphatic or aromatic substiutents are formed in excellent yields and exceptional enantioselectivities from readily available reactants. Stereochemical mismatching between the racemic starting materials and the chiral catalyst is avoided by rapid epimerization of the chloroaldehydes under the reaction conditions.
Domestic Policies, National Sovereignty, and International Economic Institutions

To what extent must nations cede control over their economic and social policies if global efe ciency is to be achieved in an interdependent world? This question is at the center of the debate over the future role of the WTO (formerly GATT) in the realm of labor and environmental standards. In this paper we establish that the market access focus of current WTO rules is well equipped to handle the problems associated with choices over labor and environmental standards. In principle, with relatively modest changes that grant governments more sovereignty, not less, these rules can deliver globally efe cient outcomes. I. INTRODUCTION To what extent must nations cede control over their economic and social policies if global efe ciency is to be achieved in an interdependent world? At a broad level, this question probes the limits of any international economic institution, whether geared toward real or e nancial concerns, that is designed to promote global efe ciency while respecting national sovereignty. Naturally, the answer depends upon the particular problem that the institution is meant to solve. In other words, the answer depends upon the inefe ciency that would arise under unilateral policy choices. At a more specie c level, this question is at the center of the debate concerning the appropriate scope of the World Trade Organization (WTO, formerly GATT). Recently, member countries have considered ways to broaden the WTO’s orientation beyond conventional trade policy measures to include labor and environmental standards. There are now initiatives to introduce the issue of labor standards directly onto the negotiating agenda of the WTO, with the purpose of creating a WTO “ social clause.” The social clause would specify a set of minimum international labor standards, and then permit restrictions to be placed against imports from countries not complying with these minimum standards. With regard to environmental policies, a WTO Committee on Trade and Environment has been established to identify the relationships between trade and environmental measures, and to
The least weight subsequence problem

The least weight subsequence (LWS) problem is introduced, and is shown to be equivalent to the classic minimum path problem for directed graphs. A special case of the LWS problem is shown to be solvable in $O(n\log n)$ time generally and, for certain weight functions, in linear time. A number of applications are given, including an optimum paragraph formation problem and the problem of finding a minimum height B-tree, whose solutions realize improvement in asymptotic time complexity.
State income taxation with mobile labor

The ability of state and local governments to use tax and other fiscal policies to redistribute income may be limited when labor is mobile. An analysis of the allocative and distributional effects of a state income tax shows that, by driving out taxed households, the burden of the tax may be shifted to immobile households and other owners of immobile factors of production and may impose an excess burden on them. The NBER TAXSIM model is used to calculate state income tax burdens for representative high-income households in 1986–1988. Further calculations based on assumed demand elasticities for labor indicate that if high-income households are mobile, the marginal excess burden of income taxes imposed on them may be of substantial size in certain states, especially among the highest income groups.
Likelihood Estimation and Inference in a Class of Nonregular Econometric Models

We study inference in structural models with a jump in the conditional density, where location and size of the jump are described by regression curves. Two prominent examples are auction models, where the bid density jumps from zero to a positive value at the lowest cost, and equilibrium job-search models, where the wage density jumps from one positive level to another at the reservation wage. General inference in such models remained a long-standing, unresolved problem, primarily due to nonregularities and computational difficulties caused by discontinuous likelihood functions. This paper develops likelihood-based estimation and inference methods for these models, focusing on optimal (Bayes) and maximum likelihood procedures. We derive convergence rates and distribution theory, and develop Bayes and Wald inference. We show that Bayes estimators and confidence intervals are attractive both theoretically and computationally, and that Bayes confidence intervals, based on posterior quantiles, provide a valid large sample inference method.
Do You Get What You Measure? Research Opportunities Based on the Veterans Health Administration Experience

SYNOPSIS: Starting in 1995, the Veterans Health Administration (VHA) transformed a bureaucratic healthcare system into a performance-driven, patient-focused integrated healthcare network. The VHA's experience may offer lessons for private and public sector providers as the U.S. explores alternative healthcare delivery systems and payment methods. Similar patient-focused integrated systems are one of the hallmarks of the latest U.S. attempt to improve the quality and efficiency of healthcare delivery. The use of performance incentives to promote cooperation and innovation is also central to both the VHA and the U.S. reform. This study reviews the VHA's experience with an eye to identifying issues and potential research avenues for accounting researchers interested in the role of accounting information for control, coordination, and organizational change.