cssi/SciSciGPT-SciSciNet huggingface dataset:
Mechanical morcellation of a solid ovarian mass in a pneumo-bag

Objectives: We present a case of a 32-year-old patient who previously underwent simple hysterectomy and bilateral pelvic sentinel lymph node biopsy for epidermoid carcinoma of the cervix. Pathology showed a 5-mm residual tumor at the cervix and the patient was referred for laparoscopic radical nerve-sparing parametrectomy and bilateral pelvic lymphadenectomy. Methods: This video shows the complete technique of the surgery, including patient and team positioning, trocar placement, and step-bystep dissection of planes, vessels, nerves, and other pelvic structures. Snapshots of the surgery with all relevant anatomic structures identified are shown during the video. Conclusions: This didactic surgical film demonstrates that parametrectomy, when systematically performed, is a reliable procedure with minimal complications.
ON THE MAXIMUM SIZE OF A (k,l)-SUM-FREE SUBSET OF AN ABELIAN GROUP

A subset A of a given finite abelian group G is called (k,l)-sum-free if the sum of k (not necessarily distinct) elements of A does not equal the sum of l (not necessarily distinct) elements of A. We are interested in finding the maximum size λk,l(G) of a (k,l)-sum-free subset in G. A (2,1)-sum-free set is simply called a sum-free set. The maximum size of a sum-free set in the cyclic group ℤn was found almost 40 years ago by Diamanda and Yap; the general case for arbitrary finite abelian groups was recently settled by Green and Ruzsa. Here we find the value of λ3,1(ℤn). More generally, a recent paper by Hamidoune and Plagne examines (k,l)-sum-free sets in G when k - l and the order of G are relatively prime; we extend their results to see what happens without this assumption.
A hybrid route choice model for dynamic traffic assignment

Network user equilibrium or user optimum is an ideal state that can hardly be achieved in real traffic. More often than not, every day traffic tends to be in disequilibrium rather than equilibrium, thanks to uncertainties in demand and supply of the network. In this paper we propose a hybrid route choice model for studying non-equilibrium traffic. It combines pre-trip route choice and en-route route choice to solve dynamic traffic assignment (DTA) in large-scale networks. Travelers are divided into two groups, habitual travelers and adaptive travelers. Habitual travelers strictly follow their pre-trip routes which can be generated in the way that major links, such as freeways or major arterial streets, are favored over minor links, while taking into account historical traffic information. Adaptive travelers are responsive to real-time information and willing to explore new routes from time to time. We apply the hybrid route choice model in a synthetic medium-scale network and a large-scale real network to assess its effect on the flow patterns and network performances, and compare them with those obtained from Predictive User Equilibrium (PUE) DTA. The results show that PUE-DTA usually produces considerably less congestion and less frequent queue spillback than the hybrid route choice model. The ratio between habitual and adaptive travelers is crucial in determining realistic flow and queuing patterns. Consistent with previous studies, we found that, in non-PUE DTA, supplying a medium sized group (usually less than 50%) of travelers real-time information is more beneficial to network performance than supplying the majority of travelers with real-time information. Finally, some suggestions are given on how to calibrate the hybrid route choice model in practice to produce realistic results.
The performance of replica control protocols in the presence of site failures

Replicated data were employed in distributed databases to enhance data availability. However, this benefit of data availability is only realized at the cost of elaborate algorithms that hide the underlying complexity of maintaining multiple copies of a single data item. The difficulty lies in keeping the copies consistent in the face of system failures while at the same time maximizing data availability. The algorithms which address these problems are called replica control algorithms. Although replica control has been the subject of extensive research for quite some time now, it has yet to fulfil its promise in practical applications. A major reason for this lack of acceptance is that the performance impact of these protocols cannot be easily quantified, as very few existing performance figures of commercial database systems which support copies are available. A natural question arises: Is replication worth it? This question is the focus of our investigation in this paper.
In vitro and in vivo effects of rifampin on Staphylococcus epidermidis graft infections.

Rifampin, bound in high concentrations to prosthetic grafts, has been proposed for the treatment of vascular graft infections. The optimum antibiotic concentration and duration of treatment for infected grafts is not known. This study compared the in vitro and in vivo efficacy of varying concentrations of rifampin against three different strains of slime producing Staphylococcus epidermidis (RP62A, KC2, and KB1) bound to knitted Dacron at high and low concentrations at l0 4 and l0 7 CFU/cm 2 of prosthetic. Time kill experiments were performed at 4, 18, and 42 hr, in which each Dacron bound bacterial strain was exposed in vitro to 4x, 64x, 100x, and 1,000x minimum inhibitory concentration (MIC) of rifampin. In vivo, the Dacron bound laboratory strain RP62A was implanted subcutaneously into the backs of male Swiss-Webster mice and exposed to 4x, 100x, and 1,000x the MIC of rifampin for similar time periods. In addition, systemic vancomycin (10 mg/kg) was assessed for synergy and prevention of rifampin resistance. In vitro, all concentrations of rifampin showed near total killing (<1 log) of all bacterial strains at low initial concentrations (10 4 CFU/cm 2 ) but not high (10 7 CFU/cm 2 ) to 42 hr. Importantly, resistance was shown to develop in all three strains of S. epidermidis with high initial bacterial biofilm concentrations. In vivo, rifampin concentrations between 4x MIC and 100x MIC achieved a balance between optimal killing and prevention of resistance. Systemic vancomycin slightly improved bacterial clearance but did not alter the development of rifampin resistance at high local concentrations. Caution is advised with the use of antibiotic bonded grafts because resistance may develop, even with the addition of systemic antibiotics.
What is ‘normative’ at cooling water intakes? Defining normalcy before judging adverse

Abstract Judgments of adverse environmental impact from cooling water intake structures need to be preceded by an appreciation of what is normal. In its report, Return to the River, the Independent Scientific Group (now called the Independent Scientific Advisory Board) — the scientific peer review arm of the Northwest Power Planning Council — advanced the notion of a ‘normative river ecosystem’ as a new conceptual foundation for salmonid recovery in the Columbia River basin. With this perspective, the sum of the best scientific understanding of how organisms and aquatic ecosystems function should be the norm or standard of measure for how we judge the effects of human activities on aquatic systems. For the best likelihood of recovery, key aspects of altered systems should be brought back toward normative (although not necessarily fully back to the historical or pristine state); new alterations should be judged for adversity by how much they move key attributes away from normative or what might be considered normal. In this paper, I ask what ‘normative’ is for the setting of cooling water intake structures and how this concept could help resolve long-standing disputes between groups interested in avoiding damage to all organisms that might be entrained or impinged and those who take a more population or community perspective for judging adverse environmental impact. In essence, I suggest that if a water intake does not move the aquatic ecosystem outside the ‘normative’ range, based on expressions of normalcy such as those discussed, then no adverse impact has occurred. Having an explicit baseline in normal or normative would place 316(b) analyses on the same conceptual foundation as 316(a) analyses, which strive to demonstrate the continuation of a balanced, indigenous community of aquatic organisms at the power station location.
South Africa's export predicament*

Using South Africa as an example, this article explores how the structure of production affects export diversification and economic growth. We show that the lagging process of structural transformation is part of the explanation for stagnant exports per capita in South Africa over the past 40 years. This slow structural transformation is shown to be a consequence in part of the peripheral nature of South Africa's productive capabilities: the country is specialized in sectors intensive in highly specific factors of production that cannot be easily redeployed to other activities. Using this methodology, we examine the sectoral priorities of the South African Department of Trade and Industry and explore the policy implications of the country's orientation in the product space.
Energy and Exergy Analysis of Gasifier-Based Coal-to-Fuel Systems

National energy security concerns related to liquid transportation fuels have revived interests in alternative liquid fuel sources. Coal-to-fuel technologies feature high efficiency energy conversion and environmental advantages. While a number of factors are driving coal-to-fuel projects forward, there are several barriers to wide commercialization of these technologies such as financial, construction, operation, and technical risks. The purpose of this study is to investigate the performance features of coal-to-fuel systems based on different gasification technologies. The target products are the Fischer-Tropsch synthetic crude and synthetic natural gas. Two types of entrained-flow gasifier-based coal-to-fuel systems are simulated and their performance features are discussed. One is a single-stage water quench cooling entrained ftow gasifier, and another one is a two-stage syngas cooling entrained-flow gasifier. The conservation of energy (first law of thermodynamics) and the quality of energy (second law of thermodynamics) for the systems are both investigated. The results of exergy analysis provide insights about the potential targets for technology improvement. The features of different gasifier-based coal-to-fuel systems are discussed. The results provide information about the research and development priorities in future.
An asymptotic optimality of the transposition rule for linear lists

The linear list is one of basic data structures in computer science with search being a primary operation defined on it. Items are located in the list by sequentially examining them from the beginning of the list. Intuitively one would like to place items that are frequently requested at the front of the list in order to minimize the number of items being examined. Given the properties of the request sequence one could place items in an order that minimizes the search cost. Yet often properties of the request sequence are either not known in advance or time dependent. Hence, it is desirable to employ self-organizing algorithms. The two best known such rules are the move-to-front and transposition rule [9, Section 6]. In addition to being simple these rules are memory-free, i.e., require no memory for their operation.
Policy Influence, Agency-Specific Expertise, and Exit in the Federal Service

Executive turnover influences agency performance, policy implementation and ultimately the success of legislative delegations. We argue that turnover intention is a function of labor market opportunities – specifically, outside employment opportunities and the acquisition of non-transferable, agency-specific human capital – as well as perceptions about the way in which political decisions have impacted federal executive influence over policymaking. Statistical evidence for these claims is provided using data from the 2007-2008 Survey on the Future of Government Service, the largest ever survey of U.S. federal executives. Agency- specific human capital drives down turnover intention in our estimates. The availability of outside options has the opposite effect except in cases where the executive has invested a lot in agency-specific human capital. Turnover intention increases when an agency’s senior executives have little influence over policy. We draw out the implications of these findings for our understanding of federal labor markets, the construction of civil service systems, and the politicization of executive branch agencies.
Reprocessing of Soft X-Ray Emission Lines in Black Hole Accretion Disks

By means of a Monte Carlo code that accounts for Compton scattering and photoabsorption followed by recombination, we investigate the radiation transfer of Lyα, Heα, and recombination continua photons of H- and He-like C, N, O, and Ne produced in the photoionized atmosphere of a relativistic black hole accretion disk. We find that photoelectric opacity causes significant attenuation of photons with energies above the O VIII K edge, that the conversion efficiencies of these photons into lower energy lines and recombination continua are high, and that accounting for this reprocessing significantly (by factors of 21%-105%) increases the flux of the Lyα and Heα emission lines of H- and He-like C and O escaping the disk atmosphere.
Sub-surface mechanical damage distributions during grinding of fused silica

Abstract The distribution and characteristics of surface cracking (i.e., sub-surface damage or SSD) formed during standard grinding processes have been measured on fused silica glass using a surface taper polishing technique. The measured SSD depth distributions are described by a single exponential followed by an asymptotic cutoff in depth. The observed surface cracks are characterized as near-surface lateral and deeper trailing indent type fractures (i.e., chatter marks). The length of the trailing indent is strongly correlated with a given grinding process. It is shown that only a small fraction of the abrasive particles are being mechanically loaded and causing fracture, and most likely it is the larger particles in the abrasive particle size distribution that bear the higher loads. The SSD depth increased with load and with a small amount of larger contaminant particles. Using a simple brittle fracture model for grinding, the SSD depth distribution has been related to the SSD length distribution to gain insight into ‘effective’ size distribution of particles participating in the fracture. Both the average crack length and the surface roughness were found to scale linearly with the maximum SSD depth. These relationships can serve as useful rules-of-thumb for non-destructively estimating SSD depth and for identifying the process that caused the SSD.
Breakup of liquid sheets and jets

Notation list Preface 1. Introduction 2. Uniform inviscid liquid sheets 3. Nonuniform inviscid liquid sheets 4. Viscous liquid sheets 5. Waves on liquid sheets 6. Phenomena of jet breakup 7. Inviscid jets 8. A viscous jet 9. Roles played by interfacial shear 10. Annular liquid jets 11. Nonlinear capillary instability of liquid jets and sheets 12. Epilogue Appendices Author index Subject Index.
Mass Outflow from the Nucleus of the Seyfert 1 Galaxy NGC 4151

We present an analysis of UV and optical spectra of NGC 4151 obtained at high spectral and angular resolutions with the Hubble Space Telescope Space Telescope Imaging Spectrograph (HST STIS). We identify a kinematic component of the emission lines that has a width of 1170 km s-1 (FWHM), intermediate between those from the broad and narrow (emission) line regions (BLRs and NLRs). We present evidence that these emission lines arise from the same gas responsible for most of the high-column UV and X-ray absorption (component "D+E") that we see in outflow at a distance of ~0.1 pc from the central nucleus. The gas in this intermediate-line region (ILR) shields the NLR and has a global covering factor of ~0.4, based on the observed C IV fluxes, indicating mass outflow over a large solid angle centered on the accretion disk's axis. A large transverse velocity (vT 2100 km s-1) compared to the radial velocity centroid (vr = -490 km s-1) indicates that the kinematics is dominated by rotation at this distance, but has a significant outflow component. The mass outflow rate at 0.1 pc is ~0.16 M☉ yr-1, which is about 10 times the accretion rate. Based on physical conditions in the gas and dynamical considerations, models that invoke magnetocentrifugal acceleration (e.g., in an accretion disk wind) are favored over those that rely on radiation driving or thermal expansion as the principal driving mechanism for the mass outflow.
Optimization of pulsed jets in crossflow

We use direct numerical simulation to study the mixing behaviour of pulsed jets in crossflow. The pulse is a square wave and the simulations consider several jet velocity ratios and pulse conditions. Our objective is to study the effects of pulsing and to explain the wide range of optimal pulsing conditions found in experimental studies of the problem. The central theme is that pulsing generates vortex rings; the effect of pulsing on transverse jets can therefore be explained by the behaviour of vortex rings in crossflow. Sau & Mahesh (J. Fluid Mech., vol. 604, 2008, pp. 389–409) show that vortex rings in crossflow exhibit three distinct flow regimes depending on stroke and ring velocity ratios. The simulations of pulsed transverse jets in this paper show that at high velocity ratios, optimal pulse conditions correspond to the transition of the vortex rings produced by pulsing between the different regimes. At low velocity ratios, optimal pulsing conditions are related to the natural time scale on which hairpin vortices form. An optimal curve in the space of stroke and velocity ratios is presented. Data from various experiments are interpreted in terms of the properties of the equivalent vortex rings and shown to collapse on the optimal curve. The proposed regime map allows the effects of experimental parameters such as pulse frequency, duty cycle, modulation and pulse energy all to be predicted by determining their effect on the equivalent stroke and velocity ratios.
The good pants homology and the Ehrenpreis Conjecture

We develop the notion of the good pants homology and show that it agrees with the standard homology on closed surfaces. (Good pants are pairs of pants whose cus have the length nearly equal to some large number R > 0.) Combined with our previous work on the Surface Subgroup Theorem, this yields a proof of the Ehrenpreis Conjecture.
Measuring Distance and Properties of the Milky Way’s Central Supermassive Black Hole with Stellar Orbits

We report new precision measurements of the properties of our Galaxy's supermassive black hole. Based on astrometric (1995-2007) and radial velocity (RV; 2000-2007) measurements from the W. M. Keck 10m telescopes, a fully unconstrained Keplerian orbit for the short-period star S0-2 provides values for the distance (R_0) of 8.0±0.6 kpc, the enclosed mass (M_(bh)) of 4.1±0.6x10^6 M☉ and the black hole's RV, which is consistent with zero with 30 km/s uncertainty. If the black hole is assumed to be at rest with respect to the Galaxy (e. g., has no massive companion to induce motion), we can further constrain the fit, obtaining R_0 = 8.4±0.4kpc and M_(bh) 4.5±0.4x10^6 M☉. More complex models constrain the extended dark mass distribution to be less than 3-4x10^5 M☉ within 0.01 pc, ~100 times higher than predictions from stellar and stellar remnant models. For all models, we identify transient astrometric shifts from source confusion (up to 5 times the astrometric error) and the assumptions regarding the black hole's radial motion as previously unrecognized limitations on orbital accuracy and the usefulness of fainter stars. Future astrometric and RV observations will remedy these effects. Our estimates of R_0 and the Galaxy's local rotation speed, which it is derived from combining R_0 with the apparent proper motion of Sgr A*, (θ_0 = 229±18 km/s), are compatible with measurements made using other methods. The increased black hole mass found in this study, compared to that determined using projected mass estimators, implies a longer period for the innermost stable orbit, longer resonant relaxation timescales for stars in the vicinity of the black hole and a better agreement with the M_(bh)-σ relation.
Initial results from the free-electron-laser master oscillator/power amplifier experiment

Abstract We describe the first master oscillator/power amplifier experiment in which both the master oscillator and power amplifier are free-electron-laser devices driven by time-sharing an electron beam from a single radiofrequency linear accelerator. The optimized, small-signal gain spectrum realized in the untapered power amplifier is presented. Up to 60% gain was observed at 3 μ with an estimated peak current of 35 A. Additional Q-switched experiments are also discussed.
Informed and automated k-mer size selection for genome assembly

Motivation: Genome assembly tools based on the de Bruijn graph framework rely on a parameter k, which represents a trade-off between several competing effects that are difficult to quantify. There is currently a lack of tools that would automatically estimate the best k to use and/or quickly generate histograms of k-mer abundances that would allow the user to make an informed decision. Results: We develop a fast and accurate sampling method that constructs approximate abundance histograms with several orders of magnitude performance improvement over traditional methods. We then present a fast heuristic that uses the generated abundance histograms for putative k values to estimate the best possible value of k. We test the effectiveness of our tool using diverse sequencing datasets and find that its choice of k leads to some of the best assemblies. Availability: Our tool KMERGENIE is freely available at: http://kmergenie.
Testing Day’s Conjecture that More Nitrogen Decreases Crop Yield Skewness

Whilecontroversysurroundsskewnessattributesoftypicalyielddistributions,abetterunderstandingis importantforagriculturalpolicyassessmentandforcrop-insuranceratesetting.Day(1965)conjectured that crop yield skewness declines with an increase in nitrogen use at low levels but not at higher levels. Employing four corn yield experimental plot datasets,we investigate the conjecture by introducing (a) a flexible Bayesian extension of the Just‐Pope technology to incorporate skewness and (b) a quantilebased measure of skewness shift. Bayesian estimation provides strong evidence in favor of negative skewnessatcommercialnitrogenratesandforDay’sconjecture.Therewasweakerevidenceinfavorof positively skewed cotton yield and little evidence in favor of the conjecture.The results are confirmed by the quantile-based measure. We also find evidence that skewness becomes more negative upon moving from corn-after-corn to corn-after-soybean.
N‐Heterocyclic‐Carbene‐Catalyzed Synthesis of 2‐Aryl Indoles

A convergent and efficient transition-metal-free catalytic synthesis of 2-aryl-indoles has been developed. The interception of a highly reactive and transient aza-ortho-quinone methide by an acyl anion equivalent generated through N-hetereocyclic carbene catalysis is central to this successful strategy. High yields and a wide scope as well as the streamlined synthesis of a kinase inhibitor are reported.
Warped AdS3/dipole-CFT duality

String theory contains solutions with $ {\text{SL}}\left( {{2},\mathbb{R}} \right){\text{R}} \times {\text{U}}{\left( {1} \right)_L} $ -invariant warped AdS3 (WAdS3) factors arising as continuous deformations of ordinary AdS3 factors. We propose that some of these are holographically dual to the IR limits of nonlocal dipole-deformed 2D D-brane gauge theories, referred to as “dipole CFTs”. Neither the bulk nor boundary theories are currently well-understood, and consequences of the proposed duality for both sides is investigated. The bulk entropy-area law suggests that dipole CFTs have (at large N) a high-energy density of states which does not depend on the deformation parameter. Putting the boundary theory on a spatial circle leads to closed timelike curves in the bulk, suggesting a relation of the latter to dipole-type nonlocality.
Virtual environment display system

A head-mounted, wide-angle, stereoscopic display system controlled by operator position, voice and gesture has been developed for use as a multipurpose interface environment. The system provides a multisensory, interactive display environment in which a user can virtually explore a 360-degree synthesized or remotely sensed environment and can viscerally interact with its components. Primary applications of the system are in telerobotics, management of large-scale integrated information systems, and human factors research. System configuration, application scenarios, and research directions are described.
Chiral Luttinger liquids at the fractional quantum Hall edge

The edges of quantum Hall fluids behave as one-dimensional conductors. This article reviews electron transport into these edge states, covering both the theory based on the chiral Luttinger liquid and the experimental findings using electron tunneling as the probe. The first part of the review presents a basic description of this theory, including a derivation of the density of states, to provide a framework and language for discussing the experimental observations. The signature of the chiral Luttinger liquid is a power-law behavior for the density of states and the tunneling conductances. Experimentally, two techniques have been applied to study the tunneling conductance, using a gated point contact between two quantum Hall edges, or using a cleaved-edge barrier between an edge and a normal conductor. The point-contact method exhibits resonant tunneling, which appears to show some aspects of the Luttinger liquid, and the cleaved-edge method has yielded clear power-law dependences in the off-resonance conductances. Power-law behavior over many orders of magnitude is observed, confirming the Luttinger-liquid character of the edge states. However, the power-law exponents, while in agreement with finite-size numerical calculations, can differ from the universal values predicted by the Chern-Simon field theory. This disagreement is still not well understood. The review concludes with a brief survey of other one-dimensional conductors that have been studied to look for characteristics of the nonchiral Tomonaga-Luttinger liquid.
A dynamic generalization of Becker's assortative matching result

Abstract This paper considers a dynamic matching model in which each agent's future productivity depends in part on their current match, as in labor markets, schooling, intergenerational marriage markets, and other environments. The Planner's endogenous rankings of human distributions are characterized. These Planner rankings are then used to develop sufficient conditions for positive assortative matching to be dynamically efficient. One lesson that emerges is that complementarity assumptions alone are insufficient for a robust sorting theory — the curvature of the static production function is also critical to determine optimal sorting patterns. In addition, the Planner's ranking of distributions over human capital yield characterizations of individual attitudes toward human capital gambles in an associated market equilibrium. Finally, the implied dynamics for (1) individual wages and (2) wage distributions across age cohorts are characterized.
The breakdown of the anelastic approximation in rotating compressible convection: implications for astrophysical systems

The linear theory for rotating compressible convection in a plane layer geometry is presented for the astrophysically relevant case of low Prandtl number gases. When the rotation rate of the system is large, the flow remains geostrophically balanced for all stratification levels investigated and the classical (i.e. incompressible) asymptotic scaling laws for the critical parameters are recovered. For sufficiently small Prandtl numbers, increasing stratification tends to further destabilize the fluid layer, decrease the critical wavenumber and increase the oscillation frequency of the convective instability. In combination, these effects increase the relative magnitude of the time derivative of the density perturbation contained in the conservation of mass equation to non-negligible levels; the resulting convective instabilities occur in the form of compressional quasi-geostrophic oscillations. We find that the anelastic equations, which neglect this term, cannot capture these instabilities and possess spuriously growing eigenmodes in the rapidly rotating, low Prandtl number regime. It is shown that the Mach number for rapidly rotating compressible convection is intrinsically small for all background states, regardless of the departure from adiabaticity.
The Gender Revolution: Uneven and Stalled

In this article, the author describes sweeping changes in the gender system and offers explanations for why change has been uneven. Because the devaluation of activities done by women has changed little, women have had strong incentive to enter male jobs, but men have had little incentive to take on female activities or jobs. The gender egalitarianism that gained traction was the notion that women should have access to upward mobility and to all areas of schooling and jobs. But persistent gender essentialism means that most people follow gender-typical paths except when upward mobility is impossible otherwise. Middle-class women entered managerial and professional jobs more than working-class women integrated blue-collar jobs because the latter were able to move up while choosing a “female” occupation; many mothers of middle-class women were already in the highest-status female occupations. The author also notes a number of gender-egalitarian trends that have stalled.
A suggestion of a connection between radio fading and small fluctuations in the Earth's magnetic field

The fading of radio signals has been referred to time and again as an interference effect. The suggestion that the upper atmosphere may be an important factor in enabling electromagnetic waves to propagate over appreciable distances has been the origin and support of this view. The wave traveling along the ground and the wave arriving by reflection have been supposed to interfere. Within the last few years, however, it has become obvious that more than simple interference is involved. Thus short-wave transmission, i.e., transmission on wave-lengths below 100 meters in length, showed in the hands of Taylor and Hulburt that beyond a certain range signals are received entirely by an overhead route. In spite of this fact, the signals show fading.
Internal chip ESD phenomena beyond the protection circuit

Input/output electrostatic discharge (ESD) circuit requirements call for good protection of the pin with respect to both the ground and the power bus pins. Although effective protection can be designed at the pin many cases of damage phenomena are known to occur internal to the chip beyond the protection circuit. Here, the issues of protection between V/sub DD/ and V/sub SS/ are discussed first. This is followed by examples of how protection circuit performance can be sensitive to internal chip layout, independent of its effective design. Several illustrative actual case studies are reported to emphasize the internal chip ESD phenomena and their adverse effects. >
Pentaquark Searches in Electron-Positron Annihilations and Two-Photon Collisions at LEP

Evidence for the production of exotic hadron states composed of five quarks (pentaquarks) has been searched for in data collected by the ALEPH, DELPHI, and L3 experiments at LEP. No significant signal is observed. Several 95% C.L. upper limits are set on the production rates of such particles.
Stochastic Equations with Time-Dependent Drift Driven by Levy Processes

The stochastic equation dXt=dSt+a(t,Xt)dt, t≥0, is considered where S is a one-dimensional Levy process with the characteristic exponent ψ(ξ),ξ∈ℝ. We prove the existence of (weak) solutions for a bounded, measurable coefficient a and any initial value X0=x0∈ℝ when (ℛe ψ(ξ))−1=o(|ξ|−1) as |ξ|→∞. These conditions coincide with those found by Tanaka, Tsuchiya and Watanabe (J. Math. Kyoto Univ. 14(1), 73–92, 1974) in the case of a(t,x)=a(x). Our approach is based on Krylov’s estimates for Levy processes with time-dependent drift. Some variants of those estimates are derived in this note.
Mobile phone coverage and producer markets : evidence from West Africa

Mobile phone coverage has expanded considerably throughout the developing world, particularly within sub-Saharan Africa. Existing evidence suggests that increased access to information technology has improved agricultural market efficiency for consumer markets and certain commodities, but there is less evidence of its impact on producer markets. Building on the work of Aker (2010), this paper estimates the impact of mobile phone coverage on producer price dispersion for three commodities in Niger. The results suggest that mobile phone coverage reduces spatial producer price dispersion by 6 percent for cowpea, a semi-perishable commodity. These effects are strongest for remote markets and during certain periods of the year. The introduction of mobile phone coverage has no effect on producer price dispersion for millet and sorghum, two staple grains that are less perishable and are commonly stored by farmers. There are no impacts of mobile phone coverage on traders' gross margins or producer price levels, but mobile phone coverage is associated with a reduction in the intra-annual price variation for cowpea. These results are potentially explained by the fact that farmers engage in greater storage for storable commodities such as millet and sorghum.
Adaptive control of discrete-time systems using multiple models

The adaptive control of a linear time-invariant discrete-time system using multiple models is considered in this paper. Both the deterministic (noise free) case and the stochastic case when random disturbances are present are discussed. Based on the prediction errors of a finite number of fixed and adaptive identification models, a procedure is outlined for switching between a finite number of controllers to improve performance. The principal contributions of the paper are the proof of global stability of the overall system and the convergence of the tracking error signal to zero in the deterministic case and the proof of convergence of the minimum variance control problem. Computer simulation results are included to complement the theoretical results.
Predicting the Expected Behavior of Agents that Learn About Agents: The CLRI Framework

We describe a framework and equations used to model and predict the behavior of multi-agent systems (MASs) with learning agents. A difference equation is used for calculating the progression of an agent's error in its decision function, thereby telling us how the agent is expected to fare in the MAS. The equation relies on parameters which capture the agent's learning abilities, such as its change rate, learning rate and retention rate, as well as relevant aspects of the MAS such as the impact that agents have on each other. We validate the framework with experimental results using reinforcement learning agents in a market system, as well as with other experimental results gathered from the AI literature. Finally, we use PAC-theory to show how to calculate bounds on the values of the learning parameters.
Bisections of graphs

A bisection of a graph is a bipartition of its vertex set in which the number of vertices in the two parts differ by at most 1, and its size is the number of edges which go across the two parts. In this paper, motivated by several questions and conjectures of Bollobas and Scott, we study maximum bisections of graphs. First, we extend the classical Edwards bound on maximum cuts to bisections. A simple corollary of our result implies that every graph on n vertices and m edges with no isolated vertices, and maximum degree at most n/3+1, admits a bisection of size at least m/2+n/6. Then using the tools that we developed to extend [email protected]?s bound, we prove a judicious bisection result which states that graphs with large minimum degree have a bisection in which both parts span relatively few edges. A special case of this general theorem answers a conjecture of Bollobas and Scott, and shows that every graph on n vertices and m edges of minimum degree at least 2 admits a bisection in which the number of edges in each part is at most (1/3+o(1))m. We also present several other results on bisections of graphs.
Wedded Bliss or Tainted Love? Stock Market Reactions to the Introduction of Cobranded Products

We examine whether cobranding—the practice of using two established brand names on the same product— increases the market value of parent firms. Using data from the consumer packaged goods industry, we document that the average stock market reaction to the announcement of cobranded new products is approximately C1.0%. We hypothesize that this reaction is significantly higher than it would have been if these same products were single branded, and we find evidence consistent with this hypothesis. We also examine the determinants of this stock market reaction. We find that the consistency between the two brand images, the innovativeness of the product, and the exclusivity of the cobranding relationship significantly increase the market reaction to cobranding announcements. Our findings provide important managerial guidelines for enhancing firm value through cobranding partnerships.
Perceptual-based image fusion for hyperspectral data

Three hierarchical multiresolution image fusion techniques are implemented and tested using image data from the Airborne Visual/Infrared Imaging Spectrometer (AVIRIS) hyperspectral sensor. The methods presented focus on combining multiple images from the AVIRIS sensor into a smaller subset of images white maintaining the visual information necessary for human analysis. Two of the techniques are published algorithms that were originally designed to combine images from multiple sensors, but are shown to work well on multiple images from the same sensor. The third method presented was developed specifically to fuse hyperspectral images for visual analysis. This new method uses the spatial frequency response (contrast sensitivity) of the human visual system to determine which features in the input images need to be preserved in the composite image(s) thus ensuring the composite image maintains the visually relevant features from each input image. The image fusion algorithms are analyzed using test images with known image characteristics and image data from the AVIRIS hyperspectral sensor. After analyzing the signal-to-noise ratios and visual aesthetics of the fused images, contrast sensitivity based fusion is shown to provide excellent fusion results and, in every case, outperformed the other two methods.
MEDIATORS AND MECHANISMS OF CHANGE IN PSYCHOTHERAPY RESEARCH

There has been enormous progress in psychotherapy research. This has culminated in recognition of several treatments that have strong evidence in their behalf. Even so, after decades of psychotherapy research, we cannot provide an evidence-based explanation for how or why even our most well studied interventions produce change, that is, the mechanism(s) through which treatments operate. This chapter presents central requirements for demonstrating mediators and mechanisms of change and reviews current data-analytic and designs approaches and why they fall short of meeting these requirements. The role of the therapeutic alliance in psychotherapy and cognitive changes in cognitive therapy for depression are highlighted to illustrate key issues. Promising lines of work to identify mediators and mechanisms, ways of bringing to bear multiple types of evidence, recommendations to make progress in understanding how therapy works, and conceptual and research challenges in evaluating mediators and mechanisms are also presented.
Approximation algorithms and hardness of the k-route cut problem

We study the k-route cut problem: given an undirected edge-weighted graph G = (V, E), a collection {(s1, t1), (s2, t2),..., (sr, tr)} of source-sink pairs, and an integer connectivity requirement k, the goal is to find a minimum-weight subset E' of edges to remove, such that the connectivity of every pair (si, ti) falls below k. Specifically, in the edge-connectivity version, EC-kRC, the requirement is that there are at most (k − 1) edge-disjoint paths connecting si to ti in G\E', while in the vertex-connectivity version, VC-kRC, the same requirement is for vertex-disjoint paths. Prior to our work, poly-logarithmic approximation algorithms have been known for the special case where k ≤ 3, but no non-trivial approximation algorithms were known for any value k > 3, except in the single-source setting. We show an O(k log3/2r)-approximation algorithm for EC-kRC with uniform edge weights, and several polylogarithmic bi-criteria approximation algorithms for EC-kRC and VC-kRC, where the connectivity requirement k is violated by a constant factor. We complement these upper bounds by proving that VC-kRC is hard to approximate to within a factor of ke for some fixed e > 0.We then turn to study a simpler version of VC-kRC, where only one source-sink pair is present. We give a simple bi-criteria approximation algorithm for this case, and show evidence that even this restricted version of the problem may be hard to approximate. For example, we prove that the single source-sink pair version of VC-kRC has no constant-factor approximation, assuming Feige's Random κ-AND assumption.
Waking up dormant tumors

As appreciation grows for the contribution of the tumor microenvironment to the progression of cancer, new evidence accumulates to support that the participation of stromal cells can extend beyond the local environment. Recently, Elkabets and colleagues demonstrated a systemic interaction between cancer cells and distant bone marrow cells to support the growth of otherwise indolent tumor cells at a secondary site, raising thought-provoking questions regarding the involvement of stromal cells in maintaining metastatic dormancy.
Photoexcitation of Si-Si Radiative Surface States in Nanocrystallites

Recently, intrinsic localized excitonic radiative surface states belonging to interacting dangling bonds of expanded, unstrained Si-Si dimers on the surface of nanocrystallites have been predicted. Those are connected, via a potential barrier, to the nonradiative delocalized excitonic states on the unexpanded, strained dimer. We present a theoretical analysis of the photoexcitation pathways involved in populating the radiative states. We include both direct above barrier, and indirect excitation from the photoexcited delocalized excitonic states via quantum tunneling and thermal activation. Our calculation gives an enhancement in the efficiency for sizes below a critical size of 1.4 nm, the size for which the outer trapped states become stable against tunneling and thermal activation. It is as if the material were changed from an indirect gap to a somewhat direct gap material. The results show that the photoluminescence exhibits a large Stokes shift resulting from the expansion of the radiative dimers. Moreover, the emission bandwidth is found to be quite wide especially for the ultra small crystallites (0.8 nm) where it encompasses nearly all of the visible spectrum, and the near infrared. Spectra simulated over size distributions are presented.
Representations of polygons of finite groups

We construct discrete and faithful representations into the isometry group of a hyperbolic space of the fundamental groups of acute negatively curved evensided polygons of finite groups.
The cluster problem revisited

In continuous branch-and-bound algorithms, a very large number of boxes near global minima may be visited prior to termination. This so-called cluster problem (J Glob Optim 5(3):253---265, 1994) is revisited and a new analysis is presented. Previous results are confirmed, which state that at least second-order convergence of the relaxations is required to overcome the exponential dependence on the termination tolerance. Additionally, it is found that there exists a threshold on the convergence order pre-factor which can eliminate the cluster problem completely for second-order relaxations. This result indicates that, even among relaxations with second-order convergence, behavior in branch-and-bound algorithms may be fundamentally different depending on the pre-factor. A conservative estimate of the pre-factor is given for $$\alpha $$ BB relaxations.
Policy-based network management for generalized vehicle-to-internet connectivity

Over the past year and a half we have operated a vehicle-to-Internet solution that provides WiFi connectivity to passenger buses. While operating this service we have found it difficult to centrally manage network resources despite multiple low level tools being available. For this reason we propose the WiRover Policy Framework which provides a unified, centralized solution to manage and control network resources. Further, we propose a simple syntax with which users and administrators can express their network control preferences. We believe that centralized control of network resources will simplify the management of vehicle-to-Internet connectivity and will enable new forms of connectivity models to develop.
Interpretation and generalization of score matching

Score matching is a recently developed parameter learning method that is particularly effective to complicated high dimensional density models with intractable partition functions. In this paper, we study two issues that have not been completely resolved for score matching. First, we provide a formal link between maximum likelihood and score matching. Our analysis shows that score matching finds model parameters that are more robust with noisy training data. Second, we develop a generalization of score matching. Based on this generalization, we further demonstrate an extension of score matching to models of discrete data.
C-H hydroxylation using a heterocyclic catalyst and aqueous H2O2.

Substituierte Benzoxathiazine wirken als Katalysatoren fur die selektive Hydroxylierung tertiarer C-H-Bindungen. Mechanistische Studien offenbaren eine unerwartete Abweichung zwischen der Reaktivitat der Oxaziridine und ihrer katalytischen Aktivitat und fuhrten zur Entwicklung eines neuen Katalysators, der solche Reaktionen in wassrigem H2O2 vermittelt (siehe Schema).
Delay test generation for synchronous sequential circuits

The author presents a method for generating test sequences to detect delay faults in sequential circuits using the stuck-at-fault sequential test generator STALLION. The method is complete in that it will generate a delay test sequence for a targeted fault given sufficient CPU time, if such a sequence exists. Faults for which no delay test sequence exists are termed sequentially delay redundant. The author describes means of eliminating sequential delay redundancies in logic circuits. He presents a partial-scan methodology for enhancing the testability of difficult-to-test or untestable sequential circuits, wherein a small number of flip-flops are selected and made controllable/observable. The selection process guarantees the elimination of all sequential delay redundancies. It is shown that an intimate relationship exists between state assignment and delay testability of a sequential machine. A state assignment algorithm for the synthesis of sequential machines with maximal delay fault testability is described. Preliminary experimental results using the test generation, partial-scan, and synthesis algorithms are presented. >