cssi/SciSciGPT-SciSciNet huggingface dataset:
Value and Risk: Beyond Betas

Risk can be both a threat to a company’s financial health and an opportunity to get ahead of the competition. Most analysts, when referring to risk management, focus on the threat and emphasize protecting against that threat (i.e., risk hedging). The risk associated with an investment is generally reflected in the discount rate used in conventional discounted cash flow models, and because analysts also assume that only market risk affects discount rates, the firms that spend time and resources on hedging company-specific risk may well lose value. But risk management can increase firm value—by altering investment policy and creating competitive advantages, which can have consequences for expected growth rates and excess returns.
Twenty Years of SUGRA

A brief summary is given of the developments of mSUGRA and its extensions since the formulation of these models in 1982. Future directions and prospects are also discussed.
On the sample complexity of learning Bayesian networks

In recent years there has been an increasing interest in learning Bayesian networks from data. One of the most effective methods for learning such networks is based on the minimum description length (MDL) principle. Previous work has shown that this learning procedure is asymptotically successful: with probability one, it will converge to the target distribution, given a sufficient number of samples. However, the rate of this convergence has been hitherto unknown. In this work we examine the sample complexity of MDL based learning procedures for Bayesian networks. We show that the number of samples needed to learn an e-close approximation (in terms of entropy distance) with confidence δ is O ((1/e)4/3 log 1/e log 1/δ log log 1/δ). This means that the sample complexity is a low-order polynomial in the error threshold and sub-linear in the confidence bound. We also discuss how the constants in this term depend on the complexity of the target distribution. Finally, we address questions of asymptotic minimality and propose a method for using the sample complexity results to speed up the learning process.
Extraplanar Dust in Spiral Galaxies: Observations and Implications

Recent optical and submillimeter observations have begun to probe the existence of dust grains in the halos of spiral galaxies. I review our own work in this area which employs high-resolution optical images of edge-on spiral galaxies to trace high-z dust in absorption against the background stellar light of the galaxies. We have found that a substantial fraction of such galaxies (> 50%) show extensive webs of dust-bearing clouds to heights z > 2 kpc. Extraplanar dust in galaxies is statistically correlated with extraplanar diffuse ionized gas, though there is no evidence for a direct, physical relationship between these two phases of the high-z interstellar medium. The dense high-z clouds individually have masses estimated to be ≳105–106 M ⊙. The detailed properties of the observed dust structures suggest the clouds seen in our images may represent the dense phase of a multiphase ISM at high-z. Such dense clouds can have an important effect on the observed light distribution in spiral galaxies. I discuss the effects such high-z dust can have on quantitative measures of the vertical structure of stars and ionized gas in edge-on systems.
Dynamical Approach to Pair Production from Strong Fields

In relativistic heavy-ion collisions one is hoping to produce conditions where energy densities are high enough so that a new state of matter-the quark-gluon plasma can be produced. This state of matter lasts for a short period of time following the collision and may or may not be in equilibrium. Following this phase a transition to ordinary hadronic matter takes place and many of the processes which occur during the quark-gluon plasma phase might be masked by processes which occur in the hadronic phase. In order to determine processes which might be signals of the quark gluon plasma one needs to know the dynamical evolution of the plasma. This is because the particles that get produced during that phase have to travel through a time evolving plasma. In order to study this problem one needs a different way of thinking about field theory. Traditionally experiments in Elementary Particle Physics are black box experiments where initial particles enter a region, final particles exit the experimental region and all that is asked is how many particles of what type, energy, etc. enter various detectors. This type of experiment requires only a covariant S-Matrix theory to predict the probabilities to be expected in the detectors. However, if we want to know signatures of the quark gluon plasma, we actually need to follow the time evolution of the plasma and fields produced following the heavy ion collision. This requires a non-covariant real time formalism for the time evolution of the quantum fields. In these talks we would first like to discuss various formalisms for doing real time calculations in quantum field theory and then study in detail a very simplified model of the production of the quark-gluon plasma-Schwinger’s mechanism for Pair-production from strong “classical” gauge fields.
Building results frameworks for safety nets projects

Results chains are useful tools to clarify safety nets programs' objectives, verify the program internal logic, and guide the selection of indicators. Although the recent trend has been to focus mostly on outcome indicators, indicators are needed at all levels of the results chain to better understand program performance. Ideally, safety nets performance monitoring systems should build upon reliable program records and be complemented with a combination of tailor?made data sources and national surveys. The latter should be considered not only for monitoring purposes but within a program evaluation agenda. In any case, it is very important that adequate resources and technical assistance are channeled to strengthen institutional capacity for safety nets results-based management.
Formation of Bulges

Bulges, often identified with the spheroidal component of a galaxy, have a complex pedigree. Massive bulges are generally red and old, but lower mass bulges have broader dispersions in color that may be correlated with disk colors. This suggests different formation scenarios. I will review possible formation sequences for bulges, describe the various signatures that distinguish these scenarios, and discuss implications for the high redshift universe.
Loop-erased walks and total positivity

We consider matrices whose elements enumerate weights of walks in planar directed weighted graphs (not necessarily acyclic). These matrices are totally nonnegative; more precisely, all their minors are formal power series in edge weights with nonnegative coefficients. A combinatorial explanation of this phenomenon involves loop-erased walks. Applications include total positivity of hitting matrices of Brownian motion in planar domains.
Evolution of Ecological Dominance of Yeast Species in High-Sugar Environments

In budding yeasts, fermentation in the presence of oxygen evolved around the time of a whole genome duplication (WGD) and is thought to confer dominance in high-sugar environments because ethanol is toxic to many species. Although there are many fermentative yeast species, only Saccharomyces cerevisiae consistently dominates wine fermentations. In this study, we use coculture experiments and intrinsic growth rate assays to examine the relative fitness of non-WGD and WGD yeast species across environments to assess when S. cerevisiae’s ability to dominate high-sugar environments arose. We show that S. cerevisiae dominates nearly all other non-WGD and WGD species except for its sibling species S. paradoxus in both grape juice and a high-sugar rich medium. Of the species we tested, S. cerevisiae and S. paradoxus have evolved the highest ethanol tolerance and intrinsic growth rate in grape juice. However, the ability of S. cerevisiae and S. paradoxus to dominate certain species depends on the temperature and the type of high-sugar environment. Our results indicate that dominance of high-sugar environments evolved much more recently than the WGD, most likely just prior to or during the differentiation of Saccharomyces species, and that evolution of multiple traits contributes to S. cerevisiae's ability to dominate wine fermentations.
Transitions to Capitalism in Early Modern Europe

List of illustrations Preface Part I: 1. Themes and theories 2. Medieval legacies Part II: Introduction: the long sixteenth century 3. Agriculture: growth and the limits of development 4. Artisans and entrepreneurs Part III: Introduction: crisis and recovery: towards capitalist industrialization 5. Agricultural disparity and development 6. The golden age of rural industry Part IV: 7. Experiences of labor in the era of transitions Epilogue: transitions and traditions Index.
The limits to wage-led growth in a low-income economy

Neo-Kaleckian literature has actively debated whether growth is wage- or profit-led in capitalist economies. However, existing studies tend to ignore the non-tradable sector and heterogeneity within the tradable sector. This article shows that incorporating these features renders wage-led growth in an open developing economy unfeasible in the traditional (Kaleckian) sense of the term. This result—which follows even if one sets aside the competitiveness considerations generally seen as impeding such growth—occurs due to the presence of a homogeneous goods-producing tradable sector that sets the ceiling to steady-state growth. A corollary, in light of findings from the ‘new new trade theory’ literature, is that increasing South-South trade may tend to narrow room for wage-led growth regardless of the other desirable effects of higher wages.
How substitutable are fixed factors in production? evidence from pre-industrial England

Whether fixed factors such as land constrain per-capita income growth depends crucially on two variables: the substitutability of fixed factors in production, and the extent to which innovation is biased towards land-saving technologies. This paper attempts to quantify both. Using the timing of plague epidemics as an instrument for labor supply, I estimate the elasticity of substitution between fixed and non-fixed factors in pre-industrial England to be significantly less than one. In addition, I find evidence that denser populations – and hence higher land scarcity – induced innovation towards land-saving technologies.
Combinatorial insights into doping control and transport properties of zinc tin nitride

ZnSnN2 is an Earth-abundant semiconductor analogous to the III–nitrides with potential as a solar absorber due to its direct bandgap, steep absorption onset, and disorder-driven bandgap tunability. Despite these desirable properties, discrepancies in the fundamental bandgap and degenerate n-type carrier density have been prevalent issues in the limited amount of literature available on this material. Using a combinatorial RF co-sputtering approach, we have explored a growth-temperature-composition space for Zn1+xSn1−xN2 over the ranges 35–340 °C and 0.30–0.75 Zn/(Zn + Sn). In this way, we identified an optimal set of deposition parameters for obtaining as-deposited films with wurtzite crystal structure and carrier density as low as 1.8 × 1018 cm−3. Films grown at 230 °C with Zn/(Zn + Sn) = 0.60 were found to have the largest grain size overall (70 nm diameter on average) while also exhibiting low carrier density (3 × 1018 cm−3) and high mobility (8.3 cm2 V−1 s−1). Using this approach, we establish the direct bandgap of cation-disordered ZnSnN2 at 1.0 eV. Furthermore, we report tunable carrier density as a function of cation composition, in which lower carrier density is observed for higher Zn content. This relationship manifests as a Burstein–Moss shift widening the apparent bandgap as cation composition moves away from Zn-rich. Collectively, these findings provide important insight into the fundamental properties of the Zn–Sn–N material system and highlight the potential to utilize ZnSnN2 for photovoltaics.
A Replication of 'Do Voters Affect or Elect Policies? Evidence from the U.S. House' (The Quarterly Journal of Economics, 2004)

I replicate Lee, Moretti, and Butler (2004) "Do Voters Affect or Elect Policies? Evidence from the US House." Quarterly Journal of Economics, 119(3), 807-59, using new advances in regression discontinuity design methodology. Specifically, I use local linear regression with optimal bandwidths (Imbens and Kalyanaraman, 2012) and I follow advice on polynomial modelling in Lee and Lemieux (2010). I also run McCrary (2008)'s density test as an additional robustness check to investigate sorting around the treatment cut-off. I investigate the sensitivity of estimates to polynomial order, bandwidth, and to the inclusion of covariates. The conclusion of Lee, Moretti, and Butler (2004) that voters "elect" rather than "affect" policies still holds under this more rigorous scrutiny.
Local Matters: Internationalizing Strategies for U.S. Law Firms

The local nature of legal systems reduces the harmonizing impact that globalization has generated in other sectors of the economy. Despite the continuing importance of local differences and institutions, the world in which law and lawyers operate is increasingly connected, and national borders are receding as barriers to commerce. Lawyers and their firms must respond to the forces of globalization both as organizations and in connection with the services they provide. This article addresses the ways in which they are doing so by examining what it means for a law firm to be both a global and a U.S. firm. The article begins with a brief historical review and, in Section I, a discussion of the changes made by U.S. firms in their transformations to global competitors. Section II continues this historical review but broadens the focus from firms to include lawyers as well. Finally, Section III considers the credentials of lawyers active in the international legal services market. The analysis is based on two ongoing empirical studies, one of which examines the credentials of lawyers working in the foreign offices of U.S. law firms and the other focusing on foreign law graduates who earn a U.S. law school LL.M. degree, the one-year post-J.D. degree aimed at foreign law graduates. The article concludes with some thoughts on the challenges facing U.S.-based firms as they respond to globalization by adding local lawyers to their rosters and local advisory services to their offerings. In becoming more local, the firms must struggle to maintain and redefine their U.S. identities.
A Quantitative Analysis of China's Structural Transformation

Abstract The structural transformation of China – or the reallocation of resources from the agricultural sector to the nonagricultural sector – between 1978 and 2003 was truly remarkable. We develop a two-sector neoclassical growth model to quantitatively assess the driving forces of China's recent structural transformation. In addition to the forces currently emphasized in the literature–sectoral productivity growth—we show that China's transformation was accelerated significantly by the gradual reduction in the relative size of the Chinese government. We find that the reduction in the size of the Chinese government accounted – by itself – for 15% of the reduction in the agricultural share of employment. Two mechanisms explain this: (i) in our model the lower tax rate associated with reduced intervention encouraged the accumulation of physical capital, which is produced in the nonagricultural sector; (ii) lower inefficiencies induced incomes to rise and, given our preferences, resulted in a disproportionate increase in the demand for the nonagricultural good.
Dynamics of pipes conveying fluid with non-uniform turbulent and laminar velocity profiles

Previous analytical work on stability of fluid-conveying pipes assumed a uniform velocity profile for the conveyed fluid. In real fluid flows, the presence of viscosity leads to a sheared region near the wall. Earlier studies correctly note that viscous forces do not affect the dynamics of the system since these forces are balanced by pressure drop in the conveyed fluid. Although viscous shear has not been ignored in these studies, a uniform velocity profile assumes that the sheared region is infinitely thin. Prior analysis was extended to account for a fully developed non-uniform profile such as would be encountered in real fluid flows. A modified, highly tractable equation of motion was derived, which includes a single additional parameter to account for the true momentum of the fluid. This empirical parameter was determined by numerical analysis over the Reynolds number range of interest. The stability of cantilever pipes conveying fluid with two types of non-uniform velocity profile was assessed. In the first case, the profile was a function of Reynolds number and transition to turbulence occurred before the onset of flutter instability. This case had stability properties similar to the uniform velocity case except in specific narrow regions of the parameter space. The second case required that the Reynolds number be such that the flow was always laminar. For this case, lower fluid velocity was required to achieve instability, and the oscillation frequency at instability was considerably lower over much of the parameter space, compared to the uniform case.
Role of cyclic AMP in the action of antidiuretic hormone on kidney.

Publisher Summary This chapter describes the role of cyclic AMP in the action of antidiuretic hormone on kidney. The initial steps in the action of ADH involve hormonal stimulation of cyclic AMP formation from ATP. An ADH receptor within the plasma membrane is assumed to be associated with adenylate cyclase, and the hormone–receptor interaction leads to an increase in cyclic AMP formation. There are few direct studies on the interaction of ADH with its renal receptor. Studies on the stimulation of renal medullary adenylate cyclase by vasopressin and its naturally occurring as well as artificial chemical analogs have indicated that the renal ADH receptor displays a high degree of specificity for this class of polypeptides and that renal medullary adenylate cyclase was always most sensitive to the naturally occurring variety of ADH. A marked parallelism has been found between the ability of ADH and its structural analogs to produce an antidiuretic effect in vivo and the dose of the hormone required for half maximal stimulation of renal medullary adenylate cyclase in vitro, but there was no close relationship to the maximal stimulatory capacity.
Quantum Gravity: a Progress Report

The problem of reconciling general relativity and quantum theory has fascinated and bedeviled physicists for more than 70?years. Despite recent progress in string theory and loop quantum gravity, a complete solution remains out of reach. I review the status of the continuing effort to quantize gravity, emphasizing the underlying conceptual issues and the various attempts to come to grips with them.
Correlation between oxide breakdown and defects in SiC wafers

A correlation between gate oxide breakdown in metal oxide semiconductor (MOS) capacitor structures and structural defects in SiC wafers is reported. The oxide breakdown under high applied fields, in the accumulation regime of the MOS capacitor structure, is observed to occur at locations corresponding to the edge of bulk structural defects in the SiC wafer such as polytype inclusions, regions of crystallographic misorientation, or different doping concentration. Breakdown measurements on more than 50 different MOS structures did not indicate any failure of the oxide exactly above a micropipe. The scatter in the oxide breakdown field across a 10 mm × 10 mm square area was about 50%, and the highest breakdown field obtained was close to 8 MV/cm.
Methylenations of heteroatom-substituted carbonyls with dimethyl titanocene

Abstract Reaction of dimethyl titanocene with a variety of heteroatom-substituted carbonyl compounds, including: silylesters, anhydrides, carbonates, amides, imides, thioesters, selenoesters and acyl silanes gives the corresponding heteroatom-substituted alkenes.
Convergent, asymmetric synthesis of vicinal amino alcohols via Rh-catalyzed addition of α-amido trifluoroborates to carbonyls

We describe the Rh-catalyzed addition of α-sulfinamido trifluoroborates to carbonyl compounds for the convergent, asymmetric synthesis of vicinal amino alcohols. This method represents the first application of α-amino boron reagents as reaction partners in rhodium-catalyzed couplings. Reactions with trifluoromethyl ketones proceed in reasonable yields and with good diastereoselectivity along with complete retention at the organoboron stereocenter. The potential of this method is further highlighted by the exploration of a variety of nitrogen substituents and addition to benzaldehyde and trityl-protected isatin.
Reduction of the 1-(4-thiomethylphenyl)-2,2,2-trifluoroethyl carbocation by sodium sulfite

Abstract The rate of the reaction of sodium sulfite with 1-(4-thiomethylphenyl)-2,2,2-trifluoroethyl bromide in 20% acetonitrile in water is kinetically zero-order in sulfite anion and at 0.27 M SO 3 2− the reaction gives a 0.67:0.15:0.18 ratio of the C-1 sulfite adduct, the water adduct and the novel reduction product 1-(4-thiomethylphenyl)-2,2,2-trifluoroethane, respectively.
Fast Multiple-Splitting Algorithms for Convex Optimization

We present in this paper two different classes of general multiple-splitting algorithms for solving finite-dimensional convex optimization problems. Under the assumption that the function being minimized can be written as the sum of $K$ convex functions, each of which has a Lipschitz continuous gradient, we prove that the number of iterations needed by the first class of algorithms to obtain an $\epsilon$-optimal solution is $O((K-1)L/\epsilon)$, where $L$ is an upper bound on all of the Lipschitz constants. The algorithms in the second class are accelerated versions of those in the first class, where the complexity result is improved to $O(\sqrt{(K-1)L/\epsilon})$ while the computational effort required at each iteration is almost unchanged. To the best of our knowledge, the complexity results presented in this paper are the first ones of this type that have been given for splitting and alternating direction-type methods. Moreover, all algorithms proposed in this paper are parallelizable, which makes the...
A PARAMETER STUDY OF THE DUST AND GAS TEMPERATURE IN A FIELD OF YOUNG STARS

We model the thermal effect of young stars on their surrounding environment in order to understand clustered star formation. We take radiative heating of dust, dust-gas collisional heating, cosmic-ray heating, and molecular cooling into account. Using DUSTY, a spherical continuum radiative transfer code, we model the dust temperature distribution around young stellar objects with various luminosities and surrounding gas and dust density distributions. We have created a grid of dust temperature models, based on our modeling with DUSTY, which we can use to calculate the dust temperature in a field of stars with various parameters. We then determine the gas temperature assuming energy balance. Our models can be used to make large-scale simulations of clustered star formation more realistic.
Ground vs. surface air temperature trends: Implications for borehole surface temperature reconstructions

[1] We have analyzed the relationship between surface air temperature (SAT), ground surface temperature (GST), and snow cover (SNC) over the terrestrial Northern Hemisphere based on general circulation model (GCM) simulations using GISS modelE forced with the observed SST and radiative forcing changes from 1951–1998. While SAT is the dominant influence on GST during the warm-season, it explains only half of the variance in GST during the cold-season, with SNC and pre-conditioning by prior warm-season SAT also exhibiting a sizeable and, in places, dominant influence. During a period of coincident surface warming and cold-season snowcover decrease in the model (1971–1998), mean GST increases are 0.2°C less than those in SAT, a consequence of greater exposure of the ground surface to winter cold air outbreaks. Interpretations of past SAT trends from borehole-based GST reconstructions may therefore be substantially biased by seasonal influences and snow cover changes.
Estimating the prevalence of deception in online review communities

Consumers' purchase decisions are increasingly influenced by user-generated online reviews. Accordingly, there has been growing concern about the potential for posting deceptive opinion spam---fictitious reviews that have been deliberately written to sound authentic, to deceive the reader. But while this practice has received considerable public attention and concern, relatively little is known about the actual prevalence, or rate, of deception in online review communities, and less still about the factors that influence it.We propose a generative model of deception which, in conjunction with a deception classifier, we use to explore the prevalence of deception in six popular online review communities: Expedia, Hotels.com, Orbitz, Priceline, TripAdvisor, and Yelp. We additionally propose a theoretical model of online reviews based on economic signaling theory, in which consumer reviews diminish the inherent information asymmetry between consumers and producers, by acting as a signal to a product's true, unknown quality. We find that deceptive opinion spam is a growing problem overall, but with different growth rates across communities. These rates, we argue, are driven by the different signaling costs associated with deception for each review community, e.g., posting requirements. When measures are taken to increase signaling cost, e.g., filtering reviews written by first-time reviewers, deception prevalence is effectively reduced.
Glomerular and tubular function in non-oliguric acute renal failure☆

Glomerular and tubular function were evaluated in 30 non-oliguric patients with increasing azotemia following open heart surgery. Fractional clearances (theta) of test solutes relative to that of inulin were determined. In 16 patients, theta dextran (radius 22 to 30 A) exceeded unity, a finding attributed to inulin backleak through necrotic tubules. These patients were classified as having acute renal failure; 14 subsequently required dialysis. In the remaining patients (N = 14), theta dextran was normal. These patients were considered to have prerenal failure; all recovered spontaneously. clearance of inulin (Cin) was lower in acute renal failure than in prerenal failure (12 +/- 2 versus 18 +/- 2 ml/min/1.73 m2; p less than 0.025). The apparent difference in glomerular filtration rate when Cin is used as an index was abolished, however, when Cin in acute renal failure was corrected for tubule backleak of inulin. In acute renal failure, fractional clearance of p-aminohippurate (theta PAH) was 7.1 +/- 1.0, and fractional excretion of potassium (FEk) was 160 +/- 18 percent. These findings strongly suggest that secretory ability in both proximal and terminal tubule augments, respectively, is preserved in acute renal failure. Compared with prerenal failure, the urine-to-plasma inulin ratio was lower (U/Pin = 10 +/- 1 versus 25 +/- 4; p less than 0.005) and FENa was higher (FENa = 5.1 +/- 1.5 versus 0.5 +/- 1.0 percent; p less than 0.01) in acute renal failure.
Partial breast irradiation delivered with proton beam: results of a phase II trial.

Abstract Background and Purpose A phase II trial sought to determine the safety and efficacy of proton beam irradiation to deliver partial breast radiotherapy after lumpectomy for early-stage breast cancer. Patients and Methods Eligible patients included women with invasive nonlobular carcinoma ≤ 3 cm. Surgical therapy included lumpectomy with negative margins and negative axillary lymph nodes on sampling. Postoperative proton radiotherapy to the surgical bed with an additional 1-cm margin was delivered by 40 Gy in 10 fractions over a 2-week course. Patients received systemic therapy as recommended after proton treatment. Patients had clinical evaluations every 6 months and annual mammograms. Results Fifty patients were enrolled; median follow-up was 48 months. All patients completed the prescribed treatment. Acute toxicities were limited to mild radiation dermatitis. Late skin toxicities included 3 grade 1 telangiectasias. There were no posttreatment infections or ulcerations and no cases of fat necrosis, rib fractures, radiation pneumonitis, or cardiac events. Actuarial 5-year overall survival and disease-free survival rates were 96% and 92%, respectively. No local failures occurred. Ipsilateral breast cancer developed in 1 patient 5.5 years after treatment. Dose-volume histogram analysis showed near-complete elimination of dose to the contralateral breast, lung, and heart. Conclusion Proton partial breast radiotherapy appeared to be a feasible method of treatment and provided excellent disease control within the ipsilateral breast. Treatment-related toxicity was minimal and no technical limitations prevented treatment delivery. The incidence of posttreatment complications may be less than that reported when using more invasive techniques; comparative trials should be considered.
Integrable Generalized Thirring Model

Abstract We derive the conditions that the coupling constants of the generalized Thirring model have to satisfy in order for the model to admit an infinite number of commuting classical conserved quantities. Our treatment uses the bosonized version of the model, with periodic boundary conditions imposed on the space coordinate. Some explicit examples that satisfy these conditions are discussed. We show that, with a different set of boundary conditions, there exist additional conserved quantities, and we find the Poisson bracket algebra satisfied by them.
Mass lesion detection with a fuzzy neural network

Abstract This paper presents a novel fuzzy neural network (FNN) approach to detect malignant mass lesions on mammograms. The FNN is a self-adjusting and adaptive system. It is simple in structure and easy to incorporate experts’ knowledge and fuzzified factors in the detection of malignant mass lesions on mammograms. The FNN has four layers. The first layer is the input layer consisting of 4 fuzzy neurons. The second layer has 4 ordinary neurons. The third layer consists of N maximum fuzzy neurons. The number of fuzzy neurons, N, in the third layer is determined during the training process and varies with the network parameters and data distribution. The fourth layer has 2 maximum fuzzy neurons and one competitive fuzzy neuron. Mammograms were obtained from the digital database for screening mammography, DDSM. Six-hundred and seventy regions of interest (ROIs) were extracted from 100 mammograms. All extracted ROIs were randomly divided into two sets: training and testing sets. The co-occurrence matrix of each ROI was computed. Textural features were calculated at sizes of 256×256 and 768×768, respectively. The feature differences at these two image sizes were computed for each feature. These feature differences are very discriminant in differentiating between malignant masses and normal tissues regardless of lesion shape, size, and subtlety. After training, the FNN can correctly detect all malignant masses on mammograms in the testing group. The true-positive fraction (TPF) is 0.92 when the number of false positives (FP) is 1.33 per mammogram and 1.0 when the FP is 2.15 per mammogram. The proposed approach will be very useful for breast cancer control.
Retrospect and prospect: information systems research in the last and next 25 years

To its detriment, past research in information systems (IS) has taken for granted many of its own key concepts, including ‘information,’ ‘theory,’ ‘system,’ ‘organization,’ and ‘relevance.’ This essay examines these concepts, shows how they have been neglected, and offers the prospect in which research in IS no longer models itself on the research disciplines found in the natural and social sciences, but instead charts a course for its future development by modeling itself on the research disciplines found in the professions, such as medicine, engineering, architecture, and law.
Anomalous thermalization of fast ions in magnetized plasma.

A novel anomalous process causing the perpendicular energy of fast ions to be thermalized and lost on average to bulk ion heating, instead of classical slowing down and bulk electron heating, is investigated with particle-in-cell simulations. More than half of the fast ions are slowed down to the thermal ion level, although some are heated to twice their birth energy. The fast ion density perturbation is large. This process is excited by a new two-gyro-stream instability and may continually occur in a burning plasma. The implications for fusion ignition and fast ion confinement are assessed.
Birefringence and Depolarized Light Scattering from Ordered Block Copolymers with Anisotropic Distributions of Grain Orientations Produced by Shear Flow

We have observed birefringence and depolarized light scattering patterns with 2-fold symmetry from a cylindrical diblock copolymer solution that was ordered under shear flow. We have developed a theory to account for such 2-fold symmetric scattering patterns, based on a model that assumes an anisotropic orientation distribution of ellipsoidal grains in the sample. We also show how scattering patterns can be approximately reduced to the sum of three terms of the form Cn(θ) cos(nφ), where θ and φ are polar angles in the detection plane and n = 0, 2, and 4. By comparing the experimentally determined Cn(θ) functions with theoretical calculations, we estimated the fraction of the sample that is composed of misaligned grains, their size and eccentricity, and the angular range over which their optic axes were distributed (Δϑ). The analysis of the optical properties of these kinds of systems is complicated by the fact that the signal from misaligned grains diminishes extremely rapidly as Δϑ decreases.
RANDALL–SUNDRUM AND FLIPPED SU(5)

In this paper, we construct a model based on a flipped SU(5) partial grand unified theory, within the framework of the Randall–Sundrum (RS1) proposal. Breaking of is achieved using a bulk scalar field in the 10 of SU(5), Φ, which gains a vacuum expectation value ~ 3 × 1015GeV. We are able to retain the successes of the phenomenology, specifically the confinement of all fields to the smallest (1, , and 10) representations of SU(5). We derive the beta functions, and point out some constraints on bulk matter content implied by the runnings (and positivity) of the five-dimensional coupling. Finally, we comment on baryon decay and show the fine-tuning problem required to prevent an exponentially short proton lifetime.
Researcher Perspectives on Publication and Peer Review of Data

Data “publication” seeks to appropriate the prestige of authorship in the peer-reviewed literature to reward researchers who create useful and well-documented datasets. The scholarly communication community has embraced data publication as an incentive to document and share data. But, numerous new and ongoing experiments in implementation have not yet resolved what a data publication should be, when data should be peer-reviewed, or how data peer review should work. While researchers have been surveyed extensively regarding data management and sharing, their perceptions and expectations of data publication are largely unknown. To bring this important yet neglected perspective into the conversation, we surveyed ~ 250 researchers across the sciences and social sciences– asking what expectations“data publication” raises and what features would be useful to evaluate the trustworthiness, evaluate the impact, and enhance the prestige of a data publication. We found that researcher expectations of data publication center on availability, generally through an open database or repository. Few respondents expected published data to be peer-reviewed, but peer-reviewed data enjoyed much greater trust and prestige. The importance of adequate metadata was acknowledged, in that almost all respondents expected data peer review to include evaluation of the data’s documentation. Formal citation in the reference list was affirmed by most respondents as the proper way to credit dataset creators. Citation count was viewed as the most useful measure of impact, but download count was seen as nearly as valuable. These results offer practical guidance for data publishers seeking to meet researcher expectations and enhance the value of published data.
Resolving the pulsations of subdwarf B stars: HS 0039+4302, HS 0444+0458 and an examination of the group properties of resolved pulsators

ABSTRACT We continue our program of single-site observations of pulsating subdwarf B (sdB)stars and present the results of extensive time series photometry of HS 0039+4302and HS 0444+0458. Both were observed at MDM Observatory during the fall of2005. We extend the number of known frequencies for HS 0039+4302 from 4 to14 and discover one additional frequency for HS 0444+0458, bringing the total tothree. We perform standard tests to search for multiplet structure, measure amplitudevariations, and examine the frequency density to constrain the mode degree l.Includingthe two stars in this paper,23 pulsatingsdB stars have receivedfollow-up observations designed to decipher their pulsation spectra. It is worth an examina-tion of what has been detected. We compare and contrast the frequency content interms of richness and range and the amplitudes with regards to variability and diver-sity. We use this informationto examine observationalcorrelationswith the proposedκ pulsation mechanism as well as alternative theories.Key words:Stars: oscillations–stars: variables–stars: individual (HS 0039+4302,HS 0444+0857)– Stars: subdwarfs
Four short stories about Toeplitz matrix calculations

The stories told in this paper are dealing with the solution of finite, infinite, and biinfinite Toeplitz-type systems. A crucial role plays the off-diagonal decay behavior of Toeplitz matrices and their inverses. Classical results of Gelfand et al. on commutative Banach algebras yield a general characterization of this decay behavior. We then derive estimates for the approximate solution of (bi)infinite Toeplitz systems by the finite section method, showing that the approximation rate depends only on the decay of the entries of the Toeplitz matrix and its condition number. Furthermore, we give error estimates for the solution of doubly infinite convolution systems by finite circulant systems. Finally, some quantitative results on the construction of preconditioners via circulant embedding are derived, which allow us to provide a theoretical explanation for numerical observations made by some researchers in connection with deconvolution problems.
Strain-specific spontaneous activation during mouse oocyte maturation.

Objective To examine whether spontaneous oocyte activation is determined by genetic differences and interacts with culture environment. Design Experimental study. Setting Temple University School of Medicine. Animal(s) C57BL/6, DBA/2, C3H/HeJ, and A/J strains, along with reciprocal F1 hybrid female mice (5–6 weeks). Intervention(s) Immature oocytes from different mouse strains collected and cultured in different maturation conditions, including different serum, serum replacement, bovine serum albumin (BSA), and follicle-stimulation hormone (FSH). Main Outcome Measure(s) The emission of first polar body, pronucleus formation, meiotic arrest, spontaneous activation, and expression of maturation regulators. Result(s) Oocytes from C57BL/6 mice display a high rate of delayed first meiotic division and spontaneous activation after the first meiotic division with in vitro maturation (IVM), and the second meiotic division with in vivo maturation (VVM) after superovulation. Spontaneous activation with IVM is sensitive to culture environment. Oocytes that spontaneously activated during the first meiotic division with IVM have unusual replicated sister chromatid pairs with slight connections at centromeres at first mitosis, whereas oocytes that activated in vivo display haploidization from the second meiotic division. Spontaneous activation is also seen in F1 hybrid oocytes, indicating a dominant trait from C57BL/6. Delayed meiosis was associated with reduced cyclin B and securin expression. Conclusion(s) Both mouse strain and culture environment have a statistically significant effect on the incidence of meiotic defects and spontaneous activation. Reduced expression of meiotic regulators may underlie this effect.
Almost random : evaluating a large-scale randomized nutrition program in the presence of crossover

This brief summarizes the results of a gender impact evaluation study, entitled Almost random : evaluating a large-scale randomized nutrition program in the presence of crossover, conducted in 2002 in Senegal. The study observed the impact of the nutrition enhancement program, which aims to improve child nutrition in Senegal based on a large-scale randomized community intervention on the individual level. The intervention increases weight for age by 0.1 standard deviations. Parent's education improves the nutrition status, and the results do not differ between genders. There was a reduction of giving non-breast milk liquids to infants of 11 percent in the treatment group. After controlling for observable characteristics, there is about 0.27 standard deviation increase in weight-for-age score.
Unsteady RANS simulation of turbulent flow and heat transfer in ribbed coolant passages of different aspect ratios

Abstract The flow and heat transfer in ribbed coolant passages of aspect ratios (AR) 1:1, 4:1, and 1:4 are numerically studied through the solution of the unsteady Reynolds averaged Navier–Stokes (URANS) equations. The URANS procedure, which utilizes a two equation k – e model for the turbulent stresses, is shown to resolve large-scale bulk unsteadiness. The computations are carried out for a fixed Reynolds number of 25,000 and density ratio of 0.13, while the Rotation number is varied between 0.12 and 0.50. At higher rotation numbers (⩾0.5) at least three inter-rib modules are required to ensure periodicity in the streamwise direction. The flow exhibits unsteadiness in the Coriolis-driven secondary flow and in the separated shear layer. The average duct heat transfer is the highest for the 4:1 AR case. For this case, the secondary flow structures consist of multiple roll cells that direct flow both to the trailing and leading surfaces. The 1:4 AR duct shows flow reversal along the leading surface at high rotation numbers. For this AR, the potential for conduction-limited heat transfer along the leading surface is identified. The friction factor reveals an increase with the rotation number, and shows a significant increase at higher rotation numbers (∼ Ro = 0.5).
On the Relative Rates of Decay of the Optical and Soft X-ray Fluxes in Dwarf Nova Outbursts

We present time-dependent computations utilizing the accretion disk limit cycle instability to model the decay of the flux in dwarf nova outbursts. In particular, we model the optical and 0.1 keV fluxes in an attempt to account for recent findings by Ponman et al. The e-folding decay times of ~3 days for the optical and ~1 day for the soft X-ray/EUV in an outburst of SS Cygni are naturally accounted for in the model by the action of the cooling front which enacts the transition between the high and low states in the accretion disk. The difference in timescales between V and EUV stems from the fact that, roughly speaking, the optical flux samples the surface area of the hot part of the accretion disk, whereas the EUV samples the mass of the hot part of the accretion disk.
Reduction of one-loop tensor form factors to scalar integrals: a general scheme

Abstract A general method for reducing tensor form factors, which appear in one-loop calculations in dimensional regularization, to scalar integrals is presented. The method is an extension of the reduction scheme introduced by Passarino and Veltman [Nucl. Phys. B 160 (1979) 151] and is applicable in all regions of parameter space including those where the kinematic Gram determinant vanishes. New relations between the form factors that are valid for the vanishing Gram determinant play a key role in the extended scheme.
On-the-fly decompression and rendering of multiresolution terrain

We present a streaming geometry compression codec for multiresolution, uniformly-gridded, triangular terrain patches that supports very fast decompression. Our method is based on linear prediction and residual coding for lossless compression of the full-resolution data. As simplified patches on coarser levels in the hierarchy already incur some data loss, we optionally allow further quantization for more lossy compression. The quantization levels are adaptive on a per-patch basis, while still permitting seamless, adaptive tessellations of the terrain. Our geometry compression on such a hierarchy achieves compression ratios of 3:1 to 12:1.Our scheme is not only suitable for fast decompression on the CPU, but also for parallel decoding on the GPU with peak throughput over 2 billion triangles per second. Each terrain patch is independently decompressed on the fly from a variable-rate bitstream by a GPU geometry program with no branches or conditionals. Thus we can store the geometry compressed on the GPU, reducing storage and bandwidth requirements throughout the system.In our rendering approach, only compressed bitstreams and the decoded height values in the view-dependent "cut" are explicitly stored on the GPU. Normal vectors are computed in a streaming fashion, and remaining geometry and texture coordinates, as well as mesh connectivity, are shared and re-used for all patches. We demonstrate and evaluate our algorithms on a small prototype system in which all compressed geometry fits in the GPU memory and decompression occurs on the fly every rendering frame without any cache maintenance.
The Euler characteristic of a polyhedral product

Given a finite simplicial complex L and a collection of pairs of spaces indexed by the vertices of L, one can define the “polyhedral product” of the collection with respect to L. We record a simple formula for its Euler characteristic. In special cases the formula simplifies further to one involving the h-polynomial of L.
The Nature of Government Finance in Brazil

The aim of this paper is to focus on the institutional process by which the Brazilian government spends, borrows, and collects taxes. I am going to evaluate the conventional view that taxes finance government spending, that bond sales are financing operations, and that the Brazilian federal government is operationally constrained. This view arises from a misunderstanding of both treasury and central bank operations. Balance sheets are used to show the reserve effects of the treasury and central bank operations and to explain the cooperation between the central bank and the treasury. It concludes that logically taxes and bonds can not finance government spending and that a sovereign government that issues its own non convertible currency can not become insolvent.
The CDF-II silicon tracking system☆

Abstract The CDF silicon tracking system for Run II of the Fermilab Tevatron consists of eight layers arranged in cylinders spanning radii from 1.35 to 28 cm , and lengths from 90 cm to nearly 2 m for a total of 6 m 2 of silicon and 722,000 readout channels. With an innermost layer (Layer 00) utilizing radiation tolerant p+-in-n silicon and low-mass readout cables between the sensors and readout electronics, double-sided vertexing layers (SVXII) designed for use with a deadtimeless secondary-vertex trigger, and outermost layers (Intermediate Silicon Layers) utilizing mass-producible modules attached to a carbon fiber spaceframe, this system is a starting point for the next generation of silicon trackers for the LHC and Tevatron.