cssi/SciSciGPT-SciSciNet huggingface dataset:
Population pulsations and sidemode generation in semiconductors

This paper applies many-body theory for an electron-hole plasma in semiconductors to multimode semiconductor-laser operation and sidemode generation. We derive third-order laser amplitude and frequency-determining equations and the corresponding propagation equations for multiwave mixing. The equations are similar to those found in multimode gas-laser theory. We include the effects of population pulsations in the total carrier density, but, due to the rapid carrier-carrier scattering, we explicitly suppress spectral hole burning. We also include band-gap renormalization and Coulomb enhancement contributions. The theory is evaluated numerically for the example of nondegenerate four-wave mixing in an amplifier configuration. We discuss the dependence of the sidemode intensity on the length of the active medium, the intermode beat frequency, and the pump-wave intensity.
Note: On cocircuit covers of bicircular matroids

Given a graph G, one can define a matroid M=(E,C) on the edges E of G with circuits C where C is either the cycles of G or the bicycles of G. The former is called the cycle matroid of G and the latter the bicircular matroid of G. For each bicircular matroid B(G), we find a cocircuit cover of size at most the circumference of B(G) that contains every edge at least twice. This extends the result of Neumann-Lara, Rivera-Campo and Urrutia for graphic matroids.
An Architecture for Distributed Environment Sensing with Application to Robotic Cliff Exploration

Future planetary exploration missions will use cooperative robots to explore and sample rough terrain. To succeed robots will need to cooperatively acquire and share data. Here a cooperative multi-agent sensing architecture is presented and applied to the mapping of a cliff surface. This algorithm efficiently repositions the systems' sensing agents using an information theoretic approach and fuses sensory information using physical models to yield a geometrically consistent environment map. This map is then distributed among the agents using an information based relevant data reduction scheme. Experimental results for cliff face mapping using the JPL Sample Return Rover (SRR) are presented. The method is shown to significantly improve mapping efficiency over conventional methods.
Bargaining with commitment, choice of techniques, and direct foreign investment

Abstract Once a firm has installed a plant in a host country, the country will have an incentive to reopen negotiations concerning tax rates. This paper examines the incentives for the country to commit to not reopening negotiations. A commitment deters the firm from inefficiently reducing the capital intensity of its investment but apparently surrenders tax revenues by not exploiting the country's post-entry bargaining power. We show that commitment will be optimal as long as the tax system does not place too distortionary a burden on capital and the country has access to capital markets.
Systolic hypertension: an overview

This article provides a descriptive survey of the problem of systolic hypertension. Throughout, 2 types of systolic hypertension will be described: isolated systolic hypertension, which is the most common type of elevated blood pressure in the elderly, and uncontrolled but treated hypertension, which is characterized by elevations in systolic blood pressure (SBP) that are substantially greater than elevations in diastolic blood pressure (DBP). The population variance in SBP vastly exceeds that observed in DBP. The distinction between the 2 aspects of SBP is largely semantic and based upon the somewhat arbitrary blood pressure classification schemes. In this discussion, untreated or uncontrolled hypertension refers to SBP z140 mm Hg and/or DBP z90 mm Hg, as specified in The Sixth Report of the Joint National Committee (JNC-VI) on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. We will start with a brief survey of the demographics and epidemiology of the population with systolic hypertension. We then review the epidemiologic and observational data on the risk associated with systolic hypertension. Within this section, we focus on the risk associated with pulse pressure (PP) (=SBP DBP), which has special relevance to the isolated systolic hypertension population. We will explore the results of treatment trials that address control of systolic hypertension. Finally, we address the challenges of blood pressure control concentrating on risk reduction. Physician habits are addressed in this context. With greater appreciation of the dangers of systolic hypertension, physicians may improve the quality of care they provide.
Forest composition at varying distances from a coal-burning power plant☆

Examination of the effects of sulphurous emissions from a coal-burning power plant on the vegetation of a mixed oak forest with white pine Pinus strobus L. and hemlock Tsuga canadensis (L.) Carr revealed that species diversity and importance values of certain species were inversely related to distance from the source of emission. Diversity and importance of white pine Pinus strobus L. and sweet birch Betula lenta L. increased with distance whereas the importance of white oak Quercus alba L. and red maple Acer rubrum L. decreased. Differences with distance were greater downwind than upwind. The data fitted hyperbolic equations using the reciprocal of distance from the emission source. Species richness and diversity were more sensitive indicators of pollution damage than growth assessments of individual overstorey species or groups of species.
Aggregation of evidence from random and fuzzy sets

Alternative rules for the aggregation of different sources of information are discussed in the ambit of random set theory, which gives a general framework in the field of the uncertainty measures, containing probabilistic measures, set-based models (interval analysis or more generally convex models), fuzzy sets and possibility theory as particular extreme cases. Analogies and extensions of the corresponding rules are underlined with reference both to probabilistic procedures and to fuzzy sets operations.
Instrument hardware and software upgrades at IPNS

IPNS is in the process of upgrading their time-of-flight neutron scattering instruments with improved hardware and software. The hardware upgrades include replacing old VAX Qbus and Multibus-based data acquisition systems with new systems based on VXI and VME. Hardware upgrades also include expanded detector banks and new detector electronics. Old VAX Fortran-based data acquisition and analysis software is being replaced with new software as part of the ISAW project. ISAW is written in Java for ease of development and portability, and is now used routinely for data visualization, reduction, and analysis on all upgraded instruments. ISAW provides the ability to process and visualize the data from thousands of detector pixels, each having thousands of time channels. These operations can be done interactively through a familiar graphical user interface or automatically through simple scripts. Scripts and operators provided by end users are automatically included in the ISAW menu structure, along with those distributed with ISAW, when the application is started.
Influence of dominance status on adrenal activity and ovarian cyclicity status in captive African elephants.

The North American African (Loxodonta africana) elephant population is not self-sustaining, in part because of a high rate of abnormal ovarian activity. About 12% of adult females exhibit irregular cycles and 31% do not cycle at all. Our earlier work revealed a relationship between dominance status and ovarian acyclicity, with dominant females being more likely to not cycle normally. One theory is that dominant females may be expending more energy to maintaining peace within the captive herd than for supporting reproduction. The goal of this study was to determine if there was a relationship among dominance status, serum cortisol concentrations, and ovarian acyclicity. We hypothesized that adrenal glucocorticoid activity would be increased in dominant, noncycling elephants as compared with subdominant individuals. Blood samples were collected weekly over a 2-year period in 81 females of known dominance and cyclicity status, and analyzed for cortisol. Based on a path analysis model (Reticular Action Model Or Near Approximation [RAMONA]), noncycling, dominant African elephant females did not have higher mean serum cortisol concentrations, or exhibit more variability (i.e., coefficient of variation, standard deviation) in cortisol secretion. This study suggests that alterations in adrenal activity are not related to dominance status nor contribute directly to acyclicity in captive African elephants. Zoo Biol 29:168–178, 2010. © 2009 Wiley-Liss, Inc.
Size of smallest coalition as a source of power in coalition bargaining

Six-person groups of male or female undergraduates played I2 trials of a simple coalition game that varied the sizes of the coalitions available to the players. Results indicated that the size of a player’s smallest available coalition was inversely related to the player’s outcomes. The most important outcome differences included effects of player position and interactions of position by trial block. The critical implications of these results for minimum power theory, Roth-Shapley value, weighted probability model, bargaining theory, and equal excess model are discussed, and quantitative tests of these theories are also presented. Minor gender differences were obtained, and it is suggested that future research use both male and female subjects. A description of the bargaining process, based on the subjects’ responses to a post-session questionnaire and our observations, is given.
The Molecular Biology Database Collection: an updated compilation of biological database resources

The Molecular Biology Database Collection is an online resource listing key databases of value to the biological community. This Collection is intended to bring fellow scientists' attention to high-quality databases that are available throughout the world, rather than just be a lengthy listing of all available databases. As such, this up-to-date listing is intended to serve as the initial point from which to find specialized databases that may be of use in biological research. The databases included in this Collection provide new value to the underlying data by virtue of curation, new data connections or other innovative approaches. Short, searchable summaries of each of the databases included in the Collection are available through the Nucleic Acids Research Web site, at http://www. nar.oupjournals.org.
Evaluation Practice among Community-Based Organizations: Research into the Reality.

Increasingly, government, foundations, and others are asking community-based organizations for more evaluation information. Although the demand for this information may be increasing, the field kno...
Regions of convergence of the Rayleigh quotient iteration method

The Rayleigh quotient iteration method finds an eigenvector and the corresponding eigenvalue of a symmetric matrix. This is a fundamental problem in science and engineering. Parlett and Kahan have shown, in 1968, that for almost any initial vector in the unit sphere, the Rayleigh quotient iteration method converges to some eigenvector. In this paper, the regions of the unit sphere which include all possible initial vectors converging to a specific eigenvector are studied. The generalized eigenvalue problem Ax = λBx is considered. It is shown that the regions do not change when the matrix is shifted or multiplied by a scalar. These regions are completely characterized in the three-dimensional case. It is shown that, in this case, the area of the region of convergence corresponding to the interior eigenvalue is larger than the area of those corresponding to any extreme one. This can be interpreted, with the appropriate choice of probability distribution, as: the probability of converging to an eigenvector corresponding to the interior eigenvalue is larger than the probability of converging to an eigenvector corresponding to any extreme eigenvalue. It is conjectured that the same is true for matrices of any order. Experiments in higher dimensions are presented which conform with the conjecture.
A simulation of a supercell thunderstorm with emulated radiative cooling beneath the anvil

Abstract This note reports the preliminary results of an ongoing numerical study designed to investigate what effects, if any, radiative transfer processes can have on the evolution of convective storms. A pair of idealized three-dimensional simulations are conducted to demonstrate the potential dynamical importance of shortwave radiation reductions within the large shadows cast by storms. One of the simulations (the control) is run without surface physics and radiation. In the other simulation, radiative cooling due to cloud shading is emulated by prescribing a cooling rate to the skin temperature at any grid point at which cloud water was present overhead. The imposed skin cooling rate is consistent with past observations. Low-level air temperatures are coupled to the skin cooling in this second simulation by the inclusion of surface sensible heat fluxes using simple bulk aerodynamic drag laws (latent and soil heat fluxes are not included). Significant differences are observed between the two simulated ...
A Neural Mechanism for Reward Discounting: Insights from Modeling Hippocampal–Striatal Interactions

Decision-making often requires taking into consideration immediate gains as well as delayed rewards. Studies of behavior have established that anticipated rewards are discounted according to a decreasing hyperbolic function. Although mathematical explanations for reward delay discounting have been offered, little has been proposed in terms of neural network mechanisms underlying discounting. There has been much recent interest in the potential role of the hippocampus. Here we demonstrate that a previously-established neural network model of hippocampal region CA3 contains a mechanism that could explain discounting in downstream reward-prediction systems (e.g., basal ganglia). As part of its normal function, the model forms codes for stimuli that are similar to future, predicted stimuli. This similarity provides a means for reward predictions associated with future stimuli to influence current decision-making. Simulations show that this "predictive similarity" decreases as the stimuli are separated in time, at a rate that is consistent with hyperbolic discounting.
A simple quantitative method for α-amylase determinations

Abstract An amyloclastic method of amylase measurement using iodine merely as a differential stain is described. The technique is applicable to high amylase activities (25–750 IU/ml) as encountered in saliva or in purification procedures. Normal serum amylase levels are below the threshold of this method. Thin starch-agar plates of constant composition are poured on a transparent base, small wells are filled with constant microvolumes of samples, and two concentrations (e.g., 50 and 500 IU/ml) of α-amylase standard are included with each plate. After a constant time (e.g., 2 hr) of incubation at 37°C, the plates are developed and immediately thereafter diameters of amylolytic zones are recorded to tenths of millimeters. Unknown concentrations are derived by geometric or arithmetic comparison with the reference standards on the same plate—keeping in mind the linear relation between diameters and log concentrations. Concentrations from replicate plates are averaged. The estimated coefficient of variation is 11.5%. Greater accuracy can be obtained by using the average of replicate plates.
A new method of producing 4x hybrid true potato seed

New haploid-wild species hybrids (H-S) with desirable tuber type and 2n gamete production have been identified. They provide the opportunity for the production of inexpensive, 4x hybrid TPS from 2x×2x crosses. A proposed system to utilize plants producing either 2n eggs or 2n pollen is described. One H-S hybrid (female parent) would be selected for male fertility, self-incompatibility, high frequency of 2n eggs and no 2n pollen; an unrelated H-S (male parent) for male fertility and high 2n pollen production. In addition both parents would be selected for profuse flowering, attractiveness to bumblebees and other desirable characteristics. The male and female parents would be planted in alternate hills with bumblebees doing the pollinations. The elimination of emasculation, pollen collection, and hand pollination could reduce 4x hybrid TPS costs by more than 50 percent.
Negative chronotropic effect of chronic ethanol ingestion in the rat.

Abstract The chronic consumption of ethanol has been correlated with the development of arrhythmias. This study looked at the effect of chronic ethanol ingestion on the action potential of sino-atrial cells. The studies were carried out on hearts excised from male Long-Evans hooded rats, pair-fed on ethanol (E) or control (C) liquid diet. The ethanol diet supplied 35–39% of calories as ethanol. The studies of isolated sino-atrial tissue were carried out after 18–20 weeks, 30–32 weeks and 40–42 weeks on the diet. Sino-atrial cells from E and C rats were compared for changes in spontaneous rate, action potential amplitude, time to repolarize to −70 mV, and resting membrane potential. At 18–20, 30–32 and 40–42 weeks the spontaneous rate of firing of the sinus node was significantly lower in the E group as was the maximum response to isoproterenol. The time to repolarize to −70 mV was longer in E. The endogenous level of catecholamines was also lower in the E group.
An orbiting clock experiment to determine the gravitational red shift

Orbiting clock experiment for measuring gravitational red shift of earth by comparing ground based and satellite-borne hydrogen maser clocks
Photoelasticity with finite deformations

In this paper we consider the propagation of plane electromagnetic waves in a non-absorbing material which is subjected to finite deformations. It is assumed that the material is isotropic when undeformed and when no electromagnetic fields are present and that it is centrosymmetric. The theory is formulated from both Eulerian and Lagrangian points-of-view. The latter formulation rests on the Lagrangian formulation of Maxwell’s equations for a deformed material due to Walker, Pipkin and Rivlin [1].
Boys’ Perceptions of Singing A Review of the Literature

Boys seem to progress through phases in which they like to sing in early elementary school, they think that singing is for girls and, thus, unacceptable in late elementary school, and then, gradual...
PRIMARY PRODUCTION REQUIRED TO SUPPORT BOTTLENOSE DOLPHINS IN A SALT MARSH ESTUARINE CREEK SYSTEM

We developed a model to estimate the proportion of annual primary production required to support bottlenose dolphins within the 32-km 2 North Inlet salt marsh creek system in South Carolina, U.S.A. The estimated annual prey consumption by dolphins was compared to the total annual production of prey available to dolphins, as determined from estimates of annual primary production, trophic transfer efficiencies, and the mean trophic level of prey. A best estimate range of 3.2%-6.8% of the total annual primary production of the North Inlet system was required to support an average population of only six dolphins (maximum range of 0.4%-7.0%). Dolphins were estimated to consume 11.1-14.2 metric tons of fish (wet weight) each year in North Inlet. The proportion of North Inlet primary production required to support dolphins increased dramatically during the winter months, when primary production declined but dolphin numbers remained similar. This period was marked by a decline in the abundance of available prey species and by a shift in the creek utilization patterns of dolphins. Despite the numerical scarcity of dolphins in the system, they appear to have a significant ecological impact and may be important predators of overwintering prey species.
Molecular design of multifunctional food additives: antioxidative antifungal agents.

A series of alkyl 3,4-dihydroxybenzoates (protocatechuates) was synthesized, and their fungicidal activity against Saccharomyces cerevisiae was assayed using a 2-fold serial broth dilution method. Nonyl and octyl 3,4-dihydroxybenzoate were noted to be the most effective against this yeast with the minimum fungicidal concentration of 12.5 μg/mL each. The activity was found to correlate with the hydrophobic alkyl chain length. The time−kill curve study showed that nonyl 3,4-dihydroxybenzoate was fungicidal against S. cerevisiae at any growth stage and this activity was not influenced by pH values. The fungicidal activity of alkyl 3,4-dihydroxybenzoates was noted in combination with their ability to disrupt the native membrane-associated function nonspecifically as surface-active agents (surfactants) and to inhibit the respiratory electron transport. However, the primary fungicidal activity of nonyl 3,4-dihydroxybenzoate likely comes from its ability to act as a surfactant. Keywords: Fungicidal activity; Sac...
Some recent results on discrete velocity models and ramifications for lattice Boltzmann equation

Some rigorous results on discrete velocity models are briefly reviewed and their ramifications for the lattice Boltzmann equation (LBE) are discussed. In particular, issues related to thermodynamics and H-theorem of the lattice Boltzmann equation are addressed. It is argued that for the lattice Boltzmann equation satisfying the correct hydrodynamic equations, there cannot exist an H-theorem. Nevertheless, the equilibrium distribution function of the lattice Boltzmann equation can closely approximate the genuine equilibrium which minimizes the H-function of the corresponding continuous Boltzmann equation. It is also pointed out that the “equilibrium” in the LBE models is an attractor rather than a true equilibrium in the rigorous sense of H-theorem. Since there is no H-theorem to guarantee the stability of the LBE models at the attractor, the stability of the attractor can only be studied by means other than proving an H-function.
Microchannel plate intensifier response in transverse magnetic field

Gain and image shift measurements are presented for a proximity-focussed microchannel plate (MCP) image intensifier as a function of magnetic field (to 0.12 T) transverse to the optical axis. A simple model involving the angle of electron deflection, end-spoiled channel length and effective open area is described which agrees with the experiment.
Dynamics of a nonlinear periodic structure with cyclic symmetry

The free and forced motions of a nonlinear periodic structure with cyclic symmetry are studied. The structure consists of a number of identical linear flexural members coupled by means of nonlinear stiffnesses of the third degree. It is found that this system can only possessn “similar” nonlinear modes of free oscillation, and that no other modes are possible. Moreover, there exist pairs of nonlinear modes with mutually orthogonal nodal diameters having, in general, distinct “backbone” curves. A multiple-scales averaging analysis is used to study the nonlinear interaction between a pair of modes with orthogonal nodal diameters. As a result of this analysis, it is found that all pairs of nonliner modes along with all their linear combinations are orbitally unstable, and the only possible orbitally stable periodic motions are free travelling waves, that propagate through the structure in the clockwise and anti-clockwise directions. Under harmonic forcing, a bifuraction of a stable branch of forced travelling waves from a branch of forced normal mode motions is detected, and “jump” phenomena between branches of periodic solutions are observed. The analytical results are in agreement with experimental observations of an earlier work, and, in addition, are verified by numerical simulations.
Majority of patients receiving initial therapy with lenalidomide-based regimens can be successfully mobilized with appropriate mobilization strategies.

Majority of patients receiving initial therapy with lenalidomide-based regimens can be successfully mobilized with appropriate mobilization strategies
Time of arrival in quantum and Bohmian mechanics

In a recent paper Grot, Rovelli, and Tate (GRT) [Phys. Rev. A 54, 4676 (1996)] derived an expression for the probability distribution $\ensuremath{\pi}(T;X)$ of intrinsic arrival times $T(X)$ at position $x=X$ for a quantum particle with initial wave function $\ensuremath{\psi}(x,t=0)$ freely evolving in one dimension. This was done by quantizing the classical expression for the time of arrival of a free particle at $X,$ assuming a particular choice of operator ordering, and then regulating the resulting time of arrival operator. For the special case of a minimum-uncertainty-product wave packet at $t=0$ with average wave number $〈k〉$ and variance $\ensuremath{\Delta}k$ they showed that their analytical expression for $\ensuremath{\pi}(T;X)$ agreed with the probability current density $J(x=X,t=T)$ only to terms of order $\ensuremath{\Delta}k/〈k〉.$ They dismissed the probability current density as a viable candidate for the exact arrival time distribution on the grounds that it can sometimes be negative. This fact is not a problem within Bohmian mechanics where the arrival time distribution for a particle, either free or in the presence of a potential, is rigorously given by $|J(X,T)|$ (suitably normalized) [W. R. McKinnon and C. R. Leavens, Phys. Rev. A 51, 2748 (1995); C. R. Leavens, Phys. Lett. A 178, 27 (1993); M. Daumer et al., in On Three Levels: The Mathematical Physics of Micro-, Meso-, and Macro-Approaches to Physics, edited by M. Fannes et al. (Plenum, New York, 1994); M. Daumer, in Bohmian Mechanics and Quantum Theory: An Appraisal, edited by J. T. Cushing et al. (Kluwer Academic, Dordrecht, 1996)]. The two theories are compared in this paper and a case presented for which the results could not differ more: According to GRT's theory, every particle in the ensemble reaches a point $x=X,$ where $\ensuremath{\psi}(x,t)$ and $J(x,t)$ are both zero for all $t,$ while no particle ever reaches $X$ according to the theory based on Bohmian mechanics. Some possible implications are discussed.
Segmental resection spares pulmonary function in patients with stage I lung cancer

Abstract Background Segmental resection for stage I non–small cell lung cancer remains controversial. Reports suggest that segmentectomy confers no advantage in preserving lung function and compromises survival. This study was undertaken to assess the validity of those assertions. Methods We retrospectively analyzed patients undergoing lobectomy (n = 147) or segmentectomy (n = 54) for stage I non–small cell lung cancer between March 1996 and June 2001. All patients were included in the survival analysis. Pulmonary function testing was obtained preoperatively and at 1 year and included forced vital capacity, forced expiratory volume in 1 second, maximum voluntary ventilation, diffusing capacity, and stair-stepper exercise. Patients with recurrent disease (lobectomy, n=32; segmentectomy, n=10) were excluded in the pulmonary function testing analysis to avoid the confounding variables of tumor or treatments. Results Preoperative pulmonary function tests in segmentectomy patients were significantly reduced compared with lobectomy (forced expiratory volume in 1 second, 75.1% versus 55.3%; p p = 0.406) with a 1-year survival of 95% for lobectomy and 92% for segmentectomy. Four - year survivals were 67% and 62%, respectively. Conclusions For patients with stage I non–small cell lung cancer, segmental resection offers preservation of pulmonary function compared with lobectomy and does not compromise survival. Segmentectomy should be considered whenever permitted by anatomic location.
Statistical variability: what does it mean in risk assessment?

Abstract An essential part of toxicologic research involves assessing the risk from exposure to chemicals, drugs, or other potentially harmful substances. Epidemiologic information establishes an association but not a casual relationship between risk factors and adverse health outcomes. Controlled experiments in laboratory animals, however, provide insight into the agent-outcome relationship and aid in establishing low-risk exposure levels for humans. This is especially true in studies of reproduction and development since epidemiologic data are often limited. While controlled experiments reduce certain difficulties inherent interpreting epidemiologic data, there still remains the problem of careful evaluation of statistical information. This note addresses issues in the interpretation of statistical variability in fitting dose-response models and estimating exposures associated with a low (or at least specified) level of risk.
Retrocaval routing of the right internal thoracic artery

Abstract Enhanced use of the right internal thoracic artery affords further opportunity for myocardial revascutarization using predominantly arterial conduits. High proximal dissection and routing of the right internal thoracic artery behind the superior vena cava can sometimes allow additional length to the right internal thoracic artery pedicle to facilitate the grafting of posterior and lateral coronary arteries via a less circuitous, more protected route.
Turbofan Engine Control System Design Using the LQG/LTR Methodology

Application of the Linear-Quadratic-Gaussian with Loop-Transfer-Recovery methodology to design of a control system for a simplified turbofan engine model is considered. The importance of properly scaling the plant to achieve the desired Target-Feedback-Loop is emphasized. The steps involved in the application of the methodology are discussed via an example, and evaluation results a presented for a reduced-order compensator. The effect of scaling the plant on the stability robustness evaluation of the closed-loop system is studied in detail.
Perfect matchings in random graphs with prescribed minimal degree

We consider the existence of perfect matchings in random graphs with n vertices (or n + n vertices in the bipartite case) and m random edges, subject to a lower bound on minimum vertex degree. A random bipartite graph without isolated vertices and m n edges with high probability (whp) has a perfect matching iff the average vertex degree is \( 0.5\log n + \log \log n + c_n ,c_n \to \infty \) however slow. A random graph with minimum degree at least two whp has a matching that matches all the vertices except “odd-man-out” vertices, one per each isolated cycle of odd length, and one for the remaining vertex set if its cardinality is odd. So, for n even, whp the random graph has a perfect matching if it does not have isolated odd cycles.
Grammar-based task analysis of web logs

The daily use of Internet-based services is involved with hundreds of different tasks being performed by multiple users. A single task is typically involved with a sequence of Web URLs invocation. We study the problem of pattern detection in Web logs to identify tasks performed by users, and analyze task trends over time using a grammar-based framework. Our results are demonstrated on a corporate Intranet portal application with 7000 users over a 6 week period and demonstrate compelling business value from this high-level task analysis.
Strategic Profiles and Performance: An Empirical Test of Select Key Propositions

Competing theories on internal orientation versus external orientation are examined. The relevant theories are amalgamated and condensed into a number of competing propositions that are empirically tested. The findings suggest that the internally oriented businesses as well as the externally oriented businesses underperform the efficient, marketing oriented businesses.
Revised age calibration points for the geomagnetic polarity time scale

Two of the seven Cenozoic age calibration points in the widely used Cande and Kent's geomagnetic polarity time scale have recently been revised. The rest of the five calibration points are revised here based on recently available radioisotopic dates and magnetostratigraphic data. Ages of the magnetic reversals are recalculated using the revised calibration points. Differences between the present time scale and Cande and Kent's revised time scale are generally less than 0.3 m.y., the largest (up to 1.3 m.y.) being in the early Miocene.
Effect of Digoxin on Ventricular Remodeling and Responsiveness of β-Adrenoceptors in Chronic Volume Overload:

BACKGROUND: Digoxin improves baroreflex function and reduces neurohumoral activation in severe heart failure, but it is uncertain how digoxin affects ventricular remodeling and progression to left ventricular dysfunction. In addition, the effect of digoxin in in vitro beta-adrenoceptor density and function, and contractile reserve in vivo is not well understood. METHODS AND RESULTS: To study this, we compared digoxin with placebo treatment in rats with chronic volume overload induced by aortocaval fistula and in sham-operated control animals. Left ventricular end-diastolic cavity dimensions (LVDd) and wall thickness were measured weekly by in vivo transthoracic echocardiography, and left ventricular mass (LVM) and percent fractional shortening (%FS) were calculated. Six weeks after fistula creation, simultaneous echocardiographic and invasive hemodynamic evaluation at rest and in response to incremental dobutamine (1-10 µg/kg/min intravenously) were measured. Myocardial plasma membrane beta-adrenoceptor density and maximal adenylate cyclase responses (V(max)) to isoproterenol, 5'-guanylylimi dodiphosphate, and forskolin were measured in vitro. Volume overload induced progressive increases in LVDd and LVM over the 6-week study period. Percent fractional shortening at rest, and the change in %FS in response to dobutamine stress were dramatically reduced 6 weeks after fistula creation. Although 6-week fistula animals had unchanged beta-adrenoceptor density (B(max)) and binding affinity (K(d)) as compared with controls, maximal adenylate cyclase responses to stimulation in vitro (V(max)) were markedly reduced. Digoxin treatment prevented this loss of responsiveness of adenylate cyclase but did not affect beta-adrenoceptor density or affinity in vitro. Digoxin had no effect on LVDd, LVM, %FS, or the response to dobutamine infusion in vivo. CONCLUSIONS: Although digoxin prevented beta-adrenoceptor desensitization and improved in vitro myocardial adenylate cyclase response, the cardiac response to adrenergic stimulation in vivo was not significantly improved. These results suggest that the role of beta-adrenoceptor desensitization in the progression from volume overload hypertrophy to left ventricular dysfunction and heart failure may be less important than previously thought. Furthermore, although digoxin treatment did produce modest hemodynamic benefits, it did not prevent progressive remodeling in this model.
On the Catalytic Mechanism of Choline Oxidase

Choline oxidase catalyzes the four-electron oxidation of choline to glycine betaine, with betaine aldehyde as an intermediate. In this study, primary deuterium and solvent kinetic isotope effects have been used to elucidate the mechanism for substrate oxidation by choline oxidase using both steady-state kinetics and rapid kinetics techniques. The D(kcat/Km) value with 1,2-[2H4]-choline at saturating oxygen concentration was independent of pH in the range between 6.5 and 10, with a value of approximately 10.6, indicating that CH bond cleavage is not masked by other titratable kinetic steps belonging to the reductive half-reaction. In agreement with this conclusion, a Dkred value of approximately 8.9 was determined at pH 10 for the anaerobic reduction of the flavin by choline, irrespective of whether aqueous or deuterated solvent was used. At pH 10, both the D2(O)(kcat/Km) and the D2(O)kred values were not different from unity with choline or 1,2-[2H4]-choline, while the Dkcat and D2(O)kcat values were 7.3 and 1.1, respectively. The kcat and kred values were 133 s(-1) and 135 s(-1) with betaine aldehyde and 60 s(-1) and 93 s(-1) with choline. These data are consistent with a chemical mechanism in which the choline hydroxyl proton is not in flight in the transition state for CH bond cleavage and with chemical steps of flavin reduction by choline and betaine aldehyde being rate limiting for the overall turnover of the enzyme.
Super-High-Dose Islet Transplantation Is Associated With High SUITO Index and Prolonged Insulin Independence: A Case Report

Introduction. One of the current issues of clinical islet transplantation is the difficulty to achieve a prolonged insulin-free status. Functional islet mass gradually decreased after transplantation. We developed the SUITO index, which reflects engrafted islet mass. The SUITO (Secretory Unit of Islet Transplant Objects) index more than 26.0 is associated with an insulin-free status. In this study, we have experienced that super-high-dose islet transplantation maintained insulin-free status and a high SUITO index for a prolonged period. Materials and methods. Two islet isolations were performed in February 2007 and January 2008. Ductal injections were performed at the procurement site using the ET-Kyoto solution and pancreata preserved by a two-layer method. Islets were isolated using the modified Ricordi method. Both isolated islets were transplanted into a type 1 diabetic patient. Efficacy of islet transplantation was assessed by the amount of insulin requirements and SUITO index. Results. Islet yields were 514,467 islet equivalents (IE) and 872,174 IE, with purities of 49% and 85% for the first and second islet transplantations, respectively. The patient received a total of 24,327 IE/kg body weight. The immunosuppression was based on the Edmonton protocol. After the second islet transplantation, the average SUITO index for the following 1 month was 48.5, and the patient became insulin-free. At postoperative day 1006, the SUITO index was 44.6 and the patient maintained an insulin-free status with excellent glycemic control. Conclusion. Super-high-dose islet transplantation was associated with an high SUITO index and prolonged insulin independence.
Intergenerational Exchange and Expected Support Among the Young-Old

The authors used data from the Wisconsin Longitudinal Study (N = 5,023) to determine how 3 attributes of intergenerational exchange (content, direction, and recency) are associated with older adults' expected sick care and comfort from their adult children. They found more like-kind associations (expecting same types of support that had been exchanged before) than spillover associations (expecting different types of support than that had been exchanged before). Same patterns of like-kind associations were found for expected sick care and comfort, regardless of the direction and recency of exchange, but expected sick care and comfort had different patterns of spillover associations. Specifically, recent emotional transfer, upward or downward, was related to expected sick care, but only recent upward instrumental transfer was related to expected comfort. This study advances the gerontological literature by elucidating the complex relations between each of the 3 attributes of intergenerational exchange and expected support among older adults.
Online Adaptive Estimation of Sparse Signals: Where RLS Meets the $\ell_1$ -Norm

Using the l1-norm to regularize the least-squares criterion, the batch least-absolute shrinkage and selection operator (Lasso) has well-documented merits for estimating sparse signals of interest emerging in various applications where observations adhere to parsimonious linear regression models. To cope with high complexity, increasing memory requirements, and lack of tracking capability that batch Lasso estimators face when processing observations sequentially, the present paper develops a novel time-weighted Lasso (TWL) approach. Performance analysis reveals that TWL cannot estimate consistently the desired signal support without compromising rate of convergence. This motivates the development of a time- and norm-weighted Lasso (TNWL) scheme with l1-norm weights obtained from the recursive least-squares (RLS) algorithm. The resultant algorithm consistently estimates the support of sparse signals without reducing the convergence rate. To cope with sparsity-aware recursive real-time processing, novel adaptive algorithms are also developed to enable online coordinate descent solvers of TWL and TNWL that provably converge to the true sparse signal in the time-invariant case. Simulated tests compare competing alternatives and corroborate the performance of the novel algorithms in estimating time-invariant signals, and tracking time-varying signals under sparsity constraints.
Solubilization and Characterization of a Protective Antigen of Erysipelothrix rhusiopathiae

Abstract A particulate fraction of Erysipelothrix rhusiopathiae cultures has been subjected to butanol extraction and treatment with surface-active agents in an attempt to solubilize a protective antigen. The particulate fraction was partitioned into the butanol layer but was not solubilized. Only sodium dodecyl sulfate solubilized the particles. The soluble protective activity was not sedimented by centrifugation at 198,000 × g for 12 hr but was excluded by Sephadex G-200. Immunodiffusion studies of the soluble fraction demonstrated eight antigens, five of horse serum origin and three of E. rhusiopathiae origin. Ultracentrifugation indicated that spontaneous reaggregation occurred after removal of the sodium dodecyl sulfate. Analytical ultracentrifugation showed that 90% of the sodium dodecyl sulfatetreated material migrated as a single homogeneous 3.5S component. The physical and biological characteristics of the protective activity suggest that the protective antigen is a glyco-lipoprotein.
Steady-state dynamics of Cajal body components in the Xenopus germinal vesicle

Cajal bodies (CBs) are evolutionarily conserved nuclear organelles that contain many factors involved in the transcription and processing of RNA. It has been suggested that macromolecular complexes preassemble or undergo maturation within CBs before they function elsewhere in the nucleus. Most such models of CB function predict a continuous flow of molecules between CBs and the nucleoplasm, but there are few data that directly support this view. We used fluorescence recovery after photobleaching (FRAP) on isolated Xenopus oocyte nuclei to measure the steady-state exchange rate between the nucleoplasm and CBs of three fluorescently tagged molecules: U7 small nuclear RNA, coilin, and TATA-binding protein (TBP). In the nucleoplasm, the apparent diffusion coefficients for the three molecules ranged from 0.26 to 0.40 microm2 s-1. However, in CBs, fluorescence recovery was markedly slower than in the nucleoplasm, and there were at least three kinetic components. The recovery rate within CBs was independent of bleach spot diameter and could not be attributed to high CB viscosity or density. We propose that binding to other molecules and possibly assembly into larger complexes are the rate-limiting steps for FRAP of U7, coilin, and TBP inside CBs.
Are Patched Machines Really Fixed

Updating and patching has become a ubiquitous part of software maintenance, with particular importance to security. It's especially crucial when the systems in question perform vital functions and security compromises might yield drastic consequences. Unfortunately, updates intended to remediate security problems are sometimes incomplete, are flawed, or introduce new vulnerability themselves. The authors present several examples of such instances in a widely used electronic voting system, a device for which security is critical. A central lesson of the study is that evaluating a system's security by examining changes between revisions is insufficient; you must evaluate and analyze the system as a whole.
The Effect of Political Regime on Civil War: Unpacking Anocracy

Research published in the American Political Science Review shows that anocracies—as defined by the middle of the Polity index of political regime—are more susceptible to civil war than are either ...
Proteolytic stress: A unifying concept for the etiopathogenesis of Parkinson's disease

The etiopathogenesis of Parkinson's disease (PD) has been elusive. Recently, several lines of evidence have converged to suggest that defects in the ubiquitin-proteasome system and proteolytic stress underlie nigral pathology in both familial and sporadic forms of the illness. In support of this concept, mutations in alpha-synuclein that cause the protein to misfold and resist proteasomal degradation cause familial PD. Similarly, mutations in two enzymes involved in the normal function of the ubiquitin-proteasome system, parkin and ubiquitin C-terminal hydrolase L1, are also associated with hereditary PD. Furthermore, structural and function defects in 26/20S proteasomes with accumulation and aggregation of potentially cytotoxic abnormal proteins have been identified in the substantia nigra pars compacta of patients with sporadic PD. Thus, a defect in protein handling appears to be a common factor in sporadic and the various familial forms of PD. This hypothesis may also account for the vulnerability of the substantia nigra pars compacta in PD, why the disorder is age related, and the nature of the Lewy body. It has also facilitated the development of experimental models that recapitulate the behavioral and pathological features of PD, and hopefully will lead to the development of novel neuroprotective therapies for the disorder.
Control of aromatic waste air streams by soil bioreactors

Three soils were examined for the ability to degrade hydrocarbon vapors of benzene, toluene, ethylbenzene, and o-xylene (BTEX). Each of these compounds are major aromatic constituents of gasolines. The soils examined were Rubicon Sand from Traverse City, Michigan, Durant Loam from Ada, Oklahoma, and Dougherty Sand from Stratford, Oklahoma. Soil columns were used to examine the effects of soil type, air flow rate and inlet vapor concentrations. Adjustment of the hydrocarbon loading rate produced removals which corresponded to first-order removal kinetics. Estimated residence times of 10 to 20 minutes produced removals of the individual inlet BTEX compounds which ranged from 8 to 39%. Increasing the residence time produced increased removals corresponding to first-order removal rates. Further increases in the residence time revealed transport limitations which restricted additional removals. Soil which had moisture less than 50% of saturation displayed preferential utilization of benzene followed in order by ethylbenzene, toluene, and o-xylene.
How do-not-resuscitate orders are utilized in cancer patients: Timing relative to death and communication-training implications

Objectives:End-of-life communication is crucial because most U.S. hospitals implement cardiopulmonary resuscitation (CPR) in the absence of do-not-resuscitate directives (DNRs). Despite this, there is little DNR utilization data to guide the design of communication-training programs. The objective of this study was to determine DNR utilization patterns and whether their use is increasing.Methods:A retrospective database analysis (2000–2005) of DNR data for 206,437 patients, the entire patient population at Memorial Sloan-Kettering Cancer Center (MSKCC), was performed.Results:The hospital recorded, on average, 4,167 deaths/year. In 2005, 86% of inpatient deaths had a DNR, a 3% increase since 2000 (p < .01). For patients who died outside the institution (e.g., hospice), 52% had a DNR, a 24% increase over 6 years (p < .00001). Adult inpatients signed 53% of DNRs but 34% were signed by surrogates. The median time between signing and death was 0 days, that is, the day of death. Only 5.5% of inpatient deaths had previously signed an outpatient DNR. Here, the median time between signing and death was 30 days.Significance of results:Although DNR directives are commonly utilized and their use has increased significantly over the past 6 years, most cancer patients/surrogates sign the directives on the day of death. The proximity between signing and death may be a marker of delayed end-of-life palliative care and suboptimal doctor–patient communication. These data underscore the importance of communication-training research tailored to improve end-of-life decision making.