cssi/SciSciGPT-SciSciNet huggingface dataset:
The Origin and Evolution of Halo Bias in Linear and Nonlinear Regimes

We present results from a study of bias and its evolution for galaxy-size halos in a large, high-resolution simulation of a low-density, cold dark matter model with a cosmological constant. In addition to the previous studies of the halo two-point correlation function, we consider the evolution of bias estimated using two different statistics: power spectrum bP and a direct correlation of smoothed halo and matter overdensity fields bδ. We present accurate estimates of the evolution of the matter power spectrum probed deep into the stable clustering regime [k ~ (0.1-200) h Mpc-1 at z = 0] and find that its shape and evolution can be well described, with only a minor modification, by the fitting formula of Peacock & Dodds. The halo power spectrum evolves much slower than the power spectrum of matter and has a different shape which indicates that the bias is time and scale dependent. At z = 0, the halo power spectrum is antibiased (bP < 1) with respect to the matter power spectrum at wavenumbers k ~ (0.15-30) h Mpc-1 and provides an excellent match to the power spectrum of the Automatic Plate Measuring Facility (APM) galaxies at all probed k. In particular, both the halo and matter power spectra show an inflection at k ≈ 0.15 h Mpc-1, which corresponds to the present-day scale of nonlinearity and nicely matches the inflection observed in the APM power spectrum. We complement the power spectrum analysis with a direct estimate of bias using smoothed halo and matter overdensity fields and show that the evolution observed in the simulation in linear and mildly nonlinear regimes can be well described by the analytical model of Mo & White, if the distinction between formation redshift of halos and observation epoch is introduced into the model. We present arguments and evidence that at higher overdensities the evolution of bias is significantly affected by dynamical friction and tidal stripping operating on the satellite halos in high-density regions of clusters and groups; we attribute the strong antibias observed in the halo correlation function and power spectrum to these effects. The results of this study show that despite the apparent complexity, the origin and evolution of bias can be understood in terms of the processes that drive the formation and evolution of dark matter halos. These processes conspire to produce a halo distribution quite different from the overall distribution of matter, yet remarkably similar to the observed distribution of galaxies.
Generating embedded software from hierarchical hybrid models

Benefits of high-level modeling and analysis are significantly enhanced if code can be generated automatically from a model such that the correspondence between the model and the code is precisely understood. For embedded control software, hybrid systems is an appropriate modeling paradigm because it can be used to specify continuous dynamics as well as discrete switching between modes. Establishing a formal relationship between the mathematical semantics of a hybrid model and the actual executions of the corresponding code is particularly challenging due to sampling and switching errors. In this paper, we describe an approach to compile the modeling language Charon that allows hierarchical specifications of interacting hybrid systems. We show how to exploit the semantics of Charon to generate code from a model in a modular fashion, and identify sufficient conditions on the model that guarantee the absence of switching errors in the compiled code. The approach is illustrated by compiling a model for coordinated motion of legs for walking onto Sony's AIBO robot.
Demonstration of a software design and statistical analysis methodology with application to patient outcomes data sets

Purpose: With emergence of clinical outcomes databases as tools utilized routinely within institutions, comes need for software tools to support automated statistical analysis of these large data sets and intrainstitutional exchange from independent federated databases to support data pooling. In this paper, the authors present a design approach and analysis methodology that addresses both issues. Methods: A software application was constructed to automate analysis of patient outcomes data using a wide range of statistical metrics, by combining use of C#.Net and R code. The accuracy and speed of the code was evaluated using benchmark data sets. Results: The approach provides data needed to evaluate combinations of statistical measurements for ability to identify patterns of interest in the data. Through application of the tools to a benchmark data set for dose-response threshold and to SBRT lung data sets, an algorithm was developed that uses receiver operator characteristic curves to identify a threshold value and combines use of contingency tables, Fisher exact tests, Welch t-tests, and Kolmogorov-Smirnov tests to filter the large data set to identify values demonstrating dose-response. Kullback-Leibler divergences were used to provide additional confirmation. Conclusions: The work demonstrates the viability of the design approach and the software tool for analysis of large data sets.
Isothermal vapour + liquid equilibrium measurements and correlation for the pentafluoroethane + cyclopropane and the cyclopropane + 1,1,1,2-tetrafluoroethane binary systems

Abstract Isothermal vapour + liquid equilibria data were measured for the binary systems pentafluoroethane + cyclopropane and cyclopropane + 1,1,1,2-tetrafluoroethane at 253.15, 273.15 and 293 15 K, using a static analytical method. The phase compositions at equilibrium were measured by gas chromatography. The experimental estimated accuracies are ±0.02 K for temperature, ±1 kPa for pressure, and ±0.003 in mole fraction for both liquid and vapour phase composition. Both systems show strong positive deviations from Raoult's law with the formation of an azeotrope. The experimental data were regressed using the Peng-Robinson-Stryjek-Vera equation of state, with different mixing rules, i.e. the Van der Waals mixing rule with one or two interaction parameters, and Huron-Vidal and Wong-Sandler mixing rules. A comparison with literature data was performed.
Measurement and estimation of traffic oscillation properties

The paper proposes a frequency spectrum analysis approach to improve measurements of traffic oscillation properties (e.g., periodicity, magnitude) from field data. The approach builds on standard signal processing techniques to effectively distinguish useful oscillation information from noise and nonstationary traffic trends. Compared with conventional time-domain methods, the proposed methodology systematically provides a range of information on oscillation properties. This paper also shows how to estimate oscillations experienced by drivers using detector data. Applications to real-world data from two sites show that the dominant oscillation period remains relatively invariant at each site when an oscillation propagates. Although the average oscillation periods displayed in detector data significantly vary across sites, the range of oscillations experienced by drivers are found to be more consistent.
l-O-Methylthreonine—Synthesis and mode of action as an isoleucine antagonist

Abstract l - O -Methylthreonine has been synthesized by methylation of N -carbobenzoxy- l -threonine benzyl ester and subsequent hydrogenolysis. The analog supports [ 32 P]PP i exchange catalyzed by the aminoacyl-RNA synthetases in a pH 5 fraction of Sarcoma-37 ascites cells. It does not increase the rate of exchange above that found with an optimal concentration of isoleucine, indicating that the analog is activated only by the isoleucyl-RNA synthetase. It is a potent competitive inhibitor of the rate of isoleucine- 14 C incorporation into transfer RNA. Unlike l -alloisoleucine, another competitive inhibitor of isoleucine incorporation, l - O -methylthreonine does not influence the extent of isoleucine incorporation into transfer RNA. These observations suggest that l - O -methylthreonine forms an unstable, nontransferable adenylate with the isoleucyl-RNA synthetase of the tumor cell. Similar results were obtained with aminoacyl-RNA synthetases from rat liver and rabbit reticulocytes, but not from Escherichia coli . The results help explain characteristics of the mode of action of the antimetabolite on intact cells which should prove useful in studies where a severe isoleucine deficiency is required.
Structural and mechanical characterization of ion-irradiated glassy polymeric carbon for TRISO fuel nuclear application

Tristructural isotropic (TRISO) fuel is considered as the fuel design of choice for the next generation of nuclear reactors (Generation IV). Its design consists of a fuel kernel of UO x coated with several layers having different functions. One of these functions is a containment shell/diffusion barrier for the fission fragments. Normally, the material of choice for this shell is pyrolytic carbon (PyC). The material does not offer a perfect barrier, due to its inherent crystalline structure, which is planar (like graphite) and therefore impossible to mold in one continuous sheet around the spherical fuel bead. Plane boundaries allow fragment diffusion at a much higher rate than through the plane. In this study, we investigate the possibility of replacing PyC with a different form of carbon, glassy polymeric carbon (GPC). We prepared samples of GPC and studied the evolution of their physical properties and structure as a function of the radiation environment that they were exposed to. The temperature at wh...
DNA replication and the nuclear membrane.

Abstract To investigate the relationship between the nuclear membrane and DNA replication, Chinese hamster cells were labeled with tritiated thymidine and examined by electron microscope autoradiography. Unsynchronized cells were labeled for periods ranging from 0.5 to 20 minutes. There was no relative increase in the frequency of membrane-associated grains with the shorter labeling times, indicating that the replication point is not necessarily close to the nuclear membrane. When cells were synchronized to the beginning of the S period with mitotic selection and hydroxyurea, the percentage of membrane-associated grains was very low, indicating that DNA synthesis is not initiated at the nuclear membrane. When cells synchronized by mitotic selection were labeled at various times throughout the cell cycle, the percentage of peripheral grains was low in early S period and became progressively higher toward late S period as heterochromatin began to replicate. The labeling of Unsynchronized Microtus agrestis cells indicated that much of the peripheral labeling is due to the replication of intercallary heterochromatin. The results indicate that there is no association between the nuclear membrane and DNA replication.
Finite group extensions of irrational rotations

The ergodicity of certain skew products of irrational rotations of the circle with finite groups is established with application to the construction of “well-distributed sequence generators” for finite groups.
Virtual reality for ecosystem dynamics education

This paper describes an immersive interactive virtual environment created to educate students about ecosystem dynamics. Traditional tools and methods for teaching theories regarding these dynamics use 2D static images that cannot adequately display to students the complex nature of the interactions taking place in the ecosystem, making it difficult to understand the underlying theory. An immersive interactive environment can help overcome these difficulties by allowing students to view a 3D simulation and interact with it in real-time to understand the effects of changes to the ecosystem.
Convergence and computation of describing functions using a recursive Volterra series

Presented in this paper is a comparison of algorithms for computing an approximation to the sinusoidal input describing function (SIDF) for the nonlinear differential equation ẏ(t)+b1y(t)+b2u2(t)y(t) = K(u(t)+b3u(t)) The importance of this nonlinear differential equation comes from the context of nonlinear feedback controller design. Specifically, this equation is either a linear lead or lag controller (depending on the coefficient values) augmented with a nonlinear, polynomial type term. Consequently, obtaining a SIDF representation of this nonlinear differential equation or creating a process to obtain SIDFs for other similar differential equations, will facilitate nonlinear controller design using classical loop shaping tools. The two SIDF approximations studied include the well-established harmonic balance method and a Volterra series based algorithm. In applying the Volterra series, several theoretical issues were addressed including the development of a recursive solution that calculates high order Volterra transfer functions, and the guarantee of convergence to an arbitrary accuracy. Throughout the paper, case studies are presented. Copyright © 2004 John Wiley & Sons, Ltd.
Effect of Ion Engine Exhaust on the Radiation Field of a Dipole Antenna Part I: Infinite Slab Model for the Exhaust Ion Beam

A theory of the effect of an ion rocket engine exhaust on the radiation pattern of a dipole antenna is presented. The electromagnetic equations are combined with those describing the exhaust plasma beam to calculate its equivalent effective dielectric constant. In part I of this paper, the beam is represented by an infinite slab of a homogenous plasma medium, as is usually considered in space charge neutralization studies of this type of engine. The equations of propagation of electromagnetic waves through the beam medium, are used to calculate the total dipole radiation field. The method of steepest descent is applied for the evaluation of the integrals. It is found that the dipole radiation pattern depends greatly on the beam characteristic parameters.
Erythromelalgia : Response to serotonin reuptake inhibitors

Erythromelalgia is a painful disorder of the extremities characterized by redness, swelling, a burning sensation, and an increase in skin temperature exacerbated by exposure to heat.1 An early description was reported by Mitchell 2 in 1878. He coined the term erythromelalgia to denote the clinical features of redness (erythros), involvement of the extremities (melos), and the symptom of pain (algos). Later authors suggested the name "erythermalgia" to emphasize elevated temperature of the affected extremities, 3 and others have used the term "erythralgia. ''4 There have been two recent comprehensive reviews of erythromelalgia.1, 5
Influence of protein on polysiloxane polymer formation: evidence for induction of complementary protein-polymer interactions

Results presented in the companion paper suggested that the protein itself might be actively involved in the polymerization process while being entrapped in polysiloxane polymers. It was speculated that the organo-functional side chains on the silanol monomers (or small oligomers) tended to associate with complementary residues on the protein surface during the polymerization process. This phenomenon might lead to complementary binding pockets for the protein on the polymer. To investigate this possibility, polysiloxane polymers were prepared from 3-aminopropyltriethoxysilane and tetraethylorthosilicate (1:3) in the presence of two proteins: urease and BSA. The entrapped proteins were removed by pronase digestion and washing and the resulting polymers evaluated for their ability to again bind the two proteins. It was found that urease preferentially bound to the polymer made in the presence of urease, and BSA preferentially bound to the polymer made in the presence of BSA. The absolute preferential binding excess was greater (30%) for urease binding relative to that observed for BSA (3%). However, in both cases the same relative binding ratio of 1.5 or 50% excess was found. A similar study using the closely related hemoglobin and myoglobin proteins failed to show comparable excess binding in the presence of the predetermined protein. In the latter case, it was demonstrated that the rebound proteins did not equilibrate with labeled solution proteins, indicating a very tight association with the polymer surface possibly masking any specificity which existed. However, it was possible to show that urea release of rebound hemoglobin from the polymer made in the presence of hemoglobin was less than for myoglobin bound to the same polymer and visa versa, again suggesting induced properties unique to the polymer prepared with the predetermined protein. To the extent that this notion of induced complementary order is correct, it may have implications in the development of protein specific adsorbants and in our understanding of polymer surface adhesion and the molding of template fine structure.
Ultra-rapid cycling bipolar affective disorder following a closed-head injury

A young adult with no prior history of affective disease suffered the onset of a rapid cycling bipolar illness, marginally responsive to psychotropic medications, following a mild closed-head injury, and persisting after the cognitive effects of the injury had resolved. A concurrence of findings on the neurological examination, neurobehavioural examination, SPECT scan, EEG and neuropsychological test battery suggested the presence of a diffuse cerebral injury with a predominance of left frontotemporal findings. This case demonstrates that a severe and disabling mood disorder may follow a mild head injury, and that its course may be independent of cognitive impairment and recovery.
Defect sensitivity and inspectability of the KLA SEMSpec for alternating phase-shift masks

Defect inspection and repair have been the most challenging aspect for manufacturing implementation and fabrication of alternating phase-shift technology. Optical inspection tools have difficulty detecting quartz defects because no substantial transmission difference exists between the quartz substrate and the phase-shifted regions. The presence of the phase transition regions also adds problems for optical tools by creating false defects, decreased sensitivity, or additional data sets. The following report explores the sensitivity of the KLA SEMSpec to several defect types, and sizes. The non-optical SEMSpec demonstrates some advantage over optical tools when detecting quartz, or phase defects. In contrast, the SEMSpec fails to match optical tools when considering chrome, or opaque defects. Several inspectability issues such as copper defects, and tri-tones also arise for each inspection technique which hampers manufacturability.
Foraging patterns of two syngnathid fishes: importance of harpacticoid copepods

The diets of juvenile (<g0 mm) Syngnathus scovelli and of H~ppocampus zosterae, abundant members of a resident fish community in a Thalassia testudnum seagrass bed in Tampa Bay, Florida, were examined from Apnl to October 1984. Harpacticoid copepods comprised most of the diet, both in terms of percent number and percent biomass, for the smaller size classes of S. scovelli and for H. zosterae, and harpacticoids generally had the highest index of relative importance (IRI) for both syngnathids. S. scovelli displayed ontogenetic switching to larger food items, such as amphipods. shrimp and crustacean eggs. Harpacticus sp. 1 was the most common harpacticoid copepod species found in the guts of the 2 syngnathids, but was only rarely encountered in prey samples from seagrass blades. Three other harpacticoids, Paradactylopodia brevicornis sp., Dactylopodia tisboides and Harpacticus sp. 2 had high IRIS in H. zosterae but not in S. scovelli. Vanderploeg & Scavia's selectivity index (E') was calculated for sampling dates when both species of syngnathids were most abundant, using prey density on seagrass blades as a measure of prey avadabhty. Only the harpacticoid Harpacticus sp. 1 had high positive selectivity values. MARINE ECOLOGY PROGRESS SERIES Mar. Ecol. Prog. Ser.
Scaling up Prioritized Grammar Enumeration for scientific discovery in the cloud

Symbolic Regression (SR) is the data driven search for mathematical relations as performed by a computer. In essence, SR is a search over all possible equations to find those which best model the data on hand. Prioritized Grammar Enumeration (PGE) is a recently proposed algorithm which has been shown to have great efficacy and efficiency on the Symbolic Regression problem, using just a single compute core. PGE reformulates the SR problem as a search over a grammar, makes reductions in the magnitude of the search space, and introduces mechanisms for exploring that space efficiently. Notably, PGE provides reliability and reproducibility of results, a key aspect to any system used by scientists at large. In this paper, we enhance the PGE algorithm in several ways. First, we extend PGE to discover differential equations. Second, we incorporate multiple prioritization heaps into PGE, reducing point evaluations while maintaining efficacy. Finally, we decouple the PGE subroutines into a set of services, contain each with Docker, and deploy them onto the cloud. Our algorithm experiments cover a range of dynamical systems from a multitude of domains. and our cloud experiments explore a variety of architectural setups. Our results show PGE to have great promise and efficacy in automating the discovery of equations at the scales needed by tomorrow's scientific data problems.
The effect of experimentally induced atherosclerosis on the oral structures of the rabbit

Abstract Atherosclerosis of the oral arterial vasculature was produced in rabbits by confining young animals to a cholesterol-supplemented hyperlipaemic diet for 2–6 months. Large collections of subendothelial lipid-filled foam cells were found in arteries and arterioles supplying the lips, tongue, periodontium, oral mucosa and salivary glands. Although many vessels were almost completely occluded by the atheromatous lesions, there was no gross, roentgenographic or microscopic evidence of ischaemic changes in any of the oral structures examined. Inclusion of sodium fluoride or d -catechin in the drinking water did not alter the atherogenicity of the experimental diet.
Reactions of Propylene Oxide on Supported Silver Catalysts: Insights into Pathways Limiting Epoxidation Selectivity

The reactions of propylene oxide (PO) on silver catalysts were studied to understand the network of parallel and sequential reactions that may limit the selectivity of propylene epoxidation by these catalysts. The products of the anaerobic reaction of PO on Ag/α-Al2O3 were propanal, acetone and allyl alcohol for PO conversions below 2–3%. As the conversion of PO was increased either by increasing the temperature or the contact time, acrolein was formed at the expense of propanal, indicating that acrolein is a secondary reaction product in PO decomposition. With addition of oxygen to the feedstream the conversion of PO increased moderately. In contrast to the experiments in absence of oxygen, CO2 was a significant product while the selectivity to propanal decreased as soon as oxygen was introduced in the system. Allyl alcohol disappeared completely from the product stream in the presence of oxygen, reacting to form acrolein and CO2. The product distribution may be explained by a network of reactions involving two types of oxametallacycles formed by ring opening of PO: one with the oxygen bonded to C1 (OMC1, linear) and the other with oxygen bonded to C2 (OMC2, branched). OMC1 reacts to form PO, propanal, and allyl alcohol. OMC2 can give rise to acetone and PO. (DFT) calculations have verified accessibility to the two oxametallacycle structures from propylene and PO, and have provided energy barriers for each of the steps involved in PO isomerization. This work illustrates the complex manifold of sequential reactions that contribute to the difficulty of achieving high selectivity in direct propylene epoxidation with silver catalysts.
Identifying People with Acute HIV Infection: Demographic Features, Risk Factors, and Use of Health Care among Individuals with AHI in North Carolina

Identifying and counseling individuals with Acute HIV Infection (AHI) offers a critical opportunity to avert preventable HIV transmission, however, opportunities to recognize these individuals may be missed. We surveyed 32 adults diagnosed with AHI during voluntary HIV testing from 1/1/03 to 2/28/05 in publicly funded testing sites in NC to describe their clinical, social, and behavioral characteristics. Eighty-one percent of participants were men; 59% were African American. Seventy-five percent experienced symptoms consistent with acute retroviral syndrome; although 83% sought medical care for these symptoms, only 15% were appropriately diagnosed at that initial medical visit, suggesting opportunities to diagnose these individuals earlier were missed. Eighty-five percent of the men engaged in sex with men. More than 50% of the participants thought they were infected with HIV by a steady partner. This study yields important information to assist in identifying populations at risk for or infected with AHI and designing both primary and secondary prevention interventions.
Synthesis of (2R,3R)-erythro- and (2R,3S)-threo-fluoromalate using malic dehydrogenase; stereoselectivity of malic dehydrogenase.

3-Fluorooxalacetate is a substrate for malic dehydrogenase. When enzymatic reduction is slower than the rate of epimerization of the two enantiomers, only (2R,3R)-erythro-fluoromalate is formed. Conversely, when a high enzyme level and excess of NADH lead to reduction that is fast relative to the epimerization rate, equal amounts of (2R,3R)-erythro- and (2R,3S)-threo-fluoromalate are formed. These data suggest that the V/K value for reduction of the R enantiomer to give the erythro isomer is ∼100 times greater than for reduction of the S enantiomer to give the threo isomer. The equilibrium constant for the oxidation of fluoromalate is an order of magnitude less favorable than for oxidation of malate, while the equilibrium deuterium isotope effect from deuteration at C-2 of the substrate is 1.09 for fluoromalate versus 1.18 for malate. These effects reflect the inductive effect of fluorine at the 3-position.
Hard X-Ray Production in a Failed Filament Eruption

We revisit the "failed" filament eruption of 2002 May 27, first studied in detail by Ji et al. We investigate the temporal and spatial relationship between the filament dynamics and the production of hard X-ray emission using spatially resolved high-cadence data from TRACE and RHESSI. We confirm the presence of a hard X-ray source in the corona above the filament prior to the main activation phase and identify a second coronal hard X-ray source, not considered by earlier studies, that occurs under the apex of the filament during the erupting phase when the filament is clearly strongly kinked. We argue that this second source of coronal hard X-ray emission implies ongoing magnetic reconnection in a current sheet formed via a kink instability resulting from the interaction of the two adjacent legs underneath the writhing filament, in agreement with simulation results. The presence of this second energy release site has important implications for models of solar eruptions.
Observer states and traits and the imitative process: A test of a new formulation

Abstract In three studies the formulation was tested that characteristics of the observer have an effect on imitation only in situations which provide little information concerning appropriate or expected behaviors. In Experiment I, female college students of high, medium, and low need for social approval underwent either a high or low arousal manipulation. Subjects observed a videotaped model who engaged in a size judgment task. For half the subjects the model received verbal reward (high information); for the other half the model received no feedback (low information). Subsequently, the model and subject responded alternately in the task during which no feedback was given. Neither need for social approval nor manipulated arousal was found to be systematically related to imitation in either information condition. However, the hypothesized relationships were found when subjects' arousal or anxiety levels were determined by self ratings. These results were replicated in a second, similar experiment. In a third experiment, which involved an improved arousal manipulation, the hypothesized relationships were confirmed.
Seleno Compounds and Glutathione Peroxidase Catalyzed Decomposition ofS-Nitrosothiols

Seleno compounds such as selenocystamine and seleno-D, L-cystine were found to catalyze the decomposition ofS-nitrosothiols (e.g.S-nitroso-glutathione andS-nitroso-N-acetyl-D, L-penicillamine) in the presence of different thiols (e.g. glutathione,N-acetyl-D-penicillamine and 2-mercaptoethanol), and liberate nitric oxide. It was also found that glutathione peroxidase itself can catalyze the decomposition ofS-nitroso-glutathione without the presence of any thiol or H2O2.
Evaluating forecasts of political conflict dynamics

Abstract There is considerable interest today in the forecasting of conflict dynamics. Commonly, the root mean square error and other point metrics are used to evaluate the forecasts from such models. However, conflict processes are non-linear, so these point metrics often do not produce adequate evaluations of the calibration and sharpness of the forecast models. Forecast density evaluation improves the model evaluation. We review tools for density evaluation, including continuous rank probability scores, verification rank histograms, and sharpness plots. The usefulness of these tools for evaluating conflict forecasting models is explained. We illustrate this, first, in a comparison of several time series models’ forecasts of simulated data from a Markov-switching process, and second, in a comparison of several models’ abilities to forecast conflict dynamics in the Cross Straits. These applications show the pitfalls of relying on point metrics alone for evaluating the quality of conflict forecasting models. As in other fields, it is more useful to employ a suite of tools. A non-linear vector autoregressive model emerges as the model which is best able to forecast conflict dynamics between China and Taiwan.
Serum ribonuclease levels in patients with cystic fibrosis.

Abstract The levels of serum pancreatic-type ribonuclease (RNase) activity in normal individuals and in individuals homozygous and heterozygous for the cystic fibrosis (CF) gene have been studied. In 21 CF patients, ages 3–24 years, RNase levels of 459 ± 95 units/ml did not differ significantly from the RNase levels of 467 ± 105 units/ml in 17 normal individuals of the same age group nor from those of 490 ± 52 units/ml in 5 individuals heterozygous for the CF gene.
Pattern formation in the Gray-Scott model

Abstract We investigate an elliptic system that arises in cubic autocatalytic reactions known as the Gray–Scott model. Complicated patterns were reported by Pearson in a numerical study of this system. We produce the bifurcation analysis to support the existing numerical evidence for patterns. Specifically bifurcation results and C 2 bounds for nonuniform steady states are derived.
Diet alters male horn allometry in the beetle Onthophagus acuminatus (Coleoptera: Scarabaeidae)

Darwin considered the horns of male beetles to be among the most striking examples of sexual selection. As with antlers in deer or elk, beetle horns scale positively with male body size, with the result that large males have disproportionately longer horns than small males. It is generally assumed that such scaling relationships ('static allometries') are insensitive to short-term changes in the environment, and for this reason they are regularly used as diagnostic attributes of populations or species. Here I report breeding experiments on horned beetles that demonstrate that the scaling relationship between male horn length and body size changes when larval nutrition changes. Males reared on a low-quality diet had longer horn lengths at any given body size than sibling males reared on a high-quality diet. Such 'allometry plasticity' may explain seasonal changes observed in this same scaling relationship in a natural population. These experiments demonstrate that scaling relationships of sexually selected traits can respond facultatively to variation in the environment, thereby revealing a new mechanism by which males regulate the production of exaggerated secondary sexual traits.
ISOLATION OF HEXOKINASE FROM BAKER'S YEAST.

1. A method is described for the isolation of hexokinase from baker's yeast. The method is based mainly on fractionation with alcohol and results See PDF for Structure in a 30-fold increase in specific activity. The final product could be crystallized from ammonium sulfate without change in specific activity. 2. The enzyme catalyzes a transfer of phosphate from adenosinetriphosphate to glucose, fructose, or mannose, the relative rates with these three sugars being 1:1.4:0.3. 3. With glucose as substrate, the turnover number for the crystalline enzyme is 13,000 moles of substrate per 105 gm. of protein per minute at 30° and pH 7.5. The temperature coefficient (Q10°) between 0 and 30° is 1.9. 4. Magnesium ions are necessary for the activity, the dissociation constant for the Mg++ -protein complex being 2.6 x 10–3. Fluoride in concentrations as high as 0.125 M has no inhibitory effect on the enzyme when the Mg++ and orthophosphate concentrations are 6.5 x 10–3 M and 1 x 10–3 M, respectively. 5. The crystalline enzyme shows a loss in activity when highly diluted. This loss in activity can be prevented by diluting in the presence of small amounts of other proteins. Of the various protective proteins tested, insulin was the most effective, providing complete protection in a concentration of 6 micrograms per cc.; with serum albumin, a concentration of 60 micrograms per cc. was necessary. Thiol compounds (cysteine, glutathione) exerted no protective action. 6. The inactivation of the crystalline enzyme on incubation with trypsin can be prevented to a marked degree by the presence of glucose. The instability of crude preparations of yeast hexokinase may be attributed to the presence of proteolytic enzymes, since glucose or fructose has a remarkable protective effect on such preparations.
All-optical transistor action with bistable switching in a photonic crystal cross-waveguide geometry

We demonstrate all-optical switching action in a nonlinear photonic crystal cross-waveguide geometry with instantaneous Kerr nonlinearity, in which the transmission of a signal can be reversibly switched on and off by a control input. Our geometry accomplishes both spatial and spectral separation between the signal and the control in the nonlinear regime. The device occupies a small footprint of a few micrometers squared and requires only a few milliwatts of power at a 10-Gbit/s switching rate by use of Kerr nonlinearity in AlGaAs below half the electronic bandgap. We also show that the switching dynamics, as revealed by both coupled-mode theory and finite-difference time domain simulations, exhibits collective behavior that can be exploited to generate high-contrast logic levels and all-optical memory.
Formation and cleavage of the silicon-silicon bond in disilane

Abstract Disilane was obtained in a 35 per cent yield from the reaction between potassium silyl and bromosilane in 1–2 dimethoxyethane. The yield was found to be dependent on the residence time of disilane in the reaction system. Lithium halide catalysed condensation reactions of disilane were observed and the relation between these reactions and the silyl-bromosilane reaction are discussed.
Diurnal variation of heat intake in ovariectomized, steroid-treated rats

Abstract Ovariectomized rats trained to work for radiant heat reward in a cold environment were implanted with subcutaneous Silastic capsules containing either estradiol, progesterone, both estradiol and progesterone, or no hormone. The hormone treatments produced an average plasma estradiol concentration of 41 pg/ml and progesterone concentration of 20–50 ng/ml. All groups obtained more heat behaviorally when tested during the light phase of the LD cycle than when tested in the dark. Body temperatures and metabolic rates were higher during the night than during the day. There were no differences between groups in behavioral heat intake or body temperature. All hormone-treated groups showed a greater reduction in core temperature than the control group when an exogenous source of heat was not available, but there was no substantial effect of the hormone treatments on metabolic rate except for a 6–7% increase in metabolism of the estrogen group. The increased cooling rate of all hormone-treated groups may indicate a nonspecific steroid-induced increase in heat loss in the cold. The diurnal variation in heat intake establishes the LD cycle as a significant variable in thermoregulatory behavior of the rat. Thus, behavioral heat intake is high during the day when metabolism and body temperature are low, and low at night when metabolism and body temperature are high in this nocturnal species.
Herpesviral-bacterial Coinfection in Periapical Pathosis

Two members of the herpesvirus family, human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV), seem to be important putative pathogens of human periodontitis and symptomatic periapical lesions, causing pathosis either by inducing immunosuppression with a subsequent risk of aggressive bacterial infections or by infecting of periodontal cells directly. This study aimed to relate periapical occurrence of HCMV, EBV, and herpes simplex virus active infections to clinical characteristics of periapical lesions and periapical bacterial flora. Microbial samples were collected from 34 periapical lesions in conjunction with periapical surgery. Part of the periapical specimen was frozen for virologic examination, and another part was transferred to anaerobic transport medium for bacteriologic examination. RNA was isolated by means of a guanidinium isothiocyanate-acid phenol procedure, and cDNA was produced using herpesvirus-specific primers and reverse-transcription polymerase chain reaction amplification. Bacteriologic examination was performed according to established anaerobic culture methods. Of the 34 periapical lesions studied, 20 showed both HCMV and EBV, seven showed only HCMV, one showed only EBV, and six showed neither HCMV nor EBV. Herpes simplex virus was detected in two lesions. Higher occurrence of herpesvirus was detected in large versus small periapical lesions (p < 0.001) and in symptomatic versus asymptomatic periapical lesions (p < 0.001). A total of 18 microbial groups and an average of 2.1 to 3.0 bacterial groups were isolated from various categories of periapical lesions. The important finding of this study was that most teeth with necrotic pulp and periapical lesions harbored herpesviruses in periapical granulomatous tissue. Herpesvirus species in cooperation with endodontopathic bacteria may play major roles in the etiopathogenesis of aggressive types of periapical pathosis in humans.
Viscoelastic Properties of Extruded Cereal Melts

Abstract Hydrophilic biopolymer systems reach a state of maximum plasticization at a concentration of water designated as W g ′. The thermomechanical behaviour of various extruded cereals were investigated at concentrations above and below W g ′ to determine the significance of W g ′ on the viscoelastic properties in the rubbery region above T g . Cereal melts were produced via extrusion cooking using a twin-screw extruder at in-barrel moisture contents ranging from 25 to 42% (wb). Dynamic mechanical thermal analysis (DMTA) was used to determine the viscoelastic properties for melts obtained from degermed corn meal, oat flour, pregelatinized corn starch and pregelatinized waxy maize. All of the extruded melts displayed reductions in the storage modulus of about two orders of magnitude from the glassy to rubbery regimes. At temperatures greater than 320K, another transition is apparent for extruded oat flour. These losses may be attributed to a reduction in physical crosslinks and/or entanglements. With respect to the other melts investigated, differences in the oat flour melts at temperatures above T g may be due to the increased presence of protein and lipid. Given the apparent partly crystalline nature of these melts at moisture contents g ′, the most appropriate representation of the viscoelastic properties may be isotimic plots of the viscoelastic functions. These contour plots provide a more comprehensive guide to material behaviour than the ‘traditional’ state diagrams found throughout the literature. An important point is that prediction of viscoelastic properties above T g for polymers where the internal structure changes with temperature or moisture content, cannot be predicted using the same methods of reduced variables as for amorphous polymers. Thus rather than using these methods, experimental data, such as given here, may prove to be necessary to design or understand processes involving cereal melts based on their viscoelastic properties.
Available potential energy in the northern hemisphere during the FGGE year

Northern Hemispheric twice daily data from the First GARP Global Experiment (FGGE) year are used to compare available potential energy estimates obtained using the so-called exact (isentropic) form of the equations with two commonly used approximate (isobaric) forms. The two approximate forms, one using a fixed lapse rate and the other a lapse rate which varies in the vertical, overestimate the total available potential energy except in mid-summer. The greatest difference between the exact and approximate forms is in the eddy term, which is considerably smaller in the approximate forms, especially in spring and summer. Partitioning the eddy term into its standing and transient components shows that in the exact form the standing component exceeds the transient term. This is in contrast to the approximate form in which the transient term is the larger in every month except July. The latitudinal and monthly variations of the standing and transient terms show different patterns, especially in the standing component. In the approximate form the latitude of maximum standing eddy values is near 60° N in winter but shifts equatorward to about 30° N and decreases in summer. While the exact form shows a weak winter maximum near 60° N, the dominant maximum develops near 20° N in spring and shifts poleward to about 30° N and increases in summer. The hemispheric distribution of the vertically integrated grid point values from which the eddy available potential energy was calculated and the standard deviation of these twice daily values produce results which show that the exact form values better conform to the pattern of cyclone activity than the approximate form. In general, the results indicate that the exact form of the available potential energy equations should be more extensively used in diagnostic work. DOI: 10.1111/j.2153-3490.1982.tb01841.x
Noradrenergic Inhibition of TNF Upregulation in Hemorrhagic Shock

The early stress responses to hemorrhagic shock, trauma and endotoxicosis are associated with an early proinflammatory response characterized by increased gene expression of proinflammatory cytokines,
Supranigral injection of neuregulin1-β induces striatal dopamine overflow

Previous studies have provided anatomical evidence that the functional neuregulin receptor, ErbB4, is present within the ventral midbrain where it is co-localized to dopamine neurons of the substantia nigra and ventral tegmental area. In this study, we provide evidence that neuregulin1-β (a.k.a. heregulin1-β), a neuregulin-1 gene isoform that preferentially binds to and activates the ErbB4 receptor, evokes an almost immediate overflow of striatal dopamine when injected into a region just dorsal to the ipsilateral substantia nigra. These data are indicative that neuregulins can modulate the activity of mesostriatal dopaminergic neurons.
The significance of incision and fluvial sedimentation in the Basal White River Group (Eocene-Oligocene), Badlands of South Dakota, U.S.A.

Abstract A newly defined lithostratigraphic unit, the Chamberlain Pass Formation (CPF), records the initial episode of incision, fluvial sedimentation, and pedogenesis in SW South Dakota following the retreat of the Cretaceous Interior Seaway. The CPF is Middle(?) to Late Eocene in age, and consists of fluvial sandstone and mudstone. Pedogenic modification of the unit has created a distinctive pedostratigraphic unit, the Interior Paleosol Series. The CPF thickens from west to east, achieving a maximum channel-belt thickness of ⩾ 11 m. Paleoflow data indicate that deposition of the CPF was restricted to a fault-controlled basin southeast of the Black Hills uplift. Sandstones in the CPF were derived from a recycled sedimentary rock source area to the west. In contrast, sandstones in the overlying Chadron Formation (Late Eocene) had a variety of sources including the Precambrian core rocks of the Black Hills uplift. Deposition of the CPF brackets four significant Paleogene changes in baselevel that occurred in this region. These events were: (1) Late Cretaceous to Middle(?) Eocene relative baselevel fall, weathering and erosion of the Cretaceous Pierre Shale to form the Yellow Mounds Paleosol, and fluvial incision; (2) Middle(?) to Late Eocene relative baselevel rise and deposition of the CPF; (3) Late Eocene relative baselevel fall, weathering and erosion of the CPF to form the Interior Paleosol, and fluvial incision; and (4) Late Eocene to Oligocene relative baselevel rise and deposition of the Chadron Formation. The first event was probably eustatic, the second was controlled primarily by local subsidence in a fault-bounded basin, the third records the tectonic uplift and unroofing of the Black Hills, and the fourth event was probably primarily controlled by eustasy, but other factors may have been important.
Statewide Assessment of Hospital-Based Stroke Prevention and Treatment Services in North Carolina Changes Over the Last 5 Years

Background and Purpose— The first published statewide assessment of stroke prevention and treatment services in the United States was carried out in North Carolina in 1998. The purpose of the present study was to measure changes in these services that may have occurred over the last 5 years. Methods— A 1-page questionnaire was sent to each facility in the state in February 2003. Results were compared with the 1998 survey. Results— Complete responses were obtained from each of the state’s 128 facilities. The proportions of hospitals providing CT angiography (35% versus 55%, P≤0.01), diffusion-weighted MRI (20% versus 45%, P≤0.01), transesophageal echocardiography (45% versus 59%, P≤0.02), and inpatient rehabilitation services (25% versus 43%, P≤0.01) increased over the 5 years. There was a trend toward more facilities having tissue plasminogen activator protocols (43% versus 54%, P≤0.09) but a decrease in the proportion of hospitals with interventional radiologists (23% versus 15%, P<0.01). There was no ch...
Moreau-Yosida Regularization for Grouped Tree Structure Learning

We consider the tree structured group Lasso where the structure over the features can be represented as a tree with leaf nodes as features and internal nodes as clusters of the features. The structured regularization with a pre-defined tree structure is based on a group-Lasso penalty, where one group is defined for each node in the tree. Such a regularization can help uncover the structured sparsity, which is desirable for applications with some meaningful tree structures on the features. However, the tree structured group Lasso is challenging to solve due to the complex regularization. In this paper, we develop an efficient algorithm for the tree structured group Lasso. One of the key steps in the proposed algorithm is to solve the Moreau-Yosida regularization associated with the grouped tree structure. The main technical contributions of this paper include (1) we show that the associated Moreau-Yosida regularization admits an analytical solution, and (2) we develop an efficient algorithm for determining the effective interval for the regularization parameter. Our experimental results on the AR and JAFFE face data sets demonstrate the efficiency and effectiveness of the proposed algorithm.