cssi/SciSciGPT-SciSciNet huggingface dataset:
Impaired glucose signaling as a cause of obesity and the metabolic syndrome: The glucoadipostatic hypothesis

Since nutrition-sensitive feedback signals normally act to maintain relatively stable levels of both available and stored nutritional resources, failure in one or more of these feedback signals could plausibly lead to obese phenotypes. The glucostatic hypothesis in its original form posited that glucose serves as a physiological satiety factor (in the sense that post-prandial increases in plasma glucose cause meal termination), but in this form the hypothesis has been difficult to prove, and, especially since the discovery of leptin, the glucostatic hypothesis has largely been abandoned. Nevertheless, reduction of plasma glucose levels or glucose signaling produces a profile of neuroendocrine responses similar to those produced by leptin deficiency. Since leptin is not a physiological satiety factor (because it does not increase before meal termination), yet leptin deficiency causes obesity, we suggest that the glucostatic hypothesis be re-formulated without reference to satiety (i.e., short-term effects on food intake). Instead we argue that like leptin signaling, glucose signaling regulates long-term energy balance, in part by regulating metabolic rate but also by chronically regulating food intake. We further speculate that high-fat diets produce obesity in part because carbohydrates are, per calorie, more effective than lipids to reduce food intake and increase metabolic rate. In support of this glucoadipostatic hypothesis, the present review examines evidence that obesity and the metabolic syndrome may be due to reduction in neuroendocrine sensitivity to glucose leading to increased metabolic efficiency.
Studies on Cultivation Kinetics for Elastase Production by Bacillus sp. EL31410

It was the first time to study elastase batch cultivation kinetics. This paper discusses the growth kinetics, elastase production, and substrate consumption kinetics model of Bacillus sp. EL31410 in batch cultivation. A simple model was proposed using a logistic equation for growth, the Luedeking-Piret equation for elastase production, and the Luedeking-Piret-like equation for glucose consumption. The model appeared to provide a reasonable description for each parameter during the growth phase. This study could provide some support for studying elastase fermentation kinetics, especially for studying its singular growth phenomenon. However, the model for elastase production is not good for explaining the real process and is still up to research.
Two fast approximate wavelet algorithms for image processing, classification, and recognition

We use large libraries of template waveforms with remarkable orthogonality properties to recast the relatively complex principal orthogonal decomposition (POD) into an optimization problem with a fast solution algorithm. Then it becomes practical to use POD to solve two related problems: recognizing or classifying images, and inverting a complicated map from a low-dimensional configuration space to a highdimensional measurement space. In the case where the number N of pixels or measurements is more than 1000 or so, the classical O(N3) POD algorithm becomes very costly, but it can be replaced with an approximate best-basis method that has complexity O(N2 logN). A variation of POD can also be used to compute an approximate Jacobian for the complicated map.
Gastrointestinal involvement in polyarteritis nodosa (1986–2000):: Presentation and outcomes in 24 patients

Abstract Purpose Gastrointestinal involvement in polyarteritis nodosa carries a poor prognosis. A 1982 review from our institution reported acute abdominal syndromes in 31% of patients with polyarteritis nodosa, and that all 5 patients with acute surgical abdomens died. We reviewed our more recent experience to determine if outcomes have changed since. Subjects and methods We reviewed the records of all patients with polyarteritis nodosa in our vasculitis database between 1986 and 2000. Inclusion criteria were a diagnosis of polyarteritis nodosa, symptoms or signs of gastrointestinal involvement, and either a mesenteric angiogram consistent with polyarteritis nodosa or histopathologic proof of a medium-vessel vasculitis. We calculated a prognostic (5 factor) score for all patients. Results We identified 24 patients with polyarteritis nodosa who had gastrointestinal involvement during their illness. Thirteen (54%) of the patients developed acute surgical abdomens, 3 of whom died ( P = 0.02 by comparison with the historical cohort). Mean (± SD) prognostic scores were higher among patients in the acute abdomen group compared with those who did not have acute abdominal syndromes (1.7 ± 0.9 vs. 0.6 ± 0.7, P = 0.002), corresponding with the observed mortality in these groups. Conclusion Gastrointestinal involvement occurs commonly in polyarteritis nodosa and carries a poor prognosis. Compared with a historical cohort at our institution, mortality from this complication may have decreased, perhaps because of earlier diagnosis.
Natural products as sources for new mechanisms of herbicidal action

Abstract New mechanisms of action for herbicides are highly desirable to fight evolution of resistance in weeds, to create or exploit unique market niches, and to cope with new regulatory legislation. Comparison of the known molecular target sites of synthetic herbicides and natural phytotoxins reveals that there is little redundancy. Comparatively little effort has been expended on determination of the sites of action of phytotoxins from natural sources, suggesting that intensive study of these molecules will reveal many more novel mechanisms of action. Examples of natural products that inhibit unexploited steps in the amino acid, nucleic acid, and other biosynthetic pathways are given. AAL-toxin, hydantocidin, and various plant-derived terpenoids are discussed. Strategies and potential pitfalls of using natural products as leads for new herbicide classes are summarized.
A Functional Screen Provides Evidence for a Conserved, Regulatory, Juxtamembrane Phosphorylation Site in Guanylyl Cyclase A and B

Kinase homology domain (KHD) phosphorylation is required for activation of guanylyl cyclase (GC)-A and -B. Phosphopeptide mapping identified multiple phosphorylation sites in GC-A and GC-B, but these approaches have difficulty identifying sites in poorly detected peptides. Here, a functional screen was conducted to identify novel sites. Conserved serines or threonines in the KHDs of phosphorylated receptor GCs were mutated to alanine and tested for reduced hormone to detergent activity ratios. Mutation of Ser-489 in GC-B to alanine but not glutamate reduced the activity ratio to 60% of wild type (WT) levels. Similar results were observed with Ser-473, the homologous site in GC-A. Receptors containing glutamates for previously identified phosphorylation sites (GC-A-6E and GC-B-6E) were activated to ∼20% of WT levels but the additional glutamate substitution for S473 or S489 increased activity to near WT levels. Substrate-velocity assays indicated that GC-B-WT-S489E and GC-B-6E-S489E had lower Km values and that WT-GC-B-S489A, GC-B-6E and GC-B-6E-S489A had higher Km values than WT-GC-B. Homologous desensitization was enhanced when GC-A contained the S473E substitution, and GC-B-6E-S489E was resistant to inhibition by a calcium elevating treatment or protein kinase C activation – processes that dephosphorylate GC-B. Mass spectrometric detection of a synthetic phospho-Ser-473 containing peptide was 200–1300-fold less sensitive than other phosphorylated peptides and neither mass spectrometric nor 32PO4 co-migration studies detected phospho-Ser-473 or phospho-Ser-489 in cells. We conclude that Ser-473 and Ser-489 are Km-regulating phosphorylation sites that are difficult to detect using current methods.
Establishing a Clientele: Cases of Acceptance and Denial for Pensions in Old Age

Drawing on statistics from the archives of the Luella Hannan Memorial Home, including the number of applications filed between 1927 and 1933, the gender, race, marital status and educational backgrounds of the applicants, the number of cases denied and accepted, and the reasons for these decisions, the authors characterize the “Hannan-type” as one who met the discursive, cultural, and organizational expectations of the sponsoring institution.
On robust and optimal imperfect information state equipartitioning for network systems

Abstract This paper addresses some fundamental questions towards robust and optimal imperfect information state equipartitioning by means of a computational framework of a system-theoretic approach called semistable Gaussian Linear-Quadratic Consensus (LQC), which is motivated by Optimal Semistable Control (OSC). OSC deals with an optimal regulation problem for dynamical systems with unknown, nonzero set-points. In this paper, we address stochastic OSC for robust and optimal information state equipartitioning under Gaussian white noise disturbance or measurement and random distribution of initial conditions. We develop a new framework for semistable Gaussian LQC and recast the proposed problem into an alternative, constrained optimization problem. To this end, necessary and sufficient conditions to connect semistability and optimal information state equipartitioning are derived in the paper and the existence of optimal solutions to this optimization problem has been proved for network systems. To efficiently solve the proposed constrained optimization problem, we propose a convergence guaranteed numerical algorithm. The rigorous convergence proof of this algorithm is presented and simulation results show the efficacy of the proposed approach.
Reflex Diode Experiments on Gamble II

Summary form only given. Previous experiments on the NRL Gamble II generator (2 Omega, 2 MV, 100 ns) demonstrated reflexing of MeV electrons through thin tantalum foil anodes whose thickness (13 mum) was a small fraction of the electron range (CSDA range of 1 MeV electrons in tantalum is 460 mum). The total bremsstrahlung was comparable to that from thick foils, indicating that the electrons passed (reflexed) many times through the thin foil. The reduced attenuation of low-energy (10-100 keV) photons in the thin tantalum resulted in an increased surface dose of a factor of four compared with the surface dose from the spectrum produced from thick foils. Renewed interest in this technique led to the present series of reflex diode experiments on Gamble II, where two new approaches are under investigation to enhance reflex diode capabilities. Plasma-filled reflex diodes, similar to those fielded on the Saturn generator, demonstrate the ability to operate at very low impedance and radius, potentially producing low-endpoint bremsstrahlung from high-current reflexing configurations with intensities impossible with vacuum diodes. Pulsed heating prior to and during the generator pulse is investigated as a way to degas the tantalum, delay ion formation and increase the number of passes electrons make through the tantalum, allowing thinner tantalum to be used efficiently for enhanced emission of low-energy X-rays. Results of these experiments and computer simulations will be presented
On the prediction of extreme ecological events

Ecological studies often focus on average effects of environmental factors, but ecological dynamics may depend as much upon environmental extremes. Ecology would therefore benefit from the ability to predict the frequency and severity of extreme environmental events. Some extreme events (e.g., earthquakes) are simple events: either they happen or they don't, and they are generally difficult to predict. In contrast, extreme ecological events are often compound events, resulting from the chance coincidence of run-of-the-mill factors. Here we present an environmental bootstrap method for resampling short-term environmental data (rolling the environmental dice) to calculate an ensemble of hypothetical time series that embodies how the physical environment could potentially play out differently. We use this ensemble in conjunction with mechanistic models of physiological processes to analyze the biological consequences of environmental extremes. Our resampling method provides details of these consequences that would be difficult to obtain otherwise, and our methodology can be applied to a wide variety of ecological systems. Here, we apply this approach to calculate return times for extreme hydrodynamic and thermal events on intertidal rocky shores. Our results demonstrate that the co-occurrence of normal events can indeed lead to environmental extremes, and that these extremes can cause disturbance. For example, the limpet Lottia gigantea and the mussel Mytilus californianus are co-dominant competitors for space on wave-swept rocky shores, but their response to extreme environmental events differ. Limpet mortality can vary drastically through time. Average yearly maximum body temperature of L. gigantea on horizontal surfaces is low, sufficient to kill fewer than 5% of individuals, but on rare occasions environmental factors align by chance to induce temperatures sufficient to kill >99% of limpets. In contrast, mussels do not exhibit large temporal variation in the physical disturbance caused by breaking waves, and this difference in the pattern of disturbance may have ecological consequences for these competing species. The effect of environmental extremes is under added scrutiny as the frequency of extreme events increases in response to anthropogenically forced climate change. Our method can be used to discriminate between chance events and those caused by long-term shifts in climate.
Morphological and molecular systematic study of Chondracanthus (Gigartinaceae, Rhodophyta) from Pacific North America

Abstract Species boundaries in the Gigartinaceae are poorly defined due to the high degree of phenotypic plasticity exhibited by the thallus, with the result that many superfluous taxa have been described. To clarify the taxonomy of species of Chondracanthus Kutzing reported from the Gulf of California and Pacific coast of North America, morphological and molecular phylogenetic studies were performed. Phylogenetic analyses of chloroplast and nuclear DNA yielded nearly congruent hypotheses. DNA from type material was examined from select species to validate the correspondence between modern and historically important collections. Monographic observations on species from Pacific North America were included to clarify species boundaries. Analyses identified two species from the Gulf of California and nine from the Pacific coast. The following statements are supported: (1) Gigartina serrata Gardner is independent of Chondracanthus canaliculatus (Harvey) Guiry, and Chondracanthus serratus (Gardner) comb. nov. ...
Sequential Geometric Programming for 2 × 2 Interference Channel Power Control

We analyze the performance of sequential geometric programming (SGP) in solving the nonconvex power control problem of maximizing the sum capacity of the interference channel with no multiuser decoding. We focus on the 2x2 interference channel, for which we know the optimal power allocation tuples. We validate the SGP approaches of single and double condensation methods and we analyze the accuracy and convergence performance of each.
Novel antagonist implicates the CB1 cannabinoid receptor in the hypotensive action of anandamide

In anaesthetised rats, the endogenous cannabinoid anandamide has potent cardiovascular effects that include a brief pressor effect and a more prolonged depressor response. The depressor response is attenuated after transection of the cervical spinal cord or blockade of alpha-adrenergic receptors by phentolamine, and is dose-dependently inhibited by a selective antagonist of the CB1 cannabinoid receptor. The pressor component is not affected by any of these interventions. This suggests that the depressor response is due to inhibition of sympathetic tone mediated by CB1 receptors, whereas the pressor component is due to a peripheral action that does not involve the same receptors or the sympathetic nervous system.
Superconducting Properties of Tin, Indium, and Mercury below 1° K

The superconducting critical field curves for pure Sn, In, and Hg have been measured down to about 0.3\ifmmode^\circ\else\textdegree\fi{}K. In the low-temperature region where the superconducting electronic entropy is negligible, the entropy difference (and hence the normal electronic entropy) is linear in temperature, as expected for a free electron gas. The measurements provide a sensitive test for details of the BCS theory in that the accuracy obtainable is much higher than in other experiments. A simple scaling of the energy-gap-to-temperature ratio brings the theoretical predictions into good agreement with experiment. The results are critically analyzed in the light of a possible lattice contribution to the entropy change at the superconducting transition of In, but no evidence for such a lattice contribution is found.
Gender heterogeneity, entrepreneurial orientation and international diversification

Purpose – Although diversifying internationally appears to be beneficial, relatively few small and medium‐sized firms actually participate. Building on recent research exploring the international diversification of small and medium‐sized enterprises (SMEs) the purpose of this paper is to examine the relation among ownership and management team gender heterogeneity, entrepreneurial orientation, and firm international diversity.Design/methodology/approach – The authors' hypotheses were tested using data gathered from members of Women Impacting Public Policy (WIPP), a national (US) public policy organization that advocates for women in business.Findings – Results indicate that top management team gender composition and entrepreneurial orientation are significantly related to international diversification but that ownership gender composition is not. The authors found that team entrepreneurial orientation may be useful when teams are more homogeneous on relations‐oriented characteristics such as gender.Origin...
Reason and remedy for conflicting reports on comparative effects of steel scalpel and electrosurgical cutting on gingival tissues and alveolar bone

The fact that electrosurgical cutting is governed by factors that have no influence on steel scalpel cutting is responsible for discrepancies among the results of investigations of the modalities. The investigator's equal expertise in the use of both modalities is a prerequisite for accurate comparative investigations of the effects of electrosurgical and steel scalpel cutting. Eleven specific factors that govern the efficacy and quality of electrosurgical cutting and that can, therefore, ensure consistently reliable histologic results and accurate conclusions have been mentioned.
Robbing Peter to Pay Paul: Coverage of State and International Information in Government Documents Courses

Abstract The authors surveyed instructors of graduate-level government documents courses in the United States regarding their coverage of IGO, foreign, and state government information. Though instructors value this information, most allot too few class hours to it. The creation of specialized distance education courses by an alliance of LIS programs would fill this gap.
Colorimetric determination of phenylephrine (neo‐synephrine) in pharmaceutical products

Phenylephrine may be converted to a highly colored compound by coupling with diazotized p-nitroaniline. Photometric determination of the color at 495 mμ constitutes a convenient assay method for the drug in pharmaceutical preparations.
Treatment of acute rheumatic carditis with choline magnesium trisalicylate in a patient needing surgery.

Acute rheumatic fever is a post-infectious illness characterized by diffuse inflammation. Typically, high-dose anti-inflammatory agents are used as primary therapy for this disorder. In addition to their anti-inflammatory properties, these agents, most frequently aspirin, also have anti-platelet properties. We describe the case of an 11-year-old patient with rheumatic fever who needed to undergo surgery. The use of traditional anti-inflammatory agents would have posed a potential problem with post-surgical bleeding, so a lesser-used anti-inflammatory agent (i.e., choline magnesium trisalicylate) was selected.
Rapid rotation of flagellar bundles in swimming bacteria

A bacterial flagellum is driven by a reversible rotary motor1–3. The power input is determined by protonmotive force and proton flux, the power output by torque and speed: interrelationships between these parameters provide important clues to motor mechanisms. Here we describe the relationship between torque and speed at constant protonmotive force. The measurements are analogous to those that could be made by plugging an electric motor into a constant-voltage outlet, varying the external load, and determining the torque delivered at different speeds. We used suspensions of metabolizing cells of a motile Streptococcus, varied the external load by changing the viscosity of the medium, determined motor speed from the frequency of vibration of the cell body, and inferred motor torque from the rate of body rotation. The flagellar bundles rotate more rapidly than formerly supposed, at rates that increase linearly with temperature. The torque delivered by the flagellar motor drops linearly with speed. At high speed, the torque-generating cycle associated with the transfer of one proton appears to dissipate free energy in a series of small steps.
Differential and coordinated expression of defensins and cytokines by gingival epithelial cells and dendritic cells in response to oral bacteria

Epithelial cells and dendritic cells (DCs) both initiate and contribute to innate immune responses to bacteria. However, much less is known about the coordinated regulation of innate immune responses between GECs and immune cells, particularly DCs in the oral cavity. The present study was conducted to investigate whether their responses are coordinated and are bacteria-specific in the oral cavity. The β-defensin antimicrobial peptides hBD1, hBD2 and hBD3 were expressed by immature DCs as well as gingival epithelial cells (GECs). HBD1, hBD2 and hBD3 are upregulated in DCs while hBD2 and hBD3 are upregulated in GECs in response to bacterial stimulation. Responses of both cell types were bacteria-specific, as demonstrated by distinctive profiles of hBDs mRNA expression and secreted cytokines and chemokines in response to cell wall preparations of various bacteria of different pathogenicity: Fusobacterium nucleatum, Actinomyces naeslundii and Porphyromonas gingivalis. The regulation of expression of hBD2, IL-8, CXCL2/GROβ and CCL-20/MIP3α by GECs was greatly enhanced by conditioned medium from bacterially activated DCs. This enhancement was primarily mediated via IL-1β, since induction was largely attenuated by IL-1 receptor antagonist. In addition, the defensins influence DCs by eliciting differential cytokine and chemokine secretion. HBD2 significantly induced IL-6, while hBD3 induced MCP-1 to approximately the same extent as LPS, suggesting a unique role in immune responses. The results suggest that cytokines, chemokines and β-defensins are involved in interaction of these two cell types, and the responses are bacteria-specific. Differential and coordinated regulation between GECs and DCs may be important in regulation of innate immune homeostasis and response to pathogens in the oral cavity.
Carbon Dioxide Laser Cutting of a Carbon‐Fiber–Silicon Carbide‐Matrix Composite

CO2 laser scribing and cutting were studied on a carbon-fiber-silicon carbide-matrix (C/SiO) composite nominally containing 45 vol% of carbon fibers. The scribing and cutting were performed in continuous-wave (CW) mode using laser powers between 750 and 1500 W, and specimen translation velocities between 0.5 and 4 cm/s. The laser spot size was 300 μm in diameter. The groove width and depth were measured as functions of power and velocity. The results were compared to theoretically predicted values obtained by solving the quasi-steady-state heat conduction equation in three dimensions for a moving body. Reasonably good agreement between theory and experiment was found. The microstructures of the laser-cut surfaces indicated the formation of redeposit by condensation from the vapor phase. X-ray diffraction and Raman spectroscopy analyses of the redeposit showed the presence of β-SiC and graphitic carbon. The four-point bending strength of the laser-cut composite was found to be approximately 20% lower than the corresponding strength of the diamond-cut composite. The strength was fully recovered after removing 180 ± 10 μm of the material from the lased surface by grinding. The oxidation resistance of the laser-cut and diamond-cut composites was studied with a thermogravimetric balance at 1103°, 1304°, and 1402°C in air. The oxidation behavior at all investigated temperatures for both materials was dominated by a rapid initial mass loss due to the oxidation of carbon and a possible active oxidation of SiC, followed by a slow mass gain due to the passive oxidation of SiC. At 1304°C the rate of passive oxidation of SiC in the laser-cut material was somewhat higher than in the diamond-cut material. At 1402°C, the diamond-cut surface oxidized more rapidly than the taser-cut surface. The differences in oxidation rates were attributed to the differences in microstructure.
Microfluidic add-on for standard electrophysiology chambers.

We have developed a microfluidic brain slice device (μBSD) that marries an off-the shelf brain slice perfusion chamber with an array of microfluidic channels set into the bottom surface of the chamber substrate. As this device is created through rapid prototyping, once optimized, it is trivial to replicate and share the devices with other investigators. The device integrates seamlessly into standard physiology and imaging chambers and it is immediately available to the whole slice physiology community. With this technology we can address the flow of neurochemicals and any other soluble factors to precise locations in the brain slice with the temporal profile we choose. Dopamine (DA) was chosen as a model neurotransmitter and we have quantified delivery in brain tissue using cyclic voltammetry (CV) and fluorescence imaging.
Cardiac rehabilitation after heart transplantation in a patient with Becker's muscular dystrophy: a case report.

Abstract Srinivasan R, Hornyak JE, Badenhop DT, Koch LG. Cardiac rehabilitation after heart transplantation in a patient with Becker's muscular dystrophy: a case report. Becker's muscular dystrophy (BMD) is associated with abnormal cardiac findings in 75% of cases; up to one third will develop ventricular dilatation leading to congestive heart failure, at times necessitating cardiac transplant. Candidates are selected from a base of heart failure patients who are usually New York Heart Association (NYHA) class III or IV. Treatment in a phase II cardiac rehabilitation program after transplantation is associated with functional improvement in patients without BMD, but there are no reports of patients with this disorder. We present the case of a 38-year-old man diagnosed with BMD with associated dilated cardiomyopathy. The patient was a NYHA class IIIa and underwent orthotopic cardiac transplantation for intractable heart failure followed by treatment in a phase II cardiac rehabilitation program. At the end of cardiac rehabilitation, his 12-minute walking distance had improved from 716.28 to 929.64m (30% improvement), he had increased his conditioning metabolic equivalent level from 3.5 to 5.5 (55% improvement), he had a weight loss from 81.65 to 78.93kg, and his body mass index changed from 23 to 22kg/m2. The patient now has returned to work, is using a stationary bicycle once a day for 30 minutes, and is walking 1 hour a day. This suggests that treatment in a cardiac rehabilitation program is effective in patients with BMD after cardiac transplant.
Observations of fire ants (Solenopsis invicta Buren) attacking apple snails (Pomacea paludosa Say) exposed during dry down conditions

Apple snails (Pomacea paludosa Say) in Florida wetlands and lakes must contend with water level fluctuations that periodically result in dry downs.1 In recent years we have conducted field and laboratory studies to investigate the impacts of such drying events on snail populations. Our research has focused mainly on direct mortality due to desiccation. However, during one laboratory study we identified a potential threat to snail populations from the red imported fire ant, Solenopsis invicta Buren. Since their introduction to Alabama around 1940, S. invicta has expanded its range to include all of Florida.2 S. invicta in Florida prefer disturbed sites in areas with a relatively high water table.3 The highly fragmented wetland systems of Florida provide the moisture levels and disturbance profile (periodic dry downs, as well as disturbed substrata along canals and levees) favored by S. invicta. Fire ants can be found along levees adjacent to parcels of the Everglades and Upper St. Johns River marsh, on tree islands, and along the margins of central Florida lakes (Darby, pers. obs.). Fire ant colonies were reported in up to 20% of alligator nests in central Florida lakes.4 During periods of inundation S. invicta emerge from their mounds and form floating balls, thus prolonging colony survival and aiding dispersal.5 Their adaptations to seasonal flooding and their highly successful invasion of Florida may reflect the evolution of S. invicta in South American ecosystems subjected to regular flooding.6 S. invicta are predators observed killing numerous invertebrate2,6,7 and vertebrate species4,8 and have been associated with biodiversity declines in the southeastern fauna.9 The distribution of S. invicta encompasses the entire range of the Florida apple snail. Given the critical position of the apple snail in the food web of Central and South Florida wetlands,10 vulnerability to S. invicta is of concern. We observed S. invicta attacking apple snails while conducting experiments on snail survival during dry down conditions. Ten tanks (120 cm 3 61 cm 3 46 cm), each with a sand substratum, were set up in a grassy area outside the Florida Caribbean Science Center (USGS-Biological Research Division, Gainesville, FL) in June 1998. S. invicta mounds were present in the grassy area around the tanks. These were treated throughout the experiment with a granular bait formulation of the insecticide hydramethylnon (AMDRO®). [S. invicta identification was verified at the USDA Red Imported Fire Ant Laboratory, Gainesville, FL]. Each tank contained 18–20 adult apple snails with mean (6SD) shell widths of 33.5 mm (63.5 mm). Four tanks were used as controls and kept filled with water, while the other six were Moll. Stud. (1999), 65, 507–510 © The Malacological Society of London 1999
Efficient High-Rate Secret Key Extraction in Wireless Sensor Networks Using Collaboration

Secret key establishment is a fundamental requirement for private communication between two entities. In this article, we propose and evaluate a new approach for secret key extraction where multiple sensors collaborate in exchanging probe packets and collecting channel measurements. Essentially, measurements from multiple channels have a substantially higher differential entropy compared to the measurements from a single channel, thereby resulting in more randomness in the information source for key extraction, and this in turn produces stronger secret keys. We also explore the fundamental trade-off between the quadratic increase in the number of measurements of the channels due to multiple nodes per group versus a linear reduction in the sampling rate and a linear increase in the time gap between bidirectional measurements. To experimentally evaluate collaborative secret key extraction in wireless sensor networks, we first build a simple yet flexible testbed with multiple TelosB sensor nodes. Next, we perform large-scale experiments with different configurations of collaboration. Our experiments show that in comparison to the 1 × 1 configuration, collaboration among sensor nodes significantly increases the secret bit extraction per second, per probe, as well as per millijoule of transmission energy. In addition, we show that the collaborating nodes can improve the performance further when they exploit both space and frequency diversities.
The saving–investment correlation and origins of productivity shocks

Abstract This paper shows how savings and investment can be positively correlated despite capital being perfectly mobile across countries. The saving–investment (SI) correlation depends on the origin and the volatility of macroeconomic (productivity) shocks, the persistence of these shocks and country-size. Simulating a two-country Real Business Cycle (RBC) model we show that as the variance of common shocks increases (relative to country-specific shocks), as the persistence of these shocks decreases and as country-size increases, the SI correlation increases. Using annual data from 1960 to 2002, productivity changes in 11 OECD countries are decomposed into common and country-specific shocks (from which foreign shocks are also constructed). The empirical findings show that the 11 countries share a statistically significant common component in productivity changes and common shocks generally account for at least half of the variations in the countries’ productivity changes. We then use the estimated variances of the shocks, in addition to each country's size, in the RBC model to compute the predicted SI correlation for each country, under the assumption that capital is perfectly mobile. The predicted SI correlation is then compared to the actual correlation to assess the relative degree of capital mobility in the 11 countries. The findings indicate that Norway, the Netherlands and the US have the highest degree of capital mobility whereas in Canada, Sweden, Belgium and Japan capital mobility has been the lowest.
Effects of pocket gopher burrowing on archaeological deposits: A simulation approach

The construction of burrows and movement of sediment by pocket gophers alter archaeological deposits by causing vertical size-sorting of artifacts, destruction of fragile artifacts, disruption of sedimentary structures, and organic enrichment of the subsurface. To evaluate the long-term effects of exposure to burrowing, a simulation was developed based on quantitative information on pocket gopher burrows and rates of sediment movement. Simulation results indicate the development of a distinct stone zone composed predominantly of particles greater than 6 cm after 4000–5000 years, and a logarithmic pattern to the rate of strata disruption. The patterns produced by the simulation compare well with patterns exhibited by actual archaeological deposits belonging to California's Milling Stone Horizon. These results suggest that current notions concerning the Milling Stone Horizon and other aspects of California prehistory may require revision, and that more emphasis must be placed on formation process research in such settings.
A submillimeter resolution fluorescence molecular imaging system for small animal imaging.

Most current imagingsystems developed for tomographic investigations of intact tissues using diffuse photons suffer from a limited number of sources and detectors. In this paper we describe the construction and evaluation of a large dataset, low noise tomographic system for fluorescenceimaging in small animals. The system consists of a parallel plate-imaging chamber and a lens coupled CCD camera, which enables conventional planar imaging as well as fluorescencetomography. The planar imaging data are used to guide the acquisition of a Fluorescence Molecular Tomography (FMT) dataset containing more than 10 6 measurements, and to superimpose anatomical features with tomographic results for improved visual representation. Experimental measurements exhibited good agreement with the diffusion theory models used to predict light propagation within the chamber. Tests of the instrument’s capacity to quantitatively reconstruct fluorochrome distributions in three dimensions showed less than 5% errors between actual fluorochrome concentrations and FMT findings, and suggested a detection threshold of approximately 100 femptomoles for small localized objects. Experiments to assess the instrument’s spatial resolution demonstrated the ability of the system to resolve objects placed at clear distances of less than 1 mm. This is a significant resolution increase over previously developed systems for animal imaging, and is primarily due to the large dataset employed and the use of inversion methods. Finally, the in vivoimaging capacity is showcased. It is expected that the large dataset collected can enable superior imaging of molecular probes in vivo and improve quantification of fluorescence signatures.
The durability of acoustically tested SP-11-type mullite-corundum stoppers

An investigation carried out at the Novolipetsk Metallurgical Plant of the performance of the SP-11-type mullite-corundum stoppers produced by the Semiluk Refractories Plant showed that the durability was highest in the case of stoppers with a resonance frequency of 10,000–12,000 Hz. The stoppers falling into that frequency range account for about 70% of the total output. Culling out the stoppers with resonance frequencies below 10,000 and above 12,000 Hz and the “deaf” stoppers by acoustic testing increases the performance reliability of the stoppers of pony ladles and lengthens their useful life by 0.25 melt.
Letter by Augoustides Regarding Article, “Increased Mortality, Postoperative Morbidity, and Cost After Red Blood Cell Transfusion in Patients Having Cardiac Surgery”

To the Editor: I read with great interest the excellent article by Dr Murphy and colleagues detailing the deleterious effects associated with red blood cell transfusion in cardiac surgery.1 Their multivariate analysis has demonstrated that red cell transfusion is significantly associated with increased mortality, …
Mechanism of increased cerebrospinal fluid pressure with thoracic aortic occlusion.

Abstract Recent clinical reports have suggested that drainage of cerebrospinal fluid lowers the incidence of perioperative paraplegia in patients with thoracoabdominal aneurysms. Unfortunately, the precise mechanisms for both the neurologic deficits and the beneficial effects of cerebrospinal fluid drainage remain unclear. To better understand the relationship between cerebrospinal fluid pressure, central venous pressure, and the compliance of the cerebrospinal fluid compartment, we studied 12 anesthetized dogs subjected to thoracic aortic occlusion. Pericardia were opened in six (group I), and left intact in six (group II). Systemic hemodynamics and cerebrospinal fluid pressure (mm Hg) were measured before and after thoracic aortic occlusion. In group II, intravenous volume loading (15 ml/kg) was superimposed on aortic occlusion. Compliance of the cerebrospinal fluid space (ml/mm Hg) was measured at each interval by use of sequential injection and withdrawal of small aliquots of fluid. Results are expressed as mean ± SE; * p * , group II 82.5 ± 6.9 to 98.3 ± 9.5 * ) and central venous pressure (1.9 ± 0.7 to 3.8 ± 0.6 * , 3.0 ± 0.8 to 4.0 ± 0.9 * ). Although cerebrospinal fluid pressure was increased by thoracic aortic occlusion in both groups (8.0 ± 1.2 to 12.6 ± 1.9 * ; 5.8 ± 0.9 to 8.5 ± 1.1 * ), compliance of the dural space was not changed (0.61 ± 0.19 to 0.60 ± 0.18; 0.54 ± 0.14 to 0.62 ± 0.09). In group II animals cerebrospinal fluid pressure was further increased with volume loading (8.0 ± 1.5 to 13.3 ± 1.5 * ) and changes in cerebrospinal fluid pressure and central venous pressure were correlated ( r = 0.54). The increase in cerebrospinal fluid pressure with volume loading and thoracic aortic occlusion was significantly greater than the increase in cerebrospinal fluid pressure and thoracic aortic occlusion alone (5.3 ± 0.4 vs 2.8 ± 0.6 * ). Increased cerebrospinal fluid pressure with thoracic aortic occlusion is due to volume changes in venous capacitance beds within the dural space. This change in pressure is not associated with any decrease in compliance; hence, there is no rationale for direct compression of the cord (spinal cord compartment syndrome). Based on anatomic considerations, it appears that any benefits of cerebrospinal fluid drainage reflect enhanced patency of thin-walled intradural veins, which are prone to collapse (Starling resistor concept). Further definition of the complex relationship between central and local venous volumes and pressures may allow a unified explanation for immediate and delayed neurologic deficits. (J VASC SURG 1990;11:695-701.)
Sleep in traumatic brain injury

More than one-half million patients are hospitalized annually for traumatic brain injury (TBI). One-quarter demonstrate sleep-disordered breathing, up to 50% experience insomnia, and half have hypersomnia. Sleep disturbances after TBI may result from injury to sleep-regulating brain tissue, nonspecific neurohormonal responses to systemic injury, ICU environmental interference, and medication side effects. A diagnosis of sleep disturbances requires a high index of suspicion and appropriate testing. Treatment starts with a focus on making the ICU environment conducive to normal sleep. Treating sleep-disordered breathing likely has outcome benefits in TBI. The use of sleep promoting sedative-hypnotics and anxiolytics should be judicious.
Does a Lennard-Jones glass exist?

Even at large undercoolings the viscosity of a one-component Lennard-Jones fluid may be not high enough to form a glass which would be stable on a laboratory time scale. Results of molecular dynamics simulations support this view.
Identification of certain physical parameters in hyperbolic boundary value problems from overspecified boundary data

Abstract A number of different problems for identifying unknown parameters or functions in second order hyperbolic problems from overspecifled boundary data are examined. The unknown parameters of interest include boundary parameters in a boundary condition and sources (or sinks) as well as coefficients in the differential equation itself. Explicit solutions for various problems are obtained and the existence of a solution for various others is discussed. Finally, the results of some numerical experiments are presented in order to illustrate the potential for use of the methods and ideas utilized in this report.
Beamformer enhancement by post-processing for improved spatial resolution and signal-to-noise ratio

Various methods are used in ultrasound beamforming to increase signal-to-noise ratio (SNR) and improve spatial resolution. SNR is typically improved by exploiting coherence in the RF channel data, for example summing channel data after applying focal delays in the delay-and-sum (DAS) beamformer, and summing channel data after applying a per-channel matched filter for the spatial matched filter beamformer[1]. Inverse filter methods are capable of improving spatial resolution at the cost of SNR [2],[3], or can trade resolution for SNR using a regularization parameter, but in general are very computationally intensive due to the large RF data sets used. We propose a post-processing method operating on post-summed but pre-envelope detected beamformed image data that can improve the pixel SNR and spatial resolution of any beamformer with low computational cost. This is achieved by forming a new pixel for each point in the image as a linear combination of the surrounding beamformed pixels. The weights for each pixel are calculated in advance using a quadratically constrained least squares method to reduce PSF energy outside the mainlobe and noise energy. Simulations indicate that this method can increase cystic contrast by up to 20dB without any cost in SNR, and can increase pixel SNR can by up 16dB without affecting contrast. Alternatively, simultaneous gains in contrast and SNR can be achieved. Experimental results show smaller performance improvements yet validate the feasibility of this technique.
Photoaffinity labeling of a novel benzodiazepine binding protein in rat brain.

Abstract Photoaffinity labeling experiments were conducted with [ 3 H]clonazepam to investigate the possible existence of a benzodiazepine binding site that is distinct from the central- and peripheral-type benzodiazepine binding sites. These studies demonstrate the presence of a novel benzodiazepine binding protein in rat brain with a relative mobility of 65 000 daltons that binds benzodiazepines stereoselectivity in the high nanomolar-low micromolar concentration range.
Fetal "nonreassuring status" is associated with elevation of nucleated red blood cell counts and interleukin-6.

Objective Previous studies have established the association between fetal hypoxia and elevated nucleated red blood cells (NRBCs). Animal studies have demonstrated that a rise in plasma erythropoietin (EPO) is not detectable until 4 to 6 hours after the initiation of hypoxia. In contrast, interleukin-6 (IL-6) has the capacity to directly induce erythroid maturation. Therefore, we set forth to evaluate the role of EPO and IL-6 as potential mediators of elevated fetal NRBCs in response to acute hypoxia. Study design Low-risk pregnancies with a normal fetal heart rate at admission to labor and delivery were eligible for participation. Deliveries for "nonreassuring fetal status" comprised the study group. All other deliveries served as controls. Umbilical cord blood was prospectively collected for blood gas analysis, NRBC counts, EPO, and IL-6. Results One hundred women participated in the study. Nonparametric univariate analysis demonstrated a significant association between elevated NRBC counts and Apgar scores, arterial cord blood pH, base excess, EPO, and IL-6 levels (all P values P values R 2 of 0.27, 0.42, and 0.46, respectively). A significant increase in NRBC counts was noted in study patients. IL-6 was significantly increased in study patients, whereas there was no difference in EPO between groups. Conclusion The fact that NRBC counts were elevated in fetuses who were delivered for "nonreassuring fetal status" with EPO being normal and IL-6 being elevated implies that IL-6 may have a unique, short-term role in elevating fetal NRBC counts.
Spontaneously broken continuous symmetries in hyperbolic (or open) de Sitter spacetime.

The functional Schr\"odinger approach is used to study scalar field theory in hyperbolic (or open) de Sitter spacetime. While on intermediate length scales (small compared to the spatial curvature length scale) the massless minimally coupled scalar field two-point correlation function does have a term that varies logarithmically with scale, as in flat and closed de Sitter spacetime, the spatial curvature tames the infrared behavior of this correlation function at larger scales in the open model. As a result, and contrary to what happens in flat and closed de Sitter spacetime, spontaneously broken continuous symmetries are not restored in open de Sitter spacetime (with more than one spatial dimension).
Clusterin in the male reproductive system: localization and possible function.

Abstract Clusterin is a glycoprotein that was initially isolated from the male reproductive system. Subsequently, clusterin has been found to be widely distributed in a variety of tissues in mammals. One characteristic of the expression of clusterin is that it is induced as a result of cellular injury, death, or pathology. Despite the efforts of many laboratories working in diverse biological systems, the function of clusterin remains unknown. Recent studies have revealed a ‘heat-shock element’ in the promoter of the gene that may account for the inducible nature of the clusterin gene. Overall, the evidence suggests that function of clusterin is to protect surviving cells after damage. This protection may result from a detergent-like action of the protein.