cssi/SciSciGPT-SciSciNet huggingface dataset:
Precision and reliability of periodically and quasiperiodically driven integrate-and-fire neurons

Neurons in the brain communicate via trains of all-or-none electric events known as spikes. How the brain encodes information using spikes---the neural code---remains elusive. Here the robustness against noise of stimulus-induced neural spike trains is studied in terms of attractors and bifurcations. The dynamics of model neurons converges after a transient onto an attractor yielding a reproducible sequence of spike times. At a bifurcation point the spike times on the attractor change discontinuously when a parameter is varied. Reliability, the stability of the attractor against noise, is reduced when the neuron operates close to a bifurcation point. We determined using analytical spike-time maps the attractor and bifurcation structure of an integrate-and-fire model neuron driven by a periodic or a quasiperiodic piecewise constant current and investigated the stability of attractors against noise. The integrate-and-fire model neuron became mode locked to the periodic current with a rational winding number $p/q$ and produced p spikes per q cycles. There were q attractors. $p:q$ mode-locking regions formed Arnold tongues. In the model, reliability was the highest during 1:1 mode locking when there was only one attractor, as was also observed in recent experiments. The quasiperiodically driven neuron mode locked to either one of the two drive periods, or to a linear combination of both of them. Mode-locking regions were organized in Arnold tongues and reliability was again highest when there was only one attractor. These results show that neuronal reliability in response to the rhythmic drive generated by synchronized networks of neurons is profoundly influenced by the location of the Arnold tongues in parameter space.
Damage Identification Using Electromagnetic Waves Based on Born Imaging Algorithm

Reconstructing damage geometry with computationally efficient and effective algorithms is of primary importance in establishing a robust structural health monitoring (SHM) system. In this paper, Born imaging algorithm is proposed for three-dimensional (3D) damage imaging of reinforced concrete structures using electromagnetic waves. This algorithm is derived in time domain for inhomogeneous isotropic and lossy structures. In order to reduce the computational cost of the algorithm, different imaging conditions are introduced. Numerical simulations in a 2D transverse magnetic case for a reinforced concrete slab with multiple damages are performed to test the effectiveness of the algorithm. In this simulated study, sensor data, incident field, and back-propagated field are computed via a finite difference time-domain method. It is concluded that the proposed imaging algorithm is capable of efficiently identifying the damages’ geometries and may be employed in a SHM system.
Clinical islet transplantation: advances and immunological challenges.

Type 1 diabetes mellitus results from autoimmune destruction of the insulin-secreting cells in the pancreas. Daily treatment with exogenous insulin is required, but because of difficulties in achieving physiological control of blood-glucose concentrations, chronic and degenerative complications still occur in a marked fraction of patients. Islet transplantation can normalize metabolic control in a way that has been virtually impossible to achieve with exogenous insulin, but life-long immunosuppression of the recipients is required, limiting the procedure to the most severe forms of diabetes. This article outlines the history of and recent progress in the field, as well as the present immunological challenges and possible strategies for tolerance induction that are crucial to make clinical islet transplantation more widely available.
Multimedia and Spinal Cord Injury: Educational Strategies for the 21st Century

Changes in the health care system and increasing demands by consumers for information and control over health decisions require a reevaluation of the educational strategies used in spinal cord injury rehabilitation. Interactive health communication applications, particularly Web sites and multimedia educational programs, are being used to meet these new educational needs. Digital education programs based on sound design guidelines and educational principles will provide valuable tools for consumers and professionals. The rapid developments in educational strategies and delivery technologies will result in new and increasingly effective solutions in the 21st century.
A Simple And Low Cost 3-Probe Measurement Technique Using Microstrip Circuits

A simple and low cost measurement system using 3-probe microstrip circuits has been developed for impedance and S-parameter measurements. The coupling coefficients for the three probes can be unequal and only one power meter is required. The measured results agree very well with those obtained from an HP 8510 automatic network analyzer.
Cell walls and synthetic fibers

Many theoretical chemists now discount much chemical and botanical work in cell wall research before 1920 and all current work which indicates the presence and importance of non-cellulosic materials in determining cell-wall properties.
Use of the protein A-gold immunocytochemical and enzyme-gold cytochemical techniques in studies of vitellogenesis.

Vitellogenesis in the frog hepatocyte was investigated by applying the protein A-gold immunocytochemical and RNase-gold cytochemical techniques in conjunction with morphometric and biochemical analyses. The morphometric studies demonstrated that the surface density of rough endoplasmic reticulum (RER) and nucleolar size increased more than fourfold and 1.25-fold, respectively, while the nuclear size and the mitochondrial compartment size remained constant following estrogen treatment. Concurrently, liver RNA concentration increased 2.5-fold while protein and DNA concentrations did not change. In addition, total plasma protein more than doubled, with vitellogenin accounting for 40% of the final volume. The secretory proteins vitellogenin and protein-RcX (a nonvitellogenin, estrogen-induced plasma protein of unknown function, found in the plasma of Rana catesbeiana) were detected immunocytochemically in the RER, Golgi apparatus, and secretory granules in hepatocytes only of estrogen-treated frogs. Lysosomes also were labeled. These observations established that protein-RcX was synthesized and secreted by the hepatocyte in parallel with vitellogenin and that both of these export proteins were confined to the secretory pathway and lysosomes. Quantitation of labeling density indicated that the concentration of vitellogenin increased as it progressed along the secretory vector. Albumin was detected immunocytochemically also within these same hepatocyte entities from both untreated and treated animals. In the untreated animals, albumin concentration also increased progressively along the secretory vector. A marked alteration of albumin processing was observed following estrogen treatment While albumin concentration in the RER was unchanged, its concentrations within the Golgi apparatus and secretory granules were lower than those observed in the RER or in counterpart compartments under control conditions. RNase-gold cytochemistry for total RNA demonstrated a 1.5-fold increase in labeling density over the nucleolus but no change in RER labeling following estrogen treatment. These labeling data, in combination with the morpho-metric data, suggest an increase of approximately 80% in the total amount of RNA in the nucleolus and 430% in the RER in response to estrogen. This review thus illustrates the significant contributions which can be made by gold-probe techniques, alone or in combination with morphometric and biochemical techniques, to investigations of the intracellular processing of secretory proteins.
The role of prediction in perception: Evidence from interrupted visual search.

Recent studies of rapid resumption—an observer’s ability to quickly resume a visual search after an interruption—suggest that predictions underlie visual perception. Previous studies showed that when the search display changes unpredictably after the interruption, rapid resumption disappears. This conclusion is at odds with our everyday experience, where the visual system seems to be quite efficient despite continuous changes of the visual scene; however, in the real world, changes can typically be anticipated based on previous knowledge. The present study aimed to evaluate whether changes to the visual display can be incorporated into the perceptual hypotheses, if observers are allowed to anticipate such changes. Results strongly suggest that an interrupted visual search can be rapidly resumed even when information in the display has changed after the interruption, so long as participants not only can anticipate them, but also are aware that such changes might occur.
Global Business Literacy in the Classroom: Developing and Applying an Assessment Framework.

This study develops and applies a framework to evaluate undergraduate Global Business Literacy (GBL) learning outcomes, which is defined here as the ability to adapt and function in the global business context and to be knowledgeable about its core issues and trends. As a first step in a multi-stage research process, we used extant expatriate and global business education literature to develop a 58-item survey. Exploratory factor analysis of pre-test survey data from 166 seniors revealed five explanatory factors that we labeled self-efficacy (SE), willingness to learn (WTL), relationship development (RD), technical competence (TC), and self-awareness (SA). Next, we used the framework to complete a post-test study of the effectiveness of a classroom-based Global Business Colloquium at improving students' perceived GBL. A paired-samples t-test revealed mean increases/decreases in scores from Time 1 to Time 2 on four factors: SE, WTL, RD, and TC, but no significant difference in SA. We discuss future researc...
The SOV >62; … >62; OSV frequency hierarchy

Abstract Typologists tend to agree that the numerical distribution of the six logically possible orderings of S, O and V across the world's languages is SOV >62; SVO >62; VSO >62; VOS >62; OVS >62; OSV. Starting with Peirce's proposal that semantic form is diagrammatic (iconic) in nature, we then argue that the semantic relations of S, O and V are best characterized as three concentric regions: S contained in O and O contained in V. Word order functions as a linear interpretation of this semantic diagram according to the ordering principles of figure/ground interpretation. These principles interact in such a way that all six ordering interpretations fall on a preference scale which conforms exactly to the SOV >62; … >62; OSV frequency hierarchy.
Magnetic auditory source imaging in macaque monkey

We recorded magnetic auditory evoked fields from the left hemisphere of a 2-year-old 3.4 kg Macaca nemestrina monkey. Three separate components were isolated from each of three data sets with latencies of approximately 22 ms, 46 ms, and 130 ms after stimulus onset. The 46 ms latency component had clear extrema values and was selected for localization. Field values from 21 recording points were used to estimate the 3-D source location of the 46 ms latency component, termed the M46. High resolution MR images of the brain provided information for correlation of neuroanatomic structure with source location. The neuroanatomic source was found to lie in the superior aspect of the temporal lobes bilaterally. We believe the M46 is the macaque analog of the human M100. Recording of auditory evoked fields in nonhuman primates offers a valuable animal model for studying neurophysiology of human magnetoencephalographically (MEG) determined auditory sources.
Al2O3/ADC12 Composites Fabricated by Decomposition-Synthesis Method and their Mechanical Behaviors

Aluminium matrix composites reinforced by Al2O3 particles has been produced by adding NH4AlO(OH)HCO3 into molten ADC12 Al-Si alloy, where the γ-Al2O3 reinforcement particles are formed by decomposing reaction of NH4AlO(OH)HCO3 during stirring. The results show that the Al2O3 particles are distributed more uniformly in the matrix than that by direct adding of Al2O3 particles. Hardness and wear properties have also been examined and the results show that the hardness of the composites increases with increasing volume fraction of the reinforced particles. Wear rate of the composites decreases with increasing volume fraction of the reinforced particles and increases with the applied load. The mechanical properties of the composites prepared by adding of NH4AlO(OH)HCO3 are superior and more wearable than that prepared by direct adding of Al2O3 particles. Wearing mechanism of the surfaces of the unreinforced alloy and composites is dominantly abrasive.
Quasi-Interpolation in Shift Invariant Spaces☆

Abstract Let s ≤ 1 be an integer, φ: R s → R be a compactly supported function, and S(φ) denote the linear span of {φ( · − k) : k ϵ Z s}. We consider the problem of approximating a continuous function f : R s → R on compact subsets of R s from the classes S(φ(h · )), h > 0, based on samples of the function at scattered sites in R s. We demonstrate how classical polynomial inequalities lead to the construction of local, quasi-interpolatory operators for this purpose.
Steric Turnoff of Vibrationally Mediated Negative Differential Resistance in a Single Molecule.

Negative differential resistance (NDR), mediated by vibrational excitation, is strongly dependent on molecular structure and dynamics, according to scanning tunneling microscopy on Cu(001)-bound pyrrolidine and N-methylpyrrolidine at 9 K. Tunneling electrons cause the former to switch between conformations I and II, so that NDR is observed. The methyl group of of the latter compound restricts it to a single conformation, and a linear current-voltage characteristic results.
Synergistic activity of granulocyte-macrophage colony-stimulating factor and 3'-azido-3'-deoxythymidine against human immunodeficiency virus in vitro.

Abstract The ability of granulocyte-macrophage colony-stimulating factor (GM-CSF) and 3'-azido-3'-deoxythymidine (AZT) to inhibit human immunodeficiency virus (HIV) in the U-937 monocytic cell line was examined. Acutely HIV-infected U-937 cells were exposed to GM-CSF (0.03, 0.3, 3.0, or 30.0 U/ml) and AZT (0.1, 1.0, or 10.0 microM) alone and in combination for 14 to 17 days. Reverse transcriptase activity in the supernatant, the percentage of cells expressing viral antigens by indirect immunofluorescence, and the 50% tissue culture infectious dose per milliliter of supernatant were determined to assess the level of viral replication in treated and control cultures. By the fractional-product method of analysis, nearly all combinations of GM-CSF and AZT synergistically inhibited HIV replication by these three measurements. The most effective combinations were 30 U of GM-CSF per ml with 0.1, 1.0, or 10.0 microM AZT. These treatments resulted in no reverse transcriptase activity in the supernatants, less than 1% immunofluorescent positive cells, and less than 8 50% tissue culture infectious doses per ml in the absence of cytotoxicity. Despite this degree of suppression, productive viral replication returned in all cultures within 4 to 10 days after drug removal. Combined therapy with GM-CSF and AZT merits consideration in the approach to HIV-associated illnesses.
Spinning Our Wheels: Improving Our Ability to Respond to Bullying and Cyberbullying

The 2005 Youth Risk BehaviorSurvey in Massachusetts found that 24% of teenagers reported being bullied atschools in the year before the survey. A study of 21,000 Massachusetts schoolchil-dren between October 2010 and February 2011 found that about one fourth ofmiddle- and high-schoolers reported being physically bullied, and more than doublethat number reported being taunted or called a name (
Diffusion-Controlled Charge Transfer from Excited Ru(bpy)32+ into Nanosized TiO2 Colloids Stabilized with EDTA

Transparent colloidal TiO2 was prepared in aqueous EDTA solution. The average particle size was 7 nm, measured by TEM. In the presence of EDTA, the colloids were stable within a pH range from 2 to 10. In contrast to previous observations involving Ru(bpy)32+ and TiO2 where no emission quenching occurred up to pH 10, an efficient quenching of the excited Ru(bpy)32+ (3MLCT) by the colloidal TiO2 was obtained in the presence of EDTA. A detailed kinetics investigation by laser flash photolysis showed the quenching process to be diffusion-controlled. The fact that not all the excited-state population returned to the ground state in a simple exponential process led to the conclusion that Ru(bpy)33+ was being formed and the quenching was by injection of electrons into the colloid. The overall quantum yield of formation of Ru(bpy)33+ was increased from 5.8% to 12.9% as the ionic strength increased from 0.1 to 1.5 M at pH 2.8. It was concluded that the increase in ionic strength weakens the electrostatic interacti...
Some Effects of Phosphon on Germination Induced by Red Radiation and Gibberellic Acid in Seeds of Verbascum thapsus.

In intact plants, growth retardants (1 ) yield a competitive type of interaction with gibberellins, and simiiulate the effects of brief red radiation treatmen-ts or slhort photoperiods of high irradiance in the inllibition of interniode extelnsioln. With reg,ard to seed germination, stich retardaints as Phosphon (2, 4-diclhlorobenzyl-tributvl phosphonium chloride) delaved but did not permaniently inihibit the germination of radiation-requiring seeds of Lepidium viroginhicumit induced by a radiation treatment (2). No interaction with the phytochrome system was observedl and possible interaction with gibberellin induction of germin-ation was not investigated. Primarily, this report concerns the effects of Phosphon on the germination of radiation-requiring seeds of Verbascumn thapsus (3), germination having been induced by brief radiation treatment or imbibition in solutions of potassium gibberellate (GA3).
Capital markets' assessment of airline restructuring following deregulation

The Airline Deregulation Act of 1978 propelled the industry into a constant state of change, even turmoil, that prevails 14 years later. The purpose of this paper is to examine the capital markets' reactions to the dramatic restructuring of the airline industry. The results of an event study of 24 merger announcements indicates that stockholders of target firms experience positive abnormal returns of 14.5% over a three-day period around the merger announcement date. Bidding firms experience a 3.7% increase over the same time window. Clearly, the capital markets viewed this restructuring of the industry as positive.
Treatment with genetically engineered fibroblasts producing NGF or BDNF can accelerate recovery from traumatic spinal cord injury in the adult rat

We tested the hypothesis that NGF or BDNF can protect damaged neural structures following spinal cord injury. Spinal contusions were produced in adult rats by a weight drop method. Thereafter, unmodified Rat 1 fibroblasts or fibroblasts engineered to secrete NGF or BDNF were injected into the injury site. Weekly assessments of recovery were made for 6 weeks using a locomotor rating scale. All rats were immediately paraplegic, then began to recover. At 1 week after injury, the ratings of locomotor performance in rats implanted with NGF- or BDNF-secreting fibroblasts were significantly increased over those of rats implanted with unmodified fibroblasts. This trend toward enhanced recovery persisted during the duration of the experiment, although the difference became smaller. Histological examination after 6 weeks showed a larger cross-sectional area of spinal cord at the maximal injury site in the animals treated with NGF or BDNF. These results demonstrate a significant biological effect of treatment with neurotrophins in traumatic spinal cord injury.
Negative-ion formation in n-nonanol

Abstract Negative-ion fragments from five isomers of n-nonanol and 2-propanol have been observed for both high- (70 eV) and low-energy (6–15 eV) electron impact. In the lower energy range several resonant dissociative attachment (DA) processes have been observed. For 2-propanol, resonance maxima were found at 9.5 and 11.3 eV for O−, with a third maximum at 6.6 eV shown to be due to background O2. Additionally, a resonance at 8.6 eV was found for OH− from 2-propanol. Fragments at m/z 1, 16, 17 and 141 were found to have resonant DA processes for all five nonanol isomers. These resonance maxima do not change with OH position. DA processes observed at m/z 57, 71, 85 and 99 were found to correlate with OH position and may be used to identify the particular isomer under study. These resonances all occur at 8.0 eV and are interpreted as having a common excited precursor state which decays through open channels determined by the OH position. For 70 eV electrons, the mass spectra show isomeric differences in peaks in the range m/z 49–137.
Drugs affecting homocysteine metabolism: impact on cardiovascular risk.

Elevated total plasma homocysteine has been established as an independent risk factor for thrombosis and cardiovascular disease. A strong relationship between plasma homocysteine levels and mortality has been reported in patients with angiographically confirmed coronary artery disease. Homocysteine is a thiol containing amino acid. It can be metabolised by different pathways, requiring various enzymes such as cystathionine β-synthase and methylenetetrahydrofolate reductase. These reactions also require several co-factors such as vitamin B6 and folate. Medications may interfere with these pathways leading to an alteration of plasma homocysteine levels. Several drugs have been shown to effect homocysteine levels. Some drugs frequently used in patients at risk of cardiovascular disease, such as the fibric acid derivatives used in certain dyslipidaemias and metformin in type 2 (non-insulin-dependent) diabetes mellitus, also raise plasma homocysteine levels. This elevation poses a theoretical risk of negating some of the benefits of these drugs. The mechanisms by which drugs alter plasma homocysteine levels vary. Drugs such as cholestyramine and metformin interfere with vitamin absorption from the gut. Interference with folate and homocysteine metabolism by methotrexate, nicotinic acid (niacin) and fibric acid derivatives, may lead to increased plasma homocysteine levels. Treatment with folate or vitamins B6 and B12 lowers plasma homocysteine levels effectively and is relatively inexpensive. Although it still remains to be demonstrated that lowering plasma homocysteine levels reduces cardiovascular morbidity, surrogate markers for cardiovascular disease have been shown to improve with treatment of hyperhomocystenaemia. Would drugs like metformin, fibric acid derivatives and nicotinic acid be more effective in lowering cardiovascular morbidity and mortality, if the accompanying hyperhomocysteinaemia is treated? The purpose of this review is to highlight the importance of homocysteine as a risk factor, and examine the role and implications of drug induced modulation of homocysteine metabolism.
A Chemometric Approach for Predicting the Size of Magnetic Spinel Ferrite Nanoparticles from the Synthesis Conditions

Magnetic CoFe2O4 spinel ferrite nanoparticles are synthesized by a microemulsion method using sodium dodecyl sulfate as the surfactant to form micelles. A statistical method of factorial design is used to establish a mathematical model from a series of synthesis experiments. This chemometric model quantitatively correlates the size of the nanoparticles with the experimental conditions. It has demonstrated the capability of predicting the mean diameter of nanoparticles from the synthesis conditions with a precision of 1−3 nm over a range from 5 to 35 nm. This quantitative correlation between the size of nanoparticles and the synthesis condition provides the rationale for choosing experimental conditions to control the nanoparticle sizes.
The number of caterpillars

A caterpillar is a tree which metamorphoses into a path when its cocoon of endpoints is removed. The number of nonisomorphic caterpillars with n+4 points is 2^n + 2^[^n^2^]. This neat formula is proved in two ways: first, as a special case of an application of Polya's enumeration theorem which counts graphs with integer-weighted points; secondly, by an appropriate labeling of the lines of the caterpillar.
Block preconditioning for saddle point systems with indefinite (1, 1) block

We investigate the solution of linear systems of saddle point type with an indefinite (1, 1) block by preconditioned iterative methods. Our main focus is on block matrices arising from eigenvalue problems in incompressible fluid dynamics. A block triangular preconditioner based on an augmented Lagrangian formulation is shown to result in fast convergence of the GMRES iteration for a wide range of problem and algorithm parameters. Some theoretical estimates for the eigenvalues of the preconditioned matrices are given. Inexact variants of the preconditioner are also considered.
Program Fragmentation as a Metamorphic Software Protection

Unauthorized reverse-engineering of programs and algorithms is a major problem for the software industry. Reverse-engineers search for security holes in the program to exploit or try to steal competitors' vital algorithms. To discourage reverse-engineering, developers use a variety of static software protections to obfuscate their programs. Metamorphic software protections add another layer of protection to traditional static obfuscation techniques, forcing reverse-engineers to adjust their attacks as the protection changes. Program fragmentation combines two obfuscation techniques, outlining and obfuscated jump tables, into a new, metamorphic protection. Sections of code are removed from the main program flow and placed throughout memory, reducing the program's locality. These fragments move and are called using obfuscated jump tables, making program execution difficult to follow. This research assesses the performance overhead of a program fragmentation engine and provides analysis of its effectiveness against reverse-engineering techniques. Results show that program fragmentation has low overhead and is an effective technique to complicate disassembly of programs using two common disassembler/debugger tools.
Cue integration with categories: Weighting acoustic cues in speech using unsupervised learning and distributional statistics.

During speech perception, listeners make judgments about the phonological category of sounds by taking advantage of multiple acoustic cues for each phonological contrast. Perceptual experiments have shown that listeners weight these cues differently. How do listeners weight and combine acoustic cues to arrive at an overall estimate of the category for a speech sound? Here, we present several simulations using a mixture of Gaussians models that learn cue weights and combine cues on the basis of their distributional statistics. We show that a cue-weighting metric in which cues receive weight as a function of their reliability at distinguishing phonological categories provides a good fit to the perceptual data obtained from human listeners, but only when these weights emerge through the dynamics of learning. These results suggest that cue weights can be readily extracted from the speech signal through unsupervised learning processes.
Effect of temperature on oil/water relative permeabilities of unconsolidated and consolidated sands

Over the last 20 years, a number of studies have reported temperature effects on two-phase relative permeabilities in porous media. However, some of the reported results have been contradictory. Also, observed effects have not been explained in terms of fundamental properties known to govern two-phase flow. The purpose of this study was to attempt to isolate the fundamental properties affecting two-phase relative permeabilities at elevated temperature. Laboratory dynamic displacement relative permeability measurements were made on unconsolidated and consolidated sand cores, using water and a refined white mineral oil. Experiments were run on 2 in. (51 mm) diameter, 20 in. (510 mm) long cores from room temperature to 300/sup 0/F (149/sup 0/C). Unlike the results of previous researchers, essentially no changes with temperatures were observed in either residual saturations or relative permeability relationships. It was concluded that previous results may have been affected by viscous instabilities, capillary end-effects, and/or difficulties in maintaining material balances.
Stability of switched linear systems on non-uniform time domains

A recent development in Lyapunov stability theory allows for analysis of switched linear systems evolving on nonuniform, discrete time domains. The analysis makes use of an emerging mathematical framework termed dynamic equations on time scales. We will present stability conditions for a general, arbitrarily switched system and then for system with a “constrained” switching signal. The results take the form of a compute-able inequality, which imposes conditions on the time domain itself.
Failure to decrease parasympathetic tone during upright tilt predicts a positive tilt-table test

The most frequently proposed mechanism for vasodepressor syncope is based on cardiac mechanoreceptor activation by augmented sympathetic tone. Because of the central role of the autonomic nervous system in this response, we hypothesized that the responses of the sympathetic and parasympathetic nervous systems (as assessed by analysis of heart rate variability) to orthostatic stress would differentiate patients with a positive from those with a negative tilt-table response. We therefore evaluated 28 patients undergoing tilt-table testing for presumed vasodepressor syncope. Based on 5-minute electrocardiographic samples obtained during the supine and upright phases (without isoproterenol infusion), we computed the mean RR interval, reflecting integrated cardiac sympathetic and parasympathetic tone, as well as the root-mean-square of successive differences of the RR intervals (RMSSD), a measure of high-frequency heart rate variability that is correlated with parasympathetic tone. Eleven patients had a negative and 17 a positive tilt response. There were no differences between the groups at baseline. In response to upright tilt, the mean RR decreased by a similar magnitude in both groups. In contrast, RMSSD decreased by 36% (p = 0.05) in response to upright tilt in patients with a negative response, but did not change significantly in patients with a positive tilt response. Absence of a decrease in RMSSD in response to orthostatic stress had 100% specificity and 41% sensitivity for predicting a positive test result. Thus, failure of withdrawal of parasympathetic tone (as assessed by RMSSD) during upright tilt predicts a positive tilt response.(ABSTRACT TRUNCATED AT 250 WORDS)
A combined deterministic and sampling-based sequential bounding method for stochastic programming

We develop an algorithm for two-stage stochastic programming with a convex second stage program and with uncertainty in the right-hand side. The algorithm draws on techniques from bounding and approximation methods as well as sampling-based approaches. In particular, we sequentially refine a partition of the support of the random vector and, through Jensen's inequality, generate deterministically valid lower bounds on the optimal objective function value. An upper bound estimator is formed through a stratified Monte Carlo sampling procedure that includes the use of a control variate variance reduction scheme. The algorithm lends itself to a stopping rule theory that ensures an asymptotically valid confidence interval for the quality of the proposed solution. Computational results illustrate our approach.
Equations on the Derivatives of an Initial Endowment-Competitive Equilibrium Mapping for an Exchange Economy

Consider an exchange economy with n traders and k goods. Suppose that there exists C 2 mappings p(· )a ndx(· )t hat specify for each initial endowment w of the k goods to the n traders a price vector p(w) and a vector of net trades x(w )t hat deÞne a competitive equilibrium. Three systems of determinant equations are derived that the derivatives of p(· )a ndx(·) necessarily satisfy regardless of the underlying preferences that determine these mappings. Each of the three systems of equations fundamentally resects the interaction among traders in the competitive mechanism.
The zenith‐camera for geographic location

Engineers and astronomers are already familiar with the use of the transit and theodolite for field-determination of latitude and longitude. In recent years the prismatic astrolabe or equiangulator has come into extensive use by the Army Air Forces for the determination of geographic positions [see Trans. Amer. Geophys. Union, Part II, pp. 199–207,1942]. The latest instrument developed for this purpose is a camera which photographs a portion of the sky immediately surrounding the zenith. The finished photographic plate shows the stars in the vicinity of the zenith and a fiducial mark which represents the zenith itself. The camera takes a 4- by 5-inch glass plate and exposes a square field approximately 9.°5 on a side. From measurements on the plate and computations it is possible to deduce the position of the zenith from its relationship to the known positions of identifiable stars in the photograph (see Fig. 1).
Promoting Heterogeneity, Mobility, and Energy-Aware Voronoi Diagram in Wireless Sensor Networks

Static always-on wireless sensor networks (WSNs) are affected by the energy sink-hole problem, where sensors nearer a central gathering node, called the sink, suffer from significant depletion of their battery power (or energy). It has been shown through analysis and simulation that it is impossible to guarantee uniform energy depletion of all the sensors in static uniformly distributed always-on WSNs with constant data reporting to the sink when the sensors use their nominal communication range to transmit data to the sink. We prove that the energy sink-hole problem can be solved provided that the sensors adjust their communication ranges. This solution, however, imposes a severe restriction on the size of a sensor field. To overcome this limitation, we propose a sensor deployment strategy based on energy heterogeneity with a goal that all the sensors deplete their energy at the same time. Simulation results show that such a deployment strategy helps achieve this goal. To solve the energy sink-hole problem for homogeneous WSNs, we propose a localized energy-aware-Voronoi-diagram-based data forwarding (EVEN) protocol. EVEN combines sink mobility with a new concept, called energy-aware Voronoi diagram. Through simulations, we show that EVEN outperforms similar greedy geographical data forwarding protocols and has performance that is comparable to that of an existing data collection protocol that uses a joint mobility and routing strategy. Precisely, we find that EVEN yields an improvement of more than 430 percent in terms of network lifetime.
Volume Learning: Signaling Covariance Through Neural Tissue

The finding that rapidly diffusible chemical signals produced at post-synaptic terminals can cause changes in efficacy at spatially distant pre-synaptic terminals completely alters the framework into which Hebbian learning fits. These signals diffuse through the extra-synaptic space to alter synaptic efficacies under appropriate contingencies. We have analysed the resulting model of plasticity within a volume of neural tissue. As a special case, we show that rather than having the scale of developing cortical structures such as ocular dominance columns set by intrinsic cortical connectivity, it is set by a more dynamic process tying diffusion and pre-synaptic activity.
Identifying Innovative Agricultural Education Programs

According to the National Research Agenda for Agricultural Education (Doerfert, 2011), research priority five builds the case for efficient and effective agricultural education programs. Priority five goes on to state our scientific focus should, “Define characteristics of effective agricultural education programs and teachers and the means to correctly access the current state of these characteristics” (p.10). One approach to achieving this goal is to identify and replicate sustainable innovative program designs.
Dengue-associated kidney disease.

Context: A mosquito-borne viral illness highly prevalent in the tropics and subtropics, dengue is considered a major global health threat by the World Health Organization. Evidence Acquisitions: Directory of Open Access Journals (DOAJ), Google Scholar, PubMed (NLM), LISTA (EBSCO) and Web of Science have been searched. Results: An RNA virus from the genus Flavivirus, dengue virus is transmitted by Aedes aegypti, the yellow fever mosquito. Dengue is asymptomatic in as many as one half of infected individuals. Dengue fever is an acute febrile illness accompanied by constitutional symptoms. Dengue hemorrhagic fever and dengue shock syndrome are the severe forms of dengue infection. Dengue infection has been associated with a variety of renal disorders. Acute renal failure is a potential complication of severe dengue infection and is typically associated with hypotension, rhabdomyolysis, or hemolysis. Acute renal failure complicates severe dengue infection in 2-5% of the cases and carries a high mortality rate. Proteinuria has been detected in as high as 74% of patients with severe dengue infection. Hematuria has been reported in up to 12.5% of patients. Various types of glomerulonephritis have been reported during or shortly after dengue infection in humans and mouse models of dengue infection. Mesangial proliferation and immune complex deposition are the dominant histologic features of dengue-associated glomerulonephritis. On a rare occasion, dengue infection is associated with systemic autoimmune disorders involving the kidneys. Conclusions: In the vast majority of cases, dengue infection and associated renal disorders are self-limited. Short-Review
Monte Carlo studies of the fundamental limits of the intrinsic hyperpolarizability

The off-resonant hyperpolarizability is calculated by using the dipole-free sum-over-states expression from a randomly chosen set of energies and transition dipole moments that are forced to be consistent with the sum rules. The process is repeated so that the distribution of hyperpolarizabilities can be determined. We find this distribution to be a cycloidlike function. In contrast to variational techniques that when applied to the potential energy function yield an intrinsic hyperpolarizability less than 0.71, our Monte Carlo method yields values that approach unity. While many transition dipole moments are large when the calculated hyperpolarizability is near the fundamental limit, only two excited states dominate the hyperpolarizability—consistent with the three-level ansatz. We speculate on the character of the Hamiltonian that is needed to optimize the intrinsic hyperpolarizability.
Strontium isotopic anomalies in the Allende Meteorite

We report isotopic anomalies in Ca which were found in two Ca-Al-rich inclusions of the Allende meteorite. These inclusions previously had been shown to contain special anomalies for Mg and O which were attributed to fractionation and unknown nuclear effects. The Ca data, when corrected for mass fractionation by using ^(40)Ca/^(44)Ca as a standard show nonlinear isotopic effects in ^(48)Ca of + 13.5 per mil and in ^(42)Ca of +1.7 per mil for one sample. The second sample shows a ^(48)Ca depletion of - 2.9 per mil, but all other Isotopes are normal. Samples with large excesses in ^(26)Mg show no Ca anomalies. The effects demonstrate that isotopic anomalies exist for higher-atomic-number refractory elements in solar-system materials and do not appear to be readily explainable by a simple model. The correlation of O, Mg, and Ca results on the same inclusions requires the addition and preservation in the solar system of components from diverse nucleosynthetic sources. Observed anomalous Mg. and Ca compositions for coexisting mineral phases are uniform within each inclusion, and require initial isotopic homogeneity within an inclusion but the preservation of wide variations between inclusions. Assumming formation of these inclusions by condensation from a gaseous part of the solar nebula, this Implies Isotopic heterogeneity on a scale of 10-10^2 km within the nebula.
Functional Outcomes Following Single-Event Multilevel Surgery of the Upper Extremity for Children with Hemiplegic Cerebral Palsy

Background: Outcomes following single-event multilevel surgery of the upper extremity for children with cerebral palsy have not been well described in the literature. Since 1996, all children with hemiplegic cerebral palsy at our institution thought to be candidates for upper extremity surgery have had serial Shriners Hospital for Children Upper Extremity Evaluation performed for both clinical decision making and outcome assessment. The goal of the current study was to determine the functional outcomes, as described by the Shriners Hospital for Children Upper Extremity Evaluation, following single-event multilevel surgery of the upper extremity in children with hemiplegic cerebral palsy. Methods: The study design was a retrospective, case-control series. The case group consisted of forty children with hemiplegic cerebral palsy who underwent upper-extremity single-event multilevel surgery. The control group consisted of twenty-six children with hemiplegic cerebral palsy who had not received any upper-extremity interventions. The spontaneous functional analysis, dynamic positional analysis, and grasp-release analysis sections of the Shriners Hospital for Children Upper Extremity Evaluation were compared between the two groups. Results: The operative and nonoperative groups were comparable with respect to age (p = 0.09), sex (p = 0.97), initial spontaneous functional analysis scores (p = 0.37), dynamic positional analysis scores (p = 0.73), and grasp-release analysis scores (p = 0.16). For the single-event multilevel surgery group, significant improvements were noted for the mean spontaneous functional analysis score (p < 0.0001) and the mean dynamic positional analysis score (p < 0.0001), but not the mean grasp-release analysis score (p = 0.75). For the nonoperative control group, no significant changes were noted for the mean spontaneous functional analysis score (p = 0.89), the mean dynamic positional analysis score (p = 0.98), or the mean grasp-release analysis score (p = 0.36). Significant differences were noted between the single-event multilevel surgery and nonoperative control groups for the mean changes in the spontaneous functional analysis score (p = 0.01) and the mean change in the dynamic positional analysis score (p < 0.0001), but not the mean changes in the grasp-release analysis score (p = 0.56). Conclusions: Children with hemiplegic cerebral palsy showed significantly improved dynamic segmental alignment and, to a lesser degree, spontaneous use of the upper extremity following single-event multilevel surgery compared with a comparable nonoperative control group. However, the grasp-release ability did not significantly improve in either the operative or nonoperative group.
Histoplasma capsulatum, lung infection and immunity

Histoplasma capsulatum, an environmental fungus, is the most common endemic pulmonary mycosis in the USA. Disease is most frequently observed in immunocompromised patients living in endemic areas. We present the mechanisms of fungal recognition, innate immune response and adaptive immune response that lead to protection or exacerbation of disease. Current understanding of these mechanisms is the result of a continuing dialogue between clinical observations and murine studies. Mice are a powerful model to study the immune response to H. capsulatum alone or in the presence of immunomodulatory drugs. Vigilance for histoplasmosis should be exercised with novel immunosuppressive agents that target the important immune pathways identified here.
Numerical computation of three-dimensional circulation in Lake Erie - A comparison of a free-surface model and a rigid-lid model

Abstract The three-dimensional time-dependent flow in the Western Basin of Lake Erie has been calculated numerically by means of both a two-mode free-surface model and a rigid-lid model. Detailed comparisons of the results from these two models are presented for two wind conditions: 1) a constant wind suddenly imposed, and 2) an actual wind which is variable in both space and time. For relatively short time intervals, significant differences between the results of the two models occur since the seiche motion is eliminated in the rigid-lid model. Long-term time-averaged circulation computed by the two models agree well in periods of strong wind, but differ appreciably in periods of light wind and active seiching.
Deletion of Individual Exons and Induction of Soluble Murine Interleukin-5 Receptor-α Chain Expression through Antisense Oligonucleotide-Mediated Redirection of Pre-mRNA Splicing

Expression of the interleukin-5 receptor-α (IL-5Rα) chain is thought to play an important role in the pathogenesis of asthma and other eosinophilic diseases. With antisense oligonucleotides (ASOs) chemically modified to provide increased hybridization affinity for RNA but that do not support RNase H-mediated cleavage (2′-O-methoxyethyl-modified ASOs), we show that constitutive splicing of murine IL-5Rα mRNA can be modulated in cells such that individual exons may be selectively deleted from mature transcripts. Specific deletion of individual exons and redirection of alternative splicing of the IL-5Rα mRNA have been achieved with this approach, by targeting 3′-splice sites or exon sequences immediately downstream of an alternative splice site. ASO targeting with these strategies resulted in inhibition of mRNA and protein levels of the membrane IL-5Rα isoform capable of signaling IL-5-mediated growth and antiapoptotic signals to eosinophils. Membrane isoform IL-5Rα inhibition was coupled with an increase in expression of mRNA for the alternatively spliced soluble isoform, which binds IL-5 extracellularly and may block its function. These observations suggest the potential general therapeutic use of an antisense approach to increase expression of variant RNA transcripts and to thereby produce proteins devoid of specific functional domains that may impact disease processes, as well as its specific utility for modulating expression of a key cytokine receptor implicated in allergic inflammation.
Quantum Gravity in 2+1 Dimensions: Classical general relativity in 2+1 dimensions

If we wish to quantize (2+1)-dimensional general relativity, it is important to first understand the classical solutions of the Einstein field equations. Indeed, many of the best-understood approaches to quantization start with particular representations of the space of solutions. The next three chapters of this book will therefore focus on classical aspects of (2+1)-dimensional gravity. Our goal is not to study the detailed characteristics of particular solutions, but rather to develop an understanding of the generic properties of the space of solutions. In this chapter, I will introduce two fundamental approaches to classical general relativity in 2+1 dimensions. The first of these, based on the Arnowitt–Deser–Misner (ADM) decomposition of the metric, is familiar from (3+1)-dimensional gravity; the main new feature is that for certain topologies, we will be able to find the general solution of the constraints. The second approach, which starts from the first-order form of the field equations, is also similar to a (3+1)-dimensional formalism, but the first-order field equations become substantially simpler in 2+1 dimensions. In both cases, the goal is to set up the field equations in a manner that permits a complete characterization of the classical solutions. The next chapters will describe the resulting spaces of solutions in more detail. I will also derive the algebra of constraints in each formalism – a vital ingredient for quantization – and I will discuss the (2+1)-dimensional analogs of total mass and angular momentum.