cssi/SciSciGPT-SciSciNet huggingface dataset:
Hydraulic Conductivity of Saprolite as a Function of Sample Dimensions and Measurement Technique

Accurate hydraulic conductivity (K) data are needed to evaluate soils for on-site waste disposal, but such data are difficult to obtain where K values vary with sample dimensions. This study evaluated the K of a quartz-diorite saprolite (Cl horizon) by comparing saturated hydraulic conductivities (Kₛₐₜ) for sample volumes of 347, 6280, and 675000 cm³. Unsaturated hydraulic conductivities [K(h)] for sample volumes of 347 and 6280 cm³ were compared using a one-step outflow procedure and the crust test. A dye was also applied to the largest samples to determine the depth distribution of water-conducting macropores. The mean Kₛₐₜ value found for samples with volumes of 347 cm³ (0.04 cm h⁻¹) was significantly lower than the mean Kₛₐₜ values found for larger samples (0.16–0.20 cm h⁻¹); means for the latter samples were not significantly different (P = 0.10). Means for K(h) also differed between the two sample volumes for soil water pressure heads of −5 and −10 cm. Channels were the major kind of water-conducting macropore observed. The results from both the pore studies and K measurements showed that the minimum sample size needed in situ for K measurements in this horizon was ≈ 5000 cm³ for soil water pressure heads between 0 and −10 cm. Detached cores with smaller cross-sectional areas could be used for measuring K(h) at soil water pressure heads of -20 cm or less. The research was funded by Grant no. 70121 from the Water Resources Research Inst. of the Univ. of North Carolina. The use of trade names in this publication does not imply endorsement by the North Carolina Agricultural Research Service of the product named, nor criticism of similar ones not mentioned.
Improved pronunciation features for construct-driven assessment of non-native spontaneous speech

This paper describes research on automatic assessment of the pronunciation quality of spontaneous non-native adult speech. Since the speaking content is not known prior to the assessment, a two-stage method is developed to first recognize the speaking content based on non-native speech acoustic properties and then forced-align the recognition results with a reference acoustic model reflecting native and near-native speech properties. Features related to Hidden Markov Model likelihoods and vowel durations are extracted. Words with low recognition confidence can be excluded in the extraction of likelihood-related features to minimize erroneous alignments due to speech recognition errors. Our experiments on the TOEFL® Practice Online test, an English language assessment, suggest that the recognition/forced-alignment method can provide useful pronunciation features. Our new pronunciation features are more meaningful than an utterance-based normalized acoustic model score used in previous research from a construct point of view.
High Probe Intensity Photobleaching Measurement of Lateral Diffusion in Cell Membranes

Lateral diffusion measurements, most commonly accomplished through Fluorescence Photobleaching Recovery (FPR or FRAP), provide important information on cell membrane molecules' size, environment and participation in intermolecular interactions. However, serious difficulties arise when these techniques are applied to weakly expressed proteins of either of two types: fusions of membrane receptors with visible fluorescent proteins or membrane molecules on autofluorescent cells. To achieve adequate sensitivity in these cases, techniques such as interference fringe FPR are needed. However, in such measurements, cytoplasmic species contribute to the fluorescence recovery signal and thus yield diffusion parameters not properly representing the small number of surface molecules. A new method helps eliminate these difficulties. High Probe Intensity (HPI)-FPR measurements retain the intrinsic confocality of spot measurements to eliminate interference from fluorescent cytoplasmic species. However, HPI-FPR methods lift the previous requirement that FPR procedures be performed at probe beam intensities low enough to not induce bleaching in samples during measurements. The high probe intensities now employed provide much larger fluorescence signals and thus more information on molecular diffusion from each measurement. We report successful measurement of membrane dynamics by this technique.
Estrogen promotes learning-related plasticity by modifying the synaptic cytoskeleton.

Estrogen's acute, facilitatory effects on glutamatergic transmission and long-term potentiation (LTP) provide a potential explanation for the steroid's considerable influence on behavior. Recent work has identified mechanisms underlying these synaptic actions. Brief infusion of 17s-estradiol (E2) into adult male rat hippocampal slices triggers actin polymerization within dendritic spines via a signaling cascade beginning with the GTPase RhoA and ending with inactivation of the filament-severing protein cofilin. Blocking this sequence, or actin polymerization itself, eliminates E2's effects on synaptic physiology. Notably, the theta burst stimulation used to induce LTP activates the same signaling pathway as E2 plus events that stabilize the reorganization of the sub-synaptic cytoskeleton. These observations suggest that E2 elicits a partial form of LTP, resulting in an increase of fast excitatory postsynaptic potentials (EPSPs) and a reduction in the threshold for lasting synaptic changes. While E2's effects on the cytoskeleton could be direct, results described here indicate that the hormone activates synaptic tropomyosin-related kinase B (TrkB) receptors for brain-derived neurotrophic factor (BDNF), a releasable neurotrophin that stimulates the RhoA to cofilin pathway. It is therefore possible that E2 acts via transactivation of neighboring receptors to modify the composition and structure of excitatory contacts. Finally, there is the question of whether a loss of acute synaptic actions contributes to the memory problems associated with estrogen depletion. Initial tests found that ovariectomy in middle-aged rats disrupts RhoA signaling, actin polymerization, and LTP consolidation. Acute applications of E2 reversed these defects, a result consistent with the idea that disturbances to actin management are one cause of behavioral effects that emerge with reductions in steroid levels.
Epithelioid hemangioma of the spine: an uncommon cause of spinal cord compression.

A 65-year-old female presents to the emergency room with worsening mid-back pain, rapidly progressive numbness starting from below the breasts (T5 sensory level), and bilateral lower extremity weakness. She reported increasing difficulty ambulating and was unsteady on her feet. She had radiating pain into her anterior thighs, occasionally extending into her calves, right greater than left and had new-onset loss of sphincter, bowel and bladder control. Her focused neurologic exam showed quadriceps strength of 4?/5 on the left and 4-/5 on the right. Ankle dorsiflexion was 4-/5 bilaterally. She had a known history of midthoracic back pain for the preceding 4 months. She denied any history of remote or recent spinal trauma. Spinal cord compression was suspected and the initial CT imaging revealed a large lytic lesion at the T7–8 level with involvement of the corresponding ribs. Coronal imaging revealed destruction, expansion and trabeculation of the vertebral bodies of T7–9 and loss of vertebral body height. On axial imaging, there was paravertebral soft tissue extension with central canal narrowing (Figs. 1, 2, 3). An initial differential diagnosis of vascular tumor versus malignancy was considered and a CT-guided biopsy with angiographic embolization of feeding vessels was planned urgently, followed by definitive surgical intervention. She underwent an uneventful biopsy and successful Onyx-18 (eV3, Irvine, California, USA) embolization of feeding vessels (Fig. 3). The post-embolization surgical procedure involved laminectomies from T6 to T9, T7–8 vertebroplasty and partial transpedicular vertebrectomies followed by tumor resection with T4–T11 arthrodesis and posterior spinal fusion (Figs. 4, 5). She regained motor strength within 48 h and near complete resolution of numbness postoperatively. Final pathology was consistent with epithelioid hemangioma (EH).
Nonideal transport of reactive solutes in heterogeneous porous media : 2. Quantitative analysis of the Borden natural-gradient field experiment

Abstract Field experiments constitute an integral component of research on transport and fate of contaminants in the subsurface. One of the most well known of the few field experiments performed with reactive solutes is the natural-gradient experiment conducted at the Borden site during 1982 to 1984. A major finding of the experiment was that the transport of the reactive, organic compounds was nonideal. First, the velocities of the centers of mass of the plumes decreased with time, which was reflected in a temporal increase in effective retardation. Second, the longitudinal spreading observed for the organic solutes was about three times larger than that of the nonreactive tracers for an equivalent travel distance. Third, the breakthrough curves measured at selected monitoring points exhibited greater asymmetry compared to the nonreactive tracers. The cause(s) of the nonideal transport observed for the organic solutes has remained unexplained, despite a number of attempts. We have used a multi-scale, multi-factor mathematical model to successfully predict the displacement and spreading behavior of the tetrachloroethene and tetrachloromethane plumes. Based on our analyses, we conclude that a near-field trend of increasing sorption capacity was a primary cause of the deceleration of the centers of mass of the organic-solute plumes. The coupled effects of nonlinear sorption and enhanced spreading caused by spatially variable hydraulic conductivity and spatially variable sorption also influenced plume displacement. In addition, it is possible that the combination of spatially variable hydraulic conductivity and sorption contributed directly to plume deceleration. However, a magnitude of sorption variability larger than has been measured to date is required for this contribution to be significant. The combined spatial variability of hydraulic conductivity and sorption, and a potential negative cross correlation between them, appears to have been the major cause of the enhanced longitudinal spreading observed for the organic-solute plumes in comparison to the nonreactive-solute plumes. However, nonlinear sorption, the spatial trend of increasing sorption capacity, and rate-limited sorption/mass transfer also influenced spreading behavior. In total, it is evident that the transport of the organic compounds during the Borden natural-gradient field experiment was influenced by several interacting factors and coupled processes, and that accurate prediction of the observed behavior requires the use of a mathematical model that accounts for this complexity.
Gas-phase electron diffraction studies of some iron carbonyl complexes

Abstract Gas phase electron diffraction studies have been made of the complexes: butadieneiron tricarbonyl, cyclobutadieneiron tricarbonyl and ethyleneiron tetracarbonyl. In each instance the conformation was determined and values were obtained for the principal bond lengths and angles.
Hypogonadism, ADAM, and hormone replacement.

Male hypogonadism, or testosterone deficiency syndrome (TDS), results from a failure of the testes to produce adequate androgen. Patients have low circulating testosterone in combination with clinical symptoms such as fatigue, erectile dysfunction, and body composition changes. The cause may be primary (genetic anomaly, Klinefelter’s syndrome) or secondary (defect in hypothalamus or pituitary), but often presents with the same symptomatology. In the older patient, androgen deficiency of the aging male (ADAM) is an important cause of secondary hypogonadism because testosterone levels decline progressively after age 40. Hypogonadal patients have alterations not only in sexual function and body composition, but also in cognition and metabolism. Regardless of etiology, hypogonadal patients who are both symptomatic and who have clinically significant alterations in laboratory values are candidates for treatment. The goal of hormone replacement therapy in these men is to restore hormone levels to the normal range and to alleviate symptoms suggestive of hormone deficiency. This can be accomplished in a variety of ways, although most commonly testosterone replacement therapy (TRT) is employed.
Microfabricated ZnSe diffractive optical elements for CO 2 laser

We have developed a new design of advanced optics for processing high-power laser material. We introduce the concept of DOE for high power CO2 lasers. The superior functionality of DOE means that it could become the new standard in optics for next generation devices. Here we describe the design of our DOE technology using scalar theory and micro fabrication using photolithography and RIE. We also present results of our ZnSe-DOE technology, mainly focusing on a novel spot-array generator.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Headline Size and Position Influence on Consumers' Perception

In a laboratory experiment, the size of an advertising headline announcing a retail sale positively affected consumers' perception of the magnitude of the discount. When large print was used, subje...
Co-occurring insomnia and obstructive sleep apnea.

Study objectives: Prior research investigating co-occurring insomnia/obstructive sleep apnea (CIO) has mainly focused on comparing comorbid patients, obstructive sleep apnea (OSA), and insomnia (INS) to those with OSA alone. This approach is informative but omits the potentially interesting comparison of comorbid patients to those with INS alone. Our study used an incomplete factorial design, crossing OSA (present or absent) with INS (present or absent) to more clearly focus on the question, is comorbid INS an epiphenomenon of OSA or an independent disorder? Methods: Our study was an archival analysis from the database of a sleep center comparing consecutively diagnosed patients characterized as OSA or INS. A third group, CIO, was derived from the OSA group. Our study was conducted at an American Academy of Sleep Medicine–accredited sleep disorders center. We studied 299 patients, including 94 OSA, 97 INS, and 108 CIO. Patients ranged from ages 15 to 86 years. Results: Groups were compared on polysomnography (PSG), sleep pattern, sleep stages, sleep pathology, self-reported sleep concerns, and self-reported daytime functioning. From a consecutive group of OSA patients, we estimate the prevalence of CIO at 67.4%. Based mainly on multivariate analysis of covariance (MANCOVA) controlling for demographic differences between groups, we found few if any significant differences between CIO and INS alone or between CIO and OSA alone. Conclusions: The clinical presentation of CIO is indistinguishable from INS alone, both with respect to PSG findings and to self-reported sleep onset and sleep maintenance disturbance. We observed a weak relation between OSA severity and co-occurring INS. These data are consistent with the view that INS with co-occurring OSA is an independent, self-sustaining disorder. We hypothesized that in some unknown proportion of cases, OSA initially instigated the INS, but the INS was then perpetuated and reshaped by sleep concerns and self-defeating compensatory behaviors.
A study of combining heuristics for scheduling projects with limited multiple resources

Abstract The main objective of this study was to find a simple and quick procedure on the microcomputer for scheduling activities of a constrained multiple resource single project network that would minimize project duration. From this research there are two different types of results presented. First, a combination of simple heuristics which find the average of the minimum project durations for the constrained resource problem is presented. This combination not only supports the previous research on successful simple heuristic methods which set the priorities for constrained resource problems, but also produces results which are significantly better than those obtained by single heuristics. Second, a procedure for determining this combination of heuristics is introduced. A computer algorithm, COMAL, was developed for this study with constrained resource problems, but in the future its use may be expanded into other fields.
ANATOMIC DISTRIBUTION AND QUANTITATIVE DEVELOPMENTAL CHANGES IN GUINEA PIG PULMONARY BETA RECEPTORS

Quantitation using tissue homogenates has demonstrated an increase in pulmonary β-receptors during development. However, techniques using disrupted tissue have not permitted the precise anatomic localization of pulmonary β-receptors or identification of the structures where increases occur. Using 3H-dihydroalprenolol, β-receptors were radioautographically localized and quantitated in sections of newborn (NB) and adult (A) guinea pig lung. Specific binding on lung sections, defined as that prevented by 2μ M propranolol (80-90% of total counts), was rapid and saturable. Scatchard analysis showed a single class of binding sites with a maximum binding capacity of 189±3 (NB) and 305±37 (A) fmole/mg protein (p > bronchiolar > bronchial) (p<.0001) and averaged 2.8 (A) and 1.3 (NB)-fold greater in number than β-receptors in corresponding airway smooth muscle (p<.005). Arterial and venous smooth muscle had few demonstrable β-receptors. The increased number of β-receptors in the adult appeared to be due primarily to a 2.0±.2 fold increase in alveolar wall and airway epithelium as opposed to only a 1.3±.4 fold increase in the already low number in airway and vascular smooth muscle (p<.003). While receptor density may not necessarily correlate with response or physiologic importance, the role of β-receptors in airway and alveolar epithelium/endothelium function deserves further investigation.
Acid-Triggered Release via dePEGylation of Fusogenic Liposomes Mediated by Heterobifunctional Phenyl-Substituted Vinyl Ethers with Tunable pH-Sensitivity

A new family of heterobifunctional phenyl-substituted vinyl ether (PIVE) coupling agents with tunable acid-sensitivity has been developed. The PIVE compounds are designed to hydrolyze under acidic conditions with hydrolysis rates that can be varied by rational selection of the phenyl ring substituent. These reagents were incorporated within 2-methoxypoly(ethylene glycol) PEG-conjugated 1,3-dioctadecyl-rac-glycerol lipids to produce the acid-cleavable lipopolymers mPEG-[H-PIVE]-DOG, mPEG-[F-PIVE]-DOG, mPEG-[Me-PIVE]-DOG, and mPEG-[MeO-PIVE]-DOG. These lipopolymers were hydrolyzed under acidic conditions (pH 3.5 or 4.5) at rates that were dependent on the electron donating or withdrawing character of the α-phenyl vinyl ether substituent, while remaining stable at pH 7.4. Blending of these compounds with 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) in a 10:90 mPEG-PIVE-Lipid:DOPE ratio produced stable liposomes at neutral pH; however, acidification of the solution led to dePEGylation and release of the liposomal cargo in a manner that correlated with the PIVE proton affinity. Specifically, we observed 70% calcein release within 12 h from mPEG-[MeO-PIVE]-DOG-containing liposomes at pH 4.5, whereas only 22% calcein release was observed from mPEG-[F-PIVE]-DOG:DOPE liposomes over this same time scale and pH. These results indicate that dePEGylation following acidification is a triggering mechanism that can be rationally designed and controlled through the appropriate selection of PIVE moieties.
Relationship between Glasgow Coma Scale and functional outcome

The Glasgow Coma Scale (GCS) is routinely used in the acute care setting after traumatic brain injury (TBI) to guide decisions in triage, based on its ability to predict morbidity and mortality. Although the GCS has been previously demonstrated to predict mortality, efficacy in prediction of functional outcome has not been established. The purpose of this study was to assess the value of the acute GCS in predicting functional outcome in survivors of TBI. This study used the Multicenter National Institute on Disability and Rehabilitation Research TBI Model Systems database of 501 patients who had received acute medical care and inpatient rehabilitation within a coordinated neurotrauma program for treatment of TBI. Initial and lowest 24 hr GCS scores were correlated with the following outcome measures: the Disability Rating Scale (DRS), Rancho Los Amigos Levels of Cognitive Functioning Scale (LCFS), and cognitive and motor components of the Functional Independence Measure (FIM(SM)-COG and FIM(SM)-M). Outcome data were collected at admission to and discharge from the inpatient TBI rehabilitation unit. Correlation analysis revealed only modest, but statistically significant, relationships between initial and lowest GCS scores and outcome variables. Initial and lowest GCS score comparison with outcome demonstrated the following correlation coefficients: admission DRS, -0.25 and -0.28; discharge DRS, -0.24 and -0.24; admission LCFS, 0.31 and 0.33; discharge LCFS, 0.27 and 0.25; admission FIM-COG, 0.36 and 0.37; discharge FIM-COG, 0.23 and 0.23; admission FIM-M, 0.31 and 0.31; discharge FIM-M, 0.25 and 0.21. The GCS as a single variable may have limited value as a predictor of functional outcome.
The “Hidden” Trade of Metals in the United States

Summary The transport of ore and refined metals into and from countries has long been quantified, both because of its financial implications and because of the relative ease of tracking those flows. This information says little, however, about the net trade of metal in all its forms, particularly “semiproducts,” such as sheet and wire, and metal in traded products (MTP). A comprehensive analysis for the United States for copper, lead, zinc, chromium, and silver, in which all trade flows are included, demonstrates that MTP flows can often be a large factor in determining a country's import/export dependence, accounting for between 13% (zinc) and 57% (silver) of traded metal in all forms. A methodology was created to calculate the end user net import reliance, which is the net import of metal contained in ore, concentrate, refined forms, and semi-manufactured and finished products, plus any releases of metal from government or producer stocks, as a function of the flow of metal into end use by consumers. For all five metals, this calculation showed a higher reliance on imports than calculations that solely examine ore, concentrate, and refined metals. This suggests that the metal contained in semi-manufactured and finished products increases U.S. material import vulnerability. However, the in-use stocks of these metals contained in products may serve as a potential resource, serving to mitigate this vulnerability. Graphical representations of metal trade in all forms by geographical origin and destination are provided to characterize the nature of the trade and provide information that would be useful in characterizing U.S. import vulnerability.
Tool use in insect foraging by the chimpanzees of Ngogo, Kibale National Park, Uganda

Chimpanzee tool use for resource acquisition has been reported at numerous research sites. The chimpanzees of the Kibale Forest, western Uganda, have not previously been observed to use tools in foraging for insects. Here I report the first observation of tool use by the chimpanzees of the Ngogo community of Kibale National Park, Uganda, in insect foraging. Three adult females, one adolescent male, and one juvenile male were observed making and using tools to probe into a fallen dead tree to collect insect and wood pieces. I discuss the importance of this observation, and the behavioral similarities with chimpanzees from other sites.
Regulatory Requirements for Analytical Method Validation—A Case Study for Impurity Analysis

Current compliance regulations propose evaluation of various parameters required for analytical method validation. This paper presents the application of these guidelines for the analysis of impuri...
The optical conversion of F centers to M centers in KCl with repetitive light pulses

Abstract The optical conversion of F centers to M centers in KCl by 1 μ sec light pulses has been studied as a function of repetition rate, temperature, pulse intensity, and F center density. The initial rate of growth after a delay period increases with decreasing repetition rate while the maximum M band yield increases with increasing repetition rate, for both KCl-K. and Co-60 irradiated samples. The results obtained with irradiated crystals follow a kinetics model based on the combination of an anion vacancy with a nearby F ' center, in competition with thermal and optical ionization of the F ' center. It is proposed that the electronic motion during the delay period and the first stage of M center formation takes place via tunneling, while the later stages of aggregation in which bulk processes control involves the combination of anion vacancies with F centers or M centers. The relationship of this work to steady illumination measurements is discussed.
Aggregation, disaggregation, and the challenge of crossing levels of resolution when designing and connecting models

Virtual reality will sometimes require consistent simulated information at different levels of resolution. It will also require connecting models coherently that were designed independently. Basic concepts of variable-resolution modeling (VRM) are introduced, and a design approach involving hierarchical model processes and objects is described. Even in attempting to connect existing models, this approach can clarify the ideal, after which one can make integrated model adaptations rather than fixing connection problems sequentially. Experiments to improve the methods used in developing phenomenologically subtle variable-resolution models are described. How a mathematical analysis shed considerable light on a long-standing debate within the military modeling community is also described. An experiment with cross-organizational model comparisons that revealed subtle aggregation problems and may have been a prototype for what should be routine open discussion of models in circumstances where results can be reproduced or contradicted is discussed. >
Genome-wide discovery of transcriptional modules from DNA sequence and gene expression.

In this paper, we describe an approach for understanding transcriptional regulation from both gene expression and promoter sequence data. We aim to identify transcriptional modules—sets of genes that are co-regulated in a set of experiments, through a common motif profile. Using the EM algorithm, our approach refines both the module assignment and the motif profile so as to best explain the expression data as a function of transcriptional motifs. It also dynamically adds and deletes motifs, as required to provide a genome-wide explanation of the expression data. We evaluate the method on two Saccharomyces cerevisiae gene expression data sets, showing that our approach is better than a standard one at recovering known motifs and at generating biologically coherent modules. We also combine our results with binding localization data to obtain regulatory relationships with known transcription factors, and show that many of the inferred relationships have support in the literature.
COLLAGEN FIBER ORGANIZATION IS RELATED TO MECHANICAL PROPERTIES AND REMODELING IN EQUINE BONE. A COMPARSION OF TWO METHODS

We studied birefringence as an indicator of collagen fiber orientation in the diaphysis of the equine third metacarpal bone. We had previously shown that tissue from the lateral cortex of this bone is stronger monotonically, but less fatigue resistant, than tissue from the medial and dorsal regions. To learn whether collagen fiber orientation might play a role in this regional specialization, we tested three hypotheses using the same specimens: (1) collagen fiber orientation is regionally dependent; (2) remodeling changes collagen fiber orientation; (3) longitudinal collagen fibers correlate positively with modulus and monotonic bending strength and negatively with flexural fatigue life. Beams (N = 36) cut parallel to the long axes of six pairs of bones had been tested to determine elastic modulus (N = 36), and fatigue life (N= 24) or monotonic strength (N = 12) in four-point bending. Subsequently, histologic cross-sections were prepared, and porosity, active remodeling and past remodeling were quantified. Birefringence was measured as an indicator of transverse collagen orientation using plane-polarized light (PPL), and again using circularly polarized light (CPL). The CPL measurement was less variable than the PPL measurement. Both birefringence measures indicated that collagen was more longitudinally oriented in the lateral cortex than in the other two cortices. Longitudinally disposed collagen correlated with greater modulus and monotonic strength, but did not correlate with fatigue life. Remodeling was associated with more transverse collagen. Neither measure of birefringence was significantly correlated with porosity. It was concluded that, in the equine cannon bone, longitudinal collage fiber orientation is regionally variable, contributes to increased modulus and strength but not fatigue life, and is reduced by osteonal remodeling.
A Game Theoretic Analysis of the Republic of China's Emerging Electoral System

Despite differences in history, culture, and stages of political development, the same theoretical constructs used to study American and European political processes can be used to understand the Republic of China's evolving electoral institutions and processes. The particular theoretical constructs upon which we focus are game theory and its application to electoral politics, spatial models of party competition. After reviewing the core results of spatial analysis - that electoral systems dominated by a single issue occasion stable and convergent party platforms and that systems with multiple salient issues occasion instability - we examine the types of issues that opposition parties are most likely to use in challenging KMT rule. Based on this discussion we argue that the ROC ought to be especially sensitive to Riker's conclusion that evolving democracies should devote special attention to developing institutional structures such as bicameralism and staggered terms of office for legislators that avoid the populist ideal of direct democracy. Theoretical results reveal the fragility of the idea of a popular will, so that populist institutions designed to achieve it can foster electoral instability. We use a recent result about multi-candidate elections to argue that the form of electoral competition and the forces operating to produce factionalism within parties are functions of the extent to which voters perceive electoral competition in terms of individual candidate characteristics versus party labels. To the extent that voters evaluate candidates on the basis of their party label, the parties will tend to converge on issues; whereas, to the extent that voters focus on the specific characteristics of candidates and their policy pronouncements, the candidates will diverge on issues. Finally, we examine the circumstances under which the nature of the issues that concern an electorate determines the form of competition in democracies characterized by a single dominant party.
From Magnons to Solitons

This article concerns magnetism in nonmetallic solids. The analogy between magnons and phonons is established. Then, the exact 1- and 2-magnon spectra of ferromagnets are obtained, with bound states and scattering states being analyzed separately. The many-magnon states are obtained in a low-density approximation, and the effects of surfaces assessed.
Two‐dimensional analysis of a dust explosion

Peak pressures and propagation velocities for dust explosions have for many years been studied as a function of particle concentration. There are, however, no multidimensional models in the literature which can be used to compute local pressures and impulses needed to access the potential damage caused by detonation. A two-dimensional two-phase hydrodynamic computer model has been developed in this study to predict pressure propagation in dust explosions. Two cases of detonation of dispersed powders injected into a rectangular cavity are analyzed.
Towards commoditized real-time spectrum monitoring

We are facing an increasingly difficult challenge in spectrum management: how to perform real-time spectrum monitoring with strong coverage of deployed regions. Today's spectrum measurements are carried out by government employees driving around with specialized hardware that is usually bulky and expensive, making the task of gathering real-time, large-scale spectrum monitoring data extremely difficult and cost prohibitive. In this paper, we propose a solution to the spectrum monitoring problem by leveraging the power of the masses, i.e. millions of wireless users, using low-cost, commoditized spectrum monitoring hardware. We envision an ecosystem where crowdsourced smartphone users perform automated and continuous spectrum measurements using their mobile devices, and report the results to a monitoring agency in real-time. We perform an initial feasibility study to verify the efficacy of our mobile monitoring platform compared to that of conventional monitoring devices like USRP GNU radios. Results indicate that commoditized real-time spectrum monitoring is indeed feasible in the near future. We conclude by presenting a set of open challenges and potential directions for follow-up research.
Uncertain Property Rights and the Coase Theorem

The Coase theorem states that, in the absence of transaction costs, the assignment of property rights does not affect resource allocation, and the allocation is Pareto optimal. The theorem also implies that the order in which parties settle in a given location does not affect resource allocation either. This article argues that Pareto optimality is not attained in a class of prevalent cases involving uncertain rights, risk aversion, and resource divisibility. Resolution of the uncertainty results in a Pareto improvement for all parties and in a different allocation of resources if wealth effects are significant. Further, the article argues that the order in which parties settle in a given location may affect resource allocation.
An adaptive partial state-feedback controller for RLED robot manipulators

An adaptive partial state-feedback controller is designed for rigid-link electrically driven (RLED) robot manipulators. The controller is based on structural knowledge of the electromechanical dynamics of the RLED robot and measurements of link position and electrical winding current in each of the brushed DC link actuators. The proposed controller is designed to adapt for parametric uncertainty in the electromechanical dynamics while utilizing a dynamic filter to generate link velocity tracking error information. The controller, adaptation laws, and the pseudovelocity filter are designed via a Lyapunov-like approach, the benefit of which is that at the end of the design procedure the controller can be mathematically shown to produce semiglobal asymptotic link position tracking. The basic design approach can be extended to many types of multiphase motors.
Specificity of autoantibodies for recombinant 60–kd and 52–kd ro autoantigens

Objective. To compare patterns of Ro autoantigen recognition in primary Sjogren's syndrome (SS) and systemic lupus erythematosus (SLE). Methods. Sera were tested by enzyme–linked immunosorbent assay (ELISA) and immunoprecipitation for reactivity with recombinant human 60–kd and 52–kd Ro proteins. Results. SLE and primary SS sera exhibited similar patterns of reactivity with the recombinant 52–kd protein. However, a greater proportion of sera from primary SS patients than from SLE patients did not react with recombinant 60–kd protein in ELISA yet precipitated its translation product in solution–phase assays. Conclusion. Disease state can influence recognition of the recombinant 60–kd Ro antigen.
Study shows insufficient decrease in wound complications with sutured versus stapled skin closure in gastrointestinal operations

Commentary on: Tsujinaka T, Yamamoto K, Fujita J, et al. Subcuticular sutures versus staples for skin closure after open gastrointestinal surgery: a phase 3, multicentre, open-label, randomised controlled trial. Lancet 2013;382:1105–12.[OpenUrl][1][CrossRef][2][PubMed][3][Web of Science][4] Postoperative wound complications can occur in 9–26% of gastrointestinal operations.1–3 Skin closure with subcuticular sutures in clean operations, such as caesarean sections, are associated with decreased wound complications and increased patient satisfaction when compared with skin closure using staples.4 ,5 Whether these results are applicable to clean–contaminated operations is unknown. Tsujinaka and colleagues examined the incidence of wound complications after open gastrointestinal operations in patients undergoing skin closure with subcuticular sutures versus staples. This … [1]: {openurl}?query=rft.jtitle%253DLancet%26rft.volume%253D382%26rft.spage%253D1105%26rft_id%253Dinfo%253Adoi%252F10.1016%252FS0140-6736%252813%252961780-8%26rft_id%253Dinfo%253Apmid%252F24075050%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [2]: /lookup/external-ref?access_num=10.1016/S0140-6736(13)61780-8&link_type=DOI [3]: /lookup/external-ref?access_num=24075050&link_type=MED&atom=%2Febmed%2F19%2F3%2F100.atom [4]: /lookup/external-ref?access_num=000325208100026&link_type=ISI
Clinical characteristics of RA patients with secondary SS and association with joint damage

Objectives. Secondary SS (sSS) is a common extra-articular manifestation of RA. There are conflicting data regarding the association of sSS with worse joint damage. This study aims to characterize sSS patients in an RA cohort and study the association between sSS and joint damage. Methods. We conducted a cross-sectional study of RA patients with ≥1 year of follow-up at a large academic centre. Subjects with co-morbid diseases that can also result in sicca symptoms were excluded from the analysis. Subjects were considered to have sSS if they were reported as having sSS by their rheumatologist at recruitment into the cohort and had the diagnosis confirmed by chart review. The primary outcome was Sharp score using bilateral hand radiographs at recruitment. We constructed a linear regression model to determine the association of sSS status and Sharp score adjusted by age, gender, disease duration and ACPA and RF status. Results. We studied 829 RA subjects, mean age 57 years, 83% female, mean RA duration 13 years, 74% seropositive; 85 subjects (10.3%) had sSS. We observed a female predominance (95.3%), longer mean disease duration (16.9 years) and higher frequency of RF or ACPA positive among patients with sSS and RA. Having sSS at baseline was associated with higher Sharp scores (P = 0.03), independent of age, gender, RA disease duration and seropositive disease. Conclusion. In our RA cohort, RA subjects with sSS had worse joint damage, suggesting that sSS is a marker of more aggressive disease.
Behavior Therapy in the Classroom: A Case Report.

Abstract This article describes the development, procedures, and outcome of a behavior modification program on a preschool child enrolled in Head Start. The program used reciprocal inhibition techniques and shaping procedures to treat a five-year old Negro girl with a bathroom phobia. Individual sessions in the classroom, while the other children were on the playground, utilized sequential presentation of fear associated cues in the presence of preferred toys and candy. During regular class routines the teacher established body contact through hand holding, in the bathroom, to allay the fear. No fear combined with positive individual use of the bathroom was seen at the termination of the program. A three-month follow-up indicated short term stability of the new positive bathroom behavior. Discussion centers upon the therapeutic effectiveness of such a program and its workability in a school setting.
Effects of large herbivores and fire on the regeneration of Acacia erioloba woodlands in Chobe National Park, Botswana

Acacia erioloba woodlands provide important forage and shade for wildlife in northern Botswana. Mortality of mature trees caused by browsing elephants has been well documented but the lack of regeneration of new trees has received little attention. Annual growth of new shoots and changes in height were measured to determine the influence of elephants and small ungulate browsers, rainfall and fire on the growth and survival of established A. erioloba seedlings from 1995 to 1997 in the Savuti area of Chobe National Park. All above-ground vegetation was removed from 40% of established seedlings in 1995 and 28% in 1997 by browsing elephants, and the mean height of remaining seedlings decreased from >550 mm to <300 mm. When seedlings browsed by kudu, impala and steenbok but not elephants are considered, mean seedling height increased <50 mm per year, even though mean new shoot growth remaining at the end of the dry season was 100–200 mm. Fires burned portions of the study area in 1993 and 1997, killing above-ground vegetation, but most established A. erioloba seedlings survived, producing coppice growth from roots. While elephants and fire caused the greatest reduction in established seedling height and number, small browsers suppressed growth, keeping seedlings vulnerable to fire and delaying growth to reproductive maturity. Resume Les forets d'Acacia erioloba procurent une nourriture et des abris importants pour la faune au nord du Botswana. On connait bien la mortalite des grands arbres due aux elephants mais on n'a accorde que peu d' attention au manque de regeneration de nouveaux arbres. On a mesure la croissance annuelle des jeunes pousses et le changement de hauteur pour determiner l'influence des elephants et des petits ongules, des chutes de pluies et des feux sur la croissance et la survie des semis connus d' A. erioloba, de 1995 a 1997 dans la zone de Savuti au Parc National de Chobe. Toute la vegetation au-dessus du sol a ete supprimee sur 40% des semis connus en 1995, et 28% en 1997 par le broutage des elephants, et la hauteur moyenne des plants restants a baisse de > 550 mm a < 300 mm. Lorsqu'on considere les pousses broutees par les koudous, les impalas et les steenbocks, mais pas par les elephants, la hauteur moyenne des jeunes pousses augmentait de moins de 50 mm par an meme si la croissance moyenne des nouvelles pousses subsistant a la fin de la saison seche etait de 100 a 200 mm. Les feux ont brule des portions de la zone etudiee en 1993 et en 1997, tuant toute la vegetation au-dessus du sol, mais les pousses d' A. erioloba les mieux situees ont survecu, produisant de nouveaux taillis au depart des racines. Alors que les elephants et les feux causaient les plus fortes reductions de la hauteur et du nombre des pousses etablies, les petits ruminants en supprimaient la croissance, ce qui les laissait vulnerables aux feux et retardait la croissance jusqu'a la maturite.
Residual-effected homogeneous charge compression ignition with delayed intake-valve closing at elevated compression ratio

AbstractResidual-effected homogeneous charge compression ignition (HCCI) was investigated using a single-cylinder research engine equipped with fully-flexible variable valve actuation. Operation at elevated compression ratios was explored to determine its effect on efficiency. Results showed that efficiency is decreased significantly by advanced phasing owing to increased thermal losses. However, if combustion phasing is held fixed, elevated compression ratio operation showed little effect on efficiency. Further experiments explored the use of IVC time as a control parameter at the elevated compression ratio. Tests were conducted to determine if an efficiency benefit could be realized from increasing the compression ratio and delaying IVC to increase the extent of expansion relative to compression. No significant change in efficiency was observed, although variation in IVC timing offered significant control authority. Delayed IVC was used in conjunction with variable IVO to control independently load and ...
Multiprocessor implementation of real-time DSP algorithms

In this paper, we consider multiprocessor implementation of real-time recursive digital signal processing algorithms. The objective is to devise a periodic schedule, and a fully static task assignment scheme to meet the desired throughput rate while minimizing the number of processors. Toward this goal, we propose a notion called cutoff time. We prove that the minimum-processor schedule can be found within a finite time interval bounded by the cutoff time. As such the complexity of the scheduling algorithm and the allocation algorithm can be significantly reduced. Next, taking advantage of the cutoff time, we derive efficient heuristic algorithms which promise better performance and less computation complexity compared to other existing algorithms. Extensive benchmark examples are tested which yield most encouraging results. >
Inhibition of creatine and phosphocreatine accumulation in skeletal muscle and heart

Abstract A series of creatine analogues was tested for ability to inhibit 14C-creatine accumulation in vivo and for ability to serve as substrates for creatine kinase in vitro. The most potent inhibitors of accumulation were 1-carboxymethyl-2-imino-hexahydropyrimidine, N-methylamidino-N-methylglycine, β-guanidinopropionate, and DL-β-guanidinobutyrate. The first two compounds are known to be inactive as substrates for creatine kinase, and DL-β-guanidinobutyrate was shown to be inactive in the present experiments, producing a Vmax less than 0.01% of that produced by creatine. The latter compound and β-guanidinopropionate were also found to be ineffective as inhibitors of creatine kinase in vitro. The best substrates for creatine kinase were N-ethyl-N-amidinoglycine and guanidinoacetate; these two compounds were inefficient as inhibitors of 14C-creatine accumulation. Moreover, adding a methyl group to β-guanidinopropionate to form N-methyl-N-amidino-β-alanine eliminated the compound's ability to inhibit 14C-creatine accumulation but had little effect on its ability to serve as a substrate for creatine kinase. Thus, we found no evidence that creatine kinase mediates creatine transport. In feeding trials with rats given DL-β-guanidinobutyric acid as 2% or 6% of their diet for 1 mo, this compound accumulated to concentrations of 14 μmole/g wet weight in skeletal muscle and of 4 μmole/g wet weight in heart. Simultaneously, in skeletal muscle there was a depletion of phosphocreatine to 50%, and of ATP to 80%, of control values. The total creatine content (creatine + phosphocreatine) of the heart also decreased, going from 12.8 to 2.8 μmole/g wet weight. Animals fed DL-β-guanidinobutyric acid should be suitable for studies of the long-term effects of creatine and phosphocreatine depletion in skeletal muscle and heart.