cssi/SciSciGPT-SciSciNet huggingface dataset:
Leukotrienes mediate 5-hydroxytryptamine-induced plasma extravasation in the rat knee joint via CysLT-type receptors.

Objective and design:The aim of this study was to investigate whether leukotrienes synthesized by 5-lipoxygenase (5-LO) and acting via leukotriene (LT) receptors contribute to 5-hydroxytryptamine (5-HT)-induced knee joint plasma extravasation (PE). Materials and methods:Knee joints of rats under anesthesia were perfused with 5-HT and synovial vascular Evans Blue dye leakage was measured spectrophotometrically. A series of 5-LO inhibitors and LT receptor antagonists were investigated for their ability to inhibit 5-HT-induced synovial PE. Results:Inhibitors of 5-LO (NDGA and REV 5901) significantly attenuated 5-HT-induced plasma extravasation. MK 571, LY 171883, BAY u9773 (CysLT receptor antagonists) and REV 5901 (a CysLT receptor antagonist and a 5-LO inhibitor) were equally effective in inhibiting 5-HT-induced PE, indicating that leukotrienes mediate 5-HT-induced PE via CysLT receptors. In contrast, antagonists selective for LTB4 receptors (BLT1 and BLT2 receptors) failed to reduce 5-HT-induced PE. Conclusions:These results demonstrate that leukotrienes, specifically cysteinyl-leukotrienes contribute to synovial plasma extravasation and suggest that leukotrienes act downstream of 5-HT in the inflammatory cascade.
The Selection Theory of Persisting Party Advantages in Russia: More Evidence and Implications

Abstract Rona-Tas and Guseva (2001) present four criticisms of the “selection theory” explaining why former Communist Party members do better in post-Soviet Russia. None of their criticisms constitute definitive evidence against the selection theory. However, they raise reasonable doubts regarding the timing of the survey and the specification of the model used to empirically confirm the theory in my original article (Gerber, 2000a). These doubts are laid to rest based on a range of empirical evidence, including a new analysis of survey data collected in 2000. The selection theory remains the most compelling and empirically substantiated explanation of the success of former Communist Party members in post-Soviet Russia. The theory points to previously overlooked similarities in stratification processes in state socialist and capitalist societies.
Angiography of atrioventricular canal defects.

Abstract The axial angiograms of 20 patients with an atrioventricular (A-V) canal defect were carefully examined and compared with anatomic observations made at operation. A common A-V valve was present in 15 patients and two separate valves in 5. The atrial septal defect, the anatomy of the ventricular septum and the morphology and functional status of the A-V valves were well demonstrated. There was consistent angiographic deformation of the normally straight contour extending from the noncoronary aortic cusp to the crux cordis observed in the four chamber and elongated right anterior oblique projections of the left ventricular angiogram of each patient. This deformity is caused by the deficiency or absence of the A-V septum and is the best angiographic sign of the malformation. The differentiation of two separate valves from a common A-V valve was uniformly made. When a common A-V valve was present, three of the five leaflets were usually identified but distinction of the free floating from the tethered anterior leaflet was not always possible. It is concluded that axial techniques provide more complete angiographic definition of the anatomic abnormalities of A-V canal defects than are demonstrated from frontal and lateral views.
Changes in the management of children with intersex conditions.

Three broad recommendations have been made for the management of children with intersex conditions: halt all infant cosmetic genital surgery until evidence-based guidelines are available; conduct further research on the necessity of such surgery; and practice complete honesty with parents and patients. The authors discuss whether clinical practice has changed in response to these recommendations.
Photoencapsulation of osteoblasts in injectable RGD-modified PEG hydrogels for bone tissue engineering

Poly(ethylene glycol) (PEG) hydrogels were investigated as encapsulation matrices for osteoblasts to assess their applicability in promoting bone tissue engineering. Non-adhesive hydrogels were modified with adhesive Arg-Gly-Asp (RGD) peptide sequences to facilitate the adhesion, spreading, and, consequently, cytoskeletal organization of rat calvarial osteoblasts. When attached to hydrogel surfaces, the density and area of osteoblasts attached were dramatically different between modified and unmodified hydrogels. A concentration dependence of RGD groups was observed, with increased osteoblast attachment and spreading with higher RGD concentrations, and cytoskeleton organization was seen with only the highest peptide density. A majority of the osteoblasts survived the photoencapsulation process when gels were formed with 10% macromer, but a decrease in osteoblast viability of approximately 25% and 38% was seen after 1 day of in vitro culture when the macromer concentration was increased to 20 and 30wt%, respectively. There was no statistical difference in cell viability when peptides were added to the network. Finally, mineral deposits were seen in all hydrogels after 4 weeks of in vitro culture, but a significant increase in mineralization was observed upon introduction of adhesive peptides throughout the network.
Reporting Empirical Research on Adolescence: Reflections on the Appeal of Coherence, Purpose and Responsibility

The study of adolescence has come of age. Many successful journals now provide researchers with a wide variety of reasonable options for contributing to our understanding of adolescents and their place in society. This article explores these options and offers suggestions to prospective authors, especially those who expect to publish in the Journal of Youth and Adolescence (JYA). This article briefly overviews the scope and audiences of the field's leading journals to emphasize the need to select appropriate publishing outlets. The discussion demonstrates how that selection helps determine the eventual success of submitted manuscripts and influences manuscript effectiveness. The analysis then suggests ways to avoid common errors and to write effective, publishable manuscripts that have a sense of purpose and coherence. The article ends by emphasizing the need to write responsibly, in a way that tempers scientific endeavors with a sense of responsibility to adolescents, their lived environments, broader society and the study of adolescence.
Stress and worry: examining intolerance of uncertainty's moderating effect

Intolerance of uncertainty (IU), or the way an individual perceives, interprets, and reacts to uncertainty in life, has been frequently investigated in relation to anxiety and worry. While a substantial body of research suggests that individual differences in IU foster stress and anxiety, IU's involvement as a potential moderator in the relation between stressful events and worry has only recently been investigated. Therefore, the present study examined the moderating effect of IU on the relation between daily hassles and worry as well as major life events and worry in a sample of 1092 young adults. Results revealed that IU showed a significant moderation effect in the relation between daily stress and worry. More specifically, when the two factors were examined individually only inhibitory IU served as a moderator between daily stress and worry. While major life events significantly predicted worry, no moderation effect was found for this relation. These findings highlight the need to better understand the mechanisms through which IU impacts worry and contributes to anxiety.
Anthropomorphic dummy neck modeling and injury considerations

This study investigates the modeling of the Hybrid III dummy head and neck system and its response under impulsive loading. Two neck models were proposed, one rigid, one flexible; both give satisfactory head kinematics upon comparing to minisled test results. The flexible neck model provides a more detailed understanding of the Hybrid III neck structure behavior. It indicates that the Hybrid III neck has a torque response similar to a human neck but has higher shear response. During flexion whiplash, the torque at the occipital condyle reverses its direction at about 25 ms after impact. Since concussion may be related to the head angular acceleration, which reaches its peak value in the first 25 ms, it might be necessary to extend the existing human torque-rotation corridor to include the neck response in this region. For flexion whiplash impact, simulation results indicated that the neck injury threshold is reached before exceeding the head injury threshold as the impact velocity is increased.
Gauge and gravitational anomalies in two dimensions.

Gauge and gravitational anomalies are studied in two dimensions. In the gauge-anomaly case, we obtain the solution of the anomaly equation (the Wess-Zumino term) with only gauge fields, without auxiliary fields. Then we show, up to the second nontrivial order, that this solution agrees with the explicit Feynman-diagram calculation. In the gravitational-anomaly case we show, up to the second nontrivial order, that the anomaly obtained by the differential geometric method agrees with the explicit Feynman-diagram calculation.
Expression of the helix–loop–helix protein inhibitor of DNA binding-1 (ID-1) is activated by all-trans retinoic acid in normal human keratinocytes

The ID (inhibitor of differentiation or DNA binding) helix-loop-helix proteins are important mediators of cellular differentiation and proliferation in a variety of cell types through regulation of gene expression. Overexpression of the ID proteins in normal human keratinocytes results in extension of culture lifespan, indicating that these proteins are important for epidermal differentiation. Our hypothesis is that the ID proteins are targets of the retinoic acid signaling pathway in keratinocytes. Retinoids, vitamin A analogues, are powerful regulators of cell growth and differentiation and are widely used in the prevention and treatment of a variety of cancers in humans. Furthermore, retinoic acid is necessary for the maintenance of epithelial differentiation and demonstrates an inhibitory action on skin carcinogenesis. We examined the effect of all-trans retinoic acid on expression of ID-1, -2, -3, and -4 in normal human keratinocytes and found that exposure of these cells to all-trans retinoic acid causes an increase in both ID-1 and ID-3 gene expression. Furthermore, our data show that this increase is mediated by increased transcription involving several cis-acting elements in the distal portion of the promoter, including a CREB-binding site, an Egr1 element, and an YY1 site. These data demonstrate that the ID proteins are direct targets of the retinoic acid signaling pathway. Given the importance of the ID proteins to epidermal differentiation, these results suggest that IDs may be mediating some of the effects of all-trans retinoic acid in normal human keratinocytes.
Quantitative Microdetermination of Enzymes in Sweat Gland: V. Ouabain-Sensitive Sodium-Potassium Activated Adenosinetriphosphatase

Extract: The excessive concentration of sodium chloride in sweat in cystic fibrosis may be due to failure of a ‘sodium pump’ mechanism. In view of a possible relationship between electrolyte transport and ouabain sensitive ATPase, determination of this enzyme activity was undertaken in isolated sweat gland tissue from cystic fibrosis and control subjects. In each case, determinations were made with optimal Na+, K+ and Mg++ in the substrate mixture, with or without ouabain. With activities expressed as moles phosphate liberated per kg dry sweat gland tissue per hour, seven cystic fibrosis patients gave a mean ouabain sensitive ATPase activity of 2.0 ± 1.1 (SD). Seven controls gave 2.9 ± 1.6. This difference was not significant statistically (t = 1.1). Speculation: Contrary to what might have been suspected from reported results on a relationship between ouabain sensitive ATPase and sodium transport in various sites, namely, crab nerve tissue, avian salt gland, human and sheep erythrocytes and various other tissues, the present study involving skin biopsies from cystic fibrosis patients and controls fails to show this enzyme to be deficient in relation to the defect in sodium transport in the sweat gland in cystic fibrosis.
Changes in extracellular potassium activity during neocortical propagated seizures.

Abstract Direct measurements of extracellular potassium concentration [(K + )o] using a potassium-sensitive microelectrode were carried out in the pericruciate cortex of cats during propagated seizures initiated by repetitive stimulation of the surface of the opposite homotopic neocortex. (K + )o increases during either subthreshold stimulus trains or ictal episodes were dependent on cortical depth and distance from the homotopic point. Seizures could be classified by typical increases in (K + )o: 0.5± 0.06m m /1 with minor and 5.9 ± 0.8 m m /1 above the steady state value with major seizures. The upper limit for (K + )o during ictal events was 10.2 m m /1. A postictal undershoot of (K + )o below steady state was observed. The elevation of (K + )o to a critical value during stimulation was associated with a “threshold” for the initiation of propagated seizures. That value was 0.5 m m /1 for minor seizures and 1.8 m m /1 for major seizures. Both minor and major seizures were found to act as “all or none” phenomena of variable morphology. The role of (K + )o in the modulation of CNS activity and the pathogenesis of ictal phenomena is discussed.
Cyclic amp-independent relaxation of depolarized rat ileal smooth muscle by isoproterenol

Abstract Isoproterenol brings about a rapid transient relaxation of depolarized ileal smooth muscle as well as a longer lasting decline in tension. Only the latter effect is mimicked by dibutyryl cyclic AMP or by phosphodiesterase inhibitors. Beta adrenergic blocking agents cause a rapid transient contraction in preparations relaxed by isoproterenol but not in preparations relaxed by the other agents, and this effect persists when influx of Ca 2+ from the extracellular space is prevented. The transient component of the isoproterenol-induced relaxation is therefore attributed to sequestration of Ca 2+ at intracellular sites, and the contraction which follows the subsequent addition of beta blocking agents is due to release of Ca 2+ from these sites.
Detecting instabilities of cardiac rhythm

Diminished beat-to-beat variations in cardiac cycle lengths (CLs) are associated with poor prognosis after acute myocardial infarction and in patients with heart failure. Short-long-short sequences of cardiac cycles, or ultra-short rhythm instabilities, precede initiation of ventricular tachyarrhythmias in some patients. However, little is known about clinical or prognostic significance of abrupt short-term instabilities in CL (AICL) that occur minutes to hours before the event, in part because appropriate analytical methods are lacking. Although various techniques have been used to analyze CL changes, methods for analysis of AICL are limited. We compared performance of time domain, spectral, nonlinear, and pattern recognition techniques with respect to the detection and quantification of AICL. Because of high intra- and inter-subject variability of CL, pattern recognition techniques compared favorably to other studied methods. In continuous ambulatory ECG recordings, AICL occurred hours before spontaneous initiation of sustained atrial and ventricular arrhythmias in different patient populations. AICL were also found prior to the onset of spontaneous ventricular arrhythmias in a mouse model of congestive heart failure. To quantify AICL, we used the number of unstable orthogonal projection coefficients; this number gradually increased hours before the event. Removal of ectopic beats reduced but did not eliminate AICL. To illustrate potential physiological effects and temporal evolution of AICL, we used a simple, continuous, two-dimensional model of cardiac tissue governed by the Morris-Lecar equations. Computer simulations in this model showed that AICL may lead to gradual accumulation of spatial irregularities of the propagation wavefront giving rise to the initiation of reentry. Time-frequency analysis of the most significant eigenvectors of cardiac rhythm in subjects undergoing head-up tilt showed that AICL could indicate instabilities and unsuccessful adaptation of autonomic nervous system activity to physiological stimuli.
Workload dependent evaluation of thin-film thermoelectric devices for on-chip cooling and energy harvesting

The recent advances in thin-film thermoelectric (TE) materials have created opportunities for on-chip cooling and energy-harvesting with heat-fluxes >100W/cm2. However, it remains unclear how effective these materials are in the context of realistic microprocessor floorplan and workloads. Moreover, these TE materials suffer from contact parasitics that can significantly impact their performance. To evaluate the workload dependent performance of on-chip TE devices, we developed a hierarchical simulation methodology that connects an architectural simulator and a power estimation tool with a thermal simulator capable of simulating TE devices. The well-known HotSpot thermal simulator is modified to incorporate TE equations along with contact parasitics in the TE module. SimpleScalar and McPAT were used to generate the runtime power of different functional units in an Out-of-Order processor across the SPEC2000 workloads. The power-map generated by McPAT is used by our TE enhanced HotSpot simulator to evaluate the cooling and harvesting capabilities of on-chip TE modules. Our results indicate that it is possible to obtain 11°C peak cooling at the hot-spots, or harvest upto 85mW of power from the hot-spots. We also show that on-chip TE devices can aid in boosting the clock frequency of the processor from 1200MHz to 1600MHz under iso-temperature comparison with the no-TE case. This framework also allows for the rapid design space exploration of TE module's material/physical parameters and the optimum placement options for the TE module on the chip floorplan.
A cohesive zone model for fatigue crack growth in quasibrittle materials

Abstract A cohesive zone model for fatigue crack initiation and growth in quasibrittle materials is proposed in the present paper. While bulk material is modeled to be linearly elastic, the softening material in the cohesive zone and cracks are modeled to be internal singular surfaces in the elastic body. The interactions of the singular surfaces are described in a cohesive force law and a Coulomb-type friction law if in contact. The cohesive zone material is modeled to accumulate damage not only along the damage locus but also along an unloading path underneath it, enabling a simulation of fatigue damage and crack growth without the ad hoc imposition of a law of growth rate within the cohesive zone model. The maximum principal stress criterion is used to advance a tip of the cohesive zone in the direction of the maximum principal stress when it reaches the critical value of material strength. The physical crack tip is grown as a natural process of debonding of the cohesive zone under cyclic loading, which, in contrast, may be subcritical with energy dissipation less than the material toughness under static loading. The boundary value problem formulated for fatigue crack growth incorporating the cohesive zone model is nonlinear due to the history dependence of the cohesive zone, and is solved efficiently using the iterative single-domain dual-boundary-element method of successive over-relaxation. It is demonstrated through examples that the present model is capable of predicting fatigue crack initiation as well as growth in a unified way. It is also shown that the cohesive zone model is more advantageous and flexible in handling fatigue cracks under arbitrary loading than the classical singularity-based fracture mechanics approach.
Prenatally diagnosed giant omphaloceles: short‐ and long‐term outcomes

Objectives To review prenatal findings, short- and long-term outcomes of giant omphaloceles (GO) managed at a single institution (1996–2001). Methods Prenatal findings and early postnatal outcomes were retrospectively reviewed. Clinical short- and long-term outcomes were analyzed in eight and five children respectively. Parents and physicians of the children were surveyed by written questionnaires about the children's subsequent health issues. (IRB 2002-2-2683). Results Seventeen pregnancies with GO were identified: Eight fetuses were live born, four ended in (terminations), two died in utero and three were lost to follow-up. Live-born fetuses had prenatal ascites, extreme levocardia and were delivered by cesarean section at a mean of 37 weeks' gestation with a mean birth weight of 2903 g. All neonates required intubation. Two infants (2/8) died within one year. Four of the six survivors had respiratory insufficiency with a mean ventilation time of 76 days. Respiratory and feeding problems complicated the early neonatal course. Long-term follow-up was available for five patients (mean age of 33.2 months). Asthma, recurrent pulmonary infections, feeding problems, gastroesophageal reflux and failure to thrive were the major problems. Conclusions Respiratory and feeding problems were the most common neonatal and long-term medical management issues. Parents need to be counseled prenatally about the probability of multiple surgeries and long hospitalization following birth. Copyright © 2004 John Wiley & Sons, Ltd.
Markov decision process (MDP) framework for optimizing software on mobile phones

We present a framework based on Markov decision process to optimize software on mobile phones. Unlike previous approaches in literature that focus on energy optimization while meeting a specific task-related time constraint, we model the desired talk-time as an explicit user given parameter and formulate the optimization of resources such as battery-life on a mobile phone as a decision processes that maximizes a user specified application specific reward or utility metric while meeting the talk-time constraint. We propose efficient techniques to solve the optimization problem based on dynamic programming and illustrate how it can be used in the context of realistic applications such as WiFi radio power optimization and email synchronization. We present a design methodology to use the proposed technique and experimental results using the Android platform from Google running on the HTC mobile phone.
A correlation between glucose concentration, accumulation of ethanol, and germ tube biogenesis in the dimorphic moldMucor rouxii

The conversion of yeastlike cells to hyphae inMucor rouxii, a dimorphic mold, was altered by increasing the glucose concentration in the growth medium. High glucose concentrations (i) inhibited germ tube biogenesis, (ii) reduced hyphal branching, and (iii) effected a significant increase in the rate of ethanol accumulation during an air-induced shift in vegetative cell type. The inhibition of germ tube biogenesis was most pronounced when 1 and 10% glucose was added to the growth medium. Yeastlike cells in 10% glucose lacked germ tubes after 4 hours of aerobic growth while those in 0 and 0.01% glucose had undergone the transformation to highly branched hyphae. In addition, cultures with 10% glucose failed to produce branches throughout the course of the experiment. The effect of glucose on morphology was even more pronounced when the size of the initial inoculum was increased. It was also observed that the amount of ethanol produced by the organism increased as a function of glucose concentration in the medium. This increase, which was shown to be independent of any biomass increase, was most significant when 10% glucose was used in the growth medium. The accumulation of ethanol was enhanced even more by increasing the size of the initial inoculum.
Age-Related Changes in Rat Corneal Epithelial Nerve Density

PURPOSE To determine the effect of aging on corneal epithelial nerve density in an animal model. METHODS Corneal whole mounts from rats aged 6, 12, 18, and 24 months were stained immunohistochemically with antisera against the pan-neuronal marker neurotubulin. Epithelial nerve terminals and subbasal nerves in standardized 1-mm(2) central and peripheral zones from each cornea were drawn using a drawing tube attached to a light microscope. Images were scanned, and nerve densities were calculated as the percentage of each 1-mm(2) area occupied by nerves. The diameters of subbasal nerves in 6- and 24-month old animals were measured. Subbasal nerve vortices were analyzed qualitatively with reference to location, morphologic appearance, and directionality. RESULTS Epithelial nerve terminal density decreased by approximately 50% between 6 and 24 months. The rate of decline was roughly linear and similar in both central and peripheral cornea. In contrast, subbasal nerve density increased by more than 50% between 6 and 24 months in both central and peripheral cornea. The mean diameter of corneal subbasal nerves decreased approximately 30% (0.384 microm vs. 0.271 microm) between 6 and 24 months. The morphologic appearance and directionality of the subbasal nerve vortex demonstrated considerable interanimal variability and did not correlate with age. CONCLUSIONS Rat corneal nerve terminal density decreases, but corneal subbasal nerve density increases, as a function of age. The age-related loss of nerve terminal density seen in the rat cornea is in keeping with the decreased corneal sensitivity reported in elderly humans and may contribute to the pathogenesis of dry eye disease in aged persons.
Piezoelectric ceramic implants: in vivo results

The suitability of barium titanate (BaTiO3) ceramic for direct substitution of hard tissues was evaluated using both electrically stimulated (piezoelectric) and inactive (nonpolarized) test implants. Textured cylindrical specimens, half of them made piezoelectric by polarization in a high electric field, were implanted into the cortex of the midshaft region of the femora of dogs for various periods of time. Interfacial healing and bio-compatibility of the implant material were studied using mechanical, microradiographical, and histological techniques. Our results indicate that barium titanate ceramic shows a very high degree of biocompatibility as evidenced by the absence of inflammatory or foreign body reactions at the implant-tissue interface. Furthermore, the material and its surface porosity allowed a high degree of bone ingrowth as evidenced by microradiography and a high degree of interfacial tensile strength. No difference was found between the piezoelectric and the electrically neutral implant-tissue interfaces. Possible reasons for this are discussed. The excellent mechanical properties of barium titanate, its superior biocompatibility, and the ability of bone to form a strong mechanical interfacial bond with it, makes this material a new candidate for further tests for hard tissue replacement.
Competitive modes as reliable predictors of chaos versus hyperchaos and as geometric mappings accurately delimiting attractors

We consider real quadratic dynamics in the context of competitive modes, which allows us to view chaotic systems as ensembles of competing nonlinear oscillators. We find that the standard competitive mode conditions may in fact be interpreted and employed slightly more generally than has usually been done in recent investigations, with negative values of the squared mode frequencies in fact being admissible in chaotic regimes, provided that the competition among them persists. This is somewhat reminiscent of, but of course not directly correlated to, “stretching (along unstable manifolds) and folding (due to local volume dissipation)” on chaotic attractors. This new feature allows for the system variables to grow exponentially during time intervals when mode frequencies are imaginary and comparable, while oscillating at instants when the frequencies are real and locked in or entrained. In addition to an application of the method to chaotic attractors, we consider systems exhibiting hyperchaos and conclude that the latter exhibit three competitive modes rather than two for the former. Finally, in a novel twist, we reinterpret the components of the Competitive Modes analysis as simple geometric criteria to map out the spatial location and extent, as well as the rough general shape, of the system attractor for any parameter sets corresponding to chaos. The accuracy of this mapping adds further evidence to the growing body of recent work on the correctness and usefulness of competitive modes. In fact, it may be considered a strong “a posteriori” validation of the Competitive Modes conjectures and analysis.
New divergent dynamics in the isotropic to nematic phase transition of liquid crystals measured with 2D IR vibrational echo spectroscopy

The isotropic phase of nematogenic liquid crystals has nanometer length scale domains with pseudonematic ordering. As the isotropic to nematic phase transition temperature (TNI) is approached from above, the orientational correlation length, ξ, of the pseudonematic domains grows as (T - T(*))(-1/2), where T(*) is 0.5-1 K below TNI. The orientational relaxation, which is a collective property of the pseudonematic domains, was measured with optical heterodyne detected-optical Kerr effect (OHD-OKE). The orientational relaxation obeys Landau-de Gennes theory, as has been shown previously. To examine the environmental evolution experienced by molecules in the pseudonematic domains, two-dimensional infrared (2D IR) vibrational echo experiments on the CN stretching mode of the non-perturbative vibrational probes 4-pentyl-4(')-selenocyanobiphenyl (5SeCB) and 4-pentyl-4(')-thiocyanobiphenyl (5SCB) in the nematogen 4-cyano-4(')-pentylbiphenyl (5CB) were performed. The 2D IR experiments measure spectral diffusion, which is caused by structural fluctuations that couple to the CN vibrational frequency. Temperature dependent studies were performed just above TNI, where the correlation length of pseudonematic domains is large and changing rapidly with temperature. These studies were compared to 2D IR experiments on 4-pentylbiphenyl (5B), a non-mesogenic liquid that is very similar in structure to 5CB. The time constants of spectral diffusion in 5CB and 5B are practically identical at temperatures ≥5 K above TNI. As the temperature is lowered, spectral diffusion in 5B slows gradually. However, the time constants for spectral diffusion in 5CB slow dramatically and diverge as T(*) is approached. This divergence has temperature dependence proportional to (T - T(*))(-1/2), precisely the same as seen for the correlation length of pseudonematic domains, but different from the observed orientational relaxation times, which are given by the Landau-de Gennes theory. The data and previous results show that spectral diffusion in 5CB has no contributions from orientational relaxation, and the structural dynamics responsible for the spectral diffusion are likely a result of density fluctuations. The results suggest that the correlation length of the density fluctuations is diverging with the same temperature dependence as the pseudonematic domain correlation length, ξ. The isotropic-nematic phase transition in liquid crystals is described in the context of the slowing of orientational relaxation associated with divergent growth of the orientational correlation length. The results presented here show that there is another divergent dynamical process, likely associated with density fluctuations.
Dagwood: a system for manipulating polynomials given by straight-line programs

We discuss the design, implementation, and benchmarking of a system that can manipulate symbolic expressions represented by their straight-line computations. Our system is capable of performing rational arithmetic on, evaluating, differentiating, taking greatest common divisors of, and factoring polynomials in straight-line format. The straight-line results can also be converted to standard, sparse format. We show by example that our system can handle problems for which conventional methods lead to excessive intermediate expression swell.
Electro-optic measurements of dye/polymer systems

Electro-optical (EO) coefficients are determined for two dye/polymer guest-host systems as a function of the electric field, temperature, and concentration. Above the glass transition temperature, the EO coefficient of methyl nitroaniline in poly(methyl methacrylate) is shown to be due to the Kerr effect. The order parameter induced by the poling field is deduced from the electro-optical coefficient. Interpretation of the order parameter in terms of the Langevin functions alone does not agree with the experimental results.
Adolescent Use of Selected Areas in the Parental Dwelling

Using a self-reporting inventory, 614 adolescents in two age categories, 12–14 years and 16–18 years, responded concerning their use of the living room, a second living area if the home included one, and the bedroom. The objective was to determine the effects on space use of six independent variables: age, sex, family size, birth order, the presence of single or plural living areas in the home, and whether bedroom space was shared or used solely by the adolescent. Living room use was defined as having two components, activities performed and frequency. Significant differences on both components were found when comparisons were made between those with one living room and those with plural living areas, and when family size exceeded five mem bers. Frequency of living room use increased significantly when the respondents shared a bedroom. If the home had a single living area, girls performed a significantly greater number of activities in the space than boys, and younger adolescents spent a significantly greater amount of time in the area than older adolescents. No significant differences were found in the use of the second living area. Whether the respondent had sole use of the bedroom or shared the space, girls were found to perform a significantly greater number of activities in the room than boys. Analysis of the findings suggests an interrelationship between living room and bedroom use by adolescents that may need to be addressed as families assess housing needs and wants.
Responses of evaporite mineralogy to inflow water sources and climate during the past 100 k.y. in Death Valley, California

The mineralogy of cored sediments from Badwater Basin, Death Valley, California, provides information on water inflow sources and climate over the past 100 k.y. Abundant glauberite (Na 2 SO 4 ċ CaSO 4 ) and gypsum (CaSO 4 ċ 2H 2 O), and relatively small amounts of calcite are associated with mudflat deposits from dry periods from 0 to 10 ka and 60 to 100 ka. In contrast, scarce CaSO 4 -bearing minerals but relatively abundant calcite are associated with halite and mud layers from 10 to 60 ka, including the 25 ka wet period when Death Valley contained a perennial lake (10 to 35 ka). Different mixing ratios of inflow waters between wet and dry periods are interpreted to be responsible for the relationship between mineral assemblages and climate. Modern Death Valley, representative of dry periods, is characterized by Na-Cl-SO 4 brines, produced by mixing two basic types of inflow waters: (1) Na-HCO 3 –rich and Na-Cl-SO 4 -HCO 3 –rich meteoric waters from the Amargosa River, springs, and ground waters from northern and central Death Valley; and (2) Na-Ca-Cl-rich springs and ground waters from southern Death Valley, possibly related to volcanism, hydrothermal activity, and a 15-km-deep magma body. During dry periods, relatively abundant Ca-rich spring inflow removes HCO 3 as calcite during the early stages of brine evolution. Further evaporative concentration produces gypsum and glauberite from the remaining Ca. During wetter periods, increased discharge of meteoric HCO 3 –rich Amargosa River water and basin-margin spring waters removes most Ca from the brine via precipitation of calcite, and, with low calcium concentrations, CaSO 4 -minerals are not abundantly formed during further evaporative concentration. Such Ca-poor, Na-Cl-SO 4 -rich brines precipitate thenardite (Na 2 SO 4 ) during later stages of brine evolution.
Generation of fine hydromagmatic ash by growth and disintegration of glassy rinds

[1] The deposits of mafic hydromagmatic eruptions are more fine grained and variable in vesicularity than dry magmatic deposits. Blocky, equant shapes of many hydromagmatic clasts also contrast with droplet, thread, and bubble wall morphology of dry magmatic fragments. Small (<∼180 μm), blocky hydromagmatic pyroclasts have traditionally been interpreted to result from discrete vapor explosions, although such explosions tend to occur only under certain conditions. This paper considers a process of hydromagmatic ash formation that involves repeated growth and disintegration of glassy rinds on pyroclast surfaces as they deform within turbulent flows. This process, termed “turbulent shedding”, may occur during the expansion phase of vapor explosions or during turbulent but nonexplosive mixing of magma with water, steam, or water sprays. The occurrence of turbulent shedding and the resulting fragment sizes depend on the timescale for rind growth and the timescale between disturbances that remove or disintegrate glassy rinds. Turbulent shedding is directly observable in some small littoral jets at Kilauea. Calculations suggest that, in the presence of liquid water or water sprays, glassy rinds having a thickness of microns to millimeters should form in milliseconds to seconds. This is similar to the timescale between turbulent velocity fluctuations that can shred lava globules and remove such rinds. The fraction of a deposit consisting of fine ash should increase with the duration of this process: Large-scale Surtseyan jets generate hundreds or thousands of shedding events; bubble bursts or tephra jets at Kilauea's coast may produce only a few.
Effects of Heroin/Cocaine Combinations in Rats Trained to Discriminate Heroin or Cocaine from Saline

The effects of heroin and cocaine administered alone or in combination were examined in rats trained to discriminate either heroin (0.56 mg/kg i.p.; n = 6) or cocaine (5.6 mg/kg i.p.; n = 6) from saline. Heroin (0.032-1.8 mg/kg) substituted completely for the heroin training stimulus in all six heroin-trained rats, but failed to substitute for cocaine in any of the cocaine-trained rats. Cocaine (0.1-32 mg/kg) substituted completely for the cocaine training stimulus in all six cocaine-trained rats, and substituted for heroin in two of six heroin-trained rats. The opioid antagonist naltrexone (0.01-1.0 mg/kg) antagonized the discriminative stimulus effects of heroin, but naltrexone at doses up to 10 mg/kg had no effect on the discriminative stimulus effects of cocaine. The dopamine receptor antagonist flupenthixol (0.032-0.56 mg/kg) attenuated the discriminative stimulus effects of heroin and completely blocked the discriminative stimulus effects of cocaine. When heroin-cocaine combinations were administered to the heroin-trained rats, cocaine (1-5.6 mg/kg) did not significantly alter the mean heroin dose-effect curve. Similarly, in the cocaine-trained rats, heroin (0.1-0.56 mg/kg) did not significantly alter the mean cocaine dose-effect curve. These results suggest that combinations of heroin and cocaine usually produce discriminative stimulus effects similar to either heroin or cocaine alone.
Terrestrial gypsum from Alaska and Greenland in glacially influenced marine sediments

Abstract Gypsum grains were identified in Miocene–Pleistocene sediment cores from two deep-water ODP sites, Site 918 off the SE Greenland margin and Site 887 in the Gulf of Alaska, and in Holocene sediment cores from shallow-water localities in Disenchantment Bay and Muir Inlet in southern Alaska. Although initial morphologic and textural observations suggested a complex system in which the gypsum may have had more than one origin, quantitative sulfur isotope analyses of the gypsum provide evidence of its detrital nature. δ34S values in gypsum from southern Alaska range between +0.0 and +7.1‰. Gypsum has δ34S values between −27.1 and −27.5‰ in the Gulf of Alaska and values between −28.5 and +0.2‰ off the SE Greenland margin. All of these isotopic signatures are too highly depleted in δ34S to have precipitated from seawater, present or past. In addition there is no significant change in δ34S values for gypsum crystals with differing physical characteristics (abraded vs. unabraded) from the same stratigraphic horizon, suggesting all the gypsum is detrital regardless of the degree of abrasion. The isotopic and physical evidence, in combination with the onshore geology the environmental setting, and site characteristics of the gypsum-bearing marine localities, lead us to propose that the ultimate source of the gypsum is precipitation from freeze-induced terrestrial sediment or soil brines. Furthermore the combined evidence suggests that the subsequent occurrence of gypsum in glacimarine sediments results from ice-rafting (by icebergs or sea ice) of the frozen regolith and/or, in the proximal glacimarine setting of southern Alaska, very rapid burial via turbidity currents.
Effect of plasma gases on OH radical generation in atmospheric pressure microwave plasma jet using UV cavity ring down spectroscopy

OH radical plays an important role in biomedical, material, and combustion processing as well as in many other applications. Quantification of OH radicals in atmospheric pressure microwave plasma jets can be useful for understanding of OH formation mechanism and plasma generation. As reported previously, OH radicals exist in the far downstream (distance / plasma column length > 3) of an atmospheric pressure argon plasma jet. So far, we have confirmed that the similar phenomenon also exits in helium plasma jets, N 2 or O 2 mixed with argon plasma jets, and N2 or O 2 mixed with helium plasma jets. Here, the plasma column, which was generated using a microwave plasma source of 2.45 GHz, was typically of 3 mm long. Effects of addition of nitrogen and oxygen gases to argon in different mixing ratios, such as Ar: N 2 = 56:1, Ar: N 2 = 24:1, Ar: N 2 = 13:1 and Ar: O 2 = 27:1, were studied in detail using CRDS, OES and visual imaging. With addition of N 2 in argon plasma, a plume tail appears in the plasma jet column while addition of O 2 makes the plasma column unstable and more like a plume instead of a jet shape. Spectral simulations of emission spectra observed under various circumstances and temperature measurements clearly indicate that the gas temperature of Ar + N 2 plasma is higher than that of Ar + O 2 plasma. Absolute number densities of OH (v" = 0, J" = 3.5) along the plasma jet column were measured in these plasma jets. Dependence of absolute number density of OH on plasma power and gas flow-rate (variation in mixing ratios of N 2 and O 2 ) were also studied. The similar studies were carried out for addition of N 2 and O 2 in helium plasma jets with the mixing ratios of He: N 2 = 44:1 and He: O 2 = 41:1, respectively. As helium plasma jets are more stable, addition of N 2 or O 2 changes the jets into an unstable jet and a plume-like plasma, respectively. The results suggest that the addition of N 2 and O 2 in argon and helium plasma jets is helpful for OH radical generation but also makes the plasmas less stable.
Multi-view tracking of articulated human motion in silhouette and pose manifolds

This paper presents a multi-view articulated human motion tracking framework using particle filter with manifold learning through Gaussian process latent variable model. The dimensionality of the input image observation and joint angles are reduced using Gaussian process models to improve the tracking efficiency. The forward and backward mappings between the two low dimensional spaces are then obtained using relevance vector machine and Batesian mixture of experts (BME). Improved sampling schemes and auto-initialization are obtained using BME.Without using a 3D body model, effective likelihood evaluation is obtained through RVM using images from multiple views. Tracking results obtained using real videos with complex dance movement show the efficacy of the proposed approach.
Emerging Pharmacotherapies for COPD

The mainstay of current drug therapy is long-acting bronchodilators; several longer acting inhaled β2-agonists and muscarinic antagonists (and combinations) are now in development. No treatments have so far been shown to reduce the progression or suppress the inflammation of COPD. With better understanding of the inflammatory and destructive processes in the pathophysiology of COPD, several new targets have been identified. Several mediator antagonists tested in COPD patients have so far been disappointing, but CXC receptor 2 antagonists that block pulmonary neutrophil and monocyte recruitment may be more promising. Broad-spectrum antiinflammatory drugs, including inhibitors of the enzymes phosphodiesterase 4, p38 mitogen-activated protein kinase, nuclear factor-κB, and phosphoinositide-3-kinase-γ, may be more effective, but the side effects will be a major limitation so that inhaled delivery may be necessary. Perhaps the most promising approach is the reversal of corticosteroid resistance through increasing histone deacetylase-2 activity. This might be achieved by theophylline-like drugs, more effective antioxidants, and nonantibiotic macrolide agents.
Identification of Survival Motor Neuron as a Transcriptional Activator-Binding Protein

Spinal muscular atrophy (SMA) is an inherited neuro-muscular disease characterized by specific degeneration of spinal cord anterior horn cells and subsequent muscle atrophy. Survival motor neuron ( SMN ), located on chromosome 5q13, is the SMA-determining gene. In the nucleus, SMN is present in large foci called gems, the function of which is not yet known, while cytoplasmic SMN has been implicated in snRNP biogenesis. In SMA patients, SMN protein levels and the number of gems generally correlate with disease severity, suggesting a critical nuclear function for SMN. In a screen for proteins associated with the nuclear transcription activator 'E2' of papillomavirus, two independent SMN cDNAs were isolated. The E2 and SMN proteins were found to associate specifically in vitro and in vivo. Expression of SMN enhanced E2-dependent transcriptional activation, and patient-derived SMN missense mutations reduced E2 gene expression. Our results demonstrate that SMN interacts with a nuclear transcription factor and imply that SMN may serve a role in regulating gene expression. These observations suggest that SMA may in part result from abnormal gene expression and that E2 may influence viral gene expression through SMN interaction.
β-Turn secondary structure and melanocortin ligands

The melanocortin pathway has emerged during this past decade as an important target area for the discovery and development of therapeutic agents related to obesity and type 2 diabetes. This peptide-G-protein coupled receptor (GPCR) pathway has evolved from peptide-based ligands to small molecules possessing a variety of different molecular scaffolds. Herein, we summarize the originating hypothesis of the importance of the reverse β-turn secondary structure for agonist ligand potency at the melanocortin receptors and how that information was utilized for the discovery of small molecules based upon this type of turn structure.