cssi/SciSciGPT-SciSciNet huggingface dataset:
Promising Practice of Technology Integration in Math and Science Instruction: A Case of California Charter High School

This study was conducted to examine the promising practice of using technology in teaching math and science in a charter high school in California. The research employed an in-depth qualitative case study method. The main participants were principals, lead teachers, teachers, and support staff. Interviews, observations, and archival documents were the main data collection tools. The study found that the practice of using technology in teaching by the school, Center for Advanced Research and Technology (CART), has lead to positive educational outcomes. These include increased student achievement in standardized test scores, increased motivation, growth in mean GPA, less behavior problems from students, and improved school attendance by students. Implications for policy and practice were discussed.
Functional and therapeutic significance of Akt deregulation in malignant melanoma.

Identification of specific genes or signaling pathways involved in development of melanoma could lead to new therapies that target and correct these defects. Recent studies have revealed deregulation of the Akt signaling pathway occuring in 43–67% of melanomas. Akt kinase family members, Akt1/PKBα, Akt2/PKBβ and Akt3/PKBγ, share extensive structural similarity and perform common as well as unique functions within cells. The Akt signaling cascade initiates at the cell surface when growth factors or other extracellular stimuli activate phosphoinositide 3-kinase (PI3K). Activated PI3K generates a lipid second messenger, phosphatidylinositol-3,4,5-trisphosphate (PIP3), causing translocation of Akt to the plasma membrane where it becomes phosphorylated and activated. The balance of cellular PIP3 is regulated primarily by a phosphatase called PTEN that reduces PIP3 levels thereby lowering Akt activity. In melanomas, decreased PTEN activity elevates PIP3 levels resulting in Akt activation. Active Akt then phosphorylates downstream cellular proteins that promote melanoma cell proliferation and survival. Recently, Akt3 was discovered to be the predominant isoform activated in sporadic melanomas. Levels of activity increased during melanoma progression with metastatic melanomas having the highest activity. Although mechanisms of Akt3 activation remain to be fully characterized, overexpression of Akt3 and decreased PTEN activity play important roles in this process. Targeted reduction of Akt3 activity decreased survival of melanoma tumor cells leading to inhibition of tumor development, which may be therapeutically effective for shrinking tumors in melanoma patients. This review surveys recent developments in Akt deregulation in melanoma and its potential as a selective therapeutic target in patients in the advanced stages of this disease.
Glucose control and cardiovascular outcomes: reorienting approach

Cardiovascular disease accounts for nearly 70% of morbidity and mortality in patients with diabetes mellitus. Strides made in diabetes care have indeed helped prevent or reduce the burden of microvascular complications in both type 1 and type 2 diabetes. However, the same cannot be said about macrovascular disease in diabetes. Several prospective trials so far have failed to provide conclusive evidence of the superiority of glycemic control in reducing macrovascular complications or death rates in people with advanced disease or those with long duration of diabetes. There are trends that suggest that benefits are restricted to those with lesser burden and shorter duration of disease. Furthermore, it is also suggested that benefits might accrue but it would take a longer time to manifest. Clinicians are faced with the challenge to decide how to triage patients for intensified care vs less intense care. This review focuses on evidence and attempts to provide a balanced view of the literature that has radically affected how physicians treat patients with macrovascular disease. It also takes cognizance of the fact that the natural course of the disease may be changing as well, possibly related to better overall awareness and possibly improved access to information about better individual healthcare. The review further takes note of some hard held notions about the pathobiology of the disease that must be interpreted with caution in light of new and emerging data. In light of recent developments ADA and EASD have taken step to provide some guidance to clinicians through a joint position statement. A lot more research would be required to figure out how best to manage macrovascular disease in diabetes mellitus. Glucocentric stance would need to be reconsidered, and attention paid to concurrent multifactorial interventions that seem to be effective in reducing vascular outcomes.
The elementary interaction force between a dislocation loop and the flux line lattice of a type II superconductor

Abstract The elementary interaction force f between prismatic dislocation loop and the flux line lattice due to both first- and second-order strain field interactions is computed. A new Fourier transform method for defects radially symmetric about the flux line direction is developed and used to compute the second-order interaction as well as to check the results of the first-order interaction calculated previously by the Peach-Koehler formula. Small interstitial loops are attracted to flux line cores by the first-order interaction and repelled by the second-order interaction whereas small vacancy loops are repelled by both interactions. For both interactions, the maximum interaction force f p of a loop much smaller than the flux line spacing a 0 increases with loop diameter D approximately as D 2. For larger loops f p increases less rapidly with D, goes through a maximum at D≈a 0/2 and rapidly decreases to zero at D≈a 0. For still larger D the sign of the interaction force is reversed (repulsive pins bec...
Critical issues in the treatment of anger

This article proposes that anger has received less attention in the behavior therapy literature than other emotional disorders. Little research exists to guide clinical practice on the effectiveness of interventions to treat anger. Suggestions are made for treating angry clients. These suggestions are presented as researchable hypotheses. It is proposed that angry clients often fail to establish a therapeutic alliance with their therapists. Failure to agree on the goal of changing their anger is the component of the alliance which is most problematic. Strategies to develop the therapeutic alliance with angry clients are proposed. Script theories of emotions are presented as an important tool for understanding clients' reluctance to change and in establishing the alliance with clients of different cultural backgrounds. The creation of new scripts that are acceptable to the client's cultural group is presented as one strategy to establish a therapeutic alliance. It is suggested that the use of exposure based treatment may be a promising treatment for anger.
Sequential Bayesian Prediction and Adaptive Sampling Algorithms for Mobile Sensor Networks

In this technical note, we formulate a fully Bayesian approach for spatio-temporal Gaussian process regression such that multifactorial effects of observations, measurement noise and prior distributions are all correctly incorporated in the predictive distribution. Using discrete prior probabilities and compactly supported kernels, we provide a way to design sequential Bayesian prediction algorithms in which exact predictive distributions can be computed in constant time as the number of observations increases. For a special case, a distributed implementation of sequential Bayesian prediction algorithms has been proposed for mobile sensor networks. An adaptive sampling strategy for mobile sensors, using the maximum a posteriori (MAP) estimation, has been proposed to minimize the prediction error variances. Simulation results illustrate the practical usefulness of the proposed theoretically-correct algorithms.
Human β-globin pre-mRNA synthesized in vitro is accurately spliced in xenopus oocyte nuclei

Abstract To study the mechanisms of RNA splicing we have synthesized β-globin mRNA precursors by in vitro transcription using a plasmid in which a human β-globin gene is fused to an efficient bacteriophage promoter. The structural requirements for accurate splicing of the in vitro synthesized pre-mRNAs were investigated by injection into Xenopus oocyte nuclei. We detect splicing only if the pre-mRNA is capped in vitro prior to injection; uncapped RNA is rapidly degraded. In addition, we find that in vitro synthesized pre-mRNAs that are not polyadenylated or lack a normal 3′ end are spliced following injection into oocytes. The observation that a purified pre-mRNA can be spliced in oocytes indicates that transcription and splicing are not obligatorily coupled. When an in vitro synthesized β-globin pre-mRNA containing a splice junction mutation is microinjected, the affected junction is not spliced, indicating that sequences necessary for accurate splicing in human cells are also necessary for splicing in oocytes.
Microscopic computed tomography imaging of the cerebral circulation in mice: Feasibility and pitfalls

This study evaluates the utility and practical limitations of microcomputerized X-ray tomography (CT) as a research tool for examination of the cerebral circulation in mice. Six micro CT angiograms of the circle of Willis (COW) from six mice were obtained by scanning whole head and brain specimen perfused with a radio-opaque silicone contrast agent. Two-dimensional volume rendered images were postprocessed from three-dimensional image datasets using a partially automated high-throughput model that generated 10 surface projections for each specimen. The image processing model employed a straightforward global thresholding and computerized component labeling software algorithm. Postprocessed images were analyzed and results correlated with microdissection. Micro CT demonstration of COW vessels and their branch anatomy was assessed. 71% of COW vessels were completely demonstrated, 26% were partially demonstrated, and 3% were not demonstrated. All cases of nondemonstration and most cases of partial demonstration resulted from scan coverage or postprocessing clip error. Thresholding effect caused pseudostenosis of 8% of COW vessels and accounted for a minority of partial demonstration cases. No imaging artifacts were caused by contrast extravasation or ineffective contrast perfusion. Volume averaging caused minor angioarchitectural distortion of 58% of COW vessels. Ninety-five percent of COW ≥50 μm and 52% of COW vessels <50 μm were correctly identified by micro CT. Micro CT of the murine COW using a high-throughput image processing model is feasible. Angioarchitectural distortion due to volume averaging and thresholding effect can occur and pathological findings should be confirmed. Synapse 62:557–565, 2008. © 2008 Wiley-Liss, Inc.
Operator-stable laws

Sharpe investigated the structure of full operator-stable measures μ on a vector group V and obtained decompositions, μ = μ1 ∗ μ2 and V = V1 ⊕ V2, in terms of the Gaussian component μ1 and the Poisson component μ2. The subspaces V1 and V2 are here identified in terms of an exponent B for μ. Sharpe also pointed out that the Levy measure M of μ is a mixture of Levy measures concentrated on single orbits of tB. Here, an explicit representation is obtained for M as such a mixture by constructing a measure on the unit sphere. Also, necessary and sufficient conditions are given that a Levy measure be the Levy measure of a full operator-stable measure. The final result deals with full Gaussian measures μ and establishes the connection between its covariance operator and the class of all exponents of μ.
Architecture design of reconfigurable pipelined datapaths

This paper examines reconfigurable pipelined datapaths (RaPiDs), a new architecture style for computation-intensive applications that bridges the cost/performance gap between general purpose and application specific architectures. RaPiDs can provide significantly higher performance than general purpose processors on a wide range of applications from the areas of video and signal processing, scientific computing and communications. Moreover, RaPiDs provide the flexibility that does not come with application-specific architectures. A RaPiD architecture is optimized for highly repetitive, computationally-intensive tasks. Very deep application-specific computation pipelines can be configured that deliver very high performance for a wide range of applications. RaPiDs achieve this using a coarse-grained reconfigurable architecture that mixes the appropriate amount of static configuration with dynamic control. We describe the fundamental features of a RaPiD architecture, including the linear array of functional units, a programmable segmented bus structure, and a programmable control architecture. In addition, we outline the floorplan of the architecture and provide timing data for the most critical paths. We conclude with performance numbers for several applications on an instance of a RaPiD architecture.
Gamete ripening and hormonal correlates in three strains of lake trout

Abstract In our 2-year laboratory study of hatchery-reared adult lake trout Salvelinus namaycush of the Seneca Lake, Marquette (Lake Superior Lean), and Jenny Lake strains, we compared gamete ripening times and changes in plasma concentrations of seven hormones. If interstrain differences in these traits were found, such differences might help explain the apparent failure of stocked fish of these strains to develop large, naturally reproducing populations in the Great Lakes. The complex temporal changes in plasma hormone levels that occur during sexual maturation in lake trout have not been previously described. We detected little evidence of temporal isolation that would prevent interbreeding among the three strains. Strain had no effect on ovulation date (OD) in either year. Strain did not affect spermiation onset date (SOD) in year 1 but did in year 2, when the mean SOD of Jenny Lake males was earlier than that of Seneca Lake males but not different from that of Marquette males. Hormonal data were norm...
Acute necrotising pancreatitis: a late and fatal complication of pancreaticoduodenal arterial embolisation

A 70-year-old man was diagnosed with a massive bleeding duodenal ulcer which was refractory to emergency endoscopic management. Angiogram of the coeliac and superior mesenteric arteries revealed bleeding from the superior and inferior pancreaticoduodenal arteries. Transcatheter arterial embolisation of superior and inferior pancreaticoduodenal arteries along with the gastroduodenal artery was performed. Two weeks later he developed severe necrotising pancreatitis of the pancreatic head probably due to ischaemia, which was managed conservatively. Three months later the patient experienced another episode of pancreatitis which progressed into multiorgan dysfunction and the patient passed away.
Cimetidine inhibits the formation of the reactive, toxic metabolite of isoniazid in rats but not in man

The hepatotoxicity of isoniazid in rats results from the metabolic activation of acetylhydrazine, a metabolite of isoniazid, by the cytochrome P450 monooxygenase system. Inhibition of the drugmetabolizing enzyme system with a compound suitable for clinical use such as cimetidine might therefore prevent liver injury in experimental animals and in patients on isoniazid without interfering with the antituberculous activity of the drug. To test this hypothesis, we studied the effect of cimetidine on acetylhydrazine-induced hepatocellular necrosis in rats and the formation of 14CO2 from [14C]acetylisoniazid, which provides an indirect assessment of the fraction of a dose of isoniazid metabolized via the toxifying pathway. Pretreatment of rats with 150 mg per kg of cimetidine significantly decreased the extent of hepatocellular necrosis produced by 100 mg per kg of aeetylhydrazine and the formation of 14CO2 from [14C]acetylisoniazid. In man, however, 300 mg of cimetidine administered every 6 hr did not decrease the formation of 14CO2 from [14C] acetylisoniazid administered concomitantly with 300 mg of isoniazid; similarly, cimetidine did not affect the urinary excretion of isoniazid, acetylisoniazid, acetylhydrazine and diacetylhydrazine. These data demonstrate that the mechanistic information obtained in animal models cannot be applied readily in clinical practice and that measurable inhibition of acetylhydrazine metabolism to prevent isoniazid liver injury does not occur after administration of therapeutic doses of cimetidine to patients.
Using Conventional Analysis in Parallel with Geographical Information Systems Techniques to Examine the Distribution of Brown Shrimp in the Mississippi Sound

Abstract A geographical information systems technique for visualizing spatial data was used in conjunction with standard analytical procedures to examine the size-specific distribution of brown shrimp Farfantepenaeus aztecus in nearshore nursery areas and open waters of the Mississippi Sound. Brown shrimp abundance was assessed during 2000, 2001, and 2002 by means of an otter trawl along 10 transects consisting of three stations each. The number of brown shrimp, together with the dissolved oxygen, temperature, and salinity values, were collected at each sampling station. A decreasing trend in salinity was observed from east to west. The highest salinities were measured in 2000. No temporal patterns in dissolved oxygen or temperature were apparent. Brown shrimp showed the highest abundances in western Mississippi Sound, an area adjoining the extensive marshes of St. Tammany and St. Bernard parishes in Louisiana. The average size of the brown shrimp in the western sound was smaller than that of the brown sh...
The Perceived Fairness of Layoff Practices1

Policy capturing was used to identify layoff practices having the greatest impact on the perceived fairness of layoffs. Full-time employees (N = 23) rated the fairness of 100 hypothetical layoffs incorporating each of 12 layoff practices reflecting different approaches to organizational justice. Managerial consistency in implementing layoffs, an unbiased layoff policy, and the size of severance packages had the strongest influence on fairness judgments. These results suggest that practices reflecting structural aspects of justice play the greatest role in layoff fairness perceptions, whereas practices consistent with social aspects of justice may be relatively less important.
Development of a Particle–Particle Hybrid Scheme to Simulate Multiscale Transitional Flows

In the present work, a new particle–particle hybrid method that combines the statistical ellipsoidal-statistical Bhatnagar–Gross–Krook and direct simulation Monte Carlo methods is developed. The switching criterion between the two methods is based on the deviation of the cumulative velocity distribution function from Maxwellian as measured by the Kolmogorov–Smirnov statistical test. Unlike other hybrid approaches that use switching criteria based on macroscopic properties, the selection of a particular particle method in a cell is determined by the local Kolmogorov–Smirnov parameter value with respect to a preset global switching criterion. A numerically efficient technique to compute the Kolmogorov–Smirnov parameter was developed to enable the efficient calculation of the degree of nonequilibrium. Two well-known fluid-flow problems, expanding argon flow through a nozzle and hypersonic flow over a blunt body, were studied. The Kolmogorov–Smirnov parameter is shown to demarcate the regions of nonequilibriu...
Physical factors affecting human blood viscosity

Abstract Human blood viscosity was measured under varying conditions to determine the influence of certain physical factors on this parameter. Normal human blood viscosity at an hematocrit of 36% was only one-half the blood viscosity noted when hematocrit was 53%. Whole blood viscosity determined at 37.5°C. was markedly less than whole blood viscosity of the same blood when determined at 25°C. Marked fluctuations in viscosity were noted when blood was allowed to remain in vitro for long periods of time prior to viscosity determinations.
Renal norepinephrine spillover during infusion of nonesterified fatty acids

Background Sympathetic activity and renal norepinephrine spillover are increased in obese individuals. We have reported that infusion of nonesterified fatty acids increases blood pressure in animals through stimulation of the sympathetic nervous system. Methods In this study, we assessed the effect of increasing circulating nonesterified fatty acids on systemic and renal norepinephrine kinetics in healthy adults by infusing fat emulsion and heparin for 4 h. 3H-norepinephrine was infused for 60 min before and again during the last hour of the fatty acid infusion to assess norepinephrine kinetics. Renal venous blood samples were obtained to calculate renal norepinephrine spillover. Results Nonesterified fatty acid levels increased threefold during the first hour and remained elevated throughout the study. Arterial and renal venous plasma norepinephrine levels fell by 15% and 20%, respectively, during the infusion (P < .05 for both). Kinetic analysis indicated that systemic release of norepinephrine into an extravascular compartment decreased from 11.6 ± 1.1 to 10.0 ± 1.3 nmol/min/m2 (P = .067) and renal venous norepinephrine spillover decreased from 454 ± 54 pmol/min (P = .055). Conclusions These results indicate that nonesterified fatty acids do not have a direct stimulating effect on whole-body or renal sympathetic activity. It is possible that increased plasma levels of fatty acids serve as a signal to decrease sympathetic tone during the fasting state.
Dual Role Relationships: What Makes Them so Problematic?.

The author argues that all dual role relationships, not only those involving sexual contact, may be ethically problematic. Three guidelines are offered to differentiate between relationships that have a high probability of leading to harm and those that do not. First, as the incompatibility of expectations increases between roles, so will the potential for harm. Second, as the obligations associated with different roles diverge, the potential for loss of objectivity and divided loyalties increases. Third, as the power and prestige between the professional's and consumer's roles increase, so does the potential for exploitation. Last, it is argued that, as the risks of harm increase, so should the ethical prohibitions about engaging in the relationship.
Stability of three-dimensional boundary layers

A theory is presented for the three-dimensional stability of boundary layers. Equations are derived for the evolution of a disturbance having a given frequency and originating at a given curve. These equations are used to determine the rays along which the disturbance energy propagates. It is shown that the results can be obtained by using the saddle-point method, or kinematic wave theory, or the method of multiple scales. Extension of the theory to the case of a wave packet is also presented.
Effect of intersolution interval, chlordiazepoxide, and amphetamine on anticipatory contrast

Previous experiments have shown that the intake of a 0.15% saccharin solution is suppressed if saccharin access is followed by access to 32 % sucrose in brief daily pairings. The present experiments found that: (1) the degree of suppression was not altered when no time elapsed between presentation of the two solutions each day (15 sec had been the minimum in previous experiments and was used as the control in this experiment); (2) the degree of suppression was not altered by chlordiazepoxide (6, 12, or 20 mg/kg), although the drug had large appetite-stimulating effects; (3) suppression was not influenced by amphetamine (0.25 or 0.50 mg/kg); and (4) contrast could be established or eliminated, even after extended training, by manipulating the sequences of solutions presented (saccharin-saccharin or saccharin-sucrose). The results were interpreted in terms of a contrast effect based on the learned anticipation of a preferred substance. The chlordiazepoxide data suggest that this contrast is different from successive negative contrast, and the intersolution interval data suggest that the occurrence of contrast rather than a reinforcement effect is not due to a time gap between presentations of the two solutions.
Individual-based chaos: extensions of the discrete logistic model.

Simple models of density-dependent population growth such as the discrete logistic map provide powerful demonstrations of complex population dynamics. Yet it is unclear whether the dynamics observed in such idealized systems would be present, under realistic conditions, in the context of demographic stochasticity, which is well known to exist in finite natural populations. Here, using a set of simple, individual-based models (IBM's) and their population-level iterative map counterparts, we computationally investigate the contribution of demographic stochasticity to density-dependent population dynamics in a simple model of seed production and recruitment. Notably, for a sufficiently large lattice, even in the presence of demographic stochasticity, many of the qualitative features of these idealized maps – including bifurcations – are still present. Demographic stochasticity and the constraints imposed by a finite lattice size appear to produce mixed dynamics that are partially stochastic, yet qualitatively similar to the deterministic models. The mechanistic assumptions and lattice sizes required to generate these dynamics cast doubt on whether they might be observable in annual plant populations. Nevertheless, we cannot rule out the theoretical possibility that such dynamics might be observable in ecological communities having similar mechanistic properties.
Rapid isolation of animal mitochondrial DNA in a small fixed-angle rotor at ultrahigh speed.

In recent years, mitochondrial DNA (mtDNA) sequence analysis has become a powerful tool for the investigation of the evolutionary and population biology of various animal species (Wilson et al., 1985). Most such studies have relied on physical purification of mtDNA, typically by ultracentrifugation in cesium chloride gradients. Thorough descriptions of such methods are given by Lansman et al. (1981) and Wright et al. (1983). Practical concerns over the expensive instrumentation and extensive time required by such methods have been expressed by several workers (e.g., Grill et al., 1983; Powell and Zufiiga, 1983). Several of our colleagues have expressed doubt that purified mtDNA samples can be generated in a reasonable time in numbers sufficient to perform large-scale population studies. We describe here an ultracentrifugal procedure that yields homogeneous mitochondrial DNA from as many as i0 samples in as little as 10 hr. The procedure uses a relatively inexpensive tabletop ultracentrifuge and relies on a self-forming cesium chloride gradient generated in a small fixed-angle rotor that operates at a speed of 100,000 rpm and a relative centrifugal force of 436,000g.
The spawning reflex response of the killifish, Fundulus heteroclitus: Isotocin is relatively inactive in comparison with arginine vasotocin

The Fundulus spawning reflex activity of the teleostean neurohypophysial peptides, arginine vasotocin (AVT) and isotocin (IT), was assayed by criteria specified in earlier investigations. One Fundulus unit is contained in 47–62.5 ng/g of AVT, but a 10-fold larger dose of IT is required, 480–790 ng/g. The effective dose of AVT is similar to that reported for arginine vasopressin (AVP), 53 ng/g. Oxytocin (OT) requires a somewhat larger dose, ca. 100 ng/g, but it is nevertheless more active than the corresponding teleostean peptide, IT. Vasopressor activity was considered as a possible common denominator in the spawning reflex activity of the basic peptides, AVT and AVP, but negative results are reported for other teleostean vasoactive agents: catecholamines, angiotensin II and an extract of Gillichthys urophysis. The response is specific to neurohypophysial peptides, but the long latency and pharmacological nature of the effective dose present as yet unresolved problems.
Endoscopic Correction of Vesicoureteral Reflux Secondary to Posterior Urethral Valves

AbstractPurpose: We review our experience with children with high grade vesicoureteral reflux secondary to posterior urethral valves treated endoscopically with subureteral polytetrafluoroethylene (Teflon) injection.Materials and Methods: Between 1985 and 1994, 54 infants and children were diagnosed with posterior urethral valves of whom 38 (70 percent) had vesicoureteral reflux. In 9 patients reflux resolved after valve ablation. Seven patients underwent nephroureterectomy for nonfunctioning kidneys and in 2 reflux was treated with continuous chemoprophylaxis. The remaining 20 patients underwent an antireflux procedure, including reimplantation of the ureters in 5 and subureteral polytetrafluoroethylene injection in 15. Of the 15 patients who underwent injection 6 had unilateral and 9 had bilateral vesicoureteral reflux. According to the international classification reflux was grade IV in 6 ureters and grade V in 18. Patient age at injection ranged from 8 months to 6 years (mean 2.2 years).Results: Reflu...
Acoustic pulse propagation in an urban environment using a three-dimensional numerical simulation.

Acoustic pulse propagation in outdoor urban environments is a physically complex phenomenon due to the predominance of reflection, diffraction, and scattering. This is especially true in non-line-of-sight cases, where edge diffraction and high-order scattering are major components of acoustic energy transport. Past work by Albert and Liu [J. Acoust. Soc. Am. 127, 1335–1346 (2010)] has shown that many of these effects can be captured using a two-dimensional finite-difference time-domain method, which was compared to the measured data recorded in an army training village. In this paper, a full three-dimensional analysis of acoustic pulse propagation is presented. This analysis is enabled by the adaptive rectangular decomposition method by Raghuvanshi, Narain and Lin [IEEE Trans. Visual. Comput. Graphics 15, 789–801 (2009)], which models sound propagation in the same scene in three dimensions. The simulation is run at a much higher usable bandwidth (nearly 450 Hz) and took only a few minutes on a desktop computer. It is shown that a three-dimensional solution provides better agreement with measured data than two-dimensional modeling, especially in cases where propagation over rooftops is important. In general, the predicted acoustic responses match well with measured results for the source/sensor locations.
Astrophysics: A tight duo in a trio of black holes

Tight pairs of supermassive black holes are expected to emit gravitational waves that could give astronomers a new way to explore the cosmos. One relatively tight pair has been discovered within a rare triple system. See Letter p.57 The discovery of a triple supermassive black hole system in a distant (redshift z = 0.39) galaxy provides a rare opportunity to observe what may be the result of galactic mergers. In the four known triple black hole systems, the smallest distance between a pair of black holes is 2.4 kiloparsecs, but the newly discovered triple system includes a 'tight pair' separated by around 140 parsecs. The authors show that the presence of the tight pair is imprinted onto the properties of the large-scale radio jets generated by the black holes, providing a useful way of searching for other tight pairs without the need for extremely high-resolution observations. Six candidate galaxies were surveyed in this study, a 'hit rate' that suggests that tight pairs are more common than was thought. Close-pair binaries are useful targets for gravitational wave studies, so the development of an efficient way of finding them, and the prospect of there being more of them, should stimulate interest in work on predicting the strength of gravitational waves and assist in their eventual detection.
Manipulation of 3D Cluster Size and Geometry by Release from 2D Micropatterns

A novel method to control three-dimensional cell cluster size and geometry using two-dimensional patterning techniques is described. Cells were first cultured on two-dimensional micropatterned collagen using conventional soft lithography techniques. Collagenase was used to degrade the micropatterned collagen and release cells from the micropatterns, forming clusters of cells which were then resuspended in a three-dimensional collagen matrix. This method facilitated the formation of uniformly sized clusters within a single sample. By systematically varying the geometry of the two-dimensional micropatterned islands, final cluster size and cell number in three dimensions could be controlled. Using this technique, we showed that proliferation of cells within collagen gels depended on the size of clusters, suggesting an important role for multicellular structure on biological function. Furthermore, by utilizing more complex two-dimensional patterns, non-spherical structures could be produced. This technique demonstrates a simple way to exploit two-dimensional micro-patterning in order to create complex and structured multicellular clusters in a three-dimensional environment.
Larval behaviour of a giant damselfly: territoriality or size-dependent dominance?

Abstract Behavioural interactions and habitat use by larvae of the giant damselfly,Megaloprepus coerulatus, were studied in Panama. These larvae live in water-filled holes in fallen and living trees. Despite potential advantages for larval territoriality in this species,M. coerulatusdid not exhibit exclusive use of resources, probably because their prey were not spatially clumped. Both well-fed and starved larvae initiated agonistic displays typical of other damselfly species, and even small differences in relative size affected their behaviour towards conspecifics. Habitat use inM. coerulatusvaried with levels of food and cover. When cover was abundant, as it is in natural holes, larvae were hyper-dispersed. A larva rarely showed exclusive use of a given area from one day to the next, however, even when both cover and motile prey were experimentally limited. The ability of larger individuals to displace smaller ones as they move around the habitat is best described as size-dependent (and site-independent) dominance rather than territoriality. The results suggest that it is premature to characterize an animal as ‘territorial’ on the basis of its behaviour in the laboratory, unless the abundance and distribution of resources that are provided are realistic, and the experimental design is sufficient to differentiate between size-dependent dominance and site-specific exclusion of conspecifics from a critical resource.
NATIONAL ENTANGLEMENTS IN INTERNATIONAL GOVERNMENTAL ORGANIZATIONS

There has been a growing propensity among states to associate together in international governmental organizations, or IGOs, for a variety of purposes. Why do states join IGOs, and what are the consequences for states of membership in IGOs? In this analysis, an explanation is sought, drawing on the theory of functionalism espoused by David Mitrany and others, taking into account the number of years a state has had sovereignty, level of technology, extent of party competition, and overall power. For Third World states, membership in IGOs is associated with enhanced economic performance. An increasing number of IGOs in the system appears to lessen the states' mean proneness to war. Functionalist predictions are upheld. But functionalism needs to be supplemented both for comprehensive explanations and as a prescription for the future. Already there are so many IGOs that it is difficult for states to control them, which could make them progressively irrelevant or even jeopardize their existence.
The larynx ... so to speak: everything I wanted to know about laryngeal cancer I learned in the last 32 years.

Thirty-two years after treating laryngeal cancer for the first time, it is still exciting to watch the cancer disappear and the larynx return to normal. It is also just as disappointing to see a treatment failure or a poor functional result. It is even worse to recommend total laryngectomy for the advanced cases when you realize that some could be cured with radiotherapy and maintain a functioning, competent larynx. A few patients adapt amazingly well to a total laryngectomy, but, for most, their social life, ability to work, to talk on the phone, is seriously curtailed.
Gender, affiliation, assertion, and the interactive context of parent-child play

Ninety-eight young U.S. children (mean age = 48 months) with either European, Latin American, or multiple ethnic backgrounds were videotaped with their mothers and their fathers on separate occasions in their families' homes. Parent-child pairs played for 8 min each with a feminine-stereotyped toy set (foods and plates) and a masculine-stereotyped toy set (track and cars). Levels of affiliation (engaging vs. distancing) and assertion (direct vs. nondirect) were rated on 7-point scales every 5 s from the videotapes for both parent and child. Overall, the play activity accounted for a large proportion of the variance in parents' and children's mean affiliation and assertion ratings. Some hypothesized gender-related differences in behavior were also observed. In addition, exploratory analyses revealed some differences between the different ethnic groups. The results highlight the importance of role modeling and activity settings in the socialization and social construction of gender.
Empirically derived subtypes of social anxiety

A sample of socially anxious individuals were assessed for specific patterns of physiological reactivity and cognitions when engaged in a social encounter. Subjects were grouped according to independently derived empirical cutoffs on measures of cognition and physiological reactivity. The results indicated that the vast majority of socially anxious individuals demonstrate one of two response patterns. The first category consisted of those individuals who had negative thought content as well as high physiological reactivity. The second group also manifested negative cognition but were without the concomitant physiological reactivity. Results are discussed in terms of the applicability of an independently derived classification procedure for the socially anxious, and the possibility of matching therapeutic strategies to specific patterns of response.
Fram Strait: Exchange and dynamics

During November 18–20, 1986, a workshop entitled “Fram Strait: Exchange and Dynamics” was held at the National Oceanic and Atmospheric Administration (NOAA) Pacific Marine Environmental Laboratory in Seattle, Wash. A total of 27 talks were presented, and approximately 50 scientists attended. The principal issues addressed were the role of exchanges through Fram Strait in the regional and large-scale circulation and geochemical cycling and the factors driving and controlling flow through the strait. Fram Strait, between Greenland and Spitsbergen, is the deep passage between the Arctic Ocean and the North Atlantic extension in the Norwegian and Greenland seas (Figure 1).
Comments on genomic genera in the Triticeae (Poaceae)

Generic delimitation in the Triticeae has long been problematical because the extensive hybridization in the group is not readily accomodated in a hierarchical classification. The genomic genera of Love (1984) are one solution, but fully one-third of them are polyphyletic, incorporating 2 or more genomes. The suggestion that the tribe be considered a single genus (Stebbins, 1956) is theoretically defensible-the genus would be strictly monophyletic-but probably impractical. This paper presents a cladistic analysis of the tribe that differs from previous analyses in that it uses only strictly monophyletic (monogenomic) groups as terminal taxa; hybrids (heterogenomic groups) are shown as reticulations. Monophyletic groups can then be delimited to minimize the number of polyphyletic genera. A classification incorporating
Cognitive-versus-affective positivity asymmetries in thought systems

Positive-negative asymmetry in thought can involve both cognitive asymmetry, (thinking about characteristics that a stimulus has versus does not have), which we predict will be large and preponderantly a positivity bias, and affective asymmetry (thinking about desirable versus undesirable characteristics that the stimulus has or has not), predicted to be small and to fluctuate predictably in direction. The first four of the 10 studies reported here investigate asymmetries in thinking ability, measured by giving people directed-thinking tasks specifically asking them to generate positive versus negative thoughts. We predicted and found no affective asymmetry and a moderate-sized cognitive positivity bias that declines with practice. The second four of the 10 studies investigate asymmetries in proclivity (or preference beyond ability) that appear when people free associate on a variety of stimuli. As regards proclivity, we predicted and found a large, uniformly positive cognitive bias (that declines somewhat as children mature), but only a slight affective bias that is positive when autistic needs are dominant and negative when realistic needs dominate. A final pair of studies show that the cognitive and affective variables interact as regards how directed positive versus negative thinking about a stimulus affects evaluation of that stimulus.
The GE-100 data processing system

At the 1955 Eastern Joint Computer Conference, members of the Stanford Research Institute described a developmental prototype of a business data processor for accomplishing bank checking account bookkeeping. This paper describes the electronic data processing system evolved in the course of converting the developmental prototype into a production system capable of meeting the requirements of both satisfactory operation for banking and manufacturability.
Narrow Pressure Domain for Superconductivity in (TMTSEF)2ClO4

We present resistivity data for (TMTSeF)2C1O4 as a function of pressure. We find that the superconducting transition temperature (Tc) drops rapidly as pressure is increased from 1 bar (Tc≃1.3 K in ...
Finite element methods for the time-dependent Ginzburg-Landau model of superconductivity

Abstract The initial-boundary value problem for the time-dependent Ginzburg-Landau equations that model the macroscopic behavior of superconductors is considered. The convergence of finite-dimensional, semidiscrete Galerkin approximations is studied as is a fully-discrete scheme. The results of some computational experiments are presented.
Histone variants and chromatin structure during sea urchin development.

Abstract At the late blastula stage of sea urchin development a changeover of histone synthesis and chromatin composition takes place. Synthesis of the early histone variants declines while another set, the late histone variants, begins to be detected. During subsequent development the late histones accumulate steadily. In the 9-day larva only late histone variants are detectable. Micrococcal nuclease acts differentially on early and late nuclei. There is a depressed release of acid-soluble DNA when chromatin containing the late histones is digested. Nucleosomal repeat lengths change systematically and in parallel with the changing histone composition. Blastula and preblastula chromatin have a significantly shorter major repeat length than does the chromatin of 9-, 11-, and 16-day larvae. Intermediate stages of development have chromatin with intermediate periodicities. These differences are observed when the determinations are made under denaturing conditions of electrophoresis. Repeat lengths were found to be independent of the extent of digestion at all stages examined except the pluteus, in which there is an increase of the apparent repeat length as digestion proceeds. Pancreatic DNase I digests nuclei from blastulae and 9-day larvae similarly. Changes in the histone composition of chromatin, in nuclease accessibility of chromatin, and in nucleosomal repeat length are all very closely correlated, implying that there are underlying causal relationships.
The molecular basis of iron overload disorders and iron-linked anemias

Iron homeostasis in vertebrates requires coordination between cells that export iron into plasma and those that utilize or store plasma iron. The coordination of iron acquisition and utilization is mediated by the interaction of the peptide hormone hepcidin and the iron exporter ferroportin. Hepcidin levels are increased during iron sufficiency and inflammation and are decreased in hypoxia or erythropoiesis. Hepcidin is a negative regulator of iron export. Hepcidin binds to cell surface ferroportin inducing ferroportin degradation and decreasing cellular iron export. Genetic disorders of iron overload of iron-linked anemia can be explained by changes in the level of hepcidin or ferroportin and of the ability of ferroportin to be internalized by hepcidin.
Densitometric Quantitation of Urea, Carbamate, and Anilide Herbicides on C18 Reversed Phase Thin Layers Using Bratton-Marshall Detection Reagent

Abstract Twelve urea, carbamate, and anilide herbicides were detected on KC18 reversed phase thin layers with the Bratton-Marshall reagent after hydrolysis to produce aromatic amines. Spots were quantitated at the nanogram level by scanning with a densitometer. Analyses of spiked water and soil samples were carried out to demonstrate the practicality of the method.
Non-emergency small bowel obstruction: Assessment of CT findings that predict need for surgery

To identify CT findings predictive of surgical management in non-emergency small bowel obstruction (SBO). Contrast-enhanced abdominal CT of 129 patients with non-emergency SBO were evaluated for small bowel luminal diameter, wall thickness, presence of the small bowel faeces sign (intraluminal particulate matter in a dilated small bowel) and length, transition point, submucosal oedema, mesenteric stranding, ascites and degree of obstruction (low grade partial, high grade partial and complete obstruction). Medical records were reviewed for age, gender, management and history of abdominal surgery, abdominal malignancy, or SBO. Statistical analyses were performed with Stata Release 9.2. Degree of obstruction was the only predictor of need for surgery. Whereas 18.0% of patients with low-grade partial obstruction (n = 50) underwent surgery, 32.5% of patients with high-grade partial obstruction (n = 77) and 100% of patients with complete obstruction (n = 2) required surgery (P = 0.004). The small bowel faeces sign was inversely predictive of surgery (P = 0.018). In non-emergency SBO patients with contrast-enhanced CT imaging, grade of obstruction predicts surgery, while the small bowel faeces sign inversely predicts need for surgery.
Preventing Hospital-Acquired Infections: A National Survey of Practices Reported by U.S. Hospitals in 2005 and 2009

BACKGROUND Hospital-acquired infection (HAI) is common, costly, and potentially lethal. Whether initiatives to reduce HAI—such as the Centers for Medicare and Medicaid Services (CMS) no payment rule—have increased the use of preventive practices is not known.
The Quadratic Odds Estimation (QOE) Method for Calculating Practice Denominators

Primary care researchers in the U.S. have been frustrated by their inability to estimate the number of patients under the care of a physician in the fee-for-service system.1'2 The number of patients who come into a physician's office during a certain time, e.g., a year, is easily enumerated. What is not known is the number of patients in the population who would have come to see the physician if they had had a reason to do so. If it were possible to calculate how many such patients there are in the practice, the total size of the practice panel, or epidemiologic denominator, could then be estimated. It would be the sum of the known number of patients who visited the physician during the year and the estimate of the number of patients who did not visit during the year.