Gas separation membrane

A method of fabricating a gas separation membrane includes providing a coextruded multilayer film that includes a first polymer layer formed of a first polymer material and a second polymer layer formed of a second polymer material, the first polymer material having a first gas permeability. The coextruded multilayer film is axially oriented such that the second polymer layer has a second gas permeability that is greater than the first gas permeability.Board of Regents, University of Texas Syste

Zeros of the i.i.d. Gaussian power series: a conformally invariant determinantal process

Consider the zero set of the random power series f(z)=sum a_n z^n with i.i.d. complex Gaussian coefficients a_n. We show that these zeros form a determinantal process: more precisely, their joint intensity can be written as a minor of the Bergman kernel. We show that the number of zeros of f in a disk of radius r about the origin has the same distribution as the sum of independent {0,1}-valued random variables X_k, where P(X_k=1)=r^{2k}. Moreover, the set of absolute values of the zeros of f has the same distribution as the set {U_k^{1/2k}} where the U_k are i.i.d. random variables uniform in [0,1]. The repulsion between zeros can be studied via a dynamic version where the coefficients perform Brownian motion; we show that this dynamics is conformally invariant.Comment: 37 pages, 2 figures, updated proof

Which executive functioning deficits are associated with AD/HD, ODD/CD and comorbid AD/HD+ODD/CD?

Item does not contain fulltextThis study investigated (1) whether attention deficit/hyperactivity disorder (AD/HD) is associated with executive functioning (EF) deficits while controlling for oppositional defiant disorder/conduct disorder (ODD/CD), (2) whether ODD/CD is associated with EF deficits while controlling for AD/HD, and (3)~whether a combination of AD/HD and ODD/CD is associated with EF deficits (and the possibility that there is no association between EF deficits and AD/HD or ODD/CD in isolation). Subjects were 99~children ages 6–12 years. Three putative domains of EF were investigated using well-validated tests: verbal fluency, working memory, and planning. Independent of ODD/CD, AD/HD was associated with deficits in planning and working memory, but not in verbal fluency. Only teacher rated AD/HD, but not parent rated AD/HD, significantly contributed to the prediction of EF task performance. No EF deficits were associated with ODD/CD. The presence of comorbid AD/HD accounts for the EF deficits in children with comorbid AD/HD+ODD/CD. These results suggest that EF deficits are unique to AD/HD and support the model proposed by R. A. Barkley (1997).17 p

Preventing Violence in Seven Countries: Global Convergence in Policies

Do governments take the measures that are supported by the best scientific evidence available? We present a brief review of the situation in: Australia, Canada, Germany, the Netherlands, Spain, the United Kingdom, and the United States. Our findings show surprisingly similar developments across countries. While all seven countries are moving towards evidence-based decision making regarding policies and programs to prevent violence, there remain a number of difficulties before this end can be achieved. For example, there continue to be few randomized controlled trials or rigorous quasi-experimental studies on aggression and violence. Results from experimental research are essential to both policy makers and researchers to determine the effectiveness of programs as well as increase our knowledge of the problem. Additionally, all noted that media attention for violence is high in their country, often leading to management by crisis with the result that policies are not based on evidence, but instead seek to appease public outrage. And perhaps because of attendant organizational problems (i.e., in many countries violence prevention was not under the guise of one particular agency or ministry), most have not developed a coordinated policy focusing on the prevention of violence and physical aggression. It is hypothesized that leaders in democratic countries, who must run for election every 4 to 6 years, may feel a need to focus on short-term planning rather than long-term preventive policies since the costs, but not the benefits for the latter would be incurred while they still served in office. We also noted a general absence of expertise beyond those within scientific circles. The need for these ideas to be more widely accepted will be an essential ingredient to real and sustaining change. This means that there must be better communication and increased understanding between researchers and policy makers. Toward those ends, the recent establishment of the Campbell Collaboration, formed to provide international systematic reviews of program effectiveness, will make these results more available and accessible to politicians, administrators and those charged with making key policy decision

A research agenda for seed-trait functional ecology

Trait-based approaches have improved our understanding of plant evolution, community assembly and ecosystem functioning. A major challenge for the upcoming decades is to understand the functions and evolution of early life-history traits, across levels of organization and ecological strategies. Although a variety of seed traits are critical for dispersal, persistence, germination timing and seedling establishment, only seed mass has been considered systematically. Here we suggest broadening the range of morphological, physiological and biochemical seed traits to add new understanding on plant niches, population dynamics and community assembly. The diversity of seed traits and functions provides an important challenge that will require international collaboration in three areas of research. First, we present a conceptual framework for a seed ecological spectrum that builds upon current understanding of plant niches. We then lay the foundation for a seed-trait functional network, the establishment of which will underpin and facilitate trait-based inferences. Finally, we anticipate novel insights and challenges associated with incorporating diverse seed traits into predictive evolutionary ecology, community ecology and applied ecology. If the community invests in standardized seed-trait collection and the implementation of rigorous databases, major strides can be made at this exciting frontier of functional ecology

Attention Performance in an Epidemiological Sample of Urban Children: The Role of Gender and Verbal Intelligence

We administered a comprehensive attentional battery to an epidemiologically defined sample of 435 first and second-grade children to assess the influence of gender and verbal intelligence on attention. The battery included three versions of the continuous performance test (CPT), two digit cancellation tasks, three subtests from the WISC-R, and the Wisconsin Card Sorting Test. The results indicated that both gender and intelligence had an impact on attentional performance. Girls performed better than boys; they made fewer errors on the CPT and obtained higher scores on the digit cancellation task and the Coding subtest of the WISC-R. Children with higher verbal intelligence also performed better on the attentional tests, but this advantage was not observed across measures or levels of performance. For example, children with limited verbal skills performed significantly worse than their peers only in measures with high processing demands(the degraded CPT and the distraction version of the digit cancellation task)