Weak Lensing from Space I: Instrumentation and Survey Strategy

A wide field space-based imaging telescope is necessary to fully exploit the technique of observing dark matter via weak gravitational lensing. This first paper in a three part series outlines the survey strategies and relevant instrumental parameters for such a mission. As a concrete example of hardware design, we consider the proposed Supernova/Acceleration Probe (SNAP). Using SNAP engineering models, we quantify the major contributions to this telescope's Point Spread Function (PSF). These PSF contributions are relevant to any similar wide field space telescope. We further show that the PSF of SNAP or a similar telescope will be smaller than current ground-based PSFs, and more isotropic and stable over time than the PSF of the Hubble Space Telescope. We outline survey strategies for two different regimes - a ``wide'' 300 square degree survey and a ``deep'' 15 square degree survey that will accomplish various weak lensing goals including statistical studies and dark matter mapping.Comment: 25 pages, 8 figures, 1 table, replaced with Published Versio

Cooperating to commercialize technology: A dynamic model of fairness perceptions, experience, and cooperation

Technology entrepreneurship is an important driver of economic growth, although entrepreneurs must maintain cooperative ties with the owners of any technology they hope to bring to market. Existing studies show that fairness perceptions have a great influence on this cooperation, but no research investigates its precise mechanisms or dynamic patterns. This study explores the development of 17 ventures that cooperated with a university-owner of technology and thereby identifies different cooperation patterns in which fairness perceptions influence the degree of cooperation. These perceptions also change over time, partly as a function of accumulated experience and learning. A system dynamics model integrates insights from existing literature with the empirical findings to reveal which cooperation mechanisms relate to venture development over time; the combinations of individual experience, fairness perceptions, and market circumstances lead to four different patterns. This model can explain changes in entrepreneurial cooperation as a result of changes in fairness perceptions, which depend on learning effects and entrepreneurial experience. Each identified cooperation pattern has implications for research and offers insights for practitioners who need to manage relationships in practice

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

The effect of firms’ relational capabilities on knowledge acquisition and co-creation

This study examines how firms’ relational capabilities influence two main approaches to sourcing knowledge from universities, namely, acquiring and co-creating knowledge. By adopting a sequential mixed methods design to gather empirical evidence from firms that interact with universities, it contributes to unravelling the puzzle presented in the literature on the positive effects and drawbacks of relational capabilities. We find that the balance between the opposing effects of relational capabilities differs depending on the knowledge sourcing approach. While capabilities for aligning goals, objectives, and routines/practices between firms and academics are of significant importance only for knowledge co-creation, Communication capabilities are important for both, with greater significance for knowledge acquisition. We highlight implications about what relational capabilities firms should nurture in order to best source knowledge from universities

Entry and Technological Performance in New Technology Domains:Technological Opportunities, Technology Competition and Technological Relatedness

Entry and success in new technology domains (NTDs) is essential for firms' long-term performance. We argue that firms' choices to enter NTDs and their subsequent performance in these domains are not only governed by firm-level factors but also by environmental characteristics. Entry is encouraged by the richness of opportunities for technology development, while technology competition by incumbent firms discourages entry and render entries that do take place less successful. Firms are expected to be positioned heterogeneously to recognize and capitalize on technological opportunities, depending on the presence of a related technology base. We find qualified support for these conjectures in a longitudinal analysis of entry and technological performance in NTDs by 176 R&D intensive firms. While opportunity rich technology environments attract entries by firms even if these NTDs are distal from firms' existing technologies, firms require related technological expertise in order to exploit technological opportunities post-entry

Testing a conceptual model related to weight perceptions, physical activity, and smoking in adolescents

The purpose of this study was to test a conceptual model based on theoretical and empirically supported relationships related to the influences of weight perceptions, weight concerns, desires to change weight, friends, age and location in relation to physical activity (PA) and smoking in adolescents. A total of 1242 males and 1446 females (mean age = 15.6 ± 1.3) were recruited from rural and urban Canadian schools. Study respondents provided self-reports of PA, ‘smoking’, ‘perceived body weight’, ‘desire to change weight’, ‘concern about weight gain’ and ‘friends' smoking and PA behaviors’. Results revealed an acceptable fitting model χ2 (40) = 155.63, P < 0.05, root mean square error of approximation = 0.047 and comparative fit index = 0.98. Large effect sizes for both genders were observed between friends' and adolescents' smoking behavior, and between perceived body weight and desire to change weight. Further, significant differences were identified between the male and female models [χ2 difference (24) = 65.28, P < 0.05]. Several findings of this study point to the need to design programs to motivate adolescent females to adopt healthy weight-control practices and to target young peoples' social networks to promote health behaviors, especially with regard to smoking