Evaluation of thermal soak times

A mathematical model for the heat transfer within the electronics package of a Chaparral missile was performed. The Grashof number for this configuration was less than 2000 which indicated that the primary mode of heat transfer was conduction. The Vodicka theory for heat conduction in laminated composite media was utilized to obtain the solution for the model

Educating for Entrepreneurial Leadership: From Didacticism to Co-creation

Entrepreneurial leadership promotes organisational competitive advantage and innovation resulting in increased attention on entrepreneurial leadership development. Many higher education institutions (HEIs) claim to develop entrepreneurial leaders. However, knowledge of how to facilitate entrepreneurial leadership development is limited, the effectiveness of development practices is contestable, and current understanding of the phenomenon is mostly conceptual. We address this void by exploring educators’ perspectives of entrepreneurial leadership development and consider how the phenomenon is facilitated. We employ Interpretative Phenomenological Analysis (IPA) as our research methodology and analyse the data following IPA data analysis guidance. Findings signify the importance of placing strong emphasis on co-creating education experience with wider stakeholder involvement, thereby forming an entrepreneurial community which works collectively over the longer-term to facilitate entrepreneurial leadership development. The findings also reveal the pedagogic significance of facilitating supportive learning conditions and ‘handholding,’ a broader form of support which contradicts the established notion of ‘independent learners’ thereby challenging current ontologies around ‘student support’ when facilitating entrepreneurial leadership development

Coexistence of supravalvular aortic stenosis and osteogenesis imperfecta.

A 54 year old woman was admitted for cardiac catheterisation. She had-been attending the outpatient clinic since 1975, with regular review. She had diagnoses of type I osteogenesis imperfecta, and of supravalvular aortic stenosis. Osteogenesis imperfecta was diagnosed in early life on clinical grounds including the presence of blue sclerae and the occurrence of several bone fractures secondary to minimal trauma. A number of family members have been diagnosed with the same condition (figure 1-family pedigree). The supravalvular aortic stenosis was not diagnosed until later. She was initially referred to the cardiology clinic for further evaluation following the discovery of a systolic murmu

Polarization transfer in wide-angle Compton scattering and single-pion photoproduction from the proton

Wide-angle exclusive Compton scattering and single-pion photoproduction from the proton have been investigated via measurement of the polarization transfer from a circularly polarized photon beam to the recoil proton. The wide-angle Compton scattering polarization transfer was analyzed at an incident photon energy of 3.7 GeV at a proton scattering angle of θpcm=70°. The longitudinal transfer KLL, measured to be 0.645±0.059±0.048, where the first error is statistical and the second is systematic, has the same sign as predicted for the reaction mechanism in which the photon interacts with a single quark carrying the spin of the proton. However, the observed value is ∼3 times larger than predicted by the generalized-parton-distribution-based calculations, which indicates a significant unknown contribution to the scattering amplitude

Database of Diazotrophs in Global Ocean: Abundance, Biomass, and Nitrogen Fixation Rates

Marine N2 fixing microorganisms, termed di-azotrophs, are a key functional group in marine pelagic ecosystems. The biological fixation of dinitrogen (N2) to bioavailable nitrogen provides an important new source of nitrogen for pelagic marine ecosystems and influences primary productivity and organic matter export to the deep ocean. As one of a series of efforts to collect biomass and rates specific to different phytoplankton functional groups, we have constructed a database on diazotrophic organisms in the global pelagic upper ocean by compiling about 12 000 direct field measurements of cyanobacterial diazotroph abundances (based on microscopic cell counts or qPCR assays targeting the nifH genes) and N2 fixation rates. Biomass conversion factors are estimated based on cell sizes to convert abundance data to diazotrophic biomass. The database is limited spatially, lacking large regions of the ocean especially in the Indian Ocean. The data are approximately log-normal distributed, and large variances exist in most sub-databases with non-zero values differing 5 to 8 orders of magnitude. Reporting the geometric mean and the range of one geometric standard error below and above the geometric mean, the pelagic N2 fixation rate in the global ocean is estimated to be 62 (52-73) Tg N yr-1 and the pelagic diazotrophic biomass in the global ocean is estimated to be 2.1 (1.4-3.1) Tg C from cell counts and to 89 (43-150) Tg C from nifH- based abundances. Reporting the arithmetic mean and one standard error instead, these three global estimates are 140 ± 9.2 Tg Nyr-1, 18 ± 1.8 Tg C and 590 ± 70 Tg C, respectively. Uncertainties related to biomass conversion factors can change the estimate of geometric mean pelagic diazotrophic biomass in the global ocean by about ± 70 %. It was recently established that the most commonly applied method used to measure N2 fixation has underestimated the true rates. As a result, one can expect that future rate measurements will shift the mean N2 fixation rate upward and may result in significantly higher estimates for the global N2 fixation. The evolving database can nevertheless be used to study spatial and temporal distributions and variations of marine N2 fixation, to validate geochemical estimates and to parameterize and validate biogeochemical models, keeping in mind that future rate measurements may rise in the future