The Development of High Order Numerical Techniques for Reentry Simulation of Hypersonic Spacecraft

The primary difficulty encountered when simulating hypersonic flow is that the flow normally includes strong nonlinear discontinuities. These discontinuities fall into three broad classes: shocks, slip-lines, and rarefaction waves. Moreover, in the hypersonic flow regime, the chemistry of hot gases plays a vital role and can not be neglected. These facts combine to make the numerical treatment of spacecraft reentry a most challenging problem. In this work, we develop a class of finite difference schemes that accurately resolve discontinuous solutions to spacecraft reentry flow and are simple to incorporate into existing spacecraft reentry codes

Vaccination nation? Civilised strategies for protecting outdoor poultry from Avian Flu H5N1

An analysis of the threat of H5N1 Avian Flu virus to the UK, the potential impact on UK organic and free range poultry production and the evidence for a policy of vaccination

A hybrid multigrid technique for computing steady-state solutions to supersonic flows

Recently, Li and Sanders have introduced a class of finite difference schemes to approximate generally discontinuous solutions to hyperbolic systems of conservation laws. These equations have the form together with relevant boundary conditions. When modelling hypersonic spacecraft reentry, the differential equations above are frequently given by the compressible Euler equations coupled with a nonequilibrium chemistry model. For these applications, steady state solutions are often sought. Many tens (to hundreds) of super computer hours can be devoted to a single three space dimensional simulation. The primary difficulty is the inability to rapidly and reliably capture the steady state. In these notes, we demonstrate that a particular variant from the schemes presented can be combined with a particular multigrid approach to capture steady state solutions to the compressible Euler equations in one space dimension. We show that the rate of convergence to steady state coming from this multigrid implementation is vastly superior to the traditional approach of artificial time relaxation. Moreover, we demonstrate virtual grid independence. That is, the rate of convergence does not depend on the degree of spatial grid refinement

Why All Published Research Findings Are Likely False (and a possible remedy)

The physiological constraints of our neuro-sensory instrumentation limit the information we receive and from which we fashion our impressions. These limitations precede the psychological issues of data generation and analysis described by Ioannidis [1]. Scientific models widely accepted for at least 50 years [2,3] suggest that the peripheral and central nervous systems do not provide direct information about phenomena as they exist in nature. Instead, perceptible phenomena stimulate sense organs to produce nerve impulses. Sensory nerve impulses are not replicas of the phenomena stimulating their production. The brain, by obscure mechanisms, then fabricates personal experience from the sensory nerve impulses. The relationship of phenomena to the brain's experiential construct is unknown. Since evidence is produced by sense organs and the brain (neither of which incorporates bona fide replicas of phenomena), all scientific conclusions are likely false in the sense that they are not based on direct knowledge of phenomena as they exist in nature

A contribution to the orchidology of Tasmania

Slightly hairy, very slender, about 6.5-15 cm. high, a cylindrical sheath at the base. The leaf incomplete in my specimens, narrow linear, almost glabrous, a1pparently rather long. Flowers 1-3; pedicels slender, rather long, subtended by a narrow acute bract. Segments of perianth somewhat similar, dusky and glandular-hairy on the outer side; lateral sepals spreading, elliptical, acute, about 1.2-1.5 cm. long, 4 mm. wide, 5-7-veined; dorsal sepal erecto-incurved, slightly concave, about 1.1-1.2 cm. long, 3 mm. wide, subacute, lanceolate; p·etals fal.co-elliptical, acute, spreading, 5-nerved, a:bout 1.1-1.2 cm. long, 2.5 mm. wide. Labellum clawed, nearly equal in length to the column, transv·ersely barred, 3- lobed; lateral lobes large rounded entire or slightly notched anteriorly, middle lobe triangular 1:ecurvEd with pectinate or denticulate margins; -caili in 4 rows, linear, bent, be-coming s~orter towards the apex. Golumn ereeto-incurved, rather Widely winged above, transversely barred. Anther shortly mucronate

Engineering Coexistence

A response to the issues raised by the English GM coexistence consultation

Condoms are more effective when applied by males: a study of young black males in the United States

PurposeTo determine, among a sample of young black male (YBM), whether female application of male condoms for penile–vaginal intercourse would be associated with higher or lower rates of breakage or slippage. A secondary aim was to investigate if higher rates of breakage or slippage were associated with increased odds of acquiring chlamydia and/or gonorrhea.MethodsA cross-sectional study of 412 YBM, aged 15 to 23 years, was conducted in three US cities located in the Southern United States.ResultsAmong YBM reporting frequent female application of condoms, 43.5% reported one or more instance of breakage or slippage, compared with those reporting less frequent female application (27.2%, P = .003). Among YBM reporting one or more event of breakage or slippage, 25.4% tested positive for chlamydia and/or gonorrhea. In contrast, among those not reporting breakage or slippage, 17.2% tested positive (P = .047).ConclusionsFindings suggest that educational and behavioral interventions should seek to improve young women's skills relative to condom application and use. Further studies could also investigate whether intervention efforts should encourage some YBM to be responsible for their own condom application

ECONOMICS OF SWINE CROSSBREEDING SYSTEMS

Livestock Production/Industries,

Comparison of enzyme-linked immunosorbent assay, surface plasmon resonance and biolayer interferometry for screening of deoxynivalenol in wheat and wheat dust

A sample preparation method was developed for the screening of deoxynivalenol (DON) in wheat and wheat dust. Extraction was carried out with water and was successful due to the polar character of DON. For detection, an enzyme-linked immunosorbent assay (ELISA) was compared to the sensor-based techniques of surface plasmon resonance (SPR) and biolayer interferometry (BLI) in terms of sensitivity, affinity and matrix effect. The matrix effects from wheat and wheat dust using SPR were too high to further use this screenings method. The preferred ELISA and BLI methods were validated according to the criteria established in Commission Regulation 519/2014/EC and Commission Decision 2002/657/EC. A small survey was executed on 16 wheat lots and their corresponding dust samples using the validated ELISA method. A linear correlation (r = 0.889) was found for the DON concentration in dust versus the DON concentration in wheat (LOD wheat: 233 g/kg, LOD wheat dust: 458 g/kg)