Magnetic Cataclysmic Variable Accretion Flows

We have used a magnetic accretion model to investigate the accretion flows of magnetic cataclysmic variables (mCVs) throughout a range of parameter space. The results of our numerical simulations demonstrate that broadly four types of flow are possible: discs, streams, rings and propellers. We show that the equilibrium spin periods in asynchronous mCVs, for a given orbital period and magnetic moment, occur where the flow changes from a type characterised by spin-up (i.e. disc or stream) to one characterised by spin-down (i.e. propeller or ring). 'Triple points' occur in the plane of spin-to-orbital period ratio versus magnetic moment, at which stream-disc-propeller flows or stream-ring-propeller flows can co-exist. The first of these is identified as corresponding to when the corotation radius is equal to the circularisation radius, and the second as where the corotation radius is equal to the distance from white dwarf to the L1 point. If mCVs are accreting at their equilibrium spin rates, then for a mass ratio of 0.5, those with Pspin/Porb < 0.1 will be disc-like, those with 0.1 < Pspin/Porb < 0.5 will be stream-like, and those with Pspin/Porb ~ 0.5 will be ring-like. In each case, some material is also lost from the binary in order to maintain angular momentum balance. The spin to orbital period ratio at which the systems transition between these flow types decreases as the mass ratio of the stellar components increases, and vice versa

RXTE confirmation of the intermediate polar status of IGR J15094-6649

Aims. To establish the X-ray properties of the intermediate polar candidate IGR J15094-6649 and therefore confirm its inclusion into the class. Methods. 42 856 s of X-ray data from RXTE was analysed. Frequency analysis was used to constrain temporal variations and spectral analysis used to characterise the emission and absorption properties. Results. A spin period of 809.7+-0.6 s is present, revealed as a complex pulse profile whose modulation depth decreases with increasing X-ray energy. The spectrum is well fitted by either a 19+-4 keV Bremsstrahlung or Gamma=1.8+-0.1 power law, with an iron emission line feature and significant absorption in each case. Conclusions. IGR J15094-6649 is confirmed to be an intermediate polar.Comment: 3 pages, 5 figures. Submitted to A&

AGRICULTURAL COOPERATION AND PRODUCE MARKETING IN SOUTHWEST VIRGINIA

Growers and community leaders have expressed interest in establishing a horticultural shipping-point market in Southwest Virginia. This paper reports on a study that assessed whether horticultural production would be profitable in the region and, if so, the physical and organizational requirements for a successful shipping-point market. It appears that tomatoes, peppers, and pumpkins can be produced and marketed profitably to large-volume wholesale buyers if growers meet the exacting requirements of the retailers. A cooperative association is the organizational structure with the greatest chance of success. At the conclusion of this study, a shipping-point market in the recommended form was established in Southwest Virginia.Agribusiness, Marketing,

The effects of condensed tannins from Desmodium intortum and Calliandra calothyrsus on protein and carbohydrate digestion in sheep and goats

A factorial experiment was conducted to study the effects of condensed tannins (CT) from the tropical legumes Desmodium intortum and Calliandra calothyrus on the digestion and utilization of protein and carbohydrate in sheep and goats. CT-free Centrosema pubescens was also fed for comparison with the CT legumes, and each legume was included (300 g/kg DM) in a basal diet of pangola grass (Digitaria decumbens). Pangola grass alone was used as a control diet. There were no significant (P > 0.05) differences between sheep and goats for the efficiency of digestion of N (0.574, se 0.013), organic matter (OM; 0.519, SE 0.010), neutral-detergent fibre (NDF; 0.524, SE 0.011) and acid-detergent fibre (ADF; 0.407, SE 0.016). Diets containing desmodium and calliandra were digested less well in the rumen (64 and 62% of total OM digested) when compared with the pangola and centrosema diets (74 and 73% of total OM digested in rumen). There was an apparent net gain of 30% in ADF across the digestive tract sheep and goats given calliandra, and this gain was ascribed to the formation of 'artifact' fibre as a result of fibre-tannin interaction. Overall, inclusion of legume at 300 g/kg in the diet significantly increased (P 0.05) since animals given CT diets absorbed more N (19%) per kg total OM digested than those given the control diets. It was concluded that whilst the low levels of CT provided in desmodium (1.0%) and calliandra (2.3%) diets protected dietary protein from degradation in the rumen, there were no overall beneficial or detrimental effects of CT in these diets for sheep or goats. A method was developed to categorize CT into fractions representative of their forms (free, protein-bound, and fibre-bound) during the digestion process. A quantitative model of CT metabolism during passage through the digestive tract was developed from the measured exchanges of CT between free, protein-bound and fibre-bound pools in the rumen and lower digestive tract. CT interchange mainly occurred in the reticulo-rumen of both animal species. Desmodium and calliandra free CT showed net losses of 68 and 78% in the rumen respectively and 57 and 68% of the fibre-bound CT was lost in the same site for sheep and goats respectively. However, protein-bound CT increased across the rumen by 73 and 56% for both animal species. Post-rumen losses of the total CT abomasal flow were 86 and 83% (free CT) for sheep and goats respectively, 70 and 66% (protein-bound CT), whilst 28% loss of fibre-bound CT occurred in sheep and goats respectively

Fly-by-light flight control system technology development plan

The results of a four-month, phased effort to develop a Fly-by-Light Technology Development Plan are documented. The technical shortfalls for each phase were identified and a development plan to bridge the technical gap was developed. The production configuration was defined for a 757-type airplane, but it is suggested that the demonstration flight be conducted on the NASA Transport Systems Research Vehicle. The modifications required and verification and validation issues are delineated in this report. A detailed schedule for the phased introduction of fly-by-light system components has been generated. It is concluded that a fiber-optics program would contribute significantly toward developing the required state of readiness that will make a fly-by-light control system not only cost effective but reliable without mitigating the weight and high-energy radio frequency related benefits

No Wedding Bells For Her

https://digitalcommons.library.umaine.edu/mmb-vp/4549/thumbnail.jp

Sing Me A Song Of The South

https://digitalcommons.library.umaine.edu/mmb-vp/6493/thumbnail.jp