Computer program for predicting symmetric jet mixing of compressible flow in jets

Finite-difference computer program has been developed for treating mixing of two parallel and compressible air streams; one of them may be supersonic. This development is restricted to symmetric jet mixing in which high-speed jet is located on axis of channel and no provision is made for blowing or suction along channel walls

LANDSAT/coastal processes

The author has identified the following significant results. Correlations between the satellite radiance values water color, Secchi disk visibility, turbidity, and attenuation coefficients were generally good. The residual was due to several factors including systematic errors in the remotely sensed data, errors, small time and space variations in the water quality measurements, and errors caused by experimental design. Satellite radiance values were closely correlated with the optical properties of the water

Three-body interactions in complex fluids: virial coefficients from simulation finite-size effects

A simulation technique is described for quantifying the contribution of three-body interactions to the thermodynamical properties of coarse-grained representations of complex fluids. The method is based on comparing the third virial coefficient $B_3$ for a complex fluid with that of an approximate coarse-grained model described by a pair potential. To obtain $B_3$ we introduce a new technique which expresses its value in terms of the measured volume-dependent asymptote of a certain structural function. The strategy is applicable to both Molecular Dynamics and Monte Carlo simulation. Its utility is illustrated via measurements of three-body effects in models of star polymer and highly size-asymmetrical colloid-polymer mixtures.Comment: 13 pages, 8 figure

Climate Ready Estuaries - COAST in Action: 2012 Projects from Maine and New Hampshire

In summer 2011 the US EPA’s Climate Ready Estuaries program awarded funds to the Casco Bay Estuary Partnership (CBEP) in Portland, Maine, and the Piscataqua Region Estuaries Partnership (PREP) in coastal New Hampshire, to further develop and use COAST (COastal Adaptation to Sea level rise Tool) in their sea level rise adaptation planning processes. The New England Environmental Finance Center worked with municipal staff, elected officials, and other stakeholders to select specific locations, vulnerable assets, and adaptation actions to model using COAST. The EFC then collected the appropriate base data layers, ran the COAST simulations, and provided visual, numeric, and presentation-based products in support of the planning processes underway in both locations. These products helped galvanize support for the adaptation planning efforts. Through facilitated meetings they also led to stakeholders identifying specific action steps and begin to determine how to implement them

Two hard spheres in a pore: Exact Statistical Mechanics for different shaped cavities

The Partition function of two Hard Spheres in a Hard Wall Pore is studied appealing to a graph representation. The exact evaluation of the canonical partition function, and the one-body distribution function, in three different shaped pores are achieved. The analyzed simple geometries are the cuboidal, cylindrical and ellipsoidal cavities. Results have been compared with two previously studied geometries, the spherical pore and the spherical pore with a hard core. The search of common features in the analytic structure of the partition functions in terms of their length parameters and their volumes, surface area, edges length and curvatures is addressed too. A general framework for the exact thermodynamic analysis of systems with few and many particles in terms of a set of thermodynamic measures is discussed. We found that an exact thermodynamic description is feasible based in the adoption of an adequate set of measures and the search of the free energy dependence on the adopted measure set. A relation similar to the Laplace equation for the fluid-vapor interface is obtained which express the equilibrium between magnitudes that in extended systems are intensive variables. This exact description is applied to study the thermodynamic behavior of the two Hard Spheres in a Hard Wall Pore for the analyzed different geometries. We obtain analytically the external work, the pressure on the wall, the pressure in the homogeneous zone, the wall-fluid surface tension, the line tension and other similar properties

Lead abundance in the uranium star CS 31082-001

In a previous paper we were able to measure the abundance of uranium and thorium in the very-metal poor halo giant BPS CS 31082-001, but only obtained an upper limit for the abundance of lead (Pb). We have got from ESO 17 hours of additional exposure on this star in order to secure a detection of the minimum amount of lead expected to be present in CS 31082-001, the amount arising from the decay of the original content of Th and U in the star. We report here this successful detection. We find an LTE abundance log(Pb/H)+12=-0.55 \pm 0.15 dex, one dex below the upper limits given by other authors for the similar stars CS 22892-052 and BD +17d3248, also enhanced in r-process elements. From the observed present abundances of Th and U in the star, the expected amount of Pb produced by the decay of 232Th, and 238U alone, over 12-15 Gyr is -0.73\pm 0.17 dex. The decay of 235U is more difficult to estimate, but is probably slightly below the contribution of 238U, making the contribution of the 3 actinides only slightly below, or even equal to, the measured abundance. The contribution from the decay of 234U has was not included, for lack of published data. In this sense our determination is a lower limit to the contribution of actinides to lead production. We comment this result, and we note that if a NLTE analysis, not yet possible, doubles our observed abundance, the decay of the 3 actinides will still represent 50 per cent of the total lead, a proportion higher than the values considered so far in the literature.Comment: 4 pages, LateX, A&A Letters Accepte

XMM-Newton and INTEGRAL analysis of the Supergiant Fast X-ray Transient IGR J17354-3255

We present the results of combined INTEGRAL and XMM-Newton observations of the supergiant fast X-ray transient (SFXT) IGR J17354$-$3255. Three XMM-Newton observations of lengths 33.4 ks, 32.5 ks and 21.9 ks were undertaken, the first an initial pointing to identify the correct source in the field of view and the latter two performed around periastron. Simultaneous INTEGRAL observations across $\sim66\%$ of the orbital cycle were analysed but the source was neither detected by IBIS/ISGRI nor by JEM-X. The XMM-Newton light curves display a range of moderately bright X-ray activity but there are no particularly strong flares or outbursts in any of the three observations. We show that the spectral shape measured by XMM-Newton can be fitted by a consistent model throughout the observation, suggesting that the observed flux variations are driven by obscuration from a wind of varying density rather than changes in accretion mode. The simultaneous INTEGRAL data rule out simple extrapolation of the simple powerlaw model beyond the XMM-Newton energy range.Comment: 13 pages, 9 figures, This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society Published by Oxford University Pres

Z -> b\bar{b} Versus Dynamical Electroweak Symmetry Breaking involving the Top Quark

In models of dynamical electroweak symmetry breaking which sensitively involve the third generation, such as top quark condensation, the effects of the new dynamics can show up experimentally in Z->b\bar{b}. We compare the sensitivity of Z->b\bar{b} and top quark production at the Tevatron to models of the new physics. Z->b\bar{b} is a relatively more sensitive probe to new strongly coupled U(1) gauge bosons, while it is generally less sensitive a probe to new physics involving color octet gauge bosons as is top quark production itself. Nonetheless, to accomodate a significant excess in Z->b\bar{b} requires choosing model parameters that may be ruled out within run I(b) at the Tevatron.Comment: LaTex file, 19 pages + 2 Figs., Fermilab-Pub-94/231-

Evaluation of Three Rapid Tests for Diagnosis of P. Falciparum and P. Vivax Malaria in Colombia.

The diagnostic capacity of three malaria rapid diagnostic tests (RDTs), NOW-Malaria-ICT, OptiMAL-IT, and Paracheck-Pf, was evaluated against expert microscopy in Colombia. We tested 896 patients, of whom microscopy confirmed 139 P. falciparum, 279 P. vivax, and 13 mixed P.f/P.v infections and 465 negatives. Paracheck-Pf and NOW-malaria-ICT were more accurate in detecting P. falciparum (sensitivities 90.8% and 90.1%, respectively) in comparison with Optimal-IT (83.6%). NOW showed an acceptable Pf detection rate at low densities (< 500/microL), but resulted in a higher proportion of false positives. For P. vivax diagnosis, Optimal-IT had a higher sensitivity than NOW (91.0% and 81.4%, respectively). The choice between the two Pf/Pv detecting RDTs balances P. falciparum and P. vivax detection rates. Considering some degree of P. falciparum overtreatment and failure to detect all P. vivax cases as more acceptable than missing some cases of P. falciparum, we recommend careful implementation of NOW-malaria-ICT in areas where microscopy is lacking. The price is however still a constraint