Complexity and white-dwarf structure

From the low-mass non-relativistic case to the relativistic limit, the density profile of a white dwarf is used to evaluate the complexity measure. Similarly to the recently reported atomic case where, by averaging shell effects, complexity grows with the atomic number, here complexity grows as a function of the star mass reaching a maximum finite value in the Chandrasekhar limit.Comment: 9 pages and 4 figure

The virial theorem and the atmosphere

In our atmosphere, most of the energy resides as internal energy, U, and gravitational energy P, and the proportionality U/P = cV /R = 5/2 is maintained in an air column provided there is hydrostatic equilibrium. In this paper we show that this result is a consequence of the virial theorem

A maximum entropy profile for the mesosphere

Following a recent work by Verkley and Gerkema, we obtain a pressure-temperature profile for the mesosphere which reproduces rather well the U.S. Standard Atmosphere, 1976 data and the COSPAR International Reference Atmosphere, 1972 as well. This profile results from the maximization of entropy in a column of air in hydrostatic equilibrium, maintaining fixed the mass, the enthalpy and the vertical integral of the potential temperature

Temporal Trends of Dissolved Trace Metals in Jamaica Bay, NY: Importance of Wastewater Input and Submarine Groundwater Discharge in an Urban Estuary

Jamaica Bay, NY, is a highly urbanized estuary within the boroughs of New York City conspicuously lacking published information on dissolved trace metal concentrations. The current study examines the distribution and cycling of trace metals in that embayment with data gathered during cruises in November 2004, April 2005, and June 2006. Most of the metal distributions (Fe, Zn, Co, Ag, Cu, Pb, Ni) in the water column are explained by the input of substantial volumes of treated wastewater effluent. However, several lines of evidence suggest that submarine groundwater discharge (SGD) is also an important source of dissolved Fe, Zn, Co, Ni, and isotopically distinct stable Pb ratios (206Pb, 207Pb, 208Pb) in the Bay. Conversely, the recirculated seawater component of SGD is an apparent sink for dissolved Mo. This study provides the first measurements of dissolved trace metals in the Jamaica Bay water column and subterranean estuary and provides evidence for trace metal input due to SGD

A Three-Dimensional Dynamic Supramolecular "Sticky Fingers" Organic Framework.

Engineering high-recognition host-guest materials is a burgeoning area in basic and applied research. The challenge of exploring novel porous materials with advanced functionalities prompted us to develop dynamic crystalline structures promoted by soft interactions. The first example of a pure molecular dynamic crystalline framework is demonstrated, which is held together by means of weak "sticky fingers" van der Waals interactions. The presented organic-fullerene-based material exhibits a non-porous dynamic crystalline structure capable of undergoing single-crystal-to-single-crystal reactions. Exposure to hydrazine vapors induces structural and chemical changes that manifest as toposelective hydrogenation of alternating rings on the surface of the [60]fullerene. Control experiments confirm that the same reaction does not occur when performed in solution. Easy-to-detect changes in the macroscopic properties of the sample suggest utility as molecular sensors or energy-storage materials

Complexity analysis of Klein-Gordon single-particle systems

The Fisher-Shannon complexity is used to quantitatively estimate the contribution of relativistic effects to on the internal disorder of Klein-Gordon single-particle Coulomb systems which is manifest in the rich variety of three-dimensional geometries of its corresponding quantum-mechanical probability density. It is observed that, contrary to the non-relativistic case, the Fisher-Shannon complexity of these relativistic systems does depend on the potential strength (nuclear charge). This is numerically illustrated for pionic atoms. Moreover, its variation with the quantum numbers (n, l, m) is analysed in various ground and excited states. It is found that the relativistic effects enhance when n and/or l are decreasing.Comment: 4 pages, 3 figures, Accepted in EPL (Europhysics Letters

Field study of infiltration capacity reduction of porous mixture surfaces

Porous surfaces have been used all over the world in source control techniques to minimize flooding problems in car parks. Several studies highlighted the reduction in the infiltration capacity of porous mixture surfaces after several years of use. Therefore, it is necessary to design and develop a new methodology to quantify this reduction and to identify the hypothetical differences in permeability between zones within the same car park bay due to the influence of static loads in the parked vehicles. With this aim, nine different zones were selected in order to check this hypothesis (four points under the wheels of a standard vehicle and five points between wheels). This article presents the infiltration capacity reduction results, using the LCS permeameter, of Polymer-Modified Porous Concrete (9 bays) and Porous Asphalt (9 bays) surfaces in the University of Cantabria Campus parking area (Spain) 5 years after their construction. Statistical analysis methodology was proposed for assessing the results. Significant differences were observed in permeability and reduction in infiltration capacity in the case of porous concrete surfaces, while no differences were found for porous asphalt depending on the measurement zone

Carcass and meat quality in light lambs from different classes in the European grading system

Fat, quantity and quality, are important aspects for consumers (Sendim et al., 1997), who are more and more interested in healthy products and usually prefer lean meat and carcasses, although fat is positively associated with acceptability. Thus, Jeremiah (1998) found that the percentage of unacceptable cuts was higher in lean than fat categories, similar findings being obtained by Paul et al., ( 1964) and Smith et al., (1970). For this reason practically all carcass classification systems around the world include fatness score as a criterion of quality and price (EEC n° 2 137/92 and 46 1/93 regulations; Moxhan and Brownlie (1976)). Other characteristics such as age, sex, weight, carcass length, meat colour and specially conformation score are also used, but they have a lower market significance and a lower price influence. Inside the EU there are two different schemes for lamb classification: one for carcasses up 13 kg and other for light carcasses under 13 kg. In the latter scheme, since Mediterranean carcasses were systematically penalised because of their natural poor morphology (walker breeds), low subcutaneous/internal fat ratio and light weights, conformation score is not considered. Only weight (three categories: < 7.0 kg, 7.1-10.0 kg and 10.1-13.0 kg), meat colour and fat class are included Several studies have shown weak relationships between lamb quality grades and palatability assessments in heavy or medium weight carcasses (Jeremiah et al., 1972; Crouse and Ferrel, I 982), but there has been no investigation of this relationship in light lambs. On the other hand, it seems essential to know if any classification is, or is not, related with real carcass value and quality

Carcass and meat quality in light lambs from different fat classes in the EU carcass classification system

Ninety commercial lamb carcasses were analysed according to the four different fat classes in the light lamb European classiffication system. Shoulder fat increased 3%, muscle decreased 2% and bone decreased 1% for each class increase. No signifficant differences were found among fat classes regarding pH, WHC, cooking losses, juiciness, myoglobin content, meat colour measured immediately after cutting (L*, a*, b*), odour intensity or flavour quality. Some differences were found in colour evolution through ageing. Shear force decreased and tenderness and flavour intensity increased with fat class but this effect was only signifficant in the leanest animals