Effectiveness evaluation of STOL transport operations

A short-takeoff and landing (STOL) systems simulation model has been developed and implemented in a computer code (known as STOL OPS) which permits evaluation of the operation of a STOL aircraft and its avionics in a commercial airline operating environment. STOL OPS concentrated on the avionics functions of navigation, guidance, control, communication, hazard aviodance, and systems management. External world factors influencing the operation of the STOL aircraft include each airport and its geometry, air traffic at each airport, air traffic control equipment and procedures, weather (including winds and visibility), and the flight path between each airport served by the route. The development of the STOL OPS program provides NASA a set of computer programs which can be used for detailed analysis of a STOL aircraft and its avionics and permit establishment of system requirements as a function of airline mission performance goals

Double-Spin Transverse Asymmetries in Drell-Yan Processes

We calculate the double-spin transverse asymmetries for the Drell-Yan lepton pair production in p-p and p-anti p collisions. We assume the transverse and the longitudinal polarization densities to be equal at a very small scale, as it is suggested by confinement model results. Using a global fit for the longitudinal distributions, we find transverse asymmetries of order of 10^-2 at most, in the accessible kinematic regions.Comment: 8 pages, REVTeX, 6 figures included as file figures.tar.g

Hybrid stars with the color dielectric and the MIT bag models

We study the hadron-quark phase transition in the interior of neutron stars (NS). For the hadronic sector, we use a microscopic equation of state (EOS) involving nucleons and hyperons derived within the Brueckner-Bethe-Goldstone many-body theory, with realistic two-body and three-body forces. For the description of quark matter, we employ both the MIT bag model with a density dependent bag constant, and the color dielectric model. We calculate the structure of NS interiors with the EOS comprising both phases, and we find that the NS maximum masses are never larger than 1.7 solar masses, no matter the model chosen for describing the pure quark phase.Comment: 11 pages, 5 figures, submitted to Phys. Rev.

Condensation in ideal Fermi gases

I investigate the possibility of condensation in ideal Fermi systems of general single particle density of states. For this I calculate the probability $w_{N_0}$ of having exactly $N_0$ particles in the condensate and analyze its maxima. The existence of such maxima at macroscopic values of $N_0$ indicates a condensate. An interesting situation occurs for example in 1D systems, where $w_{N_0}$ may have two maxima. One is at $N_0=0$ and another one may exist at finite $N_0$ (for temperatures bellow a certain condensation temperature). This suggests the existence of a first order phase transition. % The calculation of $w_{N_0}$ allows for the exploration of ensemble equivalence of Fermi systems from a new perspective.Comment: 8 pages with 1 figure. Will appear in J. Phys. A: Math. Gen. Changes (minor): I updated Ref. [9] and its citation in the text. I introduced citation for figure 1 in the tex

Effects of color superconductivity on the structure and formation of compact stars

We show that if color superconducting quark matter forms in hybrid or quark stars it is possible to satisfy most of recent observational boundaries on masses and radii of compact stellar objects. An energy of the order of $10^{53}$ erg is released in the conversion from a (metastable) hadronic star into a (stable) hybrid or quark star in presence of a color superconducting phase. If the conversion occurs immediately after the deleptonization of the proto-neutron star, the released energy can help Supernovae to explode. If the conversion is delayed the energy released can power a Gamma Ray Burst. A delay between the Supernova and the subsequent Gamma Ray Burst is possible, in agreement with the delay proposed in recent analysis of astrophysical data.Comment: 4 pages, 2 figures. To be published in Phys.Rev.

Nonextensive statistical effects in the hadron to quark-gluon phase transition

We investigate the relativistic equation of state of hadronic matter and quark-gluon plasma at finite temperature and baryon density in the framework of the nonextensive statistical mechanics, characterized by power-law quantum distributions. We study the phase transition from hadronic matter to quark-gluon plasma by requiring the Gibbs conditions on the global conservation of baryon number and electric charge fraction. We show that nonextensive statistical effects play a crucial role in the equation of state and in the formation of mixed phase also for small deviations from the standard Boltzmann-Gibbs statistics.Comment: 13 pages, 10 figure

Surface structure of Quark stars with magnetic fields

We investigate the impact of magnetic fields on the electron distribution in the electrosphere of quark stars. For moderately strong magnetic fields $B\sim 10^{13}$G, quantization effects are generally weak due to the large number density of electrons at surface, but can nevertheless affect the spectral features of quark stars. We outline the main observational characteristics of quark stars as determined by their surface emission, and briefly discuss their formation in explosive events termed Quark-Novae, which may be connected to the $r$-process.Comment: 9 pages, 3 figures. Contribution to the proceedings of the IXth Workshop on High Energy Physics Phenomenology (WHEPP-9), Bhubaneswar, India, 3-14 Jan. 200

Early Blockade of CB1 Receptors Ameliorates Schizophrenia-like Alterations in the Neurodevelopmental MAM Model of Schizophrenia

In agreement with the neurodevelopmental hypothesis of schizophrenia, prenatal exposure of Sprague-Dawley rats to the antimitotic agent methylazoxymethanol acetate (MAM) at gestational day 17 produces long-lasting behavioral alterations such as social withdrawal and cognitive impairment in adulthood, mimicking a schizophrenia-like phenotype. These abnormalities were preceded at neonatal age both by the delayed appearance of neonatal reflexes, an index of impaired brain maturation, and by higher 2-arachidonoylglycerol (2-AG) brain levels. Schizophrenia-like deficits were reversed by early treatment [from postnatal day (PND) 2 to PND 8] with the CB1 antagonist/inverse agonist AM251 (0.5 mg/kg/day). By contrast, early CB1 blockade affected the behavioral performance of control rats which was paralleled by enhanced 2-AG content in the prefrontal cortex (PFC). These results suggest that prenatal MAM insult leads to premorbid anomalies at neonatal age via altered tone of the endocannabinoid system, which may be considered as an early marker preceding the development of schizophrenia-like alterations in adulthood

Spatial distribution of demersal fishery resources, environmental factors and fishing activities in GSA 15 (Malta Island)

The FAO–MedSudMed Regional Project has promoted research on the improvement of knowledge on fishery ecosystems, with a view to the sustainable management of living marine resources in the central Mediterranean (Straits of Sicily). A pilot study focused on the waters around the Maltese Islands (GSA 15), with the aim of providing a comprehensive overview of the spatial distribution of the different life stages of exploitable demersal fishes in relation to the type and distribution of fishing, as well as to the oceanographic factors characteristic of the area of study. Critical zones for their role in the ecology of the main demersal fishery target species were investigated using species abundance data disaggregated by life stage. Spatial analysis and the application of GIS techniques allowed the identification of preferred habitats (e.g. nursery, feeding and spawning areas) for Merluccius merluccius, Mullus barbatus, Parapenaeus longirostris, Raja clavata and Raja miraletus. The impact of fishing on these species was assessed, particularly in terms of fish assemblages. The transport paths of early life stages were also hypothesized on the basis of oceanographic factors typical of the area. The results revealed that the spatial distribution of the main fishery resources overlaps the limits of the current GSAs. The analysis of oceanographic factors showed that some fishery resources are sustained by young individuals transported from adjacent GSAs. The results also demonstrated that the spatial distribution of the main demersal fishery resources in the Mediterranean GSA 15 straddle other GSAs, in particular as concerns nursery and spawning areas, indicating that some fishery resources are shared. This implies that harmonized fishery management should be applied over a larger area than is implied by the GSA concept. Finally, the study showed how data provided by different methods could be integrated to enhance the available scientific information in a data-limited situation.peer-reviewe