Isolation, Identification, Modification, and Biological Analysis of extracts of A. Mexicana

Argemone mexicana is a member of the Papaveraceae family of plants that has been used for centuries in traditional medicine by indigenous communities in Mexico and the United States. Through a collaborative project, we have explored separation of key components of the seeds and leaves of this plant to isolate the source of their biological activity. We have already identified two key molecules which give this plant anti-microbial properties against the gram-positive bacteria. Furthermore, we have chemically modified one of these molecules to observe variations on activity. We hope this leads to the discovery of new antibiotic drugs

Interakcija, sukreacija i participacija u literaturi o javnim medijskim servisima, politici i strategiji: komparativna analiza slučajeva flamanskog dijela Belgije, Nizozemske, Francuske i Ujedinjenog Kraljevstva

The article critically evaluates whether there is a (mis)match between ideas on audience involvement in public service media (PSM) theory and the translation thereof in public broadcasters’ policy and strategy documents. The literature section theoretically frames this discussion, first, discussing five objectives of PSM and audience involvement. Subsequently, it studies how the BBC (UK), France Télévisions (France), VRT (Flanders), and NPO (the Netherlands) have to (policy) and intend to (strategy) involve their audiences. These cases have been selected with an eye on including both better-funded (BBC, FTV) and smaller public broadcasters (VRT, NPO), as well as different media systems. For the analysis, the method of goal-means tree analysis is adopted, a type of qualitative document analysis that can be deployed to uncover goal-means relationships in policy and strategy texts. The main argument is that, rather than a mismatch, some of the questionable, normative assumptions made in theories concerning audience involvement and PSM are also present in the PSM policy and strategy texts.Rad kritički evaluira postoji li (ne)podudaranje između teorije javnog medijskog servisa i njegove politike i strateških dokumenata kada je riječ o idejama uključivanja medijskih publika u javni medijski servis. Najprije se teorijski nastoji uokviriti ova rasprava, tako da se razmatra pet zadaća uključivanja medijskih publika u javni medijski servis. Potom se istražuje kako BBC (Ujedinjeno Kraljevstvo), France Télévisions (Francuska), VRT (Flandrija, Belgija) i NPO (Nizozemska) trebaju (politika) i namjeravaju (strategija) uključiti svoje medijske publike. Odabrani slučajevi daju uvid u bolje financirane (BBC, FTV) i manje javne medijske servise (VRT, NPO), kao i u različite medijske sustave. Upotrijebljena je metoda goal-means tree analiza, tip kvalitativne analize dokumenata kojoj je svrha otkrivanje odnosa između cilja i sredstava u politici i strateškim tekstovima. Glavni je argument da je ovdje prije riječ o nekim upitnim, normativnim pretpostavkama iz teorije o javnom medijskom servisu i uključenosti publike, koje su prenesene i u tekstove o politici i strategiji javnog medijskog servisa, a ne o nepodudaranju između teorije, politike i strategije javnog medijskog servisa

A Microscopic Energy- and Density-Dependent Effective Interaction and its Test by Nucleus-Nucleus Scattering

An effective nucleon-nucleon interaction calculated in nuclear matter from the Bonn potential has been parametrized in terms of a local density- and energy-dependent two-body interaction. This allows to calculate the real part of the nucleus-nucleus scattering potential and to test this effective interaction over a wide region of densities ($\rho \leq 3\rho_0$) produced dynamically in scattering experiments. Comparing our calculations with empirical potentials extracted from data on light and heavy ion scattering by model-unrestricted analysis methods, we find quantitative agreement with the exception of proton scattering. The failure in this case may be traced back to the properties of the effective interaction at low densities, for which the nuclear matter results are not reliable. The success of the interaction at high overlap densities confirms the empirical evidence for a soft equation of state for cold nuclear matter.Comment: 8 pages 3 Figures included, to appear in Phys. Lett.

Infrared point source variability between the Spitzer and MSX surveys of the Galactic mid-plane

We present a list of 552 sources with suspected variability, based on a comparison of mid-infrared photometry from the GLIMPSE I and MSX surveys, which were carried out nearly a decade apart. We were careful to address issues such as the difference in resolution and sensitivity between the two surveys, as well as the differences in the spectral responses of the instruments. We selected only sources where the IRAC 8.0 and MSX 8.28 micron fluxes differ by more than a factor of two, in order to minimize contamination from sources where the difference in fluxes at 8 micron is due to a strong 10 micron silicate feature. We present a subset of 40 sources for which additional evidence suggests variability, using 2MASS and MIPSGAL data. Based on a comparison with the variability flags in the IRAS and MSX Point-Source Catalogs we estimate that at least a quarter of the 552 sources, and at least half of the 40 sources are truly variable. In addition, we tentatively confirm the variability of one source using multi-epoch IRAS LRS spectra. We suggest that most of the sources in our list are likely to be Asymptotic Giant Branch stars.Comment: 47 pages, 12 Figures, 3 Tables, accepted for publication in A

Delta Advanced Reusable Transport (DART): An alternative manned spacecraft

Although the current U.S. Space Transportation System (STS) has proven successful in many applications, the truth remains that the space shuttle is not as reliable or economical as was once hoped. In fact, the Augustine Commission on the future of the U.S. Space Program has recommended that the space shuttle only be used on missions directly requiring human capabilities on-orbit and that the shuttle program should eventually be phased out. This poses a great dilemma since the shuttle provides the only current or planned U.S. means for human access to space at the same time that NASA is building toward a permanent manned presence. As a possible solution to this dilemma, it is proposed that the U.S. begin development of an Alternative Manned Spacecraft (AMS). This spacecraft would not only provide follow-on capability for maintaining human space flight, but would also provide redundancy and enhanced capability in the near future. Design requirements for the AMS studied include: (1) capability of launching on one of the current or planned U.S. expendable launch vehicles (baseline McDonnell Douglas Delta II model 7920 expendable booster); (2) application to a wide variety of missions including autonomous operations, space station support, and access to orbits and inclinations beyond those of the space shuttle; (3) low enough costing to fly regularly in augmentation of space shuttle capabilities; (4) production surge capabilities to replace the shuttle if events require it; (5) intact abort capability in all flight regimes since the planned launch vehicles are not man-rated; (6) technology cut-off date of 1990; and (7) initial operational capability in 1995. In addition, the design of the AMS would take advantage of scientific advances made in the 20 years since the space shuttle was first conceived. These advances are in such technologies as composite materials, propulsion systems, avionics, and hypersonics