Russia and The West in the Mediterranean Perspectives for the 1970\u27s

The Mediterranean Sea has always played an important role in European strategy. Since the days of Homer, it has provided an invaluable highway for the movement of goods, ideas, and invading armies. Although the sea itself has remained essentially unchanged over the centuries, it has assumed a variety of forms in men\u27s eyes, depending on their vantage point and ambitions

The Soviet Presence in the Mediterranean: A Short History

The presence of a significant Soviet naval force in the Mediterranean seems to represent a new element in international relations

LSST: from Science Drivers to Reference Design and Anticipated Data Products

(Abridged) We describe here the most ambitious survey currently planned in the optical, the Large Synoptic Survey Telescope (LSST). A vast array of science will be enabled by a single wide-deep-fast sky survey, and LSST will have unique survey capability in the faint time domain. The LSST design is driven by four main science themes: probing dark energy and dark matter, taking an inventory of the Solar System, exploring the transient optical sky, and mapping the Milky Way. LSST will be a wide-field ground-based system sited at Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m effective) primary mirror, a 9.6 deg$^2$ field of view, and a 3.2 Gigapixel camera. The standard observing sequence will consist of pairs of 15-second exposures in a given field, with two such visits in each pointing in a given night. With these repeats, the LSST system is capable of imaging about 10,000 square degrees of sky in a single filter in three nights. The typical 5$\sigma$ point-source depth in a single visit in $r$ will be $\sim 24.5$ (AB). The project is in the construction phase and will begin regular survey operations by 2022. The survey area will be contained within 30,000 deg$^2$ with $\delta<+34.5^\circ$, and will be imaged multiple times in six bands, $ugrizy$, covering the wavelength range 320--1050 nm. About 90\% of the observing time will be devoted to a deep-wide-fast survey mode which will uniformly observe a 18,000 deg$^2$ region about 800 times (summed over all six bands) during the anticipated 10 years of operations, and yield a coadded map to $r\sim27.5$. The remaining 10\% of the observing time will be allocated to projects such as a Very Deep and Fast time domain survey. The goal is to make LSST data products, including a relational database of about 32 trillion observations of 40 billion objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures available from https://www.lsst.org/overvie

Spatial Analysis of Expression Patterns Predicts Genetic Interactions at the Mid-Hindbrain Boundary

The isthmic organizer mediating differentiation of mid- and hindbrain during vertebrate development is characterized by a well-defined pattern of locally restricted gene expression domains around the mid-hindbrain boundary (MHB). This pattern is established and maintained by a regulatory network between several transcription and secreted factors that is not yet understood in full detail. In this contribution we show that a Boolean analysis of the characteristic spatial gene expression patterns at the murine MHB reveals key regulatory interactions in this network. Our analysis employs techniques from computational logic for the minimization of Boolean functions. This approach allows us to predict also the interplay of the various regulatory interactions. In particular, we predict a maintaining, rather than inducing, effect of Fgf8 on Wnt1 expression, an issue that remained unclear from published data. Using mouse anterior neural plate/tube explant cultures, we provide experimental evidence that Fgf8 in fact only maintains but does not induce ectopic Wnt1 expression in these explants. In combination with previously validated interactions, this finding allows for the construction of a regulatory network between key transcription and secreted factors at the MHB. Analyses of Boolean, differential equation and reaction-diffusion models of this network confirm that it is indeed able to explain the stable maintenance of the MHB as well as time-courses of expression patterns both under wild-type and various knock-out conditions. In conclusion, we demonstrate that similar to temporal also spatial expression patterns can be used to gain information about the structure of regulatory networks. We show, in particular, that the spatial gene expression patterns around the MHB help us to understand the maintenance of this boundary on a systems level

La révolution iranienne et les grandes puissances

Sick Gary. La révolution iranienne et les grandes puissances. In: Politique étrangère, n°2 - 1987 - 52ᵉannée. pp. 339-355

Iran thirty years on

Gary Sick; Michael Axworth

MPP +-induced pathophysiology demonstrates advantages of neurotoxicology studies in brain slices

Since MPTP and its metabolite MPP + produce nigrostriatal lesions and symptoms similar to Parkinson's disease, recent studies have aimed toward defining their selectivity and neurotoxic mechanisms. In mitochondria in vitro, MPP + blocked electron transport and decreased oxygen consumption. However, these effects were not selective to striatal mitochondria or even to mitochondria from brain, they required concentrations of MPP + much greater than those found in vivo, and physiological actions could not be related to intramitochondrial changes. Lower doses of MPP + did produce highly selective degeneration of dopaminergic (DA) neurons in cell cultures. We report here that MPP + provoked large (80%) oxidations of cytochrome b and large K o + increments (approximately 30 mM) in rat striatal slices. These effects were slowed by mazindol, which inhibits DA uptake, and were markedly attenuated in rat hippocampal slices which have little DA input. Since DA terminals comprise only 2–4% of the striatal mass, the large MPP +-induced changes suggest that while MPP + neurotoxicity in brain requires the presence of functioning DA terminals, effects are not confined to these terminals. Such studies illustrate the complexity of MPP + neurotoxicity and demonstrate the importance of investigations in models such as brain slices with an extracellular space and intercellular relationships as in intact brain