Integrated Calendar

The Local Group galaxy M32 is a compact elliptical galaxy, satellite of M31. Although a low-luminosity galaxy, M32 is the nearest system with structural properties reminiscent of giant ellipticals. Given its proximity, M32 provides a unique window on the stellar composition of elliptical galaxies since it can be studied by both its integrated spectrum and the photometry of its resolved stars. To date, however, there has not been a consistent comparison between predictions from the spectroscopic
analysis of its integrated light and its resolved stellar content. Moreover, the SFH of M32 is still a matter of debate. In this talk, I will focus on the resolved stellar populations of M32 at 2 arcmin from its center. Very high resolution HST observations of two fields near M32 were used to construct and analyze deep color-magnitude diagrams (CMDs). These CMDs reveal the different stellar populations present in M32 and allow us to extract information about the stellar ages and
metallicities distributions in this galaxy, from both qualitative and
quantitative analyses. I will also show the results from the study of RR
Lyrae variable stars in the same fields. I will discuss the formation of
M32 based on our results and conclude by discussing some follow up studies
based on this work.

In the past few decades, large amount of knowledge about the solar corona and solar wind has been gathered by both in-situ and remote measurements all over the solar system. However, this knowledge is not fully considered in stellar astrophysics. In particular, mass loss of stars to their stellar winds are traditionally related to their level of activity and their X-ray flux. In the talk, I will overview the known properties of the solar wind and will show how the solar mass flux and the solar X-ray flux do not seem to correlate at all. I will also discuss the possible reason for this finding.

Implantable medical devices can provide life-giving help to many systems in the body. When made of a biodegradable polymer, such devices degrade with time and the end products are nontoxic. These devices can remain intact in the body for a predicted period of time – from weeks to years – and then degrade without the need for surgical removal. Active implants are drug or protein-eluting implants that induce healing effects, in addition to their regular task, such as support. This effect is achieved by controlled release of bioactive agents to the surrounding tissue. Examples for these active implants are wound dressings with antibiotic controlled release, stents with controlled release of antiproliferative agents, and scaffolds for tissue regeneration with controlled release of growth factors. We have developed and studied biodegradable active implants, based on drug-eluting fibers and drug-eluting films. The effects of the kinetic and thermodynamic parameters in the preparation process on the microstructure and on the resulting properties (drug release profile, mechanical and physical properties etc.) were investigated. Biocompatibility and other biological functions, such as bacterial inhibition were also studied. The results of our studies thus have great medical relevance and are aimed to provide solutions to basic needs in the fields of medical implants and tissue regeneration.

An interesting paradox exists in the lung: a stable lipid interface must be maintained while individual lipids are rapidly exchanged and actively sorted. Surfactant protein B, SP-B, is critical to lung function, particularly for trafficking of lipids within pulmonary surfactant and altering lipid properties at the air-water interface. The N- and C-terminal segments of SP-B and synthetic analogs retain many of the properties of full-length SP-B and have proven suc¬cessful in treat¬ing respiratory distress. We are developing and applying ssNMR and EPR techniques to study the interplay between peptide partitioning, lipid dynamics, pep¬tide secondary structure and dynamics, lipid polymorphisms, and temperature, pro¬viding important in¬sights into lung sur¬factant function and more generally the enthalpic and entropic con¬tribu¬tions underlying amphipathic peptides interactions with and influence on phos¬pholipid assemblies. Our method¬ologies and samples pre¬sent unique challenges due to the thermal properities of the samples and the need for strong RF excitation fields. Using static and MAS ssNMR experi¬ments coupled with EPR measurements and molecular dynamics simulations, we are de¬veloping a molecular level understanding of the varied structure and function of pulmonary surfactant peptides and their effects on lipid dynamics and speci¬ation. Our results highlight lipid-dependent structural plasticity and unusual amphipathic helical secondary struc-ture may be important to surfactant peptide functions. While both the C-terminal and N-terminal segments of SP-B are amphipathic helices, each displays unique properties which are complementary, explaining the success of chimeric constructs of these peptides in treating respiratory distress. Based on our studies, an understanding of the varying roles of the lung surfactant peptides is emerging.

The Japanese Hayabusa spacecraft returned to Earth on 13 June 2010 carrying within it a precious but invisible cargo - 1534 particles of dust from the surface of the asteroid Itokawa, which the spacecraft visited in 2005. These particles, up to 180 micrometer in size, are the first material ever fetched from an asteroid and returned to Earth for laboratory analysis. In the 26 August 2011 Science, six Reports, plus related news and commentary, discuss the mineralogy, petrography, chemistry, and noble gas and oxygen-isotope compositions of the Itokawa particles, which provide insights into the evolution of the solar system.