Multi-Conjugate Adaptive Optics Simulator for the Thirty Meter Telescope: Design, Implementation, and Results

We present a multi-conjugate adaptive optics (MCAO) system simulator bench, HeNOS (Herzberg NFIRAOS Optical Simulator). HeNOS is developed to validate the performance of the MCAO system for the Thirty Meter Telescope, as well as to demonstrate techniques critical for future AO developments. In this paper, we focus on describing the derivations of parameters that scale the 30-m telescope AO system down to a bench experiment and explain how these parameters are practically implemented on an optical bench. While referring other papers for details of AO technique developments using HeNOS, we introduce the functionality of HeNOS, in particular, three different single-conjugate AO modes that HeNOS currently offers: a laser guide star AO with a Shack-Hartmann wavefront sensor, a natural guide star AO with a pyramid wavefront sensor, and a laser guide star AO with a sodium spot elongation on the Shack-Hartmann corrected by a truth wavefront sensing on a natural guide star. Laser tomography AO and ultimate MCAO are being prepared to be implemented in the near future

Influence of Materials and Packaging Solutions on Thermal Behaviour of Power Modules

Nowadays, designing ever more efficient power modules requires complex materials and more innovative methodologies. To significantly reduce the lead time of the devices and decrease the costs, especially during the prototyping and the testing phases, a Finite Element Analysis (FEA) can be the simplest way to deal with a matrix of parameters to be studied on a single setup. In this work, a thermal characterization is addressed to a stationary simulation using the COMSOL Multiphysics® software, coupling the Heat Transfer Module and the CFD Module. The study is applied to two types of power modules with different technologies, one with Direct Bonded Copper (DBC) substrate and the other one with Insulated Metal Substrate (IMS). An experimental phase follows in order to test the most performing module. A DBC module is composed by (bottom-up) a substrate (copper base, an alumina insulating layer, copper top layer with a specific electrical layout), soldering layers, the dice, the metallic pins, a covering insulating gel and an external protective box. The IMS modules are equal, except for the substrate made up by (bottom-up) a metal base (copper or aluminium), a polymer with ceramic fillers as insulating layer and a copper top layer with the same electrical layout of DBC. The experimental setup used to test real devices is composed by an aluminium water heatsink with a macroscopical copper plate on the top, separated by a thermal grease layer. The device is then mounted on the copper plate with a defined thermal grease layer in between. The geometry considered in the simulation reproduces accurately this experimental setup. The Heat Transfer Module is set to dissipate about 110 W per die. Air natural convection is neglected since it contributes only marginally to the exchange process. This has been assessed with a specific simulation that allows to fix the total insulating condition on the external boundaries, so that only conductive phenomena are considered at this point. The CFD Module is responsible of the water flux entering the heatsink, while the Multiphysics captures the non-isothermal behaviour of the fluid as it flows inside the heatsink. The mesh incorporates different element sizes, depending on the layers thickness. As a result, the FEA solution, provided by COMSOL Multiphysics®, is mostly in accordance with the experimental data. For DBC module, also the packaging is investigated. Different solutions, such as Vacuum Potting Gel (VPG), are applied to the standard module, analysing thermal resistance and heat dissipation. As an example, the VPG solution consists in filling a protective plastic case with a silicone dielectric gel. The layers disposition is precisely the one described in the DBC section above. The modules are imported in the software and placed upon the testing setup already in use for the previous part. The simulations return interesting insight in the thermal behaviour of the modules

Mild inflammatory profile without gliosis in the c-rel deficient mouse modeling a late-onset parkinsonism

The impact of neuroinflammation and microglial activation to Parkinson’s disease (PD) progression is still debated. Post-mortem analysis of PD brains has shown that neuroinflammation and microgliosis are key features of end-stage disease. However, microglia neuroimaging studies and evaluation of cerebrospinal fluid (CSF) cytokines in PD patients at earlier stages do not support the occurrence of a pronounced neuroinflammatory process. PD animal models recapitulating the motor and non-motor features of the disease, and the slow and progressive neuropathology, can be of great advantage in understanding whether and how neuroinflammation associates with the onset of symptoms and neuronal loss. We recently described that 18-month-old NF-κB/c-Rel deficient mice (c-rel−/−) develop a spontaneous late-onset PD-like phenotype encompassing L-DOPA-responsive motor impairment, nigrostriatal neuron degeneration, α-synuclein and iron accumulation. To assess whether inflammation and microglial activation accompany the onset and the progression of PD-like pathology, we investigated the expression of cytokines (interleukin 1 beta (Il1b), interleukin 6 (Il6)) and microglial/macrophage activation markers (Fc gamma receptor III (Fcgr3), mannose receptor 1 (Mrc1), chitinase-like 3 (Ym1), arginase 1 (Arg 1), triggering receptor expressed on myeloid cells 2 (Trem2)), together with microglial ionized calcium binding adapter molecule 1 (Iba1) and astrocyte glial fibrillary acidic protein (GFAP) immunolabeling, in the substantia nigra (SN) of c-rel−/− mice, at premotor (4- and 13-month-old) and motor phases (18-month-old). By quantitative real-time RT-PCR we found increased M2c microglial/macrophage markers expression (Mrc1 and Arg1) in 4-month-old c-rel−/− mice. M2-type transcription dropped down in 13-month-old c-rel−/− mice. At this age, the pro-inflammatory Il1b, but not Il6 or the microglia-macrophage M1-polarization marker Fcgr3/CD16, increased when compared to wild-type (wt). Furthermore, no significant variation in the transcription of inflammatory and microglial/macrophage activation genes was present in 18-month-old c-rel−/− mice, that display motor dysfunctions and dopaminergic neuronal loss. Immunofluorescence analysis of Iba1-positive cells in the SN revealed no sign of overt microglial activation in c-rel−/− mice at all the time-points. MRC1-Iba1-positive cells were identified as non-parenchymal macrophages in 4-month-old c-rel−/− mice. Finally, no sign of astrogliosis was detected in the SN of the diverse animal groups. In conclusion, this study supports the presence of a mild inflammatory profile without evident signs of gliosis in c-rel−/− mice up to 18 months of age. It suggests that symptomatic PD-like phenotype can develop in the absence of concomitant severe inflammatory process

The monumental submerged Punic harbour of Malfatano and associated Piscinnì quarries: sea level changes and geoarchaeological approach

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NFIRAOS First Facility AO System for the Thirty Meter Telescope

NFIRAOS, the Thirty Meter Telescope's first adaptive optics system is an order 60x60 Multi-Conjugate AO system with two deformable mirrors. Although most observing will use 6 laser guide stars, it also has an NGS-only mode. Uniquely, NFIRAOS is cooled to -30 C to reduce thermal background. NFIRAOS delivers a 2-arcminute beam to three client instruments, and relies on up to three IR WFSs in each instrument. We present recent work including: robust automated acquisition on these IR WFSs; trade-off studies for a common-size of deformable mirror; real-time computing architectures; simplified designs for high-order NGS-mode wavefront sensing; modest upgrade concepts for high-contrast imaging.Comment: ..submitted to SPIE 9148 Astronomical Telescopes and Instrumentation - Adaptive Optics Systems IV (2014

Effects of warmer and drier climate conditions on plant composition and biomass production in a Mediterranean shrubland community

The last IPCC report predicts warmer and drier conditions for the future European climate and the Mediterranean basin could be highly sensible to future climatic change. In order to investigate how the forecast more stressing factors could affect Mediterranean shrubland ecosystems, an appropriate manipulation of the microclimate was carried out in an area covered by Mediterranean maquis aimed at extending the drought period and increasing the night-time temperature. Soil cover, plant growth, litterfall, leaf water status, and leaf nutritional status were monitored over three growing seasons. The manipulation altered the microclimate according to common scenarios, increasing mean annual night-time air temperature by about 1 °C and mean annual temperature by about 0.5 °C, and decreasing precipitation between 6-46% of the total rainfall during the growing seasons. A general increase of vegetation cover was observed in the whole community during the three years of experimentation. This positive temporal pattern was mainly observed in control and warming treatment, whereas in the drought treatment it was less evident. At species-specific level, a clear negative effect of drought treatment was observed for C. monspeliensis percentage cover. Shoot elongation was not significantly affected by the warming treatment. A significant negative effect of drought treatment was noticed in the 2001-2002 and 2002-2003 growing seasons. An increase of N and P concentrations in the drought treatment in Cistus was observed and it can be explained by the reduced shoot growth induced by the water shortage that we had observed in the same treatment. The absence of a concentration effect on the other two species could be the signal of the different behaviour with regard to a drier climate, and therefore could be a symptom of future change in species composition. We underline the need of longterm observation, because of the different responses of plants in the short and long- term conditions

Mesenchymal stem/stromal cells as a delivery platform in cell and gene therapies

Regenerative medicine relying on cell and gene therapies is one of the most promising approaches to repair tissues. Multipotent mesenchymal stem/stromal cells (MSC), a population of progenitors committing into mesoderm lineages, are progressively demonstrating therapeutic capabilities far beyond their differentiation capacities. The mechanisms by which MSC exert these actions include the release of biomolecules with anti-inflammatory, immunomodulating, anti-fibrogenic, and trophic functions. While we expect the spectra of these molecules with a therapeutic profile to progressively expand, several human pathological conditions have begun to benefit from these biomolecule-delivering properties. In addition, MSC have also been proposed to vehicle genes capable of further empowering these functions. This review deals with the therapeutic properties of MSC, focusing on their ability to secrete naturally produced or gene-induced factors that can be used in the treatment of kidney, lung, heart, liver, pancreas, nervous system, and skeletal diseases. We specifically focus on the different modalities by which MSC can exert these functions. We aim to provide an updated understanding of these paracrine mechanisms as a prerequisite to broadening the therapeutic potential and clinical impact of MSC