35 research outputs found
Somatic, but not cognitive-affective, symptoms are associated with reduced heart rate variability in individuals with dysphoria
Background: Somatic, but not cognitive-affective, symptoms of depression have been associated with reduced heart rate variability (HRV), and with poor prognosis in cardiovascular patients. However, factors concomitant with cardiovascular diseases may confound the relationship between somatic symptoms of depression and reduced HRV. Therefore, this study examined whether reduced HRV was differentially associated with cognitive-affective and somatic symptoms of depression in medically healthy individuals with and without dysphoria. Methods: Self-reported cognitive-affective and somatic symptoms as measured with the Beck Depression Inventory-II (BDI-II) questionnaire and time and frequency domain parameters of HRV were collected in 62 medically healthy individuals, of whom 25 with and 37 without dysphoria. Results: Somatic, but not cognitive-affective, symptoms of depression were inversely associated with standard deviation of NN intervals (SDNN) (beta = -0.476, p .24). Conclusions: By showing that the relationship between somatic depressive symptoms and reduced HRV extends to medically healthy individuals with dysphoria, the present findings suggest that this association is independent of factors concomitant with cardiovascular diseases. The present study also suggests that individuals with somatic rather than cognitive-affective subsets of depressive symptoms may be at greater risk for developing cardiovascular diseases
The STRIP instrument of the Large Scale Polarization Explorer: microwave eyes to map the Galactic polarized foregrounds
In this paper we discuss the latest developments of the STRIP instrument of
the "Large Scale Polarization Explorer" (LSPE) experiment. LSPE is a novel
project that combines ground-based (STRIP) and balloon-borne (SWIPE)
polarization measurements of the microwave sky on large angular scales to
attempt a detection of the "B-modes" of the Cosmic Microwave Background
polarization. STRIP will observe approximately 25% of the Northern sky from the
"Observatorio del Teide" in Tenerife, using an array of forty-nine coherent
polarimeters at 43 GHz, coupled to a 1.5 m fully rotating crossed-Dragone
telescope. A second frequency channel with six-elements at 95 GHz will be
exploited as an atmospheric monitor. At present, most of the hardware of the
STRIP instrument has been developed and tested at sub-system level.
System-level characterization, starting in July 2018, will lead STRIP to be
shipped and installed at the observation site within the end of the year. The
on-site verification and calibration of the whole instrument will prepare STRIP
for a 2-years campaign for the observation of the CMB polarization.Comment: 17 pages, 15 figures, proceedings of the SPIE Astronomical Telescopes
+ Instrumentation conference "Millimeter, Submillimeter, and Far-Infrared
Detectors and Instrumentation for Astronomy IX", on June 15th, 2018, Austin
(TX
The Large-Scale Polarization Explorer (LSPE)
The LSPE is a balloon-borne mission aimed at measuring the polarization of
the Cosmic Microwave Background (CMB) at large angular scales, and in
particular to constrain the curl component of CMB polarization (B-modes)
produced by tensor perturbations generated during cosmic inflation, in the very
early universe. Its primary target is to improve the limit on the ratio of
tensor to scalar perturbations amplitudes down to r = 0.03, at 99.7%
confidence. A second target is to produce wide maps of foreground polarization
generated in our Galaxy by synchrotron emission and interstellar dust emission.
These will be important to map Galactic magnetic fields and to study the
properties of ionized gas and of diffuse interstellar dust in our Galaxy. The
mission is optimized for large angular scales, with coarse angular resolution
(around 1.5 degrees FWHM), and wide sky coverage (25% of the sky). The payload
will fly in a circumpolar long duration balloon mission during the polar night.
Using the Earth as a giant solar shield, the instrument will spin in azimuth,
observing a large fraction of the northern sky. The payload will host two
instruments. An array of coherent polarimeters using cryogenic HEMT amplifiers
will survey the sky at 43 and 90 GHz. An array of bolometric polarimeters,
using large throughput multi-mode bolometers and rotating Half Wave Plates
(HWP), will survey the same sky region in three bands at 95, 145 and 245 GHz.
The wide frequency coverage will allow optimal control of the polarized
foregrounds, with comparable angular resolution at all frequencies.Comment: In press. Copyright 2012 Society of Photo-Optical Instrumentation
Engineers. One print or electronic copy may be made for personal use only.
Systematic reproduction and distribution, duplication of any material in this
paper for a fee or for commercial purposes, or modification of the content of
the paper are prohibite
Evolution and alteration of organic material on Ceres, a pathway towards the understanding of complex geological and chemical history of a wet small body
Ceres is the largest object in the Solar System main belt. Clearly, Ceres experienced extensive water-related processes and geochemical differentiation and nowadays it is a body with a complex geological and chemical history. Its surface is characterized by dark materials, phyllosilicates, ammonium-bearing minerals, carbonates, water ice, and salts. In addition to a global presence of carbon bearing chemistry, local concentration of aliphatic organics has been detected by Dawn.
In this context, we have started a series of laboratory spectroscopy measurements targeted to study the physicochemical interactions between organic material and minerals possibly present on Ceres. The goal is to understand the transformations induced on these samples by ultraviolet radiation, neutral atoms, and fast ions, under experimental conditions that simulate the environment of Ceres. The spectroscopic data obtained in laboratory experiments allow, through the comparison with the observations of the VIR spectrometer aboard the Dawn mission, to clarify the nature and origin of organic material identified on Ceres
Photoprocessing of Organic Material on Ceres: Laboratory Studies on Chemical Evolution of the Inner Dwarf Planet
Ceres is the largest object of the Solar System main belt with a complex geological and chemical history, which experienced extensive water related processes and geochemical differentiation. Ceres' surface is characterized by dark materials, phyllosilicates, ammonium-bearing minerals, carbonates, water ice, and salts. In addition to a global presence of carbon-bearing chemistry, local concentration of aliphatic organics has been detected by Dawn mission. The mission, thanks to the data collected by the Italian instrument VIR, showed clear evidence of a high amount of aliphatic organic material on the surface of Ceres. This has raised new questions about the origin and preservation of this material, especially when considering its high estimated abundance. We started a series of laboratory studies on physicochemical evolution of organic material interacting with minerals thought to be present on Ceres. The goal is to understand the transformations induced on these samples by processing with ultraviolet radiation
Photoprocessing of Organic Material on Ceres: Laboratory Studies on Chemical Evolution of a Wet Small Body
We studied the UV irradiation of minerals, water, and organic material mixture deriving clues on the origin and evolution of materials present on Ceres
Techniques to verify the sampling system and flow characteristics of the sensor MicroMED for the ExoMars 2022 Mission
Suspended dust has a prominent role in Martian climatology. Several significant dust related phenomena can be observed at various scales, starting from global dust storms to local dust devils, which have important effects such as the increase of troposphere temperature, the modification of the wind regime and the localized motion of sand at the surface. These phenomena depend on dust grain characteristics such as the size distribution or the chemical and bulk composition. Currently, we do not have direct measurement of the dust properties; the only available information in this regard are derived from spectrometric measurements, optical depth, and albedo coming from instruments aboard satellites and in-situ. Herein, we describe the tests performed on the optical particle counter named MicroMED, designed and built to perform the first ever direct in-situ measurement of suspended dust grains in the Martian atmosphere close to the surface. MicroMED is a dust particle size analyzer which was selected to join the Dust Complex payload aboard the ESA/Roscosmos ExoMars 2022 mission. It has the capability to suck in dust that is suspended in atmosphere and to measure the sizes of single grain. The sensor sucks in the dust grains using a sampling system, guides the grains through ducts and concentrates them in an area illuminated by laser. Detecting the intensity of the light scattered by the grains during the crossing through the illuminated area, it is possible to determinate the size of grain. Here we present the innovative techniques in order to verify the performances in terms of dust suction efficiency of the MicroMED Flight Model, using a prototype called MM1