14,419 research outputs found
Output Regulation for Systems on Matrix Lie-group
This paper deals with the problem of output regulation for systems defined on
matrix Lie-Groups. Reference trajectories to be tracked are supposed to be
generated by an exosystem, defined on the same Lie-Group of the controlled
system, and only partial relative error measurements are supposed to be
available. These measurements are assumed to be invariant and associated to a
group action on a homogeneous space of the state space. In the spirit of the
internal model principle the proposed control structure embeds a copy of the
exosystem kinematic. This control problem is motivated by many real
applications fields in aerospace, robotics, projective geometry, to name a few,
in which systems are defined on matrix Lie-groups and references in the
associated homogenous spaces
Molecular characterization of human CD4+ IL-10-producing regulatory cells
Previous studies in the group led to the identification of CD4+FOXP3- cells with regulatory functions in human blood that coproduce IL-10 and IFN-gamma. These cells do not belong to the Treg cell lineage since they are Foxp3- but they show some similarities with Th1 cells since they express CCR5, T-bet and produce high levels of IFN-gamma. Thus, they share relevant characteristics with both T regulatory type I cells (Tr1) and Th1 cells and we called them Th1-10 cells.
In this study we presented a molecular characterization of Th1-10 cells that includes a gene expression and a microRNA profiling and performed functional studies to assess Th1-10 cells regulatory properties. We demonstrated that Th1-10 cells have a high regulatory potential being able to block the proliferation of activated CD4 naïve T cells to a similar extent as conventional Treg cells, and that this suppression capacity is at least partially mediated by secreted IL10.
We showed also that Th1-10 cells are closely related to Th1 effector memory cells and express genes involved in cytotoxicity. In particular, they express the transcription factor EOMES and the cytotoxic effector molecules GZMA and GZMK, and they release cytotoxic granules upon stimulation. Moreover, we found that Eomes regulates cytotoxic functions in CD4+ T cells.
We demonstrated that miR-92a, selectively downregulated in Th1-10 cells, directly targets the 3’UTR of EOMES.and this finding identifies miR-92a as a possible mediator of Th1-10 cytotoxicity.
Th1-10 cells retain some proliferative capacity when sorted ex vivo and activated in vitro via their TCR, and this effect is markedly enhanced by IL-15, which also had a pro-survival effect on Th-10 cells.
Thus, in contrast to conventional cytotoxic T cells, Th1-10 cells have cytotoxic and regulatory functions and are not terminally differentiated, since they retain proliferative capacity
Atmospheric monitoring in the mm and sub-mm bands for cosmological observations: CASPER2
Cosmological observations from ground at millimetre and sub-millimetre
wavelengths are affected by atmospheric absorption and consequent emission. The
low and high frequency (sky noise) fluctuations of atmospheric performance
imply careful observational strategies and/or instrument technical solutions.
Measurements of atmospheric emission spectra are necessary for accurate
calibration procedures as well as for site testing statistics. CASPER2, an
instrument to explore the 90-450 GHz (3-15 1/cm) spectral region, was developed
and verified its operation in the Alps. A Martin-Puplett Interferometer (MPI)
operates comparing sky radiation, coming from a field of view (fov) of 28
arcminutes (FWHM) collected by a 62-cm in diameter Pressman-Camichel telescope,
with a reference source. The two output ports of the interferometer are
detected by two bolometers cooled down to 300 mK inside a wet cryostat. Three
different and complementary interferometric techniques can be performed with
CASPER2: Amplitude Modulation (AM), Fast-Scan (FS) and Phase Modulation (PM).
An altazimuthal mount allows the sky pointing, possibly co-alligned to the
optical axis of the 2.6-m in diameter telescope of MITO (Millimetre and
Infrared Testagrigia Observatory, Italy). Optimal timescale to average acquired
spectra is inferred by Allan variance analysis at 5 fiducial frequencies. We
present the motivation for and design of the atmospheric spectrometer CASPER2.
The adopted procedure to calibrate the instrument and preliminary performance
of the instrument are described. Instrument capabilities were checked during
the summer observational campaign at MITO in July 2010 by measuring atmospheric
emission spectra with the three different procedures.Comment: 11 pages, 9 figures, 2 tables, Accepted for publication in MNRA
Reliability and use of Copenhagen Burnout Inventory in italian sample of university professors
Academics often have to face with burnout syndrome at work. This cross-sectional study evaluates the reliability of the Italian version of the Copenhagen Burnout Inventory (CBI) in a sample of Academics of Sapienza University of Faculty of Medicine and Pharmacy, through an online questionnaire composed of the CBI, SF12 Health Survey, and Positivity Scale. Univariate, bivariate, multivariate analyses, and Cronbach α coefficients of CBI were performed. Ninety-five participants completed the questionnaire (response rate 85%). Cronbach’s α of the three domains were high (0.892, 0.868, and 0.836). Women, younger and part time professors reported higher score in personal (p = 0.025; 0.060) and work burnout. In multivariate analysis decreasing age (β = −0.263; p = 0.001); being a professor in environmental technicians (β = −0.120; p = 0.098); and low mental (β = −0.263; p = 0.020), physical (β = −0.319; p ≤ 0.001) and positivity scores (β = −0.237; p = 0.031) predict significantly higher personal burnout. Low physical (β = −0.346; p < 0.001) and mental (β = − 0.249; p = 0.013) positivity (β = −0.345; p = 0.001) scores; fewer years of work (β = −0.269; p ≤ 0.001); and being a medical or nursing professor (β = 0.169; p = 0.016) predicts high work burnout. Low MCS predicts a high level of student burnout. Results suggest that the Italian version of the CBI is a reliable instrument. Further research should focus on the prevalence of burnout in academics
Excessive increase in left ventricular mass identifies hypertensive subjects with clustered geometric and functional abnormalities
Female preference and predation risk models can explain the maintenance of a Fallow deer (<i>Dama dama</i>) lek and its ‘handy’ location
We tested the predictions of three models (female preference; hotspot; predator avoidance) on lek formation in the fallow deer population of San Rossore, Tuscany. We collected behavioural observations in two leks and radiotracking data on 67 deer over 7 years. Two deer sub-populations were present in the northern and southern sides of the area, respectively, the two sectors being delimited by a river and including one lek each. Predictions were tested for one lek (SG), located in the south-side where we set up our 7-year radiotracking program. Data from a second lek (FO, north-side) were used to test those predictions which imply the occurrence of multiple leks in the same population. We showed that the majority of females made one single visit to one lek, only during the rut. The lek was located outside areas of higher female traffic and home range overlap, and females increased home range sizes during the rut to reach it. Twilight routes of females never crossed the lek; instead, females walked atypical routes and at a faster pace to reach the lek and mate. The distance between the two leks was higher than the average diameter of female home ranges, and only one lek was present within female home ranges. Males reached the lek one month before the arrival of females, corroborating that lekking is a female-initiated process (females moving towards large clumped male aggregations) rather than a male-initiated process (males moving towards female hotspots). Our results supported the female preference model, and rejected the predictions of the hotspot model. Also, leks were located far from areas with higher predation risk, supporting the predator avoidance model. The position of lek SG resulted ‘handy’ at the sub-population level because of the optimal trade-off between travel costs for females to reach it and avoidance of human predators
Glucose-6-phosphate dehydrogenase plays a central role in the response of tomato (Solanum lycopersicum) plants to short and long-term drought
The present study was undertaken to investigate the expression, occurrence and activity of glucose 6
phosphate dehydrogenase (G6PDH e EC 1.1.1.49), the key-enzyme of the Oxidative Pentose Phosphate
Pathway (OPPP), in tomato plants (Solanum lycopersicum cv. Red Setter) exposed to short- and long-term
drought stress.
For the first time, drought effects have been evaluated in plants under different growth conditions: in
hydroponic laboratory system, and in greenhouse pots under controlled conditions; and in open field, in
order to evaluate drought response in a representative agricultural environment.
Interestingly, changes observed appear strictly associated to the induction of well known stress
response mechanisms, such as the increase of proline synthesis, accumulation of chaperone Hsp70, and
ascorbate peroxidase.
Results show significant increase in total activity of G6PDH, and specifically in expression and
occurrence of cytosolic isoform (cy-G6PDH) in plants grown in any cultivation system upon drought.
Intriguingly, the results clearly suggest that abscissic acid (ABA) pathway and signaling cascade
(protein phosphatase 2C e PP2C) could be strictly related to increased G6PDH expression, occurrence and
activities.
We hypothesized for G6PDH a specific role as one of the main reductants’ suppliers to counteract the
effects of drought stress, in the light of converging evidences given by young and adult tomato plants
under stress of different duration and intensity
Not only a problem of fatigue and sleepiness: Changes in psychomotor performance in Italian nurses across 8-h rapidly rotating shifts
Although many studies have detailed the consequences of shift work in nurses concerning health, fatigue, sleepiness, or medical errors, no study has been carried out trying to disentangle the contribution of sleepiness and fatigue associated to shift work from the attentional performance. The aim of this pilot study is (A) to investigate the effects of an 8-h rapidly rotating shift on fatigue and sleepiness among staff nurses and (B) how these factors affect their psychomotor performance. Fourteen nurses were selected for a within-subject cross-sectional study according to this sequence of shifts: morning–afternoon–night, which were compared as function of tiredness, sleepiness, and performance at the Psychomotor Vigilance Task (PVT). Subsequently, a within-subject Analysis of Covariance (ANCOVA) evaluated if the observed differences between shifts persist when the contribution of sleepiness is controlled. Our results clearly indicate that night shifts are associated with significant greater sleepiness and tiredness, and worsened performance at the PVT. As hypothesized, ANCOVA showed that these differences disappear when the contribution of sleepiness is controlled. Results point to a lower psychomotor performance in night compared to day shifts that depends on sleepiness. Hence, interventions to minimize the consequences of the night shift should consider a reduction of sleepiness
- …
