48 research outputs found
Preliminary error budget analysis of the coronagraphic instrument metis for the solar orbiter ESA mission
METIS, the Multi Element Telescope for Imaging
and Spectroscopy, is the solar coronagraph foreseen for the ESA
Solar Orbiter mission. METIS is conceived to image the solar
corona from a near-Sun orbit in three different spectral bands: in
the HeII EUV narrow band at 30.4 nm, in the HI UV narrow
band at 121.6 nm, and in the polarized visible light band (590 –
650 nm). It also incorporates the capability of multi-slit
spectroscopy of the corona in the UV/EUV range at different
heliocentric heights.
METIS is an externally occulted coronagraph which adopts an
“inverted occulted” configuration. The Inverted external occulter
(IEO) is a small circular aperture at the METIS entrance; the
Sun-disk light is rejected by a spherical mirror M0 through the
same aperture, while the coronal light is collected by two annular
mirrors M1-M2 realizing a Gregorian telescope. To allocate the
spectroscopic part, one portion of the M2 is covered by a grating
(i.e. approximately 1/8 of the solar corona will not be imaged).
This paper presents the error budget analysis for this newconcept
coronagraph configuration, which incorporates 3
different sub-channels: UV and EUV imaging sub-channel, in
which the UV and EUV light paths have in common the detector
and all of the optical elements but a filter, the polarimetric visible
light sub-channel which, after the telescope optics, has a
dedicated relay optics and a polarizing unit, and the
spectroscopic sub-channel, which shares the filters and the
detector with the UV-EUV imaging one, but includes a grating
instead of the secondary mirror.
The tolerance analysis of such an instrument is quite complex:
in fact not only the optical performance for the 3 sub-channels
has to be maintained simultaneously, but also the positions of M0
and of the occulters (IEO, internal occulter and Lyot stop), which
guarantee the optimal disk light suppression, have to be taken
into account as tolerancing parameters.
In the aim of assuring the scientific requirements are optimally
fulfilled for all the sub-channels, the preliminary results of
manufacturing, alignment and stability tolerance analysis for the
whole instrument will be described and discussed
Determinants of maxillary canine impaction : retrospective clinical and radiographic study
The aim of this study is to evaluate determinants of maxillary canine impaction taking into account both canine position related variables and the pattern of facial growth. A retrospective clinical and radiographic analysis was carried out on 109 patients aged between 9 and 10 years at the time of first evaluation. At baseline, SN-GoMe angle, the interincisal angle, the canine angle ? and the canine distance d were used to characterize canine location and vertical facial growth. At the end of a two years follow up period the eruption state of each canine of each patient was recorded and accordingly classified as erupted or impacted on a clinical and radiographic basis. Univariate and multivariate statistical analyses were performed, including correlation among the studied variables and principal components analysis; several machine learning methods were also used in order to built a predictive model. At the end of the two years follow up period after the first examination, 54 (24.77%) canines were classified as impacted. Except for Angle ? values, there were no statistically significant differences between impacted and erupted canines. The studied variables were not significantly correlated, except for the SN-GoMe Angle and the distance d in the impacted canine group and the angle ? and the distance d in erupted canines group. All variables, except for SN-GoMe Angle in erupted canines, have a partial communality with the first two principal components greater than 50%. Among the learning machine methods tested to classify data, the best performance was obtained by the random forest method, with an overall accuracy in predicting canine eruption of 88.3%. The studied determinants are easy to perform measurements on 2D routinely executed radiographic images; they seems independently related to canine impaction and have reliable accuracy in predicting maxillary canine eruption
Post-orthodontic position of lower incisors and gingival recession : a retrospective study
To evaluate if changes in lower incisor position following orthodontic treatment are correlated with development of gingival recessions. Pre- and post-treatment digital models and lateral cephalograms of 22 subjects were collected retrospectively. The clinical crown length, gingival scallop, and papilla height of the central lower incisor were measured along with the cephalometric incisor?s inclination, the distance from the mandibular plane, and the distance between the Infradentale and Menton points. Statistical correlations between gingival and cephalometric variables were studied. In addition, two groups were defined based on the post-treatment incisor inclination value (?normal? or ?proclined?) and compared. The incisor inclination was correlated with the change in gingival scallop and papilla height. Moreover, there was a statistically significant difference in clinical crown height and gingival scallop between the ?normal? group and the ?proclined? group. Changes in lower incisor position, especially an excessive proclination, after orthodontic treatment may play a role in the development of gingival recession
Transcriptional Hallmarks of Noonan Syndrome and Noonan-Like Syndrome with Loose Anagen Hair
Noonan syndrome (NS) is among the most common nonchromosomal disorders affecting development and growth. NS is genetically heterogeneous, being caused by germline mutations affecting various genes implicated in the RAS signaling network. This network transduces extracellular signals into intracellular biochemical and transcriptional responses controlling cell proliferation, differentiation, metabolism, and senescence. To explore the transcriptional consequences of NS-causing mutations, we performed global mRNA expression profiling on peripheral blood mononuclear cells obtained from 23 NS patients carrying heterozygous mutations in PTPN11 or SOS1. Gene expression profiling was also resolved in five subjects with Noonan-like syndrome with loose anagen hair (NS/LAH), a condition clinically related to NS and caused by an invariant mutation in SHOC2. Robust transcriptional signatures were found to specifically discriminate each of the three mutation groups from 21 age- and sex-matched controls. Despite the only partial overlap in terms of gene composition, the three signatures showed a notable concordance in terms of biological processes and regulatory circuits affected. These data establish expression profiling of peripheral blood mononuclear cells as a powerful tool to appreciate differential perturbations driven by germline mutations of transducers involved in RAS signaling and to dissect molecular mechanisms underlying NS and other RASopathies. Hum Mutat 33:703–709, 2012. © 2012 Wiley Periodicals, Inc
Effects of Tibetan Music on Neuroendocrine and Autonomic Functions in Patients Waiting for Surgery: A Randomized, Controlled Study
Background. The aim of this study was to investigate the effects of listening to Tibetan music on anxiety and endocrine, autonomic, cognitive responses in patients waiting for urologic surgery. Methods. Sixty patients waiting for surgery were enrolled to the study. They were randomized in music (M) and control (C) groups. The M group listened to a low-frequency Tibetan music for 30 min (T0–T30) through headphones, and the C group wore headphones with no sound. The State Trait Anxiety Inventory Questionnaire (STAI) Y-1 was administered at T0 and T30. Normalized low (LFnu) and high frequencies (HFnu) of heart rate variability, LF/HF ratio, and galvanic skin response (GRS) data were analyzed at T0, T10, T20, T30, and T35. The salivary α-amylase (sAA) samples were collected at T0, T35, and T45. Results. In the M group, the STAI Y-1 score decreased at T30 versus baseline p<0.001, sAA levels decreased at T35 versus T0p=0.004, and GSR remained unchanged. In the C group, the STAI Y-1 score remained unchanged, sAA level increased at T35 versus T0p<0.001, and GSR slightly increased at T35 versus baseline p=0.359. LFnu was lower, and HFnu was significantly higher (T10–T30) in M versus C group. Mean LF/HF ratio slightly reduced in the M group. Conclusions. Our results suggest that preoperative listening to relaxing Tibetan music might be a useful strategy to manage preoperative anxiety
Altered Gene Expression Encoding Cytochines, Grow Factors and Cell Cycle Regulators in the Endometrium of Women with Chronic Endometritis
To evaluate the expression of genes encoding cytokines, grow factors and cell cycle regulators in the proliferative endometrium of women with chronic endometritis (CE) compared to controls. We performed a case-control study on seven women with CE as diagnosed by hysteroscopy and histology (Cases) compared to six women without CE (Controls). All women underwent diagnostic hysteroscopy plus endometrial biopsy during the mid-proliferative phase of the menstrual cycle. Endometrial samples were divided into two different aliquots for histological and molecular analyses. The endometrial expression profile of 16 genes encoding proteins involved in the inflammatory process, proliferation and cell cycle regulation/apoptosis was assessed by using high-throughput qPCR. Study endpoints were between-group differences in the expression of VEGF A, VEGF B, VEGF C, EGF, TNF, TGF B1, IFNG, TP73, TP73L, BAXva, CDC2, CDC2va, CCND3, CCNB1, BAX and IL12. RESULTS: VEGF A, VEGF B, VEGF C, EGF, TNF, TGF B1, IFNG, TP73, TP73L, BAXva, CDC2, CDC2va, CCND3, CCNB1 were significantly overexpressed in women with CE compared to controls, while BAX and IL12 had similar expression between groups. In women with CE, we found an altered endometrial expression of genes involved in inflammatory, cell proliferation, and apoptosis processes. The dominance of proliferative and anti-apoptotic activity in CE may potentially promote the development of polyps and hyperplastic lesions
Design of virtual reality based HMIs (Human Machine Interfaces) of complex systems
onautical transport system is rapidly growing and more demanding. It has become a total system of complex systems in which the human is recognized as the decisional point that is asked to act quickly and safely. In this context, innovative technologies provide the challenge to design revolutionary Human Machine Interfaces for the people involved.In this paper a report of recent works in Human Machine Interfaces in aeronautics developed at the University of Bologna is presented. Synthetic visualization and task automation are the main commonalities in these projects. What we can expect from the future is then explored through an insight into technological aspects. © 2013 IEEE