21 research outputs found
The First-Ever Asteroid Fly-By Performed by a CubeSat: Outcomes of the LICIACube Mission
Transported onboard NASA Double Asteroid Redirection Test (in short, DART) spacecraft developed by Johns Hopkins Applied Physics Laboratory (APL), the Italian Space Agency (ASI) Light Italian CubeSat for Imaging of Asteroids (in short, LICIACube) played a crucial role in the homonymous mission that took place in September 2022. Its main purpose has been to document the effects of the intentional impact of DART probe with Dimorphos, the minor-planet moon of the 65803 Didymos asteroid system. Along this first-ever planetary defense mission against Near-Earth Objects (NEOs), LICIACube successfully completed the first-ever asteroid fly-by performed by a CubeSat.
With a maximum Earth distance of approximately 14 million km during its operative phase, LICIACube is currently one of the nanosatellites that operated the farthest from our planet in a robotic exploration mission. Once separated from DART, the micro-satellite followed its mothercraft along its approach trajectory: its optical system, composed by two digital cameras, is the core of the Autonomous Attitude Control System which allowed to gather images of the two asteroids during a very fast fly-by. This paper discusses how LICIACube behaved in flight, with a focus on the embedded real-time hardware-accelerated imaging capabilities and the Autonomous Attitude Control System as a whole. These technologies allowed the CubeSat to simultaneously operate its two optical payloads both for tracking and science purposes. During the approximately 5-minute-long fly-by, tracking has been performed using the primary telescopic grayscale camera (LICIACube Explorer Imaging for Asteroid, LEIA) to provide rapid feedback to the satellite Autonomous Attitude Control System controlling its attitude, thus maintaining the pointing towards the target. The telescope was exploited to track the main body (Didymos) during the initial phases of the fly-by, switching then to Dimorphos in the vicinity of the closest approach, which occurred with a distance of about 50km and a relative speed of approximately 7 km/s. On the other hand, the secondary payload allowed to capture and store wide-angle images of DART impact with the asteroid, by means of the secondary RGB camera (LICIACube Unit Key Explorer, LUKE) and with a maximum image acquisition rate of 3 pictures per second.
In the first section of this paper, the LICIACube CubeSat System is introduced in the DART mission context. In second place, Argotec\u27s all-in-house HAWK-6 platform upon which LICIACube was built is discussed in detail. Followingly, LICIACube in-flight performances are examined with a focus on the Autonomous Attitude Control System. Mission results are included, with real-time telemetry data collected during operations and images of DART captured before and after the impact with Dimorphos
LICIACube on DART Mission: An Asteroid Impact Captured by Italian Small Satellite Technology
In the frame of the Planetary Defense program, NASA developed the Double Asteroid Redirection Test (DART) mission and the Italian Space Agency joined the effort. DART’s spacecraft will act as a kinetic impactor by deliberately crashing into the moonlet of Didymos binary system (i.e. Didymos-B) while the effects of the impact will be observed by a small satellite, the Light Italian CubeSat for Imaging of Asteroid (LICIACube) and ground-based telescopes. LICIACube, an Italian Space Agency (ASI) mission, will fly with a relative velocity of approximately 6.5 km/s and it will document the effects of the impact, the crater and the evolution of the plume generated by the collision. LICIACube will have to maintain the asteroid\u27s pointing at an angular speed of approximately 10 deg/s to fly-by the asteroid close to the Didymos-B surface. The images acquired by LICIACube will be processed onboard through the autonomous navigation algorithm to identify the asteroid system and control the satellite attitude. They will also help the scientific community and provide feedback to the Planetary Defense program, pioneered by the Space Agencies. This deep-space mission is based on a small scale but highly technological platform, whose development is involving both the Italian technical and scientific community
is osteoporosis risk in anorexia nervosa underestimated a case report series
Introduction: Anorexia nervosa (AN) is a mental disorder whose features are deliberate weight loss, disordered body image, and intrusive overvalued fears of gaining weight. Long-term consequences of AN include endocrine dysfunctions leading to secondary amenorrhea, bone loss and/or osteoporosis with an increased risk of bone fracture. Therefore young women with AN may develop a risk for bone fractures comparable to that of postmenopausal women. Methods: In this case report series Bone Mineral Density (BMD) was examined by Dual energy X-ray Absorptiometry (DXA) in 19 hospitalized patients with diagnosis of AN and prolonged amenorrhea. Results: All patients showed a lumbar/femoral bone loss or osteoporosis, with an increased fracture risk comparable to that of postmenopausal women. Conclusions: Our observation suggests that DXA evaluation of anorexic patients with prolonged amenorrhea would be helpful to prevent fracture risk in this population of patients. However, although DXA is almost routinely recommended in women over 65, it is not in young AN patients with prolonged amenorrhea
The SSDC Role in the LICIACube Mission: Data Management and the MATISSE Tool
Light Italian Cubesat for Imaging of Asteroids (LICIACube) is an Italian mission managed by the Italian Space
Agency (ASI) and part of the NASA Double Asteroid Redirection Test (DART) planetary defense mission. Its
main goals are to document the effects of the DART impact on Dimorphos, the secondary member of the (65803)
Didymos binary asteroid system, characterizing the shape of the target body and performing dedicated scientific
investigations on it. Within this framework, the mission Science Operations Center will be managed by the Space
Science Data Center (ASI-SSDC), which will have the responsibility of processing, archiving, and disseminating
the data acquired by the two LICIACube onboard cameras. In order to better accomplish this task, SSDC also plans
to use and modify its scientific webtool Multi-purpose Advanced Tool for Instruments for the solar system
Exploration (MATISSE), making it the primary tool for the LICIACube data analysis, thanks to its advanced
capabilities for searching and visualizing data, particularly useful for the irregular shapes common to several small
bodies
Disturbi dell'alimentazione e aspetti sessuali: implicazioni per la ricerca
INTRODUZIONE: In questa tesi viene descritta l'impostazione di una ricerca che ha come scopo la valutazione dell'associazione tra sintomatologia bulimica e pregressi abusi sessuali in pazienti portatrici di varianti alleliche a bassa funzionalitĂ del gene che codifica per il trasportatore della serotonina.
L'iter sperimentale seguito ha previsto una prima valutazione generica dalla quale sono emersi i presupposti per impostare la seconda fase della ricerca. Vengono quindi riferiti sia i risultati della ricerca preliminare che il substrato teorico che ha consentito di costruire il progetto sperimentale successivo.
DATI PRELIMINARI: In questo centro è stato eseguito uno studio con l'obiettivo di valutare le abitudini sessuali e le possibili disfunzioni sessuali, con il relativo tasso di prevalenza, presenti in una popolazione di pazienti affetti affetti da disturbo della condotta alimentare. Il campione delle paziente prese in esame era composto da 32 soggetti, con età medio di 25,50 anni. Sono state preliminarmente suddivise in sottogruppi sulla base del disturbo alimentare: il 34,4% della popolazione totale era affetto da Bulimia Nervosa senza condotte di eliminazione, il 15, 6% da Bulimia con condotte eliminatorie, il 21,9% da Anoressia Binging/Purging, il 15,6% da Anoressia Nervosa e il 12,5% da Binge Eating Disorder (BED).
La popolazione totale da noi esaminata presentava, per quanto riguarda le caratteristiche sessuologiche, un elevato tasso di prevalenza di Disfunzioni Sessuali (78.1%), con un Disturbo del Desiderio presente nel 56,3%, un Disturbo dell’Eccitazione nel 62,5%, un Disturbo dell’Orgasmo nel 34,4%, un Disturbo da Dolore nel 18,7% e un Episodio di Abuso Sessuale pregresso nel 12,5% dei casi.
I risultati che ci sono sembrati piĂą significativi sono stati: la netta maggioranza di pazienti affette da Bulimia Nervosa (BN) e un dato inatteso, vale a dire il 12,5% di pazienti che hanno riferito di aver subito abusi sessuali nel corso della loro vita.
Cercando in bibliografia dati riguardanti l'associazione tra BN e Abuso Sessuale, ci siamo imbattuti in alcuni studi che valutano la possibilitĂ che abusi sessuali possano predisporre l'insorgenza di Disturbi della Condotta Alimentare.
L'associazione tra abuso sessuale durante l'infanzia e sviluppo di disturbi della condotta alimentare era stato giĂ esplorato da Wonderlich nel 97. i
Il piĂą recente studio di Steiger del 2007 ha mostrato una associazione tra Sintomatologia Bulimica, Abuso sessuale e Polimorfismo 5HTTLPRii
SCOPO DELLA TESI: A nostro avviso questi studi aprono la strada per l'analisi di questa importante associazione, ma non considerano delle variabili che riteniamo essere di notevole importanza.
PREMESSE TEORICHE: Waller nel 92 ha dimostrato che pazienti bulimiche che hanno subito abuso sessuale presentano con maggior frequenza le abbuffate, seguite poi da condotte di eliminazione, se il molestatore era un parente, se l'abuso si verificava durante l'infanzia e se era associato a violenza fisica. iii iv
Analogamente nello studio di Baldo e Baldo nel 1996 è possibile notare che pazienti con storia di abuso intrafamiliare mostravano una sintomatologia alimentare più severa, rispetto a pazienti affette da DCA e con storia di abuso extrafamiliare.v
Hastings e Kern nel 1994 hanno anche evidenziato un collegamento tra severitĂ della sintomatologia bulimica e gravitĂ dell'abuso sessuale. Vittime di abuso che riportavano maltrattamenti perpetrati per lungo tempo, associati a contatto fisico, perpetrati da un genitore (sia biologico che adottivo) presentano un maggior rischio di sviluppare una sintomatologia bulimica particolarmente grave.vi
PROPOSTA DI STUDIO: Sulla base di questi dati ci prefiggiamo di verificare con uno studio esteso, la correlazione tra Abuso Sessuale, predisposizione genetica e sintomatologia bulimica.
In particolar modo riteniamo opportuno che ognuno di questi aspetti debba essere estesamente analizzato.
Le caratteristiche dell'abuso sessuale devono essere definite con precisione, dando particolare risalto a: Tipo di Relazione esistente tra abusatore e vittima, Numero di Episodi, Età a cui si è verificato l'abuso, Se si è verificato l'uso della forza, Se è stato associato a violenza fisica. vii Queste informazioni posso essere raccolte durante un colloquio strutturato, durante il quale vengono eseguite domande mirate, oppure preferibilmente con un questionario opportunamente compilato, come ad esempio il Childhood Sexual Abuse (CSA). viii
Una valida alternativa potrebbe essere il questionario stilato dal Dott. Pellai per l'analisi e la prevenzione dell'abuso sessuale nell'infanzia e adolescenza. ix
La sintomatologia bulimica può essere valutata con questionari strutturati come: Eating Disorder Questionnaire (EDQ), Bulimic Investigatory Test Edinburgh (BITE), Eating Attitude Test (EAT), Eating Disorder Inventory (EDI.
Il Gene che codifica per il Trasportatore della Serotonina presenta due varianti alleliche. Una Variante Long (L) e una Short (S), che rispettivamente determinano una produzione normale o ridotta del Trasportatore per la Serotonina.x xi Recenti ricerche suggeriscono l'esistenza di una variante, poco frequente, del gene L: l'allele LG (originato per il polimorfismo di un singolo nucleotide, dovuto aalla sostituzione di base A → G) la cui funzionalità pare essere paragonabile a quella dell'allele S. xii xiii In base a queste informazioni sarebbe più corretto considerare il gene 5HTTLPR come triallelico, con 2 alleli a bassa funzionalità (S e LG) e un allele ad alta funzionalità (LA)
The Assessment of Emotional Dysregulation: Validation of Reactivity Intensity Polarity and Stability scale (RIPOST)
BACKGROUND: Emotional Dysregulation (ED) is a condition characterized by intense and rapid mood changes of both polarities and by the tendency to over-react to external stimuli, especially within the interpersonal field. ED is subordinate to the broader construct of affective disturbance, defined as a disruption in the multi-system response (subjective experience, expressive behaviours, physiology) of emotions, moods, and stress responses that can lead to impulsive behaviours. There are many important correlations between affective temperaments and different aspects of ED and impulsivity. Cyclothymic and irritable temperament proved to be positively linked with the trait impulsiveness. Attentional impulsiveness revealed significant positive correlations with depressive, cyclothymic, irritable and anxious temperament and negative correlation with hyperthymic temperament. ED, emotional impulsiveness, mood instability and emotional lability have been used to refer to similar conceptualizations and represents the temperamental basis of cyclothymia. Different degrees of ED, associated with changes of energy and motivation, are described in cluster B personality disorders and in all neurodevelopmental disorders. The fact that all these conditions share with cyclothymia difficulties in modulating their behaviours during emotional states suggests a plausible common neurophysiological basis. The association between ADHD and affective lability as well as stress intolerance, mood instability, and emotional over-reactivity has been analysed in several studies. Furthermore, it has been proposed that ED traits should be considered a core feature of ADHD, along with hyperactivity and inattention, rather than associated symptoms.
AIM OF THE STUDY: The main purpose of this study was to evaluate and validate the psychometric properties of the Italian version of the “Reactivity Intensity Polarity and Stability scale” (RIPoSt) in clinical populations of Cyclothymic and ADHD patients and control subjects. Our working hypotheses was the existence of higher RIPoSt scores in patients with a diagnosis of cyclothymia or ADHD than controls, and a correlation between the elevated emotional dysregulation and the cyclothymic temperament.
METHODS: The study sample consisted of 374 subjects (33.08 years, SD ± 11.5) divided in 51 ADHD patients, 120 cyclothymic patients and 203 adult healthy controls. There were 250 females (66.8%) and 124 males (33.2%). Reliability and validity were assessed by standard psychometric tests (Convergent Validity, Known Groups validity, Factor analysis). We examined the internal consistency of the RIPoSt scale, as well as the validity of this questionnaire, by testing its associations with an existing and validated scale for temperament evaluation (Brief TEMPS-M).
RESULTS: The reliability was excellent for both RIPOST total score and every single subscale, exceeding the value of .70 (ranging from .723 to .963). Only the Emotional Polarity (P/N) subscale showed a lower but still acceptable level of reliability with a .723 for the whole sample (and with values of the subscales ranging from .694 to .715). Every single subscale and the RIPOST total score were positively and significantly correlated with one another (p<.001), with Pearson’s coefficients ranging from .646 to .797. In addition, the subscale scores were highly correlated with the RIPOST total score, with coefficients ranging from .846 to .914. Moreover, RIPoSt total score was positively and strongly correlated with the Depressive and Cyclothymic Brief TEMPS-M subscales (Pearson’s coefficients respectively .700 and .800). Post hoc comparisons using the Scheffe’s test revealed a significant difference between the 3 groups, with higher scores for Cyclothymic and ADHD patients. Principal Components Analysis with Varimax rotation resulted in a 4-factor solution: the first with highest explained variance (16.570%) represents Emotional Intensity; the second identifies Emotional Instability (14.639% of variance); the third Emotional Impulsivity (11.438% of variance); the fourth Positive Emotionality (9.887% of variance). Post hoc comparisons using the Scheffe's test revealed significant differences in factor scores between the 3 groups, with higher scores for Cyclothymic and ADHD patients in factor 1, 2 and 3. No significant differences among groups were observed in the factor 4.
CONCLUSIONS: Excellent internal consistency was found as well as a strong convergent validity with the Brief TEMPS-M scale, who explored the temperament of the subjects. As expected, the questionnaire performed differently among the three diagnostic groups explored. The results also provided strong support for convergent validity, with a significant correlation with the Brief TEMPS-M scale. Particularly, all the RIPoSt scores appeared to be from moderately to strongly correlated with the with Cyclothymic, Irritable, Depressive and Anxious temperaments. There was no correlation with Hyperthymic temperament. The RIPoSt scale showed good psychometric properties, as outlined above, and might be a promising instrument to use in different psychiatric samples, in order to identify specific phenotypes to be used in clinical, neurobiological and genetic studies
Is osteoporosis risk in anorexia nervosa underestimated? A case report series
Introduction: Anorexia nervosa (AN) is a mental disorder whose features are deliberate weight loss, disordered body image, and intrusive overvalued fears of gaining weight. Long-term consequences of AN include endocrine dysfunctions leading to secondary amenorrhea, bone loss and/or osteoporosis with an increased risk of bone fracture. Therefore young women with AN may develop a risk for bone fractures comparable to that of postmenopausal women. Methods: In this case report series Bone Mineral Density (BMD) was examined by Dual energy X-ray Absorptiometry (DXA) in 19 hospitalized patients with diagnosis of AN and prolonged amenorrhea. Results: All patients showed a lumbar/femoral bone loss or osteoporosis, with an increased fracture risk comparable to that of postmenopausal women. Conclusions: Our observation suggests that DXA evaluation of anorexic patients with prolonged amenorrhea would be helpful to prevent fracture risk in this population of patients. However, although DXA is almost routinely recommended in women over 65, it is not in young AN patients with prolonged amenorrhea