23 research outputs found
The DREAMS experiment flown on the ExoMars 2016 mission for the study of Martian environment during the dust storm season
The DREAMS (Dust characterization, Risk assessment and Environment Analyser on the Martian Surface) instrument on Schiaparelli lander of ExoMars 2016 mission was an autonomous meteorological station designed to completely characterize the Martian atmosphere on surface, acquiring data not only on temperature, pressure, humidity, wind speed and its direction, but also on solar irradiance, dust opacity and atmospheric electrification; this comprehensive set of parameters would assist the quantification of risks and hazards for future manned exploration missions mainly related to the presence of airborne dust. Schiaparelli landing on Mars was in fact scheduled during the foreseen dust storm season (October 2016 in Meridiani Planum) allowing DREAMS to directly measure the characteristics of such extremely harsh environment. DREAMS instrument’s architecture was based on a modular design developing custom boards for analog and digital channel conditioning, power distribution, on board data handling and communication with the lander. The boards, connected through a common backbone, were hosted in a central electronic unit assembly and connected to the external sensors with dedicated harness. Designed with very limited mass and an optimized energy consumption, DREAMS was successfully tested to operate autonomously, relying on its own power supply, for at least two Martian days (sols) after landing on the planet. A total of three flight models were fully qualified before launch through an extensive test campaign comprising electrical and functional testing, EMC verification and mechanical and thermal vacuum cycling; furthermore following the requirements for planetary protection, contamination control activities and assay sampling were conducted before model delivery for final integration on spacecraft. During the six months cruise to Mars following the successful launch of ExoMars on 14th March 2016, periodic check outs were conducted to verify instrument health check and update mission timelines for operation. Elaboration of housekeeping data showed that the behaviour of the whole instrument was nominal during the whole cruise. Unfortunately DREAMS was not able to operate on the surface of Mars, due to the known guidance anomaly during the descent that caused Schiaparelli to crash at landing. The adverse sequence of events at 4 km altitude anyway triggered the transition of the lander in surface operative mode, commanding switch on the DREAMS instrument, which was therefore able to correctly power on and send back housekeeping data. This proved the nominal performance of all DREAMS hardware before touchdown demonstrating the highest TRL of the unit for future missions. The spare models of DREAMS are currently in use at university premises for the development of autonomous units to be used in cubesat mission and in probes for stratospheric balloons launches in collaboration with Italian Space Agency
Cognitive functioning, emotional processing, mood, and personality variables before and after stereotactic surgery: a study of 8 cases with chronic neuropathic pain
BACKGROUND: Stereotactic central lateral thalamotomy (CLT) has been applied as a treatment for chronic intractable neuropathic pain. However, it is not clear whether this intervention influences the emotional and cognitive impairments observed in patients who have chronic neuropathic pain.
OBJECTIVE: To investigate neuropsychological functions and emotional processing in patients with chronic neuropathic pain compared with healthy volunteers and to explore the neuropsychiatric effect of the CLT.
METHODS: We investigated pain ratings, cognitive functions, emotional processes, and personality variables before and after surgery in 8 patients with intractable neuropathic pain. Patients were tested before and 3 months after CLT by the use of neuropsychological tests; clinical scales for depression, anxiety, anhedonia, and anger regulation; a personality test; and 2 experimental tasks testing the theory of mind as well as the ability to recognize facial emotional expressions. Nine age- and sex-matched control subjects were tested once using the same procedure.
RESULTS: The comparison of the patient group before surgery with the control group evidenced significant differences on the cognitive assessments, the depression and anxiety scores, as well as on the somatic complaint subscale of the personality test. Three months after CLT, patients experienced a significant improvement in their depression scores. There were no additional postsurgical cognitive impairments.
CONCLUSION: For our patients with chronic neuropathic pain, CLT provided pain relief and reduction of their depression scores without causing postsurgical cognitive impairments
Bending test for capturing the vivid behavior of giant reeds, returned through a proper fractional visco-elastic model
This paper presents results of experimental investigations made to evaluate the vivid behavior of giant reed Arundo donax. In particular, attention was paid to the relationship between visco-elastic properties and moisture content, which is widely recognized as one of the key factor that influences the mechanical properties of all wood-based materials. To this aim, after a controlled drying treatment on samples of reed, stress relaxation tests in three point bending configuration were performed to evaluate the effects of moisture content on visco-elastic behavior of the giant reed. Further, the novel aspect of this paper is that of using an Euler-Bernoulli model embedded with an advanced visco-elastic constitutive law to fit experimental data of bending tests. Such a model of continuum beam takes into account different constitutive laws of viscoelasticity, being natural materials visco-elastic
Su di un caso clinico di stipsi cronica dell’adulto dopo trattamento chirurgico per MAR in età neonatale
Nondermatomal somatosensory deficits in chronic pain are associated with cerebral grey matter changes
OBJECTIVES: Widespread sensory deficits occur in 20-40% of chronic pain patients on the side of pain, independent of pain aetiology, and are known as nondermatomal sensory deficits (NDSDs). NDSDs can occur in absence of central or peripheral nervous system lesions. We hypothesised that NDSDs were associated with cerebral grey matter changes in the sensory system and in pain processing regions, detectable with voxel-based morphometry.
METHODS: Twenty-five patients with NDSDs, 23 patients without NDSDs ("pain-only"), and 29 healthy controls were studied with high resolution structural MRI of the brain. A comprehensive clinical and psychiatric evaluation based on Diagnostic and Statistical Manual was performed in all patients.
RESULTS: Patients with NDSDs and "pain-only" did not differ concerning demographic data and psychiatric diagnoses, although anxiety scores (HADS-A) were higher in patients with NDSDs. In patients with NDSDs, grey matter increases were found in the right primary sensory cortex, thalamus, and bilaterally in lateral temporal regions and the hippocampus/fusiform gyrus. "Pain-only" patients showed a bilateral grey matter increase in the posterior insula and less pronounced changes in sensorimotor cortex.
CONCLUSIONS: Dysfunctional sensory processing in patients with NDSDs is associated with complex changes in grey matter volume, involving the somatosensory system and temporal regions
Nondermatomal somatosensory deficits in chronic pain are associated with cerebral grey matter changes
OBJECTIVES
Widespread sensory deficits occur in 20-40% of chronic pain patients on the side of pain, independent of pain aetiology, and are known as nondermatomal sensory deficits (NDSDs). NDSDs can occur in absence of central or peripheral nervous system lesions. We hypothesised that NDSDs were associated with cerebral grey matter changes in the sensory system and in pain processing regions, detectable with voxel-based morphometry.
METHODS
Twenty-five patients with NDSDs, 23 patients without NDSDs ("pain-only"), and 29 healthy controls were studied with high resolution structural MRI of the brain. A comprehensive clinical and psychiatric evaluation based on Diagnostic and Statistical Manual was performed in all patients.
RESULTS
Patients with NDSDs and "pain-only" did not differ concerning demographic data and psychiatric diagnoses, although anxiety scores (HADS-A) were higher in patients with NDSDs. In patients with NDSDs, grey matter increases were found in the right primary sensory cortex, thalamus, and bilaterally in lateral temporal regions and the hippocampus/fusiform gyrus. "Pain-only" patients showed a bilateral grey matter increase in the posterior insula and less pronounced changes in sensorimotor cortex.
CONCLUSIONS
Dysfunctional sensory processing in patients with NDSDs is associated with complex changes in grey matter volume, involving the somatosensory system and temporal regions