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Il testo si propone di dare una preparazione introduttiva al corso di meccanica applicata alle macchine le cui problematiche fanno spesso ricorso ai concetti teorici riguardanti la cinematica e dinamica del corpo rigido. In esso tali argomenti vengono infatti trattati in una forma classica, con l'intento di privilegiare gli aspetti concettuali rispetto a quelli numerici, questi ultimi in genere preferiti nei testi di cinematica e dinamica dei sistemi multibody (corpi rigidi).

Several lines of experimental evidence suggest that sex hormones may influence the development and activity of chronic graft-versus-host disease (cGVHD), which frequently occurs in patients undergoing allogeneic bone marrow transplantation (ABMT). Following ABMT, young women are commonly treated with hormone replacement therapy (HRT) because of irreversible gonadal failure. It seemed therefore worthwhile to investigate the effects of this therapy on the activity of cGVHD. Premenopausal women treated with ABMT for hematological malignancies between January 1997 and December 2000 were evaluated for cGVHD activity. They were divided into two groups, depending on whether or not they were treated with HRT. Seventy-one women qualified for the present study: 39 received HRT (treated group), while 32 did not (controls). In both groups of patients, cGVHD activity score was comparable before the start of HRT. No differences were observed in cGVHD activity score between the HRT group and controls after 3, 6, 12, and 24 months from the start of HRT. Furthermore, HRT did not induce any increase in the cGVHD activity score in the treated group of patients at any time from the start of HRT. According to present data, HRT did not appear to influence the activity of cGVHD in young women who underwent ABMT for hematological malignancies. Therefore, we can safely propose this therapy for women with gonadal failure after ABMT.

To prescribe feasible and medically safe exercise interventions for obese adolescents, it remains to be determined whether exercise tolerance is altered and whether anomalous cardiopulmonary responses during maximal exercise testing are present. Studies that examined cardiopulmonary responses to maximal exercise testing in obese adolescents were searched: cardiopulmonary exercise tests with respiratory gas exchange measurements of peak oxygen uptake (VO2peak) were performed and comparisons between obese and lean adolescents were made. Study quality was assessed using a standardized item list. By meta-analyses VO2peak, peak cycling power output (Wpeak) and peak heart rate (HRpeak) were compared between groups. Nine articles were selected (333 obese vs. 145 lean adolescents). VO2peak (L min(-1)), HRpeak and Wpeak were not different between groups (P ≥ 0.10), while a trend was found for a reduced VO2peak (mL min(-1) kg(-1) lean tissue mass) (P=0.07) in obese vs. lean adolescents. It remained uncertain whether anomalous cardiopulmonary responses occur during maximal exercise testing in obese adolescents. In conclusion, a trend was found for lowered VO2peak (mL min(-1)kg(-1) lean tissue mass) in obese vs. lean adolescents. Whether cardiopulmonary anomalies during maximal exercise testing would occur in obese adolescents remains uncertain. Studies are therefore warranted to examine the cardiopulmonary response during maximal exercise testing in obese adolescents.

Sas TC, de Muinck Keizer-Schrama SM, Stijnen T, Jansen M, Otten BJ, Hoorweg-Nijman JJ, Vulsma T, Massa GG, Rouwe CW, Reeser HM, Gerver WJ, Gosen JJ, Rongen-Westerlaken C, Drop SL.Department of Pediatrics, Sophia Children's Hospital, Rotterdam, The Netherlands. sas@alkg.azr.nlShort stature and ovarian failure are the main features in Turner syndrome (TS). To optimize GH and estrogen treatment, we studied 68 previously untreated girls with TS, age 2-11 yr, who were randomly assigned to one of three GH dosage groups: group A, 4 IU/m2 day (approximately 0.045 mg/kg x day); group B, first yr 4, thereafter 6 IU/m2 x day (approximately 0.0675 mg/kg/day); group C, first yr 4, second yr 6, thereafter 8 IU/m2 x day (approximately 0.090 mg/kg x day). In the first 4 yr of GH treatment, no estrogens for pubertal induction were given to the girls. Thereafter, girls started with 17beta-estradiol (5 microg/kg bw x day, orally) when they had reached the age of 12 yr. Subjects were followed up until attainment of adult height or until cessation of treatment because of satisfaction with the height achieved. Seven-year data of all girls were evaluated to compare the growth-promoting effects of three GH dosages during childhood. After 7 yr, 85% of the girls had reached a height within the normal range for healthy Dutch girls. The 7-yr increment in height SD-score was significantly higher in groups B and C than in group A. In addition, we evaluated the data of 32 of the 68 girls who had completed the trial after a mean duration of treatment of 7.3 yr (range, 5.0 - 8.75). Mean (SD) height was 158.8 cm (7.1), 161.0 cm (6.8), and 162.3 cm (6.1) in groups A, B, and C, respectively. The mean (SD) difference between predicted adult height before treatment and achieved height was 12.5 cm (2.1), 14.5 cm (4.0), and 16.0 cm (4.1) for groups A, B, and C, respectively, being significantly different between group A and group C. GH treatment was well tolerated in all three GH dosage groups. In conclusion, GH treatment starting in relatively young girls with TS results in normalization of height during childhood, as well as of adult height, in most of the individuals. With this GH and estrogen treatment regimen, most girls with TS can grow and develop much more in conformity with their healthy peers.Publication Types: Clinical Trial Randomized Controlled Trial

In this paper, a model describing the castor three-dimensional dynamic behaviour, is presented. A procedure, based on the Udwadia-Kalaba formulation has been implemented to write the castor non-linear motion equations. The model takes into account the flexural and lateral compliance of the castor frame and the phenomena related to the wheel rotation. To prescind from the wheel-road interaction parameters, the hypothesis of no sideslip of the wheel has been adopted but other tire models can be easily implemented. The non-linear system stability is evaluated integrating the motion equation and performing fitting procedure on the natural steering oscillation.

Greenhouse modules and regenerative life-support systems are critical for long-duration space missions and future settlements on the Moon and Mars; understanding their mechanisms and issues on Earth in remote areas is a first step towards their space adaptation. To follow up with studies performed in NASA‘s Deep Space Habitat and deployed at NASA Desert Research and Technology Studies test site in 2010 and 2011, and at NASA Johnson Space Center in 2012, three sole-source LED lighting systems – commercial-off-the-shelf “UFO” red and blue LED grow lights, AIBC’s super-slim whiteEx70Dim panels, and Heliospectra multispectral LX60 lamp – were tested during the four-month HI-SEAS (Hawaii Space Exploration and Analog Simulation) analog mission. The primary objective of this study was to assess the effects of different wavelengths on lettuce and radish growth in a semi-controlled environment. Crew time required to take care of plants was also assessed. A Biomass Production System for Education (BPSe) unit developed by ORBITEC and modelled after their Deployable Vegetable Production System was placed inside the habitat and available for crew interaction and recreational purposes. Preliminary results regarding psychological benefits of plants in remote areas during long-term isolation are presented.

In this paper we present maps of K, eU, and eTh abundances of Elba Island (Italy) obtained with a multivariate spatial interpolation of airborne ��-ray data using the constraints of the geologic map. The radiometric measurements were performed by a module of four NaI(Tl) crystals of 16 L mounted on an autogyro. We applied the collocated cokriging (CCoK) as a multivariate estimation method for interpolating the primary under-sampled airborne ��-ray data considering the well-sampled geological information as ancillary variables. A random number has been assigned to each of 73 geological formations identified in the geological map at scale 1:10,000. The non-dependency of the estimated results from the random numbering process has been tested for three distinct models. The experimental cross-semivariograms constructed for radioelement-geology couples show well-defined co-variability structures for both direct and crossed variograms. The high statistical correlations among K, eU, and eTh measurements are confirmed also by the same maximum distance of spatial autocorrelation. Combining the smoothing effects of probabilistic interpolator and the abrupt discontinuities of the geological map, the results show a distinct correlation between the geological formation and radioactivity content. The contour of Mt. Capanne pluton can be distinguished by high K, eU and eTh abundances, while different degrees of radioactivity content identify the tectonic units. A clear anomaly of high K content in the Mt. Calamita promontory confirms the presence of felsic dykes and hydrothermal veins not reported in our geological map. Although we assign a unique number to each geological formation, the method shows that the internal variability of the radiometric data is not biased by the multivariate interpolation., 43 pages, 9 figures, 5 tables. In Remote Sensing of Environment (2013)