In the context of tele-monitoring, great interest is presently devoted to physical activity, mainly of elderly or people with disabilities. In this context, many researchers studied the recognition of activities of daily living by using accelerometers. The present work proposes a novel algorithm for activity recognition that considers the variability in movement speed, by using dynamic programming. This objective is realized by means of a matching and recognition technique that determines the distance between the signal input and a set of previously defined templates. Two different approaches are here presented, one based on Dynamic Time Warping (DTW) and the other based on the Derivative Dynamic Time Warping (DDTW). The algorithm was applied to the recognition of gait, climbing and descending stairs, using a biaxial accelerometer placed on the shin. The results on DDTW, obtained by using only one sensor channel on the shin showed an average recognition score of 95%, higher than the values obtained with DTW (around 85%). Both DTW and DDTW consistently show higher classification rate than classical Linear Time Warping (LTW).

Molecular hydrogen is the most abundant molecule in the Universe and dominates the mass budget of the gas, particularly in regions of star formation. H2 is also an important chemical intermediate in the formation of larger species and can be an important gas coolant when the medium lacks metals. Because of the inefficiency of gas-phase reactions to form H2, this molecule is generally thought to form on grain surfaces. Observations of H2 in a wide variety of objects showed that this molecule could form efficiently over a wide range of physical conditions. To understand the mechanism responsible for such an efficient formation, we developed a model for molecular hydrogen formation on grain surfaces. This model considers the interaction between atom and surface as beeing either weak (Van der Waals interactionphysisorption) or strong (covalent bound-chemisorption), as well as the mobility of the atom on a surface due to quantum mechanical diffusion and thermal hopping. This model solves the time-dependent kinetic rate equation for the formation of molecular hydrogen and its deuterated forms. Our results have been benchmarked with laboratory experiments on silicates, carbonaceous and graphitic surfaces. This comparison allowed us to derive some characteristics of the considered surfaces. An extension of our model to astrophysical conditions gives an estimate of H 2 formation efficiency for a wide range of physical conditions. One of our main results is the efficient formation of molecular hydrogen for gas and grain temperatures up to several hundreds of kelvins. We also compared our predictions to observations in astrophysical objects such as photodissociation regions (PDRs). The addition of deuterium in our model for the formation of HD and D 2 molecules is also discussed.

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To investigate whether persistent microalbuminuria is related to altered levels of both lipids and apolipoproteins in Type 2 diabetes mellitus serum total-cholesterol, triglycerides, HDL-cholesterol, LDL-cholesterol, apolipoprotein A-I, and apolipoprotein B were measured by standard methods in a group of Type 2 diabetic patients affected by persistent microalbuminuria (albumin excretion rate (AER) 20-200 micrograms min-1) as compared with a group of sex- and age-matched non-microalbuminuric patients (AER less than 20 micrograms min-1). The groups were stratified according to a short (less than or equal to 5 years) or a longer (greater than 5 years) duration of diagnosed diabetes. Microalbuminuria was not associated with significant changes of serum total-cholesterol, triglycerides, HDL-cholesterol, LDL-cholesterol, and apolipoproteins in the group of patients with a duration of disease greater than 5 years, while microalbuminuric patients less than or equal to 5 years from diagnosis (n = 11) had serum total-cholesterol, triglycerides, LDL-cholesterol, and apoprotein B higher than non-microalbuminuric control patients (n = 26) (cholesterol 6.2 +/- 0.9 vs 5.1 +/- 1.0 mmol l-1 (p = 0.003); triglycerides 2.1 +/- 0.7 vs 1.7 +/- 1.3 mmol l-1 (p = 0.03); LDL-cholesterol 4.1 +/- 0.8 vs 3.0 +/- 0.7 mmol l-1 (p less than 0.001); apo-B 1.3 +/- 0.3 vs 1.1 +/- 0.3 g l-1 (p = 0.02). In these patients with shorter duration of diabetes many of the serum lipid measures correlated positively with AER.

Metabolism of polyamines (spermidine and spermine) is known to be strictly related to the growth processes of eukaryotic cells. Since cell replication processes appear altered in insulin-dependent diabetes mellitus (IDDM), especially when associated with its microvascular complications, the aim of this study was measuring serum spermidine oxidase activity (SOA), a key enzyme in the metabolic pathway of polyamines, in 47 patients with IDDM as compared with 63 healthy control subjects matched for age and sex. Mean SOA levels +/- SD were significantly lower in IDDM patients (177.4 +/- 57.2 mu kat/l) than in controls (247.6 +/- 68.1 mu kat/l; p less than 0.001), being SOA inversely related with daily insulin dose. SOA was moreover significantly higher (but similar to controls) in the group with increased urinary albumin excretion rate (AER persistently greater than 20 micrograms/min); (n = 17; 213.1 +/- 62.6 mu kat/l) in comparison with normoalbuminuric subjects (n = 30; 156.6 +/- 43.5 mu kat/l; F = 21.78; p = 0.0001). SOA was correlated with AER (r = 0.45; p = 0.001), independently of age, duration of disease, serum creatinine, body weight, blood pressure and metabolic control, as shown by a multiple regression analysis model (p = 0.003). Presence of background retinopathy was not associated with modified levels of SOA, which was conversely higher, although not significantly, in the patients with proliferative retinal lesions. In conclusion serum SOA is deeply altered in IDDM patients, being markedly reduced in the whole group of patients and conversely independently increased up to the mean values of controls in presence of increased AER or advanced retinopathy.