Trinocular System for 3D motion and Dense Stucture Estimation

The relief of the seafloor is an important source of data for many scientists. In this paper we present an optical system to deal with underwater 3D reconstruction. This system is formed by three cameras that take images synchronously in a constant frame rate scheme. We use the images taken by these cameras to compute dense 3D reconstructions. We use Bundle Adjustment to estimate the motion ofthe trinocular rig. Given the path followed by the system, we get a dense map of the observed scene by registering the different dense local reconstructions in a unique and bigger one

Microvascular burden and Alzheimer-type lesions across the age spectrum.

The occurrence of microvascular and small macrovascular lesions and Alzheimer's disease (AD)-related pathology in the aging human brain is a well-described phenomenon. Although there is a wide consensus about the relationship between macroscopic vascular lesions and incident dementia, the cognitive consequences of the progressive accumulation of these small vascular lesions in the human brain are still a matter of debate. Among the vast group of small vessel-related forms of ischemic brain injuries, the present review discusses the cognitive impact of cortical microinfarcts, subcortical gray matter and deep white matter lacunes, periventricular and diffuse white matter demyelinations, and focal or diffuse gliosis in old age. A special focus will be on the sub-types of microvascular lesions not detected by currently available neuroimaging studies in routine clinical settings. After providing a critical overview of in vivo data on white matter demyelinations and lacunes, we summarize the clinicopathological studies performed by our center in large cohorts of individuals with microvascular lesions and concomitant AD-related pathology across two age ranges (the younger old, 65-85 years old, versus the oldest old, nonagenarians and centenarians). In conjunction with other autopsy datasets, these observations fully support the idea that cortical microinfarcts are the only consistent determinant of cognitive decline across the entire spectrum from pure vascular cases to cases with combined vascular and AD lesion burden.

Detection of moving groups among early type stars

Our procedure to detect moving groups in the solar neighbourhood (Chen et al., 1997) in the four-dimensional space of the stellar velocity components and age has been improved. The method, which takes advantadge of non-parametric estimators of density distribution to avoid any a priori knowledge of the kinematic properties of these stellar groups, now includes the effect of observational errors on the process to select moving group stars, uses a better estimation of the density distribution of the total sample and field stars, and classifies moving group stars using all the available information. It is applied here to an accurately selected sample of early-type stars with known radial velocities and Strömgren photometry. Astrometric data are taken from the HIPPARCOS catalogue (ESA, 1997), which results in an important decrease in the observational errors with respect to ground-based data, and ensures the uniformity of the observed data. Both the improvement of our method and the use of precise astrometric data have allowed us not only to confirm the existence of classical moving groups, but also to detect finer structures that in several cases can be related to kinematic properties of nearby open clusters or associations.

Somatosensory motor bodily representation cortical thinning in Tourette : effects of tic severity, age and gender

Introduction: Tourette syndrome (TS) implicates the disinhibition of the cortico-striatal-thalamic-cortical circuitry (CSTC). Previous studies used a volumetric approach to investigate this circuitry with inconsistent findings. Cortical thickness may represent a more reliable measure than volume due to the low variability in the cytoarchitectural structure of the grey matter. Methods: 66 magnetic resonance imaging scans were acquired from 34 TS (age range 10-25, mean 17.19±4.1) and 32 normal controls (NC) (age range 10-20, mean 16.33±3.56). Brain morphology was assessed using the fully automated Civet pipeline at the Montreal Neurological Institute. Results: We report (1) significant cortical thinning in the fronto-parietal and somatosensory-motor cortices in TS relative to NC (p<0.05); (2) TS boys showed thinner cortex relative to TS girls in the fronto-parietal cortical regions (p<0.05); (3) significant decrease in the fronto-parietal mean cortical thickness in TS with age relative to NC and in the pre-central cortex in TS boys relative to TS girls; (4) significant negative correlations between tic severity and the somatosensory-motor cortical thickness. Conclusions: TS revealed important thinning in brain regions particularly involved in the somatosensory/motor bodily representations which may play an important role in tics. Our findings are in agreement with Leckman et al. (1991) hypothesis stating that facial tics would be associated with dysfunction in an orofacial subset of the motor circuit, eye blinking with the occulo-motor circuit, whereas lack of inhibition to a dysfunction in the prefrontal cortex. Gender and age differences may reflect differential etiological factors, which have significant clinical relevance in TS and should be considered in developing and using diagnostic and therapeutic interventions.

Heel and toe clearance estimation for gait analysis using wireless inertial sensors.

Tripping is considered a major cause of fall in older people. Therefore, foot clearance (i.e., height of the foot above ground during swing phase) could be a key factor to better understand the complex relationship between gait and falls. This paper presents a new method to estimate clearance using a foot-worn and wireless inertial sensor system. The method relies on the computation of foot orientation and trajectory from sensors signal data fusion, combined with the temporal detection of toe-off and heel-strike events. Based on a kinematic model that automatically estimates sensor position relative to the foot, heel and toe trajectories are estimated. 2-D and 3-D models are presented with different solving approaches, and validated against an optical motion capture system on 12 healthy adults performing short walking trials at self-selected, slow, and fast speed. Parameters corresponding to local minimum and maximum of heel and toe clearance were extracted and showed accuracy ± precision of 4.1 ± 2.3 cm for maximal heel clearance and 1.3 ± 0.9 cm for minimal toe clearance compared to the reference. The system is lightweight, wireless, easy to wear and to use, and provide a new and useful tool for routine clinical assessment of gait outside a dedicated laboratory.

Melanin-based coloration covaries with ovary size in an age-specific manner in the barn owl.

While the adaptive function of black eumelanin-based coloration is relatively well known, the function of reddish-brown pheomelanin-based coloration is still unclear. Only a few studies have shown or suggested that the degree of reddish-brownness is associated with predator-prey relationships, reproductive parameters, growth rate and immunity. To gain insight into the physiological correlates of melanin-based coloration, I collected barn owl (Tyto alba) cadavers and examined the covariation between this colour trait and ovary size, an organ that increases in size before reproduction. A relationship is expected because melanin-based coloration often co-varies with sexual activity. The results showed that reddish-brown juveniles had larger ovaries than whiter juveniles particularly in individuals in poor condition and outside the breeding season, while in birds older than 2 years lightly coloured females had larger ovaries than reddish-brown conspecifics. As barn owls become less reddish-brown between the first and second year of age, the present study suggests that reddish-brown pheomelanic and whitish colorations are associated with juvenile- and adult-specific adaptations, respectively.

Influence of segmental chromosome abnormalities on survival in children over the age of 12 months with unresectable localised peripheral neuroblastic tumours without MYCN amplification.

BACKGROUND: The prognostic impact of segmental chromosome alterations (SCAs) in children older than 1 year, diagnosed with localised unresectable neuroblastoma (NB) without MYCN amplification enrolled in the European Unresectable Neuroblastoma (EUNB) protocol is still to be clarified, while, for other group of patients, the presence of SCAs is associated with poor prognosis. METHODS: To understand the role of SCAs we performed multilocus/pangenomic analysis of 98 tumour samples from patients enrolled in the EUNB protocol. RESULTS: Age at diagnosis was categorised into two groups using 18 months as the age cutoff. Significant difference in the presence of SCAs was seen in tumours of patients between 12 and 18 months and over 18 months of age at diagnosis, respectively (P=0.04). A significant correlation (P=0.03) was observed between number of SCAs per tumour and age. Event-free (EFS) and overall survival (OS) were calculated in both age groups, according to both the presence and number of SCAs. In older patients, a poorer survival was associated with the presence of SCAs (EFS=46% vs 75%, P=0.023; OS=66.8% vs 100%, P=0.003). Moreover, OS of older patients inversely correlated with number of SCAs (P=0.002). Finally, SCAs provided additional prognostic information beyond histoprognosis, as their presence was associated with poorer OS in patients over 18 months with unfavourable International Neuroblastoma Pathology Classification (INPC) histopathology (P=0.018). CONCLUSIONS: The presence of SCAs is a negative prognostic marker that impairs outcome of patients over the age of 18 months with localised unresectable NB without MYCN amplification, especially when more than one SCA is present. Moreover, in older patients with unfavourable INPC tumour histoprognosis, the presence of SCAs significantly affects OS.

Front-crawl instantaneous velocity estimation using a wearable inertial measurement unit.

Monitoring the performance is a crucial task for elite sports during both training and competition. Velocity is the key parameter of performance in swimming, but swimming performance evaluation remains immature due to the complexities of measurements in water. The purpose of this study is to use a single inertial measurement unit (IMU) to estimate front crawl velocity. Thirty swimmers, equipped with an IMU on the sacrum, each performed four different velocity trials of 25 m in ascending order. A tethered speedometer was used as the velocity measurement reference. Deployment of biomechanical constraints of front crawl locomotion and change detection framework on acceleration signal paved the way for a drift-free integration of forward acceleration using IMU to estimate the swimmers velocity. A difference of 0.6 ± 5.4 cm · s(-1) on mean cycle velocity and an RMS difference of 11.3 cm · s(-1) in instantaneous velocity estimation were observed between IMU and the reference. The most important contribution of the study is a new practical tool for objective evaluation of swimming performance. A single body-worn IMU provides timely feedback for coaches and sport scientists without any complicated setup or restraining the swimmer's natural technique.

Gaussian process framework for pervasive estimation of swimming velocity with body-worn IMU

Presented is an accurate swimming velocity estimation method using an inertial measurement unit (IMU) by employing a simple biomechanical constraint of motion along with Gaussian process regression to deal with sensor inherent errors. Experimental validation shows a velocity RMS error of 9.0 cm/s and high linear correlation when compared with a commercial tethered reference system. The results confirm the practicality of the presented method to estimate swimming velocity using a single low-cost, body-worn IMU.

Age and adverse drug reactions from psychopharmacological treatment: Data from the AMSP drug surveillance programme in Switzerland.

QUESTION UNDER STUDY: The frequency of severe adverse drug reactions (ADRs) from psychotropic drugs was investigated in hospitalised psychiatric patients in relation to their age. Specifically, the incidence of ADRs in patients up to 60 years was compared to that of patients older than 60 years. METHODS: Prescription rates of psychotropic drugs and reports of severe ADRs were collected in psychiatric hospitals in Switzerland between 2001 and 2010. The data stem from the drug surveillance programme AMSP. RESULTS: A total of 699 patients exhibited severe ADRs: 517 out of 28,282 patients up to 60 years (1.8%); 182 out of 11,446 elderly patients (1.6%, ns). Logistic regression analyses showed a significantly negative relationship between the incidence of ADRs and patients' age in general and in particular for weight gain, extrapyramidal motor system (EPMS) symptoms, increased liver enzymes and galactorrhoea. A significantly negative relationship was observed for age and the dosages of olanzapine, quetiapine, risperidone, valproic acid and lamotrigine. When comparing age groups, frequency of ADRs was lower in general for antipsychotic drugs and anticonvulsants, in particular for valproic acid in the elderly. Weight gain was found to be lower in the elderly for antipsychotic drugs, in particular for olanzapine. For the group of mood-stabilising anticonvulsants (carbamazepine, lamotrigine and valproic acid) the elderly exhibited a lower incidence of reported allergic skin reactions. CONCLUSION: The results suggest that for psychiatric inpatients the incidence of common severe ADRs (e.g., weight gain or EPMS symptoms) arising from psychotropic medication decreases with the age of patients.

Synorogenic extension: Quantitative constraints on the age and displacement of the Zanskar shear zone (northwest Himalaya)

subsequent extension-induced exhumation. Geochronological dating of various Structural, thermobarometric, and geochronological data place limits on the age and tectonic displacement along the Zanskar shear zone, a major north-dipping synorogenic extensional structure separating the high-grade metamorphic sequence of the High Himalayan Crystalline Sequence from the overlying low-grade sedimentary rocks of the Tethyan Himalaya, A complete Barrovian metamorphic succession, from kyanite to biotite zone mineral assemblages, occurs within the I-km-thick Zanskar shear zone. Thermobarometric data indicate a difference In equilibration depths of 12 +/- 3 km between the lower kyanite zone and the garnet zone, which is Interpreted as a minimum estimate for the finite vertical displacement accommodated by the Zanskar shear zone. For the present-day dip of the structure (20 degrees), a simple geometrical model shows that a net slip of 35 +/- 9 km is required to regroup these samples to the same structural level. Because the kyanite to garnet zone rocks represent only part of the Zanskar shear zone, and because its original dip may have been less than the present-day dip, these estimates fur the finite displacement represent minimum values. Field relations and petrographic data suggest that migmatization and associated leucogranite intrusion in the footwall of the Zanskar shear zone occurred as a continuous profess starting at the Barrovian metamorphic peak and lasting throughout the subsequent extension-induced exhumation. Geochronological dataing of various leucogranitic plutons and dikes in the Zanskar shear zone footwall indicates that the main ductile shearing along the structure ended by 19.8 Ma and that extension most likely initiated shortly before 22.2 Ma.

Age and growth of leaping grey mullet (Liza saliens (Risso, 1810)) in Minorca (Balearic Islands)

A population of leaping grey mullet (Liza saliens (Risso, 1810) was studied in order to measure seasonal and annual growth rates. The annual growth rates were similar to those reported for other populations from the central Western Mediterranean and intermediate between those living in northern and southern areas. As usual, the growth rate of adult males was slower than that of females. Males reached adulthood in their third summer. Females of the same age showed a moderate gonadal development, but did not ripen until the next summer. Mullets of all ages gained weight only when the water temperature was higher than 20°C. However adults and immature fish showed reduced growth in mid-summer, when that of the juveniles peaked. This difference is not a consequence of the reproductive cost, because the growth rate of immatures was greatly reduced although they did not spawn.

Development of the femur - Implications for age and sex determination.

Growth of four variables of the femur (diapyseal length, diaphyseal length plus distal epiphysis, maximum length and vertical diameter of the head) was analyzed by polynomial regression for the purpose of evaluating its significance and capacity for age and sex determination throughout the entire life continuum. Materials included in analysis consisted of 346 specimens ranging from birth to 97 years of age from five documented osteological collections of Western European descent. Linear growth was displayed by each of the four variables. Significant sexual dimorphism was identified in two of the femoral measurements, including maximum length and vertical diameter of the head, from age 15 onward. These results indicate that the two variables may be of use in the determination of sex in sex determination from that age onward. Strong correlation coefficients were identified between femoral size and age for each of the four metric variables. These results indicate that any of the femoral measurements is likely to serve as a useful source to estimate sub-adult age in both archaeological and forensic samples.