THE KNEE KINEMATICAL COORDINATION INVESTIGATION OF AN IMC CHILD DURING GAIT

International audienceCerebral palsy patients (cerebral infirm motor or IMC in French) present kinematical and kinetic differences with normal subjects and between their own left/right sides. These kinematical differences can be in relation with segmental coordination differences. The aim of this study is to characterize such segmental organization between the shank and the thigh for a cerebral palsy child in order to compare this coordination between left/right sides with the method of relative phase. A population of healthy subject let to validate our method with Byrne et al.'s results [1]. A young cerebral palsy child constitutes our clinical population for this study. A motion capture system (Vicon250) was used in order to capture movements of shank and thigh in sagittal plane. All the subjects walk at their self-selected speed along a horizontal walkway (9m). The angular position and angular velocity (calculated from position) of the shank and the thigh are computed as Byrne et al. After validation of our healthy results with Byrne et al's ones, we can describe the patient's curves. For him, the same path is observed between left and right sides. However, right side globally leads the left side. An important part of the stance phase presents the same temporal organization between these two sides

Mechanisms of life-course socioeconomic inequalities in adult systemic inflammation: Findings from two cohort studies

Disadvantaged socioeconomic conditions in childhood heighten systemic inflammatory levels in adulthood; however, life-course mechanisms underlying this association are largely unknown. In the present observational study, we investigated the roles of adulthood socioeconomic and lifestyle factors in mediating this association. Participants were from two prospective Swiss population-based cohorts (N = 5,152, mean age 60 years). We estimated the total effect of paternal occupational position on adult heightened systemic inflammatory levels (C-reactive protein>3 mg/L), and the indirect effects via adulthood socioeconomic positions (SEPs: education and occupational position), financial hardship, and lifestyle factors (body mass index, smoking status, physical inactivity, and alcohol consumption). We estimated odds ratio (OR) and proportion mediated using counterfactual-based mediation models. Individuals whose father had a low occupational position had an OR of 1.51 [95% confidence interval (CI): 1.25, 1.84] for heightened inflammation compared to their more advantaged counterparts. This was jointly mediated (33 [95% CI: 14, 69]%) by adulthood SEPs, whereby the pathway through education followed by occupational position mediated 30 [95% CI: 11, 64]%, while the pathway via occupational position only mediated 3 [95% CI: 4, 13]%. Individuals with the lowest life-course SEPs had an OR of 2.27 [95% CI: 1.71, 2.98] for heightened inflammation compared to having the highest life-course SEPs. This was jointly mediated (63 [95% CI: 44, 97]%) by financial hardship and lifestyle factors. Our study supports a cumulative effect of life-course SEPs on adult heightened systemic inflammation along the pathway paternal occupational position -> education -> adult occupational position. Financial hardship and lifestyle factors in adulthood mediate half of that effect

XPAD: pixel detector for material sciences

Currently available 2D detectors do not make full use of the high flux and high brilliance of third generation synchrotron sources. The XPAD prototype, using active pixels, has been developed to fulfil the needs of materials science scattering experiments. At the time, its prototype is build of eight modules of eight chips. The threshold calibration of /spl ap/4 10/sup 4/ pixels is discussed. Applications to powder diffraction or SAXS experiments prove that it allows to record high quality data

A pixel detector for the '95 upgrade of the DELPHI Micro Vertex Detector

pas de resum

Potassium limitation of forest productivity – Part 2: CASTANEA-MAESPA-K shows a reduction in photosynthesis rather than a stoichiometric limitation of tissue formation

Potassium (K) availability constrains forest productivity. Brazilian eucalypt plantations are a good example of the K limitation of wood production. Here, we built upon a previously described model (CASTANEA-MAESPA-K) and used it to understand whether the simulated decline in C source under K deficiency was sufficient to explain the K limitation of wood productivity in Brazilian eucalypt plantations. We developed allocation schemes for both C and K and included these in CASTANEA-MAESPA-K. Neither direct limitations of the C-sink activity nor direct modifications of the C allocation by K availability were included in the model. Simulation results show that the model was successful in replicating the observed patterns of wood productivity limitation by K deficiency. Simulations also show that the response of net primary productivity (NPP) is not linear with increasing K fertilisation. Simulated stem carbon use and water use efficiencies decreased with decreasing levels of K availability. Simulating a direct stoichiometric limitation of NPP or wood growth was not necessary to reproduce the observed decline of productivity under K limitation, suggesting that K stoichiometric plasticity could be different to that of N and P. Confirming previous results from the literature, the model simulated an intense recirculation of K in the trees, suggesting that retranslocation processes were essential for tree functioning. Optimal K fertilisation levels calculated by the model were similar to nutritional recommendations currently applied in Brazilian eucalypt plantations, paving the way for validation of the model at a larger scale and of this approach for developing decision-making tools to improve fertilisation practices.</p

Clinical features, risk factors, and impact of antibiotic treatment of diarrhea caused by Shigella in children less than 5 years in Manhiça District, rural Mozambique

Objectives: During the period from December 2007 to November 2012, the epidemiology of diarrhea caused by Shigella was studied among children <5 years of age residing in Manhiça District, Southern Mozambique. Materials and methods: Children from 0 to 5 years with moderate-to-severe diarrhea (MSD) and less severe diarrhea (LSD) were enrolled along with matched controls (by age, gender, and neighborhood). Age-stratified logistic regression analyses were conducted to identify clinical features and risk factors associated with Shigella positivity in cases of diarrhea. The impact of antibiotic treatment was assessed for patients with known outcome. Results: A total of 916 cases of MSD and 1979 matched controls, and 431 cases of LSD with equal number of controls were enrolled. Shigella was identified as significant pathogen in both cases of MSD and LSD compared to their respective controls. Shigella was detected in 3.9% (17/431) of LSD compared to 0.5% (2/431) in controls (P=0.001) and in 6.1% (56/916) of MSD cases compared to 0.2% (4/1979) in controls (P<0.0001), with an attributable fraction of 8.55% (95% CI: 7.86–9.24) among children aged 12–23 months. Clinical symptoms associated to Shigella among MSD cases included dysentery, fever, and rectal prolapse. Water availability, giving stored water to child, washing hands before preparing baby’s food, and mother as caretaker were the protective factors against acquiring diarrhea caused by Shigella. Antibiotic treatment on admission was associated with a positive children outcome. Conclusion: Shigella remains a common pathogen associated with childhood diarrhea in Mozambique, with dysentery being a significant clinical feature of shigellosis. Adherence to the basic hygiene rules and the use of antibiotic treatment could contribute to the prevention of most of diarrhea due to Shigella

Allostatic load and subsequent all-cause mortality: which biological markers drive the relationship? Findings from a UK birth cohort

The concept of allostatic load (AL) refers to the idea of a global physiological ‘wear and tear’ resulting from the adaptation to the environment through the stress response systems over the life span. The link between socioeconomic position (SEP) and mortality has now been established, and there is evidence that AL may capture the link between SEP and mortality. In order to quantitatively assess the role of AL on mortality, we use data from the 1958 British birth cohort including eleven year mortality in 8,113 adults. Specifically, we interrogate the hypothesis of a cumulative biological risk (allostatic load) reflecting 4 physiological systems potentially predicting future risk of death (N = 132). AL was defined using 14 biomarkers assayed in blood from a biosample collected at 44 years of age. Cox proportional hazard regression analysis revealed that higher allostatic load at 44 years old was a significant predictor of mortality 11 years later [HR = 3.56 (2.3 to 5.53)]. We found that this relationship was not solely related to early-life SEP, adverse childhood experiences and young adulthood health status, behaviours and SEP [HR = 2.57 (1.59 to 4.15)]. Regarding the ability of each physiological system and biomarkers to predict future death, our results suggest that the cumulative measure was advantageous compared to evaluating each physiological system sub-score and biomarker separately. Our findings add some evidence of a biological embodiment in response to stress which ultimately affects mortality.</p

Adverse childhood experiences and premature all-cause mortality

Events causing stress responses during sensitive periods of rapid neurological development in childhood may be early determinants of all-cause premature mortality. Using a British birth cohort study of individuals born in 1958, the relationship between adverse childhood experiences (ACE) and mortality ≤50 year was examined for men (n = 7,816) and women (n = 7,405) separately. ACE were measured using prospectively collected reports from parents and the school: no adversities (70 %); one adversity (22 %), two or more adversities (8 %). A Cox regression model was carried out controlling for early life variables and for characteristics at 23 years. In men the risk of death was 57 % higher among those who had experienced 2+ ACE compared to those with none (HR 1.57, 95 % CI 1.13, 2.18, p = 0.007). In women, a graded relationship was observed between ACE and mortality, the risk increasing as ACE accumulated. Women with one ACE had a 66 % increased risk of death (HR 1.66, 95 % CI 1.19, 2.33, p = 0.003) and those with ≥2 ACE had an 80 % increased risk (HR 1.80, 95 % CI 1.10, 2.95, p = 0.020) versus those with no ACE. Given the small impact of adult life style factors on the association between ACE and premature mortality, biological embedding during sensitive periods in early development is a plausible explanatory mechanism