The bipedal saddle space: modelling and validation.

Better understanding of human balance control is pivotal for applications such as bipedal robots and medical technologies/therapies targeting human locomotion. Despite the inverted pendulum model being popular for describing bipedal locomotion, it does not properly capture the step-to-step transition dynamics. The major drawback has been the requirement for both feet to be on the ground which generates a discontinuity along the intersection of the potential energy surfaces produced by the two legs. To overcome this problem, we propose a generalized inverted pendulum-based model that can describe both single and double support phases. The full characterization of the system's potential energy allows the proposed model to drop the main limitation. This framework also enables optimal strategies to be designed for the transition between the two feet without the optimization algorithms. The proposed theory has been validated by comparing the human locomotor strategies output of our planner with real data from multiple experimental studies. The results show that our model generates trajectories consistent with human variability and performs better than existing well-known methods.

Declining incidence of intracerebral hemorrhage over two decades in a population-based study.

BACKGROUND AND PURPOSE: The incidence and case-fatality rate (CFR) of primary intracerebral hemorrhage (PICH) over two decades were assessed in a prospective population-based study. METHODS: Cases of incident first-ever PICH were recorded over a 2-year period (2011-2012) from multiple sources in the district of L'Aquila, central Italy. Included patients were followed up to 1 year after the event to ascertain CFRs. Current data were compared with those previously collected from 1994 through 1998. RESULTS: In all, 115 patients (52 men; 45.2%) with a first-ever PICH were included. Mean age ± SD was 77.4 ± 11.8 years. The hemorrhage was lobar in 43 (37.4%) patients, deep in 56 (48.7%), in the posterior fossa in 11 (9.6%) and intraventricular or multiple localized in five (4.3%). Crude annual incidence rate was 19.3 per 100 000 and 14.8 per 100 000 when standardized to the 2011 European population, indicating a 48% reduction comparing data of 2011-2012 to those of 1994-1998 (incidence rate ratio 0.52; 95% confidence interval 0.43-0.64; P < 0.001). In 2011-2012, the 7-day CFR was 27.8%, the 30-day CFR was 42.6% and the 1-year CFR was 52.2%; the 1-year standardized mortality ratio was 0.81 (95% confidence interval 0.63-1.04) compared with 1994-1998. CONCLUSIONS: The annual incidence rate of PICH was lower than that found two decades before and close to the rates recently found in other western countries. Data also indicated a non-significant trend towards a decrease in mortality, which nonetheless remained high, pointing to the need for more appropriate treatments in order to reduce PICH severity and mortality.

Migraine and risk of ischaemic heart disease: a systematic review and meta-analysis of observational studies.

BACKGROUND AND PURPOSE: Several studies have assessed the risk of ischaemic heart diseases in migraineurs, drawing different conclusions. To define and update the issue, a systematic review and meta-analysis of the available observational studies was performed. METHODS: PubMed and EMBASE were systematically searched up to April 2014 for observational studies dealing with the risk of any form of ischaemic heart disease in migraineurs. Studies assessing migraine as exposure and several types of ischaemic heart disease as outcomes were included in the analysis. A random effects model was used to pool the effect sizes. RESULTS: Out of 3348 records, 15 studies (one case-control, one cross-sectional and 13 cohort studies) were identified and were included in the meta-analysis. The pooled analysis indicated an increased risk of myocardial infarction (pooled adjusted effect estimate 1.33, 95% confidence interval 1.08-1.64; P = 0.007) and of angina (pooled adjusted effect estimate 1.29, 95% confidence interval 1.17-1.43; P < 0.0001) in migraineurs compared to non-migraineurs. CONCLUSIONS: Based on our data indicating an association of migraine with myocardial infarction and angina and on previous data showing an association of migraine, and particularly migraine with aura, with an increased risk for stroke, migraine can be appropriately considered an overall risk factor for cardiovascular diseases.