Energy efficiency analysis and design optimization of an actuation system in a soft modular lower limb exoskeleton

One of the critical aspects in the design of an assistive wearable robot is the energy efficiency of the actuation system, since it affects significantly the weight and consequently the comfort of the system. Several strategies have been used in previous research, mostly based on energy harvesting, compliant elements for mechanical energy accumulation (springs or elastic cords), ratchets and clutches. However, the design of the optimal actuator arrangement is highly dependent on the task, which increases significantly the complexity of the design process. In this work we present an energy efficiency analysis and design optimization of an actuation system applied to a soft module lower limb exoskeleton. Instead of performing a comparison between predefined mechanism arrangements, we solve a full optimization problem which includes not only the mechanism parameters, but also the mechanism architecture itself. The optimization is performed for a walking task using gait data from a stroke subject, and the result is a set of actuator Arrangements with optimal parameters for the analyzed task and selected user. The optimized mechanism is able to reduce the energy requirements by 20-65%, depending of the joint. The proposed mechanism is currently under development within the XoSoft EU project, a modular soft lower-limb exoskeleton to assist People with mobility impairments

Carga de enfermedad y económica atribuible al consumo de bebidas azucaradas en El Salvador

OBJECTIVE: To estimate the burden of disease and economic burden attributable to the consumption of sugar-sweetened beverages in El Salvador. METHODS: A comparative risk model was used to estimate the effects on deaths, health events, disability-adjusted life years (DALYs), and direct medical costs attributable to the consumption of sugar-sweetened beverages. RESULTS: A total of 520 deaths (8 per 100 000 individuals), 214 082 health events (3 220 per 100 000 individuals) and 16 643 DALYs could be attributable to the consumption of sugar-sweetened beverages in El Salvador, representing US$69.35 million in direct medical costs for the year 2020. In particular, type 2 diabetes (T2DM) events attributable to the consumption of sugar-sweetened beverages could represent more than 20% of total T2DM cases in the country. CONCLUSION: A high number of deaths, events, and costs could be attributed to the consumption of sugar-sweetened beverages in El Salvador

Health and economic burden of disease of sugar-sweetened beverage consumption in four Latin American and Caribbean countries : a modelling study

OBJECTIVE: Overweight and obesity are important contributors to the non-communicable disease burden. The consumption of sugar-sweetened beverages (SSBs) has been associated with an increased risk of type 2 diabetes mellitus (T2DM), cardiovascular disease, cancer and other conditions. The objective of this study was to estimate the burden of disease attributable to the consumption of SSBs and the costs to the healthcare systems in Argentina, Brazil, El Salvador, and Trinidad and Tobago. DESIGN: Following a systematic review of models, a comparative risk assessment framework was developed to estimate the health and economic impact associated with the consumption of SSBs. SETTING: Argentina, Brazil, El Salvador, and Trinidad and Tobago. PARTICIPANTS: Overall population. PRIMARY AND SECONDARY OUTCOME MEASURES: The model estimated the effects of SSB consumption on health through two causal pathways: one mediated by body mass index (BMI) and health conditions associated with BMI and another that reflected the independent effects of SSB consumption on T2DM and cardiovascular diseases. RESULTS: The model results indicated that for all four countries, in 1 year, SSB consumption was associated with 18 000 deaths (3.2% of the total disease-related deaths), seven million disease events (3.3% of the total disease-related events), a half-million DALYs and US$2 billion in direct medical costs. This included 1.5 million cases of overweight and obesity in children/adolescents (12% of the excess weight cases) and 2.8 million cases in adults (2.8%); 2.2 million cases of type 2 diabetes (19%); 200 000 cases of heart disease (3.8%); 124 000 strokes (3.9%); 116 000 cases of musculoskeletal disease (0.2%); 102 000 cases of kidney disease (0.9%); and 45 000 episodes of asthma (0.4%). The Trinidad and Tobago population were the most affected by disease events. CONCLUSIONS: The study results indicate that the consumption of SSBs is associated with a significant burden of disease and death in Latin America and the Caribbean

Clinical characteristics and risk factors associated with COVID-19 severity in patients with haematological malignancies in Italy: a retrospective, multicentre, cohort study

Several small studies on patients with COVID-19 and haematological malignancies are available showing a high mortality in this population. The Italian Hematology Alliance on COVID-19 aimed to collect data from adult patients with haematological malignancies who required hospitalisation for COVID-19

Resonant Acoustic Metamaterials

Acoustic applications of metamaterials have rapidly developed over the past few decades. The sound attenuation provided by metamaterials is due to the interaction between soundwaves and scatterers organized into a reticular grid, with a peak attenuation at a specific frequency band that is highly dependent on the scatterers’ diameter and reticular geometric organization of installation. In this article, the scatterer types chosen for the experiments are represented by a 2D shape, which are cylindrical solid-wood bars of 15 mm diameter and empty cylindrical bars of 20 mm diameter. Acoustic measurements were conducted in a semi-anechoic chamber to identify the specific frequency at which the highest insertion loss (IL) was registered. A second experiment was conducted by creating holes of 5 mm diameter on the external surface of the empty bars; in this way, it registered a higher sound attenuation. In particular, the resonant system characterized with holes, in combination with the attenuation given by 2D scatterer metamaterials, increased the sound attenuation for the frequency range between 1 kHz and 10 kHz

Soft Smart Garments for Lower Limb Joint Position Analysis

Revealing human movement requires lightweight, flexible systems capable of detecting mechanical parameters (like strain and pressure) while being worn comfortably by the user, and not interfering with his/her activity. In this work we address such multifaceted challenge with the development of smart garments for lower limb motion detection, like a textile kneepad and anklet in which soft sensors and readout electronics are embedded for retrieving movement of the specific joint. Stretchable capacitive sensors with a three-electrode configuration are built combining conductive textiles and elastomeric layers, and distributed around knee and ankle. Results show an excellent behavior in the ~30% strain range, hence the correlation between sensors’ responses and the optically tracked Euler angles is allowed for basic lower limb movements. Bending during knee flexion/extension is detected, and it is discriminated from any external contact by implementing in real time a low computational algorithm. The smart anklet is designed to address joint motion detection in and off the sagittal plane. Ankle dorsi/plantar flexion, adduction/abduction, and rotation are retrieved. Both knee and ankle smart garments show a high accuracy in movement detection, with a RMSE less than 4° in the worst case

Occurrence of L1M Elements in Chromosomal Rearrangements Associated to Chronic Myeloid Leukemia (CML): Insights from Patient-Specific Breakpoints Characterization

Chronic myeloid leukemia (CML) is a rare myeloproliferative disorder caused by the reciprocal translocation t(9;22)(q34;q11) in hematopoietic stem cells (HSCs). This chromosomal translocation results in the formation of an extra-short chromosome 22, called a Philadelphia chromosome (Ph), containing the BCR-ABL1 fusion gene responsible for the expression of a constitutively active tyrosine kinase that causes uncontrolled growth and replication of leukemic cells. Mechanisms behind the formation of this chromosomal rearrangement are not well known, even if, as observed in tumors, repetitive DNA may be involved as core elements in chromosomal rearrangements. We have participated in the explorative investigations of the PhilosoPhi34 study to evaluate residual Ph+ cells in patients with negative FISH analysis on CD34+/lin- cells with gDNA qPCR. Using targeted next-generation deep sequencing strategies, we analyzed the genomic region around the t(9;22) translocations of 82 CML patients and one CML cell line and assessed the relevance of interspersed repeat elements at breakpoints (BP). We found a statistically higher presence of LINE elements, in particular belonging to the subfamily L1M, in BP cluster regions of both chromosome 22 and 9 compared to the whole human genome. These data suggest that L1M elements could be potential drivers of t(9;22) translocation leading to the generation of the BCR-ABL1 chimeric gene and the expression of the active BCR-ABL1-controlled tyrosine kinase chimeric protein responsible for CML