Abundance and composition of small floating plastics in the eastern and southern sectors of the Atlantic Ocean.

We report the distribution of floating plastics in the eastern and southern sectors of the Atlantic Ocean based on 35 neuston net trawl samples collected during two research cruises in 2016 and 2017. Plastic particles (>200 µm) were found in 69% of net tows, with median densities of 1583 items·km-2 and 5.1 g·km-2. Most particles (80% of 158) were microplastics (<5 mm) of secondary origin (88%), followed by industrial pellets (5%), thin plastic films (4%) and lines/filaments (3%). Due to the large mesh size we used, textile fibers were not considered in this study. µFTIR analysis revealed that most particles found in the net were made of polyethylene (63%), followed by polypropylene (32%) and polystyrene (1%). A transect between 0 and 18°E along 35°S in the South Atlantic Ocean revealed higher densities farther west, supporting the accumulation of floating plastics in the South Atlantic gyre, mainly west of 10°E.

Analysis of gait patterns pre- and post- Single Event Multilevel Surgery in children with Cerebral Palsy by means of Offset-Wise Movement Analysis Profile and Linear Fit Method.

Gait analysis is used for the assessment of walking ability of children with cerebral palsy (CP), to inform clinical decision making and to quantify changes after treatment. To simplify gait analysis interpretation and to quantify deviations from normality, some quantitative synthetic descriptors were developed over the years, such as the Movement Analysis Profile (MAP) and the Linear Fit Method (LFM), but their interpretation is not always straightforward. The aims of this work were to: (i) study gait changes, by means of synthetic descriptors, in children with CP that underwent Single Event Multilevel Surgery; (ii) compare the MAP and the LFM on these patients; (iii) design a new index that may overcome the limitations of the previous methods, i.e. the lack of information about the direction of deviation or its source. Gait analysis exams of 10 children with CP, pre- and post-surgery, were collected and MAP and LFM were computed. A new index was designed asa modified version of the MAP by separating out changes in offset (named OC-MAP). MAP documented an improvement in the gait pattern after surgery. The highest effect was observed for the knee flexion/extension angle. However, a worsening was observed as an increase in anterior pelvic tilt. An important source of gait deviation was recognized in the offset between observed tracks and reference. OC-MAP allowed the assessment of the offset component versus the shape component of deviation. LFM provided results similar to OC-MAP offset analysis but could not be considered reliable due to intrinsic limitations. As offset in gait features played an important role in gait deviation, OC-MAP synthetic analysis was proposed as a novel approach to a meaningful parameterisation of global deviations in gait patterns of subjects with CP and gait changes after treatment.

A continuous loading apparatus for measuring three-dimensional stiffness of ankle-foot orthoses.

This paper describes a novel device to evaluate the mechanical properties of ankle foot orthoses (AFOs). The apparatus permits the application to AFOs of continuous three-dimensional (3D) movements between specified and settable endpoints. Using an x-y robot with a rotary stage and a six-component load cell, characteristic displacement versus reaction force curves can be generated and consequently the ankle moments can be determined as a function of dorsi/plantar flexion, inv/eversion and int/external rotation. Representative curves for two polypropylene lateral leaf AFOs, different in shape but produced for the same leg by a skilled orthotist, are presented to illustrate the capabilities of the novel testing system. The metrological investigation showed that the apparatus creates a highly repeatable data set (uncertainty < or = 1% FSO).