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We aimed to analyse cardiac autonomic control by assessing the post-exercise heart rate recovery (HRR) and physical fitness in children and adolescents with spina bifida (SB), compared to participants with typical development. A total of 124 participants, 42 with spina bifida (SB group) and 82 typical developmental controls (CO group) performed the arm cranking exercise test with a gas analysis system. HRR was determined at the first (HRR_1) and second (HRR_2) minute at recovery phase. Data are shown as [mean difference (95% CI)]. The SB group showed reduced HR reserve [14.5 (7.1–22.0) bmp, P<0.01], slower HRR_1 [12.4 (7.4–17.5) bpm, P<0.01] and HRR_2 [16.3 (10.6–21.9) bpm; P<0.01], lower VO2peak [VO2peak relative: 7.3 (4.2–10.3) mL·min−1 ·kg−1 , P<0.01; VO2peak absolute: 0.42 (0.30–0.54) L·min−1 , P<0.01], and lower O2 pulse [2.5 (1.8–3.2) mL·bpm, P<0.01] and ventilatory responses [13.5 (8.8–18.1) L·min−1 , P<0.01] than the CO group. VE/VO2 was not different between groups [−2.82 (−5.77– −0.12); P=0.06], but the VE/VCO2 [−2.59 (−4.40–0.78); P<0.01] and the values of the anaerobic threshold corrected by body mass [−3.2 (−5.8– −0.6) mL·min−1 ·kg−1 , P=0.01] were higher in the SB group than in the CO group. We concluded that children and adolescents with SB have reduced physical fitness and a slower HRR response after maximal effort. [ABSTRACT FROM AUTHOR]

To perform a cross-cultural adaptation of the OMNI verbal descriptors to Brazilian-Portuguese and examine the validity of the Brazilian version for arm-crank activity. Cross-cultural adaptation stages were: permission, translation, synthesis, back translation, expert committee review, pretesting, and submission and appraisal. For the concurrent validity, a Brazilian OMNI-Wheel scale was used to obtain rating of perceived exertion for the overall body (RPEOverall) and arms (RPEArms) in participants (n = 9, 10–17 years) with spina bifida. Cardiopulmonary exercise test was used to measure heart rate (HR) and oxygen uptake (VO2). Repeated Measures Correlation (rrm) was used to examine the scale validity. The cross-cultural adaptation produced equivalence between English and Brazilian-Portuguese verbal descriptors based on successful translation and pretesting. The Brazilian OMNI-wheel was validated based on strong associations of RPEOverall with VO2 (rrm (35) = 0.86, 95% CI [0.93, 0.73], p < 0.001) and HR (rrm (35) = 0.89, 95% CI [0.94, 0.79], p < 0.001) and RPEArms with VO2 (rrm (33) = 0.82, 95% CI [0.91, 0.66], p < 0.001) and HR (rrm (33) = 0.82, 95% CI [0.91, 0.66], p < 0.001). The OMNI scale was cross-culturally adapted to Brazilian-Portuguese. The Brazilian OMNI-Wheel was validated based on strong associations of RPE with HR and VO2. The original English OMNI was cross-culturally adapted to Brazilian-Portuguese. A Brazilian wheelchair OMNI was concurrently validated for Arm-Crank Activity in adolescents with spina bifida. This OMNI scale version may aid health providers in monitoring perceived exertion in Brazil. [ABSTRACT FROM AUTHOR]

New leather treatment processes involving nanoparticles require new testing methods and procedures to evaluate their impact on human health. In the current work, the tribological properties of goat leather surfaces with sputter deposited Ti-Ag-O films were analyzed. A set of different polymer counter bodies was used to establish different tribological contact situations. A detailed analysis of the worn surfaces by scanning electron microscopy revealed details about the wear mechanisms ranging from abrasive to adhesive depending on the friction. Further, information about the formation of wear debris particles from the Ti-Ag-O films was obtained, in particular whether or not these particles were transferred to the counter body. The performed tests exemplify a possible testing procedure for leather treated with nanoparticles. • Coated leather surface exposed to different tribological contact situations. • Wear behavior and formation of wear debris particles analyzed. • Adhesive wear at high friction conditions favors transfer of wear debris to counter body. [ABSTRACT FROM AUTHOR]

CrAlN and CrAlSiN hard coatings deposited by magnetron sputtering were analyzed for their high temperature mechanical and tribological properties. High temperature nanoindentation measurements on both coatings were performed from room temperature up to 700 °C in steps of 100 °C where a reduction in hardness H and elastic modulus E* from their initial values was noticed. In addition, high temperature tribological tests were conducted in inert atmosphere in the same temperature range to obtain information about the coefficient of friction and the wear coefficient. In order to link the tribological behavior to the obtained mechanical properties, the H/E* ratio was calculated and compared to the high temperature wear from the current and other studies with similar coatings. The evolution of the mechanical and tribological properties at high temperature is discussed based on the current knowledge available in literature. • CrAlN and CrAlSiN coatings reveal similar decrease in hardness up to deposition temperature. • Different evolution in mechanical properties at temperatures above deposition temperature • CrAlSiN shows superior friction and wear behavior at high temperature. • Increased wear with decreasing H/E* ratio at high temperature for both coatings • Critical H/E* marking strong increase in wear in the range of 0.08 to 0.085 [ABSTRACT FROM AUTHOR]

Highlights • Children and adolescents with myelomeningocele showed higher heart rate at rest. • Children and adolescents with myelomeningocele did not show differences in HR and BP variability. • Children and adolescents with myelomeningocele showed lower baroreflex sensitivity. Abstract Background Cardiovascular autonomic dysfunction is associated with the development of cardiovascular diseases, but little is known about it in children and adolescents with myelomeningocele. Objective This study investigated the cardiovascular autonomic function in wheelchair-using children and adolescents with myelomeningocele. Methods Twenty-two participants were assigned to one of two groups: myelomeningocele group (n = 11) and Control group (n = 11). Heart rate variability and systolic blood pressure variability were collected in supine resting position using spectral analyses. Spontaneous baroreflex sensitivity was collected by time-domain through the sequence method. Results At rest, heart rate was higher in myelomeningocele group when compared to Control group (mean difference 22.1, 95% CI 4.82–39.40; p = 0.01). The heart rate and systolic blood pressure variability parameters did not show differences between groups. However, myelomeningocele showed lower gain mean in baroreflex sensitivity (mean difference −4.5, 95% CI −8.47 to −0.60; p = 0.02), when compared to Control. Conclusion Wheelchair-using children and adolescents with myelomeningocele presented differences in the autonomic cardiovascular function. This may be associated with hypomobility due to wheelchair dependence, and venous muscle pump insufficiency due to paraplegia. [ABSTRACT FROM AUTHOR]

Propulsive wheelchair capacity may be influenced by arm muscle performance. Objectives: To determine whether children and adolescent wheelchair-users with spina bifida show reduced arm muscle strength compared to their typically developing peers and to compare muscle strength data obtained by isokinetic and handheld dynamometry (HHD). Participants (mean age 12.5 ± 2.5 years) were assigned to spina bifida (SB; n = 11) or control (n = 22) groups. Isokinetic dynamometry was used to measure peak torque (PT) during dynamic (60°s−1 and 120°s−1) and isometric strength testing (MVIC) for shoulder and elbow flexors and extensors. HHD was used to measure MVIC of the same muscle groups. SB showed reduced isokinetic PT for shoulder extensors at 60°s−1 and 120°s−1, shoulder flexor MVIC, and elbow flexors at 60°s−1 and MVIC; higher PT for shoulder flexors and elbow flexors at 120°s−1; and decreased MVIC for elbow flexors but not extensors compared to controls when assessed by HHD. The SB and control groups showed strong positive correlations between MVIC data obtained by the two devices for all muscle groups (r ≥ 0.81; p <.01), except for shoulder flexor MVIC in controls (r = 0.68; p <.01). SB presented reduced levels of dynamic slow-speed and isometric shoulder and elbow muscle strength and greater dynamic high-speed shoulder and elbow flexor strength than controls possibly due to the exposure to self-sustained wheelchair ambulation. Exercise-based intervention protocols to increase slow-speed arm muscle strength should be considered in youth with SB. Strong positive correlations observed between muscle strength assessed by isokinetic dynamometry and HHD support the use of HHD in this clinical population. [ABSTRACT FROM AUTHOR]

Highlights • Boys develop more pronounced isometric muscular strength starting at 10 years of age and it peaks at 14 and 15 years. • The Handheld dynamometer has excellent inter-rater reliability and an intra-rater agreement for all muscle groups tested. • The development of muscle strength for the Brazilian population is similar to that observed in the northern hemisphere. Abstract Objective Isometric muscle strength measured by Handheld dynamometer indicates physical ability. There is no normative data for the Brazilian population. This study aims (a) to describe the development of isometric muscle strength in healthy children and adolescents 5–15 years of age; (b) to evaluate Handheld dynamometer inter and intra-rater reliability. Methods Isometric muscle strength was obtained for shoulder abduction, elbow and knee flexion and extension, dorsiflexion and plantar flexion in 55 boys and 55 girls, aged between 5 and 15 years. Inter-rater reliability was determined based on the evaluation of 2 raters, with a 20-min interval between them. Intra-rater reliability was based on 2 evaluations from the same rater, one week apart. Interclass correlation coefficient (ICC 2,1; 3,1), Bland Altman plots and linear regression models with mixed effects were used to quantify inter and intra-rater reliability, agreement and associations with physical activity level and maturational factors. Results A linear development of isometric muscular strength was observed for ages between 5 and 10. After age 10, boys showed a larger isometric muscular strength, when compared to girls. Both inter and intra-rater measurements of the Handheld dynamometer are reliable (ICC > 0.63). Conclusions This study shows increase in isometric muscle strength starting at 10 years of age for boys, when compared to girls and inter and intra-rater reliability for the assessment of isometric strength, using the Handheld dynamometer for the muscle groups tested on the dominant and non-dominant side, for children between 5 and 15 years of age. [ABSTRACT FROM AUTHOR]

Hard coatings grown by physical vapor deposition (PVD) or chemical vapor deposition (CVD) on cutting tools are applied to considerably increase the tools' performance and lifetime. Besides differences in types, thicknesses, structures and properties of the coatings synthesized by PVD and CVD, the deposition processes differ significantly in their throughput of tools as well as their energy and material consumption. Within this work, a methodology to analyze the energy and material fluxes of typical PVD and CVD processes for the deposition of hard coatings on cutting tools is introduced. Three case studies are considered: ( i ) cathodic arc evaporation of TiCN, ( ii ) magnetron sputter deposition of TiN, and ( iii ) CVD of a TiCN/Al 2 O 3 bilayer coating. The material fluxes and energy consumption for each process step of the respective deposition processes were monitored and are illustrated by individual Sankey diagrams. The visualization by Sankey diagrams allows to readily identify the main energy and mass consuming process steps. Finally, a normalization procedure enabling the comparison of different hard coating production routes is presented and discussed. [ABSTRACT FROM AUTHOR]

Background Orthosis use prevents muscle contracture and prolongs ambulation in patients with Duchenne muscular dystrophy (DMD). However, its biomechanical effects on gait are unclear. This study assessed the effects of daytime and night-time use of Articulated Ankle Foot Orthosis (AFO) on kinematic, kinetic and spatial/temporal gait parameters of DMD patients. Methods Twenty ambulatory patients (4–12 years of age) were assigned to one of three groups: no orthosis (NoO; n = 7), night-time orthosis (NiO; n = 7), day-time orthosis (DO; n = 6). All subjects were evaluated once (Ev1) and five of them were re-evaluated between five and seven months after Ev1 (Ev2). Findings Cross-sectional analysis with linear mixed-effects models (ANOVA) showed increased peak dorsiflexion angle and dorsiflexor moment and decreased plantar flexion angle and ankle joint power generation for the DOwith group when compared to the NoO group ( P < 0.05). The DOwith group also showed decreased peak hip flexion angle, hip power absorption, plantar flexion angle and increased peak dorsiflexion moment when compared to the NoO group ( P < 0.05). Analysis of gait cycle curves showed significant and clinically relevant changes in kinematic and kinetic parameters for the DOwith group when compared to the other experimental groups. Longitudinal analysis suggest that night-time use of Articulated AFO can promote positive changes in gait parameters of DMD patients, when used before the functional deficit is too advanced. Interpretation Early daytime and night-time use of Articulated AFO changed gait and minimized typical compensations seen in DMD patients, thus it is recommended in order to prolong gait ability. [ABSTRACT FROM AUTHOR]

This paper looks at the extraction of trends of household electrical seasonal consumption via load disaggregation. With the proviso that data for several home devices can be embedded in a tensor, non-negative multi-way array factorization is performed in order to extract the most relevant components. In the initial decomposition step the decomposed signals are incorporated in the test signal consisting of the whole-home measured consumption. After this the disaggregated data corresponding to each electrical device is obtained by factorizing the associated matrix through the learned model. Finally, we evaluate the performance of load disaggregation by the supervised method, and study the trends along several years and across seasons. Towards this end, computational experiments were yielded using real-world data from household electrical consumption measurements along several years. While breaking down the whole house energy consumption into appliance level gives less accurate estimates in the late years, we empirically show the adequacy of this method for handling the earlier years and the estimates of the underlying seasonal trend-cycle. [ABSTRACT FROM AUTHOR]

Nanoindentation measurements at elevated temperatures were performed on α-Al 2 O 3 and κ-Al 2 O 3 hard coatings at temperatures up to 600 and 700 °C, respectively. A reduction of the hardness and reduced modulus was observed for both coating systems although more accentuated for the κ-Al 2 O 3 coating. In addition, a comprehensive overview of guidelines on how to perform nanoindentation measurements on hard coatings at elevated temperatures is provided. [ABSTRACT FROM AUTHOR]

Measuring the electrical consumption of individual appliances in a household has recently received renewed interest in the area of energy efficiency research and sustainable development. The unambiguous acquisition of information by a single monitoring point of the whole house's electrical signal is known as energy disaggregation or nonintrusive load monitoring. A novel way to look into the issue of energy disaggregation is to interpret it as a single-channel source separation problem. To this end, we analyze the performance of source modeling based on multiway arrays and the corresponding decomposition or tensor factorization. First, with the proviso that a tensor composed of the data for the several devices in the house is given, nonnegative tensor factorization is performed in order to extract the most relevant components. Second, the outcome is later embedded in the test step, where only the measured consumption over the whole home is available. Finally, the disaggregated data by the device is obtained by factorizing the associated matrix considering the learned models. In this paper, we compare this method with a recent approach based on sparse coding. The results are obtained using real-world data from household electrical consumption measurements. The analysis of the comparison results illustrates the relevance of the multiway array-based approach in terms of accurate disaggregation, as further endorsed by the statistical analysis performed. [ABSTRACT FROM AUTHOR]

Abstract: Electrical load disaggregation for end-use recognition in the smart home has become an area of study of its own right. The most well-known examples are energy monitoring, health care applications, in-home activity modeling, and home automation. Real-time energy-use analysis for whole-home approaches needs to understand where and when the electrical loads are spent. Studies have shown that individual loads can be detected (and disaggregated) from sampling the power at one single point (e.g. the electric service entrance for the house) using a non-intrusive load monitoring (NILM) approach. In this paper, we focus on the feature extraction and pattern recognition tasks for non-intrusive residential electrical consumption traces. In particular, we develop an algorithm capable of determining the step-changes in signals that occur whenever a device is turned on or off, and which allows for the definition of a unique signature (ID) for each device. This algorithm makes use of features extracted from active and reactive powers and power factor. The classification task is carried out by Support Vector Machines and 5-Nearest Neighbors methods. The results illustrate the effectiveness of the proposed signature for distinguishing the different loads. [Copyright &y& Elsevier]

The optic disc melanocytoma is a benign tumor, with little predisposition to become a melanoma. It is usually asymptomatic, nonetheless should be evaluated periodically, most often by computerized perimetry, which in 9 out of 10 cases will show some alteration. In the following paper we report the case of 61 years old man without previous diagnosis of optic disc melanocytoma and discuss the importance of melanoma differential diagnosis and monitoring. [ABSTRACT FROM AUTHOR]

Hardness and toughness are among of the most important physical properties of hard coatings and it is important to analyze them at temperatures present during coating applications. CrAlN and CrAlSiN are hard coating materials frequently used in high temperature applications. While both possess high oxidation resistance and thermal stability, they differ in their microstructure. In this work, the fracture toughness of magnetron-sputtered single-layer CrAlN and CrAlSiN hard coatings was determined up to 700 °C by in-situ scanning electron microscopy micro-cantilever deflection tests. The results show a decreasing trend of the fracture toughness with increasing temperature. While both coatings' fracture toughness trends are similar up to 400 °C, they diverge at higher temperatures. In general, the evolution of the fracture toughness with increasing temperature shows similarities to the observed changes in hardness in the same temperature range. • CrAlN and CrAlSiN coatings fracture toughness decreases with increasing temperature. • Both coatings reveal similar fracture toughness trend below deposition temperature. • CrAlSiN shows better fracture toughness behavior at high temperature. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate the use of ultrahigh-speed volumetric en face and cross-sectional optical coherence tomography (OCT) with micromotor catheters for the in vivo assessment of Barrett's esophagus and dysplasia.Methods: 74 OCT datasets with correlated biopsy/endoscopic mucosal resection histology (49 nondysplastic Barrett's esophagus [NDBE], 25 neoplasia) were obtained from 14 patients with Barrett's esophagus and a history of dysplasia and 30 with NDBE. The associations between irregular mucosal patterns on en face OCT, absence of mucosal layering, surface signal > subsurface, and > 5 atypical glands on cross-sectional OCT vs. histology and treatment history were assessed by three blinded readers.Results: Atypical glands under irregular mucosal patterns occurred in 75 % of neoplasia (96 % of treatment-naïve neoplasia) vs. 30 % of NDBE datasets (43 % of short- and 18 % of long-segment NDBE). Mucosal layering was absent in 35 % of neoplasia and 50 % of NDBE datasets, and surface signal > subsurface occurred in 29 % of neoplasia and 30 % of NDBE datasets.Conclusions: Atypical glands under irregular mucosal patterns are strongly associated with neoplasia, suggesting potential markers for dysplasia and a role in pathogenesis. [ABSTRACT FROM AUTHOR]

In flexible and/or wearable electronics the thin films deposited on compliant substrates are not only subjected to straining and bending but also to tribological loading conditions. A frequently used method to assess tribological properties of materials systems is the ball-on-disc test. In the current work, Mo films were deposited by high power impulse magnetron sputtering on polyimide substrates to serve as a model system. To establish different tribological contact conditions, a series of different counterpart materials was chosen for the performed ball-on-disc tests. A detailed analysis by 3D confocal laser scanning microscopy and scanning electron microscopy revealed details about the wear mechanisms active during sliding where mainly abrasion of the softer one of the material pair was noticed. The obtained results for friction and wear together with the performed simulations of the induced stresses due to the loading conditions show that ball-on-disc tests can contribute to the understanding of the tribological response of metallic films on compliant substrates which in turn may help to improve the lifetime of components in flexible and/or wearable electronic applications. [ABSTRACT FROM AUTHOR]

Two main nonsurgical endoscopic approaches for ablating dysplastic and early cancer lesions in the esophagus have gained popularity, namely, radiofrequency ablation (RFA) and cryospray ablation (CSA). We report a uniquely suited endoscopic and near-microscopic imaging modality, three-dimensional (3D) optical coherence tomography (OCT), to assess and compare the esophagus immediately after RFA and CSA. The maximum depths of architectural changes were measured and compared between the two treatment groups. RFA was observed to induce 230∼260 μm depth of architectural changes after each set of ablations over a particular region, while CSA was observed to induce edema-like spongiform changes to ∼640 μm depth within the ablated field. The ability to obtain micron-scale depth-resolved images of tissue structural changes following different ablation therapies makes 3D-OCT an ideal tool to assess treatment efficacy. Such information could be potentially used to provide real-time feedback for treatment dosing and to identify regions that need further retreatment. [ABSTRACT FROM AUTHOR]