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Terahertz imaging is unlocking unique capabilities for the analysis of cultural heritage artifacts. This paper uses terahertz time-domain imaging for the study of a gilded wooden artifact, providing a means to perform stratigraphic analysis, yielding information about the composition of the artifact, presence of certain materials identifiable through their THz spectral fingerprint, as well as alterations that have been performed over time. Due to the limited information that is available for many historic artifacts, the data that can be obtained through the presented technique can guide proper stewardship of the artifact, informing its long-term preservation. [ABSTRACT FROM AUTHOR]

Purpose: High-intensity aerobic interval training (AIT) has been reported to be more effective than continuous aerobic training (CoAT) to improve metabolic health. The aim of our study was to investigate whether moderate-intensity AIT is more effective than CoAT on metabolic health when applied to a walking training program. Design/Metliods: Thirty-two postmenopausal women (55.37 ± 3.46 years) were investigated for body composition, plasma glucose, insulin, lipids, adiponectin, HOMA-IR, HOMA-AD, aerobic fitness, dietary habits, and spontaneous physical activity, and randomly assigned to one of two different walking training programs: CoAT or AIT. Results: CoAT and AIT elicited the same physiological benefits, including: reduction of plasma glucose, insulin. HOMA-IR and HOMA-AD, and increase of plasma HDL-C, adiponectin, and aerobic fitness. Conclusions: An AIT scheme as part of an outdoor walking training program elicits the same physiological adaptations as a CoAT scheme, probably because walking does not promote exercise intensities that elicit greater effects. [ABSTRACT FROM AUTHOR]

New flame retardant organo-modified bentonites, based on nitrogen-containing compounds were synthesized via an ion exchange process starting from pristine bentonite with acidified 6-(4-butylphenyl)−1,3,5-triazine-2,4-diamine (BFTDA) and 11-amino- N-(pyridine-2yl)undecanamide (APUA). The amount of nitrogen rich organic modifier in the obtained organoclays (Bento-BFTDA and Bento-APUA) determined by TGA is around 0.4 mmol/g for both samples. With the aim to study the effect of these additives on a commercial epoxy resin, nanocomposites containing 3 and 5 wt% of the nanofillers were prepared by solventless addition to the epoxy resin formulation. For the sake of comparison similar nanocomposites with plain unmodified bentonite were produced. The nanocomposite's thermo-mechanical properties of all the produced samples were measured and they resulted slightly improved or practically unaffected. Finally, when the flame behavior was assessed in the cone-calorimeter, an encouraging decrease of 17% in the peak heat released rate (pHRR) was obtained at 3 wt% loading level with Bento-APUA. These promising results suggest that the APUA modified organoclay, prepared with low cost reactants and mild reaction conditions, might efficiently act as a flame retardant. POLYM. ENG. SCI., 57:621-630, 2017. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Summary Introduction Several studies have shown that activation of the sympathetic nervous system results in the increased secretion of α-amylase (sAA), an enzyme produced by salivary glands. Recently, chromogranin A (CgA), a soluble protein costored and coreleased with catecholamines from the adrenal medulla and sympathetic nerve endings, has been proposed as a marker of sympathoadrenal medullary system (SAM) activity. The aim of this study was to investigate the behaviour of salivary chromogranin A (sCgA) and sAA during high-intensity exercise and to analyse their possible correlation with cardiovascular and psychological parameters. Methods Before and during a standardized treadmill stress test, and at 5, 15 and 30 min during the recovery phase, sCgA and sAA were monitored in 21 healthy men. The double product (DP) of blood pressure and heart rate responses, and the product of the subjective ratings of perceived exertion recorded at the final step (RPE) and the exercise duration were used as indices of cardiovascular and exercise intensity, respectively. Results With respect to baseline, significant ( P < 0·001) increases in peak sCgA (median 64%) and sAA (median 86%) were observed at the end of exercise. During the recovery phase, sAA levels fell abruptly, whereas sCgA remained elevated ( P < 0·001). Significant correlations emerged only for sCgA with respect to %DP ( r = 0·84; P < 0·001) and last step-RPE ( r = 0·82; P = 0·024). Conclusions These data suggest sCgA as a reliable marker of SAM activation. Furthermore, the relationship between sCgA and exercise intensity highlights the potential use of this noninvasive parameter in monitoring the adrenergic response during intense physical stress. [ABSTRACT FROM AUTHOR]

Recent studies of human arm movements have suggested that the control of stiffness may be important both for maintaining stability and for achieving differences in movement accuracy. Several studies in the robotic field demonstrated that grasp stiffness is useful for modelling and controlling manipulators but, even though it is accredited that having models of the human finger impedance would be very desirable for the control of anthropomorphous robot's hands, relatively few studies have focused on finger and hand stiffness. To allow the measurement of such entities at the finger level, an appropriate device capable of applying fast force transients while at the same time be able to monitor the finger movements is required. The work presented in this paper is a very detailed report about the design of a new hand exoskeleton system that will be used in our future works to investigate the finger stiffness range in different grasping postures and conditions. [ABSTRACT FROM AUTHOR]

Antioxidant activity of native vitamin C (ascorbic acid, AH2) is hampered by instability in solution. Selective loading of AH2 into the inner lumen of natural halloysite nanotubes (HNT) yields a composite nanoantioxidant (HNT/AH2), which was characterized and investigated for its reactivity with the persistent 1,1-diphenyl-2-picrylhydrazyl (DPPH•) radical and with transient peroxyl radicals in the inhibited autoxidation of organic substrates, both in organic solution (acetonitrile) and in buffered (pH 7.4) water in comparison with native AH2. HNT/AH2 showed excellent antioxidant performance being more effective than native ascorbic acid by 131% in acetonitrile and 290% (three-fold) in aqueous solution, under identical settings. Reaction with peroxyl radicals has a rate constant of 1.4 × 106 M−1 s−1 and 5.1 × 104 M−1 s−1, respectively, in buffered water (pH 7.4) and acetonitrile, at 30 °C. Results offer physical understanding of the factors governing HNT/AH2 reactivity. Improved performance of HNT/AH2 is unprecedented among forms of stabilized ascorbic acid and its relevance is discussed on kinetic grounds. [ABSTRACT FROM AUTHOR]

Background: Forearm surface electromyography (EMG) has been in use since the Sixties to feed-forward control active hand prostheses in a more and more refined way. Recent research shows that it can be used to control even a dexterous polyarticulate hand prosthesis such as Touch Bionics's i-LIMB, as well as a multifingered, multi-degree-of-freedom mechanical hand such as the DLR II. In this paper we extend previous work and investigate the robustness of such fine control possibilities, in two ways: firstly, we conduct an analysis on data obtained from 10 healthy subjects, trying to assess the general applicability of the technique; secondly, we compare the baseline controlled condition (arm relaxed and still on a table) with a "Daily-Life Activity" (DLA) condition in which subjects walk, raise their hands and arms, sit down and stand up, etc., as an experimental proxy of what a patient is supposed to do in real life. We also propose a cross-subject model analysis, i.e., training a model on a subject and testing it on another one. The use of pre-trained models could be useful in shortening the time required by the subject/patient to become proficient in using the hand.Results: A standard machine learning technique was able to achieve a real-time grip posture classification rate of about 97% in the baseline condition and 95% in the DLA condition; and an average correlation to the target of about 0.93 (0.90) while reconstructing the required force. Cross-subject analysis is encouraging although not definitive in its present state.Conclusion: Performance figures obtained here are in the same order of magnitude of those obtained in previous work about healthy subjects in controlled conditions and/or amputees, which lets us claim that this technique can be used by reasonably any subject, and in DLA situations. Use of previously trained models is not fully assessed here, but more recent work indicates it is a promising way ahead. [ABSTRACT FROM AUTHOR]