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Comparing the rates of absorption and weight loss during a desorption test using near infrared spectroscopy
The importance of determining skin hydration has over the years prompt the development of many instruments and methods, specifically designed to assess this parameter or water contents especially in the stratum corneum, and have greatly matured to suit different anatomical sites and measure multiple attributes. Of those, Near Infrared Spectroscopy (NIRS) has gained wide interest as a precise, safe, fast and noninvasive technique for determining skin hydration due to its high sensitivity to hydrogen bonding and ability to measure the amount of water in skin directly using the intensities of overtone and combination bands of OH and HOH water bonds occurring in the NIR region, that are good indicators of the state of skin hydration. This paper reports near infrared spectrophotometric measurements using a highly sophisticated spectrophotometer in the region of 1000-2500 nm to study the water uptake and dehydration properties of skin in vitro using samples of porcine skin. Initial results of pure liquid water and skin samples have clearly displayed the prominent bands associated with water content, and desorption tests have been able to verify changes in these bands associated with water content, although a clear correlation between the rates of weight loss and absorbance loss at various hydration periods has not yet been established. These preliminary results are expected to further explain the relationship between water and skin, and its role within, in hope to aid the future development of a portable instrument based on near infrared spectroscopy that would be capable of directly measuring skin hydration and/or water content in a fast and noninvasive manner
Inhibitory Spillover: Increased Urination Urgency Facilitates Impulse Control in Unrelated Domains
Visceral states are known to reduce the ability to exert self-control. In the current research, we investigated how self-control
is affected by a visceral factor associated with inhibition rather than with approach: bladder control. We designed four studies
to test the hypothesis that inhibitory signals are not domain-specific but can spill over to unrelated domains, resulting in
increased impulse control in the behavioral domain. In Study 1, participants’ urination urgency correlated with performance on
color-naming but not word-meaning trials of a Stroop task. In Studies 2 and 3, we found that higher levels of bladder pressure
resulted in an increased ability to resist impulsive choices in monetary decision making. We found that inhibitory spillover
effects are moderated by sensitivity of the Behavioral Inhibition System (Study 3) and can be induced by exogenous cues
(Study 4). Implications for inhibition and impulse-control theories are discussed
Hyperelastic Ex Vivo Cervical Tissue Mechanical Characterization
This paper presents the results of the comparison between a proposed Fourth Order Elastic
Constants (FOECs) nonlinear model defined in the sense of Landau’s theory, and the two most
contrasted hyperelastic models in the literature, Mooney–Rivlin, and Ogden models. A mechanical
testing protocol is developed to investigate the large-strain response of ex vivo cervical tissue samples
in uniaxial tension in its two principal anatomical locations, the epithelial and connective layers.
The final aim of this work is to compare the reconstructed shear modulus of the epithelial and
connective layers of cervical tissue. According to the obtained results, the nonlinear parameter
A from the proposed FOEC model could be an important biomarker in cervical tissue diagnosis.
In addition, the calculated shear modulus depended on the anatomical location of the cervical tissue
(mepithelial = 1.29 0.15 MPa, and mconnective = 3.60 0.63 MPa) .Ministry of Education
DPI2017-83859-R
DPI2014-51870-R
UNGR15-CE-3664Ministry of Health - Turkey
DTS15/00093Junta de AndalucĂa
PI16/00339
PI-0107-2017
PIN-0030-201
P02.35. Methodology in integrative medicine research: challenges and solutions from a randomized clinical control trial using adapted yoga
Purpose
This randomized controlled clinical study evaluated the efficacy of adapted yoga (vs. usual care) to reduce psychosocial risks, which have been clinically shown to impact morbidity and mortality in implantable cardioverter defibrillator (ICD) recipients. The ICD collects and records real-time cardiac data, which were used in the study.
Methods
Forty-six patients participated from a hospital in Connecticut. All participants were administered validated measures on psychosocial risk factors at weeks one and eight of the eight-week intervention. Patients in the intervention group participated in a weekly adapted yoga class for eighty minutes for eight weeks with assigned home practices. Clinical measures, including patients’ current and past medical health status and device usage, were collected three months prior to the study, during the study, and at a six-month follow-up.
Results
Data revealed that the yoga group’s overall shock anxiety decreased while the control group’s increased, t(4.43, 36), p<0.0001 (total). The yoga group had less shock anxiety, t(2.86,36) p=0.007 (mean consequence), greater overall self-compassion, t(-2.84,37), p=0.007 (total), and greater mindfulness (equanimity) regarding emotions, t(-2.10,37) p=0.04 (mindfulness), than the control group. Exploratory analyses utilizing a linear model (R2=.98) of the observed anti-tachycardia pacing (ATP) events revealed that the expected number of ATP events in the intervention group was significantly lower than the control group. Additionally, the expected number of ATP events increased more rapidly as a function of the initial ATP events for the control group than for the intervention group.
Conclusion
Our study demonstrated psychological benefits from a program of adapted yoga compared to usual care for ICD recipients. Marked improvements were reported in total shock anxiety, self-compassion, sense of equanimity, and decreased likelihood of ATPs. The data supports the continuation of research in mind-body interventions to better understand the role of complementary medicine to address ICD-specific psychosocial stress and its potential contributory role in cardiac outcomes
Fatal Void Size Comparisons in Via-Below and Via-Above Cu Dual-Damascene Interconnects
The median-times-to-failure (t₅₀’s) for straight dual-damascene via-terminated copper interconnect structures, tested under the same conditions, depend on whether the vias connect down to underlaying leads (metal 2, M2, or via-below structures) or connect up to overlaying leads (metal 1, M1, or via-above structures). Experimental results for a variety of line lengths, widths, and numbers of vias show higher t₅₀’s for M2 structures than for analogous M1 structures. It has been shown that despite this asymmetry in lifetimes, the electromigration drift velocity is the same for these two types of structures, suggesting that fatal void volumes are different in these two cases. A numerical simulation tool based on the Korhonen model has been developed and used to simulate the conditions for void growth and correlate fatal void sizes with lifetimes. These simulations suggest that the average fatal void size for M2 structures is more than twice the size of that of M1 structures. This result supports an earlier suggestion that preferential nucleation at the Cu/Si₃N₄ interface in both M1 and M2 structures leads to different fatal void sizes, because larger voids are required to span the line thickness in M2 structures while smaller voids at the base of vias can cause failures in M1 structures. However, it is also found that the fatal void sizes corresponding to the shortest-times-to-failure (STTF’s) are similar for M1 and M2, suggesting that the voids that lead to the shortest lifetimes occur at or in the vias in both cases, where a void need only span the via to cause failure. Correlation of lifetimes and critical void volumes provides a useful tool for distinguishing failure mechanisms.Singapore-MIT Alliance (SMA
The design, hysteresis modeling and control of a novel SMA-fishing-line actuator
Fishing line can be combined with shape memory alloy (SMA) to form novel artificial muscle actuators which have low cost, are lightweight and soft. They can be applied in bionic, wearable and rehabilitation robots, and can reduce system weight and cost, increase power-to-weight ratio and offer safer physical human-robot interaction. However, these actuators possess several disadvantages, for example fishing line based actuators possess low strength and are complex to drive, and SMA possesses a low percentage contraction and has high hysteresis. This paper presents a novel artificial actuator (known as an SMA-fishing-line) made of fishing line and SMA twisted then coiled together, which can be driven directly by an electrical voltage. Its output force can reach 2.65N at 7.4V drive voltage, and the percentage contraction at 4V driven voltage with a 3N load is 7.53%. An antagonistic bionic joint driven by the novel SMA-fishing-line actuators is presented, and based on an extended unparallel Prandtl-Ishlinskii (EUPI) model, its hysteresis behavior is established, and the error ratio of the EUPI model is determined to be 6.3%. A Joule heat model of the SMA-fishing-line is also presented, and the maximum error of the established model is 0.510mm. Based on this accurate hysteresis model, a composite PID controller consisting of PID and an integral inverse (I-I) compensator is proposed and its performance is compared with a traditional PID controller through simulations and experimentation. These results show that the composite PID controller possesses higher control precision than basic PID, and is feasible for implementation in an SMA-fishing-line driven antagonistic bionic joint
Review of Modern Techniques for the Assessment of Skin Hydration
Skin hydration is a complex process that influences the physical and mechanical properties of skin. Various technologies have emerged over the years to assess this parameter, with the current standard being electrical probe-based instruments. Nevertheless, their inability to provide detailed information has prompted the use of sophisticated spectroscopic and imaging methodologies, which are capable of in-depth skin analysis that includes structural and composition details. Modern imaging and spectroscopic techniques have transformed skin research in the dermatological and cosmetics disciplines, and are now commonly employed in conjunction with traditional methods for comprehensive assessment of both healthy and pathological skin. This article reviews current techniques employed in measuring skin hydration, and gives an account on their principle of operation and applications in skin-related research
To sit or stand? A preliminary, cross sectional study to investigate if there is a difference in glenohumeral subluxation in sitting or standing in people following stroke
Background: Glenohumeral subluxation (GHS) is a common symptom following stroke. Many therapists postulate that GHS may be reduced if the base of support (BOS) is reduced and the centre of mass (COM) is raised as this requires greater postural muscle activity. However, there is little empirical evidence to support this practice.
Objective: The aim of this preliminary study was to investigate if the amount of GHS alters from sitting to standing.
Study design: A cross sectional, within-subject design in a convenience sample of 15 stroke patients with GHS was utilised.
Methods: A prospective design was used with a single blinded tester who assessed GHS using the calliper method in sitting, standing and on return to sitting. Friedman and post hoc Wilcoxon tests showed that GHS was significantly reduced in standing compared to sitting (p <0.05) but this reduction was not maintained on return to sitting (p = 0.25).
Conclusions: The results of this study are limited by its small size. However, these results indicate that reducing BOS during rehabilitation may improve GHS after stroke. Whilst the maintenance of benefit is not established, these findings suggest that reducing BOS as part of treatment may help patients with GHS. Further research is now required to replicate these results in a larger sample and to directly examine shoulder muscle activity to investigate which muscles may influence GHS in response to changing BOS. Future work could also aim to determine whether the reduction in GHS was directly attributable to a reduced BOS or the effort associated with moving from sitting to standing
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