Continuous powering of wearable electronics and personalized biomonitoring systems remains a great challenge. One promising solution is the use of thermoelectric generators (TEGs) that convert body ...heat to electricity. These energy harvesters must conform to curved surfaces and minimize thermal barriers to maintain efficiency while still exhibiting durability under large deformations. Here, highly efficient, stretchable thermoelectric generators made of inorganic semiconductors and printed multifunctional soft matter are introduced. Liquid metal elastomer composites with tailored microstructures are printed as highly conductive thermal interface materials and stretchable interconnects. Additionally, elastomer composites with hollow microspheres are formulated to print a deformable and lightweight thermal insulator within the device. These stretchable thermoelectric wearables show an excellent performance by generating an open‐circuit voltage of 392 mV and a power density of ≈650 µW cm−2 at ∆T = 60 °C and withstanding more than 15 000 stretching cycles at 30% strain. Furthermore, the additive manufacturing process is leveraged by direct writing of the TEGs on textiles to demonstrate their seamless integration and by 3D printing of stretchable heatsinks to maintain a large temperature gradient across the device and to study the effect of convective heat transfer on device performance.
Eutectic gallium‐indium particles and hollow thermoplastic microspheres are mixed into elastomers to create functional inks for printing stretchable thermoelectric devices. This fabrication method results in durable thermoelectric generators with high power density while enabling device customization, 3D printing of stretchable heatsinks, and seamless integration of thermoelectrics into textiles for wearable applications.
Abstract
Additive manufacturing permits innovative soft device architectures with micron resolution. The processing requirements, however, restrict the available materials, and joining chemically ...dissimilar components remains a challenge. Here we report silicone double networks (SilDNs) that participate in orthogonal crosslinking mechanisms—photocurable thiol-ene reactions and condensation reactions—to exercise independent control over both the shape forming process (3D printing) and final mechanical properties. SilDNs simultaneously possess low elastic modulus (
E
100%
< 700kPa) as well as large ultimate strains (d
L/L
0
up to ~ 400 %), toughnesses (
U
~ 1.4 MJ·m
−3
), and strengths (
σ
~ 1 MPa). Importantly, the latent condensation reaction permits cohesive bonding of printed objects to dissimilar substrates with modulus gradients that span more than seven orders of magnitude. We demonstrate soft devices relevant to a broad range of disciplines: models that simulate the geometries and mechanical properties of soft tissue systems and multimaterial assemblies for next generation wearable devices and robotics.
The maximal rate of rise in muscle force rate of force development (RFD) has important functional consequences as it determines the force that can be generated in the early phase of muscle ...contraction (0-200 ms). The present study examined the effect of resistance training on contractile RFD and efferent motor outflow ("neural drive") during maximal muscle contraction. Contractile RFD (slope of force-time curve), impulse (time-integrated force), electromyography (EMG) signal amplitude (mean average voltage), and rate of EMG rise (slope of EMG-time curve) were determined (1-kHz sampling rate) during maximal isometric muscle contraction (quadriceps femoris) in 15 male subjects before and after 14 wk of heavy-resistance strength training (38 sessions). Maximal isometric muscle strength maximal voluntary contraction (MVC) increased from 291.1 +/- 9.8 to 339.0 +/- 10.2 N. m after training. Contractile RFD determined within time intervals of 30, 50, 100, and 200 ms relative to onset of contraction increased from 1,601 +/- 117 to 2,020 +/- 119 (P < 0.05), 1,802 +/- 121 to 2,201 +/- 106 (P < 0.01), 1,543 +/- 83 to 1,806 +/- 69 (P < 0.01), and 1,141 +/- 45 to 1,363 +/- 44 N. m. s(-1) (P < 0.01), respectively. Corresponding increases were observed in contractile impulse (P < 0.01-0.05). When normalized relative to MVC, contractile RFD increased 15% after training (at zero to one-sixth MVC; P < 0.05). Furthermore, muscle EMG increased (P < 0.01-0.05) 22-143% (mean average voltage) and 41-106% (rate of EMG rise) in the early contraction phase (0-200 ms). In conclusion, increases in explosive muscle strength (contractile RFD and impulse) were observed after heavy-resistance strength training. These findings could be explained by an enhanced neural drive, as evidenced by marked increases in EMG signal amplitude and rate of EMG rise in the early phase of muscle contraction.
The forward lunge (FL) may be a promising movement to assess functional outcome after ACL reconstruction. Thus, we aimed to investigate the FL movement pattern before and after ACL reconstruction ...with a comparison to healthy controls to determine if differences were present. Twenty-eight ACL injured participants and 28 matched healthy controls were included. They performed FL movements while sagittal plane biomechanics of the knee and electromyography (EMG) of nine leg muscles was assessed. The ACL injured group was tested before and 10 months after surgery. The perceived knee function and activity level was assessed by questionnaires. The ACL injured group performed the FL significantly slower than the controls before surgery (mean difference: 0.41 s 95%CI: 0.04-0.79 s; p<0.05) while they performed the FL as fast as the controls after surgery (~28% movement time reduction post-surgery). Perceived knee function and activity level improved significantly post-surgery. The knee joint flexion angle, extensor moment, power, angular velocity in the ACL injured group did not differ from pre to post-surgery. For the ACL injured group, the peak knee extensor moment observed both pre and post-surgery was significantly lower when compared to the controls. The EMG results showed minimal differences. In conclusion, at 10 months post-surgery, the FL was performed significantly faster and the movement time was comparable to that of the controls. While the perceived knee function and activity level improved post-surgery, the knee joint biomechanics were unchanged. This may reflect that knee joint function was not fully restored.
Purpose
To determine the impact of socioeconomic position (SEP) and distance to provider on outpatient mental health care utilization among incident users of antidepressants.
Method
A nationwide ...register-based cohort study of 50,374 person-years.
Results
Persons in low SEP were more likely to have outpatient psychiatrist contacts odds ratio (OR) 1.25; confidence interval (CI) 1.17–1.34, but less likely to consult a co-payed psychologist (OR 0.49; CI 0.46–0.53) and to get mental health service from a GP (MHS-GP) (OR 0.81; CI 0.77–0.86) compared to persons in high SEP after adjusting for socio-demographics, comorbidity and car ownership. Furthermore, persons in low SEP who had contact to any of these therapists tended to have lower rates of visits compared to those in high SEP. When distance to services increased by 5 km, the rate of visits to outpatient psychiatrist tended to decrease by 5% in the lowest income group (IRR 0.95; CI 0.94–0.95) and 1% in the highest (IRR 0.99; CI 0.99–1.00). Likewise, contact to psychologists decreased by 11% in the lowest income group (IRR 0.89; CI 0.85–0.94), whereas rate of visits did not interact.
Conclusion
Patients in low SEP have relatively lower utilization of mental health services even when services are free at delivery; co-payment and distance to provider aggravate the disparities in utilization between patients in high SEP and patients in low SEP.
To review the effectiveness of psychological therapies for adolescents with borderline personality disorder (BPD) or BPD features.
We included randomized clinical trials on psychological therapies ...for adolescents with BPD and BPD features. Data were extracted and assessed for quality according to Cochrane guidelines, and summarized as mean difference (MD) with 95% confidence intervals (CI) for continuous data and as Odds ratios (OR) with 95% CI for dichotomous data. Risk of bias was assessed using Cochrane's risk of bias tool for each domain. When possible, we pooled trials into meta-analyses, and used Trial Sequential Analysis (TSA) to control for random errors. Quality of the evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE).
10 trials on adolescents with BPD or BPD features were included. All trials were considered at high risk of bias, and the quality of the evidence was rated as "very low". We did TSA on the primary outcome and found that the required information size was reached. The risk of random error was thus discarded.
Only 10 trials have been conducted on adolescents with BPD or BPD features. Of these only few showed superior outcomes of the experimental intervention compared to the control intervention. No adverse effects of the interventions were mentioned. Attrition rates varied from 15-75% in experimental interventions. The overall quality was very low due to high risk of bias, imprecision and inconsistency, which limits the confidence in effect estimates. Due to the high risk of bias, high attrition rates and underpowered studies in this area, it is difficult to derive any conclusions on the efficacy of psychological therapies for BPD in adolescence. There is a need for more high quality trials with larger samples to identify effective psychological therapies for this specific age group with BPD or BPD features.
Abstract The objective of this work is to present a musculo-skeletal model of the lumbar spine, which can be shared and lends itself to investigation in many locations by different researchers. This ...has the potential for greater reproducibility and subsequent improvement of its quality from the combined effort of different research groups. The model is defined in a text-based, declarative, object-oriented language in the AnyBody Modelling System software. Text-based models will facilitate sharing of the models between different research groups. The necessary data for the model has been taken from the literature. The work resulted in a detailed lumbar spine model with seven rigid segments with 18 degrees-of-freedom and 154 muscles. The model is able to produce a maximum extension moment of 238 Nm around L5/S1. Moreover, a comparison was made with in vivo intradiscal pressure measurements of the L4–5 disc available from the literature. The model is based on inverse dynamics, where the redundancy problem is solved using optimization in order to compute the individual muscle forces and joint reactions. With the presented model it is possible to investigate a range of research questions, because the model is relatively easy to share and modify due to the use of a well-defined and self-contained scripting language. Validation is though still necessary for specific cases.
In patients with sick sinus syndrome, bradycardia can be treated with a single-lead pacemaker or a dual-chamber pacemaker. Previous trials have revealed that pacing modes preserving atrio-ventricular ...synchrony are superior to single-lead ventricular pacing, but it remains unclear if there is any difference between single-lead atrial pacing (AAIR) and dual-chamber pacing (DDDR).
We randomly assigned 1415 patients referred for first pacemaker implantation to AAIR (n = 707) or DDDR (n = 708) pacing and followed them for a mean of 5.4 ± 2.6 years. The primary outcome was death from any cause. Secondary outcomes included paroxysmal and chronic atrial fibrillation, stroke, heart failure, and need for pacemaker reoperation. In the AAIR group, 209 patients (29.6%) died during follow-up vs. 193 patients (27.3%) in the DDDR group, hazard ratio (HR) 1.06, 95% confidence interval (CI) 0.88-1.29, P = 0.53. Paroxysmal atrial fibrillation was observed in 201 patients (28.4%) in the AAIR group vs. 163 patients (23.0%) in the DDDR group, HR 1.27, 95% CI 1.03-1.56, P = 0.024. A total of 240 patients underwent one or more pacemaker reoperations during follow-up, 156 (22.1%) in the AAIR group vs. 84 (11.9%) in the DDDR group (HR 1.99, 95% CI 1.53-2.59, P < 0.001). The incidence of chronic atrial fibrillation, stroke, and heart failure did not differ between treatment groups.
In patients with sick sinus syndrome, there is no statistically significant difference in death from any cause between AAIR pacing and DDDR pacing. AAIR pacing is associated with a higher incidence of paroxysmal atrial fibrillation and a two-fold increased risk of pacemaker reoperation. These findings support the routine use of DDDR pacing in these patients.
URL http://www.clinicaltrials.gov. Unique identifier: NCT00236158.
Early detection in first-episode psychosis confers advantages for negative, cognitive, and depressive symptoms after 1, 2, and 5 years, but longitudinal effects are unknown. The authors investigated ...the differences in symptoms and recovery after 10 years between regional health care sectors with and without a comprehensive program for the early detection of psychosis.
The authors evaluated 281 patients (early detection, N=141) 18 to 65 years old with a first episode of nonaffective psychosis between 1997 and 2001. Of these, 101 patients in the early-detection area and 73 patients in the usual-detection area were followed up at 10 years, and the authors compared their symptoms and recovery.
A significantly higher percentage of early-detection patients had recovered at the 10-year follow-up relative to usual-detection patients. This held true despite more severely ill patients dropping out of the study in the usual-detection area. Except for higher levels of excitative symptoms in the early-detection area, there were no symptom differences between the groups. Early-detection recovery rates were higher largely because of higher employment rates for patients in this group.
Early detection of first-episode psychosis appears to increase the chances of milder deficits and superior functioning. The mechanisms by which this strategy improves the long-term prognosis of psychosis remain speculative. Nevertheless, our findings over 10 years may indicate that a prognostic link exists between the timing of intervention and outcome that deserves additional study.
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