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Brand S, Colledge F, Beeler N, et al. Neuropsychiatr Dis Treat. 2016;12:1309– 1317. Page 1309, Abstract, Methods, the text “All psychiatric hospitals (N=55) in the German-speaking part of Switzerland were contacted in spring 2014” should read “All psychiatric hospitals (N=55) in the German-speaking part of Switzerlandwere contacted in spring 2012”. The authors apologize for this error and advise it does not affect the results of the paper. Read the original article

The evolution of a fault's frictional strength during the interseismic period is a critical component of the earthquake cycle, yet there have been relatively few studies that examine the time‐dependent evolution of strength at conditions representative of seismogenic depths. Using a simulated fault in Westerly granite, we examined how frictional strength evolves under hydrothermal conditions up to 250°C during slide‐hold‐slide experiments. At temperatures ≤100°C, frictional strength generally increases with hold duration but, at 200 and 250°C, an initial increase in strength transitions to rapid time‐dependent weakening for holds longer than 14 hr. Forward modeling of long hold periods at 250°C using the rate and state friction constitutive equations requires a second, strongly negative, state variable with a long evolution distance. This implies that significant hydrothermal alteration is occurring at 250°C, consistent with microstructural observations of dissolution and secondary mineral precipitation. Plain Language Summary: A fault can regain strength following an earthquake. The rates, conditions, and mechanisms by which this recovery of strength occurs are not well understood but they are critical to understanding earthquake recurrence and induced seismicity. By conducting a series of experiments in which a simulated fault alternates between shear displacement and quasi‐stationary hold periods, we examine how fault strength evolves with time at temperatures up to 250°C. At elevated temperatures the fault initially strengthens but then weakens over long timescales. This weakening appears to be due to hydrothermal alteration, potentially including the precipitation of secondary minerals in the fault. Relating this observed weakening behavior and associated mechanisms to constitutive equations will facilitate modeling earthquake behavior in different materials and at variety of environmental conditions. Key Points: Time‐dependent weakening of simulated fault surfaces at hydrothermal conditions is observedWeakening mechanism is water‐assisted, temperature‐dependent, and depends on host rock compositionCapturing frictional behavior across all time scales requires a rate and state model with two state variables and a time delay parameter [ABSTRACT FROM AUTHOR]

Serge Brand,1,2 Flora Colledge,2 Nadja Beeler,2 Uwe Pühse,2 Nadeem Kalak,1 Dena Sadeghi Bahmani,1 Thorsten Mikoteit,1 Edith Holsboer-Trachsler,1 Markus Gerber2 1Psychiatric Clinics of the University of Basel, Center for Affective, Stress and Sleep Disorders, 2Department of Sport, Exercise and Health, Sport Science Section, University of Basel, Basel, Switzerland Background: Physical activity and exercise programs (PAEPs) are an important factor in increasing and maintaining physical and mental health. This holds particularly true for patients with psychiatric disorders undergoing treatment in a psychiatric hospital. To understand whether the benefits reported in the literature are mirrored in current treatment modalities, the aim of the present study was to assess the current state of PAEPs in psychiatric hospitals in the German-speaking part of Switzerland. Methods: All psychiatric hospitals (N=55) in the German-speaking part of Switzerland were contacted in spring 2014. Staff responsible for PAEPs were asked to complete an online questionnaire covering questions related to PAEPs such as type, frequency, staff training, treatment rationale, importance of PAEPs within the treatment strategy, and possible avenues to increase PAEPs. Results: Staff members of 48 different psychiatric hospitals completed the survey. Hospitals provided the following therapeutic treatments: relaxation techniques (100%), sports therapy (97%), activity-related psychotherapeutic interventions (95%), physiotherapy (85%), body therapies (59%), far-east techniques (57%), and hippotherapy (22%). Frequencies ranged from once/week to five times/week. Approximately 25% of patients participated in the PAEPs. Interventions were offered irrespective of psychiatric disorders. PAEP providers wanted and needed more vocational training. Conclusion: All participating psychiatric hospitals offer a broad variety of PAEPs in their treatment curricula. However, the majority of inpatients do not participate in PAEPs. Furthermore, those who do participate cannot continue to do so following discharge. PAEP providers need specific extended vocational trainings and believe that the potential of PA should be improved. Keywords: physical activity, psychiatric disorders, psychiatric hospitals, German-speaking part of Switzerland, sport participation

Defining roughness as the ratio of height to length, the standard approach to characterize amplitudes of single fault, joint and fracture surfaces is to measure average height as a function of profile length. Empirically, this roughness depends strongly on scale. The ratio is approximately 0.01 at a few mm but 10× smaller at a few tens of meters. Surfaces are rougher at small scales. However, these conclusions are metric‐dependent. If instead height is averaged over wavelength, roughness is nearly Brown spatial noise, having almost scale‐independent apparent surface height to wavelength ratio. The small deviation from scale‐independence is of the opposite sense than found using the standard metric; surfaces are slightly rougher at long wavelengths. Some natural surfaces may be Brownian within the measurement uncertainties. These contradictions are curiosities of surfaces that have Hurst exponents between 0.5 and 1, as natural fault surfaces do. The wavelength‐based analysis of roughness and how it changes with scale are straight‐forward; a normalized Fourier transform approximately preserves amplitude and its scale dependence in the wavelength domain. Among the conclusions from reconsideration of scale dependence are that the scale dependence is weak and much smaller than that of other fault and shear zone properties. Background and aftershock seismicity, jogs and step‐overs indicate strong localization (smoothing) with slip and scale. The lack of strong scale dependence to surface roughness suggests it is not the dominant control on brittle shear zone evolution. Plain Language Summary: "Surface roughness" is amplitude relative to length of a single surface. Surface roughness is thought to contribute significantly to shear strength. When defined as a ratio of average height to profile length, this roughness of exhumed surfaces is strongly scale dependent. It is approximately 0.01 at a few mm but more than 10× smaller at 10 m. If instead surface roughness is an amplitude to wavelength ratio, the conclusions are different. This ratio is nearly wavelength‐independent; exhumed natural surfaces are nearly Brown spatial noise and are slightly smoother at short wavelength. The apparent contradiction from these two different ratios is a curiosity of surface roughness between self‐similar (scale‐independent height to profile length) and Brownian (scale‐independent height to wavelength). Practically all natural surfaces are in this range. Analysis of surface roughness, its scaling and its extrapolation in scale are straight‐forward with the amplitude to wavelength ratio; a normalized Fourier transform approximately preserves scale dependence and the actual amplitudes and in the spectral domain. When compared with other fault and shear zone properties that indicate localization (smoothing) with slip and scale, the lack of scale dependence to surface roughness suggests it is not the dominant control on shear zone evolution. Key Points: Over the range of observed scales fault surface roughness (a ratio of surface height to length) is not well‐described by a purely fractal modelAmplitude/wavelength of exhumed surfaces is nearly Brown spatial noise, and can be easily extrapolated over large spatial scalesSurface roughness may not be the dominant control on changes in fault properties with scale or slip [ABSTRACT FROM AUTHOR]

During rock friction experiments at large displacement, room temperature and humidity, and following a hold test, the fracture energy increases approximately as the square of the logarithm of hold duration. While it's been long known that failure strength increases with log hold time, here the slip weakening distance, dh, also increases. The weakening distance increase is large, hundreds of percent change over a few thousand seconds. The initial bare surface and simulated fault gouge experiments were conducted in rotary shear at 25 MPa normal stress, 21 MPa confining stress and at displacements greater than 100 mm. In contrast, initially bare surface experiments at 5 MPa normal stress, unconfined at displacements less than 10 mm show effectively no change in dh. We attribute the difference to the presence of an appreciable shear zone that develops due to wear over significant displacements, confined at elevated normal stress. Prior published studies of sheared simulated fault gouge at short displacement show both acknowledged and unacknowledged increases in dh that may relate to our observations. Since natural faults have well‐developed shear zones, the observations have more direct relevance to earthquake nucleation than prior laboratory studies that use short displacement data and focus on frictional strength recovery alone. However, the physics underlying this increase in weakening distance are not known; candidates are compaction (Nakatani, 1998) and delocalization (Sleep et al., 2000). Additional caveats are that these are room temperature and humidity experiments, at a single normal stress that have not yet been reproduced in other laboratories. Plain Language Summary: The slip weakening distance in room temperature and humidity, confined, large displacement faulting experiments increases quasi‐linearly with the logarithm of time since the last slip event. The increase is absent in experiments that lack an appreciable shear zone and we attribute the observed effect to changes in fault properties within the wear or gouge material. The observations suggest 'toughening' of natural faults zone during the interseismic period, where the energy dissipated in initiating failure increases more dramatically with age than suggested in prior studies. Key Points: Fracture energy increases with the square of the logarithm of hold time in laboratory rock friction experimentsThe post peak weakening distance increases with the logarithm of hold timeThe weakening distance increase is large, hundreds of percent change over a few thousand seconds [ABSTRACT FROM AUTHOR]

Earthquake instability occurs as a result of strength loss during sliding on a fault. It has been known for over 50 years that fault compaction or dilatancy may cause significant weakening or strengthening by dramatically changing the fluid pressure trapped in faults. Despite this fundamental importance, we have no real understanding of the exact conditions that lead to compaction or dilation during nucleation or rupture. To date, no direct measurements of pore pressure changes during slip in hydraulically isolated faults have been reported. We show direct examples of fluid pressure variations during nucleation and rupture using a miniature pressure transducer embedded in an experimental fault. We demonstrate that fluids not only are significant in controlling fault behavior but can provide the dominant mechanism controlling fault stability. The effect of fluid pressure changes can exceed frictional variations predicted by rate‐ and state‐dependent friction laws, exerting fundamental controls on earthquake rupture initiation. Key Points: Direct measurements of pore pressure show variations during nucleation and rupture using a miniature pressure transducerFluids and intrinsic friction interact in controlling fault stabilityThe effect of fluid pressure changes can exceed frictional variations predicted by the rate‐ and state‐dependent friction laws [ABSTRACT FROM AUTHOR]

We compared near-fault velocity spectra recorded during laboratory experiments to that of natural earthquakes. We fractured crystalline rock samples at room temperature and intermediate confining pressure (50 MPa). Subsequent slip events were generated on the fracture surfaces under higher confinement (300 MPa). Velocity spectra from rock fracture resemble the inverse frequency (1/f) decay of natural earthquake velocity. This spectrum can be attributed to fault creation via seismic fracturing over a wide range of spatial scales. In contrast, subsequent slips on the rough fracture surfaces are depleted in high frequency energy and falloff approximately as 1/f². The 1/f² spectrum is more consistent with a slider-block model obeying static-kinetic friction than a natural earthquake. The depleted high frequency content precludes the rough fault experiments from being directly analogous to natural sources. The suppression of high frequencies may have resulted from two possible factors: (1) the presence of a well-developed shear zone and coseismic damping of the fault motion by dissipation within it or, in our favored interpretation, (2) a smaller amount of energy dissipated by shearing relative to the total energy release at elevated confining pressure. In context of the latter explanation, a unifying concept that applies to these experiments, earthquakes, ground motion, and models of complex radiated motion is that high frequency radiated energy is relatively enhanced when total energy release is nearly balanced within the source region by dissipative processes. This near-critical energy release condition can be accessed at low normal stress in laboratory experiments. [ABSTRACT FROM AUTHOR]

We investigate the implications of deformation experiments for the coseismic down-dip extent of rupture in quasi-dynamic, whole-cycle earthquake models of a fault for which the depth of the transition between seismic and aseisimic fault slip depends on strain rate. The calculations use a dislocation fault model from Tse and Rice (1986) with a vertical strike-slip orientation, mode III rupture, and variable along-strike length. Our reference calculation is the original rheological representation of Tse and Rice with a strain-rate-independent transition. The primary calculations use two different representations of a strain-rate-dependent transition: (1) between rate-weakening friction and dislocation creep and (2) between rate-weakening and rate-strengthening frictions. For both these cases, when fault strength is high (friction between 0.5 and 0.6) and the transition is sharp, coseismic slip extends a small distance (1-2 km) below the fixed temperature (depth) that is commonly used to define the rheological transition at the plate-motion rate. Thus, coseismic slip occurs below the depth assumed in seismic hazard models using microseismicity or a chosen fixed-temperature contour. Though significant coseismic slip occurs below the plate-rate transition depth, the added moment is <10% of the total. The deep extension is a region that is rheologically distinct; for example, deep coseismic slip can produce a stress increase rather than a stress drop. If friction is smaller, the deepening effect and its contribution to moment are larger. For all representations of the transition, average and surface slip increase with the along-strike rupture length in a manner consistent with the limited data from natural observations. However, this property is not controlled by the assumed fault rheology; instead, it arises because the stiffness of the fault decreases weakly with fault length, an intrinsic and unrealistic property of the particular crustal scale fault model used. [ABSTRACT FROM AUTHOR]

Abstract: Families of recurring low‐frequency earthquakes (LFEs) within nonvolcanic tremor on the San Andreas Fault in central California are sensitive to tidal stresses. LFEs occur at all levels of the tides, are strongly correlated and in phase with the ~200 Pa shear stresses, and weakly and not systematically correlated with the ~2 kPa tidal normal stresses. We assume that LFEs are small sources that repeatedly fail during shear within a much larger scale, aseismically slipping fault zone and consider two different models of the fault slip: (1) modulation of the fault slip rate by the tidal stresses or (2) episodic slip, triggered by the tides. LFEs are strongly clustered with duration much shorter than the semidiurnal tide; they cannot be significantly modulated on that time scale. The recurrence times of clusters, however, are many times longer than the semidiurnal, leading to an appearance of tidal triggering. In this context we examine the predictions of laboratory‐observed triggered frictional (dilatant) fault slip. The undrained end‐member model produces no sensitivity to the tidal normal stress, and slip onsets are in phase with the tidal shear stress. The tidal correlation constrains the diffusivity to be less than ~1 × 10−6/s and the product of the friction and dilatancy coefficients to be at most 5 × 10−7, orders of magnitude smaller than observed at room temperature. In the absence of dilatancy the effective normal stress at failure would be about ~55 kPa. For this model the observations require intrinsic weakness, low dilatancy, and lithostatic pore fluid. [ABSTRACT FROM AUTHOR]

Abstract: The central section of the San Andreas Fault hosts tectonic tremor and low‐frequency earthquakes (LFEs) similar to subduction zone environments. LFEs are often interpreted as persistent regions that repeatedly fail during the aseismic shear of the surrounding fault allowing them to be used as creepmeters. We test this idea by using the recurrence intervals of individual LFEs within LFE families to estimate the timing, duration, recurrence interval, slip, and slip rate associated with inferred slow slip events. We formalize the definition of a creepmeter and determine whether this definition is consistent with our observations. We find that episodic families reflect surrounding creep over the interevent time, while the continuous families and the short time scale bursts that occur as part of the episodic families do not. However, when these families are evaluated on time scales longer than the interevent time these events can also be used to meter slip. A straightforward interpretation of episodic families is that they define sections of the fault where slip is distinctly episodic in well‐defined slow slip events that slip 16 times the long‐term rate. In contrast, the frequent short‐term bursts of the continuous and short time scale episodic families likely do not represent individual creep events but rather are persistent asperities that are driven to failure by quasi‐continuous creep on the surrounding fault. Finally, we find that the moment‐duration scaling of our inferred creep events are inconsistent with the proposed linear moment‐duration scaling. However, caution must be exercised when attempting to determine scaling with incomplete knowledge of scale. [ABSTRACT FROM AUTHOR]

Coseismic frictional melting and the production of quenched glass called pseudotachylyte is a recurring process during earthquakes. To investigate how glassy materials affect the postseismic strength and stability of faults, obsidian gouges were sheared under dry and wet conditions from 200°C to 300°C at ~150 MPa effective normal stress. Dry glass exhibited a brittle rheology at all conditions tested, exhibiting friction values and microstructures consistent with siliciclastic materials. Likewise, wet glass at 200°C exhibited a brittle rheology. In contrast, wet gouges at 300°C transitioned from brittle sliding to linear-viscous (Newtonian) flow at strain rates <3 × 10−4 s−1, indicating melt-like behavior. The viscosity ranged from 2 × 1011 to 7.8 × 1011 Pa-s. Microstructures show that viscous gouges were fully welded with rod-shaped microlites rotated into the flow direction. Fourier transform infrared spectroscopy along with electron backscatter imaging demonstrate that hydration of the glass by diffusion of pore water was the dominant process reducing the viscosity and promoting viscous flow. As much as 5 wt % water diffused into the glass. These results may provide insight into postseismic-slip behaviors and challenge some interpretations of fault kinematics based on studies assuming that pseudotachylyte formation and flow is solely coseismic. [ABSTRACT FROM AUTHOR]

This study is to determine the detailed response of shear strength and other fault properties to changes in normal stress at room temperature using dry initially bare rock surfaces of granite at normal stresses between 5 and 7 MPa. Rapid normal stress changes result in gradual, approximately exponential changes in shear resistance with fault slip. The characteristic length of the exponential change is similar for both increases and decreases in normal stress. In contrast, changes in fault normal displacement and the amplitude of small high-frequency elastic waves transmitted across the surface follow a two stage response consisting of a large immediate and a smaller gradual response with slip. The characteristic slip distance of the small gradual response is significantly smaller than that of shear resistance. The stability of sliding in response to large step decreases in normal stress is well predicted using the shear resistance slip length observed in step increases. Analysis of the shear resistance and slip-time histories suggest nearly immediate changes in strength occur in response to rapid changes in normal stress; these are manifested as an immediate change in slip speed. These changes in slip speed can be qualitatively accounted for using a rate-independent strength model. Collectively, the observations and model show that acceleration or deceleration in response to normal stress change depends on the size of the change, the frictional characteristics of the fault surface, and the elastic properties of the loading system. [ABSTRACT FROM AUTHOR]

Earthquake-radiated motions contain information that can be interpreted as source displacement and therefore related to stress drop. Except in a few notable cases, these displacements cannot be easily related to the absolute stress level or the fault strength, or attributed to a particular physical mechanism. In contrast, paleoearthquakes recorded by exhumed pseudotachylite have a known dynamic mechanism whose properties constrain the coseismic fault strength. Pseudotachylite can be used to directly address a discrepancy between seismologically measured stress drops, which are typically a few MPa, and much larger dynamic stress drops expected from thermal weakening during slip at seismic speeds in crystalline rock (Mckenzie and Brune, 1972; Sibson, 1973; Lachenbruch, 1980; Mase and Smith, 1987; Rice, 2006), and as have been observed in laboratory experiments at high slip rates (Di Toro, Hirose, Nielsen, Pennacchioni, et al., 2006). This places pseudotachylite-derived estimates of fault strength and inferred crustal stress within the context and bounds of naturally observed earthquake source parameters: apparent stress, stress drop, and overshoot, including consideration of fault-surface roughness, off-fault damage, fracture energy, and the strength excess. The analysis, which assumes stress drop is related to corner frequency as in the Madariaga (1976) source model, is restricted to earthquakes of the Gole Larghe fault zone in the Italian Alps, where the dynamic shear strength is well constrained by field and laboratory measurements. We find that radiated energy is similar to or exceeds the shear-generated heat and that the maximum strength excess is ~16 MPa. These events have inferred earthquake source parameters that are rare, for instance, a low percentage of the global earthquake population has stress drops as large, unless fracture energy is routinely greater than in existing models, pseudotachylite is not representative of the shear strength during the earthquake that generated it, or the strength excess is larger than we have allowed. [ABSTRACT FROM AUTHOR]

To characterize stress and deformation style at the base of the seismogenic zone, we investigate how the mechanical properties of fluid-rock systems respond to variations in temperature and strain rate. The role of fluids on the processes responsible for the brittle-ductile transition in quartz-rich rocks has not been explored at experimental conditions where the kinetic competition between microcracking and viscous flow is similar to that expected in the Earth. Our initial analysis of this competition suggests that the effective stress law for sliding friction should not work as efficiently near the brittleductile transition as it does at shallow conditions. [ABSTRACT FROM AUTHOR]

To account for natural spatial and temporal complexity, large-scale, long-duration calculations are required for simulations of seismicity in fault zones that host large earthquakes. Without advances in computational methods, the rate of progress in "earthquake simulator" models and associated earthquake forecasts is limited by the rates at which computer speed and storage increase. To explore improvements in computational efficiency we develop the first implementation of the Barnes-Hut algorithm (Barnes and Hut, 1986) to calculate elastic interactions in a fault model. The Barnes-Hut method is an efficient, numerical scheme that treats local forces exactly and "distant forces approximately. The approach is illustrated in example simulations of non-linear fault strength in plane strain. Rudimentary error analysis indicates that efficient calculations, where execution time scales with number of grid points (N) as N log N, can be conducted routinely with errors on the order of 0.1%. We expect the Barnes-Hut method to be well suited for conducting initial exploration of parameter space for fault simulations with non-linear constitutive equations, and for efficient calculations of stress interaction in complex fault systems. [ABSTRACT FROM AUTHOR]

Laboratory stick-slip friction experiments indicate that peak slip rates increase with the stresses loading the fault to cause rupture. If this applies also to earthquake fault zones, then the analysis of rupture processes is simplified inasmuch as the slip rates depend only on the local yield stress and are independent of factors specific to a particular event, including the distribution of slip in space and time. We test this hypothesis by first using it to develop an expression for radiated energy that depends primarily on the seismic moment and the maximum slip rate. From laboratory results, the maximum slip rate for any crustal earthquake, as well as various stress parameters including the yield stress, can be determined based on its seismic moment and the maximum slip within its rupture zone. After finding that our new equation for radiated energy works well for laboratory stick-slip friction experiments, we used it to estimate radiated energies for five earthquakes with magnitudes near 2 that were induced in a deep gold mine, an M 2.1 repeating earthquake near the San Andreas Fault Observatory at Depth (SAFOD) site and seven major earthquakes in California and found good agreement with energies estimated independently from spectra of local and regional ground-motion data. Estimates of yield stress for the earthquakes in our study range from 12 MPa to 122 MPa with a median of 64 MPa. The lowest value was estimated for the 2004 M 6 Parkfield, California, earthquake whereas the nearby M 2.1 repeating earthquake, as recorded in the SAFOD pilot hole, showed a more typical yield stress of 64 MPa. [ABSTRACT FROM AUTHOR]

Even though past research suggests that visual learning may benefit from conceptual knowledge, current interventions for medical image evaluation often focus on procedural knowledge, mainly by teaching classification algorithms. We compared the efficacy of pure procedural knowledge (three-point checklist for evaluating skin lesions) versus combined procedural plus conceptual knowledge (histological explanations for each of the three points). All students then trained their classification skills with a visual learning resource that included images of two types of pigmented skin lesions: benign nevi and malignant melanomas. Both treatments produced significant and long-lasting effects on diagnostic accuracy in transfer tasks. However, only students in the combined procedural plus conceptual knowledge condition significantly improved their diagnostic performance in classifying lesions they had seen before in the pre- and post-tests. Findings suggest that the provision of additional conceptual knowledge supported error correction mechanisms., (© 2023. The Author(s).)

It is important but challenging for prospective health professionals to learn the visual distinction between potentially harmful and harmless skin lesions, such as malignant melanomas and benign nevi. Knowledge about factors related to diagnostic performance is sparse but a prerequisite for designing and evaluating evidence-based educational interventions. Hence, this study explored how the characteristics of 240 skin lesions, the number of classified lesions and the response times of 137 laypeople were related to performance in diagnosing pigmented skin cancer. Our results showed large differences between the lesions, as some were classified correctly by more than 90% and others by less than 10% of the participants. A t-test showed that for melanomas, the correct diagnosis was provided significantly more often than for nevi. Furthermore, we found a significant Pearson correlation between the number of solved tasks and performance in the first 50 diagnostic tasks. Finally, t-tests for investigating the response times revealed that compared to true decisions, participants spent longer on false-negative but not on false-positive decisions. These results provide novel knowledge about performance-related factors that can be useful when designing diagnostic tests and learning interventions for melanoma detection., (© 2023. The Author(s).)

Objectives. To investigate the validity of different devices and algorithms used in military organizations worldwide to assess physical activity energy expenditure (PAEE) and heart rate (HR) among soldiers. Design. Device validation study. Methods . Twenty-three male participants serving their mandatory military service accomplished, firstly, nine different military specific activities indoors, and secondly, a normal military routine outdoors. Participants wore simultaneously an ActiHeart, Everion, MetaMax 3B, Garmin Fenix 3, Hidalgo EQ02, and PADIS 2.0 system. The PAEE and HR data of each system were compared to the criterion measures MetaMax 3B and Hidalgo EQ02, respectively. Results . Overall, the recorded systematic errors in PAEE estimation ranged from 0.1 (±1.8) kcal.min -1 to -1.7 (±1.8) kcal.min -1 for the systems PADIS 2.0 and Hidalgo EQ02 running the Royal Dutch Army algorithm, respectively, and in the HR assessment ranged from -0.1 (±2.1) b.min -1 to 0.8 (±3.0) b.min -1 for the PADIS 2.0 and ActiHeart systems, respectively. The mean absolute percentage error (MAPE) in PAEE estimation ranged from 29.9% to 75.1%, with only the Everion system showing an overall MAPE <30%, but all investigated devices reported overall MAPE <1.4% in the HR assessment. Conclusions . The present study demonstrated poor to moderate validity in terms of PAEE estimation, but excellent validity in all investigated devices in terms of HR assessment. Overall, the Everion performed among the best in both parameters and with a device placement on the upper arm, the Everion system is particularly useful during military service, as it does not interfere with other relevant equipment., (Creative Commons Attribution license.)

Unveiling the key pathways underlying postnatal beta-cell proliferation can be instrumental to decipher the mechanisms of beta-cell mass plasticity to increased physiological demand of insulin during weight gain and pregnancy. Using transcriptome and global Serine Threonine Kinase activity (STK) analyses of islets from newborn (10 days old) and adult rats, we found that highly proliferative neonatal rat islet cells display a substantially elevated activity of the mitogen activated protein 3 kinase 12, also called dual leucine zipper-bearing kinase (Dlk). As a key upstream component of the c-Jun amino terminal kinase (Jnk) pathway, Dlk overexpression was associated with increased Jnk3 activity and was mainly localized in the beta-cell cytoplasm. We provide the evidence that Dlk associates with and activates Jnk3, and that this cascade stimulates the expression of Ccnd1 and Ccnd2, two essential cyclins controlling postnatal beta-cell replication. Silencing of Dlk or of Jnk3 in neonatal islet cells dramatically hampered primary beta-cell replication and the expression of the two cyclins. Moreover, the expression of Dlk, Jnk3, Ccnd1 and Ccnd2 was induced in high replicative islet beta cells from ob/ob mice during weight gain, and from pregnant female rats. In human islets from non-diabetic obese individuals, DLK expression was also cytoplasmic and the rise of the mRNA level was associated with an increase of JNK3, CCND1 and CCND2 mRNA levels, when compared to islets from lean and obese patients with diabetes. In conclusion, we find that activation of Jnk3 signalling by Dlk could be a key mechanism for adapting islet beta-cell mass during postnatal development and weight gain.

This study aimed to evaluate the accuracy of three measurement systems estimating gait speed during a loaded military march over graded terrain. Systems developed by the Swiss and Netherlands Armed Forces and a commercial wrist-based device were evaluated in comparison to a Global Positioning System. The first part of the paper focuses on the development of the Dutch system, where speed is estimated from a chest worn accelerometer and body measurements. For this validation study 36 subjects were walking or running 13 laps of 200 m at different speeds. Results showed that walking and running speed can be estimated with a R 2 adj of 0.968 and 0.740, respectively. In the second part of this paper, data from 64 soldiers performing a 35 km march were used to evaluate the accuracy of three measurement systems in estimating speed. Data showed that estimating gait speed with a single accelerometer can be accurate for military activity, even without prior individual calibration measurements. However, predictions should be corrected for confounders such as body size and shoe type to be accurate. Both, downhill and uphill walking led to changes in gait characteristics and to an overestimation of speed by up to 10%. Correcting for slope or gradient using altimetry in future algorithms/experiments could improve the estimation of gait speed., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: The aim of this study was to assess the accuracy of three different sport watches in estimating energy expenditure during aerobic and anaerobic running., Methods: Twenty trained subjects ran at different intensities while wearing three commercial sport watches (Suunto Ambit2, Garmin Forerunner920XT, and Polar V800). Indirect calorimetry was used as the criterion measure for assessing energy expenditure. Different formulas were applied to compute energy expenditure from the gas exchange values for aerobic and anaerobic running., Results: The accuracy of the energy expenditure estimations was intensity-dependent for all tested watches. During aerobic running (4-11 km/h), mean absolute percentage error values of -25.16% to +38.09% were observed, with the Polar V800 performing most accurately (stage 1: -12.20%, stage 2: -3.61%, and stage 3: -4.29%). The Garmin Forerunner920XT significantly underestimated energy expenditure during the slowest stage (stage 1: -25.16%), whereas, the Suunto Ambit2 significantly overestimated energy expenditure during the two slowest stages (stage 1: 38.09%, stage 2: 36.29%). During anaerobic running (14-17 km/h), all three watches significantly underestimated energy expenditure by -21.62% to -49.30%. Therefore, the error in estimating energy expenditure systematically increased as the anaerobic running speed increased., Conclusions: To estimate energy expenditure during aerobic running, the Polar V800 is recommended. By contrast, the other two watches either significantly overestimated or underestimated energy expenditure during most running intensities. The energy expenditure estimations generated during anaerobic exercises revealed large measurement errors in all tested sport watches. Therefore, the algorithms for estimating energy expenditure during intense activities must be improved before they can be used to monitor energy expenditure during high-intensity physical activities., Competing Interests: The participants were informed about the procedure and aims of the study and signed a written informed consent form that had been previously approved by the Institutional Review Board. Ethical approval was obtained from the Institutional Review Board of the Swiss Federal Institute of Sport Magglingen.Not applicable.The authors declare that they have no competing interests.Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Background: Physical activity and exercise programs (PAEPs) are an important factor in increasing and maintaining physical and mental health. This holds particularly true for patients with psychiatric disorders undergoing treatment in a psychiatric hospital. To understand whether the benefits reported in the literature are mirrored in current treatment modalities, the aim of the present study was to assess the current state of PAEPs in psychiatric hospitals in the German-speaking part of Switzerland., Methods: All psychiatric hospitals (N=55) in the German-speaking part of Switzerland were contacted in spring 2014. Staff responsible for PAEPs were asked to complete an online questionnaire covering questions related to PAEPs such as type, frequency, staff training, treatment rationale, importance of PAEPs within the treatment strategy, and possible avenues to increase PAEPs., Results: Staff members of 48 different psychiatric hospitals completed the survey. Hospitals provided the following therapeutic treatments: relaxation techniques (100%), sports therapy (97%), activity-related psychotherapeutic interventions (95%), physiotherapy (85%), body therapies (59%), far-east techniques (57%), and hippotherapy (22%). Frequencies ranged from once/week to five times/week. Approximately 25% of patients participated in the PAEPs. Interventions were offered irrespective of psychiatric disorders. PAEP providers wanted and needed more vocational training., Conclusion: All participating psychiatric hospitals offer a broad variety of PAEPs in their treatment curricula. However, the majority of inpatients do not participate in PAEPs. Furthermore, those who do participate cannot continue to do so following discharge. PAEP providers need specific extended vocational trainings and believe that the potential of PA should be improved.

Background: A growing collection of retrospective studies have suggested that TP53 mutations and/or CDKN2A deletions have prognostic significance in Ewing sarcoma. We sought to evaluate these variables in patients with localized disease treated prospectively on a single Children's Oncology Group protocol., Procedure: Of the 568 patients enrolled on Children's Oncology Group protocol AEWS0031 (NCT00006734), 112 had tumor specimens of sufficient quality and quantity to allow for analysis of TP53 mutations status by DNA sequencing, and CDKN2A deletion by dual color fluorescent in situ hybridization., Results: Eight of 93 cases (8.6%) were found to have TP53 point mutations and 12 of 107 cases (11.2%) demonstrated homozygous CDKN2A deletion. Two cases were found to have an alteration in both genes. There was no significant difference in event-free survival of patients with TP53 mutations and/or CDKN2A deletions compared to patients with normal TP53/CDKN2A gene status, as demonstrated by log rank test (p = 0.58)., Conclusions: Although previous retrospective studies suggest their significance, TP53 mutation and/or CDKN2A deletion are not reliable prognostic biomarkers in localized Ewing sarcoma., (© 2014 Wiley Periodicals, Inc.)