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Current regulatory tools are not well suited to address freshwater salinization in urban areas and the conditions under which bottom-up management is likely to emerge remain unclear. We hypothesize that Ostrom’s social-ecological-systems (SES) framework can be used to explore how current understanding of salinization might foster or impede its collective management. Our study focuses on the Occoquan Reservoir, a critical urban water supply in Northern Virginia, U.S., and uses fuzzy cognitive maps (FCMs) to characterize stakeholder understanding of the SES that underpins salinization in the region. Hierarchical clustering of FCMs reveals four stakeholder groups with distinct views on the causes and consequences of salinization, and actions that could be taken to mitigate it, including technological, policy, and governance interventions and innovations. Similarities and differences across these four groups, and their degree of concordance with measured/modeled SES components, point to actions that could be taken to catalyze collective management of salinization in the region.

The hyporheic exchange below dune-shaped bedforms has a great impact on the stream environment. One of the most important properties of the hyporheic zone is the residence time distribution (RTD) of flow paths in the sediment domain. Here, we evaluate the influence of dimensionless sediment depths d b * = 2 π d b / λ where λ is the dune wavelength and different values of dimensionless groundwater underflow values u b * (similar to dune migration celerity), on the shape of the hyporheic exchange RTD. Empirical RTDs were generated, over a range of combinations between d b * and u b * values, from numerical particle tracking experiments in which 10000 particles were released over a flat domain. These empirical RTDs are represented by different distributions over the range of d b * and u b * . A Fréchet RTD is the best fit for deep beds ( d b * >3.2) and negligible underglow ( u b *

Stream dunes have been widely recognized among the major morphological features driving water exchange between a stream and its sediments, and many modeling studies have been performed to characterize hyporheic exchange induced by this type of bedforms. Despite of these efforts, the high number of factors that affect hyporheic exchange has not been completely addressed yet, mainly because of the simplifying assumptions that are unavoidably required to reduce the complexity of the problem. For instance, the effect of the limited extent of the thickness of the sediment layer on the Residence Time Distribution (RTDs) of hyporheic exchange has not been fully explored. This incomplete knowledge is particularly relevant due to the paramount role of RTDs in controlling biogeochemical reactions in microbiologically active sediments.In this context, this study presents a modeling analysis of RTDs in dune-shaped streambeds of finite depth in the presence of groundwater flow. Numerical simulations of particle tracking have been performed to determine the combined influence of sediment depth and horizontal underflow on the shape of RTDs. Moreover, different analytical distributions (Exponential, Gamma, LogNormal, Fréchet) have been fitted to the numerical RTDs, and the best distribution for each range of dimensionless sediment depth and underflow velocity have been identified on the basis of Anderson-Darling tests.

Inland freshwater salinity is on the rise in many regions across the globe—a phenomenon called the freshwater salinization syndrome (FSS). In this paper we investigate a potential conflict between managing the FSS and indirect potable reuse, the practice of augmenting water supplies through the addition of reclaimed wastewater to surface waters and groundwaters. From time-series data collected over the past 25 years, we quantify the contributions of three salinity sources—a wastewater reclamation facility and two rapidly urbanizing watersheds—to the rising concentration of sodium (a major ion associated with the FSS) in a regionally important drinking water reservoir in the Mid-Atlantic United States. Sodium mass loading to the reservoir is primarily from watershed runoff during wet weather periods and reclaimed wastewater during dry weather periods. Across all timescales evaluated, sodium concentration in the reclaimed wastewater is higher than in outflow from the two watersheds. Sodium in reclaimed wastewater originates from chemicals added during wastewater treatment, industrial and commercial discharges, human excretion, and down drain disposal of drinking water and sodium-rich household products. Thus, numerous opportunities exist to reduce the contribution of indirect potable reuse to sodium pollution at this site, and the FSS more generally. On the ground implementation will require deliberative engagement with a diverse community of watershed stakeholders and careful consideration of the local political, social, and environmental context.

The importance of the benthic biolayer (the first few centimeters in the shallow part of the streambed) comes from the active biogeochemical reactions that happen within this thin layer. Currently, many studies use the simplified approach of using the constant profile to represent the diffusivity in the sedimented; however, other studies claim that the exponential profile is a better representation due to the turbulence penetration into the sediment bed. In this work, we are using an analytical model to simulate the temporal variation of solute concentration in water column in bedform morphology type by adopting two diffusivity profile; constant diffusivity profile, and exponential diffusivity profile. This rigorous analytical framework was built by Grant et al. 2019 (not published yet), and is based on Duhamel’s Theorem. The model is used to fit a set of laboratory data that were performed on streams with dunes type bedforms, where temporal concentration variation is measured in the water column. Based on Root Mean Square Error (RMSE), coefficient of determination (R2), and modified Akaike Information Criterion (AICc), the exponential profile is superior over the whole range of Permeability Reynolds Number, and it can be considered as the best fit for the laboratory data compared to the constant diffusivity. Additionally, the influence of sediment bed depth on the effective diffusivity, and therefore, on the benthic biolayer characteristics is investigated here by running the model with constant diffusivity profile in Infinite and finite sediment bed cases. An indicator () to determine whether the sediment bed depth influences the diffusivity within the sediment domain or not, is introduced here. when this indicator is larger than 1, the sediment bed depth will likely influence the diffusivity within the sediment. Based on our results, our analytical framework can be a predictive tool for the solute transfer into the benthic layer in bedform morphology type.

El tromboembolismo venoso es una causa de morbilidad y mortalidad importante en todo el mundo. El manejo adecuado de los pacientes anticoagulados es fundamental en su evolución. El establecimiento de clínicas de anticoagulación ha demostrado reducir complicaciones y mejorar el manejo de los pacientes que reciben esta terapia cuando se toman decisiones basadas en la evidencia. La presente revisión pretende plantear una guía para facilitar las decisiones, estratificando pacientes según el riesgo de sangrado utilizando escalas previamente validadas para el manejo de pacientes con problemas trombóticos.

INTRODUCTION: Drinking has adverse impacts on health, well-being, education and social outcomes for adolescents. Adolescents in England are among the heaviest drinkers in Europe. Recently, the proportion of adolescents who drink alcohol has fallen, although consumption among those who do drink has actually increased. This trial seeks to investigate how effective and efficient an alcohol brief intervention is with 11-15 years olds to encourage lower alcohol consumption. METHODS AND ANALYSIS: This is an individually randomised two-armed trial incorporating a control arm of usual school-based practice and a leaflet on a healthy lifestyle (excl. alcohol), and an intervention arm that combines usual practice with a 30 min brief intervention delivered by school learning mentors and a leaflet on alcohol. At least 30 schools will be recruited from four regions in England (North East, North West, London, Kent and Medway) to follow-up 235 per arm. The primary outcome is total alcohol consumed in the last 28 days, using the 28 day Timeline Follow Back questionnaire measured at the 12-month follow-up. The analysis of the intervention will consider effectiveness and cost-effectiveness. A qualitative study will explore, via 1:1 in-depth interviews with (n=80) parents, young people and school staff, intervention experience, intervention fidelity and acceptability issues, using thematic narrative synthesis to report qualitative data. ETHICS AND DISSEMINATION: Ethical approval was granted by Teesside University. Dissemination plans include academic publications, conference presentations, disseminating to local and national education departments and the wider public health community, including via Fuse, and engaging with school staff and young people to comment on whether and how the project can be improved. TRIAL REGISTRATION TRIAL: ISRCTN45691494; Pre-results.

This study examined whether there was a significant seasonal variation in objectively measured habitual physical activity and sedentary behavior in young children. Participants were children who attend nursery in Glasgow, Scotland, and measurements were taken using uniaxial accelerometry over 3 to 6 days. There were small but significant seasonal associations with physical activity and sedentary behavior (ANOVA: p < .001 in both cases). Total physical activity (accelerometry cpm) was significantly lower in spring than in summer, fall, and winter. We also found slight but significant seasonal variations in time spent in low-intensity activity and in moderate-to-vigorous-intensity activity. Sedentary time was significantly lower in summer vs. spring and in fall vs. spring. The present study suggests that seasonality plays only a limited role in physical activity and sedentary behavior in young children in our setting. Single measures of these variables should be adequate for research purposes in the absence of marked seasonal variability. In our sample and setting, the limited degree of seasonality precluded identification of major seasonal barriers to and opportunities for physical activity.

The primary aim of this study was to test the validity of two accelerometers, CSA/MTI WAM-7164 and Actiwatch®, against direct observation of physical activity using the Children’s Physical Activity Form (CPAF). CSA/MTI WAM-7164 and Actiwatch accelerometers simultaneously measured activity during structured-play classes in 3- to 4-year olds. Accelerometry output was synchronized to CPAF assessments of physical activity in 78 children. Rank order correlations between accelerometry and direct observation evaluated the ability of the accelerometers to assess total physical activity. Within-child minute-to-minute correlations were calculated between accelerometry output and direct observation. For total physical activity, CSA/MTI output was significantly correlated with CPAF (r = .72, p < .001), but output from the Actiwatch was not (r = .16, p > .05).

BACKGROUND: Chorioangiomas are benign vascular tumors of the placenta. Complications occur when their size exceeds 5 cm. CASE: We report the use of peak systolic velocity in the middle cerebral artery, fetal hemoglobin levels in maternal circulation, and maternal serum alpha-fetoprotein levels in the diagnosis and management of fetal anemia in a patient with a large placental chorioangioma. CONCLUSION: Fetal hemoglobin levels in maternal circulation and abrupt elevations of middle cerebral artery peak velocity may be useful in detecting fetal anemia.

The aim of the work reported here was to investigate the potential benefits of rear suspension systems for mountain bikes and to develop numerical models that could be used in future to help with the design of improved suspension configurations. As the basis for a study of the effect of rear suspensions, two bicycles were chosen: one with full suspension and one with only front suspension (hard tail). Apart from the rear suspension, all other aspects of the bicycles were closely matched. In order to control the number of variables, a special rolling road test rig was used. Eight subjects were asked to ride each bicycle on the rig in random order. Measurements were taken of pedal torque and speed, rear wheel speed, forward thrust at front axle and vertical acceleration at the saddle and handlebars. Physiological measurements were also taken, but these are reported elsewhere. A DADS model of the rolling road rig, bicycle and rider was created and numerical simulations were performed. The results of the numerical simulations compared well with the experimental results. Unmeasured parameters predicted by the DADS model could therefore be used with reasonable confidence to aid the understanding of the suspension performance. Physiological results, mechanical measurements and simulation results all indicate that the full suspension bicycle shows a significant improvement in terms of comfort and energy expenditure when riding over regular bumps. The good correlation between measurement and simulation provides a tool that can be used in future for optimization of bicycle suspension design.

Objective: To test the ability of accelerometry to quantify sedentary behavior in 3- to 4-year-old children. Research Methods and Procedures: We developed a cut-off for accelerometry output (validation study) in 30 healthy 3 to 4 year olds, which provided highest sensitivity and specificity for the detection of sedentary behavior relative to a criterion method of measurement, direct observation using the children's physical activity form. We then cross-validated the cut-off in an independent sample of healthy 3 to 4 year olds (n = 52). Results: In the validation study, optimal sensitivity and specificity for the detection of sedentary behavior were obtained at an accelerometry output cut-off of

The aim of this study was to compare the climbing-specific finger endurance of climbers, rowers and aerobically leg trained athletes. Twenty-seven males aged 21.2 +/- 2.2 years (mean +/- s) volunteered for the study. The participants were intermediate rock climbers (n = 9), rowers (n = 9) and leg trained athletes (n = 9). Maximal voluntary contraction (MVC) was determined on climbing-specific finger apparatus. Endurance isometric exercise was performed at 40% MVC in three tests performed in a random order: (1) sustained exercise; (2) 6 s exercise, 4 s rest; and (3) 18 s exercise, 12 s rest. Pre- and post-exercise blood pressure and blood lactate concentration, together with post-exercise pain perception, were measured. The climbers had a significantly greater MVC (383 +/- 35.6 N) than the rowers (321 +/- 49.5 N, P = 0.007) and aerobically leg trained athletes (288 +/- 60.6 N, P = 0.001). There were no significant differences between the groups in terms of endurance times for any of the tests. In the test with 18 s exercise and 12 s rest, the climbers showed a significantly higher increase in blood lactate concentration, on average, than the rowers by 0.01-0.89 mmol x l(-1) (P = 0.006); there were no significant differences, on average, in the comparisons of climbers and the leg trained athletes and rowers and the leg trained athletes. There were no significant differences in the average changes in blood pressure from rest to post-exercise between any of the groups. Although the climbers had greater MVC on average than the other two groups, there were no significant differences in average endurance times amongthe groups. These findings suggest that training for rock climbing and participation in rock climbing may result in some specific adaptations. However, we acknowledge that this study is descriptive and there is the possibility that differences between groups could be attributed to self-selection.

Objective: To determine whether systematic progressive high-intensity quadriceps training increases leg extensor power and reduces disability in patients rehabilitating after proximal femoral fracture. Design: Open parallel group randomized controlled trial comparing the addition of six weeks quadriceps training (40 patients) with standard physiotherapy alone (40 patients). The training group exercised twice weekly, with six sets of 12 repetitions of knee extension (both legs), progressing up to 80% of their one-repetition maximum. Setting: Orthogeriatric unit, and community follow-up. Subjects: Eighty patients rehabilitating after proximal femoral fracture. Main outcome measures: Measurements of leg extensor power (Nottingham Power Rig), functional mobility (elderly mobility score), disability (Barthel Index) and quality of life (Nottingham Health Profile) were made at baseline, after six weeks (at the end of the intervention) and at 16 weeks. Results: Leg extensor power increased significantly in the quadriceps training group (fractured leg mean improvement at six weeks 157% (standard error 16), nonfractured leg 80% (12)) compared with the control group (63% (11) and 26% (8) respectively, unpaired Student's t-test p = 0.007 and p = 0.01 for between-group comparisons). Significant benefits were maintained at 16 weeks. Quadriceps training resulted in a greater increase in elderly mobility scale score compared with standard rehabilitation (between-group difference of 2.5 (95% CI 1.1,3.8) at week 6 and 1.9 (0.4,3.4) at week 16). Barthel score increased significantly from week 0 to 6 in the quadriceps training group compared with controls (Mann–Whitney U-test p = 0.05). Patients in the quadriceps training group scored significantly better in the energy subscore of the Nottingham Health Profile at the end of follow-up (Mann–Whitney U-test p = 0.0185). Conclusions: Progressive high-intensity quadriceps training in elderly proximal femoral fracture patients increased leg extensor power and reduced disability. This was accompanied by an increase in energy as measured by the Nottingham Health Profile. This intervention may provide a simple practical way of improving outcome in these patients.

The primary aim of this study was to assess the ability of the CSA accelerometer to measure physical activity in preschool children. A secondary aim was to examine inter-instrument differences and the effect of accelerometer placement on output. Eleven subjects (mean age = 4.0 years, SD = 0.4) wore the CSA-7164 for a 45-min preschool exercise class. They were observed throughout the class, and their engagement in activity was quantified using the Children’s Physical Activity Form (CPAF). The effect of accelerometer positioning (left vs. right hip) was assessed in 10 subjects over 2 days. CSA output during the class was highly correlated with the CPAF score (r = 0.87, p < .001), and rank order correlations between the 2 methods were also highly significant (r = 0.79, p < .01). Differences in CSA output between left and right hip reached statistical significance (paired t, p < .05), but these differences were small and probably of limited biological significance. The CSA appears to be an appropriate tool for assessment of physical activity in preschool children, but further studies on stability of activity as measured by CSA, as well as its validity, are urged.

The aim of this study was to investigate the effect of a 12-week exercise programme on the functional status of institutionalised elderly people. Fifteen subjects from two residential homes were assigned to either a control or an exercise group: six exercisers (mean ± sd) 88 ± 5 years and nine controls, 87 ± 4 years. The exercise sessions were carried out twice a week for 12 weeks. The variables measured were distance walked in 15 seconds, single and triple chair rise, and timed stair ascent and descent (all timed using a stopwatch). The exercise sessions consisted of a seven-minute warm-up, a circuit (including walking, chair rising, stair ascent and stair descent) and a ten-minute cool-down. Paired sample and two sample t-tests were used to assess changes. The exercise group improved significantly in all variables post-intervention, while the control group improved significantly in timed stair ascent and timed single chair rise. The exercise group did not significantly improve over the controls in any of the variables, except for walking. Confidence intervals of 95% showed that on average, the exercisers improved between 2 and 5 metres more than the controls in the walking test. The improvement in walking performance in the exercise group may result in increased physical activity and an enhanced lifestyle.

The aim of this study was to assess the relationship between a number of physiological variables and running velocity at 3 km (v-3km) in a group of male runners. Sixteen well-trained middle- and long-distance runners (mean +/-s: age 22.4 +/- 4.2 years, body mass 63.5 +/- 6.2 kg, VO2 max 73.3 +/- 6.7 ml kg-1 min-1) underwent laboratory treadmill tests to determine their maximum oxygen uptake (VO2 max), running economy at three submaximal velocities (12.9, 14.5 and 16.1 km h-1 or 14.5, 16.1 and 17 km h-1), predicted velocity at VO2 max (v-VO2max), velocity (v-Tlac) and VO2 (VO2-Tlac) at the lactate threshold and their velocity (v-4mM) and VO2 (VO2-4mM) at a blood lactate concentration of 4 mM. Distance running performance was determined by 3 km time-trials on an indoor 200 m track for which the average time was 9.46 +/- 0.74 min. The mean (+/-s) velocities for v-Tlac, v-4mM and v-VO2max were 16.0 +/- 1.8, 17.1 +/- 1.9 and 20.7 +/- 2.1 km h-1 respectively, all significantly different on average (all P0.05) from that for v-3km (19.1 +/- 1.5 km h-1). Many of these physiological variables were found to be individually (and significantly at 5%) related to v-3km. The best single predictors of v-3km were v-Tlac and v-4mM (both with a sample correlation, r2 of 0.93), while v-VO2max was slightly poorer (r = 0.86). Neither VO2 max nor running economy was strongly correlated with v-3km. A stepwise multiple-regression analysis revealed that v-Tlac alone was the best single predictor of v-3km and explained 87% of the variability in 3 km running velocity, while the addition of any of the other physiological variables did not significantly improve the prediction of v-3km. We conclude that, in a group of well-trained runners, the running velocity at the lactate threshold was all that was required to explain a large part of the variability in 3 km running performance.