Hydrologic modeling of a small ungauged basin in the Sahel: unique calibration and results

2014 Spring.Includes bibliographical references.The Sahelian region of Africa is a geographic belt directly south of the Sahara, connecting the desert to the wetter Sudanian and Guinean savannas to the South. The region is semi-arid, receiving only 300-600 mm of precipitation on average annually. In addition, the Sahel experiences severe dry seasons (7-9 months) with little to no rain. Measurement stations in the region are scarce and reliable data is often difficult to obtain. It is common for drainage basins throughout many parts of the world to be ungauged or gauged but deteriorating. Conventional hydrologic modeling techniques to calibrate and verify basin parameters are rarely applicable in these cases. This problem is exacerbated when human-induced changes to the land surface and climate change impacts lead to increased uncertainty. A recent hydrologic regime shift in parts of the Sahel has been observed and is the basis for this study. Traditionally, a lack of perennial water sources in the region limited settlement, and only seasonal grazing was commonplace. However, many of the previously ephemeral lakes in the region have become perennial or less drastically ephemeral, and settlements have begun to appear in these locations. Hypotheses of how this regime shift occurred, or whether this trend will continue were tested with a calibrated hydrologic model. This study will: (1) address briefly the difficulty in calibrating hydrologic models in ungauged basins; (2) share the results of a unique calibration procedure; and (3) test project hypotheses using the calibrated hydrologic model in a case study of a small lake basin in Northern Mali

Low-Tech Coconut Shell Activated Charcoal Production

Water treatment technologies in the developing world typically focus on removing two types of impurities from water sources: suspended solids and microbial pathogens. However, as industrialization and high-input agriculture has expanded into the developing world, chemical impurities such as pesticides, herbicides, and fertilizers have found their way into drinking water supplies and have been linked to severe health-related issues. Activated carbon has the capacity to remove these problematic chemicals from water sources. A simple, inexpensive, and effective activated carbon production process using local agricultural waste byproducts was assessed for the community of Bluefields, Nicaragua. Coconut shell charcoal was produced on site, and various chemical activation techniques were investigated. The adsorption capacity of three separate chemically activated coconut shell charcoals was analyzed, with sodium chloride—common table salt—being the most efficient and cost effective activating agent

High-Intensity Variable Stepping Training in Patients With Motor Incomplete Spinal Cord Injury: A Case Series

Background and Purpose: Previous data suggest that large amounts of high-intensity stepping training in variable contexts (tasks and environments) may improve locomotor function, aerobic capacity, and treadmill gait kinematics in individuals poststroke. Whether similar training strategies are tolerated and efficacious for patients with other acute-onset neurological diagnoses, such as motor incomplete spinal cord injury (iSCI), is unknown. Individuals with iSCI potentially have greater bilateral impairments. This case series evaluated the feasibility and preliminary short- and long-term efficacy of highintensity variable stepping practice in ambulatory participants for more than 1 year post-iSCI. Case Series Description: Four participants with iSCI (neurological levels C5-T3) completed up to 40 one-hour sessions over 3 to 4 months. Stepping training in variable contexts was performed at up to 85% maximum predicted heart rate, with feasibility measures of patient tolerance, total steps/session, and intensity of training. Clinical measures of locomotor function, balance, peak metabolic capacity, and gait kinematics during graded treadmill assessments were performed at baseline and posttraining, with more than 1-year follow-up. Outcomes: Participants completed 24 to 40 sessions over 8 to 15 weeks, averaging 2222 ± 653 steps per session, with primary adverse events of fatigue and muscle soreness. Modest improvements in locomotor capacity where observed at posttraining, with variable changes in lower extremity kinematics during treadmill walking. Discussion: High-intensity, variable stepping training was feasible and tolerated by participants with iSCI although only modest gains in gait function or quality were observed. The utility of this intervention in patients with more profound impairments may be limited

Development and validation of a physical activity monitor for use on a wheelchair

Study design: Keeping physically active is important for people who mobilize using a wheelchair. However, current tools to measure physical activity in the wheelchair are either not validated or limited in their application. The purpose of this study was to develop and validate a monitoring system to measure wheelchair movement.<p></p> Methods: The system developed consisted of a tri-axial accelerometer placed on the wheel of a wheelchair and an analysis algorithm to interpret the acceleration signals. The two accelerometer outputs in the plane of the wheel were used to calculate the angle of the wheel. From this, outcome measures of wheel revolutions, absolute angle and duration of movement were derived and the direction of movement (forwards or backwards) could be distinguished. Concurrent validity was assessed in comparison with video analysis in 14 people with spinal cord injury using their wheelchair on an indoor track and outdoor wheelchair skills course. Validity was assessed using intraclass correlation coefficients (ICC(2,1)) and Bland–Altman plots.<p></p> Results: The monitoring system demonstrated excellent validity for wheel revolutions, absolute angle and duration of movement (ICC(2,1)>0.999, 0.999, 0.981, respectively) in both manual and powered wheelchairs, when the wheelchair was propelled forwards and backwards, and for movements of various durations.<p></p> Conclusion: This study has found this monitoring system to be an accurate and objective tool for measuring detailed information on wheelchair movement and manoeuvring regardless of the propulsion technique, direction and speed

A descriptive study of older adults with persistent pain: Use and perceived effectiveness of pain management strategies [ISRCTN11899548]

BACKGROUND: Persistent pain is a common, often debilitating, problem in older adults; however, few studies have focused on the experiences of older adults in managing their pain. The objective of this study was to describe the use and perceived effectiveness of pain management strategies in a sample of older adults and to explore the associations of these variables with demographic and psychosocial characteristics. METHODS: Adults ≥ 65 years old and living in retirement facilities who reported persistent pain (N = 235, mean age = 82 years, 84% female, 94% white) completed measures of demographics, pain, depression, self-efficacy for managing pain, and a Pain Management Strategies Survey. Participants identified current and previous-year use of 42 pain management strategies and rated helpfulness of each on a 5-point scale. RESULTS: Acetaminophen, regular exercise, prayer, and heat and cold were the most frequently used pain management strategies (61%, 58%, 53%, and 48%, respectively). Strategies used by >25% of the sample that were rated moderately or more helpful (i.e., >2 on a 0 to 4 scale) were prayer [mean (SD) = 2.9 (0.9)], opioids [2.6 (0.8)], regular exercise [2.5 (1.0)], heat/cold [2.5 (1.0)], nonsteroidal anti-inflammatory drugs [2.4 (1.0)], and acetaminophen [2.3 (1.0)]. Young-old (65–74 years) study participants reported use of more strategies than did old-old (85+ years) participants (p = .03). Perceived helpfulness of strategy use was significantly associated with pain intensity (r = -.14, p < .0001), self-efficacy (r = .28, p < .0001), and depression (r = -.20, p = .003). CONCLUSION: On average, older adults view the strategies they use for persistent pain as only moderately helpful. The associations between perceived helpfulness and self-efficacy and depression suggest avenues of pain management that are focused less on specific treatments and more on how persons with persistent pain think about their pain

The Need to Travel: Malian Women Shuttle Traders, Autonomy and (Mis)trust in Neoliberal Dakar

Recent infrastructural developments in Senegal have severely impacted on the livelihoods of female bana-banas from Mali, a group of mobile traders operating in the Mali–Dakar corridor: transportation costs have significantly increased, travelling has become a more exhausting experience, and fatal accidents have become more frequent during journeys. Why did the bana-banas continue these arduous journeys? Why was their physical presence required in Dakar, and why did they not rely more extensively on social networks to facilitate their transnational trade? This article examines the conditions of autonomy, flexibility and limited trust that characterized the bana-banas’ livelihoods and necessitated their continued mobility from Mali. The recent infrastructural transformations have led to an increased commercialization and disarticulation of Malian trade networks in the Senegalese capital, and, due to personal circumstances, the women have often been cut off from networks. However, unlike general expectations of the ways in which networks evolve under conditions of neoliberalism, the bana-banas have not turned to personalized relationships of trust in Dakar, which might have facilitated their trade from a distance. The article contributes to the growing literature on social networks and trust by exploring how transnational trade does and does not work at this historical moment and in the context of gendered constraints