Screening of Swiss hot spring resorts for potentially pathogenic free-living amoebae

Free-living amoebae (FLA) belonging to Acanthamoeba spp., Naegleria fowleri, Balamuthia mandrillaris, and Sappinia pedata are known to cause infections in humans and animals leading to severe brain pathologies. Worldwide, warm aquatic environments have been found to be suitable habitats for pathogenic FLA. The present study reports on screening for potentially pathogenic FLA in four hot spring resorts in Switzerland. Water samples were taken from water filtration units and from the pools, respectively. Amoebae isolated from samples taken during, or before, the filtration process were demonstrated to be morphologically and phylogenetically related to Stenoamoeba sp., Hartmannella vermiformis, Echinamoeba exundans, and Acanthamoeba healyi. With regard to the swimming pools, FLA were isolated only in one resort, and the isolate was identified as non-pathogenic and as related to E. exundans. Further investigations showed that the isolates morphologically and phylogenetically related to A. healyi displayed a pronounced thermotolerance, and exhibited a marked in vitro cytotoxicity upon 5-day exposure to murine L929 fibroblasts. Experimental intranasal infection of Rag2-immunodeficient mice with these isolates led to severe brain pathologies, and viable trophozoites were isolated from the nasal mucosa, brain tissue, and lungs post mortem. In summary, isolates related to A. healyi were suggestive of being potentially pathogenic to immunocompromised persons. However, the presence of these isolates was limited to the filtration units, and an effective threat for health can therefore be excluded.

Juvenile spring eruption: an outbreak report and systematic review of the literature

Juvenile spring eruption of the helices of the ears is a distinctive sun-induced condition appearing on the light-exposed skin of the ears, typically in boys and young men in early spring.

Break detection of annual Swiss temperature series

[1] Instrumental temperature series are often affected by artificial breaks (“break points”) due to (e.g.,) changes in station location, land-use, or instrumentation. The Swiss climate observation network offers a high number and density of stations, many long and relatively complete daily to sub-daily temperature series, and well-documented station histories (i.e., metadata). However, for many climate observation networks outside of Switzerland, detailed station histories are missing, incomplete, or inaccessible. To correct these records, the use of reliable statistical break detection methods is necessary. Here, we apply three statistical break detection methods to high-quality Swiss temperature series and use the available metadata to assess the methods. Due to the complex terrain in Switzerland, we are able to assess these methods under specific local conditions such as the Foehn or crest situations. We find that the temperature series of all stations are affected by artificial breaks (average = 1 break point / 48 years) with discrepancies in the abilities of the methods to detect breaks. However, by combining the three statistical methods, almost all of the detected break points are confirmed by metadata. In most cases, these break points are ascribed to a combination of factors in the station history.

Spring

Mixed Media/Mylar

Break

Coffee, tea, and snacks will be available for attendees during this break.

Break

Coffee, tea, and snacks will be available for attendees during this break.

Using water balance models to approximate the effects of climate change on spring catchment discharge : Mt. Hanang, Tanzania

This project addresses the potential impacts of changing climate on dry-season water storage and discharge from a small, mountain catchment in Tanzania. Villagers and water managers around the catchment have experienced worsening water scarcity and attribute it to increasing population and demand, but very little has been done to understand the physical characteristics and hydrological behavior of the spring catchment. The physical nature of the aquifer was characterized and water balance models were calibrated to discharge observations so as to be able to explore relative changes in aquifer storage resulting from climate changes. To characterize the shallow aquifer supplying water to the Jandu spring, water quality and geochemistry data were analyzed, discharge recession analysis was performed, and two water balance models were developed and tested. Jandu geochemistry suggests a shallow, meteorically-recharged aquifer system with short circulation times. Baseflow recession analysis showed that the catchment behavior could be represented by a linear storage model with an average recession constant of 0.151/month from 2004-2010. Two modified Thornthwaite-Mather Water Balance (TMWB) models were calibrated using historic rainfall and discharge data and shown to reproduce dry-season flows with Nash-Sutcliffe efficiencies between 0.86 and 0.91. The modified TMWB models were then used to examine the impacts of nineteen, perturbed climate scenarios to test the potential impacts of regional climate change on catchment storage during the dry season. Forcing the models with realistic scenarios for average monthly temperature, annual precipitation, and seasonal rainfall distribution demonstrated that even small climate changes might adversely impact aquifer storage conditions at the onset of the dry season. The scale of the change was dependent on the direction (increasing vs. decreasing) and magnitude of climate change (temperature and precipitation). This study demonstrates that small, mountain aquifer characterization is possible using simple water quality parameters, recession analysis can be integrated into modeling aquifer storage parameters, and water balance models can accurately reproduce dry-season discharges and might be useful tools to assess climate change impacts. However, uncertainty in current climate projections and lack of data for testing the predictive capabilities of the model beyond the present data set, make the forecasts of changes in discharge also uncertain. The hydrologic tools used herein offer promise for future research in understanding small, shallow, mountainous aquifers and could potentially be developed and used by water resource professionals to assess climatic influences on local hydrologic systems.

Are full or empty beer bottles sturdier and does their fracture-threshold suffice to break the human skull?

Beer bottles are often used in physical disputes. If the bottles break, they may give rise to sharp trauma. However, if the bottles remain intact, they may cause blunt injuries. In order to investigate whether full or empty standard half-litre beer bottles are sturdier and if the necessary breaking energy surpasses the minimum fracture-threshold of the human skull, we tested the fracture properties of such beer bottles in a drop-tower. Full bottles broke at 30 J impact energy, empty bottles at 40 J. These breaking energies surpass the minimum fracture-threshold of the human neurocranium. Beer bottles may therefore fracture the human skull and therefore serve as dangerous instruments in a physical dispute.

SPRING DISCHARGE MONITORING IN LOW-RESOURCE SETTINGS: A CASE STUDY OF CONCEPCIÓN CHIQUIRICHAPA, GUATEMALA

Water springs are the principal source of water for many localities in Central America, including the municipality of Concepción Chiquirichapa in the Western Highlands of Guatemala. Long-term monitoring records are critical for informed water management as well as resource forecasting, though data are scarce and monitoring in low-resource settings presents special challenges. Spring discharge was monitored monthly in six municipal springs during the author’s Peace Corps assignment, from May 2011 to March 2012, and water level height was monitored in two spring boxes over the same time period using automated water-level loggers. The intention of this approach was to circumvent the need for frequent and time-intensive manual measurement by identifying a fixed relationship between discharge and water level. No such relationship was identified, but the water level record reveals that spring yield increased for four months following Tropical Depression 12E in October 2011. This suggests that the relationship between extreme precipitation events and long-term water spring yields in Concepción should be examined further. These limited discharge data also indicate that aquifer baseflow recession and catchment water balance could be successfully characterized if a long-term discharge record were established. This study also presents technical and social considerations for selecting a methodology for spring discharge measurement and highlights the importance of local interest in conducting successful community-based research in intercultural low-resource settings.