Microbial and Chemical Characterization of Underwater Fresh Water Springs in the Dead Sea

Due to its extreme salinity and high Mg concentration the Dead Sea is characterized by a very low density of cells most of which are Archaea. We discovered several underwater fresh to brackish water springs in the Dead Sea harboring dense microbial communities. We provide the first characterization of these communities, discuss their possible origin, hydrochemical environment, energetic resources and the putative biogeochemical pathways they are mediating. Pyrosequencing of the 16S rRNA gene and community fingerprinting methods showed that the spring community originates from the Dead Sea sediments and not from the aquifer. Furthermore, it suggested that there is a dense Archaeal community in the shoreline pore water of the lake. Sequences of bacterial sulfate reducers, nitrifiers iron oxidizers and iron reducers were identified as well. Analysis of white and green biofilms suggested that sulfide oxidation through chemolitotrophy and phototrophy is highly significant. Hyperspectral analysis showed a tight association between abundant green sulfur bacteria and cyanobacteria in the green biofilms. Together, our findings show that the Dead Sea floor harbors diverse microbial communities, part of which is not known from other hypersaline environments. Analysis of the water’s chemistry shows evidence of microbial activity along the path and suggests that the springs supply nitrogen, phosphorus and organic matter to the microbial communities in the Dead Sea. The underwater springs are a newly recognized water source for the Dead Sea. Their input of microorganisms and nutrients needs to be considered in the assessment of possible impact of dilution events of the lake surface waters, such as those that will occur in the future due to the intended establishment of the Red Sea−Dead Sea water conduit

Patient and provider perspectives on cellular phone-based technology to improve HIV treatment adherence

Innovative techniques, potentially using technology, to improve adherence to antiretroviral therapy (ART), may help patients with HIV who struggle with self-care. This qualitative study compared patient and provider participants’ perspectives on ART adherence and text messaging as a tool to promote adherence. Thirteen providers and 14 HIV-infected patients identified four main themes: 1). facilitators and 2). barriers to using text message reminders as a medium for ART medication reminders; 3). framing of text message reminders; and 4). patient responsibility and autonomy in management of their health and wellness. Ease of use, access, convenience, and confidentiality were cited as benefits of a text message based adherence intervention; while access, cost, difficulty manipulating cellular phones, lack of knowledge/education, and confidentiality were cited as potential barriers. Providers, but not patients, also identified patient apathy and time burden as potential barriers to a text message based adherence reminder system. Patients and providers felt that personalization of messages, attention to timing, and confidentiality of messages were key factors for a successful text message based adherence reminder system. Both providers and patients felt that patient responsibility and autonomy over an individual’s own health care is an important issue in adherence to medical care. The majority of patients and providers felt that a text message based adherence reminder system would be beneficial. While patients and providers had many similar views on factors influencing adherence with ART and the use of text messaging to improve adherence, there were some divergent views between the two groups

Anticipating and managing engineering problems in the complex karst environment

Karst environments are characterized by distinctive landforms and a peculiar hydrologic behavior dominated by subsurface drainage. Karst systems can be extremely complex, heterogeneous, and unpredictable due to the wide range of geological and hydrological controlling factors. The great variability results in serious problems for engineers, and in difficulties to characterize the karstified rock masses, and in designing the engineering works to be performed. The design and development of engineering projects in karst environments require specific approaches aimed at minimizing the detrimental effects of hazardous processes and environmental problems. Further, karst aquifers (that provide approximately 20–25 % of the world’s drinking water) are extremely vulnerable to pollution, due to the direct connection between the surface and the subsurface drainage, the rapidity of the water flow in conduit networks, and the very low depuration capability. Sinkholes are the main source of engineering problems in karst environments, and may cause severe damage in any human structure. The strategies and solutions that may be applied to mitigate sinkhole problems are highly variable and largely depend on the kind of engineering structure, the karst setting, and the typology and size of the sinkholes. A sound geological model, properly considering the peculiarities of karst and its interactions with the human environment, is essential for the design of cost-effective and successful risk reduction programs. Due to the unique direct interaction between surface and subsurface environments, and the frequent ground instability problems related to underground karstification, management of karst environments is a very delicate matter. Disregarding such circumstances in land-use planning and development inevitably results in severe problems with high economic impacts. Karst environments require specific investigation methods in order to properly manage and safeguard the sensitive geo-ecosystems and natural resources associated with the