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Direct cell-to-cell spreading of Listeria monocytogenes requires the bacteria to induce actin-based finger-like membrane protrusions in donor host cells that are endocytosed through caveolin-rich membrane invaginations by adjacent receiving cells. An actin shell surrounds these endocytic sites; however, its structure, composition, and functional significance remain elusive. Here, we show that the formin mDia1, but surprisingly not the Arp2/3 complex, is enriched at the membrane invaginations generated by L. monocytogenes during HeLa and Jeg-3 cell infections. Electron microscopy reveals a band of linear actin filaments that run along the longitudinal axis of the invagination membrane. Mechanistically, mDia1 expression is vital for the assembly of this F-actin shell. mDia1 is also required for the recruitment of Filamin A, a caveola-associated F-actin cross-linking protein, and caveolin-1 to the invaginations. Importantly, mixed-cell infection assays show that optimal caveolin-based L. monocytogenes cell-to-cell spreading correlates with the formation of the linear actin filament-containing shell by mDia1. IMPORTANCE Listeria monocytogenes spreads from one cell to another to colonize tissues. This cell-to-cell movement requires the propulsive force of an actin-rich comet tail behind the advancing bacterium, which ultimately distends the host plasma membrane into a slender bacterium-containing membrane protrusion. These membrane protrusions induce a corresponding invagination in the membrane of the adjacent host cell. The host cell that receives the protrusion utilizes caveolin-based endocytosis to internalize the structures, and filamentous actin lines these membrane invaginations. Here, we set out to determine the structure and function of this filamentous actin “shell.” We demonstrate that the formin mDia1, but not the Arp2/3 complex, localizes to the invaginations. Morphologically, we show that this actin is organized into linear arrays and not branched dendritic

The Gorge of the Yarmouk River is the drainage base for groundwater lowing from diferent natural replenishment areas and aquifer lithologies. For the three riparian states (Syria, Jordan and Israel), the uncertainty of groundwater origin imposes diiculties on the management of the water lowing in the Basin towards the Gorge. In the Yarmouk basin, groundwater replenishment areas are lanks of Mt. Hermon, the Golan Heights, Jebel Druze and the Ajloun Dome. The catchment lithology of these areas is mostly alkali olivine basalts and partly limestones. Most of the groundwater accumulates in Upper Cretaceous limestone aquifers (A7/B2) underlying the basalts. The chemistry of groundwater lowing from the Golan Heights and from Jebel Druze indicates origin from basaltic rocks. In the Ajloun, the chemistry indicates mixing of water from basalts and limestones with local dissolution of gypsum and halite. The Cretaceous outcrops in the southern and southeastern lanks of the Palmyra structure are the origin of the northern contributors of groundwater. The Mg2+/Ca2+ values of groundwater from the Hauran, Golan and Ajloun regions scatter between 1.17 and 0.54. Samples from the Ajloun and Golan are characterized by very low values of 0.54–0.61 indicating signiicant dissolution of gypsum/anhydrite. Albitization of plagioclase from basalts is observed in the Golan region by decrease of Na+/Cl− and corresponding increase of Ca2+/Cl−. Correlation plots between various ions and ionic ratios are presented to diferentiate between the diferent sources of groundwater emerging in the Lower Yarmouk Gorge (LYG) which is an important step for responsible management of transboundary water resources in this region. The presented methodology was found by the authors as very useful for identifying diferent groundwater bodies in multi-aquifer systems by Möller et al. (J Hydrol Reg Stud 5:33–47, 2016).

Recent studies investigating groundwater parameters, e.g., heads, chemical composition, and heat transfer, argued that groundwater flow paths in the Lower Yarmouk Gorge (LYG) area are controlled by geological features such as faults or dikes. However, the nature of such features, as well as their exact locations, were so far unknown. In the present paper, we propose a new fault pattern in the LYG area by compiling and revising geological and geophysical data from the study area, including borehole information, geological map cross sections, and seismic data from the southern Golan Heights and northern Ajloun mountains. The presented pattern is composed of strike–slip and thrust faults, which are associated with the Dead Sea transform system and with the Kinnarot pull-apart basin. Compressional and tensional structures developed in different places, forming a series of fault blocks probably causing a non-uniform spatial hydraulic connection between them. This study provides a coarse fault-block model and improved structural constraints that serve as fundamental input for future hydrogeological modeling which is a suggested solution for an enigmatic hydrological situation concerning three riparian states (Syria, Jordan, and Israel) in a water-scarce region. In areas of water scarcity and transboundary water resources, transient 3-D flow simulations of the resource are the most appropriate solution to understand reservoir behavior. This is an important tool for the development of management strategies. However, those models must be based on realistic geometry, including structural features. The study at the LYG is intended to show the importance of such kinds of structural investigations for providing the necessary database in geologically stressed areas without sufficient data. Furthermore, during the hydrogeological investigation, a mismatch with results of pull-apart basin rim fault evolution studies was discovered. We argue that this mismatch may result from the se

The Lower Jordan Valley in the Middle East comprises parts of Israel, Jordan and the Palestinian Territories and is amongst the water scarcest regions worldwide. As the average water availability per person is below 150 m³/year, this region is facing absolute water scarcity. The water resource systems are overexploited and subject to further stress through high population growth, climate change and the recent migration of refugees from Syria. Declining water levels of the Dead Sea and within the regional aquifers are visible evidence of overexploitation. Further, salinization and contamination including pharmaceutical residues in surface and groundwater indicate the strong deterioration of water quality by anthropogenic activities. Integrated Water Resource Management (IWRM) is a concept to address these water related issues but needs to be incorporated into the water strategies of the riparian states. SMART (Sustainable Management of Available Resources with Innovative Technologies) is a research and development project within the framework of IWRM and has the overall goal to develop a transferable concept for a sustainable water resource management in the Lower Jordan Valley. Besides natural available freshwater, unconventional sources such as treated waste water, artificially recharged groundwater, and desalinated brackish groundwater are considered. Based on detailed water balances, management concepts have been developed and applied to allow the assessment of the current state of the water resources, as well as the future development, taking the actions of the respective water strategy into account. The SMART approach is transferable to other regions in the world suffering under natural and/or manmade water scarcity.

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The overall aim of the this study, which was conducted within the framework of the multilateral IWRM project SUMAR, was to expand the scientific basement to quantify surface- and groundwater fluxes towards the hypersaline Dead Sea. The flux significance for the arid vicinity around the Dead Sea is decisive not only for a sustainable management in terms of water availability for future generations but also for the resilience of the unique ecosystems along its coast.Coping with different challenges interdisciplinary methods like (i) hydrogeochemical fingerprinting, (ii) satellite and airborne-based thermal remote sensing, (iii) direct measurement with gauging station in ephemeral wadis and a first multilateral gauging station at the river Jordan, (iv) hydro-bio-geochemical approach at submarine and shore springs along the Dead Sea and (v) hydro(geo)logical modelling contributed to the overall aim.As primary results, we deduce that the following:(i)Within the drainage basins of the Dead Sea, the total mean annual precipitation amounts to 300 mm a− 1 west and to 179 mm a− 1 east of the lake, respectively.(ii)The total mean annual runoff volumes from side wadis (except the Jordan River) entering the Dead Sea is approximately 58–66 × 106 m3 a− 1 (western wadis: 7–15 × 106 m3 a− 1; eastern wadis: 51 × 106 m3 a− 1).(iii)The modelled groundwater discharge from the upper Cretaceous aquifers in both flanks of the Dead Sea towards the lake amounts to 177 × 106 m3 a− 1.(iv)An unexpected abundance of life in submarine springs exists, which in turn explains microbial moderated geo-bio-chemical processes in the Dead Sea sediments, affecting the highly variable chemical composition of on- and offshore spring waters.The results of this work show a promising enhancement of describing and modelling the Dead Sea basin as a whole.

Hot and salty waters occur in the surroundings of the Lake Tiberias. Transient numerical simulations of thermally-driven flow without salinity effects show that mixed convection can explain the upsurge of thermal waters through permeable faults and the high temperature gradient in the Lower Yarmouk Gorge (LYG). It turns out that by including salinity effects, the flow patterns differ from those of a purely thermal regime because heavy brines dampen upward buoyant flow and convective cells. Accordingly, the fault permeability had to be increased to restore a good fit with the measured temperatures. This further supports the hypothesis that the high temperature gradient in the LYG is likely due to fractures or faults in that area. The thermohaline simulations also suggest that the derivatives of relic seawater brines are the major source of salinity. Deep brines leaching salt diapirs cannot reach the surface. However, the presence of local shallower salt bodies below the lake can potentially contribute to the salinity of the western spring and well waters, though in very small amount. This is in agreement with geochemical data according to which the major source of the brines of the Tiberias Basin represents seawater evaporation brines. Besides being of importance for understanding the hydrogeological processes that salinize Lake Tiberias, the presented simulations provide a real-case example illustrating large-scale fluid patterns due to only one source of buoyancy (heat) and those that are additionally coupled to salinity.

Formal Aspects in Security and Trust : Third International Workshop, FAST 2005, 08 oktober 2008, Contains fulltext : 76017.pdf (author's version ) (Open Access)