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A large [1 1 0] unidirectional ammonium nickel sulfate (ANSH) single crystal was grown from aqueous solution by a novel technique called Sankaranarayanan-Ramasamy (S-R) method. Using a [1 1 0] oriented ANSH seed crystal mounted at the bottom of a glass ampoule, a single crystal of 17 mm in diameter and 95 mm in length was grown by this method. The optical transmission spectrum of the grown crystal demonstrates the characteristics of ultraviolet filters. Thermogravimetric curve of the grown crystal showed its dehydration temperature of 95 °C. [ABSTRACT FROM AUTHOR]

The underlying mechanism of oil recovery by low-salinity-water injection (LSWI) is still unknown. It would, therefore, be difficult to predict the performance of reservoirs under LSWI. A number of mechanisms have been proposed in the literature, but these are controversial and have largely ignored crucial fluid/fluid interactions. Our direct-flow-visualization investigations (Emadi and Sohrabi 2013) have revealed that a physical phenomenon takes place when certain crude oils are contacted by low-salinity water, leading to a spontaneous formation of micelles that can be seen in the form of microdispersions in the oil phase. In this paper, we present the results of a comprehensive study that includes experiments at different scales designed to systematically investigate the role of the observed crude-oil/brine interaction and micelle formation in the process of oil recovery by LSWI. The experiments include direct-flow (micromodel) visualization, crudeoil characterization, coreflooding, and spontaneous-imbibition experiments. We establish a clear link between the formation of these micelles, the natural surface-active components of crude oil, and the improvement in oil recovery because of LSWI. We present the results of a series of spontaneous- and forced-imbibition experiments carefully designed with reservoir cores to investigate the role of the microdispersions in wettability alteration and oil recovery. To further assess the significance of this mechanism, in a separate exercise, we eliminate the effect of clay by performing an LSWI experiment in a clay-free core. Absence of clay minerals is expected to significantly reduce the influence of the previously proposed mechanisms for oil recovery by LSWI. Nevertheless, we observe significant additional oil recovery compared with high-salinitywater injection (HSWI) in the clay-free porous medium. The additional oil recovery is attributed to the formation of micelles stemming from the crude-oil/brine-interaction mechanism described in this work and our previous related publications. Compositional analyses of the oil produced during this coreflood experiment indicate that the natural surface-active compounds of the crude oil had been desorbed from the rock surfaces during the LSWI period of the experiment when the additional oil was produced. The results of this study present new insights into the fundamental mechanisms involved in oil recovery by LSWI and new criteria for evaluating the potential of LSWI for application in oil reservoirs. The fluid/fluid interactions revealed in this research can be applied to oil recovery from both sandstone and carbonate oil reservoirs because they are mainly derived from fluid/fluid interactions that control wettability alteration in both sandstone and carbonate rocks. [ABSTRACT FROM AUTHOR]

Background: In late‐onset Alzheimer's disease (LOAD), the causal mechanisms of synaptic dysfunction underlying memory deficits that lead to dementia remain unclear. Genetic studies of LOAD patients identified gene variants associated with AD. Now it is necessary to translate the genotype into the mechanism of synaptic dysfunction. Here we investigated the impact of the putative LOAD risk factor CD2AP loss of function. We hypothesized that CD2AP might regulate spinal actin since CD2AP is a regulator of actin dynamics in non‐neuronal cells, and the actin cytoskeleton dynamics is essential for spine plasticity. Method: We have used wild‐type mouse primary cortical neurons after differentiation for 15‐21 DIV. To knockdown CD2AP, we infected primary neurons with lentivirus expressing GFP and shCD2AP or non‐targeting shRNA as control. We used immunofluorescence microscopy, using epifluorescence and confocal microscopy, and quantitative morphologic and subcellular analysis using ICY and Imaris software to analyze CD2AP synaptic localization, synapses and spines density, as well as spinal F‐actin. Result: We discovered that CD2AP is present in spines. CD2AP knockdown reduced spines density. In contrast, CD2AP overexpression increased spine density. Morphologically, CD2AP overexpression enlarged spine heads. Synapses density was, like spines, reduced by CD2AP knockdown. Mechanistically, we found that spinal F‐actin decreased by CD2AP knockdown and increased upon CD2AP overexpression. Conclusion: These results indicate that CD2AP regulates spine morphology and thus synapses, likely by regulating actin dynamics at spines. Overall CD2AP variants may contribute to LOAD development by directly interfering with synapses. [ABSTRACT FROM AUTHOR]

Background: In late‐onset Alzheimer's disease (LOAD) the causal mechanisms of synaptic dysfunction that underlie the memory deficits that lead to dementia are not established. The search for genetic risk factors in LOAD led to the identification of more than 20 genes and three main mechanisms: endocytic trafficking, lipid metabolism and immune response. Here we aim to establish causality between a mutation in CD2AP, one of the endocytic trafficking risk factors, and synaptic dysfunction. Since CD2AP is a regulator of the actin cytoskeleton dynamics which is essential for spine morphology, we hypothesize that a LOAD mutation CD2AP may impact spines by deregulating actin. Method: We have analyzed synapses and spines density as well as spinal actin in cortical mouse primary neurons either transiently overexpressing wild‐type and mutant CD2AP‐GFP as well as GFP as control or infected with lentivirus expressing GFP and shCD2AP or non‐targeting shRNA as control. Moreover, we investigated CD2AP synaptic localization by immunofluorescence microscopy. We used quantitative single‐cell analysis using ICY and Imaris software. Result: We discovered that a pool of CD2AP is present in spines; and that both CD2AP wild‐type and mutant are significantly enriched in spines. Spines length decreased with larger spine heads, by CD2AP wild‐type and more pronouncedly by mutant CD2AP overexpression. Indicating that CD2AP might function at synapses, by regulating spine morphology. Indeed, synapses density was reduced by CD2AP knockdown. Mechanistically, we found that spinal F‐actin increased by CD2AP wild‐type and more pronouncedly by mutant CD2AP overexpression compared to control neurons. We are currently investigating whether spinal F‐actin is altered by CD2AP knockdown. Conclusion: These results indicate that CD2AP regulates spine morphology and thus synapses. A LOAD mutant CD2AP may interfere with its function by dysregulating actin dynamics at spines. Overall CD2AP variants may contribute to LOAD development by directly interfering with synapses. References: (1) Ubelmann, Florent, et al. "Bin1 and CD2AP polarise the endocytic generation of beta‐amyloid." EMBO reports 18.1 (2017): 102‐122. (2) Hollingworth, Paul, et al. "Common variants at ABCA7, MS4A6A/MS4A4E, EPHA1, CD33 and CD2AP are associated with Alzheimer's disease." Nature genetics 43.5 (2011): 429. [ABSTRACT FROM AUTHOR]

We determined if colour, category (e.g., food packaging) or intertidal activity could explain the occurrence of litter with acute levels of metals. Six beaches were sampled; an industrial site, a local and remote park and three beaches. Food packaging accounted for 66% of litter with acute levels of metals found in 10% of samples. Acute levels were independent of colour and category, but dependent on intertidal region and its anthropogenic use. Litter with acute levels of cadmium and lead were recovered from the industrial intertidal and high concentrations of zinc and cadmium associated with candy wrappers were found on recreational beaches. In addition to the intrinsic and extrinsic loads that litter carries, also too are memory effects, i.e., the previous use of the item carries over its trace metal burden posing extreme risks to marine ecosystems. In the managing of risk associated with beach litter, legacy contaminants need be considered. • Toxic metal levels were determined in beach litter • Extreme concentrations were dependent on beach use • Extreme concentrations may be a result of "memory" effects i.e., the previous use of the item [ABSTRACT FROM AUTHOR]