Characterization of silver-kaolinite (AgK): an adsorbent for long-lived 129I species

Bentonite is a preferred buffer and backfill material for deep geological disposal of high-level nuclear waste (HLW). Bentonite does not retain anions by virtue of its negatively charged basal surface. Imparting anion retention ability to bentonite is important to enable the expansive clay to retain long-lived I-129 (iodine-129; half-life = 16 million years) species that may escape from the HLW geological repository. Silver-kaolinite (AgK) material is prepared as an additive to improve the iodide retention capacity of bentonite. The AgK is prepared by heating kaolinite-silver nitrate mix at 400 degrees C to study the kaolinite influence on the transition metal ion when reacting at its dehydroxylation temperature. Thermo gravimetric-Evolved Gas Detection analysis, X-ray diffraction analysis, X-ray photo electron spectroscopy and electron probe micro analysis indicated that silver occurs as AgO/Ag2O surface coating on thermally reacting kaolinite with silver nitrate at 400 degrees C

Formative Evaluation to Determine Facilitators and Barriers to Nurse-driven Implementation: Designing an Inpatient mHealth Intervention to Support Smoking Cessation

The inpatient setting is often a missed opportunity for the introduction of technology to promote health using behavioral techniques. Nurses are stakeholders in the implementation of technology for patients in the inpatient setting and are essential for the determination of feasibility and relevance. The objective of this study was to identify facilitators and barriers for introduction of health-related patient technology, and specifically the appropriateness of mobile health (mHealth) technology in the hospital setting as identified by nurse leaders and staff. Methods of formative evaluation included nurse leader and staff semi-structured interviews and qualitative analysis. Nurses are comfortable with patients using mHealth technology in the inpatient setting. Facilitators for the introduction of technology to hospitalized patients were identified. Based on the formative evaluation findings, we developed an Implementation Program for mHealth technology introduction in the inpatient setting

The hydrology of an ephemerally flooded doline: Pwll-y-Felin, South Wales, UK

The first annual hydrograph from an ephemerally-flooded doline in the UK is described. Flood duration and volume were characterised by combining water-level data with a detailed topographic survey. Rapid surface runoff of Na–SO4-type water is derived from a localized topographic catchment. The inflow stream produced a ‘flashy’ hydrograph with maximum flood depths reaching 7m when the doline can contain 7,383 m3 of water. Flooding occurred over 161 of the 365 day study period, with an average flood depth of 2.4m. Stage dependent drainage properties suggested that water loss is greater when the flood depth is >3m, indicating that there may be additional drainage conduits at higher levels within the doline. A conservative estimate of 138 ML year is provided for net loss of water to the underlying aquifer. The vegetation shows some zonation potentially related to flood duration, with higher diversity in the marginal zone subject to the greatest fluctuation in water levels. The classification of Pwll-y-Felin and other small ephemeral karstic water bodies should be considered not only as geological landforms but as small karstic dependant wetlands. Under-recording of small, isolated temporary water bodies is of concern to international conservation bodies. The methodology presented can help to characterize the hydrology of ephemerally flooded dolines and could be used better to understand karst dependent habitats, recharge in karst aquifers, water budget calculations and to improve management and regulation in karst aquifers

Adenine nucleotide-dependent regulation of assembly of bacterial tubulin-like FtsZ by a hypermorph of bacterial actin-like FtsA.

Cytokinesis in bacteria depends upon the contractile Z ring, which is composed of dynamic polymers of the tubulin homolog FtsZ as well as other membrane-associated proteins such as FtsA, a homolog of actin that is required for membrane attachment of the Z ring and its subsequent constriction. Here we show that a previously characterized hypermorphic mutant FtsA (FtsA*) partially disassembled FtsZ polymers in vitro. This effect was strictly dependent on ATP or ADP binding to FtsA* and occurred at substoichiometric levels relative to FtsZ, similar to cellular levels. Nucleotide-bound FtsA* did not affect FtsZ GTPase activity or the critical concentration for FtsZ assembly but was able to disassemble preformed FtsZ polymers, suggesting that FtsA* acts on FtsZ polymers. Microscopic examination of the inhibited FtsZ polymers revealed a transition from long, straight polymers and polymer bundles to mainly short, curved protofilaments. These results indicate that a bacterial actin, when activated by adenine nucleotides, can modify the length distribution of bacterial tubulin polymers, analogous to the effects of actin-depolymerizing factor/cofilin on F-actin

Modulation of the IgM gene expression and IgM immunoreactive cell distribution by the nutritional background in gilthead sea bream (Sparus aurata) challenged with Enteromyxum leei (Myxozoa)

The aim of the present work was to determine if a plant protein-based diet containing vegetable oils (VO) as the major lipid source could alter the distribution of IgM immunoreactive cells (IRCs) and the IgM expression pattern in the intestine and haematopoietic tissues of gilthead sea bream (GSB) (. Sparus aurata) challenged with the myxosporean Enteromyxum leei. In a first trial (T1), GSB fed for 9 months either a fish oil (FO) diet or a blend of VO at 66% of replacement (66VO diet) was challenged by exposure to parasite-contaminated water effluent. All fish were periodically and non-lethally sampled to know their infection status. After 102 days of exposure, samples of intestine and head kidney were obtained for IgM expression and immunohistochemical detection (IHC). Additional samples of spleen were taken for IHC. Fish were categorized as control (C, not exposed), and early (E), or late (L) infected. The 66VO diet had no effect on the number of IgM-IRCs in any of the tissues or on IgM expression in C fish, whereas the infection with E. leei had a strong effect on the intestine. A combined time-diet effect was also observed, since the highest expression and IRCs values were registered in the posterior intestine (Pi) of E-66VO fish. A positive correlation was found between IgM expression and the presence of IgM-IRCs in the Pi. The effect of the time of infection was studied more in detail in a second trial (T2) in which samples of Pi were taken at 0, 24, 51, 91 and 133 days after exposure to the parasite. A significant increase of the IgM expression was detected only in parasitized fish, and very late after exposure. These results show that the duration of the exposure to the parasite is the most determinant factor for the observed intestinal IgM increased phenotype which gets magnified by the feeding of a high VO-based diet. © 2012 Elsevier Ltd.This work was funded by EU through projects AQUAMAX (FOOD-CT-2006-16249; Sustainable Aquafeeds to Maximise the Health Benefits of Farmed Fish for Consumers) and ARRAINA (Advanced Research Initiatives for Nutrition & Aquaculture, FP7/2007/2013; grant agreement n° 288925), and by the Spanish Ministry of Science and Innovation (MICINN) through the project AGL2009-13282-C02-01. Additional funding was obtained from the “Generalitat Valenciana” (research grant PROMETEO 2010/006). I. E. received a Spanish PhD fellowship (FPI) from MICINN.Peer Reviewe

Anisotropic structural dynamics of monolayer crystals revealed by femtosecond surface x-ray scattering

X-ray scattering is one of the primary tools to determine crystallographic configuration with atomic accuracy. However, the measurement of ultrafast structural dynamics in monolayer crystals remains a long-standing challenge due to a significant reduction of diffraction volume and complexity of data analysis, prohibiting the application of ultrafast x-ray scattering to study nonequilibrium structural properties at the two-dimensional limit. Here, we demonstrate femtosecond surface x-ray diffraction in combination with crystallographic model-refinement calculations to quantify the ultrafast structural dynamics of monolayer WSe$_2$ crystals supported on a substrate. We found the absorbed optical photon energy is preferably coupled to the in-plane lattice vibrations within 2 picoseconds while the out-of-plane lattice vibration amplitude remains unchanged during the first 10 picoseconds. The model-assisted fitting suggests an asymmetric intralayer spacing change upon excitation. The observed nonequilibrium anisotropic structural dynamics in two-dimensional materials agrees with first-principles nonadiabatic modeling in both real and momentum space, marking the distinct structural dynamics of monolayer crystals from their bulk counterparts. The demonstrated methods unlock the benefit of surface sensitive x-ray scattering to quantitatively measure ultrafast structural dynamics in atomically thin materials and across interfaces