Enhancing atrazine biodegradation by Pseudomonas sp. strain ADP adsorption to Layered Double Hydroxide bionanocomposites

To mimic the role of hydroxide minerals and their humic complex derivatives on the biodegradability of pesticides in soils, synthetic Mg(R)Al Layered Double Hydroxides (LDH) and Mg(R)Al modified by Humic substances (LDH-HA) were prepared for various R values (2, 3 and 4) and fully characterized. Adsorption properties of LDH and LDH-HA toward Pseudomonas sp. strain ADP were evaluated. The adsorption kinetics were very fast (<5 min to reach equilibrium). The adsorption capacities were greater than previously reported (13.5×10(11), 41×10(11) and 45.5×10(11) cells/gLDH for Mg(2)Al, Mg(3)Al and Mg(4)Al, respectively) and varied with both surface charge and textural properties. Surface modification by HA reduced the adsorption capacities of cells by 2-6-fold. Biodegradation kinetics of atrazine by Pseudomonas sp. adsorbed on both LDHs and LDH-HA complexes were measured for various solid/liquid ratios and adsorbed cell amounts. Biodegradation activity of bacterial cells was strongly boosted after adsorption on LDHs, the effect depending on the quantity and properties of the LDH matrix. The maximum biodegradation rate was obtained in the case of a 100 mg/mL Mg(2)Al LDH suspension (26 times higher than that obtained with cells alone).     

DNS analysis of partially premixed combustion in spray and gaseous turbulent flame-bases stabilized in hot air

Direct numerical simulations of weakly turbulent-lifted flame bases are examined in the case of both gaseous and spray fuel jet injection. Simplified transport properties and an adjustable single-step chemistry that matches the flame response to equivalence ratio are used. The flames are stabilized within a coflowing stream of heated air. The properties of the zone where burning starts are found to strongly depend on the type of fuel injection. The gaseous flame base is essentially composed of an edge flame, with a large contribution of partially premixed combustion. This partially premixed flame takes two different forms, a nearly stoichiometric propagating kernel and a rich trailing flame whose burning rate is diffusion controlled. The rich premixed flame is parallel to the stoichiometric line, along which a diffusion flame burns the fuel left by this rich trailing flame, up to the very leading edge of the flame base. In the spray case, a nonnegligible amount of oxidizer is entrained within the dilute spray, also leading to an important contribution of partially premixed burning. However, diffusion and premixed burning are found more distributed in space in the spray case than with gaseous injection. A progress variable that is generalized to partially premixed combustion is discussed and the relative contributions of the terms of its balance equation are analyzed from the DNS. A flame partitioning into premixed and diffusion types is then examined and the stabilization zone is decomposed into basic flame prototypes. A subgrid scale flame decomposition is further discussed from a direct filtering of DNS and some a priori tests of subgrid scale modeling are reported.     

Exhaustive test sets for algebraic specifications

In the context of testing from algebraic specifications, test cases are ground formulas chosen amongst the ground semantic consequences of the specification, according to some possible additional observability conditions. A test set is said to be exhaustive if every programme P passing all the tests is correct and if for every incorrect programme P, there exists a test case on which P fails. Because correctness can be proved by testing on such a test set, it is an appropriate basis for the selection of a test set of practical size. The largest candidate test set is the set of observable consequences of the specification. However, depending on the nature of specifications and programmes, this set is not necessarily exhaustive. In this paper, we study conditions to ensure the exhaustiveness property of this set for several algebraic formalisms (equational, conditional positive, quantifier free and with quantifiers) and several test hypotheses. Copyright © 2016 John Wiley & Sons, Ltd.     

Radon hazard in shallow groundwaters II: dry season fracture drainage and alluvial fan upwelling

²²²Rn concentrations have been measured in a well located on the edge of a large Pleistocene-Holocene fan and belonging to the shallow pyroclastic aquifer of the Pietramelara Plain, southern Italy. The aim of this study has been both to characterise the hydrological inputs that determine the influx of ²²²Rn to the shallow aquifer and to understand the correlations between ²²²Rn, major ions, physical-chemical parameters and rainfall. Results obtained from the time series indicate that the studied well shows a ²²²Rn variability that is inconsistent with a mechanism of pure hydrological amplification, such as described in Radon hazard in shallow groundwaters: Amplification and long term variability induced by rainfall (De Francesco et al., 2010a). On the contrary, in this well hydrological amplification appears to be mainly tied to the upwelling of alluvial fan waters, rich in radon, in response to pistoning from recharge in the carbonate substrate. This upwelling of alluvial fan waters occurs during almost the whole period of the annual recharge and is also responsible of the constant increase in ²²²Rn levels during the autumn-spring period, when both the water table level and weekly rainfall totals drop. Furthermore, a rapid delivery mechanism for ²²²Rn likely operates through fracture drainage in concomitance with the very first late summer-early autumn rains, when rainfall totals appear largely insufficient to saturate the soil storage capacity. Results obtained from this study appear to be particularly significant in both radon hazard zoning in relation to the shallow aquifer and possibly also for indoor radon, owing to possible shallow aquifer-soil-building exchanges. Moreover, both the spike-like events and the long wave monthly scale background fluctuations detected can also have potential significance in interpreting ²²²Rn time series data as seismic and/or volcanic precursors. Finally, ²²²Rn has proved to be an excellent tracer for hydrological inputs to the shallow aquifer when combined with major ions, physical-chemical data and geological and geomorphological controls.     

19号花园 伊尔玛夫人的花园

创造一个未来花园,就是任人们沉浸在时间的流逝中,任人们去幻想、影射、猜测、预计未来的脆弱性和各种可能发生的事情……就是与未来打一次赌。这个花园向我们推荐的旅程是在百里挑一的女主人——伊尔玛夫人的预言的引导下完成的,她会在家中接待您。参观者在色彩缤纷和充满符号的天地中探秘,被激起了无穷的好奇心。他在期待、疑虑、犹豫……     

Cleavage of desmin by cysteine proteases: Calpains and cathepsin B

The intermediate filament protein, desmin, was purified from pork longissimus dorsi and incubated with either μ-calpain, m-calpain or cathepsin B. Proteolysis of desmin was followed using SDS-PAGE and Western blotting. After incubation of desmin with the proteases, cleavage sites on the desmin molecule were identified by N-terminal sequencing of the different proteolytic fragments. Desmin incubated with either m-calpain or μ-calpain was primarily cleaved in the head and tail region leaving the rod domain relatively intact even after prolonged incubation. Incubation with cathepsin B produces a sequential C-terminal degradation pattern characteristic of this dipeptylpeptidase. The substrate primary structure was not found to be essential for regulation of the proteolytic activity of the cysteine peptidases studied. However, the degradation patterns obtained imply that calpains are involved in degradation of desmin early post-mortem, targeting the non-helical region of the desmin molecule and resulting in depolymerisation and initial disorganisation of the intermediate filament structures of the muscle cell.     

Fluorescence Polarization Immunoassay for Rapid, Accurate and Sensitive Determination of Ochratoxin A in Wheat

A sensitive and accurate fluorescence polarization (FP) immunoassay has been developed for the determination of ochratoxin A (OTA) in naturally contaminated wheat samples. A fluorescein-labeled OTA tracer was synthesized, and its binding response with three monoclonal antibodies was tested. The most sensitive competitive FP immunoassay showed an IC₅₀ value of 0.48 ng/mL with a negligible cross-reactivity for ochratoxin B (1.7 %) and no cross-reactivity with other mycotoxins commonly occurring in wheat. The wheat sample was extracted with acetonitrile/water (60:40, v/v) and purified by a rapid solid-phase extraction procedure using an aminopropyl column prior to the FP immunoassay. The overall time of analysis was less than 20 min. The average recovery from spiked wheat samples (3 to 10 μg/kg) was 87 %, with relative standard deviations generally lower than 6 %. Limits of detection and quantification were 0.8 and 2.0 μg/kg, respectively. The trueness of the method was assessed by using two reference materials for OTA showing good accuracy and precision. A good correlation (r?=?0.995) was observed between OTA contamination of 19 naturally contaminated wheat samples analyzed by both FP immunoassay and high-performance liquid chromatography/immunoaffinity clean-up used as reference method. These results show that the developed FP method is suitable for high-throughput screening, as well as for reliable quantitative determination of OTA in wheat at level far below the EU regulatory limits.     

Human factors systems approach to healthcare quality and patient safety

Human factors systems approaches are critical for improving healthcare quality and patient safety. The SEIPS (Systems Engineering Initiative for Patient Safety) model of work system and patient safety is a human factors systems approach that has been successfully applied in healthcare research and practice. Several research and practical applications of the SEIPS model are described. Important implications of the SEIPS model for healthcare system and process redesign are highlighted. Principles for redesigning healthcare systems using the SEIPS model are described. Balancing the work system and encouraging the active and adaptive role of workers are key principles for improving healthcare quality and patient safety.     

Skin Minerals: Key Roles of Inorganic Elements in Skin Physiological Functions

As odd as it may seem at first glance, minerals, it is what we are all about…or nearly. Although life on Earth is carbon-based, several other elements present in the planet’s crust are involved in and often indispensable for functioning of living organisms. Many ions are essential, and others show supportive and accessory qualities. They are operative in the skin, supporting specific processes related to the particular situation of this organ at the interface with the environment. Skin bioenergetics, redox balance, epidermal barrier function, and dermal remodeling are amongst crucial activities guided by or taking advantage of mineral elements. Skin regenerative processes and skin ageing can be positively impacted by adequate accessibility, distribution, and balance of inorganic ions.