3,075 research outputs found

    Putative Involvement of Adrenergic Receptors in Regulation of Mussel (Perna Canaliculus) Larval Settlement

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    Abstract: Settlement responses were investigated for mussel (Perna canaliculus) larvae after exposure to catecholamines and their precursor metabolites. Settlement and mortality assays were conducted in Petri plates with chemical treatments (L-phenylalanine, L-tyrosine, L-DOPA, dopamine hydrochloride and epinephrine at various concentrations) and controls. The proteinogenic amino acids L-phenylalanine and L-tyrosine were both effective inducers (~65%) of larval settlement at 10<sup>−5</sup> mol l<sup>−1</sup> compared with controls (4%). Exposure of larvae to L-DOPA, dopamine and epinephrine resulted in maximum settlement induction (50, 60 and 51%, respectively) at 10<sup>−5</sup> mol l<sup>−1</sup>. Larval mortalities were low (comparable to controls) across all concentrations of L-phenylalanine and L-tyrosine treatments, whereas high mortalities (>60%) were observed for L-DOPA, dopamine and epinephrine at concentrations ≥ 10<sup>−4</sup> mol l<sup>−1</sup>. Our results indicate that P. canaliculus larval settlement is under endogenous regulation by a catecholaminergic mechanism. Furthermore, the inductive effects of all tested metabolites in the epinephrine biosynthesis pathway point to a putative involvement of adrenergic-type receptors in the regulation of larval settlement in this mussel species

    Flexible and Robust Privacy-Preserving Implicit Authentication

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    Implicit authentication consists of a server authenticating a user based on the user's usage profile, instead of/in addition to relying on something the user explicitly knows (passwords, private keys, etc.). While implicit authentication makes identity theft by third parties more difficult, it requires the server to learn and store the user's usage profile. Recently, the first privacy-preserving implicit authentication system was presented, in which the server does not learn the user's profile. It uses an ad hoc two-party computation protocol to compare the user's fresh sampled features against an encrypted stored user's profile. The protocol requires storing the usage profile and comparing against it using two different cryptosystems, one of them order-preserving; furthermore, features must be numerical. We present here a simpler protocol based on set intersection that has the advantages of: i) requiring only one cryptosystem; ii) not leaking the relative order of fresh feature samples; iii) being able to deal with any type of features (numerical or non-numerical). Keywords: Privacy-preserving implicit authentication, privacy-preserving set intersection, implicit authentication, active authentication, transparent authentication, risk mitigation, data brokers.Comment: IFIP SEC 2015-Intl. Information Security and Privacy Conference, May 26-28, 2015, IFIP AICT, Springer, to appea

    Lean mass explains the association between muscular fitness and bone outcomes in 13-year-old boys

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    This is the author accepted manuscript. The final version is available from Wiley via the DOI in this record AIM: This study investigated the associations between fitness indices and bone outcomes in young males. METHODS: Data were collected between autumn and winter 2014-2015 on 121 males with a mean age of 13.1 ± 0.1 years: 41 swimmers, 37 footballers, 29 cyclists and 14 nonathletes. Participants were recruited from athletic clubs and schools across South West England. Lean mass, areal bone mineral density and hip structural estimates were measured using dual-energy X-ray absorptiometry. The relationships between bone outcomes and the vertical jump, standing long jump and the 20-m shuttle run test were analysed using three regression models: model 1 was adjusted by age and stature, model 2 added vigorous physical activity and model 3 then added lean mass. RESULTS: The boys' performance in the vertical jump and standing long jump was positively associated with the majority of bone outcomes in models 1 and 2, but most of these disappeared in model 3. The 20-m shuttle run test was positively associated with most bone outcomes in all three models. Lean mass played a key role in the association between muscular fitness and bone outcomes. CONCLUSION: Vigorous physical activity did not explain the associations between fitness and bone outcomes, but lean mass did.European Union Seventh Framework Programme (FP7/2007–2013

    L-selectin regulates human neutrophil transendothelial migration

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    The migration of circulating neutrophils towards damage/infected tissue is absolutely critical to the inflammatory response. L-selectin is a cell adhesion molecule abundantly expressed on circulating neutrophils. For over two decades, neutrophil L-selectin has been assigned the exclusive role of supporting tethering and rolling - the initial stages of the multi-step adhesion cascade. Here, we provide direct evidence for L-selectin contributing to neutrophil transendothelial migration (TEM). We show that L-selectin co-clusters with PECAM-1 - a well-characterised cell adhesion molecule involved in regulating neutrophil TEM. This co-clustering behaviour occurs specifically during TEM, which serves to augment ectodomain shedding of L-selectin and expedite the time taken for TEM (TTT) to complete. Blocking PECAM-1 signalling (through mutation of its cytoplasmic tail), PECAM-1-dependent adhesion, or L-selectin shedding, led to a significant delay in the TTT. Finally, we show that co-clustering of L-selectin with PECAM-1 occurs specifically across TNF-α- but not IL-1β-activated endothelial monolayers - implying unique adhesion interactomes forming in a cytokine-specific manner. To our knowledge, this is the first report to implicate a non-canonical role for L-selectin in regulating neutrophil TEM

    Kothe dual of Banach lattices generated by vector measures

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    We study the Kothe dual spaces of Banach function lattices generated by abstract methods having roots in the theory of interpolation spaces. We apply these results to Banach spaces of integrable functions with respect to Banach space valued countably additive vector measures. As an application we derive a description of the Banach dual of a large class of these spaces, including Orlicz spaces of integrable functions with respect to vector measuresThe first author was supported by the Foundation for Polish Science (FNP). The second author was supported by the Ministerio de Economia y Competitividad (Spain) under Grant #MTM2012-36740-C02-02.Mastylo, M.; Sánchez Pérez, EA. (2014). Kothe dual of Banach lattices generated by vector measures. Monatshefte fur Mathematik. 173(4):541-557. https://doi.org/10.1007/s00605-013-0560-8S5415571734Aronszajn, N., Gagliardo, E.: Interpolation spaces and interpolation methods. Ann. Mat. Pura. Appl. 68, 51–118 (1965)Bartle, R.G., Dunford, N., Schwartz, J.: Weak compactness and vector measures. Canad. J. Math. 7, 289–305 (1955)Brudnyi, Yu.A., Krugljak, N.Ya.: Interpolation functors and interpolation spaces II I . North-Holland, Amsterdam (1991)Curbera, G.P.: Operators into L1L^1 L 1 of a vector measure and applications to Banach lattices. Math. Ann. 293, 317–330 (1992)Curbera, G.P., Ricker, W.J.: The Fatou property in pp p -convex Banach lattices. J. Math. Anal. Appl. 328, 287–294 (2007)Delgado, O.: Banach function subspaces of L1L^1 L 1 of a vector measure and related Orlicz spaces. Indag. Math. 15(4), 485–495 (2004)Diestel, J., Jr., Uhl, J.J.: Vector measures, Amer. Math. Soc. Surveys 15, Providence, R.I. (1977)Fernández, A., Mayoral, F., Naranjo, F., Sánchez-Pérez, E.A.: Spaces of pp p -integrable functions with respect to a vector measure. Positivity 10, 1–16 (2006)Ferrando, I., Rodríguez, J.: The weak topology on LpL_p L p of a vector measure. Topol. Appl. 155, 1439–1444 (2008)Ferrando, I., Sánchez Pérez, E.A.: Tensor product representation of the (pre)dual of the LpL_p L p -space of a vector measure. J. Aust. Math. Soc. 87, 211–225 (2009)Galaz-Fontes, F.: The dual space of LpL^p L p of a vector measure. Positivity 14(4), 715–729 (2010)Kamińska, A.: Indices, convexity and concavity in Musielak-Orlicz spaces, dedicated to Julian Musielak. Funct. Approx. Comment. Math. 26, 67–84 (1998)Kantorovich, L.V., Akilov, G.P.: Functional analysis, 2nd edn. Pergamon Press, New York (1982)Krein, S.G., Petunin, Yu.I., Semenov, E.M.: Interpolation of linear operators. In: Translations of mathematical monographs, 54. American Mathematical Society, Providence, R.I., (1982)Lewis, D.R.: Integration with respect to vector measures. Pacific. J. Math. 33, 157–165 (1970)Lewis, D.R.: On integrability and summability in vector spaces. Ill. J. Math. 16, 583–599 (1973)Lindenstrauss, J., Tzafriri, L.: Classical Banach spaces II. Springer, Berlin (1979)Lozanovskii, G.Ya.: On some Banach lattices, (Russian). Sibirsk. Mat. Z. 10, 419–430 (1969)Musielak, J.: Orlicz spaces and modular spaces. In: Lecture Notes in Math. 1034, Springer-Verlag, Berlin (1983)Okada, S.: The dual space of L1(μ)L^1(\mu ) L 1 ( μ ) of a vector measure μ\mu μ . J. Math. Anal. Appl. 177, 583–599 (1993)Okada, S., Ricker, W.J., Sánchez Pérez, E.A.: Optimal domain and integral extension of operators acting in function spaces, operator theory. Adv. Appl., vol. 180, Birkhäuser, Basel (2008)Rao, M.M., Zen, Z.D.: Applications of Orlicz spaces. Marcel Dekker, Inc., New York (2002)Rivera, M.J.: Orlicz spaces of integrable functions with respect to vector-valued measures. Rocky Mt. J. Math. 38(2), 619–637 (2008)Sánchez Pérez, E.A.: Compactness arguments for spaces of pp p -integrable functions with respect to a vector measure and factorization of operators through Lebesgue-Bochner spaces. Ill. J. Math. 45(3), 907–923 (2001)Sánchez Pérez, E.A.: Vector measure duality and tensor product representation of LpL_p L p spaces of vector measures. Proc. Amer. Math. Soc. 132, 3319–3326 (2004)Zaanen, A.C.: Integration. North Holland, Amsterdam (1967

    A smog chamber comparison of a microfluidic derivatisation measurement of gas-phase glyoxal and methylglyoxal with other analytical techniques

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    A microfluidic lab-on-a-chip derivatisation technique has been developed to measure part per billion (ppbV) mixing ratios of gaseous glyoxal (GLY) and methylglyoxal (MGLY), and the method is compared with other techniques in a smog chamber experiment. The method uses-(2, 3, 4, 5, 6-pentafluorobenzyl) hydroxylamine (PFBHA) as a derivatisation reagent and a microfabricated planar glass micro-reactor comprising an inlet, gas and fluid splitting and combining channels, mixing junctions, and a heated capillary reaction microchannel. The enhanced phase contact area-to-volume ratio and the high heat transfer rate in the micro-reactor resulted in a fast and highly efficient derivatisation reaction, generating an effluent stream ready for direct introduction to a gas chromatograph-mass spectrometer (GC-MS). A linear response for GLY was observed over a calibration range 0.7 to 400 ppbV, and for MGLY of 1.2 to 300 ppbV, when derivatised under optimal reaction conditions. The analytical performance shows good accuracy (6.6% for GLY and 7.5% for MGLY), suitable precision (<12.0%) with method detection limits (MDLs) of 75 pptV for GLY and 185 pptV for MGLY, with a time resolution of 30 min. These MDLs are below or close to typical concentrations of these compounds observed in ambient air. The feasibility of the technique was assessed by applying the methodology to quantify α-dicarbonyls formed during the photo-oxidation of isoprene in the EUPHORE chamber. Good correlations were found between microfluidic measurements and Fourier Transform InfraRed spectroscopy (FTIR) with a correlation coefficient (2) of 0.84, Broadband Cavity Enhanced Absorption Spectroscopy (BBCEAS) (2 Combining double low line 0.75), solid phase micro extraction (SPME) (2 Combining double low line 0.89), and a photochemical chamber box modelling calculation (2 Combining double low line 0.79) for GLY measurements. For MGLY measurements, the microfluidic technique showed good agreement with BBCEAS (2 Combining double low line 0.87), SPME (2 Combining double low line 0.76), and the modeling simulation (2 Combining double low line 0.83), FTIR (2 Combining double low line 0.72) but displayed a discrepancy with Proton-Transfer Reaction Time-of-Flight Mass Spectrometry (PTR-ToF-MS) with 2 value of 0.39

    Effects of external nutrient sources and extreme weather events on the nutrient budget of a Southern European coastal lagoon

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    The seasonal and annual nitrogen (N), phosphorus (P), and carbon (C) budgets of the mesotidal Ria Formosa lagoon, southern Portugal, were estimated to reveal the main inputs and outputs, the seasonal patterns, and how they may influence the ecological functioning of the system. The effects of extreme weather events such as long-lasting strong winds causing upwelling and strong rainfall were assessed. External nutrient inputs were quantified; ocean exchange was assessed in 24-h sampling campaigns, and final calculations were made using a hydrodynamic model of the lagoon. Rain and stream inputs were the main freshwater sources to the lagoon. However, wastewater treatment plant and groundwater discharges dominated nutrient input, together accounting for 98, 96, and 88 % of total C, N, and P input, respectively. Organic matter and nutrients were continuously exported to the ocean. This pattern was reversed following extreme events, such as strong winds in early summer that caused upwelling and after a period of heavy rainfall in late autumn. A principal component analysis (PCA) revealed that ammonium and organic N and C exchange were positively associated with temperature as opposed to pH and nitrate. These variables reflected mostly the benthic lagoon metabolism, whereas particulate P exchange was correlated to Chl a, indicating that this was more related to phytoplankton dynamics. The increase of stochastic events, as expected in climate change scenarios, may have strong effects on the ecological functioning of coastal lagoons, altering the C and nutrient budgets.Portuguese Science and Technology Foundation (FCT) [POCI/MAR/58427/2004, PPCDT/MAR/58427/2004]; Portuguese Science and Technology Foundation (FCT

    Dual function filtration and catalytic breakdown of organic pollutants in wastewater using ozonation with titania and alumina membranes

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    Water recycling via treatment from industrial and/or municipal waste sources is one of the key strategies for resolving water shortages worldwide. Polymer membranes are effective at improving the water quality essential for recycling, but depend on regular cleaning and replacement. Pure ceramic membranes can reduce the cleaning need and last significantly longer in the same applications while possessing the possibility of operating in more aggressive environments not suitable for polymers. In the current work, filtration using a tubular ceramic membrane (�-Al2O3 or TiO2) was combined with ozonation to remove organic compounds present in a secondary effluent to enhance key quality features of the water (colour and total organic carbon, TOC) for its potential reuse. ‘Bare’ commercial �-Al2O3 filters (pore size ∼0.58 �m) were tested as a microfiltration membrane and compared with the more advanced catalytically active TiO2 layer that was formed by the sol–gel method. The presence of anatase with a 4 nm pore size at the membrane surface was confirmed by X-ray diffraction (XRD) and N2 adsorption. Filtration of the effluent over a 2 h period led to a reduction in flux to 45% and 60% of the initial values for the �-alumina and TiO2 membrane, respectively. However, a brief dose (2 min) of ozone at the start of the run resulted in reductions to only 70% of the initial flux for both membranes. It is likely that the oxide’s functional property facilitated the formation of hydroxyl (OH•) or other radicals on the membrane surface from ozone decomposition which targeted the breakdown of organic foulants thus inhibiting their deposition. Interestingly, the porous structure therefore acted in a synergistic, dual function mode to physically separate the particulates while also catalytically breaking down organic matter. The system also greatly improved the efficiency of membrane filtration for the reduction of colour, A254 (organics absorption at the wavelength of 254 nm) and TOC. The best performance came from combined ozonation (2 min ozonation time with an estimated applied ozone dose of 8 mg L−1) with the TiO2 membrane, which was able to reduce colour by 88%, A254 by 75% and TOC by 43%. It is clearly evident that a synergistic effect occurs with the process combination of ozonation and ceramic membrane filtration demonstrating the practical benefit of combining ceramic membrane filtration with conventional water ozonation
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