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Pool chemicals are utilized in pools to inactivate pathogens, optimize pH, and increase water clarity. This is conducted to ensure public health and safety by reducing bacteria concentrations and allowing distressed swimmers to be detected underwater. In commercial recreational facilities, muriatic acid and gaseous CO2 are typically used to maintain pH. Chlorine, which can take the form of liquid or solid tablets of sodium hypochlorite or granular calcium hypochlorite, is used to sanitize pool water, and is the most used chemical treatment in the world for swimming pools disinfection. If chlorine is mixed with muriatic acid, chlorine gas is formed, which can lead to severe injuries and fatalities (SIFs) to exposed individuals. This work illustrates an incident that occurred as a result of the simultaneous injection of muriatic acid and liquid sodium hypochlorite into a recreational natatorium chemical feed line. This led to the release of chlorine gas in the indoor environment, which resulted in injuries to five patrons. Furthermore, strategies are proposed to prevent this from occurring and to reduce the likelihood of similar incidents in the future. These include the implementation of fail-safe logic to prevent the controller from malfunctioning and ensuring that controller program settings do not permit simultaneous chemical injection.

Photodeposition of silver nanoparticles onto chemically patterned lithium niobate having alternating lithium niobate and proton exchanged regions has been previously investigated. Here, the spatially defined photodeposition of gold nanoparticles onto periodically proton exchanged lithium niobate is demonstrated. It is shown that the location where the gold nanoparticles form can be tailored by altering the concentration of HAuCl4. This enables the possibility to sequentially deposit gold and silver in different locations to create bimetallic arrays. The cytocompatibility of photodeposited gold, silver, and bimetallic ferroelectric templates to osteoblast-like cells is also investigated. Gold samples provide significantly greater cell biocompatibility than silver samples. These results highlight a potential route for using photodeposited gold on lithium niobate as a template for applications in cellular biosensing. Science Foundation Ireland Programme for Research in Third Level Institutions (PRTLI) Cycle 5 European Regional Development Fund Swedish Scientific Research Council ADOPT Linnaeus Centre for Advanced Optics and Photonics in Stockholm

Nano-bio interfaces play a significant role in assay device design and performance, here we study the use of a combined plasmonic and ferroelectric active substrate design for protein assemblies on ...

In this work, the influence of substrate surface charge on in vitro osteoblast cell proliferation on ferroelectric lithium niobate (LN) crystal surfaces is investigated. LN has a spontaneous polarization along the z-axis and is thus characterized by positive and negative bound polarization charge at the +z and -z surfaces. Biocompatibility of LN was demonstrated via culturing and fluorescence imaging of MC3T3 osteoblast cells for up to 11 days. The cells showed enhanced proliferation rates and improved osteoblast function through mineral formation on the positively and negatively charged LN surfaces compared to electrostatically neutral x-cut LN and a glass cover slip control. These results highlight the potential of LN as a template for investigating the role of charge on cellular processes.

We study Ag nanopattern arrays formed using ferroelectric lithography based on two separate approaches, i.e., periodically poled lithium niobate (PPLN) and periodically proton exchanged (PPE) template methods. We demonstrate that such nanoarrays are plasmon active. Raman spectroscopy was applied to study molecular probe 4-aminothiophenol (4-ABT) absorbed onto a silver nanostructured array. The observed Raman spectra show peaks arising from b2 modes, which occur for plasmon enhanced Raman from 4-ABT in place of a1 modes, which occur in normal Raman scattering. We demonstrate that the PPLN and PPE substrates possess different plasmonic properties with PPE creating a stronger SERS signal relative to PPLN substrates. Author has checked copyright 7/8/2013 SB.

Photodeposition of metallic nanostructures onto ferroelectric surfaces is typically based on patterning local surface reactivity via electric field poling. Here, we demonstrate metal deposition onto substrates which have been chemically patterned via proton exchange (i.e., without polarization reversal). The chemical patterning provides the ability to tailor the electrostatic fields near the surface of lithium niobate crystals and these engineered fields are used to fabricate metallic nanostructures. The effect of the proton exchange process on the piezoelectric and electrostatic properties of the surface is characterized using voltage modulated atomic force microscopy techniques, which combined with modeling of the electric fields at the surface of the crystal, reveal that the deposition occurs preferentially along the boundary between ferroelectric and proton exchanged regions. The metallic nanostructures have been further functionalized with a target probe molecule, 4-aminothiophenol, from which surface enhanced Raman scattering (SERS) signal is detected, demonstrating the suitability of chemically patterned ferroelectrics as SERS-active templates. Science Foundation Ireland Higher Education Authority This publication has emanated from research conducted with the financial support of the Higher Education Authority PRTLI-5 (DGPP and NANOREMEDIES), Science Foundation Ireland (SFI10/RFP/MTR2855), and UCD Research. This work was also supported by the Swedish Scientific Research Council (VR 622-2010-526 and 621-2011-4040) and the ADOPT Linné Center. The authors are grateful to COST actions MP0702 (STSM 8171) and MP0904. S.A.L. Weber acknowledges support from the Alexander von Humboldt Foundation. Author has checked copyright kpw26/3/13

The contribution of peroxisomal proliferator-activated receptor (PPAR)-γ agonism in pancreatic β-cells to the antidiabetic actions of thiazolidinediones has not been clearly elucidated. Genetic models of pancreatic β-cell PPARγ ablation have revealed a potential role for PPARγ in β-cell expansion in obesity but a limited role in normal β-cell physiology. Here we overexpressed PPARγ1 or PPARγ2 specifically in pancreatic β-cells of mice subjected to high-fat feeding using an associated adenovirus (β-PPARγ1-HFD and β-PPARγ2-HFD mice). We show β-cell-specific PPARγ1 or PPARγ2 overexpression in diet-induced obese mice exacerbated obesity-induced glucose intolerance with decreased β-cell mass, increased islet cell apoptosis, and decreased plasma insulin compared with obese control mice (β-eGFP-HFD mice). Analysis of islet lipid composition in β-PPARγ2-HFD mice revealed no significant changes in islet triglyceride content and an increase in only one of eight ceramide species measured. Interestingly β-PPARγ2-HFD islets had significantly lower levels of lysophosphatidylcholines, lipid species shown to enhance insulin secretion in β-cells. Gene expression profiling revealed increased expression of uncoupling protein 2 and genes involved in fatty acid transport and β-oxidation. In summary, transgenic overexpression of PPARγ in β-cells in diet-induced obesity negatively impacts whole-animal carbohydrate metabolism associated with altered islet lipid content, increased expression of β-oxidative genes, and reduced β-cell mass., Funding agencies:Canadian Diabetes Association University of Northern British Columbia Research Project Awards

We describe the results of a minisurvey of interstellar Ti II and Ca II absorption toward 42 early-type stars observed from the southern hemisphere at a spectral resolution of 4.5 km s-1. Results are also presented for the Na I ultraviolet line (3302 A) detected toward nine of these targets. We examine the dependence of the integrated column densities of N(Ti II), N(Ca II), and N(Na I) on distance, reddening, neutral hydrogen column density, and their Galactic elemental abundance. Our findings support the proposition that Ti II and Ca II absorption originates in the same regions of the pervasive, warm, and neutral intercloud gas of the interstellar medium. We have observed a correlation of decreasing Ti and Ca abundance with increasing line-of-sight gas density. The Ti II/Ca II abundance ratio has been found to be essentially constant under all the interstellar density conditions we have sampled. Thus, we conclude that the general absorption properties of titanium (and calcium) are similar throughout the entire disk of our Galaxy.

Local reactivity on periodically proton exchanged lithium niobate (PPE:LN) surfaces is a promising route for the fabrication of regularly spaced nanostructures. Here, using MgO-doped PPE:LN templates, we investigate the influence of the doping on the nanostructure formation as a function of the proton exchange (PE) depth. The deposition is found to occur preferentially along the boundary between MgO-doped LN and the PE region when the PE depth is at least 1.73 μm, however, for shallower depths, deposition occurs across the entire PE region. The results are found to be consistent with an increased photoconductivity of the MgO-doped LN. Science Foundation Ireland DGPP NANOREMEDIES Programme for Research in Third Level Institutions (PRTLI) Cycle 5 European Regional Development Fund Swedish Research Council UCD Research Author has checked copyright DOI link not active AS

Photoreduction on a periodically proton exchanged ferroelectric crystal leads to the formation of periodic metallic nanostructures on the surface. By varying the depth of the proton exchange (PE) from 0.59 to 3.10 µm in congruent lithium niobate crystals, the width of the lateral diffusion region formed by protons diffusing under the mask layer, can be controlled. The resulting deposition occurs in the PE region with the shallowest PE depth, and preferentially in the lateral diffusion region for greater PE depths. PE depth-control provides a route for the fabrication of complex metallic nanostructures with controlled dimensions on chemically patterned ferroelectric templates. Science Foundation Ireland This publication has emanated from research conducted with the financial support of the DGPP and NANOREMEDIES, which are funded under the Programme for Research in Third Level Institutions (PRTLI) Cycle 5 and co-funded by the European Regional Development Fund. We also acknowledge support from the Swedish Research Council (VR 622-2010-526 and 621-2011-4040). The AFM used for this work was funded by Science Foundation Ireland (SFI07/IN1/B931). Author has checked copyright TS 27.03.13

The preferential deposition of metal nanoparticles onto periodically poled lithium niobate surfaces, whereby photogenerated electrons accumulate in accordance with local electric fields and reduce metal ions from solution, is known to depend on the intensity and wavelength of the illumination and the concentration of the solution used. Here, it is shown that for identical deposition conditions (wavelength, intensity, concentration), post-poling annealing for 10 h at 200°C modifies the surface reactivity through the reorientation of internal defect fields. Whereas silver nanoparticles deposit preferentially on the +z domains on unannealed crystals, the deposition occurs preferentially along 180° domain walls for annealed crystals. In neither case is the deposition selective; limited deposition occurs also on the unannealed –z domain surface and on both annealed domain surfaces. The observed behavior is attributed to a relaxation of the poling-induced defect frustration mediated by Li+ ion mobility during annealing, which affects the accumulation of electrons, thereby changing the surface reactivity. The evolution of the defect field with temperature is corroborated using Raman spectroscopy. European Commission - Seventh Framework Programme (FP7) Higher Education Authority Swedish Scientific Research Council ADOPT Linnaeus Centre for Advanced Optics and Photonics, Stockholm Programme for Research in Third Level Institutions (PRTLI) Cycle 5 European Regional Development Fund

We have developed TiO2 coating on Ag-alloy sheathed Bi2Sr2CaCu2O8−x (Bi-2212) round-wire conductor for electrical insulation in Bi-2212 magnets. The green coating has a base layer comprised of TiO2, polyvinyl butyral (PVB) and a small amount of polysilicate and a top layer made of polyacrylic. The coating was applied on the conductor using a continuous reel-to-reel dip coating process and showed very good adherence and flexibility that is suitable for magnet coil winding. The thickness of the coating is a function of slurry viscosity, wire withdrawal speed and wire radius. Small test coils were built with the coated Bi-2212 round-wires and were heat treated at 100 atm pressure. During the heat treatment, the PVB and polyacrylic were removed from the green coating and the polysilicate decomposed to SiO2 that served as a sintering aid for TiO2. After the heat treatment, the coating remained strongly adhered to the conductor and did not have a detrimental effect on the critical current (Ic) values. The breakdown voltage was about 150 V across a 7 μm thick heat treated coating on Bi-22112 round-wire conductor, corresponding to a dc dielectric strength of about 21 MV m−1.

In modern Nb3Sn wires there is a fundamental compromise to be made between optimizing the intrinsic properties associated with the superfluid density in the A15 phase (e.g. Tc, Hc, Hc2, all of which are composition dependent), maximizing the quantity of A15 that can be formed from a given mixture of Nb, Sn and Cu, minimizing the A15 composition gradients within each sub-element, while at the same time generating a high vortex pinning critical current density, Jc, by maximizing the grain boundary density with the additional constraint of maintaining the RRR of the Cu stabilizer above 100. Here we study these factors in a Ta-alloyed Restacked-Rod-Process (RRP) wire with ~70 microns diameter sub-elements. Consistent with many earlier studies, maximum non-Cu Jc(12T,4.2K) requires preventing A15 grain growth, rather than by optimizing the superfluid density. In wires optimized for 12T, 4.2K performance, about 60% of the non-Cu cross-section is A15, 35% residual Cu and Sn core, and only 5% a residual Nb7.5wt.%Ta diffusion barrier. The specific heat and chemical analyses show that in this 60% A15 fraction there is a wide range of Tc and chemical composition that does diminish for higher heat treatment temperatures, which, however, are impractical because of the strong RRR degradation that occurs when only about 2% of the A15 reaction front breaches the diffusion barrier. As this kind of Nb3Sn conductor design is being developed for sub-elements 1/2 the present size, it is clear that better barriers are essential to allowing higher temperature reactions with better intrinsic A15 properties. We present here multiple and detailed intrinsic and extrinsic evaluations because we believe that only such broad and quantitative descriptions are capable of accurately tracking the limitations of individual conductor designs where optimization will always be a compromise between inherently conflicting goals, 25 pages, 19 figures

EUVE J2056-17.1 is one of the brightest sources in the First EUVE Source Catalog with 0.24 counts s-1 in the Deep Survey Lexan/B band. We present optical and EUV results that show this source is one of the most active late-type dwarfs. EUVE observed a large flare with energy in excess of 1035 ergs in its Lexan/B band. The quiescent optical spectrum of the source reveals strong hydrogen Balmer and Ca II H and K emission. A strong Li I 6707 A line is also present in the spectrum. We have estimated a Li abundance of log N(Li) = 2.5±0.4. The high Li abundance and the high flare activity favors an interpretation where the enhanced Li is sustained by spallation reactions.

RSV-bronchiolitis is the predominant cause of severe respiratory tract infection in the first year of live, especially in the first 6 months when maternally derived antibodies are present. In this study we analyzed the decay of maternally derived antibodies to RSV. Sera of 44 children, taken at 0, 3 and 6 months of age, born in the period of march to June, were tested. In a western blot antibodies of IgG subclasses (IgG1, 2, 3 and 4) against structural proteins of RSV (fusionprotein (F), glycoprotein (G), Nucleocapsid (N) and phosphoprotein (P) were tested. Direct neutralizing antibodies were tested in a microneutralisation assay. All Children had antibodies of the IgG class at birth. In the western blot IgG1 antibodies showed the same pattern as IgG total. IgG2 was less often detectable. IgG3 and for were only detectable in one serum each, both sera taken at 0 months. This is in good agreement with the usual ratios of IgG subclasses in blood. Probably the western blot is not sensitive enough to detect IgG3 and 4 because of competition with abundant IgG1. Direct neutralizing antibodies diminished quickly in the first 3 months; GMT at 0 months 1:300, At 3 months 1:35, at 6 months 1:18. calculated plasma half live of neutralizing titers 26 days. This finding correlates well with normal plasma half-lives of IgG antibodies.: Prince et al. (J. Virology; 1985:517-520) find in a mouse model That neutralizing titers of > 1:100 are necessary for protection against lower respiratory tract infection and a titer of > 1:380 for complete protection. The rapid fall of neutralizing titers in the first 3 months could be responsible for the fact that children are not protected against severe RSV infection.

High-resolution absorption measurements of the interstellar Na I D lines at 5890 A observed toward 27 early-type stars in the local interstellar medium (LISM) are presented. These results are combined with other high-resolution sodium measurements to map the space distribution of neutral sodium column density for some 118 stars out to less than 200 pc. These measurements indicate an upper limit to the neutral sodium column density of log N(Na I) less than 10.0/sq cm can be inferred out to a distance of 50 pc in most directions in the LISM. Also, the rarefield region of the Local Bubble may extend beyond 60 pc in at least 35 percent of the directions sampled thus far. Evidence is shown for a ubiquitous, comoving vector for neutral NaI gas clouds in the LISM which is in a different direction to LISM vectors previously reported for more ionized local gas clouds. A comparison of the measured sodium columns with those of interstellar Ca II for a sample of 12 stars within 95 pc results in a ratio of Na I/Ca II less than 0.5 for most stars. This value implies that there could be warm, neutral gas with T of about 12,500 K beyond 50 pc in the LISM.

In order to evaluate the benefit to be derived from the use of the E47 field protective mask drinking device, endurance in exhausting work in grade walking in a warm environment (46 C dry bulb, 23 C wet bulb) was measured before and after 6 hr of sweating. In nine men, the average dehydration was 4.3% of the body weight on the first day with restricted water intake, and 1.9% on a second day with unrestricted water intake by means of the drinking device. Endurance was reduced by 48% on the first day and by 22% on the second day. One canteen full of water would provide only a marginal benefit. Under these conditions, an intake of four canteens would be required to maintain optimal endurance. Exposure to heat and dehydration was accompanied by a hyperventilation that in four of the men exceeded 21 1/min. (Author)

The metabolism of rat retina was found to be sensitive to the concentration of the carbon dioxide-bicarbonate buffer system. Increasing the carbon dioxide from 1 per cent to 5 per cent at constant pH nearly doubled both respiration and glycolysis. Increasing the carbon dioxide at constant pH from 5 per cent to 20 per cent had no effect on glycolysis, but depressed the QOO2 from 31 to 19. In a medium containing glucose and the 1 per cent carbon dioxide-bicarbonate buffer, the addition of succinate increased the QOO2 from 12 to 26, without affecting glycolysis. In a medium containing glucose and phosphate, succinate had no significant effect.

REPEATED STUDY has shown that the blood iodine in hyperthyroid-ism tends to be abnormally high (Salter, 1944). Furthermore the “organic” or “hormonal” iodine accounts for most of the increase (Bassett, Coons and Salter, 1941). This finding suggests that the cir-culation contains an excess of a physiologically active iodine com-pound. It is the purpose of this communication to show that such blood can increase the respiration of surviving tissues. The time factor looms large in experimental attempts to demon-strate such stimulation of metabolism in vitro. Thus Davis and Has-tings (1936), using the heart of Limulus polyphemus, obtained an elevation of respiration only after 10 to 15 hours’ exposure to thyroxine in vitro. Hopping Scott (1935), however, reported in some instances a prompt increase in oxygen consumption by the nucleated red cells of alligator blood when thyroxine was added in vitro. In the present communication emphasis will be laid upon the prompt respiratory response of mammalian tissues (wh...

The objectives of the investigation were to find the intensities of work at which the reduction in endurance associated with inspiratory resistance would be the greatest and to test various hypotheses to account for the reduction. The following conclusions were reached: The reduction in endurance in exhausting work caused by an added inspiratory resistance is greater when the intensity is such that exhaustion is reached in from 5 to 15 minutes than when higher intensities of work lead to exhaustion in a shorter time; of the various factors examined in this report, the sense of impending exhaustion appears to be associated most closely with the reduction of the duration of expiration to a minimum value characteristic of the individual; in exhausting work, men can withstand the large elevation in alveolar carbon dioxide associated with the inhalation of carbon dioxide mixture better than the smaller but still substantial elevation in alveolar carbon dioxide associated with an added inspiratory resistance. (Author)

Manometric measurements were made of oxygen uptake (QOO2) and aerobic lactic acid output (QG) by slices of cerebral cortex and medulla oblongata of the cat in the presence of mixtures of 1, 5, and 20 volumes per cent of carbon dioxide in oxygen. The concentrations of NaHCO3 and NaCl in the medium were varied to maintain constant pH and sodium ion concentrations. The calcium ion concentration was 0.0002 M. At pH 7.5 under these conditions, an increase in carbon dioxide from 1 per cent to 5 per cent doubled the QG of both tissues but did not alter QOO2; an increase from 5 per cent to 20 per cent carbon dioxide had no further effect on QG in either tissue or QOO2 of cortex, but did depress the QOO2 of medulla. At pH 8.1, an increase in carbon dioxide from 1 per cent to 5 per cent raised the QOO2 and QG of cortex by about 60 per cent. Measurements at low oxygen tension carried out previously in phosphate medium were repeated in bicarbonate medium to obtain data for the combined output of lactic acid and carbon dioxide (QA). When the oxygen in the gas phase was decreased from 95 to 3 volumes per cent, the lactic acid output as measured colorimetrically increased by 114 mg./gm. in cortex and by 8 mg./gm. in medulla; QA increased from 12.3 to 13.5 in cortex and decreased from 5.1 to 3.8 in medulla.

Lactic acid production by rat retina in a medium containing phosphate was studied chemically. One half as much lactic acid was found as in a medium containing bicarbonate. In our experience the rate of respiration in a phosphate medium was sensitive to oxygen tension, for it was 38 per cent lower at 10 per cent and 51 per cent lower at 5 per cent oxygen than at 100 per cent oxygen. Previously Laser had reported no decrease in respiration at 5 per cent oxygen in phosphate medium. In phosphate medium, when the oxygen tension was varied, respiration and glycolysis bore a reciprocal relationship to each other. In bicarbonate medium, when the oxygen tension was lowered from 95 per cent to 5 per cent there was no significant change in the respiration, but glycolysis was increased nearly to the anaerobic level. This agrees with the earlier experiment of Laser in bicarbonate medium and adds support to his conclusion that the rate of glycolysis is controlled by oxygen tension rather than by the rate of respiration, under the conditions of the experiment.

The duration of maximum voluntary apnea (B) with fully inflated lungs in one experienced subject was determined during and immediately after treadmill exercise, with oxygen uptake (M) ranging up to...