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The health risks associated with manganese (Mn) in drinking water, and an improved understanding of Mn accumulation within, and subsequent release from, distribution systems, have increased the need for robust, sustainable treatment options to minimize Mn concentrations in finished water. Biofiltration is an established and effective method to remove Mn in groundwater however, Mn removal in surface water biofilters is an emerging treatment process that has not been extensively studied. Seasonal variations in water temperature can present an operational challenge for surface water biofilters which may see reduced Mn removal under colder conditions. This study examined the microbiomes of surface water biofilters at three utilities (ACWD WTP, WTP B, and WTP D) which all experienced similar seasonal fluctuations in influent water temperature. High Mn removal was observed at the ACWD WTP for much of the year, but Mn removal decreased with a concurrent decrease in the influent water temperature (58% ± 22%). In contrast, both WTP B and WTP D achieved year-round Mn removal (84% ± 5% and 93% ± 8% respectively). Marker gene (16S rRNA) sequencing analysis of the biofilter microbiomes identified a high abundance of Betaproteobacteria in WTP B and WTP D (37% ± 12% and 21% ± 3% respectively), but a low abundance of Betaproteobacteria in the ACWD WTP (2% ± 2%). The microbiomes of new bench-scale biofilters, in operation at the ACWD WTP, were also investigated. The abundance of Betaproteobacteria was significantly greater (p < 0.05) after the biofilters had acclimated than before acclimation, and differential abundance analysis identified 6 genera within the Betaproteobacteria class were enriched in the acclimated microbiome. Additionally, the acclimated biofilters were able to maintain high Mn removal performance (87% ± 10%) when the influent water temperature decreased to 10 °C or less. Further analysis of previously published studies found the abundance of Betaproteobacteria was also significantly greater (p < 0.001) in biofilters with sustained Mn removal than in biofilters which did not treat for Mn as a contaminant, despite differences in design scale, source water, and media type. Microbiome network analysis identified multiple co-occurrence relationships between Betaproteobacteria and Mn oxidizing bacteria in the WTP B and WTP D biofilters, suggesting indirect contributions by Betaproteobacteria to biological Mn oxidation. These co-occurrence relationships were not present in the full-scale ACWD WTP microbiome. Whether the role of Betaproteobacteria in biological Mn oxidation is direct, indirect, or a combination of both, they are consistently present at a high abundance in both groundwater and surface water biofilters with sustained Mn removal, and their absence may contribute to the seasonal fluctuations in Mn removal observed at the ACWD WTP. This new insight to Betaproteobacteria and their role in Mn biofiltration could contribute to water innovation and design that would improve the reliability of Mn removal.

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This study investigated treatment strategies which accelerated the acclimation of new Mn-removing biofilters to help utilities respond to changing Mn regulations, such as the recent introduction of a health-based maximum acceptable concentration and a reduction in the aesthetic objective for Mn in drinking water by Health Canada. Bench-scale filters of either GAC or anthracite media were fed with applied water containing Mn (17-61 µg/L) from a full-scale plant over 294 days. Treatment strategies included the addition of H2O2 (1 mg/L) and/or an increase in pH from 6.8 to 7.5 through the addition of NaOH. The potential physico-chemical and biological mechanisms responsible for accelerated biofilter acclimation under the various redox conditions were investigated through thermodynamic modelling, to predict homogeneous Mn oxide formation, and 16S rRNA gene amplicon sequencing, to characterize the microbial community within the filters. GAC filters treated with NaOH, and both H2O2 and NaOH, were the first to acclimate (< 20 µg/L Mn in filter effluent) after 59 and 63 days respectively, while the ambient GAC filter took almost 3 times as long to acclimate (168 days), and the anthracite filters which received the same chemically adjusted water took almost 4 times as long (226 and 251 days, respectively). The accelerated acclimation in the treated GAC filters was likely due to physico-chemical oxidation via three potential mechanisms: (1) homogeneous oxidation of dissolved Mn(II) to Mn(III)/Mn(IV) oxides and the subsequent removal of oxides from solution through adherence to the GAC surface, (2) adsorption of dissolved Mn(II) to GAC and subsequent homogeneous or biological oxidation, or (3) formation of colloidal Mn(III)/Mn(IV) oxides and subsequent adsorption of dissolved Mn(II) to the Mn colloids. In the untreated GAC filter and all anthracite filters, which did not benefit from improved redox conditions or an active surface, physico-chemical mechanisms alone were insufficient for consistent Mn removal to less than 20 µg/L. Acclimation in these filters was delayed until a microbiome enriched with bacteria capable of biological nitrification and Mn oxidation evolved within the filters. The acclimated microbiome was consistent between GAC and anthracite filters and was significantly different from the non-acclimated microbiome (p < 0.001) initially formed during the early operation of the filters. Interestingly, treatment with NaOH, and NaOH and H2O2, which accelerated physico-chemical oxidation in GAC filters, was observed to delay the development of biological oxidation in anthracite filters, and thus deferred acclimation. Although some filters took longer to acclimate than others, once acclimation was reached all filters had a similar microbiome and were able to consistently remove Mn to below 20 µg/L.

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Objective We estimated the incremental (extra) direct medical costs of a population-based cohort of newly diagnosed systemic lupus erythematosus (SLE) for five years before and after diagnosis, and the impact of sex and socioeconomic status (SES) on pre-index costs for SLE. Methods We identified all adults newly diagnosed with SLE over 2001-2010 in British Columbia, Canada, and obtained a sample of non-SLE individuals from the general population, matched on sex, age, and calendar-year of study entry. We captured costs for all outpatient encounters, hospitalisations, and dispensed medications each year. Using generalised linear models, we estimated incremental costs of SLE each year before/after diagnosis (difference in costs between SLE and non-SLE, controlling for covariates). Similar models were used to examine the impact of sex and SES on costs within SLE. Results We included 3632 newly diagnosed SLE (86% female, mean age 49.6 ± 15.9) and 18,060 non-SLE individuals. Over the five years leading up to diagnosis, per-person healthcare costs for SLE patients increased year-over-year by 35%, on average, with the biggest increases in the final two years by 39% and 97%, respectively. Per-person all-cause medical costs for SLE the year after diagnosis (Year + 1) averaged C$12,019 (2013 Canadian) with 58% from hospitalisations, 24% outpatient, and 18% from prescription medications; Year + 1 costs for non-SLE averaged C$2412. Following adjustment for age, sex, urban/rural residence, socioeconomic status, and prior year's comorbidity score, SLE was associated with significantly greater hospitalisation, outpatient, and medication costs than non-SLE in each year of study. Altogether, adjusted incremental costs of SLE rose from C$1131 per person in Year -5 (fifth year before diagnosis) to C$2015 (Year -2), C$3473 (Year -1) and C$6474 (Year + 1). In Years -2, -1 and +1, SLE patients in the lowest SES group had significantly greater costs than the highest SES. Unlike the non-SLE cohort, male patients with SLE had higher costs than females. Annual incremental costs of SLE males (vs. SLE females) rose from C$540 per person in Year -2, to C$1385 in Year -1, and C$2288 in Year + 1. Conclusion Even years before diagnosis, SLE patients incur significantly elevated direct medical costs compared with the age- and sex-matched general population, for hospitalisations, outpatient care, and medications.

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Deletion of the biosynthetic 4,6-dehydratase gene, jadT, present in the angucycline jadomycin dideoxysugar biosynthetic pathway, led to the isolation of a novel C12 glucosylated jadomycin. JadS was identified as the catalyst responsible for glucosylation due to a loss of production of the glucosylated natural product in a ΔjadSΔjadT deletion strain. This study demonstrates that a 2,6-dideoxy-l-sugar glycosyltransferase is able to transfer d-glucose, exemplifying remarkable substrate tolerance.

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INTRODUCTION: Recombinant factor VIII (rFVIII) products with extended half-lives have the potential to improve adherence and outcomes in haemophilia beyond the results obtained with conventional rFVIII products. AIM: In the absence of head-to-head comparisons, annualized bleed rates (ABRs) and weekly factor consumption with rFVIII Fc fusion protein (rFVIIIFc) and conventional rFVIII products were indirectly compared using studies of continuous prophylaxis. METHODS: A systematic literature review was conducted to identify studies of rFVIII products for comparison with rFVIIIFc in the continuous prophylactic treatment of previously treated adolescents and adults with moderate and severe haemophilia A. Mean ABRs were compared between rFVIIIFc and individual rFVIII studies and between rFVIIIFc and a pooled measure for rFVIII estimated by meta-analysis. Comparisons of factor consumption were based on mean or median weekly factor consumption. RESULTS: Results from seven studies of conventional rFVIII products (injections 2-4 times week-1 ) were compared with rFVIIIFc (injections 1.4-2.4 times week-1 ). The pooled mean ABR for rFVIII products was significantly higher compared with rFVIIIFc (difference = 2.0; P = 0.007). Compared with most rFVIII studies, the reported weekly factor consumption was lower with rFVIIIFc [mean differences = 15.5-21.8 IU kg-1 week-1 (17-26%); median differences = 12.7-29.8 IU kg-1 week-1 (16-37%)]. In one comparison, mean weekly factor consumption with rFVIII was significantly lower but mean ABR was significantly higher than rFVIIIFc. CONCLUSION: Prophylaxis with rFVIIIFc may be associated with improved bleeding rates and lower weekly factor consumption than more frequently injected rFVIII products. Relative to rFVIII products with similar bleeding rates, results indicate that rFVIIIFc is associated with reduced weekly factor consumption while requiring fewer prescribed injections.

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The overall purpose of this research was to investigate disinfection by-product (DBP) concentrations and formation potential in filter backwash water (FBWW) and evaluate at bench-scale the potential impact of untreated FBWW recycle on water quality in conventional drinking water treatment. Two chlorinated organic compound groups of DBPs currently regulated in North America were evaluated, specifically trihalomethanes (THMs) and haloacetic acids (HAAs). FBWW samples were collected from four conventional filtration water treatment plants (WTP) in Nova Scotia, Canada, in three separate sampling and plant audit campaigns. THM and HAA formation potential tests demonstrated that the particulate organic material contained within FBWW is available for reaction with chlorine to form DBPs. The results of the study found higher concentrations of TTHMs and HAA9s in FBWW samples from two of the plants that target a higher free chlorine residual in the wash water used to clean the filters (e.g., clearwell) compared to the other two plants that target a lower clear well free chlorine residual concentration. Bench-scale experiments showed that FBWW storage time and conditions can impact TTHM concentrations in these waste streams, suggesting that optimization opportunities exist to reduce TTHM concentrations in FBWW recycle streams prior to blending with raw water. However, mass balance calculations demonstrated that FBWW recycle practice by blending 10% untreated FBWW with raw water prior to coagulation did not impact DBP concentrations introduced to the rapid mix stage of a plant's treatment train.

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Equations are obtained for determining the Legendre polynomial expansion coefficients of the phase function from angular or angular-spatial integrals of the radiance measured either in water or at the surface.

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Plane-to-point transformations are used to develop a version of the Hydrolight computer program with which to compute the spatial dependence of the irradiance and the scalar irradiance of the light field away from an isotropic point source deep within a spatially uniform ocean. The transformations are also used to derive analytic approximations for determining the diffuse attenuation coefficient and the mean cosine of the radiance far from an isotropic point source. Approximations for determining the asymptotic diffuse attenuation coefficient from measurements at only two distances far from the source are derived and numerically tested with the modified version of the Hydrolight computer program. New spatial integrals of the outward irradiance are also derived that provide a different way for correlating the inherent optical properties of seawater.

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The design of integrating cavity absorption meters of general geometry is analyzed for cases in which the incident illumination of the cavity is spatially uniform and isotropic, such as the meter of Fry et al. [Appl. Opt. 31, 2055 (1992)]. The analysis by Kirk [Appl. Opt. 34, 4397 (1995)] for the probability of photon survival in a spherical meter is extended to general geometries. An estimate of the effect of the shape of the cavity on the estimated absorption coefficient is given.

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A method for determining the ocean-bottom optical albedo R(b) from in-water upward and downward irradiance measurements at a shallow site is presented, tested, and compared with a more familiar approach that requires additional measurements at a nearby deep-water site. Also presented are two new algorithms for estimating R(b) from measurements of the downward irradiance and vertically upward radiance. All methods performed well in numerical situations at depths at which the influence of the bottom on the light field was significant.

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An algorithm is described and evaluated for determining the absorption and backscattering coefficients a(z) and bb(z) from measurements of the nadir-viewing radiance Lu(z) and downward irradiance Ed(z). The method, derived from radiative transfer theory, is similar to a previously proposed one for Eu(z) and Ed(z)and both methods are demonstrated with numerical simulations and field data. Numerical simulations and a sensitivity analysis show that good estimates of a(z) and bb(z) can be obtained if the assumed scattering phase function is approximately correct. In an experiment in Long Island Sound, estimates of a(z) derived with these methods agreed well with those obtained from an in situ reflecting tube instrument.

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A method was developed for determining the spatial distribution of a source from downward and upward irradiance measurements at a single wavelength in seawater of known optical properties. The algorithm uses measurements at two depths located an arbitrary distance apart and solves two nonlinear equations for two parameters that fit a globally exponential or linear source shape. Complex spatially dependent source shapes can be estimated from an irradiance profile by piecing together estimates from neighboring measurement pairs. Numerical tests illustrate the sensitivity of the algorithm to depth, measurement spacing, chlorophyll concentration, sensor noise, and uncertainty in the a priori assumed inherent optical properties. The algorithm works well with widely spaced measurements, moderate sensor noise, and uncertainties in the optical properties regardless of whether the assumed and true profiles are the same shape.

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A method is evaluated for estimating the absorption coefficient a and the backscattering coefficient b(b) from measurements of the upward and downward irradiances E(u)(z) and E(d)(z). With this method, the reflectance ratio R(z) and the downward diffuse attenuation coefficient K(d)(z) obtained from E(u)(z) and E(d)(z) are used to estimate the inherent optical properties R(infinity) and K(infinity) that are the asymptotic values of R(z) and K(d)(z), respectively. For an assumed scattering phase function beta , there are unique correlations between the values of R(infinity) and K(infinity) and those of a and b(b) that can be derived from the radiative transfer equation. Good estimates of a and the Gordon parameter G = b(b)/(a + b(b)) can be obtained from R(infinity) and K(infinity) if the true scattering phase function is not greatly different from the assumed function. The method works best in deep, homogeneous waters, but can be applied to some cases of stratified waters. To improve performance in shallow waters where bottom effects are important, the deep- and shallow-measurement reflectance models also are developed.

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The Zaneveld-Wells algorithm for calculating N inherent optical expansion coefficients from N + 1 measured angle-integrated moments of the radiant light field is investigated. Because the algorithm is well conditioned but sensitive to errors in the spatial derivatives, different approximations for the spatial derivatives are considered. The effects of noise and sensor error on the performance of the algorithm have been evaluated analytically, and testing with randomly sampled simulated noise was performed to assess the stability and sensitivity of the algorithm. Results show that the algorithm is fairly insensitive to sensor noise, but neither using a higher-order finite-difference approximation for the derivatives nor reformulating the algorithm into an integral form was successful in overcoming the large errors observed.

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The mean upward-scattering coefficient of the downward-traveling photons and the mean downward-scattering coefficient of the upward-traveling photons are two factors needed for the two-stream approximation to the radiative-transfer equation. Numerical values of each shape factor just beneath the surface and at asymptotic depths give an indication of the range of values at intermediate depths in spatially uniform waters with no sources and are used to obtain an approximate depth-dependent model for each shape factor. The shape factors are computed for different surface-illumination conditions, wavelengths, and chlorophyll concentrations.

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We solve an inverse problem of ocean optics for estimating spatially dependent absorption and scattering coefficients and for determining sources such as fluorescence, bioluminescence, or Raman scattering. The solution requires in situ measurement of the downward and upward plane irradiances and scalar irradiances and a priori estimation of the angular shape of the volume scattering function. Both an explicit algorithm and an implicit one are developed from new two-stream radiative-transfer equations that utilize an asymptotic radiance approximation to close the set of equations. A comparison of numerical tests for the two algorithms is given.

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The local diffuse attenuation coefficients for monochromatic net irradiance and monochromatic scalar irradiance differ from the corresponding spatially averaged coefficients except when both equal an eigenvalue of the radiative transfer equation. Explicit equations to relate spatially averaged to local coefficients that may be useful when inferring self-consistency (i.e., closure) of optical properties are given.