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The 2014–2017 global coral bleaching event caused widespread coral mortality; however, its impact on the capacity for coral reefs to maintain calcium carbonate structures has not been determined. Here, we quantified remotely sensed maximum heat stress during the 2014–2017 bleaching event, census‐based net carbonate budgets from benthic imagery and fish survey data, and net reef calcification from salinity normalized seawater total alkalinity anomalies collected from 2017–2019 for 56 Pacific coral reef sites (Mariana Islands, Northwestern Hawaiian Islands, Pacific Remote Island Areas, and American Samoa). We incorporated the census‐based and chemistry‐based metrics to determine a calcification vulnerability index for each site to maintain calcium carbonate balance to provide accessible information to managers and policy makers. Most coral reef sites likely experienced ecologically severe (79%, n = 44) or significant (9%, n = 7) heat stress during the 2014–2017 coral bleaching event. Census‐based net carbonate budgets (mean ± 95% = 2.1 ± 0.6 kg CaCO3 m−2 yr−1) were positive for 77% of sites (n = 43), neutral for 16% of sites (n = 9), and negative for 7% of sites (n = 4). Chemistry‐based relative net reef calcification (mean ± 95% = 22 ± 10 μmol kg−1) was positive for 84% of sites (n = 47), neutral for 11% of sites (n = 6), and negative for 5% of sites (n = 3). The calcification vulnerability index suggested the Pacific Ocean reef sites surveyed were of minimal (68%, n = 38) to moderate (32%, n = 18) concern for maintaining calcium carbonate balance following the bleaching event. This suggests that many reefs maintained positive calcium carbonate balance, but that a large number of reefs may be approaching a potential threshold for maintaining their calcium carbonate balance under the climate crisis. [ABSTRACT FROM AUTHOR]

In this study, we demonstrated the first, to our knowledge, integrated continuous bioprocess (ICB) designed for the production of acid‐sensitive monoclonal antibodies, prone to aggregate at low pH, on pilot scale. A high cell density perfusion culture, stably maintained at 100 × 106 cells/ml, was integrated with the downstream process, consisting of a capture step with the recently developed Protein A ligand, ZCa; a solvent/detergent‐based virus inactivation; and two ion‐exchange chromatography steps. The use of a mild pH in the downstream process makes this ICB suitable for the purification of acid‐sensitive monoclonal antibodies. Integration and automation of the downstream process were achieved using the Orbit software, and the same equipment and control system were used in initial small‐scale trials and the pilot‐scale downstream process. High recovery yields of around 90% and a productivity close to 1 g purified antibody/L/day were achieved, with a stable glycosylation pattern and efficient removal of impurities, such as host cell proteins and DNA. Finally, negligible levels of antibody aggregates were detected owing to the mild conditions used throughout the process. The present work paves the way for future industrial‐scale integrated continuous biomanufacturing of all types of antibodies, regardless of acid stability. [ABSTRACT FROM AUTHOR]

Monoclonal antibodies and antibody fragments are increasingly important classes of biotherapeutics. However, these products are both challenging and expensive to manufacture. New process analytical technologies used to monitor these products during their manufacture are of significant interest. Deep UV Raman spectroscopy promises to provide the required specificity and accuracy, however instruments, have historically been large and complex. In this paper, a new deep UV Raman instrument is described using a solid‐state laser and a spatial heterodyne spectrometer. The instrument overcomes practical limitations of the technique and could readily be used for online measurement. A series of observations have been made of biopharmaceutical products, including immunoglobulin G and domain antibodies. Where high levels of both specificity and linearity when measuring samples of different concentration with a precision of better than 0.05 mg/mL has been demonstrated. [ABSTRACT FROM AUTHOR]

The hydrodynamics within small boreal lakes have rarely been studied, yet knowing whether turbulence at the air--water interface and in the water column scales with metrics developed elsewhere is essential for computing metabolism and fluxes of climate-forcing trace gases. We instrumented a humic, 4.7 ha, boreal lake with two meteorological stations, three thermistor arrays, an infrared (IR) camera to quantify surface divergence, obtained turbulence as dissipation rate of turbulent kinetic energy (ε) using an acoustic Doppler velocimeter and a temperature-gradient microstructure profiler, and conducted chamber measurements for short periods to obtain fluxes and gas transfer velocities (k). Near-surface ε varied from 10-8 to 10-6 m² s-3 for the 0-4 ms-1 winds and followed predictions from Monin-Obukhov similarity theory. The coefficient of eddy diffusivity in the mixed layer was up to 10-3 m² s-1 on the windiest afternoons, an order of magnitude less other afternoons, and near molecular at deeper depths. The upper thermocline upwelled when Lake numbers (LN) dropped below four facilitating vertical and horizontal exchange. k computed from a surface renewal model using ε agreed with values from chambers and surface divergence and increased linearly with wind speed. Diurnal thermoclines formed on sunny days when winds were < 3 m s-1, a condition that can lead to elevated near-surface ε and k. Results extend scaling approaches developed in the laboratory and for larger water bodies, illustrate turbulence and k are greater than expected in small wind-sheltered lakes, and provide new equations to quantify fluxes. [ABSTRACT FROM AUTHOR]

Coral reefs are facing intensifying stressors, largely due to global increases in seawater temperature and decreases in pH. However, there is extensive environmental variability within coral reef ecosystems, which can impact how organisms respond to global trends. We deployed spatial arrays of autonomous sensors across distinct shallow coral reef habitats to determine patterns of spatiotemporal variability in seawater physicochemical parameters. Temperature and pH were positively correlated over the course of a day due to solar heating and light‐driven metabolism. The mean temporal and spatial ranges of temperature and pH were positively correlated across all sites, with different regimes of variability observed in different reef types. Ultimately, depth was a reliable predictor of the average diel ranges in both seawater temperature and pH. These results demonstrate that there is widespread environmental variability on diel timescales within coral reefs related to water column depth, which needs to be included in assessments of how global change will locally affect reef ecosystems. [ABSTRACT FROM AUTHOR]

Anthropogenic environmental change has increased coral reef disturbance regimes in recent decades, altering the structure and function of many coral reefs globally. In this study, we used coral community survey data collected from 1996 to 2015 to evaluate reef-scale coral calcification capacity (CCC) dynamics with respect to recorded pulse disturbances for 121 reef sites in the Main Hawaiian Islands and Mo'orea (French Polynesia) in the Pacific and the Florida Keys Reef Tract and St. John (U.S. Virgin Islands) in the western Atlantic. CCC remained relatively high in the Main Hawaiian Islands in the absence of recorded widespread disturbances; declined and subsequently recovered in Mo'orea following a crown-ofthorns sea star outbreak, coral bleaching, and major cyclone; decreased and remained low following coral bleaching in the Florida Keys Reef Tract; and decreased following coral bleaching and disease in St. John. Individual coral taxa have variable calcification rates and susceptibility to disturbances because of their differing life-history strategies. As a result, temporal changes in CCC in this study were driven by shifts in both overall coral cover and coral community composition. Analysis of our results considering coral lifehistory strategies showed that weedy corals generally increased their contributions to CCC over time while the contribution of competitive corals decreased. Shifts in contributions by stress-tolerant and generalist corals to CCC were more variable across regions. The increasing frequency and intensity of disturbances under 21st century global change therefore has the potential to drive lower and more variable CCC because of the increasing dominance of weedy and some stress-tolerant corals. [ABSTRACT FROM AUTHOR]

Background: Patients with multiple organ failure (MOF) often receive large amounts of resuscitation fluid, making them at high risk of fluid overload (FO). Our main objective was to investigate if the ability to achieve a negative fluid balance during the first 3 continuous renal replacement therapy (CRRT) days was associated with mortality in children with MOF.Methods: Retrospective cohort study in a tertiary multidisciplinary academic paediatric hospital. The study included 63 patients (age 0-18 years) with 3 or more failing organs receiving CRRT due to acute kidney injury and/or fluid overload.Results: The median age was 4 months, and PICU mortality was 29%. Survivors had significantly lower degree of FO at CRRT initiation, (median 15% (Interquartile range 9-22)) than non-survivors (24% (17%-37%), P = 0.002). On PICU admission, PIM-3 score was significantly higher in non-survivors (P = 0.01), but at CRRT initiation there was no difference in PELOD-2 score (P = 0.98). Mortality in patients achieving a cumulative net negative fluid balance during the first 3 days after CRRT initiation was 12%, compared to 86% in those not achieving this (P < 0.0001). In multivariate analysis, the inability to achieve a net negative fluid balance during 3 days after CRRT initiation (P < 0.0001) and FO >20% at CRRT initiation (P = 0.0019) remained associated with mortality.Conclusion: Our results suggest that early fluid removal is associated with improved patient outcome in critically ill children receiving CRRT, and that prompt measures should be taken to prevent fluid overload in critical illness. These results need to be verified in further, prospective studies. [ABSTRACT FROM AUTHOR]

Coral reef community composition and ecosystem function may change in response to anthropogenic ocean acidification. However, the magnitude of acidification on reefs will be modified by natural spatial and temporal variability in seawater CO2 chemistry. Consequently, it is necessary to quantify the ecological, biogeochemical, and physical drivers of this natural variability before making robust predictions of future acidification on reefs. In this study, we measured temporal and spatial physiochemical variability on a reef flat in Kāne'ohe Bay, O'ahu, Hawai'i, using autonomous sensors at sites with contrasting benthic communities and by sampling surface seawater CO2 chemistry across the reef flat at different times of the day during June and November. Mean and diurnal temporal variability of seawater CO2 chemistry was more strongly influenced by depth gradients (~ 0.5–10 m) on the reef rather than benthic community composition. Spatial CO2 chemistry gradients across the reef flat reflected the cumulative influence from benthic metabolism, bathymetry, and hydrodynamics. Based on graphical assessment of total alkalinity–dissolved inorganic carbon data, reef metabolism in November was dominated by organic carbon cycling over inorganic carbon cycling, while these processes were closely balanced in June. Overall, this study highlights the strong influence of depth on reef seawater CO2 chemistry variability through its effects on benthic biomass to seawater volume ratio, seawater flow rates, and residence time. Thus, the natural complexity of ecosystems where a combination of ecological and physical factors influence reef chemistry must be considered when predicting ecosystem biogeochemical responses to future anthropogenic changes in seawater CO2 chemistry. [ABSTRACT FROM AUTHOR]

Human activities have led to widespread ecological decline; however, the severity of degradation is spatially heterogeneous due to some locations resisting, escaping, or rebounding from disturbances.We developed a framework for identifying oases within coral reef regions using long‐term monitoring data. We calculated standardised estimates of coral cover (z‐scores) to distinguish sites that deviated positively from regional means. We also used the coefficient of variation (CV) of coral cover to quantify how oases varied temporally, and to distinguish among types of oases. We estimated "coral calcification capacity" (CCC), a measure of the coral community's ability to produce calcium carbonate structures and tested for an association between this metric and z‐scores of coral cover.We illustrated our z‐score approach within a modelling framework by extracting z‐scores and CVs from simulated data based on four generalized trajectories of coral cover. We then applied the approach to time‐series data from long‐term reef monitoring programmes in four focal regions in the Pacific (the main Hawaiian Islands and Mo'orea, French Polynesia) and western Atlantic (the Florida Keys and St. John, US Virgin Islands). Among the 123 sites analysed, 38 had positive z‐scores for median coral cover and were categorised as oases.Synthesis and applications. Our framework provides ecosystem managers with a valuable tool for conservation by identifying "oases" within degraded areas. By evaluating trajectories of change in state (e.g., coral cover) among oases, our approach may help in identifying the mechanisms responsible for spatial variability in ecosystem condition. Increased mechanistic understanding can guide whether management of a particular location should emphasise protection, mitigation or restoration. Analysis of the empirical data suggest that the majority of our coral reef oases originated by either escaping or resisting disturbances, although some sites showed a high capacity for recovery, while others were candidates for restoration. Finally, our measure of reef condition (i.e., median z‐scores of coral cover) correlated positively with coral calcification capacity suggesting that our approach identified oases that are also exceptional for one critical component of ecological function. Our framework provides ecosystem managers with a valuable tool for conservation by identifying "oases" within degraded areas. By evaluating trajectories of change in state (e.g., coral cover) among oases, our approach may help in identifying the mechanisms responsible for spatial variability in ecosystem condition. Increased mechanistic understanding can guide whether management of a particular location should emphasise protection, mitigation or restoration. Analysis of the empirical data suggest that the majority of our coral reef oases originated by either escaping or resisting disturbances, although some sites showed a high capacity for recovery, while others were candidates for restoration. Finally, our measure of reef condition (i.e., median z‐scores of coral cover) correlated positively with coral calcification capacity suggesting that our approach identified oases that are also exceptional for one critical component of ecological function. [ABSTRACT FROM AUTHOR]

Understanding bacterioplankton community dynamics in coastal hypoxic environments is relevant to global biogeochemistry because coastal hypoxia is increasing worldwide. The temporal dynamics of bacterioplankton communities were analysed throughout the illuminated water column of Devil's Hole, Bermuda during the 6-week annual transition from a strongly stratified water column with suboxic and high- pCO2 bottom waters to a fully mixed and ventilated state during 2008. A suite of culture-independent methods provided a quantitative spatiotemporal characterization of bacterioplankton community changes, including both direct counts and rRNA gene sequencing. During stratification, the surface waters were dominated by the SAR11 clade of A lphaproteobacteria and the cyanobacterium S ynechococcus. In the suboxic bottom waters, cells from the order C hlorobiales prevailed, with gene sequences indicating members of the genera C hlorobium and P rosthecochloris - anoxygenic photoautotrophs that utilize sulfide as a source of electrons for photosynthesis. Transitional zones of hypoxia also exhibited elevated levels of methane- and sulfur-oxidizing bacteria relative to the overlying waters. The abundance of both T haumarcheota and E uryarcheota were elevated in the suboxic bottom waters (> 109 cells l−1). Following convective mixing, the entire water column returned to a community typical of oxygenated waters, with E uryarcheota only averaging 5% of cells, and C hlorobiales and T haumarcheota absent. [ABSTRACT FROM AUTHOR]

In this article, the use of external damping systems for vibration mitigation of railway bridge dynamics is studied. For a presented case study bridge, the performance of different tuned mass damper systems (TMDs) is studied. During train passage, the change in dynamic characteristics of the bridge may produce a significant detune to a passive TMD. Therefore, routines for a variable stiffness TMD using incremental frequency estimates are developed. Based on numerical simulations, the cumulative fatigue damage is calculated for different damper systems. Due to resonant behavior, the results are found to highly depend on the train speed. Based on an assumed probability density function for the train speed, fragility curves are produced to express the probability of fatigue failure as a function of the number of train passages. [ABSTRACT FROM AUTHOR]

Ocean acidification is a direct consequence of increasing atmospheric carbon dioxide concentrations and is expected to compromise the structure and function of coral reefs within this century. Research into the effects of ocean acidification on coral reefs has focused primarily on measuring and predicting changes in seawater carbon (C) chemistry and the biological and geochemical responses of reef organisms to such changes. To date, few ocean acidification studies have been designed to address conservation planning and management priorities. Here, we discuss how existing marine protected area design principles developed to address coral bleaching may be modified to address ocean acidification. We also identify five research priorities needed to incorporate ocean acidification into conservation planning and management: (1) establishing an ocean C chemistry baseline, (2) establishing ecological baselines, (3) determining species/habitat/community sensitivity to ocean acidification, (4) projecting changes in seawater carbonate chemistry, and (5) identifying potentially synergistic effects of multiple stressors. [ABSTRACT FROM AUTHOR]

There is little doubt that human activities such as burning of fossil fuels and land use practices have changed and will continue to change the cycling of carbon in the global coastal ocean. In the present study, two biogeochemical box models were used to investigate the consequences of increasing atmospheric CO2 and subsequent ocean acidification and increasing riverine transport of organic matter and nutrients arising from human activities on land on the global coastal ocean between the years 1700 and 2300. Numerical simulations show that the net flux of CO2 between coastal ocean surface water and the atmosphere is likely to change during this time from net evasion to net invasion owing to increasing atmospheric CO2, increasing net ecosystem production arising from increasing nutrient loading to this region, and decreasing net ecosystem calcification due to lower carbonate ion concentration and subsequent lower surface water saturation state with respect to carbonate minerals. Model calculations show that surface water saturation state with respect to calcite will decrease 73% by the year 2300 under a business-as-usual scenario, which in concert with increasing temperature will cause overall biogenic calcification rate to decrease by 90%. Dissolution of carbonate minerals increased by 267% throughout the model simulation. This increase was in part due to increased invasion of atmospheric C02, but mainly due to greater deposition and remineralization of land-derived and in situ produced organic matter in the sediments, producing CO2 that caused pore water pH and carbonate saturation state to decrease. This decrease, in turn, drove selective dissolution of metastable carbonate minerals. As a consequence, the relative carbonate composition of the sediments changed in favor of carbonate phases with lower solubility than that of an average 15 mol% magnesian calcite phase. Model projected changes in surface water carbonate saturation state agree well with observations from the Hawaiian Ocean Time series and the calculated air-sea CO2 exchange agrees well with a recent independent estimate of this flux derived from measurements from diverse coastal ecosystems scaled up to the global coastal ocean area. [ABSTRACT FROM AUTHOR]

The shallow-water ocean environment is of great importance in the context of global change and is heavily impacted by human activity. This study evaluates the effects of human activity on the CO2 exchange between the atmosphere and the surface water of shallow-water oceans. The evaluation is based on changes in net ecosystem metabolism, net ecosystem calcification, and atmospheric CO2 concentrations, as seen in a process-driven biogeochemical box model. Numerical simulations show that this air-sea interface has probably served as a net source of CO2 to the atmosphere for much of the past 300 years, but has recently switched, or will switch soon, to a net sink of CO2, because of rising atmospheric CO2 and increasing inorganic nutrient load. [ABSTRACT FROM AUTHOR]

The shallow-water ocean environment is of great importance in the context of global change and is heavily impacted by human activity. This study evaluates the effects of human activity on the CO2 exchange between the atmosphere and the surface water of shallow-water oceans. The evaluation is based on changes in net ecosystem metabolism, net ecosystem calcification, and atmospheric CO2 concentrations, as seen in a process-driven biogeochemical box model. Numerical simulations show that this air-sea interface has probably served as a net source of CO2 to the atmosphere for much of the past 300 years, but has recently switched, or will switch soon, to a net sink of CO2, because of rising atmospheric CO2 and increasing inorganic nutrient load. [ABSTRACT FROM AUTHOR]

The effect of different test models for sodium lauryl sulfate (SLS)-induced irritant contact dermatitis on epidermal Langerhans cells (LC) numbers was examined. Finn Chambers, 8 and 12 mm, containing 15 and 34 or 50 μl, respectively, of 1% aq, solution of SLS were applied to human forearm skin for 48 h as single or repeated application. The results showed a clear difference between the effects with the 2 chamber sizes. The effect of the 8-mm chambers could result in increased, unchanged or decreased LC numbers, while 12-mm chambers always produced a decrease. These results seem to explain, at least partly, the discrepant results reported from various laboratories. [ABSTRACT FROM AUTHOR]