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Enterovirus D68 (EV-D68) was recognized as a respiratory virus in 1962 (1). In 2014, unprecedented large outbreaks of EV-D68 infections associated with severe respiratory illnesses occurred in children in the [...]

By November 2021, the coronavirus disease (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), had claimed >5 million lives worldwide, including >700,000 in the United States (1-3). [...]

We evaluated the magnitude and composition (in terms of salinity, [sup.223]Ra and [sup.224]Ra activity, and nutrient concentrations) of submarine groundwater discharge (SGD) fluxes at 11 sites on the Kona coast of Hawaii. Discharging groundwater was typically brackish to saline and had high Ra activity relative to ocean water and fresher, inland groundwater. Brackish SGD fluxes, estimated using a mass-balance approach based on excess coastal ocean [sup.224]Ra activity, ranged from 3 to 1300 L [m.sup.-1] of coastline [min.sup.-1]. Fluxes of the freshwater component of SGD, calculated based on salinity, ranged from 2 to 310 L [m.sup.-1] [min.sup.-1]. Nutrient fluxes into coastal waters from SGD varied by up to three orders of magnitude among sites. Nitrate + nitrite (N + N), phosphate, and silica concentrations showed strong, inverse linear correlations with salinity in coastal seawater and groundwater. These correlations were consistent with previous work that documented conservative mixing between fresh, high-nutrient groundwater and saline, low-nutrient seawater at a few coastal ocean sites. We extend this conservative relationship to more coastal ocean sites and to groundwater in the coastal aquifer. N + N concentrations in the fresh component of discharging groundwater were higher at sites near golf courses and those with a greater percentage of bare land within a 5-km radius, and silica concentrations in the fresh component of discharging groundwater were higher at sites with more bare land and lower population densities. However, neither urbanization nor agriculture was significantly correlated with groundwater nutrient concentrations on this relatively undeveloped coast. doi: 10.4319/lo.2010.55.3.1105

We analyzed a 9-yr record of ocean color data from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) together with a 4-yr record of satellite-derived sea surface temperature (SST) measurements to investigate potential mechanisms influencing nearshore phytoplankton variability in the Southern California Bight. We also compared in situ physicochemical conditions at four shoreline stations during a year with an extensive nearshore dinoflagellate red tide (2005) to those of the following year when there was no extended red tide (2006). SeaWiFS data indicated that in spring, chlorophyll a (Chl a) and nitrate (N[O.sup.-.sub.3]) were inversely correlated to SSTs, consistent with an upwelling-dominated system, but in summer Chl a and NO-3 were unrelated to SST. Summer dissolved inorganic nitrogen concentrations were not well correlated between alongshore sampling stations, but showed a significant effect of tide stage (low vs. high). Mean summer nearshore Chl a was positively, linearly related to rainfall in the previous winter. The relationship between summer Chl a and winter precipitation could be due either to direct freshwater inputs during the winter rainy season or to delayed input via groundwater discharge. A first-order analysis of nutrient delivery from both surface runoff and groundwater discharge showed that they could sustain summer blooms of up to 7540 and 1700 [km.sup.2], respectively--areas on the order of the study site. However, precipitation-induced physical changes to the nearshore water column cannot be conclusively ruled out as a potential causative mechanism.

A study was conducted to examine the diversity and composition of denitrifying bacteria that vary across environmental gradients in both nitrate and salinity within an unconfined beach aquifer. The findings suggest that diversity in these enzymes results from adaptation to a particular environment rather than just random microheterogeneity alone.