High concentrations of suspended particulate matter in coastal waters directly affect or govern numerous water column and benthic processes. The concentration of suspended sediments derived from ...bottom sediment resuspension or discharge of sediment-laden rivers is highly variable over a wide range of time and space scales. Although there has been considerable effort to use remotely sensed images to provide synoptic maps of suspended particulate matter, there are limited routine applications of this technology due in part to the low spatial resolution, long revisit period, or cost of most remotely sensed data. In contrast, near daily coverage of medium-resolution data is available from the Moderate-resolution Imaging Spectroradiometer (MODIS) Terra instrument without charge from several data distribution gateways. Equally important, several display and processing programs are available that operate on low cost computers.
The utility of MODIS 250 m data for analyzing complex coastal waters was examined in the Northern Gulf of Mexico. Using simple processing procedures, MODIS images were used to map the concentration of Total Suspended Matter (TSM). A robust linear relationship was established between band 1 (620–670 nm) MODIS Terra 250 m data and in situ measurements of TSM (
r
2=0.89;
n=52; MSE=4.74) acquired during six field campaigns. This study demonstrates that the moderately high resolution of MODIS 250 m data and the operating characteristics of the instrument provide data useful for examining the transport and fate of materials in coastal environments, particularly smaller bodies of water such as bays and estuaries.
Recounting Slough's timeless story of rise and fall during America's most tumultuous decades, historian Richard L. Miller brings to life this extraordinary figure.
Background Newborns have frequent infections and manifest impaired vaccine responses, motivating a search for neonatal vaccine adjuvants. Alum is a neonatal adjuvant but might confer a TH 2 bias. ...Toll-like receptor (TLR) agonists are candidate adjuvants, but human neonatal cord blood monocytes demonstrate impaired TH 1-polarizing responses to many TLR agonists caused by plasma adenosine acting through cyclic AMP. TLR8 agonists, including imidazoquinolines (IMQs), such as the small synthetic 3M-002, induce adult-level TNF from neonatal monocytes, but the scope and mechanisms of IMQ-induced activation of neonatal monocytes and monocyte-derived dendritic cells (MoDCs) have not been reported. Objective We sought to characterize IMQ-induced activation of neonatal monocytes and MoDCs. Methods Neonatal cord and adult peripheral blood monocytes and MoDCs were cultured in autologous plasma; levels of alum- and TLR agonist–induced cytokines and costimulatory molecules were measured. TLR8 and inflammasome function were assayed by using small interfering RNA and Western blotting/caspase-1 inhibitory peptide, respectively. The ontogeny of TLR8 agonist–induced cytokine responses was defined in rhesus macaque whole blood ex vivo. Results IMQs were more potent and effective than alum at inducing TNF and IL-1β from monocytes. 3M-002 induced robust TLR pathway transcriptome activation and TH 1-polarizing cytokine production in neonatal and adult monocytes and MoDCs, signaling through TLR8 in an adenosine/cyclic AMP–refractory manner. Newborn MoDCs displayed impaired LPS/ATP-induced caspase-1–mediated IL-1β production but robust 3M-002–induced caspase-1–mediated inflammasome activation independent of exogenous ATP. TLR8 IMQs induced robust TNF and IL-1β in whole blood of rhesus macaques at birth and infancy. Conclusions IMQ TLR8 agonists engage adenosine-refractory TLR8 and inflammasome pathways to induce robust monocyte and MoDC activation and represent promising neonatal adjuvants.
We investigated the use of ocean color remote sensing to measure the transport of dissolved organic carbon (DOC) by the Mississippi River to the Gulf of Mexico. From 2000 to 2005 we recorded surface ...measurements of DOC, colored dissolved organic matter (CDOM), salinity, and water-leaving radiances during five cruises to the Mississippi River Plume. These measurements were used to develop empirical relationships to derive DOC, CDOM, and salinity from monthly composites of SeaWiFS imagery collected from 1998 through 2005. We compared our remote sensing estimates of river flow and DOC transport with data collected by the United States Geological Survey (USGS) from 1998 through 2005. Our remote sensing estimates of river flow and DOC transport correlated well (
r
2
∼
0.70) with the USGS data. Our remote sensing estimates and USGS field data showed low variability in DOC concentrations in the river end-member (7–11%), and high seasonal variability in river flow (∼
50%). Therefore, changes in river flow control the variability in DOC transport, indicating that the remote sensing estimate of river flow is the most critical element of our DOC transport measurement. We concluded that it is possible to use this method to estimate DOC transport by other large rivers if there are data on the relationship between CDOM, DOC, and salinity in the river plume.
Suspended particulate matter (SPM) plays an important role in primary production, pollutant transport, and other biogeochemical processes in coastal marine environments. We present an empirical ...two‐band ocean color remote sensing reflectance algorithm (Rrs670/Rrs555) for SPM concentrations developed using field measurements obtained in coastal waters influenced by the Mississippi River in 2000, 2002, and 2004. The ratio algorithm was also found to be highly correlated to backscattering coefficient (bbp(555), r2 = 0.96), the backscattering ratio (bbp(555)/bp(555), r2 = 0.82) and the spectral backscattering slope (γ, r2 = 0.72) in March 2002, a period with large hydrographic variability in the study area. Strong correlations between water column bbp(555), SPM and nonalgal absorption anap(443) suggest the dominant influence of nonalgal particles on bbp. SeaWiFS derived SPM and γ distributions indicated event‐based variability linked to energetic disturbances such as frontal passages, resuspension, and river discharge that with bbp/bp could reveal refractive index and particle size characteristics in the coastal environment.
Newborns are prone to microbial infection and have poor memory responses to multiple antigens. We have previously shown that human neonatal blood monocytes exhibit impaired TNF-α responses to most ...known TLR agonists, including the pure TLR7 agonist imiquimod. Surprisingly, however, neonatal TNF-α responses to the imiquimod congener R-848 (TLR 7/8) were fully intact. We now show that TLR8 agonists, including R-848 (TLR7/8), the imidazoquinoline congeners 3M-003 (TLR7/8) and 3M-002 (TLR8), as well as single-stranded viral RNAs (TLR8) induced robust production of the Th1-polarizing cytokines TNF-α and IL-12 from neonatal antigen-presenting cells (APCs) that substantially exceeds responses induced by TLR-2, -4, or -7 (alone) agonists. TLR8 agonists also effectively induced up-regulation of the costimulatory molecule CD40 on neonatal and adult myeloid dendritic cells (DCs). The strong activity of TLR8 agonists correlates with their induction of p38 MAP kinase phosphorylation and with degradation of IκB-α in both neonatal and adult monocytes. We conclude that TLR8 agonists are uniquely efficacious in activating costimulatory responses in neonatal APCs and suggest that these agents are promising candidate adjuvants for enhancing immune responses in human newborns.
During the passage of a cold front in March 2002, bio-optical properties examined in coastal waters impacted by the Mississippi River indicated that westward advective flows and increasing river ...discharge containing high concentrations of nonalgal particles contributed significantly to surface optical variability. A comparison of seasonal data from three cruises indicated spectral models of absorption and scattering to be generally consistent with other coastal environments, while their parameterization in terms of chlorophyll (Chl) alpha concentration showed seasonal variability. The exponential slope of the colored dissolved organic matter (CDOM) averaged 0.0161+/-0.00054 nm(-1) and nonalgal absorption averaged 0.011 nm(-1) with deviations from general trends observed due to anomalous water properties. Although the phytoplankton specific absorption coefficients varied over a wide range 0.02 to 0.1 m2 (mg Chl)(-1) at 443 nm being higher in offshore surface waters, values of phytoplankton absorption spectra at the Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) wave bands were highly correlated to modeled values. Particulate scattering characteristics were similar to observations for other coastal waters, while backscattering ratios were on average lower in phytoplankton-dominated surface waters (0.011+/-0.003) and higher in low Chl near-bottom waters (0.0191+/-0.0045). Average percent differences in remote sensing reflectance Rrs derived from modeled and in-water radiometric measurements were highest in the blue wave bands (52%) and at locations with more stratified water columns. SeaWiFS estimates of Chl and CDOM absorption derived using regional empirical algorithms were highly correlated to in situ data.
Collectivists
know themselves better than individualists do, in that collectivists provide
more accurate self-predictions of future behavior in situations with moral or
altruistic overtones. In 3 ...studies, respondents from individualist cultures
overestimated the likelihood that they would act generously in situations
involving redistributing a reward (Study 1), donating money (Study 2), or
avoiding rude behavior (Study 3), whereas collectivists were, in general, more
accurate in their self-predictions. Both groups were roughly accurate in
predicting the behavior of their peers. Collectivists were more accurate in
their self-predictions than were individualists, even when both groups were
sampled from the same cultural group (Study 4). Discussion centers on culturally
specific motivations that may bias the accuracy of self-insight and social
insight.
The Orinoco River is the fourth largest in the world in terms of water discharge and organic carbon export to the ocean. River export of organic carbon is a key component of the carbon cycle and the ...global carbon budget. Here, we examined the seasonal transport of organic carbon by the Orinoco River into the eastern Caribbean using the conservative relationship of colored dissolved organic matter (CDOM) and dissolved organic carbon (DOC) in low salinity coastal waters influenced by river plumes. In situ measurements of CDOM absorption, DOC, and salinity were used to develop an empirical model for DOC concentration at the Orinoco River Plume. Satellite remote sensing reflectances were used with empirical models to determine DOC and Particulate organic carbon (POC) river transport. Our estimates of CDOM and DOC significantly correlated with in situ measurements and were within the expected ranges for the river. Total organic carbon transport by the Orinoco River during the period of 1998 to 2010 was 7.10 ×1012 g C y−1, from 5.29 × 1012 g C y−1 of DOC and 1.81 × 1012 g C y−1 of POC, representing ∼6% increase to previous published estimates. The variability in organic carbon transport responded to the seasonality in river flow more than to changes in organic carbon concentration in the river. Our results corroborate that is possible to estimate organic carbon transport using ocean color data at global scales. This is needed to reduce the uncertainties of land–ocean carbon fluxes.
Key Points
Our method shows we can measure organic carbon transport by rivers from satellite
Our analysis of Orinoco River carbon fluxes reveals increased DOC transports
Our approach shows we can measure river flow using remote sensing
For many coastal waters, total suspended matter (TSM) plays a major role in key biological, chemical and geological processes. Effective mapping and monitoring technologies for TSM are therefore ...needed to support research investigations and environmental assessment and management efforts. Although several investigators have demonstrated that TSM or suspended sediments can be successfully mapped using MODIS 250 m data for relatively large water bodies, MODIS 250 m data is of more limited use for smaller estuaries and bays or aquatic systems with complex shoreline geometry. To adequately examine TSM in the Albemarle-Pamlico Estuarine System (APES) of North Carolina, the large-scale synoptic view of MODIS and the higher spatial resolution of other sensors are required. MODIS, Landsat 7 ETM+ and FORMOSAT-2 remote sensing instrument (RSI) data were collected on 8 November, 24 November and 10 December, 2010. Using TSM images (mg/L) derived from MODIS 250 m band 1 (620–670 nm) data, Landsat 7 ETM+ 30 m band 3 (630–690 nm) and FORMOSAT-2 RSI 8 m band 3 (630−690 nm) atmospherically corrected images were calibrated to TSM for select areas of the APES. There was a significant linear relationship between both Landsat 7 ETM+ (r2 = 0.87, n = 599, P < 0.001) and FORMOSAT-2 RSI (r2 = 0.95, n = 583, P < 0.001) reflectance images and MODIS-derived TSM concentrations, thus providing consistent estimates of TSM at 250, 30 and 8 m pixel resolutions. This multi-sensor approach will support a broad range of investigations on the water quality of the APES and help guide sampling schemes of future field campaigns.
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