Survey of Portable Oil Detection Methods

2014 ◽  
Vol 2014 (1) ◽  
pp. 299894 ◽  
Author(s):  
Mike Goldthorp* ◽  
Patrick Lambert ◽  
Carl Brown
Keyword(s):  
Water Column ◽  
Detection Methods ◽  
Relative Cost ◽  
Oil In Water ◽  
Primary Focus ◽  
A Site ◽  
Multiple Samples ◽  
Spilled Oil ◽  
Made In

When oil is spilled into the marine environment, it may be found on the water's surface, in the water column, in the sediment, or on the shoreline. When delineating the extent of contamination, it is important to be able to differentiate the spilled oil from other components that may appear to be oil. There are established methods for detecting oil-in-water, such as fluorometry, that allow in situ measurements to be made. In this study, we investigate both established methods and potential technological advancements that could provide a means for a site investigator to gather meaningful on-site information regarding the presence of oil. The primary focus will be usefulness to a shoreline application, but application to other types of samples is addressed. The degree to which an oil could be identified using these portable methods, such as the ability to differentiate petrogenic from biogenic oils, is also discussed. Method comparisons are discussed, with relevance to portability, selectivity, relative cost, and ability to process multiple samples.

scholarly journals Pathogenic properties of enterohepatic Helicobacter spp. isolated from rhesus macaques with intestinal adenocarcinoma

2014 ◽  
Vol 63 (7) ◽  
pp. 1004-1016 ◽  
Author(s):  
Kvin Lertpiriyapong ◽  
Laurence Handt ◽  
Yan Feng ◽  
Thomas W. Mitchell ◽  
Kenneth E. Lodge ◽  
...  
Keyword(s):  
Rhesus Monkey ◽  
Rhesus Macaques ◽  
Detection Methods ◽  
Pathogenic Potential ◽  
Rrna Sequencing ◽  
Similar Disease ◽  
T84 Cell Line ◽  
Made In

Considerable progress has been made in understanding the roles of Helicobacter pylori in inflammation and gastric cancer; however, far less is known about the roles of enterohepatic Helicobacter species (EHS) in carcinogenesis and their zoonotic or pathogenic potential. We determined the prevalence of EHS infection in a cohort of geriatric rhesus monkeys in which intestinal adenocarcinoma (IAC) is common and investigated the association between EHS infection and IAC. The cohort consisted of 36 animals, 14 of which (age 26–35 years) had IAC. Of the 36 rhesus, 35 (97 %) were positive for EHS using PCR or bacterial isolation from faeces, colonic or tumour tissues. Only a single rhesus, which had IAC, was negative for EHS by all detection methods. The EHS identified by 16S rRNA sequencing in this study were from three Helicobacter taxa: Helicobacter macacae (previously rhesus monkey taxon 1), Helicobacter sp. rhesus monkey taxon 2, previously described from strain MIT 99-5507, and Helicobacter sp. rhesus monkey taxon 4, related to Helicobacter fennelliae. Thirteen of 14 monkeys with IAC were positive for either H. macacae (7/13, 54 %), EHS rhesus monkey taxon 4 (4/13, 31 %) or a mixture of the two EHS (2/13, 15 %). These results indicate that EHS are prevalent among aged rhesus macaques with IAC. Using Helicobacter genus-specific florescent in situ hybridization, EHS were detected on the surface of colonic epithelia of infected monkeys. All Helicobacter isolates, including H. macacae, effectively adhered to, invaded, and significantly induced proinflammatory genes, including IL-8, IL-6, TNF-α and iNOS, while downregulating genes involved in the function of inflammasomes, particularly IL-1β, CASPASE-1, NRLP3, NLRP6 and NLRC4 in the human colonic T84 cell line (P<0.0001). These results suggest that EHS may represent an aetiological agent mediating diarrhoea, chronic inflammation, and possibly intestinal cancer in non-human primates, and may play a role in similar disease syndromes in humans. Downregulation of inflammasome function may represent an EHS strategy for long-term persistence in the host and play a role in inducing pathological changes in the host’s lower bowel.

scholarly journals Stabilizing Hydrographic Profiles with Minimal Change to the Water Masses

2017 ◽  
Vol 34 (9) ◽  
pp. 1935-1945 ◽  
Author(s):  
Paul M. Barker ◽  
Trevor J. McDougall
Keyword(s):  
Water Column ◽  
Water Mass ◽  
Minimal Change ◽  
Water Masses ◽  
Oceanographic Data ◽  
Made In

AbstractBoth observed and averaged oceanographic data often contain regions with density inversions. This paper presents two methods of stabilizing a water column. The first method is intended for use with observed data; it minimally adjusts Absolute Salinity while leaving the values of in situ temperature unchanged. The second method adjusts the values of both Absolute Salinity and Conservative Temperature, and these adjustments are made in such a way as to cause the least possible damage to the water-mass structure of the vertical cast.

Wing lengths of Clamorous Reed Warblers Acrocephalus stentoreus in Israel

Ring ◽  
2004 ◽  
Vol 26 (2) ◽  
pp. 89-92
Author(s):  
John Morgan
Keyword(s):  
Wing Length ◽  
First Year ◽  
Comparable Data ◽  
Reed Warbler ◽  
Data Set ◽  
Acrocephalus Scirpaceus ◽  
Different Seasons ◽  
A Site ◽  
Made In ◽  
New Discovery

Wing lengths of Clamorous Reed Warblers Acrocephalus stentoreus in Israel Wing length measurements taken from first-year, pre- and post-moulting (annual, complete) Clamorous Reed Warblers were recorded at a site in northern Israel. The resulting data set was examined using a time-series of residuals (CUSUM). Results from this analysis can explain the reported heterogeneity found in a comparable data set by Merom et al. (1999). Further observations made in their paper are rebutted: (1) an implied assumption that Reed Warbler (Acrocephalus scirpaceus) spring migration in Israel ends by 1 May is contrary to other publications; (2) the late autumn occurence in N Israel of longer-winged 1st cal. yr. Reed Warblers, unconvincingly explained as either delayed migration by larger individuals or post fledging feather growth, is most likely due to birds from different provenances origins moving at different seasons; (3) growth during adulthood in Reed Warbler is not a new discovery, though presented as such.

The Carbon:²³⁴Thorium ratios of sinking particles in the California Current Ecosystem 2: Examination of a thorium sorption, desorption, and particle transport model

2019 ◽  
Author(s):  
Michael Stukel ◽  
Thomas Kelly
Keyword(s):  
Organic Carbon ◽  
Water Column ◽  
Particulate Organic Carbon ◽  
Transport Model ◽  
California Current ◽  
In Situ Measurements ◽  
Power Law Distribution ◽  
Sinking Particles ◽  
Organic Carbon Concentration

Thorium-234 (234Th) is a powerful tracer of particle dynamics and the biological pump in the surface ocean; however, variability in carbon:thorium ratios of sinking particles adds substantial uncertainty to estimates of organic carbon export. We coupled a mechanistic thorium sorption and desorption model to a one-dimensional particle sinking model that uses realistic particle settling velocity spectra. The model generates estimates of 238U-234Th disequilibrium, particulate organic carbon concentration, and the C:234Th ratio of sinking particles, which are then compared to in situ measurements from quasi-Lagrangian studies conducted on six cruises in the California Current Ecosystem. Broad patterns observed in in situ measurements, including decreasing C:234Th ratios with depth and a strong correlation between sinking C:234Th and the ratio of vertically-integrated particulate organic carbon (POC) to vertically-integrated total water column 234Th, were accurately recovered by models assuming either a power law distribution of sinking speeds or a double log normal distribution of sinking speeds. Simulations suggested that the observed decrease in C:234Th with depth may be driven by preferential remineralization of carbon by particle-attached microbes. However, an alternate model structure featuring complete consumption and/or disaggregation of particles by mesozooplankton (e.g. no preferential remineralization of carbon) was also able to simulate decreasing C:234Th with depth (although the decrease was weaker), driven by 234Th adsorption onto slowly sinking particles. Model results also suggest that during bloom decays C:234Th ratios of sinking particles should be higher than expected (based on contemporaneous water column POC), because high settling velocities minimize carbon remineralization during sinking.

Late Woodland Period Settlement Patterns in the Piedmont Uplands of Pennsylvania: The Evidence from 36CH161

1994 ◽  
Vol 14 (3) ◽  
pp. 245-285
Author(s):  
Paul A. Raber
Keyword(s):  
Raw Materials ◽  
Late Woodland ◽  
Woodland Period ◽  
Late Woodland Period ◽  
Chester County ◽  
Non Local ◽  
Primary Focus ◽  
A Site ◽  
Local Materials ◽  
Early Late

Investigations at 36Ch161, a site in the Piedmont Uplands of Chester County, Pennsylvania, have revealed a series of early Late Woodland Period camps associated with the Minguannan Complex. The use of local quartz seems to have been a primary focus of settlement at the site. Quartz, which formed an overwhelming majority of the assemblage, was used in ways that contrast strongly with that of non-local materials like jasper, a minority component of the assemblage obtained from quarries in the Hardyston Formation. The selection of raw materials suggests restrictions on access to certain materials perhaps imposed by territorial constraints. The combined evidence of artifact assemblage and cultural features indicates that 36Ch161 was inhabited seasonally by small, mobile groups of non-horticulturalists, a reconstruction consistent with that of Custer and others regarding the economy of the Minguannan Complex and related cultures of the Piedmont Uplands.

scholarly journals Development of Fragility Curves for Piping and Slope Stability of River Levees

Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 738
Author(s):  
Nicola Rossi ◽  
Mario Bačić ◽  
Meho Saša Kovačević ◽  
Lovorka Librić
Keyword(s):  
Slope Stability ◽  
Fragility Curves ◽  
Safety Margin ◽  
Water Levels ◽  
Flood Event ◽  
Soil Parameters ◽  
Design Code ◽  
A Site ◽  
Insight Into

The design code Eurocode 7 relies on semi-probabilistic calculation procedures, through utilization of the soil parameters obtained by in situ and laboratory tests, or by the means of transformation models. To reach a prescribed safety margin, the inherent soil parameter variability is accounted for through the application of partial factors to either soil parameters directly or to the resistance. However, considering several sources of geotechnical uncertainty, including the inherent soil variability, measurement error and transformation uncertainty, full probabilistic analyses should be implemented to directly consider the site-specific variability. This paper presents the procedure of developing fragility curves for levee slope stability and piping as failure mechanisms that lead to larger breaches, where a direct influence of the flood event intensity on the probability of failure is calculated. A range of fragility curve sets is presented, considering the variability of levee material properties and varying durations of the flood event, thus providing crucial insight into the vulnerability of the levee exposed to rising water levels. The procedure is applied to the River Drava levee, a site which has shown a continuous trend of increased water levels in recent years.

scholarly journals Visual Appearance of Oil on the Sea

2021 ◽  
Vol 9 (1) ◽  
pp. 97
Author(s):  
Merv Fingas
Keyword(s):  
Water Surface ◽  
Oil Spills ◽  
Discharge Rate ◽  
Physical Explanation ◽  
Visual Appearance ◽  
Oil In Water ◽  
Other Information ◽  
Surface Discharges ◽  
Oil Emulsions ◽  
Spilled Oil

The visual appearance of oil spills at sea is often used as an indicator of spilled oil properties, state and slick thickness. These appearances and the oil properties that are associated with them are reviewed in this paper. The appearance of oil spills is an estimator of thickness of thin oil slicks, thinner than a rainbow sheen (<3 µm). Rainbow sheens have a strong physical explanation. Thicker oil slicks (e.g., >3 µm) are not correlated with a given oil appearance. At one time, the appearance of surface discharges from ships was thought to be correlated with discharge rate and vessel speed; however, this approach is now known to be incorrect. Oil on the sea can sometimes form water-in-oil emulsions, dependent on the properties of the oil, and these are often reddish in color. These can be detected visually, providing useful information on the state of the oil. Oil-in-water emulsions can be seen as a coffee-colored cloud below the water surface. Other information gleaned from the oil appearance includes coverage and distribution on the surface.

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