3,215 research outputs found
Dispersants and Seafood Safety Assessment of the potential impact of Corexit® oil dispersants on seafood safety
The April 20, 2010 explosion and subsequent sinking of the Deepwater Horizon oil production platform (DWH) resulted in the largest oil spill in U.S. history. On April 29th, a Spill of National Significance was declared as roughly 53 thousand barrels of oil per day flowed into the Gulf of Mexico (GOM). The U.S. Coast Guard estimated 4.9 million barrels of crude oil escaped before the damaged DWH wellhead was sealed on July 15, 2010 (National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling 2010). Oil spill clean-up methods included skimming operations, burning of surface oil, siphoning oil into tankers directly from the wellhead, and the application of chemical dispersants. The first 3 methods mentioned above physically removed spilled oil from GOM waters. The last method, chemical dispersion, distributed insoluble fractions of the oil into the water-column. This was done for 3 reasons: 1) to reduce the exposure of response personnel at-sea to volatile organic compounds emanating from the surface slick; 2) to prevent concentrated surface oil from reaching, and damaging, fragile coastal wetlands, beaches and shoreline communities; and 3) to accelerate the break-down of spilled oil by natural microorganisms in the environment. The oil spill response contingency plan (RCP) applicable to the GOM (EPA Regions 4 and 6 within the National Response Plan framework) pre-authorized the use of Nalco Co. (Naperville, IL) oil dispersants Corexit® 9527 and Corexit® 9500 among other pre-approved product formulations. From April 22 to July 19, 2010 an estimated 1.1 million gallons of Corexit® dispersant were applied over approximately 300 square miles of oiled surface waters in the GOM and 771,000 gallons were injected directly into the oil free-flowing from the wellhead 5,100 feet beneath the surface (National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling 2010). Corexit® 9527 comprised approximately 215,000 gallons (~11%) of the total dispersant volume applied to the surface oil slick and was discontinued on May 22. The unprecedented volume of chemical dispersants used to combat the DWH oil spill elicited public concerns for the health of responders, coastal communities, marine life, and the safety of seafood from impacted areas of the GOM. This document will address the latter of these concerns
On the constrained KP hierarchy
An explanation for the so-called constrained hierarhies is presented by
linking them with the symmetries of the KP hierarchy. While the existence of
ordinary symmetries (belonging to the hierarchy) allows one to reduce the KP
hierarchy to the KdV hierarchies, the existence of additional symmetries allows
to reduce KP to the constrained KP.Comment: 7pp, LaTe
Cold atomic hydrogen in the inner galaxy
The VLA is used to measure 21 cm absorption in directions with the absolute value of b less than 1 deg., the absolute value of 1 less than 25 deg. to probe the cool atomic gas in the inner galaxy. Abundant H I absorption is detected; typical lines are deep and narrow, sometimes blending in velocity with adjacent features. Unlike 21 cm emission not all allowed velocities are covered: large portions of the l-v diagram are optically thin. Although not similar to H I emission, the absorption shows a striking correspondence with CO emission in the inner galaxy: essentially every strong feature detected in one survey is seen in the other. The provisional conclusion is that in the inner galaxy most cool atomic gas is associated with molecular cloud complexes. There are few or no cold atomic clouds devoid of molecules in the inner galaxy, although these are common in the outer galaxy
Christian Science and Religious Liberty
Prominent among the expressions of religious thought in this country in recent years is that of Christian Science. Its teaching in regard to the healing of disease without any material agencies has called forth many comments on the question of religious liberty. As it has attracted to it a large and ever increasing number of intelligent and law-abiding citizens, all over the country, and as there have been several efforts to partially or totally restrict its practice as a means of healing, by proscriptive legislation, we deem it proper to set forth, in a general way, some of the questions, with the conclusions of well recognized authorities, that lie at the root of the matter. While Christian Science is a healing system it cannot be considered as a school of medicine but only as a religious belief. It is defined by the Century Dictionary as a-system of religious teaching, based on the Scriptures, which originated with the Rev. Mary Baker Eddy about 1866. Its most notable application is in the professed cure of disease by mental and spiritual means
Pulse propagation in a hyper-lattice
The classical dynamics and pulse propagation are presented for a series of
lattice-like structures whose spatial dimensionality ranges from one to four:
four representing a hyper lattice. The lattices are connected one-dimensional
wave bearing systems of varying lengths and can illuminate some aspects of
higher dimension structures. Short pulses are launched at an arbitrary point,
reverberate throughout the entire structure, and detected at another point.
Some aspects of increasing dimensionality are illustrated with particular
emphasis on the transition from three to four spatial dimensions. In a
hypothetical four dimension world where only three are observable, the
classical conservation laws and causality do not hold. The lack of causality is
illustrated at each step in dimensionality by showing the unexpected pulse
returns from the next higher dimension
The correlation between far-IR and radio continuum emission from spiral galaxies
A sample of 30 galaxies selected for their intense IRAS flux at 60 and 100 micron using the Arecibo telescope at 21 cm to measure the continuum and HI line luminosities were observed. The centimeter wave continuum correlates very well with the far-infrared flux, with a correlation coefficient as high as that found for other samples, and the same ratio between FIR and radio luminosities. Weaker correlations are seen between the FIR and optical luminosity and between the FIR and radio continuum. There is very little correlation between the FIR and the HI mass deduced from the integral of the 21 cm line. The strength of the radio continuum correlation suggests that there is little contribution to either the radio and FIR from physical processes not affecting both. If they each reflect time integrals of the star formation rate then the time constants must be similar, or the star formation rate must change slowly in these galaxies
A primer on cointegration with an application to money and income
Money theory ; Income ; Cointegration
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