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State Water Resources Research Institute Program
The Anacostia River forms a 10 km tidal fresh-water estuary that is wholly within the boundaries of the District of Columbia. It is the major water body of the District. Unfortunately, this estuary is a distinctly unhealthy body of water especially as compared to the Potomac estuary that the Anacostia joins. In addition to a consumption advisory on fish, the bottom life of the Anacostia is highly depauperate (Cummins e.a. 1991). The clams and mussels and submerged aquatic vegetation (SAV) found in the nearby Potomac are missing in the Anacostia (Phelps 1985). Until now most of the problems of the bottom life in the Anacostia have been attributed to contaminants in the sediment (ICPRB 1991, 1992). However, evidence suggests problems may also come from toxic water conditions (Anoxia, toxic ammonia) developing in the Anacostia basin in late summer. This needs to be confirmed with continuous-recording probes. Determination of such major sources of toxicity in the Anacostia basin will enable effective decision-making to restore the benthic life. Development of a healthy clam population in the Anacostia could lead to SAV establishment through f
ClinicalTrials.gov - Information on Clinical Trials and Human Research Studies: Trial List
Cardiovascular Diseases; Cerebral Anoxia; Cerebrovascular Disorders; Defect, Congenital Heart; Heart Diseases; Transposition of Great Vessels; Heart Septal Defects, Ventricular
MedlinePlus
Medical Encyclopedia: Acute mountain sickness
High altitude cerebral edema; Altitude Anoxia; Altitude sickness; Mountain sickness; High altitude pulmonary edema
brain anoxia
brain Anoxia
Glyceraldehyde-3-Phosphate Dehydrogenase Mediates Anoxia Response and Survival in Caenorhabditis elegans
To assay for Anoxia-induced tissue damage, the wild-type and daf-2(e1370) adult animals were exposed to prolonged Anoxia or high-temperature Anoxia and examined using DIC Nomarski microscopy. We focused our analysis on the tissue at the anterior head region of the nematode however the entire animal was evaluated. Figure 3 shows that the wild-type and daf-2(e1370) animals exposed to 1 day of Anoxia at 20 had no significant tissue damage in comparison to normoxic controls. However, the few wild-type animals that survived 3 days of Anoxia at 20 showed notable tissue damage (100%, n 6). Specifically, there was an increase in cavities in the tissue surrounding the pharynx, a loss of pharynx structure, and an overall bent morphology in the head region ( Figure 3 ). In comparison, most (77.8%, n 18) of the daf-2(e1370) animals exposed to 5 days of Anoxia at 20 did not accumulate such tissue damage ( Figure 3 ). To further characterize the morphological defects of wild-type animals that survive 3 days of Anoxia, we used strain PD4792(mIs11 IV) in which GFP is expressed in cytoplasmic pharyngeal muscle and nuclear gut (multi-construct array containing myo-2 GFP, pes-10 GFP, and gut GFP). Due to their large size, we evaluated gut cells in the few PD4792 animals that survived 3 days of Anoxia and determined that these cells had abnormalities that included cavities within the cells or cellular loss (data not shown). Both wild-type and daf-2(e1370) adult animals survived and had normal pharynx structure when exposed to 1 day of normoxia at 28 . However, the majority (83%, n 6) of the few wild-type animals that survived Anoxia at 28 showed extensive tissue damage, including multiple cavities, abnormal pharynx structure, and a bent head, whereas the majority (83.3%, n 12) of the daf-2(e1370) animals did not display such tissue abnormalities ( Figure 3 ). These data suggest that daf-2(e1370) animals have an altered physiologic state that either pre
Dephosphorylation of Cell Cycle–regulated Proteins Correlates with Anoxia-induced Suspended Animation in Caenorhabditis elegans
). We confirm that embryos, L2 larvae, L4 larvae, dauer larvae, and adult nematodes survive 24 h of Anoxia at a rate of 90 (Figure 2 ). To completely describe the Anoxia survival rate of nematodes at all stages of development and to determine if specific stages of development are less sensitive to Anoxia, we subjected embryonic and postembryonic nematodes to Anoxia for 24, 48, and 72 h. We determined that the L1 larvae and L3 larvae stages survive 24 h of Anoxia at a rate of 90 (Figure 2 ). With the exception of embryos, starved L1 larvae, and dauer larvae, the nematode capacity to survive 72 h of Anoxia decreased. Nematodes at the L3 larvae stage appear to be more sensitive, in comparison to other developmental stages, to 48 h of Anoxia. Embryos laid from adults have high survival rates in Anoxia. Embryos removed from an adult can survive 24 h of Anoxia, however, the ability to survive prolonged Anoxia decreased, suggesting that the treatment of embryos or developmental stage may influence Anoxia survival (our unpublished results). L1 larvae that were starved have a higher survival rate to Anoxia than L1 larvae that had been fed, which could be due to stage of larvae development or a link between metabolism and Anoxia survival. Our studies conclude that all developmental stages can survive 24 h of Anoxia; however, the ability to survive prolonged exposure to Anoxia is influenced by the stage of development or treatment of the nematode.
Energy Citations Database (ECD) - - Document #4161856
A survey is made of protection by procedures carried out before irradiation; an attempt is made to examine the logical processes which lay behind the various experiments, rather than the experimental data itself. It is suggested that there has been a tendency for research workers in this field to be divided into separate schools. One began with the demonstration >50 yr ago, that the response of human skin to x rays could be diminished by the application of pressure by means of a vacuum cup, and culminated in the discovery in 1950 that induction of Anoxia is an effective method of protecting rats against total-body irradiation. The second trend had its origin in the work of radiochemists in the 1930's that radiochemical reactions, which were brought about by the products of the radiolysis of water, could be modified by simple procedures such as dilution or addition of other solvents, and later discovery of similar effects in biological systems. The separation of these two trends has not been absolute, and other mechanisms of radioprotection have also been considered. The work of Bacq and the Liege School is considered in detail. The Anoxia hypothesis is often referred to in the literature of chemical protection, but there appears to be confusion as to its exact nature and limits. Two mechanisms had been suggested which related chemical protection to Anoxia: pharmacological effects in vivo, and simple chemical removal of oxygen in vitro. It has been postulated that some protective drugs produce partial Anoxia in vivo to explain many of the observed results, and it has appeared reasonable to suggest that all drugs, including those of the sulfhydryl group, act via Anoxia, at least as far as the protection of mammalian tissues is concerned. Careful examination of the arguments brought forward in support of the Anoxia hypothesis (as applied to mammalian tissues) shows that they are not as conclusive as they once appeared to be. The reversal of cysteine protection by oxyge
anoxia
Next Term: Anoxia neonatorum
Cerebral Hypoxia Information Page: National Institute of Neurological Disorders and Stroke (NINDS)
Synonym(s):
Hypoxia, Anoxia
Rhode Island DEM/Bay Assessment & Response Team - Hypoxia (Low Oxygen) and Anoxia (No Oxygen)
Many conditions contribute to hypoxia. Warm water (e.g., in the summer, in shallows, or near factory effluent) holds less oxygen than cold. Sheltered coves with weak winds and currents allow water to stratify, to form a persistent, low-oxygen band rather than to mix and refresh from top to bottom. In stagnant waters, hypoxia or Anoxia is a natural condition, but it was rare in the Bay until humans significantly altered it.
Water Quality Information Center: Role of Nitrogen and Phosphorus in Chesapeake Bay Anoxia
Water Quality Information Center: Role of Nitrogen and Phosphorus in Chesapeake Bay Anoxia
Energy Citations Database (ECD) - - Document #6932087
The isolated, arterially perfused rabbit interventricular septum was used to study the effects of Anoxia and ischemia on thallium (Tl-201) exchange.^Anoxia or ischemia was introduced for periods of 20, 40, or 60 minutes during either uptake or washout of Tl-201.^These interventions were followed by a reperfusion period.^Effluent samples were collected during washout experiments.^Anoxia lasting 20, 40, or 60 minutes during uptake resulted in a decrease in net Tl-201 uptake, which was promptly reversed upon reoxygenation.^Effluent washout curves demonstrated that an increased efflux of Tl-201 occurred during 20 and 40 minutes of Anoxia.^Surprisingly, comparison of the Tl loss due to Anoxia during uptake with the loss of Tl during washout was consistent with an increased influx of Tl-201 during the first 40 minutes of Anoxia.^Between 40 and 60 minutes of Anoxia, the increased efflux of Tl-201 was reversed and the increase in Tl-201 influx was absent.^Total ischemia for 20, 40, or 60 minutes during uptake was followed by continued accumulation of Tl-201 in 8 of 9 septa.^Total ischemia during washout was followed by an immediate rapid washout of Tl-201 before a new steady-rate was achieved.^The authors conclude that these results represent important differences from those reported previously using K-42.^Anoxia did not increase the influx of K-42 observed with Tl-201.^Also, 60 minutes of ischemia did not result in progressive loss of TL-201 as previously noted for K-42.^This implies there are different sensitivities and/ or mechanisms for Tl as compared to K uptake.
1988: Global Biogeochemical Cycles, 2(4), 427-444
Abstract : We examine the causes of Anoxia in regions such as
the Eastern Mediterranean, which have exchange over sills with adjacent
basins. Box models show that the concentration of the limiting nutrient
is the major determinant of deep oxygen levels. The most effective way
of increasing nutrient concentrations to the point where Anoxia occurs
is to change the flow pattern across the sills ventilating the basins.
With a sill exchange pattern such as that in the present Strait of Sicily,
it is difficult to obtain Anoxia in the Eastern Mediterranean without also
driving the Western Mediterranean to low oxygen and high nutrient levels.
Episodes of Anoxia in the Eastern Mediterranean are associated with a freshening
of surface waters. A reversal in flow directions, presumably resulting
from the observed freshening, will inevitably lead to Anoxia asociated
with increased sediment burial rates of the limiting nutrient and will
leave the Western Mediterranean largely unaffected, in keeping with the
observational evidence.
http://www.gfdl.noaa.gov/~gth/netscape/1988/jls8802.html
Abstract: We examine the causes of Anoxia in regions such as
the Eastern Mediterranean, which have exchange over sills with adjacent
basins. Box models show that the concentration of the limiting nutrient
is the major determinant of deep oxygen levels. The most effective way
of increasing nutrient concentrations to the point where Anoxia occurs
is to change the flow pattern across the sills ventilating the basins.
With a sill exchange pattern such as that in the present Strait of Sicily,
it is difficult to obtain Anoxia in the Eastern Mediterranean without also
driving the Western Mediterranean to low oxygen and high nutrient levels.
Episodes of Anoxia in the Eastern Mediterranean are associated with a freshening
of surface waters. A reversal in flow directions, presumably resulting
from the observed freshening, will inevitably lead to Anoxia asociated
with increased sediment burial rates of the limiting nutrient and will
leave the Western Mediterranean largely unaffected, in keeping with the
observational evidence.
ARS | Publication request: Wounding, Anoxia and Cold Induce Sugarbeet Sucrose Synthase Transcriptional Changes That Are Unrelated to Protein Expression and Activity
Technical Abstract: Wounding, Anoxia, and cold are often encountered during production and storage of sugarbeet (Beta vulgaris L.) root. The effect of these stresses on the expression of sucrose synthase, a key enzyme in sugarbeet root metabolism implicated in root growth, carbon partitioning and postharvest storage loss, however, is largely unknown. Transcript and protein levels for the two sucrose synthase genes expressed in sugarbeet root (SBSS1 and SBSS2) and sucrose synthase enzyme activity were determined after wounding, Anoxia or exposure to low temperature during 24 h and 7 d time course experiments. Transcript levels for both genes were altered several fold in injured, anoxic and cold-treated roots with SBSS1 transcript levels elevated in response to all three stresses, and SBSS2 transcript levels elevated in response to wounding, cold and short exposures (3 to 12 h) to anaerobic conditions, but reduced in roots exposed to anaerobic conditions for more than 24 h. SBSS1 and SBSS2 protein levels exhibited little change in stressed roots, even after 7 d. Enzyme activity was also relatively unchanged in stressed roots, except for small activity differences of 1 - 2 d duration that were unrelated to transcriptional changes. The disparity between transcript levels, protein abundance and enzyme activity indicate that SBSS1 and SBSS2 expression in response to wounding, Anoxia and cold is largely regulated by post-transcriptional mechanisms. The unresponsiveness of sucrose synthase protein levels or enzyme activity to wounding, Anoxia and cold questions the importance of this enzyme to stress responses in sugarbeet root.
Oxygen as a Supportive Therapy in Fetal Anoxia (1950)
Periodical: Apgar, Virginia. Oxygen as a Supportive Therapy in Fetal Anoxia. The Bulletin of the New York Academy of Medicine 26, (1950): 474-478. Article.
Pollutant Loading Capacity for the Black River, Chehalis River System, Washington
DO levels were below the State water quality regulatory criterion of 8.0 mg/ L in almost all locations during the study. The slow middle reach of the river showed stratified conditions, with Anoxia in some of the deepest pools. Based on model simulations, DO was found to still fall below the 8.0 mg/ L criterion in the entire mainstem under "natural" conditions, and eutrophication was identified as a potential problem in the middle reach. A TMDL was proposed for BOD and ammonia that would prevent significant degradation of DO in the Black River. To prevent eutrophic conditions in the Black River, a TMDL for total phosphorus was proposed that establishes a protective criterion of 0.05 mg/ L for the middle river during the dry low-flow season.
Water Quality, Hydrology, and Phosphorus Loading to Little St. Germain Lake, Wisconsin, with Special Emphasis on the Effects of Winter Aeration and Ground-Water Inputs
Water Quality, Hydrology, and Phosphorus Loading to Little St. Germain Lake, Wisconsin, with Special Emphasis on the Effects of Winter Aeration and Ground-Water Inputs
Statement of Robert Heath, Aug. 5, 2002
With apparent increases in phytoplankton abundance, it is tempting to reminisce about the causes of large regions of Anoxia observed during the 1960s and early 1970s.
The Cause(s) of Continued Hypolimnetic Anoxia in Long Lake, Washington, Following Advances Wastewater Treatment by the City of Spokane.
The purpose of this study was to determine the cause(s) of continued hypolimnetic Anoxia in Long Lake with AWT in operation. Biochemical oxygen demand, chemical oxyen demand (COD) and sediment oxygen demand (SOD) were determined. Sediment oxygen demand was measured under stationary and dynamic conditions with a Gilson Differential Respirometer. In addition, the areal hypolimnetic oxygen demand (AHOD) for all study years (1972-1981) was determined. Chlorophyll a concentrations, phytoplankton biovolume, primary productivity, and Secchi disk visibility were used as measures of phytoplankton standing crop.
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