Ground-water conditions in Utah, spring of 2001

USGS Publications Warehouse

Burden, Carole B.; Sory, J.D.; Danner, M.R.; Fisher, M.J.; Haraden, Peter L.; Kenney, T.A.; Eacret, Robert J.; Downhour, Paul; Slaugh, B.A.; Swenson, R.L.; Howells, J.H.; Christiansen, H.K.

2001-01-01

This is the thirty-eighth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, provide data to enable interested parties to maintain awareness of changing ground-water conditions.This report, like the others in the series, contains information on well construction, ground-water withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of ground water. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing ground-water conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 2000. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights and Division of Water Resources.

Ground-water conditions in Utah, spring of 2003

USGS Publications Warehouse

Burden, Carole B.; Enright, Michael; Danner, M.R.; Fisher, M.J.; Haraden, Peter L.; Kenney, T.A.; Wilkowske, C.D.; Eacret, Robert J.; Downhour, Paul; Slaugh, B.A.; Swenson, R.L.; Howells, J.H.; Christiansen, H.K.

2003-01-01

This is the fortieth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, provide data to enable interested parties to maintain awareness of changing ground-water conditions.This report, like the others in the series, contains information on well construction, ground-water withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of ground water. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing ground-water conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 2002. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights and Division of Water Resources.

Ground-water conditions in Utah, spring of 2000

USGS Publications Warehouse

Burden, Carole B.; Sory, J.D.; Danner, M.R.; Johnson, K.K.; Kenny, T.A.; Brockner, S.J.; Eacret, Robert J.; Downhour, Paul; Slaugh, B.A.; Swenson, R.L.; Howells, J.H.; Christiansen, H.K.; Fisher, M.J.

2000-01-01

This is the thirty-seventh in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, provide data to enable interested parties to maintain awareness of changing ground-water conditions.This report, like the others in the series, contains information on well construction, ground-water withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of ground water. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing ground-water conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 1999. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Divisions of Water Rights and Water Resources.

Ground-water conditions in Utah, spring of 2004

USGS Publications Warehouse

Burden, Carole B.; Allen, David V.; Danner, M.R.; Walzem, Vince; Cillessen, J.L.; Kenney, T.A.; Wilkowske, C.D.; Eacret, Robert J.; Downhour, Paul; Slaugh, B.A.; Swenson, R.L.; Howells, J.H.; Christiansen, H.K.; Fisher, M.J.

2004-01-01

This is the forty-first in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, provide data to enable interested parties to maintain awareness of changing ground-water conditions.This report, like the others in the series, contains information on well construction, ground-water withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of ground water. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing ground-water conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 2003. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights and Division of Water Resources.

Ground-water conditions in Utah, spring of 1994

USGS Publications Warehouse

Allen, D.V.; Garrett, R.B.; Sory, J.D.; Burden, Carole B.; Danner, M.R.; Herbert, L.R.; Steiger, J.I.; ReMillard, M.D.; Slaugh, B.A.; Swenson, R.L.; Howells, J.H.; Christiansen, H.K.; Bagley, A.D.

1994-01-01

This is the thirty-first in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Division of Water Resources, provide data to enable interested parties to keep abreast of changing ground-water conditions.This report, like the others in the series, contains information on well construction, ground-water withdrawal from wells, water-level changes, related changes in precipitation and streamflow, and chemical quality of water. Supplementary data, such as maps showing water-level contours, are included in reports of this series only for those years or areas for which applicable data are available and are important to a discussion of changing ground-water conditions.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 1993. Water-level fluctuations and selected related data, however, are described from the spring of 1989 to the spring of 1994. Much of the data used in this report were collected by the U.S. Geological Survey in cooperation with the Divisions of Water Rights and Water Resources, Utah Department of Natural Resources.

Co-conditioning and dewatering of chemical sludge and waste activated sludge.

PubMed

Chang, G R; Liu, J C; Lee, D J

2001-03-01

The conditioning and dewatering behaviors of chemical and waste activated sludges from a tannery were studied. Capillary suction time (CST), specific resistance to filtration (SRF), and bound water content were used to evaluate the sludge dewatering behaviors. Zeta potentials were also measured. Experiments were conducted on each sludge conditioned and dewatered separately, and on the sludge mixed at various ratios. Results indicate that the chemical sludge was relatively difficult to be dewatered, even in the presence of polyelectrolyte. When the waste activated sludge was mixed with the chemical sludge at ratios of 1:1 and 2:1, respectively, the dewaterability of chemical sludge improved remarkably while the relatively better dewaterability of the waste activated sludge deteriorated only to a limited extent. As the mixing ratios became 4:1 and 8:1, the dewaterability of the mixed sludge was equal to that of the waste activated sludge. The optimal polyelectrolyte dosage for the mixed sludge was equal to or less than that of the waste activated sludge. It is proposed that the chemical sludges act as skeleton builders that reduce the compressibility of the mixed sludge whose dewaterability is enhanced. Bound water contents of sludge decreased at low polyelectrolyte dosage and were not significantly affected as polyelectrolyte dosage increased. Advantages and disadvantages of co-conditioning and dewatering chemical sludge and waste activated sludge were discussed.

Ground-water conditions in Utah, spring of 1998

USGS Publications Warehouse

Susong, David D.; Burden, Carole B.; Sory, J.D.; Eacret, Robert J.; Johnson, K.K.; Loving, B.L.; Brockner, S.J.; Danner, M.R.; Downhour, Paul; Slaugh, B.A.; Swenson, R.L.; Howells, J.H.; Christiansen, H.K.; Herbert, L.R.

1998-01-01

This is the thirty-fifth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources, provide data to enable interested parties to maintain awareness of changing ground-water conditions.This report, like the others in the series, contains information on well construction, ground-water withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of ground water. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing ground-water conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 1997. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Divisions of Water Rights and Water Resources.

Calcium regulates the cell-to-cell water flow pathway in maize roots during variable water conditions.

PubMed

Wu, Yan; Liu, Xiaofang; Wang, Weifeng; Zhang, Suiqi; Xu, Bingcheng

2012-09-01

Soil water shortages can decrease root hydraulic conductivity and affect Ca uptake and movement through the plant. In this study, the effects of extra Ca(2+) applied in nutrient solution on the hydraulic properties of the whole roots (Lp(r)) and cortical cells (Lp(cell)) of maize (Zea mays L.) subjected to variable water conditions were investigated. Under well-watered conditions, extra Ca(2+) significantly increased the root Ca content, total root length, and lateral root number; however, it reduced the root cortical cell volume, Lp(r), and Lp(cell). Hg(2+) inhibition experiments suggested that extra Ca(2+) could reduce the contribution of the cell-to-cell water flow pathway. Osmotic stress (10% PEG6000) significantly decreased the cortical cell volume, Lp(r), and Lp(cell) in the control plants, but smaller decreases were observed in the extra Ca(2+) plants. The Hg(2+) treatment reduced the Lp(r) larger in the extra Ca(2+) plants (74.6%) than in the control plants (53.2%), suggesting a higher contribution of the cell-to-cell pathway. The larger Hg(2+) inhibition of the Lp(cell) in the extra Ca(2+) roots (67.2%) when compared to the controls (56.4%) indicated that extra Ca(2+) can mitigate the inhibition of aquaporin expression and/or activity levels via osmotic stress. After 2 d of rehydration, the extra Ca(2+) helped the Lp(r) and Lp(cell) to recover almost completely, but these properties only partially recovered in the control plants. In conclusion, extra Ca(2+) may adjust the contribution of cell-to-cell pathway by regulating the expression and/or activity levels of AQPs according to water availability; this regulation may weaken negative effects and optimize water use. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Developing a state water plan: Ground-water conditions in Utah, spring of 1978

USGS Publications Warehouse

Gates, Joseph S.; Jibson, W.N.; Herbert, L.R.; Mower, R.W.; Razem, A.C.; Cordova, R.M.; Jensen, V.L.; ReMillard, M.D.; Emett, D.C.; Sumison, C.T.; Carroll, P.A.; DeGrand, M.J.; Sandberg, G.W.

1978-01-01

This report is the fifteenth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, prepared cooperatively by the U.S. Geological Survey and the Utah Division of Water Resources, provide data to enable interested parties to keep abreast of changing ground-water conditions.This report, like the others (see References, p. 13), contains information on well construction, ground-water withdrawals, water-level changes, and related changes in precipitation and streamflow. Supplementary data such as graphs showing chemical quality of water and maps showing water-table configuration are included in reports of this series only for those years or areas for which applicable data are available and are important to a discussion of changing ground-water conditions.This report includes individual discussions of selected major areas of ground-water withdrawal in the State for the calendar year 1977. Water-level fluctuations, however, are described for the period spring 1977 to spring 1978. Much of the data used in this report were collected by the U.S. Geological Survey in cooperation with the Division of Water Rights, Utah Department of Natural Resources.

Developing a state water plan: Ground-water conditions in Utah, spring of 1979

USGS Publications Warehouse

Price, Don; Jibson, W.N.; Contratto, P. Kay; Mower, R.W.; Steiger, Judy I.; Jensen, V.L.; ReMillard, M.D.; Emett, D.C.; Sumison, C.T.; Carroll, P.A.; Neff, L.J.; Sandberg, G.W.; Herbert, L.R.

1979-01-01

This report is the sixteenth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, prepared cooperatively by the U.S. Geological Survey and the Utah Division of Water Resources, provide data to enable interested parties to keep abreast of changing ground-water conditions.This report, like the others in the series, contains information on well construction, ground-water withdrawals, water-level changes, and related changes in precipitation and streamflow. Supplementary data such as graphs showing chemical quality of water and maps showing water-table configuration are included in reports of this series only for those years or areas for which applicable data are available and are important to a discussion of changing ground-water conditions.This report includes individual discussions of selected major areas of ground-water withdrawal in the State for the calendar year 1978. Water-level fluctuations, however, are described for the period spring 1978 to spring 1979. Much of the data used in this report were collected by the U.S. Geological Survey in cooperation with the Division of Water Rights, Utah Department of Natural Resources.

Ground-water conditions in Utah, spring of 2005

USGS Publications Warehouse

Burden, Carole B.; Allen, David V.; Danner, M.R.; Walzem, Vince; Cillessen, J.L.; Kenney, T.A.; Wilkowske, C.D.; Eacret, Robert J.; Downhour, Paul; Slaugh, B.A.; Swenson, R.L.; Howells, J.H.; Christiansen, H.K.; Fisher, M.J.

2005-01-01

This is the forty-second in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, provide data to enable inter­ested parties to maintain awareness of changing ground-water conditions.This report, like the others in the series, contains information on well construction, ground-water with­drawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of ground water. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing ground-water conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 2004. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights and Division of Water Resources. This report is available online at http://www.waterrights.utah.gov/techinfo/ wwwpub/gw2005.pdf and http://ut.water.usgs.gov/publications/GW2005.pdf.

Ground-water conditions in Utah, spring of 2007

USGS Publications Warehouse

Burden, Carole B.; Allen, David V.; Danner, M.R.; Enright, Michael; Cillessen, J.L.; Gerner, S.J.; Eacret, Robert J.; Downhour, Paul; Slaugh, Bradley A.; Swenson, Robert L.; Howells, James H.; Christiansen, Howard K.; Fisher, Martel J.

2007-01-01

This is the forty-fourth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing ground-water conditions.This report, like the others in the series, contains information on well construction, ground-water withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of ground water. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing ground-water conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 2006. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is available online at http://www.waterrights.utah. gov/ and http://ut.water.usgs.gov/newUTAH/GW2007.pdf.

Ground-water conditions in Utah, spring of 2006

USGS Publications Warehouse

Burden, Carole B.; Allen, David V.; Danner, M.R.; Walzem, Vince; Cillessen, J.L.; Downhour, Paul; Wilkowske, C.D.; Eacret, Robert J.; Wilberg, D.E.; Slaugh, B.A.; Swenson, R.L.; Howells, J.H.; Christiansen, H.K.; Fisher, M.J.

2006-01-01

This is the forty-third in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable inter­ested parties to maintain awareness of changing ground-water conditions.This report, like the others in the series, contains information on well construction, ground-water with­drawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of ground water. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing ground-water conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 2005. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is available online at http://www.waterrights.utah. gov/techinfo/wwwpub/gw2006.pdf and http://ut.water.usgs. gov/publications/GW2006.pdf.

Ground-water conditions in Utah, spring of 2008

USGS Publications Warehouse

Burden, Carole B.; Allen, David V.; Danner, M.R.; Fisher, Martel J.; Freeman, Michael L.; Downhour, Paul; Wilkowske, C.D.; Eacret, Robert J.; Enright, Michael; Swenson, Robert L.; Howells, James H.; Christiansen, Howard K.

2008-01-01

This is the forty-fifth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing ground-water conditions.This report, like the others in the series, contains information on well construction, ground-water withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of ground water. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing ground-water conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 2007. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is available online at http://www.waterrights.utah.gov/techinfo/ and http://ut.water.usgs.gov/publications/GW2008.pdf.

Ground-water conditions in Utah, spring of 2009

USGS Publications Warehouse

Burden, Carole B.; Allen, David V.; Rowland, Ryan C.; Fisher, Martel J.; Freeman, Michael L.; Downhour, Paul; Nielson, Ashley; Eacret, Robert J.; Myers, Andrew; Slaugh, Bradley A.; Swenson, Robert L.; Howells, James H.; Christiansen, Howard K.

2009-01-01

This is the forty-sixth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing ground-water conditions. This report, like the others in the series, contains information on well construction, ground-water withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of ground water. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing ground-water conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of ground-water development in the State for calendar year 2008. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is available online at http://www.waterrights. utah.gov/techinfo/ and http://ut.water.usgs.gov/publications/ GW2009.pdf.

Physical Conditioning through Water Exercises.

ERIC Educational Resources Information Center

Conrad, C. Carson

This document describes activities in an aquatic program designed for an individual in sound health. Instructions for performing each activity are given in step-by-step outline form. The activities are arranged under the following categories: standing water drills; pool-side standing drills; gutter holding drills; bobbing (various forms);…

Methyl t-Butyl Ether Mineralization in Surface-Water Sediment Microcosms under Denitrifying Conditions

USGS Publications Warehouse

Bradley, P.M.; Chapelle, F.H.; Landmeyer, J.E.

2001-01-01

Mineralization of [U-14C] methyl t-butyl ether (MTBE) to 14CO2 without accumulation of t-butyl alcohol (TBA) was observed in surface-water sediment microcosms under denitrifying conditions. Methanogenic activity and limited transformation of MTBE to TBA were observed in the absence of denitrification. Results indicate that bed sediment microorganisms can effectively degrade MTBE to nontoxic products under denitrifying conditions.

Compensatory Muscle Activation During Unstable Overhead Squat Using a Water-filled Training Tube.

PubMed

Glass, Stephen C; Albert, Robert W

2018-05-01

Glass, SC, and Albert, RW. Compensatory muscle activation during unstable overhead squat using a water-filled training tube. J Strength Cond Res 32(5): 1230-1237, 2018-The purpose of this study was to assess compensatory muscle activation of core and support muscle during an overhead squat using a water-filled training tube. Eleven experienced weightlifting (age = 20.10 ± 0.99, mass 89.17 ± 6.88 kg) men completed 3, 30-second trials of an overhead squat using an 11.4 kg tube that was partially filled with water. A central valve allowed 3 conditions of water movement: 50% open, 100% open, and a stable(S), closed valve condition. Subjects completed 8-10 repetitions within each condition. Electromyographic (EMG) electrodes were placed over the belly of the vastus lateralis, deltoid, rectus abdominus, and paraspinal muscles and recorded during concentric and eccentric (ECC) phases. Integrated EMG were computed and converted to percent maximal voluntary contraction (%MVC). Compensatory activation was assessed using the natural log of the coefficient of variation of %MVC across repetitions. A 1-way repeated-measures analysis of variance across (phase, condition) was used. Significant compensatory muscle activation was seen in the deltoid muscle during ECC (100% open = 3.60 ± 0.50 > stable LogCV = 3.06 ± 0.45). In addition, paraspinal muscle activity was also more variable during the ECC phase (50% open LogCv = 3.28 ± 0.26 > stable = 2.77 ± 0.67). We conclude that the water-filled training tube induces compensatory muscle activation in the deltoid and paraspinal muscles during the ECC phase of the overhead squat.

78 FR 27033 - Safety Zone; High Water Conditions; Illinois River

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-09

...-AA00 Safety Zone; High Water Conditions; Illinois River AGENCY: Coast Guard, DHS. ACTION: Temporary... current extreme high-water conditions. This safety zone is necessary to protect the general public, levee... dangerously high water conditions, the Coast Guard established a safety zone on the Illinois River from Mile...

Arsenic in ground-water under oxidizing conditions, south-west United States

USGS Publications Warehouse

Robertson, F.N.

1989-01-01

play a role in the occurrence of arsenic in ground-water. Under oxidizing conditions in Arizona, arsenic in ground-water appears to be controlled in part by sorption or desorption of HAsO4???2 on active ferric oxyhydroxide surfaces. ?? 1989 Sciences and Technology Letters.

Function and biotechnology of extremophilic enzymes in low water activity

PubMed Central

2012-01-01

Enzymes from extremophilic microorganisms usually catalyze chemical reactions in non-standard conditions. Such conditions promote aggregation, precipitation, and denaturation, reducing the activity of most non-extremophilic enzymes, frequently due to the absence of sufficient hydration. Some extremophilic enzymes maintain a tight hydration shell and remain active in solution even when liquid water is limiting, e.g. in the presence of high ionic concentrations, or at cold temperature when water is close to the freezing point. Extremophilic enzymes are able to compete for hydration via alterations especially to their surface through greater surface charges and increased molecular motion. These properties have enabled some extremophilic enzymes to function in the presence of non-aqueous organic solvents, with potential for design of useful catalysts. In this review, we summarize the current state of knowledge of extremophilic enzymes functioning in high salinity and cold temperatures, focusing on their strategy for function at low water activity. We discuss how the understanding of extremophilic enzyme function is leading to the design of a new generation of enzyme catalysts and their applications to biotechnology. PMID:22480329

Hydrologic conditions in Florida during Water Year 2008

USGS Publications Warehouse

Verdi, Richard J.; Holt, Sandra L.; Irvin, Ronald B.; Fulcher, David L.

2010-01-01

Record-high and record-low hydrologic conditions occurred during water year 2008 (October 1, 2007-September 30, 2008). Record-low levels were caused by a continuation of the 2007 water year drought conditions into the 2008 water year and persisting until summer rainfall. The gage at the Santa Fe River near Fort White site recorded record-low monthly mean discharges in October and November 2007. The previous records for this site were set in 1956 and 2002, respectively. Record-high conditions in northeast and northwest Florida were caused by the rainfall and runoff associated with Tropical Storm Fay. For example, St. Mary's River near Macclenny recorded a new record-high monthly mean discharge in August 2008. The previous record for this site was set in 1945. Lake Okeechobee in south Florida reached new minimum monthly mean lake levels since monitoring began in 1912 from October to March during the 2008 water year. Some wells throughout northwest and south Florida registered period-of-record lowest daily maximum water levels.

Relationship between Hydrodynamic Conditions and Water Quality in Landscape Water Body

NASA Astrophysics Data System (ADS)

Kang, Mengxin; Tian, Yimei; Zhang, Haiya; Wang, Dehong

2018-01-01

The urban landscape water usually lacks necessary water cycle and water speed is closed to zero, which easily lead to eutrophication in water system and deterioration of water quality. Therefore, understanding the impact of water circulation on the water quality is of great significance. With that significance, this research has been done to investigate the relationship between hydrodynamic conditions and water quality of urban landscape water based on adopted water quality indexes such as chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP) and nitrogen-ammonia (NH3-N). Moreover, MIKE 21 model is used to simulate the hydrodynamics and water quality under different cases in an urban landscape lake. The results of simulation show that water circulation system could effectively improve current speeds, reduce the proportion of stagnation area, and solve the problem of water quality deterioration caused by reclaimed water in the lake.

Distinct water activation on polar/non-polar facets of ZnO nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, He; Sun, Junming; Liu, Changjun

2015-11-01

ZnO nanoparticles with differing dominant facets were prepared and characterized by a complimentary of techniques such as X-ray diffraction, electron microscopy, temperature programmed desorption of H2O, and Fourier transform infrared spectroscopy analysis of adsorbed D2O. For the first time, water interaction/activation is compared on ZnO polar and non-polar facets. We report that non-polar facets exhibit high activity in water activation, which favors reactions such as ketonization and steam reforming in which dissociated water is involved. The distinct water dissociation on ZnO non-polar facets could be related to its facile formation of oxygen vacancies under realistic reaction conditions.

Surface-Water Conditions in Georgia, Water Year 2005

USGS Publications Warehouse

Painter, Jaime A.; Landers, Mark N.

2007-01-01

INTRODUCTION The U.S. Geological Survey (USGS) Georgia Water Science Center-in cooperation with Federal, State, and local agencies-collected surface-water streamflow, water-quality, and ecological data during the 2005 Water Year (October 1, 2004-September 30, 2005). These data were compiled into layers of an interactive ArcReaderTM published map document (pmf). ArcReaderTM is a product of Environmental Systems Research Institute, Inc (ESRI?). Datasets represented on the interactive map are * continuous daily mean streamflow * continuous daily mean water levels * continuous daily total precipitation * continuous daily water quality (water temperature, specific conductance dissolved oxygen, pH, and turbidity) * noncontinuous peak streamflow * miscellaneous streamflow measurements * lake or reservoir elevation * periodic surface-water quality * periodic ecological data * historical continuous daily mean streamflow discontinued prior to the 2005 water year The map interface provides the ability to identify a station in spatial reference to the political boundaries of the State of Georgia and other features-such as major streams, major roads, and other collection stations. Each station is hyperlinked to a station summary showing seasonal and annual stream characteristics for the current year and for the period of record. For continuous discharge stations, the station summary includes a one page graphical summary page containing five graphs, a station map, and a photograph of the station. The graphs provide a quick overview of the current and period-of-record hydrologic conditions of the station by providing a daily mean discharge graph for the water year, monthly statistics graph for the water year and period of record, an annual mean streamflow graph for the period of record, an annual minimum 7-day average streamflow graph for the period of record, and an annual peak streamflow graph for the period of record. Additionally, data can be accessed through the layer's link

Modeling the lag period and exponential growth of Listeria monocytogenes under conditions of fluctuating temperature and water activity values.

PubMed

Muñoz-Cuevas, Marina; Fernández, Pablo S; George, Susan; Pin, Carmen

2010-05-01

The dynamic model for the growth of a bacterial population described by Baranyi and Roberts (J. Baranyi and T. A. Roberts, Int. J. Food Microbiol. 23:277-294, 1994) was applied to model the lag period and exponential growth of Listeria monocytogenes under conditions of fluctuating temperature and water activity (a(w)) values. To model the duration of the lag phase, the dependence of the parameter h(0), which quantifies the amount of work done during the lag period, on the previous and current environmental conditions was determined experimentally. This parameter depended not only on the magnitude of the change between the previous and current environmental conditions but also on the current growth conditions. In an exponentially growing population, any change in the environment requiring a certain amount of work to adapt to the new conditions initiated a lag period that lasted until that work was finished. Observations for several scenarios in which exponential growth was halted by a sudden change in the temperature and/or a(w) were in good agreement with predictions. When a population already in a lag period was subjected to environmental fluctuations, the system was reset with a new lag phase. The work to be done during the new lag phase was estimated to be the workload due to the environmental change plus the unfinished workload from the uncompleted previous lag phase.

Effect on Quality Characteristics of Tomatoes Grown Under Well-Watered and Drought Stress Conditions.

PubMed

Klunklin, Warinporn; Savage, Geoffrey

2017-07-25

Tomatoes are one of the most nutritionally and economically important crops in New Zealand and around the world. Tomatoes require large amounts of water to grow well and are adversely affected by drought stress. However, few studies have evaluated the physicochemical characteristics of commercial tomatoes grown under water stress conditions. Four tomato cultivars (Incas, Marmande, Scoresby Dwarf, and Window Box Red) were grown in a greenhouse under well-watered and drought stress conditions and the tomatoes were harvested when ripe. The physicochemical properties and antioxidant contents of the fruits were compared. There were significant differences between cultivars in quality characteristics-such as dry matter, total soluble solids, and pH parameters-but there were no differences in the quality characteristics between the two treatments of the fruits ( p > 0.05); however, there were significant differences ( p < 0.05) in the antioxidant compositions (lycopene, total phenolics, and flavonoids) and antioxidant activities (DPPH and ABTS) of the fruits of both cultivars and treatments. Overall, these results indicated that tomatoes increased their bioactive compounds without changing any quality characteristics when exposed to water stress conditions.

Effect of soil and cover conditions on soil-water relationships

Treesearch

George R., Jr. Trimble; Charles E. Hale; H. Spencer Potter

1951-01-01

People who make flood-control surveys for the U.S. Department of Agriculture are concerned with the physical condition of the soils in the watersheds. The condition of the soil determines how fast water moves into and through the soil, and how much water is held in storage. The condition of the soil has a great influence on stream flow, erosion, floods and water supply...

Measuring water potential (activity) from free water to oven dryness.

PubMed

Wiebe, H H

1981-12-01

Water activities (potentials) in plant materials were measured over the range from free water to oven dryness with a Spanner thermocouple psychrometer. In a two-step procedure, water was first condensed on the thermocouple junction for several minutes. The sample was then inserted under the wet thermocouple and the maximum psychrometric cooling was measured in about 10 seconds. Calibration was with saturated salt slurries of known water activities. Psychrometric cooling was a nearly linear function of the water activity and of the negative log of the water potential. The psychrometric cooling to water activity relationship agreed with wetbulb temperature depression to relative humidity relationships given in tables. Water activities of wheat grains and leaves decreased sharply in a curvilinear fashion as their water contents decreased. Some problems of the procedure are discussed.

The antioxidant enzymes activity in the conditions of systemic hypersilicemia.

PubMed

Najda, J; Goss, M; Gmínski, J; Weglarz, L; Siemianowicz, K; Olszowy, Z

1994-07-01

The effect of an excessive inorganic silicon oral intake on the activity of basic antioxidant enzymes was studied in rats. Activities of superoxide dismutase, catalase, and glutathione peroxidase were measured in liver and kidney tissues of animals receiving per os sodium metasilicate nonahydrate (Na2SiO3.9H2O) (Sigma, [St. Louis, MO]) dissolved in their drinking water. A decrease of the activity of all the studied enzymes was found in the samples derived from the experimental group. The results obtained indicate the free oxygen radicals participation in the potential pathologic events in the conditions of systemic hypersilicemia.

Removing lead in drinking water with activated carbon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, R.M.; Kuennen, R.W.

A point-of-use (POU) granular activated carbon (GAC) fixed bed adsorber (FBA) was evaluated for reduction of soluble and insoluble lead from drinking water. Some of the factors which affect lead removal by GAC were evaluated, such as carbon type, solution pH, and a limited amount of work on competitive interactions. The design criteria for lead reduction by a POU device are also addressed. Minicolumns were used to evaluate the capacity of carbon for lead under a variety of conditions. The importance of surface chemistry of the carbon and the relationship with the pH of the water for lead reduction wasmore » demonstrated. Results indicate that a properly designed POU-GAC-FBA can reduce lead in drinking water to below the EPA action level of 15 ppb while being tested under a variety of conditions as specified under the National Sanitation Foundation (NSF) International Standard 53 test protocol. 37 refs., 9 figs., 1 tab.« less

Developing a state water plan: Ground-water conditions in Utah, spring of 1964

USGS Publications Warehouse

Arnow, Ted; Butler, R.G.; Mower, R.W.; Gates, Joseph S.; Cordova, R.M.; Carpenter, C.H.; Bjorklund, L.J.; Feltis, R.D.; Robinson, G.B. Jr.; Sandberg, G.W.

1964-01-01

This report is the first in a series of annual reports which will describe ground-water conditions in Utah. It was prepared cooperatively by the U.S. Geological Survey and the Utah Water and Power Board and was designed to provide the data for interested parties, such as legislators, administrators, and planners to keep abreast of changing ground-water conditions in the state. Because this report is the first of the series, it necessarily includes certain background and descriptive information which gives a broad general picture of ground-water conditions. Subsequent reports will discuss only changes that have taken place during the previous year.Many of the data used in the preparation of the report were collected by the Geological Survey in cooperation with the Utah State Engineer during past and continuing programs. The well-location map and some statistical information about numbers of wells in the State were prepared by digital computer from the Utah Resources Information System, University of Utah, utilizing records which were compiled largely from the files of the Utah State Engineer. R.E. Marsell, geological consultant to the Utah Water and Power Board, first suggested that this report be prepared.

Effect on Quality Characteristics of Tomatoes Grown Under Well-Watered and Drought Stress Conditions

PubMed Central

Klunklin, Warinporn; Savage, Geoffrey

2017-01-01

Tomatoes are one of the most nutritionally and economically important crops in New Zealand and around the world. Tomatoes require large amounts of water to grow well and are adversely affected by drought stress. However, few studies have evaluated the physicochemical characteristics of commercial tomatoes grown under water stress conditions. Four tomato cultivars (Incas, Marmande, Scoresby Dwarf, and Window Box Red) were grown in a greenhouse under well-watered and drought stress conditions and the tomatoes were harvested when ripe. The physicochemical properties and antioxidant contents of the fruits were compared. There were significant differences between cultivars in quality characteristics—such as dry matter, total soluble solids, and pH parameters—but there were no differences in the quality characteristics between the two treatments of the fruits (p > 0.05); however, there were significant differences (p < 0.05) in the antioxidant compositions (lycopene, total phenolics, and flavonoids) and antioxidant activities (DPPH and ABTS) of the fruits of both cultivars and treatments. Overall, these results indicated that tomatoes increased their bioactive compounds without changing any quality characteristics when exposed to water stress conditions. PMID:28757563

America's Soil and Water: Condition and Trends.

ERIC Educational Resources Information Center

1981

A review of conditions and trends regarding soil and water resources of rural nonfederal lands of the United States is presented in this publication. Maps, charts, and graphs illustrate the data collected on various aspects of soil and water use and practice. Topic areas considered include: (1) land use patterns; (2) classes of land; (3)…

Ground-Water Conditions and Studies in the Albany Area of Dougherty County, Georgia, 2007

USGS Publications Warehouse

Gordon, Debbie W.

2008-01-01

The U.S. Geological Survey (USGS) has been working with the Albany Water, Gas, and Light Commission to monitor ground-water quality and availability since 1977. This report presents an overview of ground-water conditions and studies in the Albany area of Dougherty County, Georgia, during 2007. Historical data are also presented for comparison with 2007 data. Ongoing monitoring activities include continuous water-level recording in 24 wells and monthly water-level measurements in 5 wells. During 2007, water levels in 21 of the continuous-recording wells were below normal, corresponding to lower than average rainfall. Ground-water samples collected from the Upper Floridan aquifer indicate that nitrate levels have decreased or remained about the same since 2006. Water samples were collected from the Flint River and wells at the Albany wellfield, and data were plotted on a trilinear diagram to show the percent composition of selected major cations and anions. Ground-water constituents (major cations and anions) of the Upper Floridan aquifer at the Albany wellfield are distinctly different from those in the water of the Flint River. To improve the understanding of the ground-water flow system and nitrate movement in the Upper Floridan aquifer, the USGS is developing a ground-water flow model in the southwestern Albany area of Georgia. The model is being calibrated to simulate periods of dry (October 1999) and relatively wet (March 2001) hydrologic conditions. Preliminary water-level simulations indicate a generally good fit to measured water levels.

Condition Assessment for Drinking Water Systems

EPA Science Inventory

This project will enable a systematic approach to characterizing the value of condition assessment of drinking water mains that will provide the basis for better communication among, and decisions by, stakeholders regarding goals and priorities for research, development, and tech...

National water-information clearinghouse activities; ground-water perspective

USGS Publications Warehouse

Haupt, C.A.; Jensen, R.A.

1988-01-01

The US Geological Survey (USGS) has functioned for many years as an informal clearinghouse for water resources information, enabling users to access groundwater information effectively. Water resources clearinghouse activities of the USGS are conducted through several separate computerized water information programs that are involved in the collection, storage, retrieval, and distribution of different types of water information. The following USGS programs perform water information clearinghouse functions and provide the framework for a formalized National Water-Information Clearinghouse: (1) The National Water Data Exchange--a nationwide confederation of more than 300 Federal, State, local, government, academic, and private water-oriented organizations that work together to improve access to water data; (2) the Water Resources Scientific Information Center--acquires, abstracts, and indexes the major water-resources-related literature of the world, and provides this information to the water resources community; (3) the Information Transfer Program--develops innovative approaches to transfer information and technology developed within the USGS to audiences in the public and private sectors; (4) the Hydrologic Information Unit--provides responses to a variety of requests, both technical and lay-oriented, for water resources information , and helps efforts to conduct water resources research; (5) the Water Data Storage and Retrieval System--maintains accessible computerized files of hydrologic data collected nationwide, by the USGS and other governmental agencies, from stream gaging stations, groundwater observation wells, and surface- and groundwater quality sampling sites; (6) the Office of Water Data Coordination--coordinate the water data acquisition activities of all agencies of the Federal Government, and is responsible for the planning, design, and inter-agency coordination of a national water data and information network; and (7) the Water Resources Research

Measuring Water Potential (Activity) from Free Water to Oven Dryness 1

PubMed Central

Wiebe, Herman H.

1981-01-01

Water activities (potentials) in plant materials were measured over the range from free water to oven dryness with a Spanner thermocouple psychrometer. In a two-step procedure, water was first condensed on the thermocouple junction for several minutes. The sample was then inserted under the wet thermocouple and the maximum psychrometric cooling was measured in about 10 seconds. Calibration was with saturated salt slurries of known water activities. Psychrometric cooling was a nearly linear function of the water activity and of the negative log of the water potential. The psychrometric cooling to water activity relationship agreed with wetbulb temperature depression to relative humidity relationships given in tables. Water activities of wheat grains and leaves decreased sharply in a curvilinear fashion as their water contents decreased. Some problems of the procedure are discussed. Images PMID:16662081

Water-quality assessment of the central Nebraska basins; summary of data for recent conditions through 1990

USGS Publications Warehouse

Zelt, R.B.; Jordan, P.R.

1993-01-01

Among the first activities undertaken in each National Water-Quality Assessment (NAWQA) program study-unit investigation are compilation, screening, and statistical summary of available data concerning recent, general water-quality conditions in the study unit. This report (1) identifies which of the existing water-quality data are suitable for characterizing general conditions in a nationally consistent manner and (2) describes, to the extent possible, recent, general water-quality conditions in the Central Nebraska Basins. The study unit con- sists of the area drained by the Platte River between the confluence of the North Platte and South Platte Rivers near North Platte downstream to its confluence with the Missouri River south of Omaha. The report includes (1) a description of the sources and characteristics of water-quality data that are available, (2) a description of the approach used for screening data to identify a subset of the data suitable for summary and comparisons, (3) a presen- tation of the results of statistical and graphical summaries of recent, general water-quality con- ditions, and (4) comparisons of recent, general water-quality conditions to established national water-quality criteria, where applicable. Stream- and lake-water data are summarized for selected sampling sites, and data are summarized by major subunits of the study unit (the Sandhills, Loess Hills, Glaciated Area, and Platte Valley subunits) for streambed-sediment, fish-tissue, aquatic- ecological, and ground-water data. The summaries focus on the central tendencies and typical variation in the data and use nonparametric statistics such as frequencies and percentile values.

Enterococcus faecalis Gene Transfer under Natural Conditions in Municipal Sewage Water Treatment Plants†

PubMed Central

Marcinek, Herbert; Wirth, Reinhard; Muscholl-Silberhorn, Albrecht; Gauer, Matthias

1998-01-01

The ability of Enterococcus faecalis to transfer various genetic elements under natural conditions was tested in two municipal sewage water treatment plants. Experiments in activated sludge basins of the plants were performed in a microcosm which allowed us to work under sterile conditions; experiments in anoxic sludge digestors were performed in dialysis bags. We used the following naturally occurring genetic elements: pAD1 and pIP1017 (two so-called sex pheromone plasmids with restricted host ranges, which are transferred at high rates under laboratory conditions); pIP501 (a resistance plasmid possessing a broad host range for gram-positive bacteria, which is transferred at low rates under laboratory conditions); and Tn916 (a conjugative transposon which is transferred under laboratory conditions at low rates to gram-positive bacteria and at very low rates to gram-negative bacteria). The transfer rate between different strains of E. faecalis under natural conditions was, compared to that under laboratory conditions, at least 105-fold lower for the sex pheromone plasmids, at least 100-fold lower for pIP501, and at least 10-fold lower for Tn916. In no case was transfer from E. faecalis to another bacterial species detected. By determining the dependence of transfer rates for pIP1017 on bacterial concentration and extrapolating to actual concentrations in the sewage water treatment plant, we calculated that the maximum number of transfer events for the sex pheromone plasmids between different strains of E. faecalis in the municipal sewage water treatment plant of the city of Regensburg ranged from 105 to 108 events per 4 h, indicating that gene transfer should take place under natural conditions. PMID:9464401

Condition Assessment for Drinking Water Transmission and Distribution Mains

EPA Science Inventory

This project seeks to improve the capability to characterize the condition of water infrastructure. The integrity of buried drinking water mains is critical, as it influences water quality, losses, pressure and cost. This research complements the U.S. Environmental Protection A...

Optimization conditions for extracting polysaccharide from Angelica sinensis and its antioxidant activities.

PubMed

Tian, Suyang; Hao, Changchun; Xu, Guangkuan; Yang, Juanjuan; Sun, Runguang

2017-10-01

In this study, polysaccharides from Angelica sinensis were extracted using the ultrasound-assisted extraction method. Based on the results of single factor experiments and orthogonal tests, three independent variables-water/raw material ratio, ultrasound time, and ultrasound power-were selected for investigation. Then, we used response surface methodology to optimize the extraction conditions. The experimental data were fitted to a quadratic equation using multiple regression analysis, and the optimal conditions were as follows: water/raw material ratio, 43.31 mL/g; ultrasonic time, 28.06 minutes; power, 396.83 W. Under such conditions, the polysaccharide yield was 21.89±0.21%, which was well matched with the predicted yield. In vitro assays, scavenging activity of superoxide anion radicals, hydroxyl radicals, and 2,2-diphenyl-1-picry-hydrazyl radical showed that polysaccharides had certain antioxidant activities and that hydroxyl radicals have a remarkable scavenging capability. Therefore, these studies provide reference for further research and rational development of A. sinensis polysaccharide. Copyright © 2016. Published by Elsevier B.V.

Hydrologic Conditions in Kansas, water year 2015

USGS Publications Warehouse

May, Madison R.

2016-03-31

The U.S. Geological Survey (USGS), in cooperation with Federal, State, and local agencies, maintains a long-term network of hydrologic monitoring sites in Kansas. In 2015, the network included about 200 real-time streamgages (hereafter referred to as “gages”), 12 real-time reservoir-level monitoring stations, and 30 groundwater-level monitoring wells. These data and associated analyses provide a unique overview of hydrologic conditions and help improve the understanding of Kansas’s water resources.Real-time data are verified by the USGS throughout the year with regular measurements of streamflow, lake levels, and groundwater levels. These data are used in protecting life and property; and managing water resources for agricultural, industrial, public supply, ecological, and recreational purposes. Yearly hydrologic conditions are characterized by comparing statistical analyses of current and historical water year (WY) data for the period of record. A WY is the 12-month period from October 1 through September 30 and is designated by the year in which it ends.

Field Demonstration of Innovative Condition Assessment Technologies for Water Mains: Leak Detection and Location

EPA Science Inventory

Three leak detection/location technologies were demonstrated on a 76-year-old, 2,057-ft-long portion of a cement-lined, 24-in. cast iron water main in Louisville, KY. This activity was part of a series of field demonstrations of innovative leak detection/location and condition a...

Modeling Bacteria-Water Interactions in Soil: EPS Dynamics Under Evaporative Conditions

NASA Astrophysics Data System (ADS)

Furrer, J.; Hinestroza, H. F.; Guo, Y. S.; Gage, D. J.; Cho, Y. K.; Shor, L. M.

2017-12-01

The soil habitat represents a major linkage between the water and carbon cycles: the ability of soils to sequester or release carbon is determined primarily by soil moisture. Water retention and distribution in soils controls the abundance and activity of soil microbes. Microbes in turn impact water retention by creating biofilms, composed of extracellular polymeric substances (EPS). We model the effects of bacterial EPS on water retention at the pore scale. We use the lattice Boltzmann method (LBM), a well-established fluid dynamics modeling platform, and modify it to include the effects of water uptake and release by the swelling/shrinking EPS phase. The LB model is implemented in 2-D, with a non-ideal gas equation of state that allows condensation and evaporation of fluid in pore spaces. Soil particles are modeled according to experimentally determined particle size distributions and include realistic pore geometries, in contrast to many soil models which use spherical soil particles for simplicity. Model results are compared with evaporation experiments in soil micromodels and other simpler experimental systems, and model parameters are tuned to match experimental results. Drying behavior and solid-gel contact angle of EPS produced by the soil bacteria Sinorhizobium meliloti has been characterized and compared to the behavior of deionized water under the same conditions. The difference in behavior between the fluids is used to parameterize the model. The model shows excellent qualitative agreement for soil micromodels with both aggregated and non-aggregated particle arrangements under no-EPS conditions, and reproduces realistic drying behavior for EPS. This work represents a multi-disciplinary approach to understanding microbe-soil interactions at the pore scale.

Summary of hydrologic conditions in Kansas, water year 2014

USGS Publications Warehouse

Robison, Andrew L.

2015-01-01

The U.S. Geological Survey Kansas Water Science Center, in cooperation with Federal, State, and local agencies, maintains a long-term network of hydrologic monitoring gages in the State of Kansas. These include 206 real-time streamgages, 12 real-time reservoir-level monitoring stations, and 32 groundwater monitoring wells. These data and associated analyses, accumulated over time, provide a unique overview of hydrologic conditions and help improve our understanding of Kansas’s water resources. Yearly hydrologic conditions are determined by comparing statistical analyses of current and historical water year data for the period of record. These data are used in protecting life and property, and managing water resources for agricultural, industrial, public supply, ecological, and recreational purposes.

Water-resources activities in New England, fiscal year 1993

USGS Publications Warehouse

Orlando, M.F.

1994-01-01

The U.S. Geological Survey has 82 active or complete-except-report projects of hydrologic investigations ongoing within the New England Program Area. Of this total, 23 are data projects. Data projects contain statistics and data on the conditions of surface water, ground water, water quality and (or) water use for the study area. There currently are six data projects in Connecticut, five in Maine, four in Massachusetts, four in Rhode Island, and four in New Hampshire and Vermont. The remaining 59 of these projects are interpretive projects. Interpretive projects include research, aerial appraisal, and other hydrologic studies and include projects as diverse as (1) determining the direction of ground-water flow at a toxic site, (2) predicting the effect of acid rain on water quality of a reservoir, and (3) estimating yields of aquifers on Cape Cod. Of the interpretive projects, 26 are in Massachusetts, 17 in Connecticut, 17 are in New Hampshire and Vermont, 6 are in Maine, and 3 in Rhode Island. The report is compiled from project descriptions for fiscal year 1993. It briefly describes the water-resources activities and projects that were active in each District of the USGS, Water Resources Division, New England Program Area of September 30, 1993. Cooperator or funding source, problem statements, objectives, approaches, progress, and plans for next year are described for each project. The project area is located on a map of the appropriate State(s). The report contains a bibliography, by District and by author, of reports completed since 1977.

A novel theoretical probe of the SrTiO3 surface under water-splitting conditions

NASA Astrophysics Data System (ADS)

Letchworth-Weaver, Kendra; Gunceler, Deniz; Arias, Tomás; Plaza, Manuel; Huang, Xin; Brock, Joel; Rodriguez-López, Joaquin; Abruña, Hector

2014-03-01

Understanding the reaction mechanisms required to generate hydrogen fuel by photoelectrolysis of water is essential to energy conversion research. These reaction pathways are strongly influenced by the geometry and electronic structure of the electrode surface under water-splitting conditions. Electrochemical microscopy has demonstrated that biasing a SrTiO3 (001) surface can lead to an increase in water-splitting activity. In operando X-ray reflectivity measurements at the Cornell High Energy Synchrotron Source (CHESS) correlate this increase in activity to a significant reorganization in the surface structure but are unable to determine the exact nature of this change. Joint Density-Functional Theory (JDFT), a rigorous yet computationally efficient alternative to molecular dynamics, provides a quantum-mechanical description of an electrode surface in contact with an aqueous environment, and a microscopically detailed description of the interfacial liquid structure. Our JDFT calculations determine the structure of the activated SrTiO3 surface and explore why it is correlated with higher activity for water splitting. With no empirical parameters whatsoever, we predict the X-ray crystal truncation rods for SrTiO3, finding excellent agreement with experiment. Funded by the Energy Materials Center at Cornell (EMC2).

Ground-water conditions in Georgia, 1999

USGS Publications Warehouse

Cressler, Alan M.

2000-01-01

Ground-water conditions in Georgia during 1999 and for the period of record were evaluated using data from U.S. Geological Survey ground-water-level and ground-water-quality monitoring networks. Data for 1999 included in this report are from continuous water-level records from 130 wells and chloride analyses from 14 wells. Data from one well is incomplete because data collection was discontinued. Chloride concentration in water from the Upper Floridan aquifer in most of coastal Georgia was within drinking-water standards established by the Georgia Department of Natural Resources and the U.S. Environmental Protection Agency. In the Savannah area, chloride concentration has not changed appreciably with time. However, chloride concentration in water from some wells that tap the Floridan aquifer system in the Brunswick area exceeds the drinking-water standards. Ground-water-level and ground-water-quality data are essential for water assessment and management. Ground-water-level fluctuations and trends can be used to estimate changes in aquifer storage resulting from the effects of ground-water withdrawal and recharge from precipitation. These data can be used to address water-management needs and to evaluate the effects of management and conservation programs. As part of the ground-water investigations conducted by the U.S. Geological Survey (USGS), in cooperation with the State of Georgia and city and county governments, a Statewide water-level-measurement program was started in 1938. Initially, this program consisted of an observation-well network in the coastal area of Georgia to monitor variations in ground-water storage and quality. Additional wells were later included in areas where data could be used to aid in water resources development and management. During 1999, periodic water-level measurements were made in 46 wells, and continuous water-level measurements were obtained from 165 wells. Continuous water-level records were obtained using analog (pen and chart

Water activities of NaClO4, Ca(ClO4)2, and Mg(ClO4)2 brines from experimental heat capacities: Water activity >0.6 below 200 K

NASA Astrophysics Data System (ADS)

Toner, J. D.; Catling, D. C.

2016-05-01

Perchlorate salts found on Mars are extremely hygroscopic and form low eutectic temperature aqueous solutions, which could allow liquid water to exist on Mars despite cold and dry conditions. The formation, dynamics, and potential habitability of perchlorate salt solutions can be broadly understood in terms of water activity. Water activity controls condensation and evaporation of water vapor in brines, deliquescence and efflorescence of crystalline salts, and ice formation during freezing. Furthermore, water activity is a basic parameter defining the habitability of aqueous solutions. Despite the importance of water activity, its value in perchlorate solutions has only been measured at 298.15 K and at the freezing point of water. To address this lack of data, we have determined water activities in NaClO4, Ca(ClO4)2, and Mg(ClO4)2 solutions using experimental heat capacities measured by Differential Scanning Calorimetry. Our results include concentrations up to near-saturation and temperatures ranging from 298.15 to 178 K. We find that water activities in NaClO4 solutions increase with decreasing temperature, by as much as 0.25 aw from 298.15 to 178 K. Consequently, aw reaches ∼0.6-0.7 even for concentrations up to 15 molal NaClO4 below 200 K. In contrast, water activities in Ca(ClO4)2 and Mg(ClO4)2 solutions generally decrease with decreasing temperature. The temperature dependence of water activity indicates that low-temperature NaClO4 solutions will evaporate and deliquesce at higher relative humidity, crystallize ice at higher temperature, and potentially be more habitable for life (at least in terms of water activity) compared to solutions at 298.15 K. The opposite effects occur in Ca(ClO4)2 and Mg(ClO4)2 solutions.

Use of RORA for Complex Ground-Water Flow Conditions

USGS Publications Warehouse

Rutledge, A.T.

2004-01-01

The RORA computer program for estimating recharge is based on a condition in which ground water flows perpendicular to the nearest stream that receives ground-water discharge. The method, therefore, does not explicitly account for the ground-water-flow component that is parallel to the stream. Hypothetical finite-difference simulations are used to demonstrate effects of complex flow conditions that consist of two components: one that is perpendicular to the stream and one that is parallel to the stream. Results of the simulations indicate that the RORA program can be used if certain constraints are applied in the estimation of the recession index, an input variable to the program. These constraints apply to a mathematical formulation based on aquifer properties, recession of ground-water levels, and recession of streamflow.

Using Water Isotope Tracers to Investigate Past and Present Water Balance Conditions in the Old Crow Flats, Yukon Territory

NASA Astrophysics Data System (ADS)

Turner, K.; Wolfe, B. B.; Edwards, T. W.

2010-12-01

woodland or large willow land cover that allows for greater snowpack development in contrast to rainfall-dominated lakes, which have catchments dominated by tundra vegetation that are typically smaller relative to lake areas. Precipitation during the three-year study was highly variable and strongly influenced water balance conditions. For example, in years of reduced precipitation, many rainfall-dominated lakes are susceptible to becoming evaporation-dominated late in the ice-free season, whereas prolonged wet conditions can lead to increased thermokarst activity and subsequent lake drainage events. Approaches used in this modern water balance study are readily transferable to other northern thermokarst landscapes in order to develop greater insight into landscape-scale responses to ongoing climate change. Additionally, knowledge of modern water balance variability throughout the OCF provides the basis for interpretation of past limnological conditions, which are being determined through ongoing paleolimnological analyses. Key findings will be used to enhance our ability to anticipate how the water balance of lakes in the OCF will respond to future climate change.

Treatment of perfluoroalkyl acids by heat-activated persulfate under conditions representative of in situ chemical oxidation.

PubMed

Bruton, Thomas A; Sedlak, David L

2018-04-21

Perfluoroalkyl acids (PFAAs) are a class of organic contaminants notable for their extreme persistence. The unique chemical properties of these compounds make them difficult to remove from water using most standard water treatment techniques. To gain insight into the possibility of remediating contaminated groundwater by in situ chemical oxidation with heat-activated persulfate, PFAA removal and the generation of transformation products were evaluated under laboratory conditions. Solution pH had a strong influence on the removal of perfluorooctanoic acid (PFOA), resulting in its transformation into shorter-chain perfluorocarboxylic acids (PFCAs) at pH values below 3. The presence of chloride and aquifer sediments decreased the efficiency of the process by less than 25% under conditions likely to be encountered in drinking water aquifers. Perfluorooctane sulfonic acid (PFOS) was not transformed by heat-activated persulfate under any of the conditions tested. Despite challenges related to the need to manipulate aquifer pH, the possible generation of undesirable short-chain PFCAs and chlorate, and metals mobilization, heat-activated persulfate may be a useful treatment technology for sites contaminated with PFCAs and fluorotelomer-based compounds, including those used in current-generation aqueous film-forming foams. Copyright © 2018 Elsevier Ltd. All rights reserved.

Water-resources activities in Ohio, 1986 (water fact sheet)

USGS Publications Warehouse

Hindall, S.M.

1986-01-01

The Ohio District of the Water Resources Division, U.S. Geological Survey, provides information on Ohio 's water resources for the overall benefit of the State and the Nation. An integral part of the Survey 's mission is to conduct investigations of the Nation 's land, mineral, and water resources, and to publish and disseminate the information needed to understand, to plan the use of, and to manage these resources. The activities fall into eight broad categories: collection of hydrologic data; water resources investigations and assessments; basic and problem-oriented hydrologic and water related research; acquisition of information useful in predicting and delineating water related natural hazards; coordination of the activities of all Federal agencies in the acquisition of water data, and operation of water information centers; dissemination of data and the results of investigations; provision of scientific and technical assistance in hydrologic studies; and the administration of the State Water Resources Research Institute Program and the National Water Resources Research Grant Program. (Lantz-PTT)

Toxicity assessment of multi-walled carbon nanotubes on Cucurbita pepo L. under well-watered and water-stressed conditions.

PubMed

Hatami, Mehrnaz

2017-08-01

The rapid increase in the production and application of various types of nanomaterials increases the possibility of their presence in total environment, which subsequently raises concerns about their potential threats to the first trophic level of organisms, specifically under varying environmental constraints. In this work, seeds of Cucurbita pepo L. were cultured in MS basal medium exposed to multi-walled carbon nanotubes (MWCNTs) at different concentrations (0, 125, 250, 500 and 1000μgmL -1 ) under two levels of water potential, well-watered (0MPa) and water stress (-1.5MPa) induced by polyethylene glycol (PEG 6000) for 14 days. Seeds exposed to MWCNTs showed reduction in germination percentage, root and shoot length, biomass accumulation and vigor index in a dose-dependent manner. However, seedlings germinated in MWCNTs-fortified media had significantly lower germination and growth attributes than those of control under water stress conditions. This happened due to increased oxidative injury indices including hydrogen peroxide (H 2 O 2 ), and malondialdehyde (MDA) contents, as well as electrolyte leakage index (ELI) of tissues. The impaired morpho-physiological and biochemical processes of seedlings exposed to different concentrations of MWCNTs under both PEG-induced stress and non-stress growing conditions were consequence of changes in the activation of various cellular antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (POD). Taken together, our findings reveal that MWCNTs played negative role on seed germination and subsequent growth of C. pepo L. seedlings under both levels of water potential. Copyright © 2017 Elsevier Inc. All rights reserved.

Coagulation removal of humic acid-stabilized carbon nanotubes from water by PACl: influences of hydraulic condition and water chemistry.

PubMed

Ma, Si; Liu, Changli; Yang, Kun; Lin, Daohui

2012-11-15

Discharged carbon nanotubes (CNTs) can adsorb the widely-distributed humic acid (HA) in aquatic environments and thus be stabilized. HA-stabilized CNTs can find their way into and challenge the potable water treatment system. This study investigated the efficiency of coagulation and sedimentation techniques in the removal of the HA-stabilized multi-walled carbon nanotubes (MWCNTs) using polyaluminum chloride (PACl) as a coagulant, with a focus on the effects of hydraulic conditions and water chemistry. Stirring speeds in the mixing and reacting stages were gradually changed to examine the effect of the hydraulic conditions on the removal rate. The stirring speed in the reacting stage affected floc formation and thereby had a greater impact on the removal rate than the stirring speed in the mixing stage. Water chemistry factors such as pH and ionic strength had a significant effect on the stability of MWCNT suspension and the removal efficiency. Low pH (4-7) was favorable for saving the coagulant and maintaining high removal efficiency. High ionic strength facilitated the destabilization of the HA-stabilized MWCNTs and thereby lowered the required PACl dosage for the coagulation. However, excessively high ionic strength (higher than the critical coagulation concentration) decreased the maximum removal rate, probably by inhibiting ionic activity of PACl hydrolyzate in water. These results are expected to shed light on the potential improvement of coagulation removal of aqueous stabilized MWCNTs in water treatment systems. Copyright © 2012 Elsevier B.V. All rights reserved.

Water resources activities of the USGS, 1987

USGS Publications Warehouse

Moore, John E.; Cardin, C. William

1987-01-01

Effective management of water resources requires an understanding of hydrologic systems and the factors that determine the distribution, availability, and quality of water. Within the Federal Government, the U.S. Geological Survey has the principal responsibility for providing hydrologic information and for appraising the Nation's water resources. The water resources activities of the U.S. Geological Survey are diverse, ranging from research investigations of specific aspects of the hydrologic cycle to large programs of regional water-resources investigations, such as the Regional Aquifer System Analyses.This report describes the U.S. Geological Survey's water resources activities. Some activities, such as the acid rain program, are mandated by line items in the Survey's fiscal year 1987 budget. Others, such as floods, sediment, and snow and ice, are topics of general interest to the water resources community. Still others are related to current water issues, such as nonpoint sources of pollution, the irrigation drainage problem of the western San Joaquin Valley, and national ground-water protection.In many cases, there is considerable overlap in the topical descrip-tions. The Survey's water resources research program, for example, conducts investigations that are applicable to virtually all of the activities listed in this book. Similarly, projects in the Federal-State Cooperative Program cover multiple aspects of water resources. For these reasons, the sums associated with funding for each of the activities listed exceeds by a considerable amount the Survey's budget for water resources activities.The report first describes the water-resources mission of the U.S. Geological Survey and discusses the principal sources of funds that support the activities. The remainder of the report consists of descriptions of 39 of the most significant water resources activities. An index appears at the end of the report.Each description of a significant water activity has the

Magnificent Ground Water Connection. [Sample Activities].

ERIC Educational Resources Information Center

Environmental Protection Agency, Washington, DC.

Water conservation and usage is an important concept in science. This document, geared specifically to New England, provides many activities for protecting and discussing ground water situations. Sample activities for grades K-6 include: (1) All the Water in the World; (2) The Case of the Disappearing Water; (3) Deep Subjects--Wells and Ground…

Condition Assessment Technologies for Water Transmission and Distribution Systems

EPA Science Inventory

As part of the U.S. Environmental Protection Agency’s (EPA’s) Aging Water Infrastructure Research Program, this research was conducted to identify and characterize the state of the technology for structural condition assessment of drinking water transmission and distribution syst...

Water surface elevation from the upcoming SWOT mission under different flows conditions

NASA Astrophysics Data System (ADS)

Domeneghetti, Alessio; Schumann, Guy J. P.; Wei, Rui; Frasson, Renato P. M.; Durand, Michael; Pavelsky, Tamlin; Castellarin, Attilio; Brath, Armando

2017-04-01

The upcoming SWOT (Surface Water and Ocean Topography) satellite mission will provide unprecedented bi-dimensional observations of terrestrial water surface heights along rivers wider than 100m. Despite the literature reports several activities showing possible uses of SWOT products, potential and limitations of satellite observations still remain poorly understood and investigated. We present one of the first analyses regarding the spatial observation of water surface elevation expected from SWOT for a 140 km reach of the middle-lower portion of the Po River, in Northern Italy. The river stretch is characterized by a main channel varying from 100-500 m in width and a floodplain delimited by a system of major embankments that can be as wide as 5 km. The reconstruction of the hydraulic behavior of the Po River is performed by means of a quasi-2D model built with detailed topographic and bathymetric information (LiDAR, 2m resolution), while the simulation of remotely sensed hydrometric data is performed with a SWOT simulator that mimics the satellite sensor characteristics. Referring to water surface elevations associated with different flow conditions (maximum, minimum and average flow) this work characterizes the spatial observations provided by SWOT and highlights the strengths and limitations of the expected products. The analysis provides a robust reference for spatial water observations that will be available from SWOT and assesses possible effects of river embankments, river width and river topography under different hydraulic conditions. Results of the study characterize the expected accuracy of the upcoming SWOT mission and provide additional insights towards the appropriate exploitation of future hydrological observations.

Overview of EPA Research On Condition Assessment of Drinking Water Mains

EPA Science Inventory

This slide presentation provides an overview of condition assessment research that is part of EPA Office of Research and Development’s Aging Water Infrastructure Research Plan (AWIRP). The primary focus is on a water main condition assessment technology forum and associated whit...

Primer on Condition Curves for Water Mains

EPA Science Inventory

ABSTRACT The development of economical tools to prioritize pipe renewal based upon structural condition and remaining asset life is essential to effectively manage water infrastructure assets for both large and small diameter pipes. One tool that may facilitate asset management...

Relationship between body condition of American alligators and water depth in the Everglades, Florida

USGS Publications Warehouse

Fujisaki, Ikuko; Rice, Kenneth G.; Pearlstine, Leonard G.; Mazzotti, Frank J.

2009-01-01

Feeding opportunities of American alligators (Alligator mississippiensis) in freshwater wetlands in south Florida are closely linked to hydrologic conditions. In the Everglades, seasonally and annually fluctuating surface water levels affect populations of aquatic organisms that alligators consume. Since prey becomes more concentrated when water depth decreases, we hypothesized an inverse relationship between body condition and water depth in the Everglades. On average, condition of adult alligators in the dry season was significantly higher than in the wet season, but this was not the case for juveniles/subadults. The correlation between body condition and measured water depth at capture locations was weak; however, there was a significant negative correlation between the condition and predicted water depth prior to capture for all animals except for spring juveniles/subadults which had a weak positive condition-water depth relationship. Overall, a relatively strong inverse correlation occurred at 10-49 days prior to the capture day, suggesting that current body condition of alligators may depend on feeding opportunities during that period. Fitted regression of body condition on water depth (mean depth of 10 days when condition-water depth correlation was greatest) resulted in a significantly negative slope, except for spring adult females and spring juveniles/subadults for which slopes were not significantly different from zero. Our results imply that water management practices may be critical for alligators in the Everglades since water depth can affect animal condition in a relatively short period of time.

GROUND WATER QUALITY SURROUNDING LAKE TEXOMA DURING DROUGHT CONDITIONS

EPA Science Inventory

Water quality data from 55 producing monitoring wells during drought conditions surrounding Lake Texoma, located on the border of Oklahoma and Texas, was compared to assess the influence of drought on groundwater quality. The main water quality parameter measured was nitrate, an...

Condition Assessment of Drinking Water Transmission and Distribution Systems

EPA Science Inventory

Condition assessment of water transmission and distribution mains is the collection of data and information through direct and/or indirect methods, followed by analysis of the data and information, to make a determination of the current and/or future structural, water quality, an...

42 CFR 494.40 - Condition: Water and dialysate quality.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 5 2013-10-01 2013-10-01 false Condition: Water and dialysate quality. 494.40 Section 494.40 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) STANDARDS AND CERTIFICATION CONDITIONS FOR COVERAGE FOR END-STAGE RENAL DISEASE FACILITIES Patient Safety § 494.40 Condition: Wate...

42 CFR 494.40 - Condition: Water and dialysate quality.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 5 2012-10-01 2012-10-01 false Condition: Water and dialysate quality. 494.40 Section 494.40 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) STANDARDS AND CERTIFICATION CONDITIONS FOR COVERAGE FOR END-STAGE RENAL DISEASE FACILITIES Patient Safety § 494.40 Condition: Wate...

42 CFR 494.40 - Condition: Water and dialysate quality.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 5 2014-10-01 2014-10-01 false Condition: Water and dialysate quality. 494.40 Section 494.40 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) STANDARDS AND CERTIFICATION CONDITIONS FOR COVERAGE FOR END-STAGE RENAL DISEASE FACILITIES Patient Safety § 494.40 Condition: Wate...

Streamflow, water-quality, and biological conditions in the Big Black Creek basin, St. Clair County, Alabama, 1997

USGS Publications Warehouse

Journey, Celeste A.; Clark, Amy E.; Stricklin, Victor E.

1998-01-01

In 1997 synoptic streamflow, water-quality, and biological investi- gations in the Big Black Creek Basin were conducted by the U.S. Geological Survey in cooperation with the City of Moody, St. Clair County, and the Birmingham Water Works Board. Data obtained during these synoptic investigations provide a one-time look at the streamflow and water-quality conditions in the Big Black Creek Basin during a stable, base-flow period when streamflow originated only from ground-water discharge. These data were used to assess the degree of water-quality degradation in the Big Black Creek Basin from land-use activities in the basin, including leakage of leachate from the Acmar Regional Land- fill. Biological data from the benthic invertebrate community investigation provided an assessment of the cumulative effects of stream conditions on organisms in the basin. The synoptic measurement of streamflow at 28 sites was made during a period of baseflow on August 27, 1997. Two stream reaches above the landfill lost water to the ground-water system, but those below the landfill had significantly higher ground-water gains. If significant leakage of leachate from the landfill had occurred during the measurement period, the distribution of ground-water discharge suggests that leachate would travel relatively short distances before resurfacing as ground-water discharge to the stream. Benthic invertebrate communities were sampled at four sites in the Big Black Creek Basin during July 16-17, 1997. Based on Alabama Department of Environmental Management criteria and on comparison with a nearby unimparied reference site, the benthic invertebrate communities at the sites sampled were considered unimpaired or only slightly impaired during the sample period. This would imply that landfill and coal-mining activities did not have a detrimental effect on the benthic invertebrate communities at the time of the study. Synoptic water-column samples were collected at nine sites on Big Black Creek and

Photogeneration of active formate decomposition catalysts to produce hydrogen from formate and water

DOEpatents

King, Jr., Allen D.; King, Robert B.; Sailers, III, Earl L.

1983-02-08

A process for producing hydrogen from formate and water by photogenerating an active formate decomposition catalyst from transition metal carbonyl precursor catalysts at relatively low temperatures and otherwise mild conditions is disclosed. Additionally, this process may be expanded to include the generation of formate from carbon monoxide and hydroxide such that the result is the water gas shift reaction.

Predicting Near-Term Water Quality from Satellite Observations of Watershed Conditions

NASA Astrophysics Data System (ADS)

Weiss, W. J.; Wang, L.; Hoffman, K.; West, D.; Mehta, A. V.; Lee, C.

2017-12-01

Despite the strong influence of watershed conditions on source water quality, most water utilities and water resource agencies do not currently have the capability to monitor watershed sources of contamination with great temporal or spatial detail. Typically, knowledge of source water quality is limited to periodic grab sampling; automated monitoring of a limited number of parameters at a few select locations; and/or monitoring relevant constituents at a treatment plant intake. While important, such observations are not sufficient to inform proactive watershed or source water management at a monthly or seasonal scale. Satellite remote sensing data on the other hand can provide a snapshot of an entire watershed at regular, sub-monthly intervals, helping analysts characterize watershed conditions and identify trends that could signal changes in source water quality. Accordingly, the authors are investigating correlations between satellite remote sensing observations of watersheds and source water quality, at a variety of spatial and temporal scales and lags. While correlations between remote sensing observations and direct in situ measurements of water quality have been well described in the literature, there are few studies that link remote sensing observations across a watershed with near-term predictions of water quality. In this presentation, the authors will describe results of statistical analyses and discuss how these results are being used to inform development of a desktop decision support tool to support predictive application of remote sensing data. Predictor variables under evaluation include parameters that describe vegetative conditions; parameters that describe climate/weather conditions; and non-remote sensing, in situ measurements. Water quality parameters under investigation include nitrogen, phosphorus, organic carbon, chlorophyll-a, and turbidity.

Light field and water clarity simulation of natural environments in laboratory conditions

NASA Astrophysics Data System (ADS)

Pe'eri, Shachak; Shwaery, Glenn

2012-06-01

Simulation of natural oceanic conditions in a laboratory setting is a challenging task, especially when that environment can be miles away. We present an attempt to replicate the solar radiation expected at different latitudes with varying water clarity conditions up to 30 m in depth using a 2.5 m deep engineering tank at the University of New Hampshire. The goals of the study were: 1) to configure an underwater light source that produced an irradiance spectrum similar to natural daylight with the sun at zenith and at 60° under clear atmospheric conditions, and 2) to monitor water clarity as a function of depth. Irradiance was measured using a spectra-radiometer with a cosine receiver to analyze the output spectrum of submersed lamps as a function of distance. In addition, an underwater reflection method was developed to measure the diffuse attenuation coefficient in real time. Two water clarity types were characterized, clear waters representing deep, open-ocean conditions, and murky waters representing littoral environments. Results showed good correlation between the irradiance measured at 400 nm to 600 nm and the natural daylight spectrum at 3 m from the light source. This can be considered the water surface conditions reference. Using these methodologies in a controlled laboratory setting, we are able to replicate illumination and water conditions to study the physical, chemical and biological processes on natural and man-made objects and/or systems in simulated, varied geographic locations and environments.

Comparison of doubly labeled water with respirometry at low- and high-activity levels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Westerterp, K.R.; Brouns, F.; Saris, W.H.

1988-07-01

In previous studies the doubly labeled water method for measuring energy expenditure in free-living humans has been validated against respirometry under sedentary conditions. In the present investigation, energy expenditure is measured simultaneously with doubly labeled water and respirometry at low- and high-activity levels. Over 6 days, five subjects were measured doing mainly sedentary activities like desk work; their average daily metabolic rate was 1.40 +/- 0.09 (SD) times sleeping metabolic rate. Four subjects were measured twice over 3.5 days, including 2 days with heavy bicycle ergometer work, resulting in an average daily metabolic rate of 2.61 +/- 0.25 (SD) timesmore » sleeping metabolic rate. At the low-activity level, energy expenditures from the doubly labeled water method were on the average 1.4 +/- 3.9% (SD) larger than those from respirometry. At the high-activity level, the doubly labeled water method yielded values that were 1.0 +/- 7.0% (SD) lower than those from respirometry. Results demonstrate the utility of the doubly labeled water method for the determination of energy expenditure in the range of activity levels in daily life.« less

A review of limits on microbial activity in the cryosphere: temperature and water availability

NASA Astrophysics Data System (ADS)

Bakermans, C.

2017-12-01

The extent of microbial activity in the cryosphere likely depends on many things: the presence of liquid water, an adequate energy and nutrient supply (amount and flux), the absence of damaging conditions, exposure to low temperatures, and the time to evolve adaptations to low temperature conditions. Determining the extent of microbial activity in the cryosphere is a challenge complicated by the reduced availability of liquid water as water freezes and the low rates of diffusion and reaction brought on by low temperatures. Despite these limitations, many studies have demonstrated that reproduction by microorganisms is possible at temperatures of -10 to -20°C and that metabolism continues to even lower temperatures of about -30°C. In addition, microcosm studies in frozen soils and permafrost have demonstrated respiration down to temperatures of -18°C and DNA synthesis at temperatures from 0 to -20°C. In the environment, low temperature conditions (and lack of liquid water) appear to limit microbial activity in a few places like Don Juan Pond and University Valley in Antarctica. Microorganisms may be metabolically active in Arctic permafrost, but metabolism may be so exceptionally slow as to escape detection. Given the slow metabolism expected and the short geological age of permafrost (3 million years at the longest), there is probably insufficient time for microorganisms to evolve to become better adapted to live at subfreezing temperatures. Indeed, terrestrial life may never have the chance to evolve to exploit the low temperature capabilities of its biomolecules in view of the limited times at which cold environments persist on Earth. These observational studies of microorganisms in low temperature environments of the Polar regions expose how the extent of microbial activity at low temperature is entangled with other factors (perhaps inextricably); how the lack of liquid water at low temperatures appears to be the true limit on activity at low temperatures

33 CFR 151.1514 - Ballast water management alternatives under extraordinary conditions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... failure, or other extraordinary conditions, is unable to effect a ballast water exchange before entering... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Ballast water management... SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER Ballast Water Management for Control of...

33 CFR 151.1514 - Ballast water management alternatives under extraordinary conditions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... failure, or other extraordinary conditions, is unable to effect a ballast water exchange before entering... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Ballast water management... SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER Ballast Water Management for Control of...

Experimental determination of activities of FeO and Fe 2O 3 components in hydrous silicic melts under oxidizing conditions

NASA Astrophysics Data System (ADS)

Gaillard, Fabrice; Pichavant, Michel; Scaillet, Bruno

2003-11-01

The critical role of iron on crystal-silicate liquid relationships and melt differentiation is mainly controlled by the redox conditions prevailing in magmas, but the presently available database merely constrains the thermodynamic properties of iron-bearing components in strongly reduced and anhydrous molten silicate where iron is in the ferrous form. This paper provides new standard states for pure ferrous (FeOliq) and ferric (Fe2O3liq) molten iron oxides and extends the experimental database towards oxidizing and water-bearing domains. Iron-iridium, iron-platinum alloys, magnetite or hematite were equilibrated with synthetic silicic liquids at high temperature and high pressure under controlled oxygen fugacity (fO2) to determine activity-composition relationships for FeOliq and Fe2O3liq. Between 1000 and 1300°C, the fO2 ranges from that in air to 3-log units below that of the nickel-nickel oxide buffer (NNO). Experiments were performed on both anhydrous and hydrous melts containing up to 6-wt.% water. Incorporation of water under reducing conditions increases the activity coefficient of FeOliq but has an opposite effect on Fe2O3liq. As calcium is added to system, the effect of water becomes weaker and is inverted for Fe2O3liq. Under oxidizing conditions, water has a negligible effect on both activities of FeOliq and Fe2O3liq. In contrast, changes in redox conditions dominate the activity coefficients of both FeOliq and Fe2O3liq, which increase significantly with increasing fO2. The present results combined with the previous work provide a specific database on the energetics of iron in silicate melts that cover most of the condition prevailing in natural magmas.

An active dealkalization of red mud with roasting and water leaching.

PubMed

Zhu, Xiaobo; Li, Wang; Guan, Xuemao

2015-04-09

The research has focused on the dealkalization of red mud after active roasting and water leaching, which is obtained from bauxite during alumina production. The main factors such as roasting temperature, roasting time, water leaching stage, leaching temperature, leaching reaction time and liquid to solid ratio were investigated. The mechanism of dealkalization was in-depth studied by using ICP-AES, XRD, TG-DSC, SEM-EDS and leaching kinetic. The results show that the dealkalization rate reached 82% under the condition of roasting temperature of 700 °C, roasting time of 30 min, four stage water leaching, liquid to solid ratio of 7 mL/g, leaching temperature of 90 °C and reaction time of 60 min. The diffraction peak of Na6CaAl6Si6(CO3)O24 · 2H2O in red mud was decreased during the active roasting process, whereas the mineral phases of NaOH · H2O and Na2Ca(CO3)2 were appeared. The content of alkali obviously decreased and the grade of other elements increased during the process of active roasting and water leaching, which was in favor of next application process of red mud. The water leaching was controlled by internal diffusion of SCM and the apparent activation energy was 22.63 kJ/mol. Copyright © 2014 Elsevier B.V. All rights reserved.

Aqua Dynamics. Physical Conditioning through Water Exercises.

ERIC Educational Resources Information Center

President's Council on Physical Fitness and Sports, Washington, DC.

Swimming is recognized as America's most popular active sport. It is one of the best physical activities for people of all ages and for people who are physically handicapped. Vigorous water exercises can increase a person's flexibility, strength, and cardio-vascular endurance. Exercises requiring flexibility are performed more easily in water…

Conditionally Active Min-Max Limit Regulators

NASA Technical Reports Server (NTRS)

Garg, Sanjay (Inventor); May, Ryan D. (Inventor)

2017-01-01

A conditionally active limit regulator may be used to regulate the performance of engines or other limit regulated systems. A computing system may determine whether a variable to be limited is within a predetermined range of a limit value as a first condition. The computing system may also determine whether a current rate of increase or decrease of the variable to be limited is great enough that the variable will reach the limit within a predetermined period of time with no other changes as a second condition. When both conditions are true, the computing system may activate a simulated or physical limit regulator.

Applicability of rapid and on-site measured enzyme activity for surface water quality monitoring in an agricultural catchment

NASA Astrophysics Data System (ADS)

Stadler, Philipp; Farnleitner, Andreas H.; Sommer, Regina; Kumpan, Monika; Zessner, Matthias

2014-05-01

For the near real time and on-site detection of microbiological fecal pollution of water, the measurement of beta-D- Glucuronidase (GLUC) enzymatic activity has been suggested as a surrogate parameter and has been already successfully operated for water quality monitoring of ground water resources (Ryzinska-Paier et al. 2014). Due to possible short measure intervals of three hours, this method has high potential as a water quality monitoring tool. While cultivation based standard determination takes more than one working day (Cabral 2010) the potential advantage of detecting the GLUC activity is the high temporal measuring resolution. Yet, there is still a big gap of knowledge on the fecal indication capacity of GLUC (specificity, sensitivity, persistence, etc.) in relation to potential pollution sources and catchment conditions (Cabral 2010, Ryzinska-Paier et al. 2014). Furthermore surface waters are a big challenge for automated detection devices in a technical point of view due to the high sediment load during event conditions. This presentation shows results gained form two years of monitoring in an experimental catchment (HOAL) dominated by agricultural land use. Two enzymatic measurement devices are operated parallel at the catchment outlet to test the reproducibility and precision of the method. Data from continuous GLUC monitoring under both base flow and event conditions is compared with reference samples analyzed by standardized laboratory methods for fecal pollution detection (e.g. ISO 16649-1, Colilert18). It is shown that rapid enzymatic on-site GLUC determination can successfully be operated from a technical point of view for surface water quality monitoring under the observed catchment conditions. The comparison of enzyme activity with microbiological standard analytics reveals distinct differences in the dynamic of the signals during event conditions. Cabral J. P. S. (2010) "Water Microbiology. Bacterial Pathogens and Water" International Journal of

WaterWatch - Maps, graphs, and tables of current, recent, and past streamflow conditions

USGS Publications Warehouse

Jian, Xiaodong; Wolock, David; Lins, Harry F.

2008-01-01

WaterWatch (http://water.usgs.gov/waterwatch/) is a U.S. Geological Survey (USGS) World Wide Web site that dis­plays maps, graphs, and tables describing real-time, recent, and past streamflow conditions for the United States. The real-time information generally is updated on an hourly basis. WaterWatch provides streamgage-based maps that show the location of more than 3,000 long-term (30 years or more) USGS streamgages; use colors to represent streamflow conditions compared to historical streamflow; feature a point-and-click interface allowing users to retrieve graphs of stream stage (water elevation) and flow; and highlight locations where extreme hydrologic events, such as floods and droughts, are occurring.The streamgage-based maps show streamflow conditions for real-time, average daily, and 7-day average streamflow. The real-time streamflow maps highlight flood and high flow conditions. The 7-day average streamflow maps highlight below-normal and drought conditions.WaterWatch also provides hydrologic unit code (HUC) maps. HUC-based maps are derived from the streamgage-based maps and illustrate streamflow conditions in hydrologic regions. These maps show average streamflow conditions for 1-, 7-, 14-, and 28-day periods, and for monthly average streamflow; highlight regions of low flow or hydrologic drought; and provide historical runoff and streamflow conditions beginning in 1901.WaterWatch summarizes streamflow conditions in a region (state or hydrologic unit) in terms of the long-term typical condition at streamgages in the region. Summary tables are provided along with time-series plots that depict variations through time. WaterWatch also includes tables of current streamflow information and locations of flooding.

Ground-water conditions in Georgia, 1997

USGS Publications Warehouse

Cressler, A.M.

1998-01-01

Ground-water conditions in Georgia during 1997 and for the period of record were evaluated using data from ground-water-level and ground-water-quality monitoring networks. Data for 1997 included in this report are from continuous water-level records from 71 wells and chloride analyses from 14 wells. In 1997, annual mean ground-water levels in Georgia ranged from 6.2 feet (ft) lower to 5.6 ft higher than in 1996. Of the 71 wells summarized in this report, 23 wells had annual mean water levels that were higher, 35 wells had annual mean water levels that were lower, and 11 wells had annual mean water levels that were about the same in 1997 as during 1996. Data for two wells are incomplete because data collection was discontinued at one well, and the equipment was vandalized at one well. Record-low daily mean water levels were recorded in six wells tapping the Upper Floridan aquifer, one well tapping the Caliborne aquifer, two wells tapping the Clayton aquifer, and three wells tapping Cretaceous aquifers. These record lows were from 0.2 to 5.6 ft lower than previous record lows. Chloride concentration in water from the Upper Floridan aquifer in most of coastal Georgia was within drinking-water standards established by the Georgia Department of Natural Resources and the U.S. Environmental Protection Agency. In the Savannah area, chloride concentration has not changed appreciably with time. However, chloride concentration in water from some wells that tap the Floridan aquifer system in the Brunswick area exceeds the drinking-water standard. Ground-water-level and ground-water-quality data are essential for water assessment and management. Ground-water-level fluctuations and trends can be used to estimate changes in aquifer storage resulting from the effects of ground-water withdrawal and recharge from precipitation. These data can be used to address water-management needs and to evaluate the effects of management and conservation programs. As part of the ground-water

Selective effect of myclobutanil enantiomers on fungicidal activity and fumonisin production by Fusarium verticillioides under different environmental conditions.

PubMed

Li, Na; Deng, Luqing; Li, Jianfang; Wang, Zhengbing; Han, Yiye; Liu, Chenglan

2018-05-01

Myclobutanil is a widely used triazole fungicide, comprising two enantiomers with different fungicidal activities, non-target toxicities, and environmental fates. The enantioselective effects of myclobutanil on fumonisin B (FB) production by Fusarium verticillioides, an important pathogen, have not yet been investigated. In the present study, the fungicidal activities of rac-myclobutanil and its enantiomers on F. verticillioides cultured on maize-based media were studied under different water activity and temperature conditions. The FB levels were measured to assess the enantioselective effects on FB production when F. verticillioides were cultured treated with EC 50 and EC 90 concentrations (concentrations inhibiting mycelial growth by 50.0% and 90.0%, respectively) of myclobutanil and enantiomers under different conditions. The fungicidal activities of rac-myclobutanil and its enantiomers decreased with increasing temperature and decreasing water activity. Little difference in fungicidal activity was observed between the enantiomers. FB production was significantly influenced by temperature, a w , and fungicides dose. At EC50 concentrations, rac-myclobutantil and its enantiomers were shown to enhance mycotoxin production and enantioselective effects of enantiomers on FB production were observed under certain conditions. This is the first report on the differential effects of myclobutanil enantiomers on the control of F. verticillioides growth and FB production in maize-based media under different conditions. Copyright © 2018 Elsevier Inc. All rights reserved.

Aluminum/water reactions under extreme conditions

NASA Astrophysics Data System (ADS)

Hooper, Joseph

2013-03-01

We discuss mechanisms that may control the reaction of aluminum and water under extreme conditions. We are particularly interested in the high-temperature, high-strain regime where the native oxide layer is destroyed and fresh aluminum is initially in direct contact with liquid or supercritical water. Disparate experimental data over the years have suggested rapid oxidation of aluminum is possible in such situations, but no coherent picture has emerged as to the basic oxidation mechanism or the physical processes that govern the extent of reaction. We present theoretical and computational analysis of traditional metal/water reaction mechanisms that treat diffusion through a dynamic oxide layer or reaction limited by surface kinetics. Diffusion through a fresh solid oxide layer is shown to be far too slow to have any effect on the millisecond timescale (even at high temperatures). Quantum molecular dynamics simulations of liquid Al and water surface reactions show rapid water decomposition at the interface, catalyzed by adjacent water molecules in a Grotthus-like relay mechanism. The surface reaction barriers are far too low for this to be rate-limiting in any way. With these straightforward mechanisms ruled out, we investigate two more complex possibilities for the rate-limiting factor; first, we explore the possibility that newly formed oxide remains a metastable liquid well below its freezing point, allowing for diffusion-limited reactions through the oxide shell but on a much faster timescale. The extent of reaction would then be controlled by the solidification kinetics of alumina. Second, we discuss preliminary analysis on surface erosion and turbulent mixing, which may play a prominent role during hypervelocity penetration of solid aluminum projectiles into water.

Declarative virtual water maze learning and emotional fear conditioning in primary insomnia.

PubMed

Kuhn, Marion; Hertenstein, Elisabeth; Feige, Bernd; Landmann, Nina; Spiegelhalder, Kai; Baglioni, Chiara; Hemmerling, Johanna; Durand, Diana; Frase, Lukas; Klöppel, Stefan; Riemann, Dieter; Nissen, Christoph

2018-05-02

Healthy sleep restores the brain's ability to adapt to novel input through memory formation based on activity-dependent refinements of the strength of neural transmission across synapses (synaptic plasticity). In line with this framework, patients with primary insomnia often report subjective memory impairment. However, investigations of memory performance did not produce conclusive results. The aim of this study was to further investigate memory performance in patients with primary insomnia in comparison to healthy controls, using two well-characterized learning tasks, a declarative virtual water maze task and emotional fear conditioning. Twenty patients with primary insomnia according to DSM-IV criteria (17 females, three males, 43.5 ± 13.0 years) and 20 good sleeper controls (17 females, three males, 41.7 ± 12.8 years) were investigated in a parallel-group study. All participants completed a hippocampus-dependent virtual Morris water maze task and amygdala-dependent classical fear conditioning. Patients with insomnia showed significantly delayed memory acquisition in the virtual water maze task, but no significant difference in fear acquisition compared with controls. These findings are consistent with the notion that memory processes that emerge from synaptic refinements in a hippocampal-neocortical network are particularly sensitive to chronic disruptions of sleep, while those in a basic emotional amygdala-dependent network may be more resilient. © 2018 European Sleep Research Society.

Quality-Assurance Plan for Water-Quality Activities in the USGS Ohio Water Science Center

USGS Publications Warehouse

Francy, Donna S.; Shaffer, Kimberly H.

2008-01-01

In accordance with guidelines set forth by the Office of Water Quality in the Water Resources Discipline of the U.S. Geological Survey, a quality-assurance plan has been written for use by the Ohio Water Science Center in conducting water-quality activities. This quality-assurance plan documents the standards, policies, and procedures used by the Ohio Water Science Center for activities related to the collection, processing, storage, analysis, and publication of water-quality data. The policies and procedures documented in this quality-assurance plan for water-quality activities are meant to complement the Ohio Water Science Center quality-assurance plans for water-quality monitors, the microbiology laboratory, and surface-water and ground-water activities.

Water conditioning and whooping crane survival after release in Florida

USGS Publications Warehouse

Gee, G.F.; Nicolich, Jane M.; Nesbitt, S.A.; Hatfield, J.S.; Ellis, D.H.; Olsen, Glenn H.

2001-01-01

About 50% of the whooping cranes (Grus americana) released in Florida die within the first year of release. Most of these deaths and those in subsequent years result from bobcat (Lynx rufus) predation. Choosing release sites in open marshes away from bobcat habitat has improved survival. We hypothesized that exposure to ponds (water conditioning) at the rearing site would encourage birds to roost in deeper water marshes after release and such exposure would thereby reduce bobcat predation. In this study, we moved young birds (ca 50 days of age) to netted pens with large (15-m diameter), deep 30-60 cm) naturally vegetated ponds. We randomly assigned the costume-reared whooping cranes into 2 equal-sized groups at fledging. Some groups were placed in pens with a pond (experimental or ponded groups) and the others we reared without additional water exposure (control groups). All birds in the pens with ponds used the water. At night, they roosted at a depth of 36-46 cm. During the day, the birds used the ponds as well as other areas of the pen. We released 3 pairs of water-conditioned and control cohorts, 1 set in 1995 and 2 in 1996. No obvious behavioral differences were noted between the cohorts released in those years. Controls survived as expected (about 60% first year survival). The water-conditioned birds had much higher survival the first year (85%) and continued to survive better for the next 3 years.

Determination of beta activity in water

USGS Publications Warehouse

Barker, F.B.; Robinson, B.P.

1963-01-01

Many elements have one or more naturally radioactive isotopes, and several hundred other radionuclides have been produced artificially. Radioactive substances may be present in natural water as a result of geochemical processes or the release of radioactive waste and other nuclear debris to the environment. The Geological Survey has developed methods for measuring certain of these .radioactive substances in water. Radioactive substances often are present in water samples in microgram quantities or less. Therefore, precautions must be taken to prevent loss of material and to assure that the sample truly represents its source at the time of collection. Addition of acids, complexing agents, or stable isotopes often aids in preventing loss of radioactivity on container walls, on sediment, or on other solid materials in contact with the sample. The disintegration of radioactive atoms is a random process subject to established methods of statistical analysis. Because many water samples contain small amounts of radioactivity, low-level counting techniques must be used. The usual assumption that counting data follow a Gaussian distribution is invalid under these conditions, and statistical analyses must be based on the Poisson distribution. The gross beta activity in water samples is determined from the residue left after evaporation of the sample to dryness. Evaporation is accomplished first in a teflon dish, then the residue is transferred with distilled water to a counting planchet and again is reduced to dryness. The radioactivity on the planchet is measured with an anticoincidence-shielded, low-background, beta counter and is compared with measurements of a strontium-90-yttrium-90 standard prepared and measured in the same manner. Control charts are used to assure consistent operation of the counting instrument.

Bridge pressure flow scour for clear water conditions

DOT National Transportation Integrated Search

2009-10-01

The equilibrium scour at a bridge caused by pressure flow with critical approach velocity in clear-water simulation conditions was studied both analytically and experimentally. The flume experiments revealed that (1) the measured equilibrium scour pr...

Modelling of the Water Exchange between Shallow Groundwater and River during bank filtration and changing conditions

NASA Astrophysics Data System (ADS)

Wang, Weishi; Munz, Matthias; Oswald, Sascha E.

2015-04-01

The interaction of river water and groundwater is of importance for the hydrological cycle and water quality in rivers. Moreover, drinking water is often obtained by pumping groundwater in the direct vicinity of rivers, called bank filtration. Typically this implies a considerable dynamics, because changes in river water level and pumping activities will cause varying conditions, and in its effects modified by the local hydrogeology. Numerical modelling can be a tool to study spatial patterns and temporal changes. Often this is limited by model performance, uncertainty of geological structure and lack of sufficient observation values beyond water heads, for example water quality or temperature data. The aim of this research is to model the hydraulic conditions for transient conditions, including a period of substantial re-construction works in the river. Later this will then be used to include the temperature and other water quality data to improve the model performance. As shown from the geological information analysis, the majority of the water volume pumped is from the first and second aquifers, where a strong exchange between the river and groundwater can happen. The implementation of the geological structure is based on 7 main geological profiles and several scattered drilling wells of difference depths. A first model has been built in FEFLOW 6.2 as a steady fluid flow model, while the pilot-points auto-calibration method is used for estimating the hydraulic conductivity of different sediment types, based on water head information of 19 observation wells. Then a transient model during the year 2011-2013 is further calibrated based on estimated hydraulic conductivity. Furthermore, the observation wells are used to make a statistic analysis with the hydrograph of the river to clarify the correlation of changes in river to changes in groundwater.

AFM Structural Characterization of Drinking Water Biofilm under Physiological Conditions

EPA Science Inventory

Due to the complexity of mixed culture drinking water biofilm, direct visual observation under in situ conditions has been challenging. In this study, atomic force microscopy (AFM) revealed the three dimensional morphology and arrangement of drinking water relevant biofilm in air...

WATER: Water Activities Teaching Environmental Responsibility: Teacher Resource, Environmental Science.

ERIC Educational Resources Information Center

Kramer, Ed, Ed.; And Others

This activity book was developed as part of an effort to protect water quality of the Stillwater River, Ohio, through a Watershed Protection Project. It is designed to raise teachers' and students' awareness and trigger a sense of stewardship towards the preservation of water resources. The activities are generally appropriate for elementary age…

GEO Water Cycle Activities and Plans

NASA Astrophysics Data System (ADS)

Lawford, R.; Koike, T.; Ishida, C.; Grabs, W.

2008-12-01

The Group on Earth Observations (GEO) consists of more than 70 countries and 40 international organizations which are working together to develop the Global Earth Observation System of Systems (GEOSS). Since its launch in 2004, GEO has stimulated a wide range of activities related to data systems and their architecture, the development of science and technology to support observational programs, user interactions and interfaces, and capacity building. GEO tasks directed at Water Resources Management, one of the nine GEO Societal Benefit areas, are an integral part of these developments. They draw heavily upon the activities of the Integrated Global Water Cycle Observations (IGWCO) theme and on the activities and infrastructure provided through GEO and its committees. Within the GEO framework the water related activities have been focused on four specific tasks namely integrated data set development; information for floods, droughts and water management; water quality, and capacity building. Currently these efforts are being facilitated by the IGWCO theme that was formed under the former Integrated Global Observing Strategy Partnership (IGOS-P). With the dissolution of this partnership, other mechanisms, including the GEO Water Cycle Community of Practice, are being considered as new opportunitites for coordinating the work of the theme and the water-related GEO tasks. This talk provides a description of the GEO water tasks and reviews the progress that has been made in addressing them. It also provides a perspective on new opportunities and briefly describes some of the mechanisms, such as the Water Cycle Community of Practice, that could be expanded to coordinate a more comprehensive set of water tasks and greater community involvement.

Demonstration of the Tilting of the Gas-Water Interface under Hydrodynamic Conditions.

ERIC Educational Resources Information Center

Gretener, P. E.

1979-01-01

Describes the construction of an apparatus to demonstrate the tilting of an oil-water, gas-water, or gas-oil interface when the subsurface reservoir is under hydrodynamic conditions (i.e., when conditions of lateral flow exist). The model can be constructed of readily-available materials. (RE)

Active microwave water equivalence

NASA Technical Reports Server (NTRS)

Boyne, H. S.; Ellerbruch, D. A.

1980-01-01

Measurements of water equivalence using an active FM-CW microwave system were conducted over the past three years at various sites in Colorado, Wyoming, and California. The measurement method is described. Measurements of water equivalence and stratigraphy are compared with ground truth. A comparison of microwave, federal sampler, and snow pillow measurements at three sites in Colorado is described.

LCA of waste prevention activities: a case study for drinking water in Italy.

PubMed

Nessi, Simone; Rigamonti, Lucia; Grosso, Mario

2012-10-15

The strategic relevance of waste prevention has considerably increased worldwide during recent years, such that the current European legislation requires the preparation of national waste prevention programmes in which reduction objectives and measures are identified. In such a context, it is possible to recognise how, in order to correctly evaluate the environmental consequences of a prevention activity, a life cycle perspective should be employed. This allows us to go beyond the simple reduction of the generated waste which, alone, does not automatically imply achieving better overall environmental performance, especially when this reduction is not pursued through the simple reduction of consumption. In this study, the energetic and environmental performance of two waste prevention activities considered particularly meaningful for the Italian context were evaluated using life cycle assessment (LCA) methodology. The two activities were the utilisation of public network water (two scenarios) and of refillable bottled water (two scenarios) for drinking purposes, instead of one-way bottled water (three scenarios). The energy demand and specific potential impacts of the four waste prevention scenarios and of the three baseline scenarios were compared with the aim of evaluating whether, and under what conditions, the analysed prevention activities are actually associated with overall energetic and environmental benefits. In typical conditions, the use of public network water directly from the tap results in the best scenario, while if water is withdrawn from public fountains, its further transportation by private car can involve significant impacts. The use of refillable PET bottled water seems the preferable scenario for packaged water consumption, if refillable bottles are transported to local distributors along the same (or a lower) distance as one-way bottles to retailers. The use of refillable glass bottled water is preferable to one-way bottled water only if a

Evaluation of bioaugmentation efficiency for the treatment of run-off water under tropical conditions: applications to the Derby-Tacaruna canal (Recife/Brazil).

PubMed

da Silva, M C L; Nascimento, A M; da Silva, V L; Pons, M N; da Motta, M

2009-01-01

An evaluation of the efficiency of bacterial biomass augmentation was performed at lab-scale for the pollution treatment of the Derby-Tacaruna canal. The canal is located at the central area of Great Recife, alongside an important urban corridor. The characterization of the canal water in different tidal conditions showed that the actual pollution is organic and inorganic (heavy metals). Degradation experiments of water from the canal and rain-off system polluted by synthetic wastewater were performed, using activated sludge and an industrial bioadditive. Continuous reactors under two different conditions were evaluated: with diffuse aeration and without aeration. The channel reactor was operated under steady state conditions at a flow rate of 2.5 L h(-1) and with an average residence time of 22 h without aeration and 17 h with aeration. The organic matter removal was in the range of 60% for the system inoculated with the bioadditive and 85% with activated sludge. It was concluded that the water of the Derby-Tacaruna canal may be treated by activated sludge without being affected by its salt content, while the bioaugmentation technique was not satisfactory due to inhibition by inorganics.

Removal of calcium and magnesium ions from shale gas flowback water by chemically activated zeolite.

PubMed

Chang, Haiqing; Liu, Teng; He, Qiping; Li, Duo; Crittenden, John; Liu, Baicang

2017-07-01

Shale gas has become a new sweet spot of global oil and gas exploration, and the large amount of flowback water produced during shale gas extraction is attracting increased attention. Internal recycling of flowback water for future hydraulic fracturing is currently the most effective, and it is necessary to decrease the content of divalent cations for eliminating scaling and maintaining effectiveness of friction reducer. Zeolite has been widely used as a sorbent to remove cations from wastewater. This work was carried out to investigate the effects of zeolite type, zeolite form, activation chemical, activation condition, and sorption condition on removal of Ca 2+ and Mg 2+ from shale gas flowback water. Results showed that low removal of Ca 2+ and Mg 2+ was found for raw zeolite 4A and zeolite 13X, and the efficiency of the mixture of both zeolites was slightly higher. Compared with the raw zeolites, the zeolites after activation using NaOH and NaCl greatly improved the sorption performance, and there was no significant difference between dynamic activation and static activation. Dynamic sorption outperformed static sorption, the difference exceeding 40% and 7-70% for removal of Ca 2+ and Mg 2+ , respectively. Moreover, powdered zeolites outperformed granulated zeolites in divalent cation removal.

Removal of benzocaine from water by filtration with activated carbon

USGS Publications Warehouse

Howe, G.E.; Bills, T.D.; Marking, L.L.

1990-01-01

Benzocaine is a promising candidate for registration with the U.S. Food and Drug Administration for use as an anesthetic in fish culture, management, and research. A method for the removal of benzocaine from hatchery effluents could speed registration of this drug by eliminating requirements for data on its residues, tolerances, detoxification, and environmental hazards. Carbon filtration effectively removes many organic compounds from water. This study tested the effectiveness of three types of activated carbon for removing benzocaine from water by column filtration under controlled laboratory conditions. An adsorptive capacity was calculated for each type of activated carbon. Filtrasorb 400 (12 x 40 mesh; U.S. standard sieve series) showed the greatest capacity for benzocaine adsorption (76.12 mg benzocaine/g carbon); Filtrasorb 300 (8 x 30 mesh) ranked next (31.93 mg/g); and Filtrasorb 816 (8 x 16 mesh) absorbed the least (1.0 mg/g). Increased adsorptive capacity was associated with smaller carbon particle size; however, smaller particle size also impeded column flow. Carbon filtration is a practical means for removing benzocaine from treated water.

In-pipe water quality monitoring in water supply systems under steady and unsteady state flow conditions: a quantitative assessment.

PubMed

Aisopou, Angeliki; Stoianov, Ivan; Graham, Nigel J D

2012-01-01

Monitoring the quality of drinking water from the treatment plant to the consumers tap is critical to ensure compliance with national standards and/or WHO guideline levels. There are a number of processes and factors affecting the water quality during transmission and distribution which are little understood. A significant obstacle for gaining a detailed knowledge of various physical and chemical processes and the effect of the hydraulic conditions on the water quality deterioration within water supply systems is the lack of reliable and low-cost (both capital and O & M) water quality sensors for continuous monitoring. This paper has two objectives. The first one is to present a detailed evaluation of the performance of a novel in-pipe multi-parameter sensor probe for reagent- and membrane-free continuous water quality monitoring in water supply systems. The second objective is to describe the results from experimental research which was conducted to acquire continuous water quality and high-frequency hydraulic data for the quantitative assessment of the water quality changes occurring under steady and unsteady-state flow conditions. The laboratory and field evaluation of the multi-parameter sensor probe showed that the sensors have a rapid dynamic response, average repeatability and unreliable accuracy. The uncertainties in the sensor data present significant challenges for the analysis and interpretation of the acquired data and their use for water quality modelling, decision support and control in operational systems. Notwithstanding these uncertainties, the unique data sets acquired from transmission and distribution systems demonstrated the deleterious effect of unsteady state flow conditions on various water quality parameters. These studies demonstrate: (i) the significant impact of the unsteady-state hydraulic conditions on the disinfectant residual, turbidity and colour caused by the re-suspension of sediments, scouring of biofilms and tubercles from the

The Influence Of Variability Of Water Resources In Lowland Forests On Selected Parameters Describing The Condition Of Trees

NASA Astrophysics Data System (ADS)

Tyszka, Jan; Stolarek, Andrzej; Fronczak, Ewa

2014-01-01

into the rooting zone of trees there were even twofold differences in measured growth increments in Scots pine (as the dominant species in Poland's lowland habitats). The maintenance of stable water conditions (as the most variable environmental factor in forest) should be an overriding aim of management activity in this habitat. When account is taken of the influence of the state of water resources on biomass production, and then on the intensity of evapotranspiration and the absorption of carbon dioxide from the atmosphere, it is seen how important it is to achieve improvements in water conditions in forests, as such an important factor in combating climate change.

Methane excess production in oxygen-rich polar water and a model of cellular conditions for this paradox

NASA Astrophysics Data System (ADS)

Damm, E.; Thoms, S.; Beszczynska-Möller, A.; Nöthig, E. M.; Kattner, G.

2015-09-01

Summer sea ice cover in the Arctic Ocean has undergone a reduction in the last decade exposing the sea surface to unforeseen environmental changes. Melting sea ice increases water stratification and induces nutrient limitation, which is also known to play a crucial role in methane formation in oxygenated surface water. We report on an excess of methane in the marginal ice zone in the western Fram Strait. Our study is based on measurements of oxygen, methane, DMSP, nitrate and phosphate concentrations as well as on phytoplankton composition and light transmission, conducted along the 79°N oceanographic transect, in the western part of the Fram Strait and in Northeast Water Polynya region off Greenland. Between the eastern Fram Strait, where Atlantic water enters from the south and the western Fram Strait, where Polar water enters from the north, different nutrient limitations occurred and consequently different bloom conditions were established. Ongoing sea ice melting enhances the environmental differences between both water masses and initiates regenerated production in the western Fram Strait. We show that in this region methane is in situ produced while DMSP (dimethylsulfoniopropionate) released from sea ice may serve as a precursor for the methane formation. The methane production occured despite high oxygen concentrations in this water masses. As the metabolic activity (respiration) of unicellular organisms explains the presence of anaerobic conditions in the cellular environment we present a theoretical model which explains the maintenance of anaerobic conditions for methane formation inside bacterial cells, despite enhanced oxygen concentrations in the environment.

[Spectrum Variance Analysis of Tree Leaves Under the Condition of Different Leaf water Content].

PubMed

Wu, Jian; Chen, Tai-sheng; Pan, Li-xin

2015-07-01

Leaf water content is an important factor affecting tree spectral characteristics. So Exploring the leaf spectral characteristics change rule of the same tree under the condition of different leaf water content and the spectral differences of different tree leaves under the condition of the same leaf water content are not only the keys of hyperspectral vegetation remote sensing information identification but also the theoretical support of research on vegetation spectrum change as the differences in leaf water content. The spectrometer was used to observe six species of tree leaves, and the reflectivity and first order differential spectrum of different leaf water content were obtained. Then, the spectral characteristics of each tree species leaves under the condition of different leaf water content were analyzed, and the spectral differences of different tree species leaves under the condition of the same leaf water content were compared to explore possible bands of the leaf water content identification by hyperspectral remote sensing. Results show that the spectra of each tree leaf have changed a lot with the change of the leaf water content, but the change laws are different. Leaf spectral of different tree species has lager differences in some wavelength range under the condition of same leaf water content, and it provides some possibility for high precision identification of tree species.

Antibacterial Activity of Polyphenols: Structure-Activity Relationship and Influence of Hyperglycemic Condition.

PubMed

Xie, Yixi; Chen, Jing; Xiao, Aiping; Liu, Liangliang

2017-11-06

Polyphenols are plant-derived natural products with well-documented health benefits to human beings, such as antibacterial activities. However, the antibacterial activities of polyphenols under hyperglycemic conditions have been rarely studied, which could be relevant to their antibacterial efficacy in disease conditions, such as in diabetic patients. Herein, the antibacterial activities of 38 polyphenols under mimicked hyperglycemic conditions were evaluated. The structure-antibacterial activity relationships of polyphenols were also tested and analyzed. The presence of glucose apparently promoted the growth of the bacterial strains tested in this study. The OD600 values of tested bacteria strains increased from 1.09-fold to 1.49-fold by adding 800 mg/dL glucose. The polyphenols showed structurally dependent antibacterial activities, which were significantly impaired under the hyperglycemic conditions. The results from this study indicated that high blood glucose might promote bacterial infection, and the hyperglycemic conditions resulting from diabetes were likely to suppress the antibacterial benefits of polyphenols.

ORGANOPHOSPHATE PESTICIDE DEGRADATION UNDER DRINKING WATER TREATMENT CONDITIONS

EPA Science Inventory

Chlorpyrifos (CP) was used as a model compound to develop experimental methods and prototype modeling tools to forecast the fate of organophosphate (OP) pesticides under drinking water treatment conditions. CP was found to rapidly oxidize to chlorpyrifos oxon (CPO) in the presen...

Ground-water conditions in southern Utah Valley and Goshen Valley, Utah

USGS Publications Warehouse

Cordova, R.M.

1970-01-01

The investigation of ground-water conditions in southern Utah Valley and Goshen Valley, Utah, was made by the U. S. Geological Survey as part of a cooperative program with the Utah Department of Natural Resources, Division of Water Rights, to investigate the water resources of the State. The purposes of the investigation were to (1) determine the occurrence, recharge, discharge, movement, storage, chemical quality, and availability of ground water; (2) appraise the effects of increased withdrawal of water from wells; and (3) evaluate the effect of the Central Utah Project on the ground-water reservoir and the water supply of Utah Lake.This report presents a description of the aquifer system in the two valleys, a detailed description of the ground-water resources, and conclusions about potential development and its effect on the hydrologic conditions in the valleys. Two supplementary reports are products of the investigation. A basic-data release (Cordova, 1969) contains most of the basic data collected for the investigation, including well characteristics, drillers' logs, water levels, pumpage from wells, chemical analyses of ground and surface waters, and discharge of selected springs, drains, and streams. An interpretive report (Cordova and Mower, 1967) contains the results of a large-scale aquifer test in southern Utah Valley.

Arbuscular mycorrhizal symbiosis increases relative apoplastic water flow in roots of the host plant under both well-watered and drought stress conditions.

PubMed

Bárzana, Gloria; Aroca, Ricardo; Paz, José Antonio; Chaumont, François; Martinez-Ballesta, Mari Carmen; Carvajal, Micaela; Ruiz-Lozano, Juan Manuel

2012-04-01

The movement of water through mycorrhizal fungal tissues and between the fungus and roots is little understood. It has been demonstrated that arbuscular mycorrhizal (AM) symbiosis regulates root hydraulic properties, including root hydraulic conductivity. However, it is not clear whether this effect is due to a regulation of root aquaporins (cell-to-cell pathway) or to enhanced apoplastic water flow. Here we measured the relative contributions of the apoplastic versus the cell-to-cell pathway for water movement in roots of AM and non-AM plants. We used a combination of two experiments using the apoplastic tracer dye light green SF yellowish and sodium azide as an inhibitor of aquaporin activity. Plant water and physiological status, root hydraulic conductivity and apoplastic water flow were measured. Roots of AM plants enhanced significantly relative apoplastic water flow as compared with non-AM plants and this increase was evident under both well-watered and drought stress conditions. The presence of the AM fungus in the roots of the host plants was able to modulate the switching between apoplastic and cell-to-cell water transport pathways. The ability of AM plants to switch between water transport pathways could allow a higher flexibility in the response of these plants to water shortage according to the demand from the shoot.

Aspergillus penicillioides differentiation and cell division at 0.585 water activity.

PubMed

Stevenson, Andrew; Hamill, Philip G; O'Kane, Callum J; Kminek, Gerhard; Rummel, John D; Voytek, Mary A; Dijksterhuis, Jan; Hallsworth, John E

2017-02-01

Water availability acts as the most stringent constraint for life on Earth. Thus, understanding the water relations of microbial extremophiles is imperative to our ability to increase agricultural productivity (e.g., by enhancing the processing and turnover of dead organic matter in soils of arid regions), reduce human exposure to mycotoxins in buildings and our food-supply chain, prevent the spoilage of foods/animal feeds, books, museum specimens and artworks and better control microbiology of industrial fermentations. Only a small number of microbial systems can retain activity at <0.710 water activity (ISME J 2015 9: 1333-1351). It has long-been considered that the most resilient of these is Xeromyces bisporus, which inhabits sugar-rich substrates (Appl Environ Microbiol 1968 16: 1853-1858). The current study focused on germination of Aspergillus penicillioides, a xerophile which is also able to grow under low humidity and saline conditions. Investigations of germination differed from those reported earlier: firstly, aerially borne conidia were harvested, and then used for inoculations, in their dry condition; secondly, cultures were incubated at 24°C, i.e. below optimum germination temperature, to minimize the possibility of water loss from the substrate; thirdly, cultures remained sealed throughout the 73-day study period (microscopic examination was carried out directly 48 through the Petri plate lid); fourthly, the germination parameters determined were: rates and extent of conidial swelling, production of differentiated germination-structures and septate germlings, and subsequent development of mycelium and/or sporulation; fifthly, assessments were carried out over a range of water-activity values and time points to obtain a complete profile of the germination process. Conidia swelled, formed differentiated germination-structures and then produced septate germlings at a water-activity of just 0.585 (≡58.5% relative humidity), outside the currently

Variations in water status, gas exchange, and growth in Rosmarinus officinalis plants infected with Glomus deserticola under drought conditions.

PubMed

Sánchez-Blanco, Ma Jesús; Ferrández, Trinitario; Morales, Ma Angeles; Morte, Asunción; Alarcón, Juan José

2004-06-01

The influence of the arbuscular mycorrhizal fungus Glomus deserticola on the water relations, gas exchange parameters, and vegetative growth of Rosmarinus officinalis plants under water stress was studied. Plants were grown with and without the mycorrhizal fungus under glasshouse conditions and subjected to water stress by withholding irrigation water for 14 days. Along the experimental period, a significant effect of the fungus on the plant growth was observed, and under water stress, mycorrhizal plants showed an increase in aerial and root biomass compared to non-mycorrhizal plants. The decrease in the soil water potential generated a decrease in leaf water potential (psi(l)) and stem water potential (psi(x)) of mycorrhizal and non-mycorrhizal plants, with this decrease being lower in mycorrhizal water-stressed plants. Mycorrhization also had positive effects on the root hydraulic conductivity (Lp) of water stressed plants. Furthermore, mycorrhizal-stressed plants showed a more important decrease in osmotic potential at full turgor (psi(os)) than did non-mycorrhizal-stressed plants, indicating the capacity of osmotic adjustment. Mycorrhizal infection also improved photosynthetic activity (Pn) and stomatal conductance (g(s)) in plants under water stress compared to the non-mycorrhizal-stressed plants. A similar behaviour was observed in the photochemical efficiency of PSII (Fv/Fm) with this parameter being lower in non-mycorrhizal plants than in mycorrhizal plants under water stress conditions. In the same way, under water restriction, mycorrhizal plants showed higher values of chlorophyll content than did non-mycorrhizal plants. Thus, the results obtained indicated that the mycorrhizal symbiosis had a beneficial effect on the water status and growth of Rosmarinus officinalis plants under water-stress conditions.

Diclofenac removal from water with ozone and activated carbon.

PubMed

Beltrán, Fernando J; Pocostales, Pablo; Alvarez, Pedro; Oropesa, Ana

2009-04-30

Diclofenac (DCF) has been treated in water with ozone in the presence of various activated carbons. Activated carbon-free ozonation or single ozonation leads to a complete degradation of DCF in less than 15 min while in the presence of activated carbons higher degradation rates of TOC and DCF are noticeably achieved. Among the activated carbons used, P110 Hydraffin was found the most suitable for the catalytic ozonation of DCF. The influence of pH was also investigated. In the case of the single ozonation the increasing pH slightly increases the TOC removal rate. This effect, however, was not so clear in the presence of activated carbons where the influence of the adsorption process must be considered. Ecotoxicity experiments were performed, pointing out that single ozonation reduces the toxicity of the contaminated water but catalytic ozonation improved those results. As far as kinetics is concerned, DCF is removed with ozone in a fast kinetic regime and activated carbon merely acts as a simple adsorbent. However, for TOC removal the ozonation kinetic regime becomes slow. In the absence of the adsorbent, the apparent rate constant of the mineralization process was determined at different pH values. On the other hand, determination of the rate constant of the catalytic reaction over the activated carbon was not possible due to the effect of mass transfer resistances that controlled the process rate at the conditions investigated.

Characterization of the adaptive response of grapevine (cv. Tempranillo) to UV-B radiation under water deficit conditions.

PubMed

Martínez-Lüscher, J; Morales, F; Delrot, S; Sánchez-Díaz, M; Gomès, E; Aguirreolea, J; Pascual, I

2015-03-01

This work aims to characterize the physiological response of grapevine (Vitis vinifera L.) cv. Tempranillo to UV-B radiation under water deficit conditions. Grapevine fruit-bearing cuttings were exposed to three levels of supplemental biologically effective UV-B radiation (0, 5.98 and 9.66kJm(-2)day(-1)) and two water regimes (well watered and water deficit), in a factorial design, from fruit-set to maturity under glasshouse-controlled conditions. UV-B induced a transient decrease in net photosynthesis (Anet), actual and maximum potential efficiency of photosystem II, particularly on well watered plants. Methanol extractable UV-B absorbing compounds (MEUVAC) concentration and superoxide dismutase activity increased with UV-B. Water deficit effected decrease in Anet and stomatal conductance, and did not change non-photochemical quenching and the de-epoxidation state of xanthophylls, dark respiration and photorespiration being alternative ways to dissipate the excess of energy. Little interactive effects between UV-B and drought were detected on photosynthesis performance, where the impact of UV-B was overshadowed by the effects of water deficit. Grape berry ripening was strongly delayed when UV-B and water deficit were applied in combination. In summary, deficit irrigation did not modify the adaptive response of grapevine to UV-B, through the accumulation of MEUVAC. However, combined treatments caused additive effects on berry ripening. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Chemically activated carbon from lignocellulosic wastes for heavy metal wastewater remediation: Effect of activation conditions.

PubMed

Nayak, Arunima; Bhushan, Brij; Gupta, Vartika; Sharma, P

2017-05-01

Chemical activation is known to induce specific surface features of porosity and functionality which play a definite role in enhancing the adsorptive potential of the developed activated carbons. Different conditions of temperature, time, reagent type and impregnation ratio were applied on sawdust precursor and their effect on the physical, surface chemical features and finally on the adsorption potential of the developed activated carbons were analysed. Under activation conditions of 600°C, 1hr, 1:0.5 ratio, ZnCl 2 impregnated carbon (CASD_ZnCl 2 ) resulted in microporosity while KOH impregnation (CASD_KOH) yielded a carbon having a wider pore size distribution. The surface chemistry revealed similar functionalities. At same pH, temperature and adsorbate concentrations, CASD_KOH demonstrated better adsorption potential (1.06mmoles/g for Cd 2+ and 1.61mmoles/g for Ni 2+ ) in comparison to CASD_ZnCl 2 (0.23mmoles/g and 0.33mmoles/g for Cd 2+ and Ni 2+ respectively). Other features were a short equilibrium time of 60mins and an adsorbent dose of 0.2g/L for the CASD_KOH in comparison to CASD_ZnCl 2 (equilibrium time of 150min and dosage of 0.5g/L). The nature of interactions was physical for both adsorbents and pore diffusion mechanisms were operative. The results reveal the potentiality of chemical activation so as to achieve the best physico-chemical properties suited for energy efficient, economical and eco-friendly water treatment. Copyright © 2017 Elsevier Inc. All rights reserved.

Changes in complex spike activity during classical conditioning

PubMed Central

Rasmussen, Anders; Jirenhed, Dan-Anders; Wetmore, Daniel Z.; Hesslow, Germund

2014-01-01

The cerebellar cortex is necessary for adaptively timed conditioned responses (CRs) in eyeblink conditioning. During conditioning, Purkinje cells acquire pause responses or “Purkinje cell CRs” to the conditioned stimuli (CS), resulting in disinhibition of the cerebellar nuclei (CN), allowing them to activate motor nuclei that control eyeblinks. This disinhibition also causes inhibition of the inferior olive (IO), via the nucleo-olivary pathway (N-O). Activation of the IO, which relays the unconditional stimulus (US) to the cortex, elicits characteristic complex spikes in Purkinje cells. Although Purkinje cell activity, as well as stimulation of the CN, is known to influence IO activity, much remains to be learned about the way that learned changes in simple spike firing affects the IO. In the present study, we analyzed changes in simple and complex spike firing, in extracellular Purkinje cell records, from the C3 zone, in decerebrate ferrets undergoing training in a conditioning paradigm. In agreement with the N-O feedback hypothesis, acquisition resulted in a gradual decrease in complex spike activity during the conditioned stimulus, with a delay that is consistent with the long N-O latency. Also supporting the feedback hypothesis, training with a short interstimulus interval (ISI), which does not lead to acquisition of a Purkinje cell CR, did not cause a suppression of complex spike activity. In contrast, observations that extinction did not lead to a recovery in complex spike activity and the irregular patterns of simple and complex spike activity after the conditioned stimulus are less conclusive. PMID:25140129

Normal streamflows and water levels continue—Summary of hydrologic conditions in Georgia, 2014

USGS Publications Warehouse

Knaak, Andrew E.; Ankcorn, Paul D.; Peck, Michael F.

2016-03-31

The U.S. Geological Survey (USGS) South Atlantic Water Science Center (SAWSC) Georgia office, in cooperation with local, State, and other Federal agencies, maintains a long-term hydrologic monitoring network of more than 350 real-time, continuous-record, streamflow-gaging stations (streamgages). The network includes 14 real-time lake-level monitoring stations, 72 real-time surface-water-quality monitors, and several water-quality sampling programs. Additionally, the SAWSC Georgia office operates more than 204 groundwater monitoring wells, 39 of which are real-time. The wide-ranging coverage of streamflow, reservoir, and groundwater monitoring sites allows for a comprehensive view of hydrologic conditions across the State. One of the many benefits this monitoring network provides is a spatially distributed overview of the hydrologic conditions of creeks, rivers, reservoirs, and aquifers in Georgia.Streamflow and groundwater data are verified throughout the year by USGS hydrographers and made available to water-resource managers, recreationists, and Federal, State, and local agencies. Hydrologic conditions are determined by comparing the statistical analyses of data collected during the current water year to historical data. Changing hydrologic conditions underscore the need for accurate, timely data to allow informed decisions about the management and conservation of Georgia’s water resources for agricultural, recreational, ecological, and water-supply needs and in protecting life and property.

Orbital apocenter is not a sufficient condition for HST/STIS detection of Europa's water vapor aurora.

PubMed

Roth, Lorenz; Retherford, Kurt D; Saur, Joachim; Strobel, Darrell F; Feldman, Paul D; McGrath, Melissa A; Nimmo, Francis

2014-12-02

We report far-ultraviolet observations of Jupiter's moon Europa taken by Space Telescope Imaging Spectrograph (STIS) of the Hubble Space Telescope (HST) in January and February 2014 to test the hypothesis that the discovery of a water vapor aurora in December 2012 by local hydrogen (H) and oxygen (O) emissions with the STIS originated from plume activity possibly correlated with Europa's distance from Jupiter through tidal stress variations. The 2014 observations were scheduled with Europa near the apocenter similar to the orbital position of its previous detection. Tensile stresses on south polar fractures are expected to be highest in this orbital phase, potentially maximizing the probability for plume activity. No local H and O emissions were detected in the new STIS images. In the south polar region where the emission surpluses were observed in 2012, the brightnesses are sufficiently low in the 2014 images to be consistent with any H2O abundance from (0-5)×10(15) cm(-2). Large high-latitude plumes should have been detectable by the STIS, independent of the observing conditions and geometry. Because electron excitation of water vapor remains the only viable explanation for the 2012 detection, the new observations indicate that although the same orbital position of Europa for plume activity may be a necessary condition, it is not a sufficient condition. However, the December 2012 detection of coincident HI Lyman-α and OI 1304-Å emission surpluses in an ∼200-km high region well separated above Europa's limb is a firm result and not invalidated by our 2014 STIS observations.

Orbital apocenter is not a sufficient condition for HST/STIS detection of Europa's water vapor aurora

NASA Astrophysics Data System (ADS)

Roth, Lorenz; Retherford, Kurt D.; Saur, Joachim; Strobel, Darrell F.; Feldman, Paul D.; McGrath, Melissa A.; Nimmo, Francis

2014-12-01

We report far-ultraviolet observations of Jupiter's moon Europa taken by Space Telescope Imaging Spectrograph (STIS) of the Hubble Space Telescope (HST) in January and February 2014 to test the hypothesis that the discovery of a water vapor aurora in December 2012 by local hydrogen (H) and oxygen (O) emissions with the STIS originated from plume activity possibly correlated with Europa's distance from Jupiter through tidal stress variations. The 2014 observations were scheduled with Europa near the apocenter similar to the orbital position of its previous detection. Tensile stresses on south polar fractures are expected to be highest in this orbital phase, potentially maximizing the probability for plume activity. No local H and O emissions were detected in the new STIS images. In the south polar region where the emission surpluses were observed in 2012, the brightnesses are sufficiently low in the 2014 images to be consistent with any H2O abundance from (0-5)×1015 cm-2. Large high-latitude plumes should have been detectable by the STIS, independent of the observing conditions and geometry. Because electron excitation of water vapor remains the only viable explanation for the 2012 detection, the new observations indicate that although the same orbital position of Europa for plume activity may be a necessary condition, it is not a sufficient condition. However, the December 2012 detection of coincident HI Lyman-α and OI 1304-Å emission surpluses in an ∼200-km high region well separated above Europa's limb is a firm result and not invalidated by our 2014 STIS observations.

Biological, habitat, and water quality conditions in the upper Merced River drainage, Yosemite National Park, California, 1993-1996

USGS Publications Warehouse

Brown, Larry R.; Short, Terry M.

1999-01-01

The general conclusion from these studies is that water quality in the upper Merced River was very good from 1993-1996, despite high levels of human activities in some areas. Fish communities did not appear to be a useful indicator of habitat and water quality because of low species richness and the apparent importance of physical barriers in determining species distributions. Measurements of fish densities and size-distributions might be useful, but would be logistically difficult. Benthic algae and benthic invertebrates do appear to be useful in monitoring environmental conditions. Benthic algae may be more sensitive than benthic invertebrates to small environmental differences within years. Benthic algae were also more responsive than benthic invertebrates to differences in discharge between years. Thus, benthic invertebrates may be more useful in comparing environmental conditions between years, independent of discharge conditions.

Water resources activities in Kentucky, 1986

USGS Publications Warehouse

Faust, R. J.

1986-01-01

The U.S. Geological Survey, Water Resources Division, conducts three major types of activities in Kentucky in order to provide hydrologic information and understanding needed for the best management of Kentucky 's and the Nation 's water resources. These activities are: (1) Data collection and dissemination; (2) Water-resources appraisals (interpretive studies); and (3) Research. Activities described in some detail following: (1) collection of surface - and groundwater data; (2) operation of stations to collect data on water quality, atmospheric deposition, and sedimentation; (3) flood investigations; (4) water use; (5) small area flood hydrology; (6) feasibility of disposal of radioactive disposal in deep crystalline rocks; (7) development of a groundwater model for the Louisville area; (8) travel times for streams in the Kentucky River Basin; (9) the impact of sinkholes and streams on groundwater flow in a carbonate aquifer system; (10) sedimentation and erosion rates at the Maxey Flats Radioactive Waste Burial site; and (11) evaluation of techniques for evaluating the cumulative impacts of mining as applied to coal fields in Kentucky. (Lantz-PTT)

Overview of drought and hydrologic conditions in the United States and southern Canada, water years 1986-90

USGS Publications Warehouse

Holmes, Sandra L.

1992-01-01

This report describes the drought and hydrologic conditions in the United States and southern Canada during the 1986-90 water years. This drought, which spread from the Eastern United States, where it was referred to as 'the drought of the century,' through the Midwest to the West Coast, brought to mind the Dust Bowl era of the 1930's. However, generally localized floods were numerous, but only one hurricane (Hugo) was of any consequence to the United States, Puerto Rico, and the Virgin Islands during a coincident period of anomalously low hurricane activity. The drought began in early 1984 as an 'agricultural drought,' which is a precipitation deficiency that results in a lack of soil moisture that is detrimental to agricultural production. This condition did not affect streamflow until about March or April 1986. A 'hydrological drought,' which is far more serious and widespread than an agricultural drought, was apparent from the low streamflow conditions that occurred after April 1986. To illustrate the changing nature of the drought, maps and synopses of monthly hydrologic conditions for the water years 1986-90 are presented.

Geology and ground-water conditions in the Wilmington-Reading area, Massachusetts

USGS Publications Warehouse

Baker, John Augustus; Healy, H.G.; Hackett, O.M.

1964-01-01

The Wilmington-Reading area, as defined for this report, contains the headwaters of the Ipswich River in northeastern Massachusetts. Since World War II the growth of communities in this area and the change in character of some of them from rural to suburban have created new water problems and intensified old ones. The purpose of this report on ground-water conditions is to provide information that will aid in understanding and resolving some of these problems. The regional climate, which is humid and temperate, assures the area an ample natural supply of water. At the current stage of water-resources development a large surplus of water drains from the area by way of the Ipswich River during late autumn, winter, and spring each year and is unavailable for use during summer and early autumn, when during some years there is a general water deficiency. Ground water occurs both in bedrock and in the overlying deposits of glacial drift. The bedrock is a source of small but generally reliable supplies of water throughout the area. Glacial till also is a source of small supplies of water, but wells in till often fail to meet modern demands. Stratified glacial drift, including ice-contact deposits and outwash, yields small to large supplies of water. Stratified glacial drift forms the principal ground-water reservoir. It partly fills a system of preglacial valleys corresponding roughly to the valleys of the present Ipswich River system and is more than 100 feet thick at places. The ice-contact deposits generally are more permeable than the outwash deposits. Ground water occurs basically under water-table conditions. Recharge in the Wilmington-Reading area is derived principally from precipitation on outcrop areas of ice-contact deposits and outwash during late autumn, winter. and spring. It is estimated that the net annual recharge averages about 10 inches and generally ranges from 5 inches during unusually dry years to 15 inches during unusually wet years. Ground water

Voltammogram of stainless steel/Fe-Co-Ni electrode on water electrolysis in base condition with dahlia pinnata tuber starch media

NASA Astrophysics Data System (ADS)

Isana S. Y., L.; Yuanita, Dewi; Sulistyani, Al, Heru Pratomo

2017-08-01

Hydrogen production in a safe, enviromentally friendly, and inexpensive is an attempt to realize energy needs commercially, one of them is electrolysis. Many attempts which relate with water electrolysis had been conducted to produce hydrogen, for example by using wastewater as water substitution. The research is to study the effect of dahlia pinnata tuber starch to stainless steel/Fe-Co-Ni electrode activity on water electrolysis in base condition. Stainless steel/Fe-Co-Ni electrode activity for breaking the water molecules eventually is better than stainless steel electrode, either there is existance of dahlia pinnata tuber starch or not. The presence of dahlia pinnata tuber starch apparently makes the covering on surface of the electrode so the catalytic activity of the electrode is reduced. Covering is mostly affected by dahlia pinnata tuber starch concentration. Wastewater which contains starch, especially dahlia pinnata tuber starch, obviously is not good enough because hydrogen production rate becomes obstructed.

Water-quality conditions in Upper Klamath Lake, Oregon, 2002-04

USGS Publications Warehouse

Wood, Tamara M.; Hoilman, Gene R.; Lindenberg, Mary K.

2006-01-01

Eleven (2002) to 14 (2003 and 2004) continuous water-quality monitors that measured pH, dissolved oxygen, temperature, and specific conductance, were placed in Upper Klamath Lake to support a telemetry tracking study of endangered adult shortnose and Lost River suckers. Samples for the analysis of chlorophyll a and nutrients were collected at a subset of the water-quality monitor sites in each year. The seasonal pattern in the occurrence of supersaturated dissolved oxygen concentrations and high pH associated with photosynthetic activity, as well as the undersaturated dissolved oxygen concentrations associated with oxygen demand through respiration and decay in excess of photosynthetic production, were well described by the dynamics of the massive blooms of Aphanizomenon flos aquae (AFA) that occur each year. Data from the continuous monitors provided a means to quantify the occurrence, duration, and spatial extent of water-quality conditions potentially harmful to fish (dissolved- oxygen concentration less than 4 milligrams per liter, pH greater than 9.7, and temperature greater than 28 degrees Celsius) in the northern part of the lake, where the preferred adult sucker habitat is found. There were few observations of temperature greater than 28 degrees Celsius, suggesting that temperature is not a significant source of chronic stress to fish, although its role in the spread of disease is harder to define. Observations of pH greater than 9.7 were common during times when the AFA bloom was growing rapidly, so pH may be a source of chronic stress to fish. Dissolved oxygen concentrations less than 4 milligrams per liter were common in all 3 years at the deeper sites, in the lower part of the water column and for short periods during the day. Less common were instances of widespread low dissolved oxygen, throughout the water column and persisting through the entire day, but this was the character of a severe low dissolved oxygen event (LDOE) that culminated in the

US EPA/ORD Condition Assessment Research for Drinking Water Conveyance Infrastructure

EPA Science Inventory

This presentation describes research on condition assessment for drinking water transmission and distribution systems that EPA is conducting under the U.S. Environmental Protection Agency’s Aging Water Infrastructure (AWI) Research Program. This research program will help U.S. ...

Optimization of Water Management of Cranberry Fields under Current and Future Climate Conditions

NASA Astrophysics Data System (ADS)

Létourneau, G.; Gumiere, S.; Mailhot, E.; Rousseau, A. N.

2016-12-01

In North America, cranberry production is on the rise. Since 2005, land area dedicated to cranberry doubled, principally in Canada. Recent studies have shown that sub-irrigation could lead to improvements in yield, water use efficiency and pumping energy requirements compared to conventional sprinkler irrigation. However, the experimental determination of the optimal water table level of each production site may be expensiveand time-consuming. The primary objective of this study is to optimize the water table level as a function of typical soil properties, and climatic conditions observed in major production areas using a numerical modeling approach. The second objective is to evaluate the impacts of projected climatic conditions on water management of cranberry fields. To that end, cranberry-specific management operations such as harvest flooding, rapid drainage following heavy rainfall, or hydric stress management during dry weather conditions were simulated with the HYDRUS 2D software. Results have shown that maintaining the water table approximately at 60 cm provides optimal results for most of the studied soils. However, under certain extreme climatic conditions, the drainage system design may not allow maintaining optimal hydric conditions for cranberry growth. The long-term benefit of this study has potential to advance the design of drainage/sub-irrigation systems.

Water Pollution Scrubber Activity Simulates Pollution Control Devices.

ERIC Educational Resources Information Center

Kennedy, Edward C., III; Waggoner, Todd C.

2003-01-01

A laboratory activity caused students to think actively about water pollution. The students realized that it would be easier to keep water clean than to remove pollutants. They created a water scrubbing system allowing them to pour water in one end and have it emerge clean at the other end. (JOW)

Summary of hydrologic conditions in Kansas, water year 2016

USGS Publications Warehouse

Louen, Justin M.

2017-04-06

The U.S. Geological Survey (USGS), in cooperation with Federal, State, and local agencies, maintains a long-term network of hydrologic monitoring sites in Kansas. Real-time data are collected at 216 streamgage sites and are verified throughout the year with regular measurements of streamflow made by USGS personnel. Annual assessments of hydrologic conditions are made by comparing statistical analyses of current and historical water year (WY) data for the period of record. A WY is the 12-month period from October 1 through September 30 and is designated by the calendar year in which the period ends. Long-term monitoring of hydrologic conditions in Kansas provides critical information for water-supply management, flood forecasting, reservoir operations, irrigation scheduling, bridge and culvert design, ecological monitoring, and many other uses.

Stability and activity of lysozyme in stoichiometric and non-stoichiometric protic ionic liquid (PIL)-water systems

NASA Astrophysics Data System (ADS)

Wijaya, Emmy C.; Separovic, Frances; Drummond, Calum J.; Greaves, Tamar L.

2018-05-01

There has been a substantial increase in enzyme applications within the biochemical and pharmaceutical industries, for example, as industrial biocatalysts. However, enzymes have narrow marginal stability which makes them prone to become inactive and/or denature with a slight change in the solvent environment. Typically industrial applications require harsher solvent environments than enzyme native environments, and hence there is a need to understand solvent-protein interactions in order to develop strategies to maintain, or enhance, the enzymatic activity under industrially relevant solvent conditions. Previously we have shown that protic ionic liquids (PILs) with water can have a stabilising effect on lysozyme, with a large variation dependent on which PIL ions are present, and the water concentration [E. C. Wijaya et al., Phys. Chem. Chem. Phys. 18(37), 25926-25936 (2016)]. Here we extend on this work using non-stoichiometric aqueous PIL solvents to investigate, and isolate, the role of pH and ionicity on enzymes. We have used the PILs ethylammonium nitrate (EAN) and ethanolammonium formate (EOAF) since our previous work has identified these as good solvents for lysozyme. Solvent libraries were made from these two PILs with an additional precursor acid or base to modify the acidity/basicity of the neutral stoichiometric PIL, and with water added, to have solutions with 4-17 mol. % of the PIL ions in water. Molar ratios of base:acid were varied between 1:1.05 and 2:1 for EAN and 1:1.25 and 2:1 for EOAF, which enabled from highly basic to highly acidic solutions to be obtained. This was to modify the acidity/basicity of the neutral stoichiometric PILs, without the addition of buffers. The structure and stability of hen egg white lysozyme (HEWL) were explored under these solvent conditions using synchrotron small angle X-ray scattering (SAXS), Fourier transform infrared (FTIR), and activity assays. The radius of gyration and Kratky plots obtained from the SAXS data

Risk in the mist? Deriving data to quantify microbial health risks associated with aerosol generation by water-efficient devices during typical domestic water-using activities.

PubMed

O'Toole, J; Keywood, M; Sinclair, M; Leder, K

2009-01-01

The aim of this study was to address existing data gaps and to determine the size distribution of aerosols associated with water-efficient devices during typical domestic activities. This information is important to assist in understanding infection spread during water-using activities and in designing water regulations. Three water-using scenarios were evaluated: i) showering using a water-efficient showerhead; ii) use of a high pressure spray unit for cleaning cars and iii) toilet flushing using a dual flush low volume flush device. For each scenario a control condition (conventional lower efficiency device) was selected for benchmarking purposes. Shower module results highlighted the complexity of particle generation and removal processes and showed that more than 90% of total particle mass in the breathing zone was attributed to particle diameters greater than 6 mum. Conversely, results for car washing experiments showed that particle diameters up to 6 mum constituted the major part of the total mass generated by both water-efficient and conventional devices. Even under worse case scenario conditions for toilet flushing, particle measurements were at or below the level of detection of the measuring instrumentation. The data provide information that assists in health risk assessment and in determining future research directions, including methodological aspects.

Arbuscular mycorrhizal symbiosis increases relative apoplastic water flow in roots of the host plant under both well-watered and drought stress conditions

PubMed Central

Bárzana, Gloria; Aroca, Ricardo; Paz, José Antonio; Chaumont, François; Martinez-Ballesta, Mari Carmen; Carvajal, Micaela; Ruiz-Lozano, Juan Manuel

2012-01-01

Background and Aims The movement of water through mycorrhizal fungal tissues and between the fungus and roots is little understood. It has been demonstrated that arbuscular mycorrhizal (AM) symbiosis regulates root hydraulic properties, including root hydraulic conductivity. However, it is not clear whether this effect is due to a regulation of root aquaporins (cell-to-cell pathway) or to enhanced apoplastic water flow. Here we measured the relative contributions of the apoplastic versus the cell-to-cell pathway for water movement in roots of AM and non-AM plants. Methods We used a combination of two experiments using the apoplastic tracer dye light green SF yellowish and sodium azide as an inhibitor of aquaporin activity. Plant water and physiological status, root hydraulic conductivity and apoplastic water flow were measured. Key Results Roots of AM plants enhanced significantly relative apoplastic water flow as compared with non-AM plants and this increase was evident under both well-watered and drought stress conditions. The presence of the AM fungus in the roots of the host plants was able to modulate the switching between apoplastic and cell-to-cell water transport pathways. Conclusions The ability of AM plants to switch between water transport pathways could allow a higher flexibility in the response of these plants to water shortage according to the demand from the shoot. PMID:22294476

PETher - Physical Properties of Thermal Water under In-situ-Conditions

NASA Astrophysics Data System (ADS)

Herfurth, Sarah; Schröder, Elisabeth

2016-04-01

The objective of PETher, a research project funded by the German Federal Ministry for Economic Affairs and Energy (BMWi), is to experimentally determine thermo-physical properties (specific isobaric heat capacity, kinematic viscosity, density and thermal conductivity) of geothermal water in-situ-conditions (pressure, temperature, chemical composition including gas content of the brine) present in geothermal applications. Knowing these thermo-physical properties reduces the uncertainties with respect to estimating the thermal output and therefore the economic viability of the power plant. Up to now, only a limited number of measurements of selected physical properties have been made, usually under laboratory conditions and for individual geothermal plants. In-situ measured parameters, especially in the temperature range of 120°C and higher, at pressures of 20 bar and higher, as well as with a salinity of up to 250 g/l, are sparse to non-existing. Therefore, pure water properties are often used as reference data and for designing the power plant and its components. Currently available numerical models describing the thermo-physical properties are typically not valid for the conditions in geothermal applications and do not consider the substantial influence of the chemical composition of the thermal water. Also, actual geothermal waters have not been subject of detailed measurements systematically performed under operational conditions on a large-scale basis. Owing to the lack of reliable data, a validation of numerical models for investigating geothermal systems is not possible. In order to determine the dependency of the thermo-physical properties of geothermal water on temperature, pressure and salinity in-situ measurements are conducted. The measurements are taking place directly at several geothermal applications located in Germany's hydrogeothermal key regions. In order to do this, a mobile testing unit was developed and refined with instruments specifically

Analysis of the performance and space-conditioning impacts of dedicated heat-pump water heaters

NASA Astrophysics Data System (ADS)

Morrison, L.; Swisher, J.

1980-12-01

The operation of a newly marketed dedicated heat pump water heater (HPWH) which utilizes an air to water heat pump, costs about $1000 installed, and obtains a coefficient of performance (COP) of about 2.0 in laboratory and field tests, is a space conditioning benefit if an air conditioning load exists and a penalty if a space heating load exists. A simulation was developed to model the thermal performance of a residence with resistance baseboard heat, air conditioning, and either heat pump or resistance water heating. The building characteristics were adapted (Madison, Wisconsin; Washington, DC; and Ft. Worth, Texas) and the system was simulated for a year with typical weather data. For each city, HPWH COPs are calculated monthly and yearly. The water heating and space conditioning energy requirements of HPWH operation are compared with those of resistance water heater operation to determine the relative performance ratio of the HPWH.

AB INITIO Molecular Dynamics Simulations of Water Under Static and Shock Compressed Conditions

NASA Astrophysics Data System (ADS)

Goldman, Nir; Fried, Laurence E.; Mundy, Christopher J.; Kuo, I.-F. William; Curioni, Alessandro; Reed, Evan J.

2007-12-01

We report herein a series of ab initio simulations of water under both static and shocked conditions. We have calculated the coherent x-ray scattering intensity of several phases of water under high pressure, using ab initio Density Functional Theory (DFT). We provide new atomic scattering form factors for water at extreme conditions, which take into account frequently neglected changes in ionic charge and electron delocalization. We have also simulated liquid water undergoing shock loading of velocities from 5-11 km/s using the Multi-Scale Shock Technique (MSST). We show that Density Functional Theory (DFT) molecular dynamics results compare extremely well to experiments on the water shock Hugoniot.

Anodic activation of iron corrosion in clay media under water-saturated conditions at 90 degrees C: characterization of the corrosion interface.

PubMed

Schlegel, Michel L; Bataillon, Christian; Blanc, Cécile; Prêt, Dimitri; Foy, Eddy

2010-02-15

To understand the process governing iron corrosion in clay over centuries, the chemical and mineralogical properties of solids formed by free or anodically activated corrosion of iron in water-saturated clay at 90 degrees C over 4 months were probed using microscopic and spectroscopic techniques. Free corrosion led to the formation of an internal discontinuous thin (<3 microm thick) magnetite layer, an external layer of Fe-rich phyllosilicate, and a clay transformation layer containing Ca-doped siderite (Ca(0.2)Fe(0.8)CO(3)). The thickness of corroded iron equaled approximately 5-7 microm, consistent with previous studies. Anodic polarization resulted in unequally distributed corrosion, with some areas corrosion-free and others heavily corroded. Activated corrosion led to the formation of an inner magnetite layer, an intermediate Fe(2)CO(3)(OH)(2) (chukanovite) layer, an outer layer of Fe-rich 7 A-phyllosilicate, and a transformed matrix layer containing siderite (FeCO(3)). The corroded thickness was estimated to 85 microm, less than 30% of the value expected from the supplied anodic charge. The difference was accounted for by reoxidation at the anodically polarized surface of cathodically produced H(2)(g). Thus, free or anodically activated corroding conditions led to structurally similar interfaces, indicating that anodic polarization can be used to probe the long-term corrosion of iron in clay. Finally, corrosion products retained only half of Fe oxidized by anodic activation. Missing Fe probably migrated in the clay, where it could interact with radionuclides released by alteration of nuclear glass.

GROUND WATER QUALITY SURROUNDING LAKE TEXOMA DURING SHORT-TERM DROUGHT CONDITIONS

EPA Science Inventory

Water quality data from 55 monitoring wells during drought conditions surrounding Lake Texoma, located on the border of Oklahoma and Texas, was compared to assess the influence of drought on groundwater quality. During the drought month of October, water table levels were three ...

CORE MUSCLE ACTIVITY DURING THE CLEAN AND JERK LIFT WITH BARBELL VERSUS SANDBAGS AND WATER BAGS.

PubMed

Calatayud, Joaquin; Colado, Juan C; Martin, Fernando; Casaña, José; Jakobsen, Markus D; Andersen, Lars L

2015-11-01

While the traditional clean and jerk maneuver implies simultaneous participation of a large number of muscle groups, the use of this exercise with some variations to enhance core muscle activity remains uninvestigated. The purpose of this study was to compare the muscle activity during clean and jerk lift when performed with a barbell, sandbag and a water bag at same absolute load. Descriptive, repeated-measures study. Twenty-one young fit male university students (age: 25 ± 2.66 years; height: 180.71 ± 5.42 cm; body mass: 80.32 ± 9.8 kg; body fat percentage: 12.41 ± 3.56 %) participated. Surface electromyographic (EMG) signals were recorded from the anterior deltoid (AD), external oblique (OBLIQ), lumbar erector spinae (LUMB), and gluteus medius (GM) and were expressed as a percentage of the maximum voluntary isometric contraction (MVIC). There were no significantly significant differences for AD muscle activity between conditions, whereas muscle activation values for OBLIQ (60%MVIC), GM (29%MVIC) and LUMB (85%MVIC) were significantly higher during the water bag power clean and jerk maneuver when compared with the other conditions. The clean and jerk is an exercise that may be used to enhance core muscle activity. Performing the maneuver with water bags resulted in higher core muscle activity compared with sandbag and standard barbell versions. 3.

The evolution of hydrological and water quality conditions on Techirghiol Lake

NASA Astrophysics Data System (ADS)

Maftei, Carmen; Buta, Constantin; Tofan, Lucica

2015-04-01

Changes in climate and environment conditions alter the hydraulic and chemical properties of lakes. With a surface from 1300ha, the Techirghiol Lake, situated on the littoral of the Black Sea at 15km from Constanta town, is considered the greatest hypersaline lake of Romania very well known (from 1891) especially for the curative qualities of its water and mud. Physical and geographical conditions associated with an arid climate regime - where the annual precipitation is less than 400mm and the average temperatures exceed (lead evaporative potential to 700-1000mm), cause a strong concentration of mineral salts that give the lake an excessive salinity. In conditions of excessive salinity forms a therapeutic mud as a result of bacterial decomposition of aquatic organisms that have done there, especially crustaceans Arthemia and algae that live in water. This mud, highly hydrated, rich in minerals, has therapeutic properties, for this reason in Techirghiol has developed a strong health resort. Fresh water is a threat to the therapeutic lake properties. In hydrological year 1961-1962, the overland flow value to the lake was approximately 0.4 million m3, and from 1972-1973 the value reached 6 million cubic meters per year a great contribution was from the irrigation water. One of the consequences is the increasing of the lake level and the second is the decreasing of salinity. For this reason a hydraulic work system has been built to separate the saline water of the lake and the freshwater. The aim of this paper is to investigate the hydrologic and chemical responses of the Techirghiol Lake to the changes in climate and environment conditions.

Groundwater infiltration, surface water inflow and sewerage exfiltration considering hydrodynamic conditions in sewer systems.

PubMed

Karpf, Christian; Hoeft, Stefan; Scheffer, Claudia; Fuchs, Lothar; Krebs, Peter

2011-01-01

Sewer systems are closely interlinked with groundwater and surface water. Due to leaks and regular openings in the sewer system (e.g. combined sewer overflow structures with sometimes reverse pressure conditions), groundwater infiltration and surface water inflow as well as exfiltration of sewage take place and cannot be avoided. In the paper a new hydrodynamic sewer network modelling approach will be presented, which includes--besides precipitation--hydrographs of groundwater and surface water as essential boundary conditions. The concept of the modelling approach and the models to describe the infiltration, inflow and exfiltration fluxes are described. The model application to the sewerage system of the City of Dresden during a flood event with complex conditions shows that the processes of infiltration, exfiltration and surface water inflows can be described with a higher reliability and accuracy, showing that surface water inflow causes a pronounced system reaction. Further, according to the simulation results, a high sensitivity of exfiltration rates on the in-sewer water levels and a relatively low influence of the dynamic conditions on the infiltration rates were found.

Atomically monodisperse nickel nanoclusters as highly active electrocatalysts for water oxidation

NASA Astrophysics Data System (ADS)

Joya, Khurram S.; Sinatra, Lutfan; Abdulhalim, Lina G.; Joshi, Chakra P.; Hedhili, M. N.; Bakr, Osman M.; Hussain, Irshad

2016-05-01

Achieving water splitting at low overpotential with high oxygen evolution efficiency and stability is important for realizing solar to chemical energy conversion devices. Herein we report the synthesis, characterization and electrochemical evaluation of highly active nickel nanoclusters (Ni NCs) for water oxidation at low overpotential. These atomically precise and monodisperse Ni NCs are characterized by using UV-visible absorption spectroscopy, single crystal X-ray diffraction and mass spectrometry. The molecular formulae of these Ni NCs are found to be Ni4(PET)8 and Ni6(PET)12 and are highly active electrocatalysts for oxygen evolution without any pre-conditioning. Ni4(PET)8 are slightly better catalysts than Ni6(PET)12 which initiate oxygen evolution at an amazingly low overpotential of ~1.51 V (vs. RHE; η ~ 280 mV). The peak oxygen evolution current density (J) of ~150 mA cm-2 at 2.0 V (vs. RHE) with a Tafel slope of 38 mV dec-1 is observed using Ni4(PET)8. These results are comparable to the state-of-the-art RuO2 electrocatalyst, which is highly expensive and rare compared to Ni-based materials. Sustained oxygen generation for several hours with an applied current density of 20 mA cm-2 demonstrates the long-term stability and activity of these Ni NCs towards electrocatalytic water oxidation. This unique approach provides a facile method to prepare cost-effective, nanoscale and highly efficient electrocatalysts for water oxidation.Achieving water splitting at low overpotential with high oxygen evolution efficiency and stability is important for realizing solar to chemical energy conversion devices. Herein we report the synthesis, characterization and electrochemical evaluation of highly active nickel nanoclusters (Ni NCs) for water oxidation at low overpotential. These atomically precise and monodisperse Ni NCs are characterized by using UV-visible absorption spectroscopy, single crystal X-ray diffraction and mass spectrometry. The molecular formulae of these

[Combined use of active chlorine and coagulants for drinking water purification and disinfection].

PubMed

Rakhmanin, Iu A; Zholdakova, Z I; Poliakova, E E; Kir'ianova, L F; Miasnikov, I N; Tul'skaia, E A; Artemova, T Z; Ivanova, L V; Dmitrieva, R A; Doskina, T V

2004-01-01

The authors made an experimental study of the efficiency of water purification procedures based on the combined use of active chlorine and coagulants and hygienically evaluated the procedures. The study included the evaluation of water disinfection with various coagulants and active chlorine; the investigation of the processes of production of deleterious organic chlorine compounds; the assessment of the quality of water after its treatment. The coagulants representing aluminum polyoxychloride: RAX-10 (AQUA-AURATE 10) and RAX-18 (AQUA-AURATE 18), and aluminum sulfate, technically pure grade were tested. The treatment of river water with the coagulants RAX-10 and RAX-18, followed by precipitation, filtration, and chlorination under laboratory conditions, was shown to result in water disinfection to the levels complying with the requirements described in SanPiN 2.1.4.1074-01. RAX-18 showed the best disinfecting activity against total and heat-tolerant coliform bacteria, but also to the highly chlorine-resistant microrganisms--the spores of sulfite-reducing Clostridia, phages, and viruses. Since the coagulants have an increased sorptive capacity relative to humus and other organic substances, substitution of primary chlorination for coagulant treatment may induce a reduction in the risk of formation of oncogenically and mutagenically hazardous chlorinated hydrocarbons.

Fluorometric Measurement of Individual Stomata Activity and Transpiration via a “Brush-on”, Water-Responsive Polymer

PubMed Central

Seo, Minjeong; Park, Dong-Hoon; Lee, Chan Woo; Jaworski, Justyn; Kim, Jong-Man

2016-01-01

Much of atmospheric water originates from transpiration, the process by which plants release H2O from pores, known as stomata, that simultaneously intake CO2 for photosynthesis. Controlling stomatal aperture can regulate the extent of water transport in response to dynamic environmental factors including osmotic stress, temperature, light, and wind. While larger leaf regions are often examined, the extent of water vapor release from individual stomata remains unexplored. Using a “brush-on” sensing material, we can now assess transpiration using a water-responsive, polydiacetylene-based coating on the leaves surfaces. By eliciting a fluorometric signal to passing water vapor, we obtained information regarding the activity of individual stomata. In this demonstration, our results prove that this coating can identify the proportion of active stomata and the extent of transpirational diffusion of water in response to different conditions. PMID:27578430

Ground-water conditions at Beale Air Force Base and vicinity, California

USGS Publications Warehouse

Page, R.W.

1980-01-01

Ground-water conditions were studied in a 168-square-mile area between the Sierra Nevada and the Feather River in Yuba County, Calif. The area is in the eastern part of the Sacramento Valley and includes most of Beale Air Force Base. Source, occurrence, movement, and chemical quality of the ground water were evaluated. Ground water occurs in sedimentary and volcanic rocks of Tertiary and Quaternary age. The base of the freshwater is in the undifferentiated sedimentary rocks of Oligocene and Eocene age, that contain water of high dissolved-solids concentration. The ground water occurs under unconfined and partly confined conditions. At Beale Air Force Base it is at times partly confined. Recharge is principally from the rivers. Pumpage in the study area was estimated to be 129,000 acre-feet in 1975. In the 1960's, water levels in most parts of the study area declined less rapidly than in earlier years or became fairly stable. In the 1970's, water levels at Beale Air Force Base declined only slightly. Spacing of wells on the base and rates of pumping are such that excessive pumping interference is avoided. Water quality at the base and throughout the study area is generally good. Dissolved-solids concentrations are 700 to 900 milligrams per liter in the undifferentiated sedimentary rocks beneath the base well field. (USGS)

Human activities and its Responses to Glacier Melt Water Over Tarim River Basin

NASA Astrophysics Data System (ADS)

He, Hai; Zhou, Shenbei; Bai, Minghao

2017-04-01

Tarim River Basin lies in the south area of Xinjiang Uygur Autonomous Region, the north-west area of China. It is the longest inland river of China. Being far away from ocean and embraced by high mountains, Tarim River Basin is the typical arid region in the world. The intensity of human activities increased rapidly in Tarim River Basin since 1980's and water resources lacking is the major issue restricting the development of social economy. The glacier melt water plays an important role for the regional social and economic development, and it accounts for 40% of mountain-pass runoff. It is a fragile mutual-dependent relationship between local sustainable development and runoff. Under the background of global change glacier melt water process has also changed especially in the arid and semi-arid region. Due to climate change, glacier in Tarim River Basin has melted in an observed way since 1980s, together with increasing trend of annual rainfall and virgin flow in mountain basins. Correspondingly, human activity gets more frequent since 1970s, resulting into the obvious fragile mutual-dependent relationship between basin runoff and water use amount. Through an analysis of meteorological, hydrological and geographical observation data from 1985 to 2015, this thesis make a multi-factor variance analysis of population, cultivation area, industrial development and runoff in upstream and mid-stream of Tarim River under changing conditions. Furthermore, the regulation function of natural factors and water demand management factors on relationship between runoff and water using amount are discussed, including temperature, rainfall, and evaporation, water conservation technology and soil-water exploitation administrative institutions. It concludes that: first, increase in glacier runoff, rainfall amount, and virgin flow haven't notably relieved ecological issue in Tarim River Basin, and even has promoted water use behaviour in different flowing areas and noticeably reduced

Prokaryotic degradation of high molecular weight dissolved organic matter in the deep-sea waters of NW Mediterranean Sea under in situ temperature and pressure conditions during contrasted hydrological conditions

NASA Astrophysics Data System (ADS)

Tamburini, C.; Boutrif, M.; Garel, M.; Sempéré, R.; Repeta, D.; Charriere, B.; Nerini, D.; Panagiotopoulos, C.

2016-02-01

The contribution of the semi-labile dissolved organic carbon (DOC) to the global prokaryotic production has been assessed in very few previous studies. Some experiments show rapid utilization of semi-reactive DOC by prokaryotes, while other experiments show almost no utilization at all. However, all these studies did not take into account the role of hydrostatic pressure for the degradation of organic matter. In this study, we investigate (1) the degradation of "natural" high molecular weight DOM HMW-DOM (obtained after ultrafiltration) and (2) the uptake of labeled extracellular polymeric substances (3H-EPS) incubated with deep-sea water samples (2000 m-depth, NW Mediterranean Sea) under in situ pressure conditions (HP) and under atmospheric compression after decompression of the deep samples (ATM) during stratified and mixed water conditions (deep sea convection). Our results indicated that during HP incubations DOC exhibited the highest degradation rates (kHP DOC = 0.82 d-1) compared to the ATM conditions were no or few degradation was observed (kATM DOC= 0.007 d-1). An opposite trend was observed for the HP incubations from mixed deep water masses. HP incubation measurements displayed the lowest DOC degradation (kHP DOC=0.031 d-1) compared to the ATM conditions (kATM DOC=0.62 d-1). These results imply the presence of allochthonous prokaryotic cells in deep-sea samples after a winter water mass convection. Same trends were found using 3H-EPS uptake rates which were higher at HP than at ATM conditions during stratified period conditions whereas the opposite patterns were observed during deep-sea convection event. Moreover, we found than Euryarchaea were the main contributors to 3H-EPS assimilation at 2000m-depth, representing 58% of the total cells actively assimilating 3H-EPS. This study demonstrates that remineralization rates of semi-labile DOC in deep NW Med. Sea are controlled by the prokaryotic communities, which are influenced by the hydrological

Ground-water conditions in the central Virgin River basin, Utah

USGS Publications Warehouse

Cordova, R.M.; Sandberg, G.W.; McConkie, Wilson

1972-01-01

Water-rights problems have occurred in the central Virgin River basin and are expected to increase as development of the water resources increases. The Utah State Engineer needs a basic knowledge of ground-water conditions and of the relation of ground water to surface water as a first step to understanding and resolving the problems. Accordingly, the State Engineer requested the U. S. Geological Survey to make a ground-water investigation of the central Virgin River basin as part of the Statewide cooperative agreement with the Utah Department of Natural Resources. The investigation was begun July 1, 1968, and fieldwork was completed in August 1970. Detailed information was obtained for the principal aquifers and for recharge, movement, discharge, storage, utilization, and chemical quality of ground water. A progress report (Cordova, Sandberg, and McConkie, 1970) describes the general findings in the first year of the investigation.

Water-resources activities in Florida, 1988-89

USGS Publications Warehouse

Glenn, Mildred E.

1989-01-01

This report contains summary statements of water resources activities in Florida conducted by the Water Resources Division of the U.S. Geological Survey in cooperation with Federal, State , and local agencies during 1988. These activities are part of the Federal program of appraising the Nation 's water resources. Included are brief descriptions of the nature and scope of all active studies, summaries of significant results for 1988 and anticipated accomplishments during 1989. Water resources appraisals in Florida are highly diversified, ranging from hydrologic records networks to interpretive appraisals of water resources and applied research to develop investigative techniques. Thus, water-resources investigations range from basic descriptive water-availability studies for areas of low-intensity water development and management to sophisticated cause and effect studies in areas of high-intensity water development and management. The interpretive reports and records that are products of the investigations are a principal hydrologic foundation upon which the plans for development, management, and protection of Florida 's water resources may be used. Water data and information required to implement sound water-management programs in highly urbanized areas relate to the quantity and quality of storm runoff, sources of aquifer contamination, injection of wastes into deep strata, underground storage of freshwater, artificial recharge of aquifers, environmental effects of reuse of water, and effects of land development on changes in ground-and surface-water quality. In some parts of the State broad areas are largely rural. Future growth is anticipated in many of these. This report is intended to inform those agencies vitally interested in the water resources of Florida as to the current status and objectives of the U.S. Geological Survey cooperative program. The mission of this program is to collect, interpret, and publish information on water resources. Almost all of

Testing the applicability of rapid on-site enzymatic activity detection for surface water monitoring

NASA Astrophysics Data System (ADS)

Stadler, Philipp; Vogl, Wolfgang; Juri, Koschelnik; Markus, Epp; Maximilian, Lackner; Markus, Oismüller; Monika, Kumpan; Peter, Strauss; Regina, Sommer; Gabriela, Ryzinska-Paier; Farnleitner Andreas, H.; Matthias, Zessner

2015-04-01

On-site detection of enzymatic activities has been suggested as a rapid surrogate for microbiological pollution monitoring of water resources (e.g. using glucuronidases, galactosidases, esterases). Due to the possible short measuring intervals enzymatic methods have high potential as near-real time water quality monitoring tools. This presentation describes results from a long termed field test. For twelve months, two ColiMinder devices (Vienna Water Monitoring, Austria) for on-site determination of enzymatic activity were tested for stream water monitoring at the experimental catchment HOAL (Hydrological Open Air Laboratory, Center for Water Resource Systems, Vienna University of Technology). The devices were overall able to follow and reflect the diverse hydrological and microbiological conditions of the monitored stream during the test period. Continuous data in high temporal resolution captured the course of enzymatic activity in stream water during diverse rainfall events. The method also proofed sensitive enough to determine diurnal fluctuations of enzymatic activity in stream water during dry periods. The method was able to capture a seasonal trend of enzymatic activity in stream water that matches the results gained from Colilert18 analysis for E. coli and coliform bacteria of monthly grab samples. Furthermore the comparison of ColiMinder data with measurements gained at the same test site with devices using the same method but having different construction design (BACTcontrol, microLAN) showed consistent measuring results. Comparative analysis showed significant differences between measured enzymatic activity (modified fishman units and pmol/min/100ml) and cultivation based analyses (most probable number, colony forming unit). Methods of enzymatic activity measures are capable to detect ideally the enzymatic activity caused by all active target bacteria members, including VBNC (viable but nonculturable) while cultivation based methods cannot detect VBNC

Symbiotic activity of pea (Pisum sativum) after application of Nod factors under field conditions.

PubMed

Siczek, Anna; Lipiec, Jerzy; Wielbo, Jerzy; Kidaj, Dominika; Szarlip, Paweł

2014-04-29

Growth and symbiotic activity of legumes are mediated by Nod factors (LCO, lipo-chitooligosaccharides). To assess the effects of application of Nod factors on symbiotic activity and yield of pea, a two-year field experiment was conducted on a Haplic Luvisol developed from loess. Nod factors were isolated from Rhizobium leguminosarum bv. viciae strain GR09. Pea seeds were treated with the Nod factors (10⁻¹¹ M) or water (control) before planting. Symbiotic activity was evaluated by measurements of nitrogenase activity (acetylene reduction assay), nodule number and mass, and top growth by shoot mass, leaf area, and seed and protein yield. Nod factors generally improved pea yield and nitrogenase activity in the relatively dry growing season 2012, but not in the wet growing season in 2013 due to different weather conditions.

Active isotropic slabs: conditions for amplified reflection

NASA Astrophysics Data System (ADS)

Perez, Liliana I.; Matteo, Claudia L.; Etcheverry, Javier; Duplaá, María Celeste

2012-12-01

We analyse in detail the necessary conditions to obtain amplified reflection (AR) in isotropic interfaces when a plane wave propagates from a transparent medium towards an active one. First, we demonstrate analytically that AR is not possible if a single interface is involved. Then, we study the conditions for AR in a very simple configuration: normal incidence on an active slab immersed in transparent media. Finally, we develop an analysis in the complex plane in order to establish a geometrical method that not only describes the behaviour of active slabs but also helps to simplify the calculus.

Shallow ground-water conditions, Tom Green County, Texas

USGS Publications Warehouse

Lee, J.N.

1986-01-01

Pollution from oil-field activities may affect the quality of water in some isolated wells and in some areas in the county. No historical records are available for determining any changes in pesticides, minor elements, or bacteria.

Screening of lettuce germplasm for agronomic traits under low water conditions

USDA-ARS?s Scientific Manuscript database

After a preliminary screening of over 3,500 varieties, we selected 200 cultivars of butterhead, cos, crisphead, leaf, and stem lettuce (Lactuca sativa L.) and wild prickly lettuce (Lactuca serriola L.) to test under high water (150% ET) and low water (50% ET) conditions in the field, and tracked com...

Extension of the TRANSURANUS burnup model to heavy water reactor conditions

NASA Astrophysics Data System (ADS)

Lassmann, K.; Walker, C. T.; van de Laar, J.

1998-06-01

The extension of the light water reactor burnup equations of the TRANSURANUS code to heavy water reactor conditions is described. Existing models for the fission of 235U and the buildup of plutonium in a heavy water reactor are evaluated. In order to overcome the limitations of the frequently used RADAR model at high burnup, a new model is presented. After verification against data for the radial distributions of Xe, Cs, Nd and Pu from electron probe microanalysis, the model is used to analyse the formation of the high burnup structure in a heavy water reactor. The new model allows the analysis of light water reactor fuel rod designs at high burnup in the OECD Halden Heavy Water Reactor.

Using δ2H and δ18O in assessing water quality condition of the nation’s water

EPA Science Inventory

The Clean Water Act mandates reporting on the condition of the nation’s waters. The Environmental Protection Agency implemented National Aquatic Resource Surveys (NARS) to address this mandate, including the National Lakes Assessment conducted in 2007. This study focuses on whe...

Analysis of endocrine activity in drinking water, surface water and treated wastewater from six countries.

PubMed

Leusch, Frederic D L; Neale, Peta A; Arnal, Charlotte; Aneck-Hahn, Natalie H; Balaguer, Patrick; Bruchet, Auguste; Escher, Beate I; Esperanza, Mar; Grimaldi, Marina; Leroy, Gaela; Scheurer, Marco; Schlichting, Rita; Schriks, Merijn; Hebert, Armelle

2018-08-01

The aquatic environment can contain numerous micropollutants and there are concerns about endocrine activity in environmental waters and the potential impacts on human and ecosystem health. In this study a complementary chemical analysis and in vitro bioassay approach was applied to evaluate endocrine activity in treated wastewater, surface water and drinking water samples from six countries (Germany, Australia, France, South Africa, the Netherlands and Spain). The bioassay test battery included assays indicative of seven endocrine pathways, while 58 different chemicals, including pesticides, pharmaceuticals and industrial compounds, were analysed by targeted chemical analysis. Endocrine activity was below the limit of quantification for most water samples, with only two of six treated wastewater samples and two of six surface water samples exhibiting estrogenic, glucocorticoid, progestagenic and/or anti-mineralocorticoid activity above the limit of quantification. Based on available effect-based trigger values (EBT) for estrogenic and glucocorticoid activity, some of the wastewater and surface water samples were found to exceed the EBT, suggesting these environmental waters may pose a potential risk to ecosystem health. In contrast, the lack of bioassay activity and low detected chemical concentrations in the drinking water samples do not suggest a risk to human endocrine health, with all samples below the relevant EBTs. Copyright © 2018 Elsevier Ltd. All rights reserved.

Water soluble polysaccharides from Spirulina platensis: extraction and in vitro anti-cancer activity.

PubMed

Kurd, Forouzan; Samavati, Vahid

2015-03-01

Polysaccharides from Spirulina platensis algae (SP) were extracted by ultrasound-assisted extraction procedure. The optimal conditions for ultrasonic extraction of SP were determined by response surface methodology. The four parameters were, extraction time (X1), extraction temperature (X2), ultrasonic power (X3) and the ratio of water to raw material (X4), respectively. The experimental data obtained were fitted to a second-order polynomial equation. The optimum conditions were extraction time of 25 min, extraction temperature 85°C, ultrasonic power 90 W and ratio of water to raw material 20 mL/g. Under these optimal conditions, the experimental yield was 13.583±0.51%, well matched with the predicted models with the coefficients of determination (R2) of 0.9971. Then, we demonstrated that SP polysaccharides had strong scavenging activities in vitro on DPPH and hydroxyl radicals. Overall, SP may have potential applications in the medical and food industries. Copyright © 2015 Elsevier B.V. All rights reserved.

Signal Processing for Determining Water Height in Steam Pipes with Dynamic Surface Conditions

NASA Technical Reports Server (NTRS)

Lih, Shyh-Shiuh; Lee, Hyeong Jae; Bar-Cohen, Yoseph

2015-01-01

An enhanced signal processing method based on the filtered Hilbert envelope of the auto-correlation function of the wave signal has been developed to monitor the height of condensed water through the steel wall of steam pipes with dynamic surface conditions. The developed signal processing algorithm can also be used to estimate the thickness of the pipe to determine the cut-off frequency for the low pass filter frequency of the Hilbert Envelope. Testing and analysis results by using the developed technique for dynamic surface conditions are presented. A multiple array of transducers setup and methodology are proposed for both the pulse-echo and pitch-catch signals to monitor the fluctuation of the water height due to disturbance, water flow, and other anomaly conditions.

Foraging Activity Pattern Is Shaped by Water Loss Rates in a Diurnal Desert Rodent.

PubMed

Levy, Ofir; Dayan, Tamar; Porter, Warren P; Kronfeld-Schor, Noga

2016-08-01

Although animals fine-tune their activity to avoid excess heat, we still lack a mechanistic understanding of such behaviors. As the global climate changes, such understanding is particularly important for projecting shifts in the activity patterns of populations and communities. We studied how foraging decisions vary with biotic and abiotic pressures. By tracking the foraging behavior of diurnal desert spiny mice in their natural habitat and estimating the energy and water costs and benefits of foraging, we asked how risk management and thermoregulatory requirements affect foraging decisions. We found that water requirements had the strongest effect on the observed foraging decisions. In their arid environment, mice often lose water while foraging for seeds and cease foraging even at high energetic returns when water loss is high. Mice also foraged more often when energy expenditure was high and for longer times under high seed densities and low predation risks. Gaining insight into both energy and water balance will be crucial to understanding the forces exerted by changing climatic conditions on animal energetics, behavior, and ecology.

Archaeal Inorganic Pyrophosphatase Displays Robust Activity under High-Salt Conditions and in Organic Solvents.

PubMed

McMillan, Lana J; Hepowit, Nathaniel L; Maupin-Furlow, Julie A

2016-01-15

Soluble inorganic pyrophosphatases (PPAs) that hydrolyze inorganic pyrophosphate (PPi) to orthophosphate (Pi) are commonly used to accelerate and detect biosynthetic reactions that generate PPi as a by-product. Current PPAs are inactivated by high salt concentrations and organic solvents, which limits the extent of their use. Here we report a class A type PPA of the haloarchaeon Haloferax volcanii (HvPPA) that is thermostable and displays robust PPi-hydrolyzing activity under conditions of 25% (vol/vol) organic solvent and salt concentrations from 25 mM to 3 M. HvPPA was purified to homogeneity as a homohexamer by a rapid two-step method and was found to display non-Michaelis-Menten kinetics with a Vmax of 465 U · mg(-1) for PPi hydrolysis (optimal at 42°C and pH 8.5) and Hill coefficients that indicated cooperative binding to PPi and Mg(2+). Similarly to other class A type PPAs, HvPPA was inhibited by sodium fluoride; however, hierarchical clustering and three-dimensional (3D) homology modeling revealed HvPPA to be distinct in structure from characterized PPAs. In particular, HvPPA was highly negative in surface charge, which explained its extreme resistance to organic solvents. To demonstrate that HvPPA could drive thermodynamically unfavorable reactions to completion under conditions of reduced water activity, a novel coupled assay was developed; HvPPA hydrolyzed the PPi by-product generated in 2 M NaCl by UbaA (a "salt-loving" noncanonical E1 enzyme that adenylates ubiquitin-like proteins in the presence of ATP). Overall, we demonstrate HvPPA to be useful for hydrolyzing PPi under conditions of reduced water activity that are a hurdle to current PPA-based technologies. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Archaeal Inorganic Pyrophosphatase Displays Robust Activity under High-Salt Conditions and in Organic Solvents

PubMed Central

McMillan, Lana J.; Hepowit, Nathaniel L.

2015-01-01

Soluble inorganic pyrophosphatases (PPAs) that hydrolyze inorganic pyrophosphate (PPi) to orthophosphate (Pi) are commonly used to accelerate and detect biosynthetic reactions that generate PPi as a by-product. Current PPAs are inactivated by high salt concentrations and organic solvents, which limits the extent of their use. Here we report a class A type PPA of the haloarchaeon Haloferax volcanii (HvPPA) that is thermostable and displays robust PPi-hydrolyzing activity under conditions of 25% (vol/vol) organic solvent and salt concentrations from 25 mM to 3 M. HvPPA was purified to homogeneity as a homohexamer by a rapid two-step method and was found to display non-Michaelis-Menten kinetics with a Vmax of 465 U · mg−1 for PPi hydrolysis (optimal at 42°C and pH 8.5) and Hill coefficients that indicated cooperative binding to PPi and Mg2+. Similarly to other class A type PPAs, HvPPA was inhibited by sodium fluoride; however, hierarchical clustering and three-dimensional (3D) homology modeling revealed HvPPA to be distinct in structure from characterized PPAs. In particular, HvPPA was highly negative in surface charge, which explained its extreme resistance to organic solvents. To demonstrate that HvPPA could drive thermodynamically unfavorable reactions to completion under conditions of reduced water activity, a novel coupled assay was developed; HvPPA hydrolyzed the PPi by-product generated in 2 M NaCl by UbaA (a “salt-loving” noncanonical E1 enzyme that adenylates ubiquitin-like proteins in the presence of ATP). Overall, we demonstrate HvPPA to be useful for hydrolyzing PPi under conditions of reduced water activity that are a hurdle to current PPA-based technologies. PMID:26546423

Quality-Assurance Plan for Water-Quality Activities of the U.S. Geological Survey Montana Water Science Center

USGS Publications Warehouse

Lambing, John H.

2006-01-01

In accordance with guidelines set forth by the Office of Water Quality in the Water Resources Discipline of the U.S. Geological Survey (USGS), a quality-assurance plan has been created for use by the USGS Montana Water Science Center in conducting water-quality activities. This quality-assurance plan documents the standards, policies, and procedures used by the USGS Montana Water Science Center for activities related to the collection, processing, storage, analysis, and publication of water-quality data. The policies and procedures presented in this quality-assurance plan for water-quality activities complement the quality-assurance plans for surface-water and ground-water activities and suspended-sediment analysis.

Orion Ground Test Article Water Impact Tests: Photogrammetric Evaluation of Impact Conditions

NASA Technical Reports Server (NTRS)

Vassilakos, Gregory J.; Mark, Stephen D.

2018-01-01

The Ground Test Article (GTA) is an early production version of the Orion Crew Module (CM). The structural design of the Orion CM is being developed based on LS-DYNA water landing simulations. As part of the process of confirming the accuracy of LS-DYNA water landing simulations, the GTA water impact test series was conducted at NASA Langley Research Center (LaRC) to gather data for comparison with simulations. The simulation of the GTA water impact tests requires the accurate determination of the impact conditions. To accomplish this, the GTA was outfitted with an array of photogrammetry targets. The photogrammetry system utilizes images from two cameras with a specialized tracking software to determine time histories for the 3-D coordinates of each target. The impact conditions can then be determined from the target location data.

Versatile Oxide Films Protect FeCrAl Alloys Under Normal Operation and Accident Conditions in Light Water Power Reactors

NASA Astrophysics Data System (ADS)

Rebak, Raul B.

2018-02-01

The US has currently a fleet of 99 nuclear power light water reactors which generate approximately 20% of the electricity consumed in the country. Near 90% of the reactors are at least 30 years old. There are incentives to make the existing reactors safer by using accident tolerant fuels (ATF). Compared to the standard UO2-zirconium-based system, ATF need to tolerate loss of active cooling in the core for a considerably longer time while maintaining or improving the fuel performance during normal operation conditions. Ferritic iron-chromium-aluminum (FeCrAl) alloys have been identified as an alternative to replace current zirconium alloys. They contain Fe (base) + 10-22 Cr + 4-6 Al and may contain smaller amounts of other elements such as molybdenum and traces of others. FeCrAl alloys offer outstanding resistance to attack by superheated steam by developing an alumina oxide on the surface in case of a loss of coolant accident like at Fukushima. FeCrAl alloys also perform well under normal operation conditions both in boiling water reactors and pressurized water reactors because they are protected by a thin oxide rich in chromium. Under normal operation condition, the key element is Cr and under accident conditions it is Al.

[Effects of water conditions and controlled release urea on yield and leaf senescence physiological characteristics in summer maize.

PubMed

Li, Guang Hao; Liu, Ping Ping; Zhao, Bin; Dong, Shu Ting; Liu, Peng; Zhang, Ji Wang; Tian, Cui Xia; He, Zai Ju

2017-02-01

In an soil column experiment with Zhengdan 958 (a summer maize cultivar planted widely in China), treatments of three water levels,severe water stress W 1 which the soil moisture kept (35±5)% of the field capacity, mild water stress W 2 which was (55±5)%,normal water W 3 which was (75±5)%, and four levels of controlled release urea fertilizer (N 0 , N 1 was 150 kg N·hm -2 ,N 2 was 225 kg N·hm -2 and N 3 was 300 kg N·hm -2 ) were included to study the interactive effects of water and controlled release urea on yield and leaf senescence characteristics of summer maize. The results showed that the coupling of water and controlled release urea had significant effects on increasing yield, delaying the senescence and keeping the high efficiency of the functional leaves. Under the same nitrogen condition, yield, LAI, chlorophyll content and the activities of SOD, POD, CAT and soluble protein content in summer maize ear leaf were significantly increased with more water supplying, and the content of MDA decreased significantly. Under the condition of the same moisture, these indicators were also significantly increased with the increasing nitrogen application and MDA content was reduced significantly. However, these indicators (except MDA) of W 3 N 3 , W 3 N 2 and W 2 N 3 treatments were maintained at a higher level and the MDA content was lo-wer compared with other treatments despite the fact that there were no significant difference among these three treatments, which indicated that the interactive effects of water and controlled release urea had an important role in maintaining the function of ear leaf, delaying the leaf senescence, and was beneficial to the photosynthates production and obtaining higher yield of summer maize. Integrating the yield, LAI, chlorophyll content, various protective enzymes activity, MDA and soluble protein content, controlled release urea application rate of 225 kg N·hm -2 was the best treatment as the soil moisture content was (75±5

An Active Site Water Network in the Plasminogen Activator Pla from Yersinia pestis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eren, Elif; Murphy, Megan; Goguen, Jon

2010-08-13

The plasminogen activator Pla from Yersinia pestis is an outer membrane protease (omptin) that is important for the virulence of plague. Here, we present the high-resolution crystal structure of wild-type, enzymatically active Pla at 1.9 {angstrom}. The structure shows a water molecule located between active site residues D84 and H208, which likely corresponds to the nucleophilic water. A number of other water molecules are present in the active site, linking residues important for enzymatic activity. The R211 sidechain in loop L4 is close to the nucleophilic water and possibly involved in the stabilization of the oxyanion intermediate. Subtle conformational changesmore » of H208 result from the binding of lipopolysaccharide to the outside of the barrel, explaining the unusual dependence of omptins on lipopolysaccharide for activity. The Pla structure suggests a model for the interaction with plasminogen substrate and provides a more detailed understanding of the catalytic mechanism of omptin proteases.« less

Microbial growth associated with granular activated carbon in a pilot water treatment facility.

PubMed Central

Wilcox, D P; Chang, E; Dickson, K L; Johansson, K R

1983-01-01

The microbial dynamics associated with granular activated carbon (GAC) in a pilot water treatment plant were investigated over a period of 16 months. Microbial populations were monitored in the influent and effluent waters and on the GAC particles by means of total plate counts and ATP assays. Microbial populations between the influent and effluent waters of the GAC columns generally increased, indicating microbial growth. The dominant genera of microorganisms isolated from interstitial waters and GAC particles were Achromobacter, Acinetobacter, Aeromonas, Alcaligenes, Bacillus, Chromobacterium, Corynebacterium, Micrococcus, Microcyclus, Paracoccus, and Pseudomonas. Coliform bacteria were found in small numbers in the effluents from some of the GAC columns in the later months of the study. Oxidation of influent waters with ozone and maintenance of aerobic conditions on the GAC columns failed to appreciably enhance the microbial growth on GAC. PMID:6625567

Water uptake of clay and desert dust aerosol particles at sub- and supersaturated water vapor conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herich, Hanna; Tritscher, Torsten; Wiacek, Aldona

2009-11-01

Airborne mineral dust particles serve as cloud condensation nuclei (CCN), thereby influencing the formation and properties of warm clouds. It is therefore of particular interest how dust aerosols with different mineralogy behave when exposed to high relative humidity (RH) or supersaturation with respect to liquid water similar to atmospheric conditions. In this study the sub-saturated hygroscopic growth and the supersaturated cloud condensation nucleus activity of pure clays and real desert dust aerosols was determined using a hygroscopicity tandem differential mobility analyzer (HTDMA) and a cloud condensation nuclei counter (CCNC), respectively. Five different illite, montmorillonite and kaolinite clay samples as wellmore » as three desert dust samples (Saharan dust (SD), Chinese dust (CD) and Arizona test dust (ATD)) were used. Aerosols were generated both with a wet and a dry disperser and the water uptake was parameterized via the hygroscopicity parameter, κ. The hygroscopicity of dry generated dust aerosols was found to be negligible when compared to processed atmospheric aerosols, with CCNC derived κ values between 0.00 and 0.02. The latter value can be idealized as a particle consisting of 96.7% (by volume) insoluble material and ~3.3% ammonium sulfate. Pure clay aerosols were found to be generally less hygroscopic than real desert dust particles. All illite and montmorillonite samples had κ~0.003, kaolinites were least hygroscopic and had κ=0.001. SD (κ=0.023) was found to be the most hygroscopic dry-generated desert dust followed by CD (κ=0.007) and ATD (κ=0.003). Wet-generated dust showed an increased water uptake when compared to dry-generated samples. This is considered to be an artifact introduced by redistribution of soluble material between the particles while immersed in an aqueous medium during atomization, thus indicating that specification of the generation method is critically important when presenting such data. Any atmospheric

On Complex Water Conflicts: Role of Enabling Conditions for Pragmatic Resolution

NASA Astrophysics Data System (ADS)

Islam, S.; Choudhury, E.

2016-12-01

Many of our current and emerging water problems are interconnected and cross boundaries, domains, scales, and sectors. These boundary crossing water problems are neither static nor linear; but often are interconnected nonlinearly with other problems and feedback. The solution space for these complex problems - involving interdependent variables, processes, actors, and institutions - can't be pre-stated. We need to recognize the disconnect among values, interests, and tools as well as problems, policies, and politics. Scientific and technological solutions are desired for efficiency and reliability, but need to be politically feasible and actionable. Governing and managing complex water problems require difficult tradeoffs in exploring and sharing benefits and burdens through carefully crafted negotiation processes. The crafting of such negotiation process, we argue, constitutes a pragmatic approach to negotiation - one that is based on the identification of enabling conditions - as opposed to mechanistic casual explanations, and rooted in contextual conditions to specify and ensure the principles of equity and sustainability. We will use two case studies to demonstrate the efficacy of the proposed principled pragmatic approcah to address complex water problems.

A Web-Based Decision Support System for Assessing Regional Water-Quality Conditions and Management Actions

USGS Publications Warehouse

Booth, N.L.; Everman, E.J.; Kuo, I.-L.; Sprague, L.; Murphy, L.

2011-01-01

The U.S. Geological Survey National Water Quality Assessment Program has completed a number of water-quality prediction models for nitrogen and phosphorus for the conterminous United States as well as for regional areas of the nation. In addition to estimating water-quality conditions at unmonitored streams, the calibrated SPAtially Referenced Regressions On Watershed attributes (SPARROW) models can be used to produce estimates of yield, flow-weighted concentration, or load of constituents in water under various land-use condition, change, or resource management scenarios. A web-based decision support infrastructure has been developed to provide access to SPARROW simulation results on stream water-quality conditions and to offer sophisticated scenario testing capabilities for research and water-quality planning via a graphical user interface with familiar controls. The SPARROW decision support system (DSS) is delivered through a web browser over an Internet connection, making it widely accessible to the public in a format that allows users to easily display water-quality conditions and to describe, test, and share modeled scenarios of future conditions. SPARROW models currently supported by the DSS are based on the modified digital versions of the 1:500,000-scale River Reach File (RF1) and 1:100,000-scale National Hydrography Dataset (medium-resolution, NHDPlus) stream networks. ?? 2011 American Water Resources Association. This article is a U.S. Government work and is in the public domain in the USA.

Polymer optical fiber grating as water activity sensor

NASA Astrophysics Data System (ADS)

Zhang, Wei; Webb, David J.

2014-05-01

Controlling the water content within a product has long been required in the chemical processing, agriculture, food storage, paper manufacturing, semiconductor, pharmaceutical and fuel industries. The limitations of water content measurement as an indicator of safety and quality are attributed to differences in the strength with which water associates with other components in the product. Water activity indicates how tightly water is "bound," structurally or chemically, in products. Water absorption introduces changes in the volume and refractive index of poly(methyl methacrylate) PMMA. Therefore for a grating made in PMMA based optical fiber, its wavelength is an indicator of water absorption and PMMA thus can be used as a water activity sensor. In this work we have investigated the performance of a PMMA based optical fiber grating as a water activity sensor in sugar solution, saline solution and Jet A-1 aviation fuel. Samples of sugar solution with sugar concentration from 0 to 8%, saline solution with concentration from 0 to 22%, and dried (10ppm), ambient (39ppm) and wet (68ppm) aviation fuels were used in experiments. The corresponding water activities are measured as 1.0 to 0.99 for sugar solution, 1.0 to 0.86 for saline solution, and 0.15, 0.57 and 1.0 for the aviation fuel samples. The water content in the measured samples ranges from 100% (pure water) to 10 ppm (dried aviation fuel). The PMMA based optical fiber grating exhibits good sensitivity and consistent response, and Bragg wavelength shifts as large as 3.4 nm when the sensor is transferred from dry fuel to wet fuel.

Behavior of uranium under conditions of interaction of rocks and ores with subsurface water

NASA Astrophysics Data System (ADS)

Omel'Yanenko, B. I.; Petrov, V. A.; Poluektov, V. V.

2007-10-01

The behavior of uranium during interaction of subsurface water with crystalline rocks and uranium ores is considered in connection with the problem of safe underground insulation of spent nuclear fuel (SNF). Since subsurface water interacts with crystalline rocks formed at a high temperature, the mineral composition of these rocks and uranium species therein are thermodynamically unstable. Therefore, reactions directed toward the establishment of equilibrium proceed in the water-rock system. At great depths that are characterized by hindered water exchange, where subsurface water acquires near-neutral and reducing properties, the interaction is extremely sluggish and is expressed in the formation of micro- and nanoparticles of secondary minerals. Under such conditions, the slow diffusion redistribution of uranium with enrichment in absorbed forms relative to all other uranium species is realized as well. The products of secondary alteration of Fe- and Ti-bearing minerals serve as the main sorbents of uranium. The rate of alteration of minerals and conversion of uranium species into absorbed forms is slow, and the results of these processes are insignificant, so that the rocks and uranium species therein may be regarded as unaltered. Under reducing conditions, subsurface water is always saturated with uranium. Whether water interacts with rock or uranium ore, the equilibrium uranium concentration in water is only ≤10-8 mol/l. Uraninite ore under such conditions always remains stable irrespective of its age. The stability conditions of uranium ore are quite suitable for safe insulation of SNF, which consists of 95% uraninite (UO2) and is a confinement matrix for all other radionuclides. The disposal of SNF in massifs of crystalline rocks at depths below 500 m, where reducing conditions are predominant, is a reliable guarantee of high SNF stability. Under oxidizing conditions of the upper hydrodynamic zone, the rate of interaction of rocks with subsurface water

Water quality in simulated eutrophic shallow lakes in the presence of periphyton under different flow conditions.

PubMed

Chen, Shu; Yang, Guolu; Lu, Jing; Wang, Lei

2018-02-01

Although the effects of periphyton on water quality and its relationship with flow conditions have been studied by researchers, our understanding about their combined action in eutrophic shallow lakes is poor. In this research, four aquatic model ecosystems with different water circulation rates and hydraulic conditions were constructed to investigate the effect of periphyton and flow condition on water quality. The concentrations of NH 4 + , TP, and chlorophyll-a and flow conditions were determined. The results show that, as a result of the rising nutrient level at the early stage and the decline in the lower limit, the presence of periphyton can make the ecosystem adaptable to a wider range of nutrients concentration. In terms of the flow condition, the circulation rate and hydraulic condition are influential factors for aquatic ecosystem. Higher circulation rate in the ecosystem, on one hand, facilitates the metabolism by accelerating nutrient cycling which is beneficial to water quality; on the other hand, high circulation rate leads to the nutrient lower limit rising which is harmful to water quality improvement. At low velocities, slight differences in hydraulic conditions, vertical velocity gradient and turbulence intensity gradient could affect the quantity of phytoplankton. Our study suggests that, considering environmental effect of periphyton, flow conditions and their combined action is essential for water quality improvement and ecological restoration in eutrophic shallow lakes.

Use of Linear Prediction Uncertainty Analysis to Guide Conditioning of Models Simulating Surface-Water/Groundwater Interactions

NASA Astrophysics Data System (ADS)

Hughes, J. D.; White, J.; Doherty, J.

2011-12-01

Linear prediction uncertainty analysis in a Bayesian framework was applied to guide the conditioning of an integrated surface water/groundwater model that will be used to predict the effects of groundwater withdrawals on surface-water and groundwater flows. Linear prediction uncertainty analysis is an effective approach for identifying (1) raw and processed data most effective for model conditioning prior to inversion, (2) specific observations and periods of time critically sensitive to specific predictions, and (3) additional observation data that would reduce model uncertainty relative to specific predictions. We present results for a two-dimensional groundwater model of a 2,186 km2 area of the Biscayne aquifer in south Florida implicitly coupled to a surface-water routing model of the actively managed canal system. The model domain includes 5 municipal well fields withdrawing more than 1 Mm3/day and 17 operable surface-water control structures that control freshwater releases from the Everglades and freshwater discharges to Biscayne Bay. More than 10 years of daily observation data from 35 groundwater wells and 24 surface water gages are available to condition model parameters. A dense parameterization was used to fully characterize the contribution of the inversion null space to predictive uncertainty and included bias-correction parameters. This approach allows better resolution of the boundary between the inversion null space and solution space. Bias-correction parameters (e.g., rainfall, potential evapotranspiration, and structure flow multipliers) absorb information that is present in structural noise that may otherwise contaminate the estimation of more physically-based model parameters. This allows greater precision in predictions that are entirely solution-space dependent, and reduces the propensity for bias in predictions that are not. Results show that application of this analysis is an effective means of identifying those surface-water and

Orbital apocenter is not a sufficient condition for HST/STIS detection of Europa’s water vapor aurora

PubMed Central

Retherford, Kurt D.; Saur, Joachim; Strobel, Darrell F.; Feldman, Paul D.; McGrath, Melissa A.; Nimmo, Francis

2014-01-01

We report far-ultraviolet observations of Jupiter’s moon Europa taken by Space Telescope Imaging Spectrograph (STIS) of the Hubble Space Telescope (HST) in January and February 2014 to test the hypothesis that the discovery of a water vapor aurora in December 2012 by local hydrogen (H) and oxygen (O) emissions with the STIS originated from plume activity possibly correlated with Europa’s distance from Jupiter through tidal stress variations. The 2014 observations were scheduled with Europa near the apocenter similar to the orbital position of its previous detection. Tensile stresses on south polar fractures are expected to be highest in this orbital phase, potentially maximizing the probability for plume activity. No local H and O emissions were detected in the new STIS images. In the south polar region where the emission surpluses were observed in 2012, the brightnesses are sufficiently low in the 2014 images to be consistent with any H2O abundance from (0–5)×1015 cm−2. Large high-latitude plumes should have been detectable by the STIS, independent of the observing conditions and geometry. Because electron excitation of water vapor remains the only viable explanation for the 2012 detection, the new observations indicate that although the same orbital position of Europa for plume activity may be a necessary condition, it is not a sufficient condition. However, the December 2012 detection of coincident HI Lyman-α and OI 1304-Å emission surpluses in an ∼200-km high region well separated above Europa’s limb is a firm result and not invalidated by our 2014 STIS observations. PMID:25404343

The fate of carbon dioxide in water-rich fluids under extreme conditions

PubMed Central

Pan, Ding; Galli, Giulia

2016-01-01

Investigating the fate of dissolved carbon dioxide under extreme conditions is critical to understanding the deep carbon cycle in Earth, a process that ultimately influences global climate change. We used first-principles molecular dynamics simulations to study carbonates and carbon dioxide dissolved in water at pressures (P) and temperatures (T) approximating the conditions of Earth’s upper mantle. Contrary to popular geochemical models assuming that molecular CO2(aq) is the major carbon species present in water under deep Earth conditions, we found that at 11 GPa and 1000 K, carbon exists almost entirely in the forms of solvated carbonate (CO32−) and bicarbonate (HCO3−) ions and that even carbonic acid [H2CO3(aq)] is more abundant than CO2(aq). Furthermore, our simulations revealed that ion pairing between Na+ and CO32−/HCO3− is greatly affected by P-T conditions, decreasing with increasing pressure at 800 to 1000 K. Our results suggest that in Earth’s upper mantle, water-rich geofluids transport a majority of carbon in the form of rapidly interconverting CO32− and HCO3− ions, not solvated CO2(aq) molecules. PMID:27757424

The fate of carbon dioxide in water-rich fluids under extreme conditions.

PubMed

Pan, Ding; Galli, Giulia

2016-10-01

Investigating the fate of dissolved carbon dioxide under extreme conditions is critical to understanding the deep carbon cycle in Earth, a process that ultimately influences global climate change. We used first-principles molecular dynamics simulations to study carbonates and carbon dioxide dissolved in water at pressures ( P ) and temperatures ( T ) approximating the conditions of Earth's upper mantle. Contrary to popular geochemical models assuming that molecular CO 2 (aq) is the major carbon species present in water under deep Earth conditions, we found that at 11 GPa and 1000 K, carbon exists almost entirely in the forms of solvated carbonate ([Formula: see text]) and bicarbonate ([Formula: see text]) ions and that even carbonic acid [H 2 CO 3 (aq)] is more abundant than CO 2 (aq). Furthermore, our simulations revealed that ion pairing between Na + and [Formula: see text]/[Formula: see text] is greatly affected by P - T conditions, decreasing with increasing pressure at 800 to 1000 K. Our results suggest that in Earth's upper mantle, water-rich geofluids transport a majority of carbon in the form of rapidly interconverting [Formula: see text] and [Formula: see text] ions, not solvated CO 2 (aq) molecules.

Quality-assurance plan for water-quality activities in the U.S. Geological Survey Washington Water Science Center

USGS Publications Warehouse

Conn, Kathleen E.; Huffman, Raegan L.; Barton, Cynthia

2017-05-08

In accordance with guidelines set forth by the Office of Water Quality in the Water Mission Area of the U.S. Geological Survey, a quality-assurance plan has been created for use by the Washington Water Science Center (WAWSC) in conducting water-quality activities. This qualityassurance plan documents the standards, policies, and procedures used by the WAWSC for activities related to the collection, processing, storage, analysis, and publication of water-quality data. The policies and procedures documented in this quality-assurance plan for water-quality activities complement the quality-assurance plans for surface-water and groundwater activities at the WAWSC.

THE WATER-WATER CYCLE IN CHLOROPLASTS: Scavenging of Active Oxygens and Dissipation of Excess Photons.

PubMed

Asada, Kozi

1999-06-01

Photoreduction of dioxygen in photosystem I (PSI) of chloroplasts generates superoxide radicals as the primary product. In intact chloroplasts, the superoxide and the hydrogen peroxide produced via the disproportionation of superoxide are so rapidly scavenged at the site of their generation that the active oxygens do not inactivate the PSI complex, the stromal enzymes, or the scavenging system itself. The overall reaction for scavenging of active oxygens is the photoreduction of dioxygen to water via superoxide and hydrogen peroxide in PSI by the electrons derived from water in PSII, and the water-water cycle is proposed for these sequences. An overview is given of the molecular mechanism of the water-water cycle and microcompartmentalization of the enzymes participating in it. Whenever the water-water cycle operates properly for scavenging of active oxygens in chloroplasts, it also effectively dissipates excess excitation energy under environmental stress. The dual functions of the water-water cycle for protection from photoinihibition are discussed.

Cytokinin Activity in Water-stressed Shoots 1

PubMed Central

Itai, Chanan; Vaadia, Yoash

1971-01-01

Water stress applied to the plant shoot through enhanced evaporative demands reduced cytokinin activity in extracts of xylem exudate and leaves. This reduction resembled the changes in cytokinin activity caused by water stress applied to the root. Cytokinin activity in detached wilting leaves decreased rapidly. Recovery took place after several hours in a humid chamber. Experiments with 14C-kinetin indicated that the mechanism of the inactivation and its reversal involve a chemical transformation of the cytokinin molecule. PMID:16657585

Evaporation Rates for Liquid Water and Ice Under Current Martian Conditions

NASA Technical Reports Server (NTRS)

Sears, D. W. G.; Moore, S. R.; Meier, A.; Chittenden, J.; Kareev, M.; Farmer, C. B.

2004-01-01

A number of studies have been concerned with the evaporation rates under martian conditions in order to place limits on the possible survival time of both liquid water and ice exposed on the surface of Mars. Such studies also aid in assessing the efficacy of an overlying layer of dust or loose regolith material in providing a barrier to free evaporation and thus prolong the lifetime of water in locations where its availability to putative living organisms would be significant. A better quantitative understanding of the effects of phase changes of water in the near surface environment would also aid the evaluation of the possible role of water in the formation of currently observed features, such as gullies in cliff walls and relatively short-term changes in the albedo of small surface areas ('dark stains'). Laboratory measurements aimed at refinement of our knowledge of these values are described here. The establishment of accurate values for evaporation rates and their dependence on the physical conditions of temperature, pressure and energy input, is an important benchmark for the further investigation of the efficacy of barriers to free evaporation in providing a prolonged period of survival of the water, particularly as a liquid.

Monochloramine Cometabolism by Mixed-Culture Nitrifiers under Drinking Water Conditions

EPA Science Inventory

The current research investigated monochloramine cometabolism by nitrifying mixed cultures grown under drinking water relevant conditions and harvested from sand-packed reactors before conducting suspended growth batch kinetic experiments. Three batch reactors were used in each ...

CURRENT CONDITIONS AND RESIDENCE PREFERENCES OR CITIZENS' PERCEPTIONS ON NONCONVENTIONAL WATER RESOURCES

NASA Astrophysics Data System (ADS)

Tsuzuki, Yoshiaki; Aramaki, Toshiya

Preferences or perceptions of ordinary citizens on three kinds of nonconventional water resources including rainwater, permissible groundwater exuding to underground railway stations and tunnels and reclaimed wastewater were investigated by use of the Internet survey method. The survey results were analysed with analytical hierar chal process (AHP) and willingness to pay (WTP). Weight vectors of natural environment and people's lives were found larger than other three first order evaluation conditions, society, economics and technology. The order of the weight vector values for the three water resources were rainwater, reclaimed wastewater and permissible groundwater. That for the five water usages were agricultural and horticulture water, water storage in preparation for disaster, toilet flushing water, environment water and sprinkler water for washing road and cooling atmosphere temperature. The difference between toilet flushing water and environment water was not significant by 5% significance. The analyzed data showed that differences between the weight vector values of the alternatives (water resources and their usages) became small by increasing the number of the evaluation conditions, which would be a topic to be resolved for AHP application to actual public projects. For water resources, WTP with public budgets was Japanese Yen (JY) 53,100-55,100 person-1 year-1, and WTP with private finances was JY 19,100-20,800 person-1 year-1. For water usages, public WTP was JY 20,400-47,200 person-1 year-1 and private WTP was JY 8,400-16,000 person-1 year-1. The orders of WTP values were similar to the orders of the weight vector values for both water resources and their usages obtained by the AHP analysis. Effective dissemination subjects and objects of the nonconventional water resources and their usages were extracted by the analysis for attributes including sex, age, living area, occupation and education.

The contribution of weak CAM to the photosynthetic metabolic activities of a bromeliad species under water deficit.

PubMed

Pikart, Filipe C; Marabesi, Mauro A; Mioto, Paulo T; Gonçalves, Ana Z; Matiz, Alejandra; Alves, Frederico R R; Mercier, Helenice; Aidar, Marcos P M

2018-02-01

The Crassulacean acid metabolism (CAM) can be a transitory strategy for saving water during unfavourable conditions, like a dry season. In some cases, CAM can also contribute to the maintenance of photosynthetic integrity, even if carbon gain and growth are impaired. CAM occurs in different intensities, being stronger or weaker depending on the degree of nocturnal malic acid accumulation. For example, Guzmania monostachia is an epiphytic tank bromeliad that shows an increase in its nocturnal organic acid accumulation and a variable CAM behaviour when exposed to water deficit. In this context, this study aimed at investigating whether the weak CAM displayed by this species may mitigate the harmful effects of water limitation on its photosynthetic activity. To this, bromeliads were submitted to well-watered and water deficit conditions. Guzmania monostachia plants under water deficiency conditions showed a reduction on atmospheric carbon assimilation without exhibiting changes in PSII integrity and carbohydrate production while showed an increase in nocturnal malic acid accumulation. Additionally, spots with high PSII efficiency in the leaf portion with a greater nocturnal malic acid accumulation were observed in plants exposed to water shortage conditions. These high-efficiency spots might be associated with a greater malate decarboxylation capacity. Also, the malic acid contributed to approximately 50% of the total carbon assimilated under water deficit. These results suggest that weak CAM may participate in photo-protection and it appears to meaningfully contribute to the overall carbon balance, being an important metabolic strategy to maintain plant fitness during water deficit periods. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Water Quality Conditions in Upper Klamath and Agency Lakes, Oregon, 2006

USGS Publications Warehouse

Lindenberg, Mary K.; Hoilman, Gene; Wood, Tamara M.

2008-01-01

The U.S. Geological Survey Upper Klamath Lake water quality monitoring program gathered information from multiparameter continuous water quality monitors, physical water samples, dissolved oxygen production and consumption experiments, and meteorological stations during the June-October 2006 field season. The 2006 study area included Agency Lake and all of Upper Klamath Lake. Seasonal patterns in water quality were similar to those observed in 2005, the first year of the monitoring program, and were closely related to bloom dynamics of the cyanobacterium (blue-green alga) Aphanizomenon flos-aquae (AFA) in the two lakes. High dissolved oxygen and pH conditions in both lakes before the bloom declined in July, which coincided with seasonal high temperatures and resulted in seasonal lows in dissolved oxygen and decreased pH. Dissolved oxygen and pH in Upper Klamath and Agency Lakes increased again after the bloom recovered. Seasonal low dissolved oxygen and decreased pH coincided with seasonal highs in ammonia and orthophosphate concentrations. Seasonal maximum daily average temperatures were higher and minimum dissolved oxygen concentrations were lower in 2006 than in 2005. Conditions potentially harmful to fish were influenced by seasonal patterns in bloom dynamics and bathymetry. Potentially harmful low dissolved oxygen and high un-ionized ammonia concentrations occurred mostly at the deepest sites in the Upper Klamath Lake during late July, coincident with a bloom decline. Potentially harmful pH conditions occurred mostly at sites outside the deepest parts of the lake in July and September, coincident with a heavy bloom. Instances of possible gas bubble formation, inferred from dissolved oxygen data, were estimated to occur frequently in shallow areas of Upper Klamath and Agency Lakes simultaneously with potentially harmful pH conditions. Comparison of the data from monitors in nearshore areas and monitors near the surface of the water column in the open waters of

Water resources activities in Kentucky, 1993-94

USGS Publications Warehouse

Maglothin, L. S.; Forbes, R.W.

1994-01-01

The U.S. Geological Survey (USGS) is the principal Federal water-resources data collection and investigation agency. Through the Water Resources Division District Office in Kentucky, the USGS investigates the occurrence, distribution, quantity, movement, and chemical and biological quality of surface and ground water in the State. The mission of this program is to collect, interpret, and publish information on water resources. Almost all research and data collection is a cooperative effort in which planning and financial support are shared by State and local agencies and governments. Other activities are funded by other Federal agencies or by direct Congressional appropriation. This report is intended to inform the public and cooperating agencies, vitally interested in the water resources of Kentucky, as to the current status of the Distfict's data collection and investigation program. Included in the report are summaries of water-resources activities in Kentucky conducted by the USGS. Also included is a description of the USGS mission and program, District organization, funding sources and cooperating agencies, and a list of USGS publications relevant to the water resources of the State.

Bacterial Contamination on Household Toys and Association with Water, Sanitation and Hygiene Conditions in Honduras

PubMed Central

Stauber, Christine E.; Walters, Adam; de Aceituno, Anna M. Fabiszewski; Sobsey, Mark D.

2013-01-01

There is growing evidence that household water treatment interventions improve microbiological water quality and reduce diarrheal disease risk. Few studies have examined, however, the impact of water treatment interventions on household-level hygiene and sanitation. This study examined the association of four water and sanitation conditions (access to latrines, improved sanitation, improved water and the plastic biosand filter) on the levels of total coliforms and E. coli on existing and introduced toys during an on-going randomized controlled trial of the plastic biosand filter (plastic BSF). The following conditions were associated with decreased bacterial contamination on children’s toys: access to a latrine, access to improved sanitation and access to the plastic BSF. Overall, compared to existing toys, introduced toys had significantly lower levels of both E. coli and total coliforms. Results suggest that levels of fecal indicator bacteria contamination on children’s toys may be associated with access to improved water and sanitation conditions in the home. In addition, the fecal indicator bacteria levels on toys probably vary with duration in the household. Additional information on how these toys become contaminated is needed to determine the usefulness of toys as indicators or sentinels of water, sanitation and hygiene conditions, behaviors and risks. PMID:23598302

Bacterial contamination on household toys and association with water, sanitation and hygiene conditions in Honduras.

PubMed

Stauber, Christine E; Walters, Adam; Fabiszewski de Aceituno, Anna M; Sobsey, Mark D

2013-04-18

There is growing evidence that household water treatment interventions improve microbiological water quality and reduce diarrheal disease risk. Few studies have examined, however, the impact of water treatment interventions on household-level hygiene and sanitation. This study examined the association of four water and sanitation conditions (access to latrines, improved sanitation, improved water and the plastic biosand filter) on the levels of total coliforms and E. coli on existing and introduced toys during an on-going randomized controlled trial of the plastic biosand filter (plastic BSF). The following conditions were associated with decreased bacterial contamination on children's toys: access to a latrine, access to improved sanitation and access to the plastic BSF. Overall, compared to existing toys, introduced toys had significantly lower levels of both E. coli and total coliforms. Results suggest that levels of fecal indicator bacteria contamination on children's toys may be associated with access to improved water and sanitation conditions in the home. In addition, the fecal indicator bacteria levels on toys probably vary with duration in the household. Additional information on how these toys become contaminated is needed to determine the usefulness of toys as indicators or sentinels of water, sanitation and hygiene conditions, behaviors and risks.

Definition of boundary and initial conditions in the analysis of saturated ground-water flow systems - An introduction

USGS Publications Warehouse

Franke, O. Lehn; Reilly, Thomas E.; Bennett, Gordon D.

1987-01-01

Accurate definition of boundary and initial conditions is an essential part of conceptualizing and modeling ground-water flow systems. This report describes the properties of the seven most common boundary conditions encountered in ground-water systems and discusses major aspects of their application. It also discusses the significance and specification of initial conditions and evaluates some common errors in applying this concept to ground-water-system models. An appendix is included that discusses what the solution of a differential equation represents and how the solution relates to the boundary conditions defining the specific problem. This report considers only boundary conditions that apply to saturated ground-water systems.

Evaluation of future base-flow water-quality conditions in the Hillsborough River, Florida

USGS Publications Warehouse

Fernandez, Mario; Goetz, C.L.; Miller, J.E.

1984-01-01

A one-dimensional, steady-state, water-quality model was developed for a 30.0 mile reach of the Hillsborough River to evaluate water-quality conditions to be expected from future development. The model was calibrated and verified using data collected under critical base-flow conditions in April and December 1978. Dissolved organic nitrogen, nitrate nitrogen, and total and fecal coliforms were modeled for most of the study reach. Model results were used to evaluate the impacts of two typical housing developments on water-quality conditions in Tampa Reservoir. One development is located in the Cypress Creek basin and the other near the upper end of the study reach. Model results show development in the Hillsborough River basin may cause increased total and fecal coliform conditions. Simulated total coliforms at the Tampa water treatment plant for 1-, 3-, and 5-square-mile developments located in the Cypress Creek basin were 3,000, 5,400, and 8,300 colonies per 100 milliliters. Similar developments, however, located near the upper end of the study reach were 2,000, 3,600, and 5,100 colonies per 100 milliliters. Simulated fecal coliforms were 360, 700, and 100 and 180, 350, and 510 colonies per 100 milliliters, respectively. Other constituents modeled showed only minor increases in concentrations. (USGS)

Vulval skin conditions: disease activity and quality of life.

PubMed

Lawton, Sandra; Littlewood, Sheelagh

2013-04-01

Chronic vulval skin conditions are known to cause a significant reduction in the quality of life. Validated scales exist to measure the disease impact of general dermatologic conditions; however, none have been specifically derived to assess vulval disease. This study aimed to identify what symptoms and aspects of their lives are important for women with vulval skin conditions and to assess their usefulness in developing an assessment measure for monitoring disease activity and quality of life in women with vulval skin conditions. Participants were female patients attending a specialist vulval dermatology clinic at a tertiary referral center. Ten patients with a variety vulval skin conditions were interviewed to gain their experiences of living with a vulval skin condition. Using qualitative semistructured interviews, patients were asked open-ended questions about aspects of their disease that have affected them. These included the following: daily activities and social activities, physical functions, sexual activities, mobility, relationships, and an understanding of their vulval condition. Data was recorded, transcribed, and then analyzed thematically with all aspects regarding quality of life and symptoms identified. Results are presented according to common themes identified, specifically physical symptoms, body image, the impact of the condition on sexual and physical function, issues affecting daily activities, and the journey traveled when accessing medical care. This qualitative study adds to the evidence that chronic vulval conditions are distressing and cause significant morbidity. It highlights further the need to devise a validated questionnaire which can be used in clinical practice looking specifically at disease impact and quality of life. It can only enhance the clinical consultation and facilitate discussion which is disease and person specific.

Water in the Active Site of Ketosteroid Isomerase

PubMed Central

Hanoian, Philip; Hammes-Schiffer, Sharon

2011-01-01

Classical molecular dynamics simulations were utilized to investigate the structural and dynamical properties of water in the active site of ketosteroid isomerase (KSI) to provide insight into the role of these water molecules in the enzyme-catalyzed reaction. This reaction is thought to proceed via a dienolate intermediate that is stabilized by hydrogen bonding with residues Tyr16 and Asp103. A comparative study was performed for the wild-type (WT) KSI and the Y16F, Y16S, and Y16F/Y32F/Y57F (FFF) mutants. These systems were studied with three different bound ligands: equilenin, which is an intermediate analog, and the intermediate states of two steroid substrates. Several distinct water occupation sites were identified in the active site of KSI for the WT and mutant systems. Three additional sites were identified in the Y16S mutant that were not occupied in WT KSI or the other mutants studied. The number of water molecules directly hydrogen bonded to the ligand oxygen was approximately two waters in the Y16S mutant, one water in the Y16F and FFF mutants, and intermittent hydrogen bonding of one water molecule in WT KSI. The molecular dynamics trajectories of the Y16F and FFF mutants reproduced the small conformational changes of residue 16 observed in the crystal structures of these two mutants. Quantum mechanical/molecular mechanical calculations of 1H NMR chemical shifts of the protons in the active site hydrogen-bonding network suggest that the presence of water in the active site does not prevent the formation of short hydrogen bonds with far-downfield chemical shifts. The molecular dynamics simulations indicate that the active site water molecules exchange much more frequently for WT KSI and the FFF mutant than for the Y16F and Y16S mutants. This difference is most likely due to the hydrogen-bonding interaction between Tyr57 and an active site water molecule that is persistent in the Y16F and Y16S mutants but absent in the FFF mutant and significantly less

A water activity based model of heterogeneous ice nucleation kinetics for freezing of water and aqueous solution droplets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Knopf, Daniel A.; Alpert, Peter A.

Immersion freezing of water and aqueous solutions by particles acting as ice nuclei (IN) is a common process of heterogeneous ice nucleation which occurs in many environments, especially in the atmosphere where it results in the glaciation of clouds. Here we experimentally show, using a variety of IN types suspended in various aqueous solutions, that immersion freezing temperatures and kinetics can be described solely by temperature, T, and solution water activity, aw, which is the ratio of the vapour pressure of the solution and the saturation water vapour pressure under the same conditions and, in equilibrium, equivalent to relative humiditymore » (RH). This allows the freezing point and corresponding heterogeneous ice nucleation rate coefficient, Jhet, to be uniquely expressed by T and aw, a result we term the aw based immersion freezing model (ABIFM). This method is independent of the nature of the solute and accounts for several varying parameters, including cooling rate and IN surface area, while providing a holistic description of immersion freezing and allowing prediction of freezing temperatures, Jhet, frozen fractions, ice particle production rates and numbers. Our findings are based on experimental freezing data collected for various IN surface areas, A, and cooling rates, r, of droplets variously containing marine biogenic material, two soil humic acids, four mineral dusts, and one organic monolayer acting as IN. For all investigated IN types we demonstrate that droplet freezing temperatures increase as A increases. Similarly, droplet freezing temperatures increase as the cooling rate decreases. The log 10(J het) values for the various IN types derived exclusively by T and aw, provide a complete description of the heterogeneous ice nucleation kinetics. Thus, the ABIFM can be applied over the entire range of T, RH, total particulate surface area, and cloud activation timescales typical of atmospheric conditions. Finally, we demonstrate that ABIFM can

A water activity based model of heterogeneous ice nucleation kinetics for freezing of water and aqueous solution droplets.

PubMed

Knopf, Daniel A; Alpert, Peter A

2013-01-01

Immersion freezing of water and aqueous solutions by particles acting as ice nuclei (IN) is a common process of heterogeneous ice nucleation which occurs in many environments, especially in the atmosphere where it results in the glaciation of clouds. Here we experimentally show, using a variety of IN types suspended in various aqueous solutions, that immersion freezing temperatures and kinetics can be described solely by temperature, T, and solution water activity, a(w), which is the ratio of the vapour pressure of the solution and the saturation water vapour pressure under the same conditions and, in equilibrium, equivalent to relative humidity (RH). This allows the freezing point and corresponding heterogeneous ice nucleation rate coefficient, J(het), to be uniquely expressed by T and a(w), a result we term the a(w) based immersion freezing model (ABIFM). This method is independent of the nature of the solute and accounts for several varying parameters, including cooling rate and IN surface area, while providing a holistic description of immersion freezing and allowing prediction of freezing temperatures, J(het), frozen fractions, ice particle production rates and numbers. Our findings are based on experimental freezing data collected for various IN surface areas, A, and cooling rates, r, of droplets variously containing marine biogenic material, two soil humic acids, four mineral dusts, and one organic monolayer acting as IN. For all investigated IN types we demonstrate that droplet freezing temperatures increase as A increases. Similarly, droplet freezing temperatures increase as the cooling rate decreases. The log10(J(het)) values for the various IN types derived exclusively by Tand a(w), provide a complete description of the heterogeneous ice nucleation kinetics. Thus, the ABIFM can be applied over the entire range of T, RH, total particulate surface area, and cloud activation timescales typical of atmospheric conditions. Lastly, we demonstrate that ABIFM can

A water activity based model of heterogeneous ice nucleation kinetics for freezing of water and aqueous solution droplets

DOE PAGES

Knopf, Daniel A.; Alpert, Peter A.

2013-04-24

Immersion freezing of water and aqueous solutions by particles acting as ice nuclei (IN) is a common process of heterogeneous ice nucleation which occurs in many environments, especially in the atmosphere where it results in the glaciation of clouds. Here we experimentally show, using a variety of IN types suspended in various aqueous solutions, that immersion freezing temperatures and kinetics can be described solely by temperature, T, and solution water activity, aw, which is the ratio of the vapour pressure of the solution and the saturation water vapour pressure under the same conditions and, in equilibrium, equivalent to relative humiditymore » (RH). This allows the freezing point and corresponding heterogeneous ice nucleation rate coefficient, Jhet, to be uniquely expressed by T and aw, a result we term the aw based immersion freezing model (ABIFM). This method is independent of the nature of the solute and accounts for several varying parameters, including cooling rate and IN surface area, while providing a holistic description of immersion freezing and allowing prediction of freezing temperatures, Jhet, frozen fractions, ice particle production rates and numbers. Our findings are based on experimental freezing data collected for various IN surface areas, A, and cooling rates, r, of droplets variously containing marine biogenic material, two soil humic acids, four mineral dusts, and one organic monolayer acting as IN. For all investigated IN types we demonstrate that droplet freezing temperatures increase as A increases. Similarly, droplet freezing temperatures increase as the cooling rate decreases. The log 10(J het) values for the various IN types derived exclusively by T and aw, provide a complete description of the heterogeneous ice nucleation kinetics. Thus, the ABIFM can be applied over the entire range of T, RH, total particulate surface area, and cloud activation timescales typical of atmospheric conditions. Finally, we demonstrate that ABIFM can

An intuitionistic fuzzy multi-objective non-linear programming model for sustainable irrigation water allocation under the combination of dry and wet conditions

NASA Astrophysics Data System (ADS)

Li, Mo; Fu, Qiang; Singh, Vijay P.; Ma, Mingwei; Liu, Xiao

2017-12-01

Water scarcity causes conflicts among natural resources, society and economy and reinforces the need for optimal allocation of irrigation water resources in a sustainable way. Uncertainties caused by natural conditions and human activities make optimal allocation more complex. An intuitionistic fuzzy multi-objective non-linear programming (IFMONLP) model for irrigation water allocation under the combination of dry and wet conditions is developed to help decision makers mitigate water scarcity. The model is capable of quantitatively solving multiple problems including crop yield increase, blue water saving, and water supply cost reduction to obtain a balanced water allocation scheme using a multi-objective non-linear programming technique. Moreover, it can deal with uncertainty as well as hesitation based on the introduction of intuitionistic fuzzy numbers. Consideration of the combination of dry and wet conditions for water availability and precipitation makes it possible to gain insights into the various irrigation water allocations, and joint probabilities based on copula functions provide decision makers an average standard for irrigation. A case study on optimally allocating both surface water and groundwater to different growth periods of rice in different subareas in Heping irrigation area, Qing'an County, northeast China shows the potential and applicability of the developed model. Results show that the crop yield increase target especially in tillering and elongation stages is a prevailing concern when more water is available, and trading schemes can mitigate water supply cost and save water with an increased grain output. Results also reveal that the water allocation schemes are sensitive to the variation of water availability and precipitation with uncertain characteristics. The IFMONLP model is applicable for most irrigation areas with limited water supplies to determine irrigation water strategies under a fuzzy environment.

Treatment of Aqueous Film-Forming Foam by Heat-Activated Persulfate Under Conditions Representative of In Situ Chemical Oxidation

PubMed Central

2017-01-01

Poly- and perfluoroalkyl substances (PFASs) have been detected in an increasing number of water supplies. In many instances, the contamination is associated with the use of PFAS-containing aqueous film-forming foams (AFFF) in firefighting activities. To investigate the potential for remediating AFFF contamination in groundwater with heat-activated persulfate, PFAS oxidation and the generation of transformation products was evaluated under well-controlled conditions. Fluorotelomer- and perfluoroalkyl sulfonamide-based polyfluorinated compounds were transformed to perfluorinated carboxylic acids, which underwent further degradation under acidic conditions produced after persulfate decomposed. The presence of aquifer sediments decreased the efficiency of the remedial process but did not alter the transformation pathways. At high concentrations, the presence of organic solvents, such as those present in AFFF formulations, inhibited transformation of a representative perfluorinated compound, perfluorooctanoic acid. Heat-activated persulfate did not transform perfluorooctanesulfonic acid or perfluorohexanesulfonic acid under any conditions. Despite challenges associated with the creation of acidic conditions in the subsurface, the potential for generation of undesirable transformation products, and the release of toxic metals, heat-activated persulfate may be a useful in situ treatment for sites contaminated with polyfluoroalkyl substances and perfluorocarboxylic acids. PMID:29164864

Positive impact of bio-stimulators on growth and physiological activity of willow in climate change conditions

NASA Astrophysics Data System (ADS)

Piotrowski, Krzysztof; Romanowska-Duda, Zdzisława

2018-04-01

The aim of this research was to evaluate the physiological activity and growth of willow (Salix viminalis L.) plants cultivated under the conditions of adverse temperature and soil moisture content, and to assess the effect of the foliar application of Biojodis (1.0%) and Asahi SL (0.03%) bio-stimulators, or a mixture of Microcistis aeruginosa MKR 0105 and Anabaena PCC 7120 cyanobacteria under such changing growth conditions. The obtained results showed different reactions to the applied constant or periodically changed temperature and soil moisture content. The plants which grew at periodically changed adverse temperature (from -5 to 40oC) or in scantily (20% m.c.) or excessively (60% m.c.) watered soils, grew slowly, in comparison with those growing at 20oC and in optimally moistened soil (30% m.c.). Foliar application of Biojodis and Asahi SL cyanobacteria increased the growth of willow at optimal and adverse temperature or in scantily and excessively moistened soil. The changes in plant growth were associated with the changes in electrolyte leakage, activity of acid or alkaline phosphatases, RNase, index of chlorophyll content in leaves and gas exchange. The above indicates that the foliar application of the studied cyanobacteria and bio-stimulators partly alleviates the harmful impact of adverse temperature and water stress on growth and physiological activity of willow plants

Analysis of the performance and space conditioning impacts of dedicated heat pump water heaters

NASA Astrophysics Data System (ADS)

Morrison, L.; Swisher, J.

The development and testing of the newly-marketed dedicated heat pump water heater (HPWH) are described. This system utilizes an air-to-water heat pump, costs about $1,000 installed, and obtains a coefficient of performance (COP) of about 2.0 in laboratory and field tests. To investigate HPWH performance and space conditioning impacts, a simulation was developed to mode the thermal performance of a residence with resistance baseboard heat, air conditioning, and either heat pump or resistance water heating. The building characteristics are adapted for three U.S. geographical areas (Madison, Wisconsin; Washington, D.C.; and Ft. Worth, Texas), and the system is simulated for a year with typical weather data. The thermal network includes both a house node and a basement node so that the water heating equipment can be simulated in an unconditioned basement in Northern cities and in a conditioned first-floor utility room in Southern cities.

Microbial activity in debris-rich basal ice; adaption to sub-zero, saline conditions

NASA Astrophysics Data System (ADS)

Montross, S. N.; Skidmore, M. L.; Christner, B. C.; Griggs, R.; Tison, J.; Sowers, T. A.

2011-12-01

Polycrystalline ice in glaciers and ice sheets has a high preservation potential for biological material and chemical compounds that can be used to document the presence of active microbial metabolism at sub-zero temperatures. The concentration and isotopic composition of gases, in conjunction with other aqueous chemical species in debris-rich basal glacier ice from Taylor Glacier, Antarctica were used as direct evidence that cells entrained in the ice remain metabolically active at temperatures as low as -17°C, likely in thin films of liquid water along ice crystal and mineral grain boundaries. δ18O2 and δ13CO2 values measured in the ice are consistent with the hypothesis that abrupt changes measured in O2 and CO2 concentrations between debris-rich and debris-poor ice are due to in situ microbial mineralization of organic carbon. Low temperature culture-based experiments conducted using organisms isolated from the ice indicate the ability to respire organic carbon to CO2 under oxic conditions and under anoxic conditions couple carbon mineralization to dissimilatory iron reduction using Fe3+ as an electron acceptor. Microorganisms that are active in the debris-rich basal ice layers in terrestrial polar ice masses need to be adapted to surviving subzero temperatures and saline conditions on extended timescales. Thus these terrestrial glacial systems and the isotopic and geochemical biomarkers therein provide good analogues for guiding exploration and analysis of debris-rich ices in extraterrestrial settings, for example, on Mars.

Recreational use assessment of water-based activities, using time-lapse construction cameras.

PubMed

Sunger, Neha; Teske, Sondra S; Nappier, Sharon; Haas, Charles N

2012-01-01

Recreational exposure to surface waters during periods of increased pathogen concentration may lead to a significantly higher risk of illness. However, estimates of elementary exposure factors necessary to evaluate health risk (i.e., usage distributions and exposure durations) are not available for many non-swimming water-related activities. No prior studies have assessed non-swimming water exposure with respect to factors leading to impaired water quality from increased pathogen concentration, such as weather condition (rain events produce increased runoff and sewer overflows) and type of day (heavy recreational periods). We measured usage patterns and evaluated the effect of weather and type of day at eight water sites located within Philadelphia, by using a novel "time lapse photography" technology during three peak recreational seasons (May-September) 2008-2010. Camera observations validated with simultaneous in-person surveys exhibited a strong correlation (R(2)=0.81 to 0.96) between the two survey techniques, indicating that the application of remote photography in collecting human exposure data was appropriate. Recreational activities usage varied more on a temporal basis than due to inclement weather. Only 14% (6 out of 44) of the site-specific activity combinations showed dry weather preference, whereas 41.5% (17 out of 41) of the combinations indicated greater usage on weekends as compared with weekday. In general, the log normal distribution described the playing and wading duration distribution, while the gamma distribution was the best fit for fishing durations. Remote photography provided unbiased, real-time human exposure data and was less personnel intensive compared with traditional survey methods. However, there are potential limitations associated with remote surveillance data related to its limited view. This is the first study to report that time lapse cameras can be successfully applied to assess water-based human recreational patterns and can

Role of air-water interfaces on retention of viruses under unsaturated conditions

NASA Astrophysics Data System (ADS)

Torkzaban, S.; Hassanizadeh, S. M.; Schijven, J. F.; van den Berg, H. H. J. L.

2006-12-01

We investigated transport of viruses through saturated and unsaturated sand columns. Unsaturated experiments were conducted under conditions of uniform saturation and steady state water flow. The water saturation ranged from 1 to 0.5. Bacteriophages MS2 and ϕX174 were used as surrogates for pathogenic viruses in these studies. Phosphate-buffered solutions with different pH values (7.5, 6.2, 5.5, and 5) were utilized. Virus transport was modeled assuming first-order kinetic adsorption for interactions to the solid-water interface (SWI) and the air-water interface (AWI). Under saturated conditions, virus retention increased as pH decreased, and a one-site kinetic model produced a good fit to the breakthrough curves. Under unsaturated conditions a two-site kinetic model was needed to fit the breakthrough curves satisfactorily. The second site was attributed to the adsorption of phages to the AWI. According to our results, ϕX174 exhibits a high affinity to the AWI at pH values below 6.6 (the isoelectric point of ϕX174). Although it is believed that MS2 is more hydrophobic than ϕX174, MS2 had a lower affinity to the AWI than ϕX174, presumably because of the lower isoelectric point of MS2, which is equal to 3.9. Under unsaturated conditions, viruses captured within the column could be recovered in the column outflow by resaturating and immediately draining the column. Draining columns under saturated conditions, however, did not result in any recovery of viruses. Therefore the recovery can be attributed to the release of viruses adsorbed to the AWI. Our results suggest that electrostatic interactions of viruses with the AWI are much more important than hydrophobicity.

Root morphology, hydraulic conductivity and plant water relations of high-yielding rice grown under aerobic conditions.

PubMed

Kato, Yoichiro; Okami, Midori

2011-09-01

Increasing physical water scarcity is a major constraint for irrigated rice (Oryza sativa) production. 'Aerobic rice culture' aims to maximize yield per unit water input by growing plants in aerobic soil without flooding or puddling. The objective was to determine (a) the effect of water management on root morphology and hydraulic conductance, and (b) their roles in plant-water relationships and stomatal conductance in aerobic culture. Root system development, stomatal conductance (g(s)) and leaf water potential (Ψ(leaf)) were monitored in a high-yielding rice cultivar ('Takanari') under flooded and aerobic conditions at two soil moisture levels [nearly saturated (> -10 kPa) and mildly dry (> -30 kPa)] over 2 years. In an ancillary pot experiment, whole-plant hydraulic conductivity (soil-leaf hydraulic conductance; K(pa)) was measured under flooded and aerobic conditions. Adventitious root emergence and lateral root proliferation were restricted even under nearly saturated conditions, resulting in a 72-85 % reduction in total root length under aerobic culture conditions. Because of their reduced rooting size, plants grown under aerobic conditions tended to have lower K(pa) than plants grown under flooded conditions. Ψ(leaf) was always significantly lower in aerobic culture than in flooded culture, while g(s) was unchanged when the soil moisture was at around field capacity. g(s) was inevitably reduced when the soil water potential at 20-cm depth reached -20 kPa. Unstable performance of rice in water-saving cultivations is often associated with reduction in Ψ(leaf). Ψ(leaf) may reduce even if K(pa) is not significantly changed, but the lower Ψ(leaf) would certainly occur in case K(pa) reduces as a result of lower water-uptake capacity under aerobic conditions. Rice performance in aerobic culture might be improved through genetic manipulation that promotes lateral root branching and rhizogenesis as well as deep rooting.

Application of water footprint in a fertirrigated melon crop under semiarid conditions: A review.

NASA Astrophysics Data System (ADS)

Castellanos Serrano, María Teresa; Requejo Mariscal, María Isabel; Villena Gordo, Raquel; Cartagena Causapé, María Carmen; Arce Martínez, Augusto; Ribas Elcorobarrutia, Francisco; Jesús Cabello Cabello, María; María Tarquis Alfonso, Ana

2015-04-01

In recent times, there has been a major increase in the use of water and fertilizers in order to increase agricultural production, while at the same time there has increased evidence that aquifers are reducing their water level, enriched by nutrient and degraded as a result of pollution. So best management practices are needed for much of cropped, irrigated and fertirrigated land, to avoid contamination of fresh water and groundwater. The concept of "water footprint" (WF) was introduced as an indicator for the total volume of direct and indirect freshwater used, consumed and/or polluted [1]. The WF distinguishes between blue water (volume of surface and groundwater consumed), green water (rain-water consumed), and grey water (volume of freshwater that is required to assimilate the load of pollutants based on existing ambient water quality standards). This study is focused in calculating the crops WF using a real case of study in a fertirrigated melon crop under semiarid conditions which is principally cultivated in the centre of Spain declared vulnerable zone to nitrate pollution by applying the Directive 91/676/CEE. During successive years, a melon crop (Cucumis melo L.) was grown under field conditions applying mineral and organic fertilizers. Different doses of ammonium nitrate were used as well as compost derived from the wine-distillery industry which is relevant in this area. This application help us to review the different concepts in which is based WF. Acknowledgements: This project has been supported by INIA-RTA04-111-C3 and INIA-RTA2010-00110-C03-01. Keywords: Water footprint, nitrogen, fertirrigation, inorganic fertilizers, organic amendments, winery waste, semiarid conditions. [1] Hoekstra, A.Y. 2003. Virtual water trade. Proceedings of the International Expert Meeting on Virtual Water Trade, Delft, The Netherlands, 12-13 December 2002. Value of Water Research Report Series No. 12, UNESCO-IHE, Delft, The Netherlands.

Characterising biofilm development on granular activated carbon used for drinking water production.

PubMed

Gibert, Oriol; Lefèvre, Benoît; Fernández, Marc; Bernat, Xavier; Paraira, Miquel; Calderer, Montse; Martínez-Lladó, Xavier

2013-03-01

Under normal operation conditions, granular activated carbon (GAC) employed in drinking water treatment plants (DWTPs) for natural organic matter (NOM) removal can be colonised by microorganisms which can eventually establish active biofilms. The formation of such biofilms can contribute to NOM removal by biodegradation, but also in clogging phenomena that can make necessary more frequent backwashes. Biofilm occurrence and evolution under full-scale-like conditions (i.e. including periodic backwashing) are still uncertain, and GAC filtration is usually operated with a strong empirical component. The aim of the present study was to assess the formation and growth, if any, of biofilm in a periodically backwashed GAC filter. For this purpose, an on-site pilot plant was assembled and operated to closely mimic the GAC filters installed in the DWTP in Sant Joan Despí (Barcelona, Spain). The study comprised a monitoring of both water and GAC cores withdrawn at various depths and times throughout 1 year operation. The biomass parameters assessed were total cell count by confocal laser scanning microscopy (CLSM), DNA and adenosine triphosphate (ATP). Visual examination of GAC particles was also conducted by high-resolution field emission scanning electron microscopy (FESEM). Additionally, water quality and GAC surface properties were monitored. Results provided insight into the extent and spatial distribution of biofilm within the GAC bed. To sum up, it was found that backwashing could physically detach bacteria from the biofilm, which could however build back up to its pre-backwashing concentration before next backwashing cycle. Copyright © 2012 Elsevier Ltd. All rights reserved.

Optimization of the preparation conditions of ceramic products using drinking water treatment sludges.

PubMed

Zamora, R M Ramirez; Ayala, F Espesel; Garcia, L Chavez; Moreno, A Duran; Schouwenaars, R

2008-11-01

The aim of this work is to optimize, via Response Surface Methodology, the values of the main process parameters for the production of ceramic products using sludges obtained from drinking water treatment in order to valorise them. In the first experimental stage, sludges were collected from a drinking water treatment plant for characterization. In the second stage, trials were carried out to elaborate thin cross-section specimens and fired bricks following an orthogonal central composite design of experiments with three factors (sludge composition, grain size and firing temperature) and five levels. The optimization parameters (Y(1)=shrinking by firing (%), Y(2)=water absorption (%), Y(3)=density (g/cm(3)) and Y(4)=compressive strength (kg/cm(2))) were determined according to standardized analytical methods. Two distinct physicochemical processes were active during firing at different conditions in the experimental design, preventing the determination of a full response surface, which would allow direct optimization of production parameters. Nevertheless, the temperature range for the production of classical red brick was closely delimitated by the results; above this temperature, a lightweight ceramic with surprisingly high strength was produced, opening possibilities for the valorisation of a product with considerably higher added value than what was originally envisioned.

Water-quality and algal conditions in the Clackamas River basin, Oregon, and their relations to land and water management

USGS Publications Warehouse

Carpenter, Kurt D.

2003-01-01

In 1998, the U.S. Geological Survey sampled the Clackamas River, its major tributaries, and reservoirs to characterize basic water quality (nutrients, dissolved oxygen, pH, temperature, and conductance), water quantity (water sources within the basin), and algal conditions (biomass and species composition). Sampling locations reflected the dominant land uses in the basin (forest management, agriculture, and urban development) as well as the influence of hydroelectric projects, to examine how these human influences might be affecting water quality and algal conditions. Nuisance algal growths, with accompanying negative effects on water quality, were observed at several locations in the basin during this study. Algal biomass in the lower Clackamas River reached a maximum of 300 mg/m2 chlorophyll a, producing nuisance algal conditions, including fouled stream channels and daily fluctuations in pH and dissolved oxygen concentrations to levels that did not meet water-quality standards. Algal biomass was highest at sites immediately downstream from the hydroelectric project's reservoirs and/or powerhouses. Nuisance algal conditions also were observed in some of the tributaries, including the North Fork of the Clackamas River, Clear Creek, Rock Creek, and Sieben Creek. High amounts of drifting algae increased turbidity levels in the Clackamas River during June, which coincided with a general increase in the concentration of disinfection by-products found in treated Clackamas River water used for drinking, presumably due to the greater amounts of organic matter in the river. The highest nutrient concentrations were found in the four lowermost tributaries (Deep, Richardson, Rock, and Sieben Creeks), where most of the agriculture and urban development is concentrated. Of these, the greatest load of nutrients came from Deep Creek, which had both high nutrient concentrations and relatively high streamflow. Streams draining forestland in the upper basin (upper Clackamas River

Activity of water in aqueous systems; a frequently neglected property.

PubMed

Blandamer, Mike J; Engberts, Jan B F N; Gleeson, Peter T; Reis, Joao Carlos R

2005-05-01

In this critical review, the significance of the term 'activity' is examined in the context of the properties of aqueous solutions. The dependence of the activity of water(l) at ambient pressure and 298.15 K on solute molality is examined for aqueous solutions containing neutral solutes, mixtures of neutral solutes and salts. Addition of a solute to water(l) always lowers its thermodynamic activity. For some solutes the stabilisation of water(l) is less than and for others more than in the case where the thermodynamic properties of the aqueous solution are ideal. In one approach this pattern is accounted for in terms of hydrate formation. Alternatively the pattern is analysed in terms of the dependence of practical osmotic coefficients on the composition of the aqueous solution and then in terms of solute-solute interactions. For salt solutions the dependence of the activity of water on salt molalities is compared with that predicted by the Debye-Hückel limiting law. The analysis is extended to consideration of the activities of water in binary aqueous mixtures. The dependence on mole fraction composition of the activity of water in binary aqueous mixtures is examined. Different experimental methods for determining the activity of water in aqueous solutions are critically reviewed. The role of water activity is noted in a biochemical context, with reference to the quality, stability and safety of food and finally with regard to health science.

TBA biodegradation in surface-water sediments under aerobic and anaerobic conditions.

PubMed

Bradley, Paul M; Landmeyer, James E; Chapelle, Francis H

2002-10-01

The potential for [U-14C] TBA biodegradation was examined in laboratory microcosms under a range of terminal electron accepting conditions. TBA mineralization to CO2 was substantial in surface-water sediments under oxic, denitrifying, or Mn(IV)-reducing conditions and statistically significant but low under SO4-reducing conditions. Thus, anaerobic TBA biodegradation may be a significant natural attenuation mechanism for TBA in the environment, and stimulation of in situ TBA bioremediation by addition of suitable terminal electron acceptors may be feasible. No degradation of [U-14C] TBA was observed under methanogenic or Fe(III)-reducing conditions.

TBA biodegradation in surface-water sediments under aerobic and anaerobic conditions

USGS Publications Warehouse

Bradley, P.M.; Landmeyer, J.E.; Chapelle, F.H.

2002-01-01

The potential for [U-14C] TBA biodegradation was examined in laboratory microcosms under a range of terminal electron accepting conditions. TBA mineralization to CO2 was substantial in surface-water sediments under oxic, denitrifying, or Mn(IV)-reducing conditions and statistically significant but low under SO4-reducing conditions. Thus, anaerobic TBA biodegradation may be a significant natural attenuation mechanism for TBA in the environment, and stimulation of in situ TBA bioremediation by addition of suitable terminal electron acceptors may be feasible. No degradation of [U-14C] TBA was observed under methanogenic or Fe(III)-reducing conditions.

Purification of trona ores by conditioning with an oil-in-water emulsion

DOEpatents

Miller, J. D.; Wang, Xuming; Li, Minhua

2009-04-14

The present invention is a trona concentrate and a process for floating gangue material from trona ore that comprises forming an emulsion, conditioning the trona ore at a high solids content in a saturated trona suspension, and then floating and removing the gangue material. The process for separating trona from gangue materials in trona ore can include emulsifying an oil in an aqueous solution to form an oil-in-water emulsion. A saturated trona suspension having a high solids content can also be formed having trona of a desired particle size. The undissolved trona in the saturated suspension can be conditioned by mixing the saturated suspension and the oil-in-water emulsion to form a conditioning solid suspension of trona and gangue material. A gas can be injected through the conditioning solid suspension to float the gangue material. Thus, the floated gangue material can be readily separated from the trona to form a purified trona concentrate without requirements of additional heat or other expensive processing steps.

Hydrodynamic boundary condition of water on hydrophobic surfaces.

PubMed

Schaeffel, David; Yordanov, Stoyan; Schmelzeisen, Marcus; Yamamoto, Tetsuya; Kappl, Michael; Schmitz, Roman; Dünweg, Burkhard; Butt, Hans-Jürgen; Koynov, Kaloian

2013-05-01

By combining total internal reflection fluorescence cross-correlation spectroscopy with Brownian dynamics simulations, we were able to measure the hydrodynamic boundary condition of water flowing over a smooth solid surface with exceptional accuracy. We analyzed the flow of aqueous electrolytes over glass coated with a layer of poly(dimethylsiloxane) (advancing contact angle Θ = 108°) or perfluorosilane (Θ = 113°). Within an error of better than 10 nm the slip length was indistinguishable from zero on all surfaces.

Effects of activation energy and activation volume on the temperature-dependent viscosity of water.

PubMed

Kwang-Hua, Chu Rainer

2016-08-01

Water transport in a leaf is vulnerable to viscosity-induced changes. Recent research has suggested that these changes may be partially due to variation at the molecular scale, e.g., regulations via aquaporins, that induce reductions in leaf hydraulic conductance. What are the quantitative as well as qualitative changes in temperature-dependent viscosity due to the role of aquaporins in tuning activation energy and activation volume? Using the transition-state approach as well as the boundary perturbation method, we investigate temperature-dependent viscosity tuned by activation energy and activation volume. To validate our approach, we compare our numerical results with previous temperature-dependent viscosity measurements. The rather good fit between our calculations and measurements confirms our present approach. We have obtained critical parameters for the temperature-dependent (shear) viscosity of water that might be relevant to the increasing and reducing of leaf hydraulic conductance. These parameters are sensitive to temperature, activation energy, and activation volume. Once the activation energy increases, the (shear) viscosity of water increases. Our results also show that as the activation volume increases (say, 10^{-23}m^{3}), the (shear) viscosity of water decreases significantly and the latter induces the enhancing of leaf hydraulic conductance. Within the room-temperature regime, a small increase in the activation energy will increase the water viscosity or reduce the leaf hydraulic conductance. Our approach and results can be applied to diverse plant or leaf attributes.

Exploring New Phenomena in Salty Water Under Planetary Conditions

NASA Astrophysics Data System (ADS)

Goncharov, A. F.; Bove, L. E.; Klotz, S.; Gaal, R.; Saitta, A. M.; Gillet, P.

2015-12-01

Compressed water is overspread on Earth at depth and in the extra-terrestrial space, both interstellar and on outer planets and moons (ice bodies) [1]. Under the conditions experienced in these celestial bodies water displays an incredibly rich phase diagram, including sixteen known crystalline phases, three amorphous ones, and predicted exotic properties like plasticity [2], ionization [3], and superionicity [4]. In this talk I will review our recent experimental results on salty (LiCl, NaCl, MgCl2) water under extreme conditions including: plasticity [5], pressure-induced polyamorphism [6], salty ice crystallization under high pressure [7], and hydrogen bond symmetrisation at Mbar pressures [8]. [1] De Pater, I., and Lissauer, J.J. Planetary Sciences. Cambridge University Press (2004). [2] Wang, Y., Liu, H., et al. Nat. Comm. 563 1566 (2011).[3] Aragones, L., and Vega, C., J. Chem. Phys. 130, 244504 (2009).[4] Cavazzoni, C., et al., Science 283, 44-46 (1999).[5] Bove, L. E., Dreyfus, C. et al., JCP 139, 044501 (2013) ; Ruiz, G. N., Bove, L. E. et al., PCCP 16 18553-18562 (2014).[6] Bove, L. E., Klotz, S. et al., Phys. Rev. Lett. 106, 125701 (2011); Ludl, A. A., Bove, L. E. et al., PCCP 17, 14054 (2015). [7] Klotz, S., Bove, L. E. t al., Nat. Mat. 8, 405 (2009) ; Ludl A. A., Bove, L. E., submitted (2015).[8] Bove L. E. , Gaal, R. et al., PNAS 112, 27 (2015).

The Last Interglacial Labrador Sea: A Pervasive Millennial Oscillation In Surface Water Conditions Without Labrador Sea Water Formation

NASA Astrophysics Data System (ADS)

Hillaire-Marcel, C.; de Vernal, A.

A multi-proxy approach was developed to document secular to millenial changes of potential density in surface, mesopelagic, and bottom waters of the Labrador Sea, thus allowing to reconstruct situations when winter convection with intermediate or deep water formation occurred in the basin. This approach relies on dinocyst-transfer functions providing estimates of sea-surface temperature and salinity that are used to calibrate past-relationships between oxygen 18 contents in calcite and potential density gradients. The oxygen isotope compositions of epipelagic (Globigerina bul- loides), deeper-dwelling (Neogloboquadrina pachyderma, left coiling), and benthic (Uvigerina peregrina and Cibicides wuellerstorfi) foraminifera, then allow to extrap- olate density gradients between the corresponding water layers. This approach has been tested in surface sediments in reference to modern hydrographic conditions at several sites from the NW North Atlantic, then used to reconstruct past conditions from high resolution studies of cores raised from the southern Greenland Rise (off Cape Farewell). Results indicate that the modern-like regime established during the early Holocene and full developed after 7 ka only. It is marked by weak density gradi- ents between the surface and intermediate water masses, allowing winter convection down to a lower pycnocline between intermediate and deep-water masses, thus the formation of intermediate Labrador Sea Water (LSW). Contrasting with the middle to late Holocene situation, since the last interglacial and throughout the last climatic cycle, a single and dense water mass seems to have occupied the water column below a generally low-density surface water layer, thus preventing deep convection. There- fore, the production of LSW seems to be feature specific to the present interglacial interval that could soon cease to exist, due to global warming, as suggested by recent ocean model experiments and by the fact that it never occurred during the

Combined effect of storage temperature and water activity on the antiglycoxidative properties and color of dehydrated apples.

PubMed

Lavelli, Vera

2009-12-23

Phytochemical contents, color, and inhibition efficacy toward oxidative and glycoxidative reactions were studied in dehydrated apples following storage in the water activity range from 0.1 to 0.7 at 20, 30, and 40 degrees C, which can be considered as room conditions. Hunter colorimetric parameters were analyzed at different temperatures and time intervals, and nonenzymatic browning was modeled according to pseudo-zero-order kinetics. The effect of temperature on the browning rate followed the Arrhenius equation, with an activation energy of 64000 J/mol, which was not affected by the water activity level. The phytochemical contents, inhibition efficacy of protein glycation, and antioxidant properties were then analyzed in the products stored under selected "equivalent" conditions in terms of browning effects, namely, 120 days/20 degrees C, 50 days/30 degrees C, and 22 days/40 degrees C. After storage for 120 days/20 degrees C, the retention percentages of hydroxycinnamic acids, phloridzin, and epicatechin were >86%, but ascorbic acid, catechin, and procyanidins were less stable; concurrently dehydrated apples retained about 80% of the radical scavenging activity and 70% of the ability to inhibit protein glycation. Following storage at higher temperatures the expected browning effect occurred in a shorter time scale; however, the patterns of product degradation were different. A sharp increase in the degradation rates of all antioxidants, relative to browning rate, was observed at temperatures >or=30 degrees C, and this trend was accelerated with concurrent increase in water activity at >0.3 levels. The application of low-temperature/long-time conditions for storage of dehydrated apples corresponded to maximum retention of their efficacy to counteract oxidative and glycoxidative reactions, which have been linked to human chronic diseases.

Chitosan use in chemical conditioning for dewatering municipal-activated sludge.

PubMed

Zemmouri, H; Mameri, N; Lounici, H

2015-01-01

This work aims to evaluate the potential use of chitosan as an eco-friendly flocculant in chemical conditioning of municipal-activated sludge. Chitosan effectiveness was compared with synthetic cationic polyelectrolyte Sedipur CF802 (Sed CF802) and ferric chloride (FeCl₃). In this context, raw sludge samples from Beni-Messous wastewater treatment plant (WWTP) were tested. The classic jar test method was used to condition sludge samples. Capillary suction time (CST), specific resistance to filtration (SRF), cakes dry solid content and filtrate turbidity were analyzed to determine filterability, dewatering capacity of conditioned sludge and the optimum dose of each conditioner. Data exhibit that chitosan, FeCl₃and Sed CF802 improve sludge dewatering. Optimum dosages of chitosan, Sed CF802 and FeCl₃allowing CST values of 6, 5 and 9 s, were found, respectively, between 2-3, 1.5-3 and 6 kg/t ds. Both polymers have shown faster water removal with more permeable sludge. SRF values were 0.634 × 10¹², 0.932 × 10¹² and 2 × 10¹² m/kg for Sed CF802, chitosan and FeCl₃respectively. A reduction of 94.68 and 87.85% of the filtrate turbidity was obtained with optimal dosage of chitosan and Sed CF802, respectively. In contrast, 54.18% of turbidity abatement has been obtained using optimal dosage of FeCl₃.

Dielectric properties of water under extreme conditions and transport of carbonates in the deep Earth.

PubMed

Pan, Ding; Spanu, Leonardo; Harrison, Brandon; Sverjensky, Dimitri A; Galli, Giulia

2013-04-23

Water is a major component of fluids in the Earth's mantle, where its properties are substantially different from those at ambient conditions. At the pressures and temperatures of the mantle, experiments on aqueous fluids are challenging, and several fundamental properties of water are poorly known; e.g., its dielectric constant has not been measured. This lack of knowledge of water dielectric properties greatly limits our ability to model water-rock interactions and, in general, our understanding of aqueous fluids below the Earth's crust. Using ab initio molecular dynamics, we computed the dielectric constant of water under the conditions of the Earth's upper mantle, and we predicted the solubility products of carbonate minerals. We found that MgCO3 (magnesite)--insoluble in water under ambient conditions--becomes at least slightly soluble at the bottom of the upper mantle, suggesting that water may transport significant quantities of oxidized carbon. Our results suggest that aqueous carbonates could leave the subducting lithosphere during dehydration reactions and could be injected into the overlying lithosphere. The Earth's deep carbon could possibly be recycled through aqueous transport on a large scale through subduction zones.

Rheological and fractal characteristics of unconditioned and conditioned water treatment residuals.

PubMed

Dong, Y J; Wang, Y L; Feng, J

2011-07-01

The rheological and fractal characteristics of raw (unconditioned) and conditioned water treatment residuals (WTRs) were investigated in this study. Variations in morphology, size, and image fractal dimensions of the flocs/aggregates in these WTR systems with increasing polymer doses were analyzed. The results showed that when the raw WTRs were conditioned with the polymer CZ8688, the optimum polymer dosage was observed at 24 kg/ton dry sludge. The average diameter of irregularly shaped flocs/aggregates in the WTR suspensions increased from 42.54 μm to several hundred micrometers with increasing polymer doses. Furthermore, the aggregates in the conditioned WTR system displayed boundary/surface and mass fractals. At the optimum polymer dosage, the aggregates formed had a volumetric average diameter of about 820.7 μm, with a one-dimensional fractal dimension of 1.01 and a mass fractal dimension of 2.74 on the basis of the image analysis. Rheological tests indicated that the conditioned WTRs at the optimum polymer dosage showed higher levels of shear-thinning behavior than the raw WTRs. Variations in the limiting viscosity (η(∞)) of conditioned WTRs with sludge content could be described by a linear equation, which were different from the often-observed empirical exponential relationship for most municipal sludge. With increasing temperature, the η(∞) of the raw WTRs decreased more rapidly than that of the raw WTRs. Good fitting results for the relationships between lgη(∞)∼T using the Arrhenius equation indicate that the WTRs had a much higher activation energy for viscosity of about 17.86-26.91 J/mol compared with that of anaerobic granular sludge (2.51 J/mol) (Mu and Yu, 2006). In addition, the Bingham plastic model adequately described the rheological behavior of the conditioned WTRs, whereas the rheology of the raw WTRs fit the Herschel-Bulkley model well at only certain sludge contents. Considering the good power-law relationships between the

Comparative study of carbonic anhydrase activity in waters among different geological eco-environments of Yangtze River basin and its ecological significance.

PubMed

Nzung'a, Sila Onesmus; Pan, Weizhi; Shen, Taiming; Li, Wei; Qin, Xiaoqun; Wang, Chenwei; Zhang, Liankai; Yu, Longjiang

2018-04-01

This study provides the presence of carbonic anhydrase (CA) activity in waters of the Yangtze River basin, China, as well as the correlation of CA activity with HCO 3 - concentration and CO 2 sink flux. Different degrees of CA activity could be detected in almost all of the water samples from different geological eco-environments in all four seasons. The CA activity of water samples from karst areas was significantly higher than from non-karst areas (PP3 - concentration (r=0.672, P2 sink flux (r=0.602, P=0.076) in karst areas. This suggests that CA in waters might have a promoting effect on carbon sinks for atmospheric CO 2 in karst river basins. In conditions of similar geological type, higher CA activity was generally detected in water samples taken from areas that exhibited better eco-environments, implying that the CA activity index of waters could be used as an indicator for monitoring ecological environments and protection of river basins. These findings suggest that the role of CA in waters in the karst carbon sink potential of river basins is worthy of further in-depth studies. Copyright © 2017. Published by Elsevier B.V.

Validation of feasibility and quality of chicken breast meat cooked under various water-cooking conditions.

PubMed

Chumngoen, Wanwisa; Chen, Hsin-Yi; Tan, Fa-Jui

2016-12-01

Under laboratory conditions, the qualities of boneless chicken breasts are commonly determined by placing them in a bag and cooking them in a water bath. The results are often applied as references for comparing the influences of cooking techniques. However, whether a sample cooked under this "laboratory" condition actually represents the meat cooked under the "real-life" condition in which meat is frequently cooked directly in water without packaging remains unclear. Whether the two cooking conditions lead to comparable results in meat quality should be determined. This study evaluated the influence of cooking conditions, including "placed-in-bag and cooked in a water bath (BC)" and "cooked directly in hot water (WC)" conditions, on the quality of chicken meat. The results reveal that BC samples had a longer cooking time. Deboned-and-skinless BC samples had a higher cooking loss and lower protein solubility (P < 0.01). BC samples with bone and skin had a higher lightness in both skin and muscle. No significant differences were observed in attributes, including shear force, collagen solubility, microstructures, redness, yellowness and descriptive sensory characteristics between treatments. Based on the results, considering the quality attributes that might be influenced, is critical when conducting relevant research. © 2016 Japanese Society of Animal Science.

Active layer hydrology in an arctic tundra ecosystem: quantifying water sources and cycling using water stable isotopes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Throckmorton, Heather M.; Newman, Brent D.; Heikoop, Jeffrey M.

Climate change and thawing permafrost in the Arctic will significantly alter landscape hydro-geomorphology and the distribution of soil moisture, which will have cascading effects on climate feedbacks (CO 2 and CH 4) and plant and microbial communities. Fundamental processes critical to predicting active layer hydrology are not well understood. This study applied water stable isotope techniques (δ 2H and δ 18O) to infer sources and mixing of active layer waters in a polygonal tundra landscape in Barrow, Alaska (USA), in August and September of 2012. Results suggested that winter precipitation did not contribute substantially to surface waters or subsurface activemore » layer pore waters measured in August and September. Summer rain was the main source of water to the active layer, with seasonal ice melt contributing to deeper pore waters later in the season. Surface water evaporation was evident in August from a characteristic isotopic fractionation slope (δ 2H vs δ 18O). Freeze-out isotopic fractionation effects in frozen active layer samples and textural permafrost were indistinguishable from evaporation fractionation, emphasizing the importance of considering the most likely processes in water isotope studies, in systems where both evaporation and freeze-out occur in close proximity. The fractionation observed in frozen active layer ice was not observed in liquid active layer pore waters. Such a discrepancy between frozen and liquid active layer samples suggests mixing of meltwater, likely due to slow melting of seasonal ice. In conclusion, this research provides insight into fundamental processes relating to sources and mixing of active layer waters, which should be considered in process-based fine-scale and intermediate-scale hydrologic models.« less

Active layer hydrology in an arctic tundra ecosystem: quantifying water sources and cycling using water stable isotopes

DOE PAGES

Throckmorton, Heather M.; Newman, Brent D.; Heikoop, Jeffrey M.; ...

2016-04-16

Climate change and thawing permafrost in the Arctic will significantly alter landscape hydro-geomorphology and the distribution of soil moisture, which will have cascading effects on climate feedbacks (CO 2 and CH 4) and plant and microbial communities. Fundamental processes critical to predicting active layer hydrology are not well understood. This study applied water stable isotope techniques (δ 2H and δ 18O) to infer sources and mixing of active layer waters in a polygonal tundra landscape in Barrow, Alaska (USA), in August and September of 2012. Results suggested that winter precipitation did not contribute substantially to surface waters or subsurface activemore » layer pore waters measured in August and September. Summer rain was the main source of water to the active layer, with seasonal ice melt contributing to deeper pore waters later in the season. Surface water evaporation was evident in August from a characteristic isotopic fractionation slope (δ 2H vs δ 18O). Freeze-out isotopic fractionation effects in frozen active layer samples and textural permafrost were indistinguishable from evaporation fractionation, emphasizing the importance of considering the most likely processes in water isotope studies, in systems where both evaporation and freeze-out occur in close proximity. The fractionation observed in frozen active layer ice was not observed in liquid active layer pore waters. Such a discrepancy between frozen and liquid active layer samples suggests mixing of meltwater, likely due to slow melting of seasonal ice. In conclusion, this research provides insight into fundamental processes relating to sources and mixing of active layer waters, which should be considered in process-based fine-scale and intermediate-scale hydrologic models.« less

The influence of water and redox conditions on the seismic properties of olivine

NASA Astrophysics Data System (ADS)

Cline, C. J., II; Jackson, I.; Faul, U.; David, E. C.; Berry, A.

2017-12-01

Eight polycrystalline olivine specimens of both synthetic (solution-gelation derived) and natural (San Carlos) origins were fabricated by hot-pressing at 1200°C and 300 MPa. Amongst these specimens, six contained varying concentrations of Ti, allowing control of hydroxyl (or `water') content through the creation of the energetically favored Ti-clinohumite-like defect (doubly protonated Si vacancy associated with a Ti/Mg substitution). Along with a Ti-free Fo90 specimen, these materials have Ti contents ranging between 0 and 802 atom ppm Ti/Si and associated chemically bound `water' contents between 0 and 1150 atom ppm H/Si, along with molecular water concentrations between 0 and 245 atom ppm H/Si. Each hot-pressed specimen was then subsequently wrapped in Pt, Ni or NiFe foil to control oxygen fugacity (fO2), and interrogated under water-undersaturated conditions via forced torsional oscillation. Testing was conducted at seismic periods of 1 - 1000 s and 200 MPa confining pressure during slow staged cooling from 1200 to 25°C. All specimens, regardless of water content or metal sleeving, exhibit high temperature background behavior, involving monotonically increasing levels of dissipation and concomitantly decreasing shear modulus with increasing oscillation period and increasing temperature. Our experimental results demonstrate unambiguously that water content (and water fugacity) has a negligible effect on the measured seismic properties olivine. Rather, a relationship between the prevailing redox conditions set by the metal sleeving and the magnitude of anelastic relaxation was observed. These results suggest that low velocity and high attenuation anomalies in the upper mantle are not due to elevated water contents. Instead, in oxidized and hydrous regions above subducting slabs and perhaps in the oceanic asthenosphere, high attenuation may reflect elevated fO2 conditions.

Provision of water by halite deliquescence for Nostoc commune biofilms under Mars relevant surface conditions

NASA Astrophysics Data System (ADS)

Jänchen, Jochen; Feyh, Nina; Szewzyk, Ulrich; de Vera, Jean-Pierre P.

2016-04-01

Motivated by findings of new mineral related water sources for organisms under extremely dry conditions on Earth we studied in an interdisciplinary approach the water sorption behaviour of halite, soil component and terrestrial Nostoc commune biofilm under Mars relevant environmental conditions. Physicochemical methods served for the determination of water sorption equilibrium data and survival of heterotrophic bacteria in biofilm samples with different water contents was assured by recultivation. Deliquescence of halite provides liquid water at temperatures <273 K and may serve as water source on Mars during the morning stabilized by the CO2 atmosphere for a few hours. The protecting biofilm of N. commune is rather hygroscopic and tends to store water at lower humidity values. Survival tests showed that a large proportion of the Alphaproteobacteria dominated microbiota associated to N. commune is very desiccation tolerant and water uptake from saturated NaCl solutions (either by direct uptake of brine or adsorption of humidity) did not enhance recultivability in long-time desiccated samples. Still, a minor part can grow under highly saline conditions. However, the salinity level, although unfavourable for the host organism, might be for parts of the heterotrophic microbiota no serious hindrance for growing in salty Mars-like environments.

Water Wisdom: 23 Stand-Alone Activities on Water Supply and Water Conservation for High School Students. 2nd Edition.

ERIC Educational Resources Information Center

Massachusetts State Water Resources Authority, Boston.

This water conservation education program for high schools consists of both stand-alone activities and teacher support materials. Lessons are divided into six broad categories: (1) The Water Cycle; (2) Water and Society; (3) Keeping Water Pure; (4) Visualizing Volumes; (5) The Economics of Water Use; and (6) Domestic Water Conservation. The…

Quality-assurance and data-management plan for water-quality activities in the Kansas Water Science Center, 2014

USGS Publications Warehouse

Rasmussen, Teresa J.; Bennett, Trudy J.; Foster, Guy M.; Graham, Jennifer L.; Putnam, James E.

2014-01-01

As the Nation’s largest water, earth, and biological science and civilian mapping information agency, the U.S. Geological Survey is relied on to collect high-quality data, and produce factual and impartial interpretive reports. This quality-assurance and data-management plan provides guidance for water-quality activities conducted by the Kansas Water Science Center. Policies and procedures are documented for activities related to planning, collecting, storing, documenting, tracking, verifying, approving, archiving, and disseminating water-quality data. The policies and procedures described in this plan complement quality-assurance plans for continuous water-quality monitoring, surface-water, and groundwater activities in Kansas.

Genome-wide transcriptome analysis of soybean primary root under varying water-deficit conditions.

PubMed

Song, Li; Prince, Silvas; Valliyodan, Babu; Joshi, Trupti; Maldonado dos Santos, Joao V; Wang, Jiaojiao; Lin, Li; Wan, Jinrong; Wang, Yongqin; Xu, Dong; Nguyen, Henry T

2016-01-15

Soybean is a major crop that provides an important source of protein and oil to humans and animals, but its production can be dramatically decreased by the occurrence of drought stress. Soybeans can survive drought stress if there is a robust and deep root system at the early vegetative growth stage. However, little is known about the genome-wide molecular mechanisms contributing to soybean root system architecture. This study was performed to gain knowledge on transcriptome changes and related molecular mechanisms contributing to soybean root development under water limited conditions. The soybean Williams 82 genotype was subjected to very mild stress (VMS), mild stress (MS) and severe stress (SS) conditions, as well as recovery from the severe stress after re-watering (SR). In total, 6,609 genes in the roots showed differential expression patterns in response to different water-deficit stress levels. Genes involved in hormone (Auxin/Ethylene), carbohydrate, and cell wall-related metabolism (XTH/lipid/flavonoids/lignin) pathways were differentially regulated in the soybean root system. Several transcription factors (TFs) regulating root growth and responses under varying water-deficit conditions were identified and the expression patterns of six TFs were found to be common across the stress levels. Further analysis on the whole plant level led to the finding of tissue-specific or water-deficit levels specific regulation of transcription factors. Analysis of the over-represented motif of different gene groups revealed several new cis-elements associated with different levels of water deficit. The expression patterns of 18 genes were confirmed byquantitative reverse transcription polymerase chain reaction method and demonstrated the accuracy and effectiveness of RNA-Seq. The primary root specific transcriptome in soybean can enable a better understanding of the root response to water deficit conditions. The genes detected in root tissues that were associated with

Sea/Lake Water Air Conditioning at Naval Facilities.

DTIC Science & Technology

1980-05-01

ECONOMICS AT TWO FACILITIES ......... ................... 2 Facilities ........... .......................... 2 Computer Models...of an operational test at Naval Security Group Activity (NSGA) Winter Harbor, Me., and the economics of Navywide application. In FY76 an assessment of... economics of Navywide application of sea/lake water AC indicated that cost and energy savings at the sites of some Naval facilities are possible, depending

Water in the active site of ketosteroid isomerase.

PubMed

Hanoian, Philip; Hammes-Schiffer, Sharon

2011-08-09

Classical molecular dynamics simulations were utilized to investigate the structural and dynamical properties of water in the active site of ketosteroid isomerase (KSI) to provide insight into the role of these water molecules in the enzyme-catalyzed reaction. This reaction is thought to proceed via a dienolate intermediate that is stabilized by hydrogen bonding with residues Tyr16 and Asp103. A comparative study was performed for the wild-type (WT) KSI and the Y16F, Y16S, and Y16F/Y32F/Y57F (FFF) mutants. These systems were studied with three different bound ligands: equilenin, which is an intermediate analog, and the intermediate states of two steroid substrates. Several distinct water occupation sites were identified in the active site of KSI for the WT and mutant systems. Three additional sites were identified in the Y16S mutant that were not occupied in WT KSI or the other mutants studied. The number of water molecules directly hydrogen bonded to the ligand oxygen was approximately two in the Y16S mutant and one in the Y16F and FFF mutants, with intermittent hydrogen bonding of one water molecule in WT KSI. The molecular dynamics trajectories of the Y16F and FFF mutants reproduced the small conformational changes of residue 16 observed in the crystal structures of these two mutants. Quantum mechanical/molecular mechanical calculations of (1)H NMR chemical shifts of the protons in the active site hydrogen-bonding network suggest that the presence of water in the active site does not prevent the formation of short hydrogen bonds with far-downfield chemical shifts. The molecular dynamics simulations indicate that the active site water molecules exchange much more frequently for WT KSI and the FFF mutant than for the Y16F and Y16S mutants. This difference is most likely due to the hydrogen-bonding interaction between Tyr57 and an active site water molecule that is persistent in the Y16F and Y16S mutants but absent in the FFF mutant and significantly less probable

Statistical analysis of short-term water stress conditions at Riggs Creek OzFlux tower site

NASA Astrophysics Data System (ADS)

Azmi, Mohammad; Rüdiger, Christoph; Walker, Jeffrey P.

2017-10-01

A large range of indices and proxies are available to describe the water stress conditions of an area subject to different applications, which have varying capabilities and limitations depending on the prevailing local climatic conditions and land cover. The present study uses a range of spatio-temporally high-resolution (daily and within daily) data sources to evaluate a number of drought indices (DIs) for the Riggs Creek OzFlux tower site in southeastern Australia. Therefore, the main aim of this study is to evaluate the statistical characteristics of individual DIs subject to short-term water stress conditions. In order to derive a more general and therefore representative DI, a new criterion is required to specify the statistical similarity between each pair of indices to allow determining the dominant drought types along with their representative DIs. The results show that the monitoring of water stress at this case study area can be achieved by evaluating the individual behaviour of three clusters of (i) vegetation conditions, (ii) water availability and (iii) water consumptions. This indicates that it is not necessary to assess all individual DIs one by one to derive a comprehensive and informative data set about the water stress of an area; instead, this can be achieved by analysing one of the DIs from each cluster or deriving a new combinatory index for each cluster, based on established combination methods.

Hypotheses of Spatial Stock Structure in Orange Roughy Hoplostethus atlanticus Inferred from Diet, Feeding, Condition, and Reproductive Activity

PubMed Central

Dunn, Matthew R.; Forman, Jeffrey S.

2011-01-01

We evaluate hypotheses for meso-scale spatial structure in an orange roughy (Hoplostethus atlanticus) stock using samples collected during research trawl surveys off the east coast of New Zealand. Distance-based linear models and generalised additive models were used to identify the most significant biological, environmental, and temporal predictors of variability in diet, proportion of stomachs containing prey, standardised weight of prey, fish somatic weight, fish total weight, and reproductive activity. The diet was similar to that observed elsewhere, and varied with ontogeny, depth, and surface water temperature. Smaller sized and female orange roughy in warmer bottom water were most likely to contain food. Fish condition and reproductive activity were highest at distances more than 20 km from the summit of the hills. Trawl survey catches indicated greater orange roughy densities in hill strata, suggesting hill habitat was favoured. However, analyses of feeding, condition, and reproductive activity indicated hill fish were not superior, despite fish densities on hills being reduced by fishing which, in principle, should have reduced intra-specific competition for food and other resources. Hypotheses for this result include: (1) fish in relatively poor condition visit hills to feed and regain condition and then leave, or (2) commercial fishing has disturbed feeding aggregations and/or caused habitat damage, making fished hills less productive. Mature orange roughy were observed on both flat and hill habitat during periods outside of spawning, and if this spatial structure was persistent then a proportion of the total spawning stock biomass would remain unavailable to fisheries targeting hills. Orange roughy stock assessments informed only by data from hills may well be misleading. PMID:22069464

Rubisco activity in Mediterranean species is regulated by the chloroplastic CO2 concentration under water stress

PubMed Central

Galmés, Jeroni; Ribas-Carbó, Miquel; Medrano, Hipólito; Flexas, Jaume

2011-01-01

Water stress decreases the availability of the gaseous substrate for ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) by decreasing leaf conductance to CO2. In spite of limiting photosynthetic carbon assimilation, especially in those environments where drought is the predominant factor affecting plant growth and yield, the effects of water deprivation on the mechanisms that control Rubisco activity are unclear. In the present study, 11 Mediterranean species, representing different growth forms, were subject to increasing levels of drought stress, the most severe one followed by rewatering. The results confirmed species-specific patterns in the decrease in the initial activity and activation state of Rubisco as drought stress and leaf dehydration intensified. Nevertheless, all species followed roughly the same trend when Rubisco activity was related to stomatal conductance (gs) and chloroplastic CO2 concentration (Cc), suggesting that deactivation of Rubisco sites could be induced by low Cc, as a result of water stress. The threshold level of Cc that triggered Rubisco deactivation was dependent on leaf characteristics and was related to the maximum attained for each species under non-stressing conditions. Those species adapted to low Cc were more capable of maintaining active Rubisco as drought stress intensified. PMID:21115663

Biological filters and their use in potable water filtration systems in spaceflight conditions

NASA Astrophysics Data System (ADS)

Thornhill, Starla G.; Kumar, Manish

2018-05-01

Providing drinking water to space missions such as the International Space Station (ISS) is a costly requirement for human habitation. To limit the costs of water transport, wastewater is collected and purified using a variety of physical and chemical means. To date, sand-based biofilters have been designed to function against gravity, and biofilms have been shown to form in microgravity conditions. Development of a universal silver-recycling biological filter system that is able to function in both microgravity and full gravity conditions would reduce the costs incurred in removing organic contaminants from wastewater by limiting the energy and chemical inputs required. This paper aims to propose the use of a sand-substrate biofilter to replace chemical means of water purification on manned spaceflights.

Model-Assisted Estimation of the Genetic Variability in Physiological Parameters Related to Tomato Fruit Growth under Contrasted Water Conditions

PubMed Central

Constantinescu, Dario; Memmah, Mohamed-Mahmoud; Vercambre, Gilles; Génard, Michel; Baldazzi, Valentina; Causse, Mathilde; Albert, Elise; Brunel, Béatrice; Valsesia, Pierre; Bertin, Nadia

2016-01-01

Drought stress is a major abiotic stress threatening plant and crop productivity. In case of fleshy fruits, understanding mechanisms governing water and carbon accumulations and identifying genes, QTLs and phenotypes, that will enable trade-offs between fruit growth and quality under Water Deficit (WD) condition is a crucial challenge for breeders and growers. In the present work, 117 recombinant inbred lines of a population of Solanum lycopersicum were phenotyped under control and WD conditions. Plant water status, fruit growth and composition were measured and data were used to calibrate a process-based model describing water and carbon fluxes in a growing fruit as a function of plant and environment. Eight genotype-dependent model parameters were estimated using a multiobjective evolutionary algorithm in order to minimize the prediction errors of fruit dry and fresh mass throughout fruit development. WD increased the fruit dry matter content (up to 85%) and decreased its fresh weight (up to 60%), big fruit size genotypes being the most sensitive. The mean normalized root mean squared errors of the predictions ranged between 16–18% in the population. Variability in model genotypic parameters allowed us to explore diverse genetic strategies in response to WD. An interesting group of genotypes could be discriminated in which (i) the low loss of fresh mass under WD was associated with high active uptake of sugars and low value of the maximum cell wall extensibility, and (ii) the high dry matter content in control treatment (C) was associated with a slow decrease of mass flow. Using 501 SNP markers genotyped across the genome, a QTL analysis of model parameters allowed to detect three main QTLs related to xylem and phloem conductivities, on chromosomes 2, 4, and 8. The model was then applied to design ideotypes with high dry matter content in C condition and low fresh mass loss in WD condition. The ideotypes outperformed the RILs especially for large and medium

Ground-water conditions and studies in Georgia, 2001

USGS Publications Warehouse

Leeth, David C.; Clarke, John S.; Craigg, Steven D.; Wipperfurth, Caryl J.

2003-01-01

The U.S. Geological Survey (USGS) collects ground-water data and conducts studies to monitor hydrologic conditions, to better define ground-water resources, and address problems related to water supply and water quality. Data collected as part of ground-water studies include geologic, geophysical, hydraulic property, water level, and water quality. A ground-water-level network has been established throughout most of the State of Georgia, and ground-water-quality networks have been established in the cities of Albany, Savannah, and Brunswick and in Camden County, Georgia. Ground-water levels are monitored continuously in a network of wells completed in major aquifers of the State. This network includes 17 wells in the surficial aquifer, 12 wells in the upper and lower Brunswick aquifers, 73 wells in the Upper Floridan aquifer, 10 wells in the Lower Floridan aquifer and underlying units, 12 wells in the Claiborne aquifer, 1 well in the Gordon aquifer, 11 wells in the Clayton aquifer, 11 wells in the Cretaceous aquifer system, 2 wells in Paleozoic-rock aquifers, and 7 wells in crystalline-rock aquifers. In this report, data from these 156 wells were evaluated to determine whether mean-annual ground-water levels were within, below, or above the normal range during 2001, based on summary statistics for the period of record. Information from these summaries indicates that water levels during 2001 were below normal in almost all aquifers monitored, largely reflecting climatic effects from drought and pumping. In addition, water-level hydrographs for selected wells indicate that water levels have declined during the past 5 years (since 1997) in almost all aquifers monitored, with water levels in some wells falling below historical lows. In addition to continuous water-level data, periodic measurements taken in 52 wells in the Camden County-Charlton County area, and 65 wells in the city of Albany-Dougherty County area were used to construct potentiometric-surface maps for

Reconstruction of surface water conditions in the central region of the Okhotsk Sea during the last 180 kyrs

NASA Astrophysics Data System (ADS)

Khim, Boo-Keun; Sakamoto, Tatsuhiko; Harada, Naomi

2012-02-01

Core GC9A, a 6.7 m long gravity core collected from the central region of the Okhotsk Sea during Cruise YK0712 on R/V Yokosuka (JAMSTEC), was used to reconstruct the changes in surface water conditions by measuring biogenic components (biogenic opal, CaCO3, total organic carbon and δ15N of sediment organic matter) of sediment samples. The age of Core GC9A was determined indirectly by graphic correlation comparing the b* (psychometric yellow-blue chromaticness) values with those of well-dated Core MD01-2415, with complement to the tephra layer (K3; 50 ka). The bottom age of Core GC9A was estimated to be about 180 kyr; therefore it provides the history of surface water conditions from MIS 1 to MIS 6. The biogenic opal, CaCO3, and TOC contents were high during the interglacial periods as expected, indicating enhanced surface water production under warm climatic conditions. This condition resulted from sufficient nutrient supply to the surface waters by active vertical mixing, which was validated by low δ15N values of the sediment organic matter. In contrast, surface water productivity was depressed during the colder glacial periods, probably due to the expanded sea-ice distribution and limited nutrient supply. However, the glacial sediments had moderately high δ15N values, indicating enhanced nitrate utilization resulting from the limited nutrient supply caused by strong stratification of the surface water. High δ15N values were also observed during the deglaciation, which was attributed to the increased nitrate utilization during enhanced surface water productivity. However, the low δ15N values during the glacial and deglacial periods may be attributed to the increased supply of terrestrial organic matter. Diatom production was primarily responsible for surface water paleoproductivity during the interglacial periods rather than coccolithophores. However, the succession of glacial to early deglacial coccolithophore production and late deglacial to interglacial

Modeling the Impact of Soil Conditions on Global Water Balance

NASA Astrophysics Data System (ADS)

Wang, P. L.; Feddema, J. J.

2016-12-01

The amount of water the soil can hold for plant use, defined as soil water-holding capacity (WHC), has a large influence on the water cycle and climatic variables. Although soil properties vary widely worldwide, many climate modeling applications assume WHC to be spatially invariant. This study explores how a more realistic soil WHC estimate affects the global water balance relative to commonly assumed soil properties. We use a modified Thornthwaite water balance model combined with a newly developed soil WHC and soil thickness data at a 30 arc second resolution. The soil WHC data was obtained by integrating WHCs to a depth of 2 m and modified by the soil thickness data on a grid-by-grid basis, and then resampling to the 0.5 degree climatology data. We observed that down scaling soils data before modifying soil depths greatly increases global soil WHCs. This new dataset is compared to WHC information with a fixed 2-m soil depth, and a constant 150-mm soil WHC. Results indicate higher soil WHC results in increased soil moisture, decreased moisture surplus and deficits, and increased actual evapotranspiration (AE), and vice-versa. However, due to high variability in soil characteristics across climate gradients, this generalization does not hold true for regionally averaged outcomes. Compared to using a constant 150-mm WHC, more realistic soil WHC increases global averaged AE 1%, and decreases deficit 2% and surplus 3%. Most change is observed in areas with pronounced wet and dry seasons; using a constant 2-m soil depth doubles the differences. Regionally, Europe was most affected: AE increases 4%, and the deficit and surplus decrease 20% and 12%. Australia shows that regionally averaged results are not equivocal for moisture surplus and deficit; deficit decreases 0.4%, while surplus decreases 9%. This research highlights the importance of soil condition for climate modeling and how a better representation of soil moisture conditions affects global water balance

Effect of boundary conditions on measured water retention behavior within soils

NASA Astrophysics Data System (ADS)

Galindo-torres, S.; Scheuermann, A.; Pedroso, D.; Li, L.

2013-12-01

The Soil Water Characteristic Curve (SWCC) is a practical representation of the behavior of soil water by relating the suction (difference between the air and water pressures to the moisture content (water saturation). The SWCC is characterized by a hysteresis loop, which is thought to be unique in that any drainage-imbibition cycle lies within a main hysteresis loop limited by two different curves for drainage and imbibition. This 'uniqueness' is the main argument for considering the SWCC as a material-intrinsic feature that characterizes the pore structure and its interaction with fluids. Models have been developed with the SWCC as input data to describe the evolution of the water saturation and the suction within soils. One example of these models is the widely used Richard's equation [1]. In this work we present a series of numerical simulations to evaluate the 'unique' nature of the SWCC. The simulations involves the use of the Lattice Boltzmann Method (LBM) [2] within a regular soil, modelling the flow behavior of two immiscible fluids: wetting and non-wetting. The soil is packed within a cubic domain to resemble the experimental setups that are commonly used for measuring the SWCC[3]. The boundary conditions ensure that the non-wetting phase enters through one cubic face and the wetting phase enters trough the opposite phase, with no flow boundary conditions in the remaining 4 cubic faces. The SWCC known features are inspected including the presence of the common limit curves for different cycles involving varying limits for the suction. For this stage of simulations, the SWCC is indeed unique. Later, different boundary conditions are applied with the two fluids each injected from 3 opposing faces into the porous medium. The effect of this boundary condition change is a net flow direction, which is different from that in the previous case. A striking result is observed when both SWCC are compared and found to be noticeable different. Further analysis is

Azospirillum and arbuscular mycorrhizal colonization enhance rice growth and physiological traits under well-watered and drought conditions.

PubMed

Ruíz-Sánchez, Michel; Armada, Elisabet; Muñoz, Yaumara; García de Salamone, Inés E; Aroca, Ricardo; Ruíz-Lozano, Juan Manuel; Azcón, Rosario

2011-07-01

The response of rice plants to inoculation with an arbuscular mycorrhizal (AM) fungus, Azospirillum brasilense, or combination of both microorganisms, was assayed under well-watered or drought stress conditions. Water deficit treatment was imposed by reducing the amount of water added, but AM plants, with a significantly higher biomass, received the same amount of water as non-AM plants, with a poor biomass. Thus, the water stress treatment was more severe for AM plants than for non-AM plants. The results showed that AM colonization significantly enhanced rice growth under both water conditions, although the greatest rice development was reached in plants dually inoculated under well-watered conditions. Water level did not affect the efficiency of photosystem II, but both AM and A. brasilense inoculations increased this value. AM colonization increased stomatal conductance, particularly when associated with A. brasilense, which enhanced this parameter by 80% under drought conditions and by 35% under well-watered conditions as compared to single AM plants. Exposure of AM rice to drought stress decreased the high levels of glutathione that AM plants exhibited under well-watered conditions, while drought had no effect on the ascorbate content. The decrease of glutathione content in AM plants under drought stress conditions led to enhance lipid peroxidation. On the other hand, inoculation with the AM fungus itself increased ascorbate and proline as protective compounds to cope with the harmful effects of water limitation. Inoculation with A. brasilense also enhanced ascorbate accumulation, reaching a similar level as in AM plants. These results showed that, in spite of the fact that drought stress imposed by AM treatments was considerably more severe than non-AM treatments, rice plants benefited not only from the AM symbiosis but also from A. brasilense root colonization, regardless of the watering level. However, the beneficial effects of A. brasilense on most of the

Hypothetical Modeling of Redox Conditions Within a Complex Ground-Water Flow Field in a Glacial Setting

USGS Publications Warehouse

Feinstein, Daniel T.; Thomas, Mary Ann

2009-01-01

This report describes a modeling approach for studying how redox conditions evolve under the influence of a complex ground-water flow field. The distribution of redox conditions within a flow system is of interest because of the intrinsic susceptibility of an aquifer to redox-sensitive, naturally occurring contaminants - such as arsenic - as well as anthropogenic contaminants - such as chlorinated solvents. The MODFLOW-MT3D-RT3D suite of code was applied to a glacial valley-fill aquifer to demonstrate a method for testing the interaction of flow patterns, sources of reactive organic carbon, and availability of electron acceptors in controlling redox conditions. Modeling results show how three hypothetical distributions of organic carbon influence the development of redox conditions in a water-supply aquifer. The distribution of strongly reduced water depends on the balance between the rate of redox reactions and the capability of different parts of the flow system to transmit oxygenated water. The method can take account of changes in the flow system induced by pumping that result in a new distribution of reduced water.

Selenium Supplementation Affects Physiological and Biochemical Processes to Improve Fodder Yield and Quality of Maize (Zea mays L.) under Water Deficit Conditions

PubMed Central

Nawaz, Fahim; Naeem, Muhammad; Ashraf, Muhammad Y.; Tahir, Muhammad N.; Zulfiqar, Bilal; Salahuddin, Muhammad; Shabbir, Rana N.; Aslam, Muhammad

2016-01-01

Climate change is one of the most complex challenges that pose serious threats to livelihoods of poor people who rely heavily on agriculture and livestock particularly in climate-sensitive developing countries of the world. The negative effects of water scarcity, due to climate change, are not limited to productivity food crops but have far-reaching consequences on livestock feed production systems. Selenium (Se) is considered essential for animal health and has also been reported to counteract various abiotic stresses in plants, however, understanding of Se regulated mechanisms for improving nutritional status of fodder crops remains elusive. We report the effects of exogenous selenium supply on physiological and biochemical processes that may influence green fodder yield and quality of maize (Zea mays L.) under drought stress conditions. The plants were grown in lysimeter tanks under natural conditions and were subjected to normal (100% field capacity) and water stress (60% field capacity) conditions. Foliar spray of Se was carried out before the start of tasseling stage (65 days after sowing) and was repeated after 1 week, whereas, water spray was used as a control. Drought stress markedly reduced the water status, pigments and green fodder yield and resulted in low forage quality in water stressed maize plants. Nevertheless, exogenous Se application at 40 mg L-1 resulted in less negative leaf water potential (41%) and enhanced relative water contents (30%), total chlorophyll (53%), carotenoid contents (60%), accumulation of total free amino acids (40%) and activities of superoxide dismutase (53%), catalase (30%), peroxidase (27%), and ascorbate peroxidase (27%) with respect to control under water deficit conditions. Consequently, Se regulated processes improved fodder yield (15%) and increased crude protein (47%), fiber (10%), nitrogen free extract (10%) and Se content (36%) but did not affect crude ash content in water stressed maize plants. We propose that Se

Contribution of water hyacinth (Eichhornia crassipes (Mart.) Solms) grown under different nutrient conditions to Fe-removal mechanisms in constructed wetlands.

PubMed

Jayaweera, Mahesh W; Kasturiarachchi, Jagath C; Kularatne, Ranil K A; Wijeyekoon, Suren L J

2008-05-01

Severe contamination of water resources including groundwater with iron (Fe) due to various anthropogenic activities has been a major environmental problem in industrial areas of Sri Lanka. Hence, the use of the obnoxious weed, water hyacinth (Eichhornia crassipes (Mart.) Solms) in constructed wetlands (floating aquatic macrophyte-based plant treatment systems) to phytoremediate Fe-rich wastewaters seems to be an appealing option. Although several studies have documented that hyacinths are good metal-accumulating plants none of these studies have documented the ability of this plant grown under different nutrient conditions to remove heavy metals from wastewaters. This paper, therefore, reports the phytoremediation efficiencies of water hyacinth grown under different nutrient conditions for Fe-rich wastewaters in batch-type constructed wetlands. This study was conducted for 15 weeks after 1-week acclimatization by culturing young water hyacinth plants (average height of 20+/-2cm) in 590L capacity fiberglass tanks under different nutrient concentrations of 1-fold [28 and 7.7mg/L of total nitrogen (TN) and total phosphorous (TP), respectively], 2-fold, 1/2-fold, 1/4-fold and 1/8-fold with synthetic wastewaters containing 9.27Femg/L. Another set-up of hyacinths containing only Fe as a heavy metal but without any nutrients (i.e., 0-fold) was also studied. A mass balance was carried out to investigate the phytoremediation efficiencies and to determine the different mechanisms governing Fe removal from the wastewaters. Fe removal was largely due to phytoremediation mainly through the process of rhizofiltration and chemical precipitation of Fe2O3 and FeOH3 followed by flocculation and sedimentation. However, chemical precipitation was more significant especially during the first 3 weeks of the study. Plants grown in the 0-fold set-up showed the highest phytoremediation efficiency of 47% during optimum growth at the 6th week with a highest accumulation of 6707Femg/kg dry

Superheated water pretreatment combined with CO2 activation/regeneration of the exhausted activated carbon used in the treatment of industrial wastewater.

PubMed

Xiao, Jin; Yu, Bailie; Zhong, Qifan; Yuan, Jie; Yao, Zhen; Zhang, Liuyun

2017-10-01

This paper examines a novel method of regenerating saturated activated carbon after adsorption of complex phenolic, polycyclic aromatic hydrocarbons with low energy consumption by using superheated water pretreatment combined with CO 2 activation. The effects of the temperature of the superheated water, liquid-solid ratio, soaking time, activation temperature, activation time, and CO 2 flow rate of regeneration and adsorption of coal-powdered activated carbon (CPAC) were studied. The results show that the adsorption capacity of iodine values on CPAC recovers to 102.25% of the fresh activated carbon, and the recovery rate is 79.8% under optimal experimental conditions. The adsorption model and adsorption kinetics of methylene blue on regenerated activated carbon (RAC) showed that the adsorption process was in accordance with the Langmuir model and the pseudo-second-order kinetics model. Furthermore, the internal diffusion process was the main controlling step. The surface properties, Brunauer-Emmett-Teller (BET) surface area, and pore size distribution were characterized by Fourier transform infrared spectroscopy (FT-IR) and BET, which show that the RAC possesses more oxygen-containing functional groups with a specific surface area of 763.39 m 2 g -1 and a total pore volume of 0.3039 cm 3 g -1 . Micropores account for 79.8% and mesopores account for 20.2%.

Active Avoidance: Neural Mechanisms and Attenuation of Pavlovian Conditioned Responding.

PubMed

Boeke, Emily A; Moscarello, Justin M; LeDoux, Joseph E; Phelps, Elizabeth A; Hartley, Catherine A

2017-05-03

Patients with anxiety disorders often experience a relapse in symptoms after exposure therapy. Similarly, threat responses acquired during Pavlovian threat conditioning often return after extinction learning. Accordingly, there is a need for alternative methods to persistently reduce threat responding. Studies in rodents have suggested that exercising behavioral control over an aversive stimulus can persistently diminish threat responses, and that these effects are mediated by the amygdala, ventromedial prefrontal cortex, and striatum. In this fMRI study, we attempted to translate these findings to humans. Subjects first underwent threat conditioning. We then contrasted two forms of safety learning: active avoidance, in which participants could prevent the shock through an action, and yoked extinction, with shock presentation matched to the active condition, but without instrumental control. The following day, we assessed subjects' threat responses (measured by skin conductance) to the conditioned stimuli without shock. Subjects next underwent threat conditioning with novel stimuli. Yoked extinction subjects showed an increase in conditioned response to stimuli from the previous day, but the active avoidance group did not. Additionally, active avoidance subjects showed reduced conditioned responding during novel threat conditioning, but the extinction group did not. We observed between-group differences in striatal BOLD responses to shock omission in Avoidance/Extinction. These findings suggest a differential role for the striatum in human active avoidance versus extinction learning, and indicate that active avoidance may be more effective than extinction in persistently diminishing threat responses. SIGNIFICANCE STATEMENT Extinguished threat responses often reemerge with time, highlighting the importance of identifying more enduring means of attenuation. We compared the effects of active avoidance learning and yoked extinction on threat responses in humans and

Active Avoidance: Neural Mechanisms and Attenuation of Pavlovian Conditioned Responding

PubMed Central

Boeke, Emily A.; Moscarello, Justin M.; Phelps, Elizabeth A.

2017-01-01

Patients with anxiety disorders often experience a relapse in symptoms after exposure therapy. Similarly, threat responses acquired during Pavlovian threat conditioning often return after extinction learning. Accordingly, there is a need for alternative methods to persistently reduce threat responding. Studies in rodents have suggested that exercising behavioral control over an aversive stimulus can persistently diminish threat responses, and that these effects are mediated by the amygdala, ventromedial prefrontal cortex, and striatum. In this fMRI study, we attempted to translate these findings to humans. Subjects first underwent threat conditioning. We then contrasted two forms of safety learning: active avoidance, in which participants could prevent the shock through an action, and yoked extinction, with shock presentation matched to the active condition, but without instrumental control. The following day, we assessed subjects' threat responses (measured by skin conductance) to the conditioned stimuli without shock. Subjects next underwent threat conditioning with novel stimuli. Yoked extinction subjects showed an increase in conditioned response to stimuli from the previous day, but the active avoidance group did not. Additionally, active avoidance subjects showed reduced conditioned responding during novel threat conditioning, but the extinction group did not. We observed between-group differences in striatal BOLD responses to shock omission in Avoidance/Extinction. These findings suggest a differential role for the striatum in human active avoidance versus extinction learning, and indicate that active avoidance may be more effective than extinction in persistently diminishing threat responses. SIGNIFICANCE STATEMENT Extinguished threat responses often reemerge with time, highlighting the importance of identifying more enduring means of attenuation. We compared the effects of active avoidance learning and yoked extinction on threat responses in humans and

[Water contacts in dracunculiasis-infected patients in Mali: transmission risk activities].

PubMed

Etard, J F; Kodio, B; Traoré, S; Audibert, M

2002-11-01

The aim of this study lies in the identification of human activities responsible for the transmission of the Guinea worm in an endemic village in Diema Region in Mali. Human water contacts observations started after a census followed by the implementation of a bi-monthly notification system, carried out from May to November 1993. Water contacts were noticed and observed from the mid-July to the end of November of the same year. The first case of dracunculiasis observed was randomly drawn out of a list of the families with obvious cases. The patent case activities involving either surface water, traditional wells or bore-hole water were recorded for 10 consecutive days. During this observation period, contacts made by other patients with the same water sources were also recorded. After 14 days, the case list was updated and a new case selected out of families previously selected. This cycle was repeated until the end of the study period. A "contact at risk for transmission" was defined by a close correspondence between the location of the worm's emergence and the surface of the skin exposed to water, within two weeks following emergence. Contacts were described according to water sources, activities in relation to water, date, gender and age. Observations were made on 103 patients who had 2506 activities in relation with a water body: 1132 of these activities implied a skin contact with the water. Only 133 (9%) of these water contacts were at risk for transmission, 75% took place during the months of August and September, 80% were related to surface waters and 20% to traditional wells. Woman household activities and boys games were the major activities at risk, in contrast to economic activities (watering cattle). The low proportion of "at risk activities" evaluated in this study suggests that a small number of water contacts is sufficient to maintain the transmission. The case implications of the current eradication strategy might not be sufficient alone to break

Ground water stratification and delivery of nitrate to an incised stream under varying flow conditions.

PubMed

Böhlke, J K; O'Connell, Michael E; Prestegaard, Karen L

2007-01-01

Ground water processes affecting seasonal variations of surface water nitrate concentrations were investigated in an incised first-order stream in an agricultural watershed with a riparian forest in the coastal plain of Maryland. Aquifer characteristics including sediment stratigraphy, geochemistry, and hydraulic properties were examined in combination with chemical and isotopic analyses of ground water, macropore discharge, and stream water. The ground water flow system exhibits vertical stratification of hydraulic properties and redox conditions, with sub-horizontal boundaries that extend beneath the field and adjacent riparian forest. Below the minimum water table position, ground water age gradients indicate low recharge rates (2-5 cm yr(-1)) and long residence times (years to decades), whereas the transient ground water wedge between the maximum and minimum water table positions has a relatively short residence time (months to years), partly because of an upward increase in hydraulic conductivity. Oxygen reduction and denitrification in recharging ground waters are coupled with pyrite oxidation near the minimum water table elevation in a mottled weathering zone in Tertiary marine glauconitic sediments. The incised stream had high nitrate concentrations during high flow conditions when much of the ground water was transmitted rapidly across the riparian zone in a shallow oxic aquifer wedge with abundant outflow macropores, and low nitrate concentrations during low flow conditions when the oxic wedge was smaller and stream discharge was dominated by upwelling from the deeper denitrified parts of the aquifer. Results from this and similar studies illustrate the importance of near-stream geomorphology and subsurface geology as controls of riparian zone function and delivery of nitrate to streams in agricultural watersheds.

Ground water stratification and delivery of nitrate to an incised stream under varying flow conditions

USGS Publications Warehouse

Böhlke, J.K.; O'Connell, M. E.; Prestegaard, K.L.

2007-01-01

Ground water processes affecting seasonal variations of surface water nitrate concentrations were investigated in an incised first-order stream in an agricultural watershed with a riparian forest in the coastal plain of Maryland. Aquifer characteristics including sediment stratigraphy, geochemistry, and hydraulic properties were examined in combination with chemical and isotopic analyses of ground water, macropore discharge, and stream water. The ground water flow system exhibits vertical stratification of hydraulic properties and redox conditions, with sub-horizontal boundaries that extend beneath the field and adjacent riparian forest. Below the minimum water table position, ground water age gradients indicate low recharge rates (2-5 cm yr-1) and long residence times (years to decades), whereas the transient ground water wedge between the maximum and minimum water table positions has a relatively short residence time (months to years), partly because of an upward increase in hydraulic conductivity. Oxygen reduction and denitrification in recharging ground waters are coupled with pyrite oxidation near the minimum water table elevation in a mottled weathering zone in Tertiary marine glauconitic sediments. The incised stream had high nitrate concentrations during high flow conditions when much of the ground water was transmitted rapidly across the riparian zone in a shallow oxic aquifer wedge with abundant outflow macropores, and low nitrate concentrations during low flow conditions when the oxic wedge was smaller and stream discharge was dominated by upwelling from the deeper denitrified parts of the aquifer. Results from this and similar studies illustrate the importance of near-stream geomorphology and subsurface geology as controls of riparian zone function and delivery of nitrate to streams in agricultural watersheds. ?? ASA, CSSA, SSSA.

Acoustic activation of water-in-oil microemulsions for controlled salt dissolution.

PubMed

Baxamusa, Salmaan; Ehrmann, Paul; Ong, Jemi

2018-06-18

The dynamic nature of the oil-water interface allows for sequestration of material within the dispersed domains of a microemulsion. Microstructural changes should therefore change the dissolution rate of a solid surface in a microemulsion. We hypothesize that microstructural changes due to formulation and cavitation in an acoustic field will enable control over solid dissolution rates. Water-in-oil microemulsions were formulated using cyclohexane, water, Triton X-100, and hexanol. The microstructure and solvation properties of Winsor Type IV formulations were characterized. Dissolution rates of KH 2 PO 4 (KDP), were measured. A kinetic analysis isolated the effect of the microstructure, and rate enhancements due to cavitation effects on the microstructure were characterized by measuring dissolution rates in an ultrasonic field. Dispersed aqueous domains of 2-6 nm radius dissolve a solid block of KDP at 0-10 nm/min. Dissolution rate is governed not by the domain-surface collision frequency but rather by a dissolution probability per domain-surface encounter. Higher probabilities are correlated with larger domains. Rapid and reversible dissolution rate increases of up to 270× were observed under ultrasonic conditions, with <20% of the increase due to bulk heating effects. The rest is attributed to cavitation-induced changes to the domain microstructure, providing a simple method for remotely activating and de-activating dissolution. Copyright © 2018 Elsevier Inc. All rights reserved.

Hammerhead ribozyme activity and oligonucleotide duplex stability in mixed solutions of water and organic compounds

PubMed Central

Nakano, Shu-ichi; Kitagawa, Yuichi; Miyoshi, Daisuke; Sugimoto, Naoki

2014-01-01

Nucleic acids are useful for biomedical targeting and sensing applications in which the molecular environment is different from that of a dilute aqueous solution. In this study, the influence of various types of mixed solutions of water and water-soluble organic compounds on RNA was investigated by measuring the catalytic activity of the hammerhead ribozyme and the thermodynamic stability of an oligonucleotide duplex. The compounds with a net neutral charge, such as poly(ethylene glycol), small primary alcohols, amide compounds, and aprotic solvent molecules, added at high concentrations changed the ribozyme-catalyzed RNA cleavage rate, with the magnitude of the effect dependent on the NaCl concentration. These compounds also changed the thermodynamic stability of RNA base pairs of an oligonucleotide duplex and its dependence on the NaCl concentration. Specific interactions with RNA molecules and reduced water activity could account for the inhibiting effects on the ribozyme catalysis and destabilizing effects on the duplex stability. The salt concentration dependence data correlated with the dielectric constant, but not with water activity, viscosity, and the size of organic compounds. This observation suggests the significance of the dielectric constant effects on the RNA reactions under molecular crowding conditions created by organic compounds. PMID:25161873

Simulation and analysis of soil-water conditions in the Great Plains and adjacent areas, central United States, 1951-80

USGS Publications Warehouse

Dugan, Jack T.; Zelt, Ronald B.

2000-01-01

Ground-water recharge and consumptive-irrigation requirements in the Great Plains and adjacent areas largely depend upon an environment extrinsic to the ground-water system. This extrinsic environment, which includes climate, soils, and vegetation, determines the water demands of evapotranspiration, the availability of soil water to meet these demands, and the quantity of soil water remaining for potential ground-water recharge after these demands are met. The geographic extent of the Great Plains contributes to large regional differences among all elements composing the extrinsic environment, particularly the climatic factors. A soil-water simulation program, SWASP, which synthesizes selected climatic, soil, and vegetation factors, was used to simulate the regional soil-water conditions during 1951-80. The output from SWASP consists of several soil-water characteristics, including surface runoff, infiltration, consumptive water requirements, actual evapotranspiration, potential recharge or deep percolation under various conditions, consumptive irrigation requirements, and net fluxes from the ground-water system under irrigated conditions. Simulation results indicate that regional patterns of potential recharge, consumptive irrigation requirements, and net fluxes from the ground-water system under irrigated conditions are largely determined by evapotranspiration and precipitation. The local effects of soils and vegetation on potential recharge cause potential recharge to vary by more than 50 percent in some areas having similar climatic conditions.

Temporal changes in cortical activation during conditioned pain modulation (CPM), a LORETA study.

PubMed

Moont, Ruth; Crispel, Yonatan; Lev, Rina; Pud, Dorit; Yarnitsky, David

2011-07-01

For most healthy subjects, both subjective pain ratings and pain-evoked potentials are attenuated under conditioned pain modulation (CPM; formerly termed diffuse noxious inhibitory controls, or DNIC). Although essentially spinal-bulbar, this inhibition is under cortical control. This is the first study to observe temporal as well as spatial changes in cortical activations under CPM. Specifically, we aimed to investigate the interplay of areas involved in the perception and processing of pain and those involved in controlling descending inhibition. We examined brief consecutive poststimulus time windows of 50 ms using a method of source-localization from pain evoked potentials, sLORETA. This enabled determination of dynamic changes in localized cortical generators evoked by phasic noxious heat stimuli to the left volar forearm in healthy young males, with and without conditioning hot-water pain to the right hand. We found a CPM effect characterized by an initial increased activation in the orbitofrontal cortex (OFC) and amygdala at 250-300 ms poststimulus, which was correlated with the extent of psychophysical pain reduction. This was followed by reduced activations in the primary and secondary somatosensory cortices, supplementary motor area, posterior insula, and anterior cingulate cortex from 400 ms poststimulus. Our findings show that the prefrontal pain-controlling areas of OFC and amygdala increase their activity in parallel with subjective pain reduction under CPM, and that this increased activity occurs prior to reductions in activations of the pain sensory areas. In conclusion, achieving pain inhibition by the CPM process seems to be under control of the OFC and the amygdala. Copyright © 2011 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Cellulase activity and dissolved organic carbon release from lignocellulose macrophyte-derived in four trophic conditions.

PubMed

Bottino, Flávia; Cunha-Santino, Marcela Bianchessi; Bianchini, Irineu

2016-01-01

Considering the importance of lignocellulose macrophyte-derived for the energy flux in aquatic ecosystems and the nutrient concentrations as a function of force which influences the decomposition process, this study aims to relate the enzymatic activity and lignocellulose hydrolysis in different trophic statuses. Water samples and two macrophyte species were collected from the littoral zone of a subtropical Brazilian Reservoir. A lignocellulosic matrix was obtained using aqueous extraction of dried plant material (≈40°C). Incubations for decomposition of the lignocellulosic matrix were prepared using lignocelluloses, inoculums and filtered water simulating different trophic statuses with the same N:P ratio. The particulate organic carbon and dissolved organic carbon (POC and DOC, respectively) were quantified, the cellulase enzymatic activity was measured by releasing reducing sugars and immobilized carbon was analyzed by filtration. During the cellulose degradation indicated by the cellulase activity, the dissolved organic carbon daily rate and enzyme activity increased. It was related to a fast hydrolysable fraction of cellulose that contributed to short-term carbon immobilization (ca. 10 days). After approximately 20 days, the dissolved organic carbon and enzyme activity were inversely correlated suggesting that the respiration of microorganisms was responsible for carbon mineralization. Cellulose was an important resource in low nutrient conditions (oligotrophic). However, the detritus quality played a major role in the lignocelluloses degradation (i.e., enzyme activity) and carbon release. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Effects of γ-radiation on microbial load and antioxidant proprieties in green tea irradiated with different water activities

NASA Astrophysics Data System (ADS)

Fanaro, G. B.; Hassimotto, N. M. A.; Bastos, D. H. M.; Villavicencio, A. L. C. H.

2015-02-01

The aim of this paper is to study the effect of gamma radiation on green tea irradiated with different water activities. The green tea samples had their Aw adjusted to three values (0.93, 0.65, and 0.17) and were irradiated in 60Co source at doses of 0, 1.0, 1.5, 2.0, 2.5, 5.0, 7.5, and 10.0 kGy. The methods used were: microbiology, total phenolic compounds quantification, antioxidant activity by ORAC, and quantification of the main antioxidants. It was observed that the greater the amount of free water present in the samples, lower was the dose to achieve microbiological control. Despite the irradiation with 5.0 kGy with high water activity has a small decrease in phenolic compounds and in some catechins content, this condition is recommended once was the dose to ensure microbiological safety without interfering in the main catechins and the antioxidant activity.

On the Boundary Condition for Water at a Hydrophobic, Dense Surface

NASA Technical Reports Server (NTRS)

Walther, J. H.; Jaffe, R. L.; Werder, T.; Halicioglu, T.; Koumoutsakos, P.

2002-01-01

We study the no-slip boundary conditions for water at a hydrophobic (graphite) surface using non-equilibrium molecular-dynamics simulations. For the planar Couette flow, we find a slip length of 64 nm at 1 bar and 300 K, decreasing with increasing system pressure to a value of 31 nm at 1000 bar. Changing the properties of the interface to from hydrophobic to strongly hydrophilic reduces the slip to 14 nm. Finally, we study the flow of water past an array of carbon nanotubes mounted in an inline configuration with a spacing of 16.4 x 16.4 nm. For tube diameters of 1.25 and 2.50 nm we find drag coefficients in good agreement with the macroscopic, Navier-Stokes values. For carbon nanotubes, the no-slip condition is valid to within the definition of the position of the interface.

Pesticides water decontamination in oxygen-limited conditions.

PubMed

Suciu, Nicoleta Alina; Ferrari, Federico; Vasileiadis, Sotirios; Merli, Annalisa; Capri, Ettore; Trevisan, Marco

2013-01-01

This study was undertaken to develop a laboratory bioreactor, with a functioning principle similar with that of biobed systems but working in oxygen-limited conditions, suitable for decontaminating wastewater mixtures with pesticides. The system is composed by two cylindrical plastic containers. The first one, where the pesticides solution is collected, is open, whereas the second one, where the biomass is disposed, is closed. The pesticides solution was pumped at the biomass surface and subsequently recollected and disposed in the first container. Four pesticides with different physical-chemical characteristics were tested. The results obtained showed a relatively good capacity of the developed prototype to decontaminate waste water containing the mixture of pesticides. The time of the experiment, the number of cycles that the solution made in the system and the environmental temperature have a significantly influence for the decontamination of acetochlor and chlorpyrifos whereas for the decontamination of terbuthylazine and metalaxyl no significant influence was observed. Even if the present prototype could represent a valid solution to manage the water pesticides residues in a farm and to increase the confidence of bystanders and residents, the practical difficulties when replacing the biomass could represent a limit of the system.

Water in star-forming regions with Herschel (WISH). V. The physical conditions in low-mass protostellar outflows revealed by multi-transition water observations

NASA Astrophysics Data System (ADS)

Mottram, J. C.; Kristensen, L. E.; van Dishoeck, E. F.; Bruderer, S.; San José-García, I.; Karska, A.; Visser, R.; Santangelo, G.; Benz, A. O.; Bergin, E. A.; Caselli, P.; Herpin, F.; Hogerheijde, M. R.; Johnstone, D.; van Kempen, T. A.; Liseau, R.; Nisini, B.; Tafalla, M.; van der Tak, F. F. S.; Wyrowski, F.

2014-12-01

Context. Outflows are an important part of the star formation process as both the result of ongoing active accretion and one of the main sources of mechanical feedback on small scales. Water is the ideal tracer of these effects because it is present in high abundance for the conditions expected in various parts of the protostar, particularly the outflow. Aims: We constrain and quantify the physical conditions probed by water in the outflow-jet system for Class 0 and I sources. Methods: We present velocity-resolved Herschel HIFI spectra of multiple water-transitions observed towards 29 nearby Class 0/I protostars as part of the WISH guaranteed time key programme. The lines are decomposed into different Gaussian components, with each component related to one of three parts of the protostellar system; quiescent envelope, cavity shock and spot shocks in the jet and at the base of the outflow. We then use non-LTE radex models to constrain the excitation conditions present in the two outflow-related components. Results: Water emission at the source position is optically thick but effectively thin, with line ratios that do not vary with velocity, in contrast to CO. The physical conditions of the cavity and spot shocks are similar, with post-shock H2 densities of order 105 - 108 cm-3 and H2O column densities of order 1016 - 1018 cm-2. H2O emission originates in compact emitting regions: for the spot shocks these correspond to point sources with radii of order 10-200 AU, while for the cavity shocks these come from a thin layer along the outflow cavity wall with thickness of order 1-30 AU. Conclusions: Water emission at the source position traces two distinct kinematic components in the outflow; J shocks at the base of the outflow or in the jet, and C shocks in a thin layer in the cavity wall. The similarity of the physical conditions is in contrast to off-source determinations which show similar densities but lower column densities and larger filling factors. We propose

Water-Quality Conditions and Constituent Loads, Water Years 1996-2002, and Water-Quality Trends, Water Years 1983-2002, in the Scituate Reservoir Drainage Area, Rhode Island

USGS Publications Warehouse

Nimiroski, Mark T.; DeSimone, Leslie A.; Waldron, Marcus C.

2008-01-01

.62 nephelometric turbidity units and 4.8 mg/L as calcium carbonate, respectively. Indicator bacteria were detected in samples from all stations, but median concentrations were low, 23 and 9 colony-forming units per 100 mL for total coliform and E. coli bacteria, respectively. Median values of several physical properties and median concentrations of several constituents that can be related to human activities correlated positively with the percentages of developed land and correlated negatively with the percentages of forest cover in the drainage areas of the monitoring stations. Median concentrations of chloride also correlated positively with the density of roads in the drainage areas of monitoring stations, likely reflecting the effects of road-salt applications. Median values of color correlated positively with the percentages of wetlands in the drainage areas of monitoring stations, reflecting the natural sources of color in tributary stream waters. Negative correlations of turbidity, indicator bacteria, and chloride with streamflow likely reflect seasonal patterns, in which higher values and concentrations of these properties and constituents occur during low-flow conditions at the ends of water years. Similar seasonal patterns were observed for pH, alkalinity, and color. Loads and yields of chloride, nitrate, orthophosphate, and bacteria varied among monitoring stations in the Scituate Reservoir drainage area. Loads generally were higher at stations with larger drainage areas and at stations in the eastern, more developed parts of the Scituate Reservoir drainage area. Yields generally were higher at stations in the eastern parts of the drainage area. Upward trends in pH were identified for nearly half the monitoring stations and may reflect regional reductions in acid precipitation. Upward and downward trends were identified in chloride concentrations at various stations; upward trends may reflect the effects of increasing development, whereas strong downward trends at

Permanganate/bisulfite (PM/BS) conditioning-horizontal electro-dewatering (HED) of activated sludge: Effect of reactive Mn(III) species.

PubMed

Guo, Xinxin; Wang, Yili; Wang, Dongsheng

2017-11-01

A novel activated sludge (AS) conditioning method through permanganate/bisulfate (PM/BS) process was proposed. The method involved a new conditioner of reactive Mn(III) intermediate. Moreover, a Mn(III) conditioning-horizontal electro-dewatering (Mn(III) C-HED) process was established to improve AS dewatering performance. Underlying mechanisms were unraveled by investigating changes in physicochemical characteristics, scanning electron microscope (SEM) morphology, and transformation of water and organic matters. The optimum dewatering conditions for Mn(III) C-HED process with the final water content of 86.94% were determined as the combination of KMnO 4 0.01 mol/L AS and NaHSO 3 0.05 mol/L AS at 20 V for 120 min. Results showed that Mn(III) C-HED process effectively reduced free water and bound water with the corresponding removal ratios of 51.68% and 87.62% at the anode-side as well as 36.55% and 85.08% at the cathode-side, respectively. During the PM/BS process, the produced Mn(III), Mn 2+ , and MnO 2 exerted chemical and physical effects on AS conditioning and dewatering. Mn(III) disintegrated extracellular polymeric substances (EPS) fractions and cells in AS, as well as induced partial bound water release. Additionally, flocculation effect induced by Mn 2+ and MnO 2 skeleton building also benefited AS dewatering. AS cells were further disrupted under the effect of a horizontal electric field. Accordingly, EPS within the AS matrix was solubilized, tightly bound (TB)-EPS or loosely bound (LB)-EPS was converted to their corresponding outer EPS fractions, and AS dewaterability improved. Additionally, changes in pH and temperature at HED stage damaged the AS cells and changed the floc properties, thereby leading to easy separation of liquid and AS particles. Copyright © 2017 Elsevier Ltd. All rights reserved.

Core Muscle Activation During Unstable Bicep Curl Using a Water-Filled Instability Training Tube.

PubMed

Glass, Stephen C; Blanchette, Taylor W; Karwan, Lauren A; Pearson, Spencer S; OʼNeil, Allison P; Karlik, Dustin A

2016-11-01

Glass, SC, Blanchette, TW, Karwan, LA, Pearson, SS, O'Neil, AP, and Karlik, DA. Core muscle activation during unstable bicep curl using a water-filled instability training tube. J Strength Cond Res 30(11): 3212-3219, 2016-The purpose of this study was to assess compensatory muscle activation created during a bicep curl using a water-filled, unstable lifting tube. Ten men (age = 21 ± 1.6 years, height = 180.0 ± 3.3 cm, mass = 87.4 ± 15.0 kg) and 10 women (age = 19.6 ± 1.3 years, height = 161.4 ± 12.0 cm, mass = 61.2 ± 7.4 kg) completed bicep curls using an 11.4-kg tube partially filled with water during a 50% open-valve, 100% open, and control setting. Subjects completed 8 repetitions within each condition with integrated electromyographic signal (converted to percent maximal voluntary contraction) of the bicep, deltoid, rectus abdominus, and paraspinal muscles measured. Compensatory activation was determined using the natural log of coefficient of variation across concentric (CON) and eccentric (ECC) contractions. There were no differences between gender for any condition. Significant variability was seen across treatments for paraspinal muscles for CON and ECC at 50% (CON LnCV = 3.13 ± 0.56%, ECC LnCV = 3.34 ± 0.58%) and 100% (CON = 3.24 ± 0.34%, ECC = 3.46 ± 0.35%) compared with control (CON = 2.59 ± 0.47%, ECC = 2.80 ± 0.61%). Deltoid variability was greater at the 100% open setting (CON = 3.51 ± 0.53%, ECC = 3.56 ± 0.36%) compared with control (CON = 2.98 ± 0.35%, ECC = 2.97 ± 0.45%). The abdominal CON 100% showed variability (3.02 ± 0.47%) compared with control (2.65 ± 0.43%). Bicep activation remained unvaried. Compensatory activation of postural muscles contribute to postural stability. This device may be a useful tool for neuromuscular training leading to improved stability and control.

Hydrologic conditions in New Hampshire and Vermont, water year 2011

USGS Publications Warehouse

Kiah, Richard G.; Jarvis, Jason D.; Hegemann, Robert F.; Hilgendorf, Gregory S.; Ward, Sanborn L.

2013-01-01

Record-high hydrologic conditions in New Hampshire and Vermont occurred during water year 2011, according to data from 125 streamgages and lake gaging stations, 27 creststage gages, and 41 groundwater wells. Annual runoff for the 2011 water year was the sixth highest on record for New Hampshire and the highest on record for Vermont on the basis of a 111-year reference period (water years 1901–2011). Groundwater levels for the 2011 water year were generally normal in New Hampshire and normal to above normal in Vermont. Record flooding occurred in April, May, and August of water year 2011. Peak-of-record streamflows were recorded at 38 streamgages, 25 of which had more than 10 years of record. Flooding in April 2011 was widespread in parts of northern New Hampshire and Vermont; peak-of-record streamflows were recorded at nine streamgages. Flash flooding in May 2011 was isolated to central and northeastern Vermont; peakof- record streamflows were recorded at five streamgages. Devastating flooding in August 2011 occurred throughout most of Vermont and in parts of New Hampshire as a result of the heavy rains associated with Tropical Storm Irene. Peak-ofrecord streamflows were recorded at 24 streamgages.

Changes in Breath Trihalomethane Levels Resulting from Household Water-Use Activities

PubMed Central

Gordon, Sydney M.; Brinkman, Marielle C.; Ashley, David L.; Blount, Benjamin C.; Lyu, Christopher; Masters, John; Singer, Philip C.

2006-01-01

Common household water-use activities such as showering, bathing, drinking, and washing clothes or dishes are potentially important contributors to individual exposure to trihalomethanes (THMs), the major class of disinfection by-products of water treated with chlorine. Previous studies have focused on showering or bathing activities. In this study, we selected 12 common water-use activities and determined which may lead to the greatest THM exposures and result in the greatest increase in the internal dose. Seven subjects performed the various water-use activities in two residences served by water utilities with relatively high and moderate total THM levels. To maintain a consistent exposure environment, the activities, exposure times, air exchange rates, water flows, water temperatures, and extraneous THM emissions to the indoor air were carefully controlled. Water, indoor air, blood, and exhaled-breath samples were collected during each exposure session for each activity, in accordance with a strict, well-defined protocol. Although showering (for 10 min) and bathing (for 14 min), as well as machine washing of clothes and opening mechanical dishwashers at the end of the cycle, resulted in substantial increases in indoor air chloroform concentrations, only showering and bathing caused significant increases in the breath chloroform levels. In the case of bromodichloromethane (BDCM), only bathing yielded a significantly higher air level in relation to the preexposure concentration. For chloroform from showering, strong correlations were observed for indoor air and exhaled breath, blood and exhaled breath, indoor air and blood, and tap water and blood. Only water and breath, and blood and breath were significantly associated for chloroform from bathing. For BDCM, significant correlations were obtained for blood and air, and blood and water from showering. Neither dibromochloromethane nor bromoform gave measurable breath concentrations for any of the activities

Interactions between water activity and temperature on the Aspergillus flavus transcriptome and aflatoxin B1 production

USDA-ARS?s Scientific Manuscript database

The objectives of this study were to examine the effects of Aspergillus flavus colonization of maize kernels under different water activity (aw; 0.99 and 0.91) and temperature (30 and 37°C) conditions on (a) aflatoxin B1 (AFB1) production and (b) impacts on the transcriptome using RNAseq. This study...

Farmer Resettlements and Water Energy Stresses Arising From Aggravating Drought Conditions in Mahaweli River Watershed, Sri Lanka

NASA Astrophysics Data System (ADS)

Thabrew, L.

2012-12-01

Climate change is expected to cause significant changes in water quantity and water quality in river basins throughout the world, with particularly significant impacts in developing regions. Climate change effects are often exacerbated by other simultaneous activities in developing countries, such as population growth, reliance on subsistence agriculture, and expanding provision of electricity. Each of these activities requires access to readily-available freshwater. For example, population growth requires more water for irrigation as food production needs increase. Additionally, water is needed for generating electricity in hydropower facilities as well as other facilities, which require water to run steam turbines or to cool facilities. As such, many developing countries face the real and immediate need to anticipate and adapt to climatic stresses on water resources in both the agricultural and residential sectors. Water withdrawal in both of these sectors is largely driven by individual behaviors, such as electricity use in the home and irrigation practices on farmland, aggregated at the household, community, and regional level. Our ongoing project in Sri Lanka focuses on understanding aforementioned issues in coupled natural and human systems in the Mahaweli River Watershed (MWR) to inform decision-makers to streamline policies and strategies for effective adaptation to worsening drought conditions. MWR produces more than 60% of the rice demand and nearly 40% of the energy requirement of the country. Although irrigation is currently the sector that withdraws the most water, with government plans for resettling farmer communities and developing new urban centers in the region by 2030, electricity production is expected to compete for water against irrigation in the future. Thus, understanding the water-energy nexus is crucial to planning for conservation and efficiency. Through a pilot survey conducted by our interdisciplinary research team, in five locations in

Activities of the National Water-Quality Assessment Program in the upper Snake River Basin, Idaho and western Wyoming, 1991-2001

USGS Publications Warehouse

Low, Walton H.

1997-01-01

In 1991, the U.S. Geological Survey (USGS) began a full-scale National Water-Quality Assessment (NAWQA) Program. The long-term goals of the NAWQA Program are to describe the status and trends in the water quality of a large part of the Nation's rivers and aquifers and to improve understanding of the primary natural and human factors that affect water-quality conditions. In meeting these goals, the program will produce water-quality, ecological, and geographic information that will be useful to policy makers and managers at the national, State, and local levels. A major component of the program is study-unit investigations, upon which national-level assessment activities are based. The program's 60 study-unit investigations are associated with principal river basins and aquifer systems throughout the Nation. Study units encompass areas from 1,200 to more than 65,000 mi2 (square miles) and incorporate about 60 to 70 percent of the Nation's water use and population served by public water supply. In 1991, the upper Snake River Basin was among the first 20 NAWQA study units selected for implementation. From 1991 to 1995, a high-intensity data-collection phase of the upper Snake River Basin study unit (fig. 1) was implemented and completed. Components of this phase are described in a report by Gilliom and others (1995). In 1997, a low-intensity phase of data collection began, and work continued on data analysis, report writing, and data documentation and archiving activities that began in 1996. Principal data-collection activities during the low-intensity phase will include monitoring of surface-water and ground-water quality, assessment of aquatic biological conditions, and continued compilation of environmental setting information.

Influence of tap water quality and household water use activities on indoor air and internal dose levels of trihalomethanes.

PubMed

Nuckols, John R; Ashley, David L; Lyu, Christopher; Gordon, Sydney M; Hinckley, Alison F; Singer, Philip

2005-07-01

Individual exposure to trihalomethanes (THMs) in tap water can occur through ingestion, inhalation, or dermal exposure. Studies indicate that activities associated with inhaled or dermal exposure routes result in a greater increase in blood THM concentration than does ingestion. We measured blood and exhaled air concentrations of THM as biomarkers of exposure to participants conducting 14 common household water use activities, including ingestion of hot and cold tap water beverages, showering, clothes washing, hand washing, bathing, dish washing, and indirect shower exposure. We conducted our study at a single residence in each of two water utility service areas, one with relatively high and the other low total THM in the residence tap water. To maintain a consistent exposure environment for seven participants, we controlled water use activities, exposure time, air exchange, water flow and temperature, and nonstudy THM sources to the indoor air. We collected reference samples for water supply and air (pre-water use activity), as well as tap water and ambient air samples. We collected blood samples before and after each activity and exhaled breath samples at baseline and post-activity. All hot water use activities yielded a 2-fold increase in blood or breath THM concentrations for at least one individual. The greatest observed increase in blood and exhaled breath THM concentration in any participant was due to showering (direct and indirect), bathing, and hand dishwashing. Average increase in blood THM concentration ranged from 57 to 358 pg/mL due to these activities. More research is needed to determine whether acute and frequent exposures to THM at these concentrations have public health implications. Further research is also needed in designing epidemiologic studies that minimize data collection burden yet maximize accuracy in classification of dermal and inhalation THM exposure during hot water use activities.

Environmental water demand assessment under climate change conditions.

PubMed

Sarzaeim, Parisa; Bozorg-Haddad, Omid; Fallah-Mehdipour, Elahe; Loáiciga, Hugo A

2017-07-01

Measures taken to cope with the possible effects of climate change on water resources management are key for the successful adaptation to such change. This work assesses the environmental water demand of the Karkheh river in the reach comprising Karkheh dam to the Hoor-al-Azim wetland, Iran, under climate change during the period 2010-2059. The assessment of the environmental demand applies (1) representative concentration pathways (RCPs) and (2) downscaling methods. The first phase of this work projects temperature and rainfall in the period 2010-2059 under three RCPs and with two downscaling methods. Thus, six climatic scenarios are generated. The results showed that temperature and rainfall average would increase in the range of 1.7-5.2 and 1.9-9.2%, respectively. Subsequently, flows corresponding to the six different climatic scenarios are simulated with the unit hydrographs and component flows from rainfall, evaporation, and stream flow data (IHACRES) rainfall-runoff model and are input to the Karkheh reservoir. The simulation results indicated increases of 0.9-7.7% in the average flow under the six simulation scenarios during the period of analysis. The second phase of this paper's methodology determines the monthly minimum environmental water demands of the Karkheh river associated with the six simulation scenarios using a hydrological method. The determined environmental demands are compared with historical ones. The results show that the temporal variation of monthly environmental demand would change under climate change conditions. Furthermore, some climatic scenarios project environmental water demand larger than and some of them project less than the baseline one.

Biological filters and their use in potable water filtration systems in spaceflight conditions.

PubMed

Thornhill, Starla G; Kumar, Manish

2018-05-01

Providing drinking water to space missions such as the International Space Station (ISS) is a costly requirement for human habitation. To limit the costs of water transport, wastewater is collected and purified using a variety of physical and chemical means. To date, sand-based biofilters have been designed to function against gravity, and biofilms have been shown to form in microgravity conditions. Development of a universal silver-recycling biological filter system that is able to function in both microgravity and full gravity conditions would reduce the costs incurred in removing organic contaminants from wastewater by limiting the energy and chemical inputs required. This paper aims to propose the use of a sand-substrate biofilter to replace chemical means of water purification on manned spaceflights. Copyright © 2018 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.

Removal of micro pollutants using activated biochars and powdered activated carbon in water

NASA Astrophysics Data System (ADS)

Kim, E.; Jung, C.; Han, J.; Son, A.; Yoon, Y.

2015-12-01

Recent studies have suggested that emerging micropollutants containing endocrine disrupting compounds (EDCs); bisphenol A, 17 α-ethinylestradiol, 17 β-estradiol and pharmaceuticals and personal care products (PPCPs); sulfamethoxazole, carbamazepine, ibuprofen, atenolol, benzophenone, benzotriazole, caffeine, gemfibrozil, primidone, triclocarban in water have been linked to ecological impacts, even at trace concentrations (sub ug/L). Adsorption with adsorbent such as activated carbon having a high-binding affinity has been widely used to eliminate various contaminants in the aqueous phase. Recently, an efficient treatment strategy for EDCs and PPCPs has been considered by using cost effective adsorption particularly with biochar in aqueous environmentIn this study, the objective of this study is to determine the removal of 13 target EDCs/PPCPs having different physicochemical properties by a biochar at various water quality conditions (pH (3.5, 7, and 10.5), background ions (NaCl, CaCl2, Na₂SO₄), ionic strength, natural organic matter (NOM)). The activated biochar produced in a laboratory was also characterized by using conventional analytical methods as well as advanced solid-state nuclear magnetic resonance (NMR) techniques, which answer how these properties determine the competitive adsorption characteristics and mechanisms of EDCs and PPCPs.The primary findings suggest that micropollutants can be removed more effectively by the biochar than the commercially available powdered activated carbon. At pH values below the pKa of each compound, the adsorption affinity toward adsorbents increased significantly with the pH, whereas the adsorption affinity decreased significantly at the pH above the pKa values. Na+ did not significantly impact adsorption, while increasing the concentration of Ca2+lead to increase in the adsorption of these micropollutants. NOM adsorption with humic acids on these adsorbents disturbed adsorption capacity of the target compounds as

Estimating Chlorophyll Conditions in Southern New England Coastal Waters from Hyperspectral Aircraft Remote Sensing

EPA Science Inventory

Chlorophyll a (chl a) is commonly measured in water quality monitoring programs for coastal and freshwater systems. The concentration of chl a, when evaluated with other condition indicators such as water clarity and dissolved oxygen concentrations, provides information on the en...

Spatial variation in water quality within the water bodies of a Peak District catchment and the contribution of moorland condition

NASA Astrophysics Data System (ADS)

Crouch, Tia; Walker, Jonathan

2013-04-01

Spatial variation in water quality within the water bodies of a Peak District catchment and the contribution of moorland condition Tia Crouch and Jonathan Walker (Moors for the Future Partnership) Upland locations are significant water supply sources providing over 70% of fresh water in Great Britain. However, the peatlands of the Peak District, Southern Pennines are highly contaminated with anthropogenically derived, atmospherically deposited pollutants, such as heavy metals. This is due to their location between the cities of Manchester and Sheffield, the centre of the 19th century English Industrial Revolution. These peatlands are also severely eroded; therefore erosion could be releasing these pollutants into the fluvial system, representing a threat to both aquatic ecosystems and drinking water supplies. These threats are regulated under the Water Framework Directive (WFD) and the Water Supply Regulations respectively. There are two aims of this project. The first aim is to identify spatial and temporal variability of water quality within the Bamford water treatment works (WTW) catchment. This was achieved by fortnightly spot sampling at eight of the tributaries into the reservoir system. The second aim is to assess the contribution of moorland condition to water quality within the Bamford WTW catchment. Similarly, this was achieved by fortnightly spot sampling at eight moorland streams, draining from a variety of peatland conditions (bare peat, restoration, intact and heather burn). Water samples were analysed for carbon (DOC, POC & TOC), pH, hardness and a suite of heavy metals, including copper, iron and zinc. In addition, stream temperature and stage height was recorded. Preliminary results highlight a number of issues within the Bamford WTW catchment: under the WFD streams are not achieving 'good' status for pH, copper and zinc, and under the Drinking Water Standards (DWS) streams are not achieving targets for aluminium, iron and colour. For example, the

36 CFR 1002.63 - Boating and water use activities.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Boating and water use activities. 1002.63 Section 1002.63 Parks, Forests, and Public Property PRESIDIO TRUST RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 1002.63 Boating and water use activities. Swimming, boating and the use of...

Comparison of three approaches to model grapevine organogenesis in conditions of fluctuating temperature, solar radiation and soil water content.

PubMed

Pallas, B; Loi, C; Christophe, A; Cournède, P H; Lecoeur, J

2011-04-01

There is increasing interest in the development of plant growth models representing the complex system of interactions between the different determinants of plant development. These approaches are particularly relevant for grapevine organogenesis, which is a highly plastic process dependent on temperature, solar radiation, soil water deficit and trophic competition. The extent to which three plant growth models were able to deal with the observed plasticity of axis organogenesis was assessed. In the first model, axis organogenesis was dependent solely on temperature, through thermal time. In the second model, axis organogenesis was modelled through functional relationships linking meristem activity and trophic competition. In the last model, the rate of phytomer appearence on each axis was modelled as a function of both the trophic status of the plant and the direct effect of soil water content on potential meristem activity. The model including relationships between trophic competition and meristem behaviour involved a decrease in the root mean squared error (RMSE) for the simulations of organogenesis by a factor nine compared with the thermal time-based model. Compared with the model in which axis organogenesis was driven only by trophic competition, the implementation of relationships between water deficit and meristem behaviour improved organogenesis simulation results, resulting in a three times divided RMSE. The resulting model can be seen as a first attempt to build a comprehensive complete plant growth model simulating the development of the whole plant in fluctuating conditions of temperature, solar radiation and soil water content. We propose a new hypothesis concerning the effects of the different determinants of axis organogenesis. The rate of phytomer appearance according to thermal time was strongly affected by the plant trophic status and soil water deficit. Furthermore, the decrease in meristem activity when soil water is depleted does not result

Cadmium uptake and toxicity to water hyacinth: Effect of repeated exposures under controlled conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nir, R.; Gasith, A.; Perry, A.S.

1990-01-01

Water hyacinth, Eichornia crassipes has drawn attention as a plant of rapid growth and high biomass production, and capable of removing pollutants from domestic and industrial waste effluents. Most of the studies were static assays of short duration (1 to 3 days) and with a single exposure of the plants to cadmium. The authors presumed that repeated exposures to Cd might change the rate of uptake of the metal as well as the growth and physiological state of the plant. This prompted us to undertake the present study in order to evaluate the potential capacity of water hyacinth to removemore » Cd from solution under conditions of repeated exposures but otherwise favorable growth conditions and without interference from other toxic compounds. Removal of metal from effluents by plants is expected to be compounded by the influence of specific conditions of the medium such as temperature, pH, ionic strength, presence of other metals or complexing ligands. The results of the present study will serve as a comparative reference for evaluating the effect of effluent conditions on CD toxicity to water hyacinth and the plant's capacity for metal removal.« less

Volcanic Gases and Hot Spring Water to Evaluate the Volcanic Activity of the Mt. Baekdusan

NASA Astrophysics Data System (ADS)

Yun, S. H.; Lee, S.; Chang, C.

2017-12-01

This study performed the analysis on the volcanic gases and hot spring waters from the Julong hot spring at Mt. Baekdu, also known as Changbaishan on the North Korea(DPRK)-China border, during the period from July 2015 to August 2016. Also, we confirmed the errors that HCO3- concentrations of hot spring waters in the previous study (Lee et al. 2014) and tried to improve the problem. Dissolved CO2 in hot spring waters was analyzed using gas chromatograph in Lee et al.(2014). Improving this, from 2015, we used TOC-IC to analysis dissolved CO2. Also, we analyzed the Na2CO3 standard solutions of different concentrations using GC, and confirmed the correlation between the analytical concentrations and the real concentrations. However, because the analytical results of the Julong hot spring water were in discord with the estimated values based on this correlation, we can't estimate the HCO3-concentrations of 2014 samples. During the period of study, CO2/CH4 ratios in volcanic gases are gradually decreased, and this can be interpreted in two different ways. The first interpretation is that the conditions inside the volcanic edifice are changing into more reduction condition, and carbon in volcanic gases become more favorable to distribute into CH4 or CO than CO2. The second interpretation is that the interaction between volcanic gases and water becomes greater than past, and the concentrations of CO2which have much higher solubility in water decreased, relatively. In general, the effect of scrubbing of volcanic gas is strengthened during the quiet periods of volcanic activity rather than active periods. Meanwhile, the analysis of hot spring waters was done on the anion of acidic gases species, the major cations, and some trace elements (As, Cd, Re).This work was funded by the Korea Meteorological Administration Research and Development Program under Grant KMIPA 2015-3060.

Evaluation of the boundary condition influence on PAH concentrations in the water column during the sediment dredging of a port.

PubMed

Cutroneo, L; Castellano, M; Carbone, C; Consani, S; Gaino, F; Tucci, S; Magrì, S; Povero, P; Bertolotto, R M; Canepa, G; Capello, M

2015-12-30

The mobilisation of sediments and related contaminants connected to dredging activities is one of the most critical issues to the environmental risk and exposure assessment of a dredging project. The aim of this paper was an investigation of the mobilisation of polycyclic aromatic hydrocarbons (PAHs) due to the dredging of the Port of Genoa (Italy) to identify the temporal and spatial extent of the contaminant transport, and the influence of the dredging and the boundary conditions on it. The results showed relatively low background PAH concentrations in the water column and confirmed the dredging as the primary rising factor of concentrations in the water column, but also showed a complex scenario in which the different environmental and dredging factors forced the concentrations at different levels and moments. The post dredging phase showed PAH values close to the background conditions and the concentrations remained relatively high only for a few PAHs.

The features of element concentration in natural waters of the Kola North in conditions of environmental contamination

NASA Astrophysics Data System (ADS)

Bazova, Mariya; Moiseenko, Tatyana

2016-04-01

main processes that determine the conditions of residence and the behavior of elements in the water lakes. It was found that a key role in the formation of natural waters has the cumulative effect of landscape-geochemical conditions and anthropogenic impact. A great contribution, as shown by factorial analysis, make humic acid, which enhance the migratory activity elements. Jeffries D.S. (1997) Canadian acid rain assessment. Toronto. 3, 113 p. Moiseenko T.I. (1999) The fate of metals in Arctic surface waters: Method for defining critical levels Sci. Total Environ. 236, 19-39. Mannio J. (2001) Responces of headwater lakes to air pollution changes in Finland: Acad. Diss. Helsinki: Univ. Helsinki, 226 p. Moiseenko T.I., Gashkina N.A. (2007) Distribution of trace elements in surface waters and feature of their migration // Water resources. V. 34, № 4. P. 454-468. Moiseenko T.I. (2005) Water acidification and behavior of trace elements // Geochemistry. V.10. P.1120-1127. This work has done under the grant of the Russian Foundation of Fundamental Research (ofi_m) №15-29-06948 «The features formation of water quality conditions in Arctic regions of development mineral resources: algorithms settlements of permissible impact»

Annual summary of ground-water conditions in Arizona, Spring 1981 to Spring 1982

USGS Publications Warehouse

,

1982-01-01

The withdrawal of ground water was about 5.4 million acre-feet in Arizona in 1981, which is about 800,000 acre-feet more than the amount withdrawn in 1980. Most of the increase in 1981 was in the amount of ground water used for irrigation in the Basin and Range lowlands province. Through 1981, slightly more than 189 million acre-feet of ground water had been withdrawn from the ground-water reservoirs in Arizona. The report contains two small-scale maps that show ground-water pumpage by areas and the status of the ground-water inventory in the State. The main map, which is at a scale of 1:500,000, shows potential well production, depth to water in selected wells in spring 1982, and change in water level in selected wells from 1977 to 1982. A brief text summarizes the current ground-water conditions in the State. (USGS)

Influence of Tap Water Quality and Household Water Use Activities on Indoor Air and Internal Dose Levels of Trihalomethanes

PubMed Central

Nuckols, John R.; Ashley, David L.; Lyu, Christopher; Gordon, Sydney M.; Hinckley, Alison F.; Singer, Philip

2005-01-01

Individual exposure to trihalomethanes (THMs) in tap water can occur through ingestion, inhalation, or dermal exposure. Studies indicate that activities associated with inhaled or dermal exposure routes result in a greater increase in blood THM concentration than does ingestion. We measured blood and exhaled air concentrations of THM as biomarkers of exposure to participants conducting 14 common household water use activities, including ingestion of hot and cold tap water beverages, showering, clothes washing, hand washing, bathing, dish washing, and indirect shower exposure. We conducted our study at a single residence in each of two water utility service areas, one with relatively high and the other low total THM in the residence tap water. To maintain a consistent exposure environment for seven participants, we controlled water use activities, exposure time, air exchange, water flow and temperature, and nonstudy THM sources to the indoor air. We collected reference samples for water supply and air (pre–water use activity), as well as tap water and ambient air samples. We collected blood samples before and after each activity and exhaled breath samples at baseline and postactivity. All hot water use activities yielded a 2-fold increase in blood or breath THM concentrations for at least one individual. The greatest observed increase in blood and exhaled breath THM concentration in any participant was due to showering (direct and indirect), bathing, and hand dishwashing. Average increase in blood THM concentration ranged from 57 to 358 pg/mL due to these activities. More research is needed to determine whether acute and frequent exposures to THM at these concentrations have public health implications. Further research is also needed in designing epidemiologic studies that minimize data collection burden yet maximize accuracy in classification of dermal and inhalation THM exposure during hot water use activities. PMID:16002374

Ice nucleation activity of diesel soot particles at cirrus relevant temperature conditions: Effects of hydration, secondary organics coating, soot morphology, and coagulation

NASA Astrophysics Data System (ADS)

Kulkarni, Gourihar; China, Swarup; Liu, Shang; Nandasiri, Manjula; Sharma, Noopur; Wilson, Jacqueline; Aiken, Allison C.; Chand, Duli; Laskin, Alexander; Mazzoleni, Claudio; Pekour, Mikhail; Shilling, John; Shutthanandan, Vaithiyalingam; Zelenyuk, Alla; Zaveri, Rahul A.

2016-04-01

Ice formation by diesel soot particles was investigated at temperatures ranging from -40 to -50°C. Size-selected soot particles were physically and chemically aged in an environmental chamber, and their ice nucleating properties were determined using a continuous flow diffusion type ice nucleation chamber. Bare (freshly formed), hydrated, and compacted soot particles, as well as α-pinene secondary organic aerosol (SOA)-coated soot particles at high relative humidity conditions, showed ice formation activity at subsaturation conditions with respect to water but below the homogeneous freezing threshold conditions. However, SOA-coated soot particles at dry conditions were observed to freeze at homogeneous freezing threshold conditions. Overall, our results suggest that heterogeneous ice nucleation activity of freshly emitted diesel soot particles are sensitive to some of the aging processes that soot can undergo in the atmosphere.

Annual summary of ground-water conditions in Arizona, spring 1982 to spring 1983

USGS Publications Warehouse

,

1984-01-01

The withdrawal of ground water was slightly less than 4.2 million acre-feet in Arizona in 1982, which is about 1.2 million acre-feet less than the amount withdrawn in 1981. Most of the decrease in 1982 was in the amount of ground water used for irrigation in the Basin and Range lowlands province. Through 1982, slightly more than 193 million acre-feet of ground water had been withdrawn from the ground-water reservoirs in Arizona. The report contains three small-scale maps that show ground-water pumpage by areas, the status of the ground-water inventory and observation-well program, and the ground-water quality sampling program. The main map, which is at a scale of 1:500,000, shows potential well production, depth to water in selected wells in spring 1983, and change in water level in selected wells from 1978 to 1983. A brief text summarizes the current ground-water conditions in the State. (USGS)

[Effects of quantum nonlocality in the water activation process].

PubMed

Zatsepina, O V; Stekhin, A A; Yakovleva, G V

2014-01-01

The dynamic alterations of the magnetic flux density of the water volume, activated with structurally stressed calcium carbonate in micellar form have been investigated. The phase of the associated water was established to exhibit electrical and magnetic properties, recorded by in B&E meter in the frequency range of 5Hz - 2kHz. Alterations in water Eh (redox) potential and the magnetic flux density B testify to synchronous auto-oscillatory changes. This gives evidence of non-linearity of the relationship between auto-oscillatory processes excited in the water; and reflects the nonlocal in time the relationship between the states of water, manifesting in a change of water activity on the 1st and 2nd day in negative time. The mechanism of action of associated water phase is shown to be described by de Broglie concept of matter waves with taking into account delocalized in time states of phase of electron wave packet in accordance with the transactional interpretation of quantum physics.

COMETABOLISM OF TRIHALOMETHANES BY NITRIFYING BIOFILTERS UNDER DRINKING WATER TREATMENT PLANT CONDITIONS

EPA Science Inventory

EPA Identifier: FP916412
Title: Cometabolism of Trihalomethanes by Nitrifying Biofilters Under Drinking Water Treatment Plant Conditions
Fellow (Principal Investigator): David G. Wahman
Institution: University of Texas at Austin
EPA ...

Ground-water conditions between Oracle and Oracle Junction, Pinal County, Arizona

USGS Publications Warehouse

Heindl, L.A.

1955-01-01

The development of the San Manuel copper prospect has greatly increased traffic along State Highway 77. Considerable interest in commercial possibilities along that road has resulted in a request by the Arizona State Land Department for information about the ground-water conditions between Oracle and Oracle Junction. This request came too late for information to be included in a recently completed memorandum report on the occurrence of ground water in the vicinity of Oracle, released in February 1955. These data are presented as a supplement to that report to minimized duplication of statements about the general geologic and hydrologic conditions. The necessary well data and sample descriptions that were not included in the Oracle report are shown in tables 3 and 4. The area discussed in this supplement comprises parts of Tps. 9 and 10 S., Rs. 13, 14, and 15 E., and includes about 90 square miles (fig. 3). The eastern portion overlaps part of the area covered by the earlier report.

Reforming of glucose and wood at the critical conditions of water

NASA Technical Reports Server (NTRS)

Modell, M.

1977-01-01

Reforming of organics in aqueous solutions is being investigated as a potential waste treatment process. Earlier studies showed that glucose in water reacts to form a gaseous mixture of CO, H2, CH4, CO2, C2H6, and C2H4 in the vicinity of the critical conditions of water (374 C, 22 MPa). The earlier work has been extended to determine the effect of variations in temperature and feed concentration on the extent of gasification. The percent gasification decreases with increasing feed concentration, indicating an overall kinetic order less than unity. Surprisingly, the percent gasification decreases with increasing temperature. A number of preliminary experiments were conducted with maple sawdust feed, which was thought to be representative of complex organic wastes from paper and vegetable matter. Once again, no solid products were found under the critical conditions; the percent gasification ranged from 16 to 88 percent, depending on the feed composition and residence time.

Deuterium used as artificial tracer in column studies under saturated water flow conditions

NASA Astrophysics Data System (ADS)

Koeniger, P.; Geiges, M.; Leibundgut, Ch.

2003-04-01

In contrast to numerous investigations using deuterium as an environmental tracer, hydrological investigations with deuterium-labelled water are rather rare. Currently applications in groundwater studies are restricted due to increasing costs of spiking large water quantities but an application as intelligent tracer might be of advantage especially in combination with other tracers and under distinct environmental conditions. Therefore deuterium was applied as artificial tracer in column experiments that are well proved as a tool to characterise tracer behaviour in recent studies. Deuterium was tested in comparison to the more familiar conservative tracer fluorescein. Varying experimental conditions, e.g. column length (0.5, 1.0, 1.5 m), initial tracer concentration (0.01, 0.02, 0.2 mg) and flow velocity (1.5 to 6.0 m/d) were used to investigate tracer behaviour under saturated water flow conditions. Deuterium was analysed using an H/Device with chrome reduction connected to an isotope ratio mass spectrometer and expressed in relative concentrations [per mill V-SMOW]. Theoretical tracer breakthrough curves were calculated using a one dimensional dispersion model. The results indicate higher mean transport velocities and smaller dispersion for deuterium in all experiments. Due to different molecule properties that also determine the interaction of soil substrate and tracer, deuterium indicates a more conservative transport behaviour. Deuterium is non-toxic, completely soluble, chemically and biologically stable and not subject to light-influenced decay. Furthermore, it shows promise for investigations of water flow in the unsaturated zone, and of interactions of water in soil-plant-atmosphere systems. A further discussion of problems, together with possibilities for applying deuterium as an artificial tracer, will be presented.

Water-quality effects on Baker Lake of recent volcanic activity at Mount Baker, Washington

USGS Publications Warehouse

Bortleson, Gilbert Carl; Wilson, Reed T.; Foxworthy, B.L.

1976-01-01

, mineral-rich inflow depend mainly on: (1) the rate of flow and the character of Boulder Creek water at the time; (2) the relative rate of inflow of the feedwater from other streams; and (3) whether the reservoir is temperature-stratified (summer) or homothermal (winter). A distinct layer of Boulder Creek water was found in the lake in September 1975 extending at least 0.3 miles (.5 km) downreservoir. The greatest opportunity for water from Boulder Creek to persist as a layer and extend farthest before mixing with the other reservoir water is when Baker Lake is strongly stratified and Boulder Creek flow rate is large in relation to other feedwater. Baker Lake probably could assimilate indefinitely the acid loads measured during 1975, by dilution, chemical neutralization, and buffering of the acid-rich Boulder creek water. Minor elements found in Boulder Creek water included arsenic, selenium, and mercury; however, none of these would reach the limits recommended by the U.S. Environmental Protection Agency for public water supplies unless their concentrations increased to several times the amounts found during this study. Under the prevailing conditions, acid-rich Boulder Creek water apparently cannot accumulate as a pool, or persist as a layer long enough to reach Upper Baker Dam and attack the concrete. However, even if the acid load from Boulder Creek does not greatly increase, occasional light fish mortalities may result near the mouth of the creek. Greater acid and mineral loads, resulting from further increases in volcanic activity or other possible causes, could be more harmful, especially to the fish. Continued monitoring of Boulder Creek flow and water quality is needed to rapidly any changes in conditions at Sherman Crater, and to provide warning of possible greater impacts on Baker Lake from any future increases in Mount Baker activity.

Shielding activated return water at the ESS

NASA Astrophysics Data System (ADS)

Klinkby, Esben; Muhrer, Günter; Carlsson, H.; Eriksson, Björn

2018-06-01

ESS utilises water both for moderating neutrons to thermal energies, as well as to cool beryllium- and steel reflectors, the shielding and plugs. This means that the water, in separate loops, will be subject to a significant proton and neutron irradiation causing the water to activate. After irradiation, the water is led to delay tanks situated inside the target building. Before returned to the target monolith ∼ 10% is led to the ion exchanger. This paper aims at determining the shielding required to ensure that the biological dose-rate requirements in the target building and neighbouring instrument halls are met during operation of facility.

Ground-water conditions and geologic reconnaissance of the Upper Sevier River basin, Utah

USGS Publications Warehouse

Carpenter, Carl H.; Robinson, Gerald B.; Bjorklund, Louis Jay

1967-01-01

The upper Sevier River basin is in south-central Utah and includes an area of about 2,400 .square miles of high plateaus and valleys. It comprises the entire Sevier River drainage basin above Kingston, including the East Fork Sevier River and its tributaries. The basin was investigated to determine general ground-water conditions, the interrelation of ground water and surface water, the effects of increasing the pumping of ground water, and the amount of ground water in storage.The basin includes four main valleys - Panguitch Valley, Circle Valley, East Fork Valley, and Grass Valley - which are drained by the Sevier River, the East Fork Sevier River, and Otter Creek. The plateaus surrounding the valleys consist of sedimentary and igneous rocks that range in age from Triassic to Quaternary. The valley fill, which is predominantly alluvial gravel, sand, silt, and clay, has a maximum thickness of more than 800 feet.The four main valleys constitute separate ground-water basins. East Fork Valley basin is divided into Emery Valley, Johns Valley, and Antimony subbasins, and Grass Valley basin is divided into Koosharem and Angle subbasins. Ground water occurs under both artesian and water-table conditions in all the basins and subbasins except Johns Valley, Emery Valley, and Angle subbasins, where water is only under water-table conditions. The water is under artesian pressure in beds of gravel and sand confined by overlying beds of silt and clay in the downstream parts of Panguitch Valley basin, Circle Valley basin, and Antimony subbasin, and in most of Koosharem subbasin. Along the sides and upstream ends of these basins, water is usually under water-table conditions.About 1 million acre-feet of ground water that is readily available to wells is stored in the gravel and sand of the upper 200 feet of saturated valley fill. About 570,000 acre-feet is stored in Panguitch Valley basin, about 210,000 in Circle Valley basin, about 6,000 in Emery Valley subbasin, about 90

Effect of environmental conditions on variation in the sediment-water interface created by complex macrofaunal burrows on a tidal flat

NASA Astrophysics Data System (ADS)

Koo, Bon Joo; Kwon, Kae Kyoung; Hyun, Jung-Ho

2007-11-01

We quantified the increase in the sediment-water interface created by the burrowing activities of the resident macrofaunal community and its variation with respect to the physical conditions of the habitat on a tidal fat. We investigated environmental factors and dimensions of macrofaunal burrows with respect to tidal height and vegetation during spring and summer at three sites. A resin-casting method was used to quantify the dimensions of all burrows at each site. The dimensions of macrofaunal burrows varied both temporally and spatially and the increase in the sediment-water interface reached a maximum of 311%, ranging from 20 to 255% under different habitat conditions. The sediment-water interface depended on the duration of exposure resulting from tidal height, increased temperatures resulting from seasonality, and marsh plant density. Burrows were deeper and more expansive at both higher tidal levels and higher temperatures in summer. Burrow dimensions were sharply reduced with the disappearance of adult macrofauna in areas where the roots of the marsh plant Suaeda japonica were dense. The significance of this study lies in quantifying the burrow dimensions of the entire macrofaunal community, rather than just a single population, and confirming their spatial and temporal variation with respect to physical conditions of the habitat. Environmental factors responsible for variation in burrow dimensions are discussed.

Changes in the lower boundary condition of water fluxes in the NOAH land surface scheme

NASA Astrophysics Data System (ADS)

Lohmann, D.; Peters-Lidard, C. D.

2002-05-01

One problem with current land surface schemes (LSS) used in weather prediction and climate models is their inabilty to reproduce streamflow in large river basins. This can be attributed to the weak representation of their upper (infiltration) and lower (baseflow) boundary conditions in their water balance / transport equations. Operational (traditional) hydrological models, which operate on the same spatial scale as a LSS, on the other hand, are able to reproduce streamflow time series. Their infiltration and baseflow equations are often empirically based and therefore have been neglected by the LSS community. It must be argued that we need to include a better representation of long time scales (as represented by groundwater and baseflow) into the current LSS to make valuable predictions of streamflow and water resources. This talk concentrates on the lower boundary condition of water fluxes within LSS. It reviews briefly previous attempts to incorporate groundwater and more realistic lower boundary conditions into LSS and summarizes the effect on the runoff (baseflow) production time scales as compared to currently used lower boundary conditions in LSS. The NOAH - LSM in the LDAS and DMIP setting is used to introduce a simplified groundwater model, based on the linearized Boussinesq equation, and the TOPMODEL. The NOAH - LSM will be coupled to a linear routing model to investigate the effects of the new lower boundary condition on the water balance (in particular, streamflow) in small to medium sized catchments in the LDAS / DMIP domain.

Hydrologic conditions, recharge, and baseline water quality of the surficial aquifer system at Jekyll Island, Georgia, 2012-13

USGS Publications Warehouse

Gordon, Debbie W.; Torak, Lynn J.

2016-03-08

Groundwater levels and specific-conductance measurements showed the dependence of freshwater resources on rainfall to recharge the water-table zone of the surficial aquifer system and to influence groundwater flow on Jekyll Island. The unseasonably dry conditions during November 2012 to April 2013 induced saline water infiltration to the water-table zone from the marshland separating the Jekyll River from the island. A strong correlation (R2 = 0.97) of specific conductance to chloride concentration in water samples from wells installed in the water-table zone provided support for the determination of seasonal directions of groundwater flow by confirming salinity changes in the water-table zone. Unseasonably wet conditions during the late spring to August caused groundwater-flow reversals in some areas. The high dependence of the water-table zone in the surficial aquifer system on precipitation to replenish the aquifer with freshwater underscored the importance of monitoring groundwater levels, water quality, and water use to identify aquifer-discharge conditions that have the potential to promote seawater encroachment and degrade freshwater resources on Jekyll Island.

Army Corps of Engineers: Water Resource Authorizations, Appropriations, and Activities

DTIC Science & Technology

2017-02-27

of Engineers: Water Resource Authorizations, Appropriations, and Activities Congressional Research Service Summary The U.S. Army Corps of......Engineers: Water Resource Authorizations, Appropriations, and Activities Congressional Research Service 1 Army Corps of Engineers The U.S. Army Corps of

Water quality degradation effects on freshwater availability: Impacts to human activities

USGS Publications Warehouse

Peters, N.E.; Meybeck, Michel

2000-01-01

The quality of freshwater at any point on the landscape reflects the combined effects of many processes along water pathways. Human activities on all spatial scales affect both water quality and quantity. Alteration of the landscape and associated vegetation has not only changed the water balance, but typically has altered processes that control water quality. Effects of human activities on a small scale are relevant to an entire drainage basin. Furthermore, local, regional, and global differences in climate and water flow are considerable, causing varying effects of human activities on land and water quality and quantity, depending on location within a watershed, geology, biology, physiographic characteristics, and climate. These natural characteristics also greatly control human activities, which will, in turn, modify (or affect) the natural composition of water. One of the most important issues for effective resource management is recognition of cyclical and cascading effects of human activities on the water quality and quantity along hydrologic pathways. The degradation of water quality in one part of a watershed can have negative effects on users downstream. Everyone lives downstream of the effects of some human activity. An extremely important factor is that substances added to the atmosphere, land, and water generally have relatively long time scales for removal or clean up. The nature of the substance, including its affinity for adhering to soil and its ability to be transformed, affects the mobility and the time scale for removal of the substance. Policy alone will not solve many of the degradation issues, but a combination of policy, education, scientific knowledge, planning, and enforcement of applicable laws can provide mechanisms for slowing the rate of degradation and provide human and environmental protection. Such an integrated approach is needed to effectively manage land and water resources.

Novel Co(II) phthalocyanines of extended periphery and their water-soluble derivatives. Synthesis, spectral properties and catalytic activity

NASA Astrophysics Data System (ADS)

Filippova, Anna; Vashurin, Artur; Znoyko, Serafima; Kuzmin, Ilya; Razumov, Mikhail; Chernova, Alena; Shaposhnikov, Gennady; Koifman, Oscar

2017-12-01

Novel complexes of cobalt and copper with substituted phthalocyanines were synthesized and characterized. Their water-soluble derivatives were obtained by sulfonation under mild conditions and structurally proved. Aggregation equilibrium in water mediums was shown and influence of geometrical and electron parameters of macroheterocycle peripheral substituents on these processes was established. Catalytic activity upon liquid-phase oxidation of N,N-diethylcarbamodithiolate to thiuram E was studied. Kinetic parameters of substrate oxidation in presence of cobalt phthalocyanines were considered.

The hippocampus and appetitive Pavlovian conditioning: effects of excitotoxic hippocampal lesions on conditioned locomotor activity and autoshaping.

PubMed

Ito, Rutsuko; Everitt, Barry J; Robbins, Trevor W

2005-01-01

The hippocampus (HPC) is known to be critically involved in the formation of associations between contextual/spatial stimuli and behaviorally significant events, playing a pivotal role in learning and memory. However, increasing evidence indicates that the HPC is also essential for more basic motivational processes. The amygdala, by contrast, is important for learning about the motivational significance of discrete cues. This study investigated the effects of excitotoxic lesions of the rat HPC and the basolateral amygdala (BLA) on the acquisition of a number of appetitive behaviors known to be dependent on the formation of Pavlovian associations between a reward (food) and discrete stimuli or contexts: (1) conditioned/anticipatory locomotor activity to food delivered in a specific context and (2) autoshaping, where rats learn to show conditioned discriminated approach to a discrete visual CS+. While BLA lesions had minimal effects on conditioned locomotor activity, hippocampal lesions facilitated the development of both conditioned activity to food and autoshaping behavior, suggesting that hippocampal lesions may have increased the incentive motivational properties of food and associated conditioned stimuli, consistent with the hypothesis that the HPC is involved in inhibitory processes in appetitive conditioning. (c) 2005 Wiley-Liss, Inc.

Biological iron oxidation by Gallionella spp. in drinking water production under fully aerated conditions.

PubMed

de Vet, W W J M; Dinkla, I J T; Rietveld, L C; van Loosdrecht, M C M

2011-11-01

Iron oxidation under neutral conditions (pH 6.5-8) may be a homo- or heterogeneous chemically- or a biologically-mediated process. The chemical oxidation is supposed to outpace the biological process under slightly alkaline conditions (pH 7-8). The iron oxidation kinetics and growth of Gallionella spp. - obligatory chemolithotrophic iron oxidizers - were assessed in natural, organic carbon-containing water, in continuous lab-scale reactors and full-scale groundwater trickling filters in the Netherlands. From Gallionella cell numbers determined by qPCR, balances were made for all systems. The homogeneous chemical iron oxidation occurred in accordance with the literature, but was retarded by a low water temperature (13 °C). The contribution of the heterogeneous chemical oxidation was, despite the presence of freshly formed iron oxyhydroxides, much lower than in previous studies in ultrapure water. This could be caused by the adsorption of natural organic matter (NOM) on the iron oxide surfaces. In the oxygen-saturated natural water with a pH ranging from 6.5 to 7.7, Gallionella spp. grew uninhibited and biological iron oxidation was an important, and probably the dominant, process. Gallionella growth was not even inhibited in a full-scale filter after plate aeration. From this we conclude that Gallionella spp. can grow under neutral pH and fully aerated conditions when the chemical iron oxidation is retarded by low water temperature and inhibition of the autocatalytic iron oxidation. Copyright © 2011 Elsevier Ltd. All rights reserved.

Wetlands monitoring - hydrological conditions and water quality in selected transects of Biebrza National Park.

NASA Astrophysics Data System (ADS)

Stelmaszczyk, Mateusz; Okruszko, Tomasz

2010-05-01

Water Framework Directive (WFD) obligates Member States to prevent further deterioration as well as to protect and enhance the status of aquatic ecosystems and wetlands. In order to fulfill one of the WFD objectives - to keep wetlands in good surface water and groundwater status (determined by good ecological, chemical and quantitative status) it is necessary to specify most favourable conditions for them. In that case monitoring of factors responsible for wetlands status in natural areas is a key issue. Further, achieved knowledge of existing relations in ecosystems can be implemented in protection and restoration projects. There are a number of factors influencing diversity of habitats responsible for developing different wetland ecosystems and their sustaining in good ecological status. It's believed that among significant factors such as hydrological conditions, water quality, nutrient availability in the soil, pH value and management (e.g. grazing, mowing) the hydrological conditions are the most important. In presented work authors concentrated on hydrological conditions and water quality and theirs influence on wetland vegetation of Biebrza National Park (BNP). BNP located north-east part of Poland is recognized by many scientist as a unique undisturbed wetland reference area. Five transects located in different basins of BNP were chosen. Transects consist of piezometers in which the water table levels and water quality were measured. Analysis of electroconductivity (EC), alkalinity (HCO3-) and pH were done directly in the field. In the laboratory anions (NO3-, PO43-, Cl-, SO42-) and cations (NH4+, Ca2+, Mg2+, Br+, Li+, Na+, K+) concentration was determined using High Performance Liquid Chromatography (HPLC). D-divers, electronic devices to permanent measurement of groundwater level changes were located in some of the piezometers. Piezometers were located in the sites characterized by different hydrological conditions, from groundwater fed to river fed areas

The influence of water-soluble As(III) and As(V) on dehydrogenase activity in soils affected by mine tailings.

PubMed

Fernández, Pilar; Sommer, Irene; Cram, Silke; Rosas, Irma; Gutiérrez, Margarita

2005-09-15

Dehydrogenase activity (DHA) in soils contaminated by arsenic-bearing tailings was correlated with total arsenic and total water-soluble arsenic (As(III)+As(V)) to evaluate the impact of tailings dispersion on the oxidative capacity of soil microorganisms. Georeferenced surface soil samples (0-10 cm depth) were collected at different distances from a tailings dam. In the samples farthest from the dam, all water-soluble arsenic (avg. 0.6+/-0.1 mg kg(-1)) was As(V). The highest concentration of water-soluble As(III)+As(V) (>1.9 mg kg(-1)) was found where As(III) was present. DHA averaged 438.9+/-79.3 microg INTF g(-1) h(-1) at the greatest distance from the dam and decreased to 92.3+/-27.1 microg INTF g(-1) h(-1) with decreasing distance from the dam. Pearson correlation coefficient between DHA and samples containing water-soluble As(V) (r=-0.87) was greater than that between DHA and total water-soluble arsenic (r=-0.57). The correlation between DHA and soluble arsenic containing both As(V) and As(III) was not significant (r=0.24). In soils with detectable As(III) concentrations where wet conditions prevail (i.e., reducing conditions), there is an abiotic response in addition to a biotic one. The correlation between DHA and total water-soluble As(III)+ As(V) was higher (r=-0.79) when the abiotic response was excluded. Our study demonstrated the importance of distinguishing between total and available fraction and its species and the need to evaluate biological functions in addition to purely geochemical analyses. DHA bioassay combined with other microbial properties offers a good tool for evaluating soil microbial activity and status and is a suitable indicator of the oxidative capacity of soil microorganisms affected by tailings in an oxidizing environment; however, under reducing conditions, abiotic responses must also be studied.

How Does the Gibbs Inequality Condition Affect the Stability and Detachment of Floating Spheres from the Free Surface of Water?

PubMed

Feng, Dong-xia; Nguyen, Anh V

2016-03-01

Floating objects on the air-water interfaces are central to a number of everyday activities, from walking on water by insects to flotation separation of valuable minerals using air bubbles. The available theories show that a fine sphere can float if the force of surface tension and buoyancies can support the sphere at the interface with an apical angle subtended by the circle of contact being larger than the contact angle. Here we show that the pinning of the contact line at the sharp edge, known as the Gibbs inequality condition, also plays a significant role in controlling the stability and detachment of floating spheres. Specifically, we truncated the spheres with different angles and used a force sensor device to measure the force of pushing the truncated spheres from the interface into water. We also developed a theoretical modeling to calculate the pushing force that in combination with experimental results shows different effects of the Gibbs inequality condition on the stability and detachment of the spheres from the water surface. For small angles of truncation, the Gibbs inequality condition does not affect the sphere detachment, and hence the classical theories on the floatability of spheres are valid. For large truncated angles, the Gibbs inequality condition determines the tenacity of the particle-meniscus contact and the stability and detachment of floating spheres. In this case, the classical theories on the floatability of spheres are no longer valid. A critical truncated angle for the transition from the classical to the Gibbs inequality regimes of detachment was also established. The outcomes of this research advance our understanding of the behavior of floating objects, in particular, the flotation separation of valuable minerals, which often contain various sharp edges of their crystal faces.

Fluctuating water depths affect American alligator (Alligator mississippiensis) body condition in the Everglades, Florida, USA

USGS Publications Warehouse

Brandt, Laura A.; Beauchamp, Jeffrey S.; Jeffery, Brian M.; Cherkiss, Michael S.; Mazzotti, Frank J.

2016-01-01

Successful restoration of wetland ecosystems requires knowledge of wetland hydrologic patterns and an understanding of how those patterns affect wetland plant and animal populations.Within the Everglades, Florida, USA restoration, an applied science strategy including conceptual ecological models linking drivers to indicators is being used to organize current scientific understanding to support restoration efforts. A key driver of the ecosystem affecting the distribution and abundance of organisms is the timing, distribution, and volume of water flows that result in water depth patterns across the landscape. American alligators (Alligator mississippiensis) are one of the ecological indicators being used to assess Everglades restoration because they are a keystone species and integrate biological impacts of hydrological operations through all life stages. Alligator body condition (the relative fatness of an animal) is one of the metrics being used and targets have been set to allow us to track progress. We examined trends in alligator body condition using Fulton’s K over a 15 year period (2000–2014) at seven different wetland areas within the Everglades ecosystem, assessed patterns and trends relative to restoration targets, and related those trends to hydrologic variables. We developed a series of 17 a priori hypotheses that we tested with an information theoretic approach to identify which hydrologic factors affect alligator body condition. Alligator body condition was highest throughout the Everglades during the early 2000s and is approximately 5–10% lower now (2014). Values have varied by year, area, and hydrology. Body condition was positively correlated with range in water depth and fall water depth. Our top model was the “Current” model and included variables that describe current year hydrology (spring depth, fall depth, hydroperiod, range, interaction of range and fall depth, interaction of range and hydroperiod). Across all models, interaction

Water-temperature data acquisition activities in the United States

USGS Publications Warehouse

Pauszek, F.H.

1972-01-01

Along with the growing interest in water quality during the last decade, the need for data on all types of water-quality parameters has also increased. One parameter of particular interest, because of its many ramifications, is temperature. It influences many of the chemical and physical processes that take place in water. The solubility of gases--for example, oxygen and carbon dioxide--and the solution of mineral matter in water are functions of temperature. Such physical properties as density and viscosity vary with temperature. Oxidation of organic materials, as well as algal and bacterial growth, is promoted or retarded by favorable or unfavorable temperatures. Further, temperature bears on the utility of water: as a source of public water supplies; for industrial use, particularly if the water is used for cooling; and in the field of recreation involving contact sports, fishing, and fish culture. In recent years, temperature changes resulting from inflow of heated industrial waste, particularly effluent from power generating plants, have increased the need for temperature data to determine the degree of change, its effect on ecology, and the effect of any remedial action. Thus, because of the many extensive and intensive effects, a large amount of temperature data is collected on surface and ground waters by many agencies throughout the country. Moreover, because of its importance, there is a widespread interest in temperature even by those who are not active collectors of the data themselves. The industrialist, the manager, the public official, and others at one time or another may have need for temperature data and may well raise the questions: Who is collecting temperature data? What is the extent of the activity? Where are the data being collected? The purpose of this report is to answer these questions. The information in the report is confined to the activities of Federal and non-Federal agencies. It is based on information furnished to the Office of

Relative Influence of Initial Surface and Atmospheric Conditions on Seasonal Water and Energy Balances

NASA Technical Reports Server (NTRS)

Oglesby, Robert J.; Marshall, Susan; Roads, John O.; Robertson, Franklin R.; Goodman, H. Michael (Technical Monitor)

2001-01-01

We constructed and analyzed wet and dry soil moisture composites for the mid-latitude GCIP region of the central US using long climate model simulations made with the NCAR CCM3 and reanalysis products from NCEP. Using the diagnostic composites as a guide, we have completed a series of predictability experiments in which we imposed soil water initial conditions in CCM3 for the GCIP region for June 1 from anomalously wet and dry years, with atmospheric initial conditions taken from June 1 of a year with 'near-normal' soil water, and initial soil water from the near-normal year and atmospheric initial conditions from the wet and dry years. Preliminary results indicate that the initial state of the atmosphere is more important than the initial state of soil water determining the subsequent late spring and summer evolution of sod water over the GCIP region. Surprisingly, neither the composites or the predictability experiments yielded a strong influence of soil moisture on the atmosphere. To explore this further, we have made runs with extreme dry soil moisture initial anomalies imposed over the GCIP region (the soil close to being completely dry). These runs did yield a very strong effect on the atmosphere that persisted for at least three months. We conclude that the magnitude of the initial soil moisture anomaly is crucial, at least in CCM3, and are currently investigating whether a threshold exists, below which little impact is seen. In a complementary study, we compared the impact of the initial condition of snow cover versus the initial atmospheric state over the western US (corresponding to the westward extension of the GAPP program follow-on to GCIP). In this case, the initial prescription of snow cover is far more important than the initial atmospheric state in determining the subsequent evolution of snow cover. We are currently working to understand the very different soil water and snow cover results.

Assessing the effect of marginal water use efficiency on water use of loblolly pine and sweetgum in ambient and elevated CO2 conditions

NASA Astrophysics Data System (ADS)

Kim, D.; Medvigy, D.; Xu, X.; Oren, R.; Ward, E. J.

2017-12-01

Stomata are the common pathways through which diffusion of CO2 and water vapor take place in a plant. Therefore, the responses of stomatal conductance to environmental conditions are important to quantify carbon assimilation and water use of plants. In stomatal optimality theory, plants may adjust the stomatal conductance to maximize carbon assimilation for a given water availability. The carbon cost for unit water loss, marginal water use efficiency (λ), depends on changes in atmospheric CO2 concentration and pre-dawn leaf water potential. The relationship can be described by λ with no water stress (λ0) and the sensitivity of λ to pre-dawn leaf water potential (β0), which may vary by plant functional type. Assessment of sensitivity of tree and canopy water use to those parameters and the estimation of the parameters for individual plant functional type or species are needed. We modeled tree water use of loblolly pine (Pinus taeda) and sweetgum (Liquidambar styraciflua) in ambient and elevated CO2 (+200 µmol mol-1) at the Duke Forest free-air CO2 enrichment (FACE) site with Ecosystem Demography model 2 (ED2), a demographic terrestrial biosphere model that scales up individual-level competition for light, water and nutrients to the ecosystem-level. Simulated sap flux density for different tree size classes and species was compared to observations. The sensitivity analysis with respect to the model's hydraulic parameters was performed. The initial results showed that the impacts of λ on tree water use were greater than other hydraulic traits in the model, such as vertical hydraulic conductivity and leaf and stem capacitance. With 10% increase in λ, modeled water flow from root to leaf decreased by 2.5 and 1.6% for P. taeda and by 7.9 and 5.1% for L. styraciflua in ambient and elevated CO2 conditions, respectively. Values of hydraulic traits (λ0 and β0) for P. taeda and L. styraciflua in ambient an elevated CO2 conditions were also suggested.

Photosynthetic Activity and Adaptation Capacities of Lichens and Cyanobacteria to Martian Surface Conditions

NASA Astrophysics Data System (ADS)

De Vera, Jean-Pierre; Schulze-Makuch, D.; Khan, A.; Lorek, A.; Koncz, A.; Stivaletta, N.; Möhlmann, D.; Spohn, T.

2012-05-01

We observed an increase in photosynthetic activity in the lichen Pleopsidium chlorophanum but a strong negative effect on the photosynthetic activity of endolithic cyanobacteria when subjected for 34 days to environmental stresses likely to be encountered in semi-protected habitats on the Martian surface. Stresses were simulated in a Mars Simulation Chamber (MSC) and included high UV fluxes, low temperatures, low water activity, high atmospheric CO2 concentrations, and an atmospheric pressure of about 6 mbar. P. chlorophanum is an extremophile: it lives in very cold, dry, high-altitude habitats which are Earth's best approximation of the Martian surface. Our lichen samples came from North Victoria Land in Antarctica whereas the investigated samples of cyanobacteria came from tropic regions in the Sahara. Three samples of each group of organisms were exposed uninterruptedly to simulated conditions (as above) of the naked, unprotected Martian surface for 34 days, receiving the full Martian solar spectrum (200 - 2500 nm) for a cumulative UV dose of 6343.6 kJm-2. For a second sample set - containing also three lichen thalli and three endolithic cyanobacteria communities - the cumulative (34-day) UV dose was reduced to 268.8 kJm-2, to reasonably simulate the amount the microorganisms might receive in (semi-) protected surface sites (e.g., fissures, cracks and micro-caves within rocks or permafrost soil). In the 'unprotected' experiment it was unclear if the lichen was still actively photosynthesizing but still clear that the cyanobacteria were affected. However, under 'protected site' conditions, the cyanobacteria had no clear photosynthetic response under and after simulated Martian conditions but the lichen not only survived and remained photosynthetically active, it even adapted physiologically by increasing its photosynthetic activity over 34 days. Comparison with other Mars simulation experiments on exposure platforms in space and in the laboratory with other

Land-subsidence and ground-water storage monitoring in the Tucson Active Management Area, Arizona

USGS Publications Warehouse

Pool, Don R.; Winster, Daniel; Cole, K.C.

2000-01-01

The Tucson Active Management Area (TAMA) comprises two basins--Tucson Basin and Avra Valley. The TAMA has been directed by Arizona ground-water law to attain an annual balance between groundwater withdrawals and recharge by the year 2025. This balance is defined by the statute as "safe yield." Current ground-water withdrawals exceed recharge, resulting in conditions of ground-water overdraft, which causes removal of water from ground-water storage and subsidence of the land surface. Depletion of storage and associated land subsidence will not be halted until all discharge from the system, both natural and human induced, is balanced by recharge. The amount of the ground-water overdraft has been difficult to estimate until recently because it could not be directly measured. Overdraft has been estimated using indirect water-budget methods that rely on uncertain estimates of recharge. As a result, the status of the ground-water budget could not be known with great certainty. Gravity methods offer a means to directly measure ground-water overdraft through measurement of changes in the gravitational field of the Earth that are caused by changes in the amount of water stored in the subsurface. Changes in vertical position also affect the measured gravity value and thus subsidence also must be monitored. The combination of periodic observations of gravity and vertical positions provide direct measures of changes in stored ground water and land subsidence.

Performance of a biological deoxygenation process for ships' ballast water treatment under very cold water conditions.

PubMed

de Lafontaine, Yves; Despatie, Simon-Pierre

2014-02-15

Water deoxygenation is listed among the promising on-board treatment technologies to treat ships' ballast waters to reduce the risk of species transfer. We assessed the performance of a yeast-based bioreactive deoxygenation process in very cold water (<2°C) and determined the potential toxicity of the residual treated waters. Experiments using two treatment levels (0.5% and 1% v/v) were conducted in large-volume (4.5m(3)) tanks over 19 days at mean temperature of 1.5°C. Time to hypoxia varied between 10.3 and 16 days, being slightly higher than the predicted time of 9.8 days from previous empirical relationships. Water deoxygenation was achieved when yeast density exceeded 5×10(5) viable cellsmL(-1) and variation in time to hypoxia was mainly explained by difference in yeast growth. There was no oxycline and no significant difference in yeast density over the 2-m deep water column. Results from six bioassays indicated weak toxic response of treated waters at the 1.0% level, but no potential toxic response at the 0.5% treatment level. Results confirmed that the potential application of a yeast-based deoxygenation process for treating ships' ballast waters extended over the range of water temperature typically encountered during most shipping operational conditions. Time to reach full deoxygenation may however be limiting for universal application of this treatment which should be preferably used for ships making longer voyages in cold environments. There was no evidence that biological deoxygenation at low temperature did increase toxicity risk of treated waters to impede their disposal at the time of discharge. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

Extremophilic fungi in arctic ice: a relationship between adaptation to low temperature and water activity

NASA Astrophysics Data System (ADS)

Gunde-Cimerman, N.; Sonjak, S.; Zalar, P.; Frisvad, J. C.; Diderichsen, B.; Plemenitaš, A.

Little is known about fungal diversity in extremely cold regions. Low temperatures induce the formation of ice crystals and therefore also the creation of low water activity ( aw). These are the dominant factors in external chemistry that influence microbial biota in cold regions. Therefore, we have used selective low water activity media plus low incubation temperatures for the isolation of fungi from an Arctic environment. In comparison with the highest values of colony forming units (CFU) obtained on mesophilic media, considerably higher fungal CFU per litre of water were detected on low aw media, ranging from 1000 to 3000 l -1 in seawater, 6000 to 7000 l -1 in melted sea ice and up to 13,000 l -1 in melted glacier ice. The dominant taxa were ascomycetous and basidiomycetous yeasts, melanized fungi, mainly represented by the genera Cladosporium and Aureobasidium plus different species of the genus Penicillium. Preliminary taxonomic analyses revealed several new species and varieties. Further characterisations are needed to determine whether this diversity is due to geographic isolation, ecological conditions or independent evolutionary origin.

Plant osmoregulation as an emergent water-saving adaptation under salt-stress conditions

NASA Astrophysics Data System (ADS)

Perri, S.; Entekhabi, D.; Molini, A.

2017-12-01

Ecohydrological models have been widely used in studying plant-environment relations and hydraulic traits in response to water, light and nutrient limitations. In this context, models become a tool to investigate how plants exploit available resources to maximize transpiration and growth, eventually pointing out possible pathways to adaptation. In contrast, ecohydrologists have rarely focused on the effects of salinity on plant transpiration, which are commonly considered marginal in terrestrial biomes. The effect of salinity, however, cannot be neglected in the case of salt affected soils - estimated to cover over 9 billion ha worldwide - and in intertidal and coastal ecosystems. The objective of this study is to model the effects of salinity on plant-water relations in order to better understand the interplay of soil hyperosmotic conditions and osmoregulation strategies in determining different transpiration patterns. Salinity reduces the water potential, therefore is expected to affect the plant hydraulics and reduce plant conductance (eventually leading to cavitation for very high salt concentrations). Also, plant adaptation to short and long-term exposure to salinity comes into place to maintain an efficient water and nutrients uptake. We introduce a parsimonious soil-plant-atmosphere continuum (SPAC) model that incorporates parameterizations for morphological, physiological and biochemical mechanisms involving varying salt concentrations in the soil water solution. Transpiration is expressed as a function of soil water salinity and salt-mediated water flows within the SPAC (the conceptual representation of the model is shown in Figure c). The model is used to explain a paradox observed in salt-tolerant plants where maximum transpiration occurs at an intermediate value of salinity (CTr,max), and is lower in more fresh (CTr,max) and more saline (C>CTr,max) conditions (Figure a and b). In particular, we show that - in salt-tolerant species - osmoregulation

Non-destructive estimates of soil carbonic anhydrase activity and associated soil water oxygen isotope composition

NASA Astrophysics Data System (ADS)

Jones, Sam P.; Ogée, Jérôme; Sauze, Joana; Wohl, Steven; Saavedra, Noelia; Fernández-Prado, Noelia; Maire, Juliette; Launois, Thomas; Bosc, Alexandre; Wingate, Lisa

2017-12-01

The contribution of photosynthesis and soil respiration to net land-atmosphere carbon dioxide (CO2) exchange can be estimated based on the differential influence of leaves and soils on budgets of the oxygen isotope composition (δ18O) of atmospheric CO2. To do so, the activity of carbonic anhydrases (CAs), a group of enzymes that catalyse the hydration of CO2 in soils and plants, needs to be understood. Measurements of soil CA activity typically involve the inversion of models describing the δ18O of CO2 fluxes to solve for the apparent, potentially catalysed, rate of CO2 hydration. This requires information about the δ18O of CO2 in isotopic equilibrium with soil water, typically obtained from destructive, depth-resolved sampling and extraction of soil water. In doing so, an assumption is made about the soil water pool that CO2 interacts with, which may bias estimates of CA activity if incorrect. Furthermore, this can represent a significant challenge in data collection given the potential for spatial and temporal variability in the δ18O of soil water and limited a priori information with respect to the appropriate sampling resolution and depth. We investigated whether we could circumvent this requirement by inferring the rate of CO2 hydration and the δ18O of soil water from the relationship between the δ18O of CO2 fluxes and the δ18O of CO2 at the soil surface measured at different ambient CO2 conditions. This approach was tested through laboratory incubations of air-dried soils that were re-wetted with three waters of different δ18O. Gas exchange measurements were made on these soils to estimate the rate of hydration and the δ18O of soil water, followed by soil water extraction to allow for comparison. Estimated rates of CO2 hydration were 6.8-14.6 times greater than the theoretical uncatalysed rate of hydration, indicating that CA were active in these soils. Importantly, these estimates were not significantly different among water treatments, suggesting

Army Corps of Engineers: Water Resource Authorizations, Appropriations, and Activities

DTIC Science & Technology

2016-02-09

favorable benefit -cost ratio. 31 Local sponsors assume any rehabilitation cost for damage to an active project attributable to deficient maintenance...infrastructure activities are not traditional Corps water resources projects, they are not subject to the Corps planning process (e.g., a benefit -cost...Army Corps of Engineers: Water Resource Authorizations, Appropriations, and Activities Nicole T. Carter Specialist in Natural Resources Policy

A Curriculum Activities Guide to Water Pollution and Environmental Studies, Volume I - Activities.

ERIC Educational Resources Information Center

Hershey, John T., Ed.; And Others

This publication, Volume I of a two volume set, consists of many tested water pollution study activities. The activities are grouped into four headings: (1) Hydrologic Cycle, (2) Human Activities, (3) Ecological Perspectives, and (4) Social and Political Factors. Three levels of activities are provided: (1) those which increase awareness, (2)…

Plant response to environmental conditions: assessing potential production, water demand, and negative effects of water deficit

PubMed Central

Tardieu, François

2013-01-01

This paper reviews methods for analyzing plant performance and its genetic variability under a range of environmental conditions. Biomass accumulation is linked every day to available light in the photosynthetically active radiation (PAR) domain, multiplied by the proportion of light intercepted by plants and by the radiation use efficiency. Total biomass is cumulated over the duration of the considered phase (e.g., plant cycle or vegetative phase). These durations are essentially constant for a given genotype provided that time is corrected for temperature (thermal time). Several ways of expressing thermal time are reviewed. Two alternative equations are presented, based either on the effect of transpiration, or on yield components. Their comparative interests and drawbacks are discussed. The genetic variability of each term of considered equations affects yield under water deficit, via mechanisms at different scales of plant organization and time. The effect of any physiological mechanism on yield of stressed plants acts via one of these terms, although the link is not always straightforward. Finally, I propose practical ways to compare the productivity of genotypes in field environments, and a “minimum dataset” of environmental data and traits that should be recorded for that. PMID:23423357

The effect of nitrogen availability and water conditions on competition between a facultative CAM plant and an invasive grass.

PubMed

Yu, Kailiang; D'Odorico, Paolo; Carr, David E; Personius, Ashden; Collins, Scott L

2017-10-01

Plants with crassulacean acid metabolism (CAM) are increasing their abundance in drylands worldwide. The drivers and mechanisms underlying the increased dominance of CAM plants and CAM expression (i.e., nocturnal carboxylation) in facultative CAM plants, however, remain poorly understood. We investigated how nutrient and water availability affected competition between Mesembryanthemum crystallinum (a model facultative CAM species) and the invasive C 3 grass Bromus mollis that co-occur in California's coastal grasslands. Specifically we investigated the extent to which water stress, nutrients, and competition affect nocturnal carboxylation in M. crystallinum . High nutrient and low water conditions favored M. crystallinum over B. mollis , in contrast to high water conditions. While low water conditions induced nocturnal carboxylation in 9-week-old individuals of M. crystallinum , in these low water treatments, a 66% reduction in nutrient applied over the entire experiment did not further enhance nocturnal carboxylation. In high water conditions M. crystallinum both alone and in association with B. mollis did not perform nocturnal carboxylation, regardless of the nutrient levels. Thus, nocturnal carboxylation in M. crystallinum was restricted by strong competition with B. mollis in high water conditions. This study provides empirical evidence of the competitive advantage of facultative CAM plants over grasses in drought conditions and of the restricted ability of M. crystallinum to use their photosynthetic plasticity (i.e., ability to switch to CAM behavior) to compete with grasses in well-watered conditions. We suggest that a high drought tolerance could explain the increased dominance of facultative CAM plants in a future environment with increased drought and nitrogen deposition, while the potential of facultative CAM plants such as M. crystallinum to expand to wet environments is expected to be limited.

The calculation of quality indices of the water heat carrier and estimation of the condition of water chemistry of drum boilers

NASA Astrophysics Data System (ADS)

Larin, B. M.; Larin, A. B.; Kozyulina, E. V.; Kolegov, A. V.

2012-07-01

There is suggested a method for an indirect calculated identification of ionic impurities in water of drum boilers ( p b = 13.8 MPa) by means of measuring the electric conductivity of cooled samples (direct and H-cationized ones) of the feedwater and drum water. This paper reports the results of an industrial experiment carried out on the drum power boiler during the entire heating season. The possibility of evaluating the condition of the water chemistry, with plotting a phase diagram of the phosphate-based water chemistry and determining characteristic dependences, is shown.

7 CFR 612.2 - Snow survey and water supply forecast activities.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 6 2014-01-01 2014-01-01 false Snow survey and water supply forecast activities. 612... SUPPLY FORECASTS § 612.2 Snow survey and water supply forecast activities. To carry out the cooperative snow survey and water supply forecast program, NRCS: (a) Establishes, maintains, and operates manual...

7 CFR 612.2 - Snow survey and water supply forecast activities.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 6 2013-01-01 2013-01-01 false Snow survey and water supply forecast activities. 612... SUPPLY FORECASTS § 612.2 Snow survey and water supply forecast activities. To carry out the cooperative snow survey and water supply forecast program, NRCS: (a) Establishes, maintains, and operates manual...

7 CFR 612.2 - Snow survey and water supply forecast activities.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 6 2011-01-01 2011-01-01 false Snow survey and water supply forecast activities. 612... SUPPLY FORECASTS § 612.2 Snow survey and water supply forecast activities. To carry out the cooperative snow survey and water supply forecast program, NRCS: (a) Establishes, maintains, and operates manual...

7 CFR 612.2 - Snow survey and water supply forecast activities.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 6 2012-01-01 2012-01-01 false Snow survey and water supply forecast activities. 612... SUPPLY FORECASTS § 612.2 Snow survey and water supply forecast activities. To carry out the cooperative snow survey and water supply forecast program, NRCS: (a) Establishes, maintains, and operates manual...

7 CFR 612.2 - Snow survey and water supply forecast activities.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 6 2010-01-01 2010-01-01 false Snow survey and water supply forecast activities. 612... SUPPLY FORECASTS § 612.2 Snow survey and water supply forecast activities. To carry out the cooperative snow survey and water supply forecast program, NRCS: (a) Establishes, maintains, and operates manual...

Separation of Active Compounds from Food by-Product (Cocoa Shell) Using Subcritical Water Extraction.

PubMed

Jokić, Stela; Gagić, Tanja; Knez, Željko; Šubarić, Drago; Škerget, Mojca

2018-06-11

Large amounts of residues are produced in the food industries. The waste shells from cocoa processing are usually burnt for fuel or used as a mulch in gardens to add nutrients to soil and to suppress weeds. The objectives of this work were: (a) to separate valuable compounds from cocoa shell by applying sustainable green separation process—subcritical water extraction (SWE); (b) identification and quantification of active compounds, sugars and sugar degradation products in obtained extracts using HPLC; (c) characterization of the antioxidant activity of extracts; (d) optimization of separation process using response surface methodology (RSM). Depending on applied extraction conditions, different concentration of theobromine, caffeine, theophylline, epicatechin, catechin, chlorogenic acid and gallic acid were determined in the extracts obtained by subcritical water. Furthermore, mannose, glucose, xylose, arabinose, rhamnose and fucose were detected as well as their important degradation products such as 5-hydroxymethylfurfural (5-HMF), furfural, levulinic acid, lactic acid and formic acid.

Contribution to the Chemistry of Plasma-Activated Water

NASA Astrophysics Data System (ADS)

Julák, J.; Hujacová, A.; Scholtz, V.; Khun, J.; Holada, K.

2018-01-01

Plasma-activated water (PAW) was prepared by exposure to nonthermal plasma produced by a positive dc corona discharge in a transient spark regime. The activation of water was performed in atmosphere of various surrounding gases (air, nitrogen, carbon dioxide, and argon). This PAW retains its biological activity, measured on the mouse neuroblastoma cells culture, even after storage for more than one year. The highest hydrogen peroxide content was found for PAWs prepared in the atmospheres of argon or carbon dioxide, whereas the PAWs prepared in air and nitrogen exhibited lower hydrogen peroxide content. The acidity of PAWs mediated by nitric and nitrous acid formation displayed an opposite trend. It is concluded that the long-lasting biological effect of PAW is mediated by hydrogen peroxide in acid milieu only, whereas other possible active components decompose rapidly.

Nitrate Water Activities, Science Study Aid No. 4.

ERIC Educational Resources Information Center

Agricultural Research Service (USDA), Washington, DC.

Intended to supplement a regular program, this pamphlet provides background information, related activities, and suggestions for other activities on the subject of nitrate as a water pollutant. Two activities related to plant nutrient pollution, nitrate filtration and measuring mitrate used by plants, are explained in detail, outlining objectives,…

Annual summary of ground-water conditions in Arizona, spring 1979 to spring 1980

USGS Publications Warehouse

,

1981-01-01

Withdrawal of ground water, about 4.0 million acre-feet in Arizona in 1979, is about 200,000 acre-feet less than the amount withdrawn in 1978. The withdrawals in 1978 and 1979 are the smallest since the mid-1950 's except in 1966. Nearly all the decrease was in the amount of ground water used for irrigation in the Basin and Range lowlands province. The large amount of water in storage in the surface-water reservoirs, release of water from the reservoirs, floods, and conservation practices contributed to the decrease in ground-water use and caused water-level rises in the Salt River Valley, Gila Bend basin, and Gila River drainage from Painted Rock Dam to Texas Hill. Two small-scale maps show ground-water pumpage by areas and the status of the ground-water inventory in the State. The main map, which is at a scale of 1:500,000, shows potential well production, depth to water in selected wells in spring 1980, and change in water level in selected wells from 1975 to 1980. A brief text summarizes the current ground-water conditions in the State. (USGS)

SNAKE AND CLEARWATER RIVERS, PRESENT AND POST-IMPOUNDMENT WATER QUALITY CONDITIONS, 1964

EPA Science Inventory

This report presents information on present water quality conditions in the Snake and Clearwater Rivers (17060107, 17060103, 17060306) in the vicinity of Lewiston, Idaho and Clarkston, Washington. It discusses how changes in the streams characteristics resulting from the constru...

36 CFR 1002.63 - Boating and water use activities.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Boating and water use..., PUBLIC USE AND RECREATION § 1002.63 Boating and water use activities. Swimming, boating and the use of any water vessel are prohibited within the area administered by the Presidio Trust. ...

Time-resolved observation of thermally activated rupture of a capillary-condensed water nanobridge

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bak, Wan; Sung, Baekman; Kim, Jongwoo

2015-01-05

The capillary-condensed liquid bridge is one of the most ubiquitous forms of liquid in nature and contributes significantly to adhesion and friction of biological molecules as well as microscopic objects. Despite its important role in nanoscience and technology, the rupture process of the bridge is not well understood and needs more experimental works. Here, we report real-time observation of rupture of a capillary-condensed water nanobridge in ambient condition. During slow and stepwise stretch of the nanobridge, we measured the activation time for rupture, or the latency time required for the bridge breakup. By statistical analysis of the time-resolved distribution ofmore » activation time, we show that rupture is a thermally activated stochastic process and follows the Poisson statistics. In particular, from the Arrhenius law that the rupture rate satisfies, we estimate the position-dependent activation energies for the capillary-bridge rupture.« less

Design of Conditionally Active STATs: Insights into STAT Activation and Gene Regulatory Function

PubMed Central

Milocco, Lawrence H.; Haslam, Jennifer A.; Rosen, Jonathan; Seidel, H. Martin

1999-01-01

The STAT (signal transducer and activator of transcription) signaling pathway is activated by a large number of cytokines and growth factors. We sought to design a conditionally active STAT that could not only provide insight into basic questions about STAT function but also serve as a powerful tool to determine the precise biological role of STATs. To this end, we have developed a conditionally active STAT by fusing STATs with the ligand-binding domain of the estrogen receptor (ER). We have demonstrated that the resulting STAT-ER chimeras are estrogen-inducible transcription factors that retain the functional and biochemical characteristics of the cognate wild-type STATs. In addition, these tools have allowed us to evaluate separately the contribution of tyrosine phosphorylation and dimerization to STAT function. We have for the first time provided experimental data supporting the model that the only apparent role of STAT tyrosine phosphorylation is to drive dimerization, as dimerization alone is sufficient to unmask a latent STAT nuclear localization sequence and induce nuclear translocation, sequence-specific DNA binding, and transcriptional activity. PMID:10082558

Monochloramine cometabolism by Nitrosomonas europaea under drinking water conditions.

PubMed

Maestre, Juan P; Wahman, David G; Speitel, Gerald E

2013-09-01

Chloramine is widely used in United States drinking water systems as a secondary disinfectant, which may promote the growth of nitrifying bacteria because ammonia is present. At the onset of nitrification, both nitrifying bacteria and their products exert a monochloramine demand, decreasing the residual disinfectant concentration in water distribution systems. This work investigated another potentially significant mechanism for residual disinfectant loss: monochloramine cometabolism by ammonia-oxidizing bacteria (AOB). Monochloramine cometabolism was studied with the pure culture AOB Nitrosomonas europaea (ATCC 19718) in batch kinetic experiments under drinking water conditions. Three batch reactors were used in each experiment: a positive control to estimate the ammonia kinetic parameters, a negative control to account for abiotic reactions, and a cometabolism reactor to estimate the cometabolism kinetic constants. Kinetic parameters were estimated in AQUASIM with a simultaneous fit to all experimental data. The cometabolism reactors showed a more rapid monochloramine decay than in the negative controls, demonstrating that cometabolism occurs. Cometabolism kinetics were best described by a pseudo first order model with a reductant term to account for ammonia availability. Monochloramine cometabolism kinetics were similar to those of ammonia metabolism, and monochloramine cometabolism was a significant loss mechanism (30-60% of the observed monochloramine decay). These results suggest that monochloramine cometabolism should occur in practice and may be a significant contribution to monochloramine decay during nitrification episodes in drinking water distribution systems. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of water on olivine single crystal plasticity, deformed under upper mantle condition

NASA Astrophysics Data System (ADS)

Girard, J.; Chen, J.; Raterron, P. C.; Holyoke, C. W.

2011-12-01

The earth upper mantle, mainly composed of olivine, is seismically anisotropic. Seismic anisotropy attenuation has been observed at 200km depth. Karato et al. (1992) attributed this attenuation to a transition between two deformation mechanisms, from dislocation creep above 200km to diffusion creep bellow 200km. This transition occurs because of hydroxyl concentration. Mainprice et al.(2005) predicted a change in LPO induced by a change of slip system, from [100] slip to [001] slip, though theoritical modeling. According to his study, pressure is the parameter inducing the slip system transition, which is responsible for the seismic anisotropy attenuation. Raterron et al. (2007) performed single crystal deformation experiment under anhydrous conditions and observe that slip system transition occurring around 8 GPa. However this pressure would correspond to 300km depth which doesn't match the seismic anisotropy attenuation depth, observed by seismologist. In this study, experiments have been performed to quantify the effects of water on olivine single crystals deformed using Deformation DIA press and synchrotron beam. Deformation was carried out in uniaxial compression along the so-called [110]c and [011]c crystallographic direction in order to activate [100](010) and [001](010) dislocation slip system respectively, at P ranging from 4 to 8GPa and T=1200°C. Both single crystals were loaded in the cell to directly compare their deformation in same condition of stress temperature and pressure. We used a sleeve (talc = enstatite + coesite + H2O) about the annulus of the single crystals as source of water in the assembly. Stress and specimen strain rates were calculated by in-situ X-ray diffraction and time resolved imaging, respectively. By direct comparison of single crystals strain rates, we observed that [110]c deform faster than [011]c bellow 5GPa. However above 6GPa [011]c deform faster. This revealed that [100](010) is the dominant slip system bellow 5GPa, and

Removal of bromide and iodide anions from drinking water by silver-activated carbon aerogels.

PubMed

Sánchez-Polo, M; Rivera-Utrilla, J; Salhi, E; von Gunten, U

2006-08-01

The aim of this study is to analyze the use of Ag-doped activated carbon aerogels for bromide and iodide removal from drinking water and to study how the activation of Ag-doped aerogels affects their behavior. It has been observed that the carbonization treatment and activation process of Ag-doped aerogels increased the surface area value ( [Formula: see text] ), whereas the volume of meso-(V(2)) and macropores (V(3)) decreased slightly. Chemical characterization of the materials revealed that carbonization and especially activation process considerably increased the surface basicity of the sample. Original sample (A) presented acidic surface properties (pH(PZC)=4.5) with 21% surface oxygen, whereas the sample that underwent activation showed mainly basic surface chemical properties (pH(PZC)=9.5) with only 6% of surface oxygen. Carbonization and especially, activation process considerable increased the adsorption capacity of bromide and iodide ions. This would mainly be produced by (i) an increase in the microporosity of the sample, which increases Ag-adsorption sites available to halide anions, and (ii) a rise of the basicity of the sample, which produces an increase in attractive electrostatic interactions between the aerogel surface, positively charged at the working pH (pH(solution)water treatment, adsorption of bromide and iodide was studied under dynamic conditions using waters from Lake Zurich. Results obtained showed that the carbonization and activation processes increased the adsorptive capacity of the aerogel sample. However, results showed that the adsorption capacity of the aerogel samples studied was considerably lower in water from Lake Zurich. Results showed X(0.02) (amount adsorbed to initial breakthrough) values of 0.1 and 4.3 mg/g for chloride anion and dissolved organic carbon (DOC), respectively, during bromide adsorption process in water from Lake Zurich

Changes in seed water status as characterized by NMR in developing soybean seed grown under moisture stress conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krishnan, P., E-mail: pkrishnan@iari.res.in; Singh, Ravender; Verma, A.P.S.

Highlights: • In developing soybean seeds, moisture stress resulted in more proportion of water to bound state. • These changes are further corroborated by concomitant changes in seed metabolites. • Thus there exists a moisture stress and development stage dependence of seed tissue water status. - Abstract: Changes in water status of developing seeds of Soybean (Glycine max L. Merrill.) grown under different moisture stress conditions were characterized by proton nuclear magnetic resonance (NMR)- spin–spin relaxation time (T{sub 2}). A comparison of the seed development characteristics, composition and physical properties indicated that, characteristics like seed weight, seed number/ear, rate ofmore » seed filling increased with development stages but decreased with moisture stress conditions. The NMR- spin–spin relaxation (T{sub 2}) component like bound water increased with seed maturation (40–50%) but decreased with moisture stress conditions (30–40%). The changes in seed water status to increasing levels of moisture stress and seed maturity indicates that moisture stress resulted in more proportion of water to bound state and intermediate state and less proportion of water in free-state. These changes are further corroborated by significant changes in protein and starch contents in seeds under high moisture stress treatments. Thus seed water status during its development is not only affected by development processes but also by moisture stress conditions. This study strongly indicated a clear moisture stress and development stage dependence of seed tissue water status in developing soybean seeds.« less