Lipoproteins during the estrous cycle in swine.

PubMed

Liu, Ying; Rector, R Scott; Thomas, Tom R; Taylor, Julia A; Holiman, Denise A; Henderson, Kyle K; Welshons, Wade V; Sturek, Michael S

2004-02-01

The purpose of this study was to examine lipoprotein values at high versus low 17beta-estradiol (E2) concentrations in Yucatan miniature swine. Estrous cycles were measured by heat checking the female on a daily basis using a boar. All swine were fed a 1,050-g low-fat, standard chow diet (8% kcal from fat) once per day. Fasted (24 hours) blood samples were collected during low (early luteal, day 5) and high (late follicular, day 18) E2 concentrations to determine differences in concentrations of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL-C), high-density lipoprotein cholesterol (HDL-C), and subfractions. Concentrations of E2 differed significantly from day 5 (3.5 +/- 0.7 pg/mL) to day 18 (14.2 +/- 1.8 pg/mL) of the estrous cycle. Except for HDL(3)-C, all lipoprotein parameters examined were significantly elevated during high E2 versus low E2. TC/HDL-C and LDL-C/HDL-C ratios were significantly lower during the high E2 phase. These results suggest that lipoprotein concentrations fluctuate during the estrous cycle of swine, with high E2 concentrations associated with elevated lipoprotein concentrations.

Geochemical aspects of some Japanese lavas.

NASA Technical Reports Server (NTRS)

Philpotts, J. A.; Martin, W.; Schnetzler, C. C.

1971-01-01

K, Rb, Sr, Ba and rare-earth concentrations in some Japanese lavas have been determined by mass-spectrometric stable-isotope dilution. The samples fall into three rare-earth groups corresponding to tholeiitic, high alumina and alkali basalts. Japanese tholeiites have trace element characteristics similar to those of oceanic ridge tholeiites except for distinctly higher relative concentrations of Ba. Japanese lavas may result from various degrees of partial fusion of amphibole eclogite.

Anomalous bioaccumulation of lead in the earthworm Eisenoides lonnbergi (Michaelsen)

USGS Publications Warehouse

Beyer, W. Nelson; Codling, Eton E.; Rutzke, Michael A.

2018-01-01

Lead concentrations in soil organisms are usually well below those in the associated soil and tend to decrease with each higher trophic level in a food chain. Earthworms of the species Eisenoides lonnbergi provide an exception to this observation, accumulating very high concentrations of lead from acidic soils. Earthworms belonging to this species were collected from strongly to extremely acidic soils at 16 sites on a wildlife refuge in Maryland, USA. A lead concentration as high as 766 mg/kg, dry weight, was detected in depurated E. lonnbergi collected from soil containing only 17 mg/kg of lead. Concentration factors (ratio of lead concentration in earthworms to lead concentration in soil, dry wt) were highly variable at the sites, from 1.0 to 83. As suggested previously, lead absorption by earthworms is enhanced in low-calcium soils. The anomalously high concentrations of lead found in E. lonnbergi are more closely correlated with the uptake of calcium from acidic soils than with bioaccessibility of soil lead. 

Accumulation of heavy metals in soil and their transfer to leafy vegetables in the region of Dhaka Aricha Highway, Savar, Bangladesh.

PubMed

Aktaruzzaman, M; Fakhruddin, A N M; Chowdhury, M A Z; Fardous, Z; Alam, M K

2013-04-01

Accumulation of heavy metals in environmental matrices is a potential risk to living system due to their uptake by plants and subsequent introduction into the food chain. A study was conducted to investigate the heavy metals concentration in soils and leafy vegetables samples along the Dhaka Aricha Road to assess their potential ecological risk. Heavy metals concentration was analyzed by Atomic Absorption Spectroscopy. Concentrations ofallthetestedheavy metals except Cd in soil samples were below the permissible level. The mean concentration of Cd was found 3.99 +/- 1.85 mg kg(-1). Concentrations of all the tested heavy metals except Cd and Cr in vegetables samples were lower than recommended level. Mean concentration of Cd and Cr were found 1.00 +/- 0.68 mg kg(-1) and 2.32 +/- 0.84 mg kg(-1), respectively. Based on the Potential Ecological Risk Index, Cd posed very high risk to the local ecosystem due to its higher Risk Factor, > 320 and based on Transfer Factor of Pb and Cd were found higher accumulator among the tested metals. The results of present study revealed that the bioconcentration of heavy metals along the Dhaka Aricha Road posed high risk to the ecosystem. Considering the Transfer Factor of Cd and Pb it can be suggested that plants and leafy vegetables grow in the soil near Dhaka Aricha Road should not be used as food or feed.

Distribution patterns of mercury in Lakes and Rivers of northeastern North America

USGS Publications Warehouse

Dennis, Ian F.; Clair, Thomas A.; Driscoll, Charles T.; Kamman, Neil; Chalmers, Ann T.; Shanley, Jamie; Norton, Stephen A.; Kahl, Steve

2005-01-01

We assembled 831 data points for total mercury (Hgt) and 277 overlapping points for methyl mercury (CH3Hg+) in surface waters from Massachussetts, USA to the Island of Newfoundland, Canada from State, Provincial, and Federal government databases. These geographically indexed values were used to determine: (a) if large-scale spatial distribution patterns existed and (b) whether there were significant relationships between the two main forms of aquatic Hg as well as with total organic carbon (TOC), a well know complexer of metals. We analyzed the catchments where samples were collected using a Geographical Information System (GIS) approach, calculating catchment sizes, mean slope, and mean wetness index. Our results show two main spatial distribution patterns. We detected loci of high Hgt values near urbanized regions of Boston MA and Portland ME. However, except for one unexplained exception, the highest Hgt and CH3Hg+ concentrations were located in regions far from obvious point sources. These correlated to topographically flat (and thus wet) areas that we relate to wetland abundances. We show that aquatic Hgt and CH3Hg+ concentrations are generally well correlated with TOC and with each other. Over the region, CH3Hg+ concentrations are typically approximately 15% of Hgt. There is an exception in the Boston region where CH3Hg+ is low compared to the high Hgt values. This is probably due to the proximity of point sources of inorganic Hg and a lack of wetlands. We also attempted to predict Hg concentrations in water with statistical models using catchment features as variables. We were only able to produce statistically significant predictive models in some parts of regions due to the lack of suitable digital information, and because data ranges in some regions were too narrow for meaningful regression analyses.

40 CFR 50.14 - Treatment of air quality monitoring data influenced by exceptional events.

Code of Federal Regulations, 2010 CFR

2010-07-01

... specific air pollution concentration at a particular air quality monitoring location. (2) Demonstration to... exceptional event caused a specific air pollution concentration in excess of one or more national ambient air... specific air pollution concentration in excess of one or more national ambient air quality standards at a...

Urinary concentrations of environmental phenols in pregnant women in a pilot study of the National Children's Study

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

Mortensen, Mary E., E-mail: MMortensen@cdc.gov; Calafat, Antonia M.; Ye, Xiaoyun

Environmental phenols are a group of chemicals with widespread uses in consumer and personal care products, food and beverage processing, and in pesticides. We assessed exposure to benzophenone-3, bisphenol A (BPA), triclosan, methyl- and propyl parabens, and 2,4- and 2,5-dichlorophenol or their precursors in 506 pregnant women enrolled in the National Children's Study (NCS) Vanguard Study. We measured the urinary concentrations of the target phenols by using online solid-phase extraction–isotope dilution high performance liquid chromatography–tandem mass spectrometry. NCS women results were compared to those of 524 similar-aged women in the National Health and Nutrition Examination Survey (NHANES) 2009–2010, and tomore » 174 pregnant women in NHANES 2005–2010. In the NCS women, we found significant racial/ethnic differences (p<0.05) in regression adjusted mean concentrations of benzophenone-3, triclosan, 2,4- and 2,5-dichlorophenol, but not of BPA. Urinary 2,4- and 2,5-dichlorophenol concentrations were highly correlated (r=0.66, p<0.0001). Except for BPA and triclosan, adjusted mean concentrations were significantly different across the 7 study sites. Education was marginally significant for benzophenone-3, triclosan, propyl paraben, and 2,5-dichlorophenol. Urinary concentrations of target phenols in NCS pregnant women and U.S. women and pregnant women were similar. In NCS pregnant women, race/ethnicity and geographic location determined urinary concentrations of most phenols (except BPA), suggesting differential exposures. NCS Main Study protocols should collect urine biospecimens and information about exposures to environmental phenols. - Highlights: • Limited biomonitoring data are available in pregnant women. • Seven urinary phenols were measured in 506 third trimester women enrolled in the NCS. • Urine benzophenone-3, triclosan, 2,4- and 2,5-dichlorophenol differed by race/ethnicity. • Urinary concentrations of 2,4- and 2,5-dichlorophenol were highly correlated. • Exposure information can expand the utility of biospecimens in the NCS Main Study.« less

Development of an ultra-high-pressure liquid chromatography-tandem mass spectrometry multi-residue sulfonamide method and its application to water, manure slurry, and soils from swine rearing facilities.

PubMed

Shelver, Weilin L; Hakk, Heldur; Larsen, Gerald L; DeSutter, Thomas M; Casey, Francis X M

2010-02-19

An analytical method was developed using ultra-high-pressure liquid chromatography-triple quadrupole-tandem mass spectrometry (UHPLC-TQ-MS/MS) to simultaneously analyze 14 sulfonamides (SA) in 6 min. Despite the rapidity of the assay the system was properly re-equilibrated in this time. No carryover was observed even after high analyte concentrations. The instrumental detection limit based on signal-to-noise ratio (S/N)>3, was below 1 pg/microL (5 pg on column) for all SAs except sulfachloropyridazine. Surface water, ground water, soil, and slurry manure contained in storage ponds in and around swine [Sus scrofa domesticus] rearing facilities were analyzed. Sample cleanup for ground water and surface water included using solid phase extraction (SPE) using Oasis hydrophilic-lipophilic balance (HLB) cartridges. The soil and slurry manure required tandem strong anion exchange (SAX) and HLB solid phase extraction cartridges for sample cleanup. With few exceptions, the recoveries ranged from 60 to 100% for all matrices. The minimum detectable levels were below 2.0 ng/L for water, 30 ng/L for slurry manure, and 45 ng/kg for soil except for sulfachloropyridazine. The coefficient of variation (CV) was within 20% for most of the compounds analyzed. Using this method, sulfamethazine concentrations of 2250-5060 ng/L, sulfamethoxazole concentrations of 108-1.47 x 10(6)ng/L, and sulfathiazole concentrations of 785-1700 ng/L were found in the slurry manure. Sulfadimethoxine (2.0-32 ng/L), sulfamethazine (2.0-5.1 ng/L), and sulfamethoxazole (20.5-43.0 ng/L) were found in surface water and ground water. In top soil (0-15 cm), sulfamethazine ranged 34.5-663 ng/kg dry weight in those locations that received slurry manure as a nutrient; no SAs were found in the soil depths between 46 and 61 cm. The speed makes the method practical for medium to high throughput applications. The sensitivity and positive analyte identification make the method suitable for the demanding requirements for real world applications. Published by Elsevier B.V.

46 CFR 197.535 - Regulated areas.

Code of Federal Regulations, 2011 CFR

2011-10-01

... GENERAL PROVISIONS Benzene § 197.535 Regulated areas. (a) Based on the employer's evaluation of the environmental monitoring, whenever the airborne concentration of benzene within an area exceeds or reasonably... inches high (except for the words “DANGER—BENZENE”, which must be printed in letters at least 50 percent...

46 CFR 197.535 - Regulated areas.

Code of Federal Regulations, 2010 CFR

2010-10-01

... GENERAL PROVISIONS Benzene § 197.535 Regulated areas. (a) Based on the employer's evaluation of the environmental monitoring, whenever the airborne concentration of benzene within an area exceeds or reasonably... inches high (except for the words “DANGER—BENZENE”, which must be printed in letters at least 50 percent...

46 CFR 197.535 - Regulated areas.

Code of Federal Regulations, 2012 CFR

2012-10-01

... GENERAL PROVISIONS Benzene § 197.535 Regulated areas. (a) Based on the employer's evaluation of the environmental monitoring, whenever the airborne concentration of benzene within an area exceeds or reasonably... inches high (except for the words “DANGER—BENZENE”, which must be printed in letters at least 50 percent...

46 CFR 197.535 - Regulated areas.

Code of Federal Regulations, 2014 CFR

2014-10-01

... GENERAL PROVISIONS Benzene § 197.535 Regulated areas. (a) Based on the employer's evaluation of the environmental monitoring, whenever the airborne concentration of benzene within an area exceeds or reasonably... inches high (except for the words “DANGER—BENZENE”, which must be printed in letters at least 50 percent...

46 CFR 197.535 - Regulated areas.

Code of Federal Regulations, 2013 CFR

2013-10-01

... GENERAL PROVISIONS Benzene § 197.535 Regulated areas. (a) Based on the employer's evaluation of the environmental monitoring, whenever the airborne concentration of benzene within an area exceeds or reasonably... inches high (except for the words “DANGER—BENZENE”, which must be printed in letters at least 50 percent...

Influence of population density on the concentration and speciation of metals in the soil and street dust from urban areas.

PubMed

Acosta, J A; Gabarrón, M; Faz, A; Martínez-Martínez, S; Zornoza, R; Arocena, J M

2015-09-01

Street dust and soil from high, medium and low populated cities and natural area were analysed for selected physical-chemical properties, total and chemical speciation of Zn, Pb, Cu, Cr, Cd, Co, Ni to understand the influence of human activities on metal accumulation and mobility in the environment. The pH, salinity, carbonates and organic carbon contents were similar between soil and dust from the same city. Population density increases dust/soil salinity but has no influence on metals concentrations in soils. Increases in metal concentrations with population density were observed in dusts. Cu, Zn, Pb, Cr can be mobilized more easily from dust compared to the soil. In addition, population density increase the percentage of Pb and Zn associated to reducible and carbonate phase in the dust. The behaviour of metals except Cd in soil is mainly affected by physico-chemical properties, while total metal influenced the speciation except Cr and Ni in dusts. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biomimetic nanocoatings with exceptional mechanical, barrier, and flame-retardant properties from large-scale one-step coassembly

PubMed Central

Ding, Fuchuan; Liu, Jingjing; Zeng, Songshan; Xia, Yan; Wells, Kacie M.; Nieh, Mu-Ping; Sun, Luyi

2017-01-01

Large-scale biomimetic organic/inorganic hybrid nanocoatings with a nacre-like microstructure were prepared via a facile coassembly process. Different from conventional polymer nanocomposites, these nanocoatings contain a high concentration of nanosheets, which can be well aligned along the substrate surface. Moreover, the nanosheets and polymer matrix can be chemically co–cross-linked. As a result, the nanocoatings exhibit exceptional mechanical properties (high stiffness and strength), barrier properties (to both oxygen and water vapor), and flame retardancy, but they are also highly transparent (maintaining more than 85% of their original transmittance to visible light). The nanocoatings can be applied to various substrates and regular or irregular surfaces (for example, films and foams). Because of their excellent performance and high versatility, these nanocoatings are expected to find widespread application. PMID:28776038

Groundwater Quality Assessment in the Upper East Region of Ghana

NASA Astrophysics Data System (ADS)

Apambire, W. B.

2001-05-01

In Ghana, West Africa, fluoride occurs as a natural pollutant in some groundwaters, while the presence of isolated high levels of nitrate and arsenic in groundwater is due to human activities such as poor sanitation, garbage disposal and mining practices. The challenge for Ghana is to ensure that groundwater quality and environmental adversities such as water level decline are not compromised by attempts to increase water quantity. Concentrations of groundwater fluoride in the study area range from 0.11 to 4.60 mg/L, with the highest concentrations found in the fluorine-enriched Bongo granitoids. Eighty-five out of 400 wells sampled have fluoride concentrations above the World Health Organization maximum guideline value of 1.5 mg/L and thus causes dental fluorosis in children drinking from the wells. The distribution of fluoride in groundwater is highly related to the distribution of dental fluorosis in the UER. Nitrate concentrations ranged from 0.03 to 211.00 mg/L and the mean value was 16.11 mg/L. Twenty-one samples had concentrations in excess of the guideline value of 45 mg/L. Consumption of water in excess of the guideline value, by infants, may cause an infantile disease known as methaemoglobinaemia. It is inferred that groundwaters with exceptionally high NO3 values have been contaminated principally through human activities such as farming and waste disposal. This is because wells with high nitrate concentrations are all located in and around towns and sizable villages. Also, there is good correlation between Cl and NO3 (r = +0.74), suggesting that both elements come from the same sources of pollution. Only two well waters had concentrations of iron in excess of the guideline value of 0.3 mg/L. These samples come from shallow hand-dug wells. The maximum concentration of iron in groundwaters is 3.5 mg/L. The recommended guideline limit for Al in drinking water is 0.2 mg/L; two wells had Al concentrations of 12.0 and 4.0 mg/L, respectively. Other high concentrations of Al are associated with shallow wells and ponds. There is a highly positive correlation (r = +1) between Fe and Al, suggesting that dissolution of weathered lateritic material (e.g., Fe oxides, gibbsite, etc.) is the common source for these elements. Manganese concentrations are generally within acceptable limits, except for 11 wells that have concentrations above the guideline limit of 0.1 mg/L. These anomalous concentrations may be associated with manganiferous deposits in the study area. A majority of the samples contain very low concentrations of the trace elements Zn, Pb, Cd, Cr, As and Se; however, the highest concentrations occur in areas where small-scale mining is practiced.

Effect of solutes in binary columbium /Nb/ alloys on creep strength

NASA Technical Reports Server (NTRS)

Klein, M. J.; Metcalfe, A. G.

1973-01-01

The effect of seven different solutes in binary columbium (Nb) alloys on creep strength was determined from 1400 to 3400 F for solute concentrations to 20 at.%, using a new method of creep-strength measurement. The technique permits rapid determination of approximate creep strength over a large temperature span. All of the elements were found to increase the creep strength of columbium except tantalum. This element did not strengthen columbium until the concentration exceeded 10 at.%. Hafnium, zirconium, and vanadium strengthed columbium most at low temperatures and concentrations, whereas tungsten, molybdenum, and rhenium contributed more to creep strength at high temperatures and concentrations.

Flexible Ferroelectric Sensors with Ultrahigh Pressure Sensitivity and Linear Response over Exceptionally Broad Pressure Range.

PubMed

Lee, Youngoh; Park, Jonghwa; Cho, Soowon; Shin, Young-Eun; Lee, Hochan; Kim, Jinyoung; Myoung, Jinyoung; Cho, Seungse; Kang, Saewon; Baig, Chunggi; Ko, Hyunhyub

2018-04-24

Flexible pressure sensors with a high sensitivity over a broad linear range can simplify wearable sensing systems without additional signal processing for the linear output, enabling device miniaturization and low power consumption. Here, we demonstrate a flexible ferroelectric sensor with ultrahigh pressure sensitivity and linear response over an exceptionally broad pressure range based on the material and structural design of ferroelectric composites with a multilayer interlocked microdome geometry. Due to the stress concentration between interlocked microdome arrays and increased contact area in the multilayer design, the flexible ferroelectric sensors could perceive static/dynamic pressure with high sensitivity (47.7 kPa -1 , 1.3 Pa minimum detection). In addition, efficient stress distribution between stacked multilayers enables linear sensing over exceptionally broad pressure range (0.0013-353 kPa) with fast response time (20 ms) and high reliability over 5000 repetitive cycles even at an extremely high pressure of 272 kPa. Our sensor can be used to monitor diverse stimuli from a low to a high pressure range including weak gas flow, acoustic sound, wrist pulse pressure, respiration, and foot pressure with a single device.

Measurements of formaldehyde and acetaldehyde in the urban ambient air

NASA Astrophysics Data System (ADS)

Salas, Louis J.; Singh, Hanwant B.

Acetaldehyde and formaldehyde were measured in urban ambient air by analyzing their 2,4-dinitrophenylhydrazine derivatives with reverse-phase, high-performance liquid chromatography (HPLC). A series of nine short term field experiments were performed in eight cities. Concurrent formaldehyde measurements using the chromotropic-acid procedure show reasonable agreement (±30 %) between the two methods. Average summertime ambient urban formaldehyde (HCHO) concentrations of 10-20 ppb (10 -9v/v) are significantly higher than the average acetaldehyde (CH 3CHO) concentrations of 1-2 ppb. There is evidence of much reduced formaldehyde levels in winter months. Exceptionally high, absolute (8.5 ppb av.) and relative ( HCHO/CH 3CHO ~ 2 ) acetaldehyde concentrations are measured in the South Coast Air Basin of California.

An Alternative to NOx Cap-and-Trade Programs: An Exploratory Analysis of Charging NOx Emitters for Health Damages

NASA Astrophysics Data System (ADS)

Mauzerall, D. L.; Sultan, B.; Kim, N.; Bradford, D.

2003-12-01

To address the problem of elevated O3 concentrations throughout the northeastern United States in summer, a NOx cap-and-trade program was implemented that reduced NOx emissions from large point sources by nearly 50%. To determine whether this program has been successful, we examine O3, NO and temperature measurements collected in the EPA-AIRS network prior to and after the cap-and-trade program went into effect in 1999. Ambient NO concentrations as measured in the EPA-AIRS network are lower in the post-cap period in all months except July. We find that the upper half of the distribution of O3 concentrations within the region is essentially unchanged (or slightly higher) in May and June, modestly reduced in July and August (except the highest concentrations which are larger in August), and significantly lower in September (ranging from 0-20 ppb lower between the mean and highest concentrations) in the 1999-2001 post-cap period relative to the 1995-1998 pre-cap period. Except for September, the frequency with which the 80ppb 8-hour NAAQS standard for O3 is exceeded has not decreased. Temperatures during the post-cap period were slightly higher in June, July and August, and slightly lower in September - likely contributing to reduced O3 levels during September in the post-cap period. To explore the possibility that trading, or selective emissions over the course of the summer, could influence regional O3 concentrations, we conduct chemical transport modeling experiments using the CAMx regional model. Even within May-September for a single year, demands for electrical power and hence NOx emissions are greater during hot than cool periods. We demonstrate that substantially more O3 is produced from identical NOx emissions from a single power plant on high temperature than on low temperature days in July 1995. Thus a lack of temporal restrictions on when in a single summer month NOx emissions may occur can result in higher O3 levels. We also demonstrate that identical NOx emissions in regions of high (low) isoprene emission result in greater (lesser) O3 production. This indicates that NOx trades from locations with low to high isoprene emissions likely result in increases in O3 production. Since the objective of reducing O3 concentrations is to reduce the impact elevated O3 has on human health and welfare, we examine the mortalities that result from the O3 produced from a fixed NOx emission in the two cases described above as well as in regions of high and low population. We estimate substantially higher mortality rates from a unit NOx emission as a result of elevated O3 concentrations for high temperature days, in regions of high isoprene emissions, and for emissions occurring upwind of large populations. We attempt to assign a monetary value to the loss of life resulting from the enhanced O3 concentrations that result from these NOx emissions. We propose, as an alternative to NOx emissions cap and trade programs, a system by which NOx emitters are charged for the marginal damage they cause as a result of the O3 produced from the NOx they emit. Rather than resulting in a reduction in total NOx emissions without necessarily reducing O3 concentrations (as a cap-and-trade program does), this alternative system provides a direct incentive to reduce NOx emissions at times and places where they cause the most harm.

Rationale behind the near-ideal catalysis of Candida antarctica lipase A (CAL-A) for highly concentrating ω-3 polyunsaturated fatty acids into monoacylglycerols.

PubMed

He, Yongjin; Li, Jingbo; Kodali, Sitharam; Chen, Bilian; Guo, Zheng

2017-03-15

Dramatic decline in the quality and quantity of ω-3 PUFAs from marine resource demands new environmental-friendly technology to produce high quality ω-3 PUFAs concentrates in a better bioavailable form. Accordingly this work demonstrated an exceptionally highly efficient non-aqueous approach that non-regiospecific and non ω-3 PUFAs preferential Candida antarctica lipase A (CAL-A), functioning as a near-ideal biocatalyst, is capable to directly concentrate ω-3 PUFAs from 20% to 30% in oils to up to >90% in monoacylglycerols form through one step reaction. The rationale behind the experimental observation is justified and the catalytic property and specificity of an ideal enzyme tackling this task are defined. High selectivity and efficiency, excellent reusability of biocatalyst, general applicability for concentrating ω-3 PUFAs from both fish and microalgae oils, simple process for product recovery (e.g. by short path distillation), make this novel approach a highly industrially relevant and with potential application in food and drug industries. Copyright © 2016 Elsevier Ltd. All rights reserved.

Parenting of Divorced Fathers and the Association with Children's Self-Esteem

ERIC Educational Resources Information Center

Bastaits, Kim; Ponnet, Koen; Mortelmans, Dimitri

2012-01-01

Research suggests that high parental support and control improves children's well-being. However, a large part of these studies have focused on the parenting of married parents. Research on parenting after a divorce, mainly has focused on parenting of divorced mothers, with few exceptions concentrating primarily on non-residential fathers.…

Ultrabreathable and protective membranes with sub-5 nm carbon nanotube pores

DOE PAGES

Bui, Ngoc; Meshot, Eric R.; Kim, Sangil; ...

2016-05-09

Here, small-diameter carbon nanotubes (CNTs) are shown to enable exceptionally fast transport of water vapor under a concentration gradient driving force. Thanks to this property, membranes having sub-5 nm CNTs as conductive pores feature outstanding breathability while maintaining a high degree of protection from biothreats by size exclusion.

Exceptionally omnidirectional broadband light harvesting scheme for multi-junction concentrator solar cells achieved via ZnO nanoneedles

NASA Astrophysics Data System (ADS)

Yeh, Li-Ko; Tian, Wei-Cheng; Lai, Kun-Yu; He-Hau, Jr.

2016-12-01

GaInP/GaAs/Ge triple-junction concentrator solar cells with significant efficiency enhancement were demonstrated with antireflective ZnO nanoneedles. The novel nanostructure was attained with a Zn(NO3)2-based solution containing vitamin C. Under one sun AM 1.5G solar spectrum, conversion efficiency of the triple-junction device was improved by 23.7% via broadband improvement in short-circuit currents of 3 sub-cells after the coverage by the nanoneedles with a graded refractive index profile. The efficiency enhancement further went up to 45.8% at 100 suns. The performance boost through the nanoneedles also became increasingly pronounced in the conditions of high incident angles and the cloudy weather, e.g. 220.0% of efficiency enhancement was observed at the incident angle of 60°. These results were attributed to the exceptional broadband omnidirectionality of the antireflective nanoneedles.

Determination of the absolute internal quantum efficiency of photoluminescence in GaN co-doped with Si and Zn

NASA Astrophysics Data System (ADS)

Reshchikov, M. A.; Foussekis, M.; McNamara, J. D.; Behrends, A.; Bakin, A.; Waag, A.

2012-04-01

The optical properties of high-quality GaN co-doped with silicon and zinc are investigated by using temperature-dependent continuous-wave and time-resolved photoluminescence measurements. The blue luminescence band is related to the ZnGa acceptor in GaN:Si,Zn, which exhibits an exceptionally high absolute internal quantum efficiency (IQE). An IQE above 90% was calculated for several samples having different concentrations of Zn. Accurate and reliable values of the IQE were obtained by using several approaches based on rate equations. The concentrations of the ZnGa acceptors and free electrons were also estimated from the photoluminescence measurements.

Quantitative analysis of antibiotics in aquifer sediments by liquid chromatography coupled to high resolution mass spectrometry.

PubMed

Tong, Lei; Liu, Hui; Xie, Cong; Li, Minjing

2016-06-24

A highly effective analytical method for multi-residue determination of antibiotics in aquifer sediments was first established in this study. Microwave-assisted solvent extraction (MASE) and solid-phase extraction were used for sample pre-concentration and purification, ultra-high performance liquid chromatography coupled to hybrid quadrupole-high resolution Orbitrap mass spectrometry (UHPLC-Q-Orbitrap) was applied for detection. For high resolution mass spectrometry (HRMS), the target compounds were tentatively identified by retention time and accurate mass which was measured with precursor ions in Target-SIM scan, and then confirmed by the monitoring of daughter ion fragments which were generated in dd-MS(2) scan. The results provided good mass accuracy with mass deviations below 2ppm (except norfloxacin with -2.3ppm) for quantitative analysis of the compounds by HRMS. Reasonable recoveries of all analytes were obtained more than 60% (except doxytetracycline) in fortification samples at concentrations higher than 10μgkg(-1). Relative standard deviations of repeatability and inter-day precision were below 21% and 11%. Limits of detection (LOD) ranged from 0.1 to 3.8μgkg(-1), whereas limits of quantification (LOQ) were established between 0.3-9.0μgkg(-1). The method was applied to analyze real aquifer sediment samples in different aquifer depth of 4.0, 7.5, 13.0 and 18.0m. Chlorotetracycline and ofloxacin were observed at relative high concentrations of 53 and 19μgkg(-1) respectively in 18.0m deepness. The exposure to low doses of these compounds in subsurface environment increases concerns on long-term ecological security of underground system. Copyright © 2016 Elsevier B.V. All rights reserved.

Fog water chemistry in the Namib desert, Namibia

NASA Astrophysics Data System (ADS)

Eckardt, Frank D.; Schemenauer, Robert S.

This study documents the ion concentrations and ion enrichment relative to sea water, in Namib Desert fog water, with the purpose of establishing its suitability for future fogwater collection schemes, while also examining claims that Namib Desert fog water carries exceptionally high concentrations of sulphate, which may be responsible for the formation of gypsum deposits in the desert. The work suggests that Namibian fog water is at least as clean as has been reported from other coastal deserts in South America and Arabia, and provides a source of very clean water for the coastal desert region of south-western Africa. It does not appear that fog is an efficient sulphur source for the formation of the gypsum deposits, unless rare events with high concentrations of marine sulphur compounds occur.

Development and Testing of a Power Trough System Using a Structurally-Efficient, High-Performance, Large-Aperture Concentrator with Thin Glass Reflector and Focal Point Rotation

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

May, E. K.; Forristall, R.

2005-11-01

Industrial Solar Technology has assembled a team of experts to develop a large-aperture parabolic trough for the electric power market that moves beyond cost and operating limitations of 1980's designs based on sagged glass reflectors. IST's structurally efficient space frame design will require nearly 50% less material per square meter than a Solel LS-2 concentrator and the new trough will rotate around the focal point. This feature eliminates flexhoses that increase pump power, installation and maintenance costs. IST aims to deliver a concentrator module costing less than $100 per square meter that can produce temperatures up to 400 C. Themore » IST concentrator is ideally suited for application of front surface film reflectors and ensures that US corporations will manufacture major components, except for the high temperature receivers.« less

Occurrence of phthalic acid esters in source waters: a nationwide survey in China during the period of 2009-2012.

PubMed

Liu, Xiaowei; Shi, Jianghong; Bo, Ting; Zhang, Hui; Wu, Wei; Chen, Qingcai; Zhan, Xinmin

2014-01-01

The first nationwide survey of six phthalic acid esters (PAEs) (diethyl phthalate (DEP); dimethyl phthalate (DMP); di-n-butyl phthalate (DBP); butyl benzyl phthalate (BBP); bis(2-ethylhexyl) phthalate (DEHP); di-n-octyl phthalate (DnOP)) in source waters was conducted in China. The results showed these PAEs were ubiquitous in source waters. DBP and DEHP were the most frequently detected with high concentrations ranging nd-1.52 μg/L and nd-6.35 μg/L, respectively. These PAEs concentrations (except DBP) in surface water (rivers, lakes and reservoirs) were generally higher than those in groundwater; DBP had high concentrations in groundwater in Northeast China (Liao River Basin) and North China (Hai River Basin). Their concentrations in the northern regions were generally higher than those in the southern and eastern regions; particularly, in North China. Three short-chain PAEs (DMP, DEP and DBP) were detected with high concentrations in Hai River Basin, Pearl River Basin and Yellow River Basin. Copyright © 2013 Elsevier Ltd. All rights reserved.

Cholesterol-lowering effect of kori-tofu protein and its high-molecular-weight fraction content.

PubMed

Ishiguro, Takahiro; Tatsunokuchi, Seiji; Mitsui, Nobuo; Kayahara, Hisataka; Murasawa, Hisashi; Konishi, Yotaro; Nagaoka, Satoshi

2011-01-01

The serum total cholesterol concentration was significantly lower in the kori-tofu feeding group than in the soy protein isolate (SPI) group, except on the 28th day of the experiment. The high-molecular-weight fraction (HMF) content of the kori-tofu protein was significantly higher than that of SPI. This difference in the HMF content may have influenced the cholesterol-lowering effect of the protein.

Evidence That Isoprene Emission Is Not Limited by Cytosolic Metabolites. Exogenous Malate Does Not Invert the Reverse Sensitivity of Isoprene Emission to High [CO2].

PubMed

Rasulov, Bahtijor; Talts, Eero; Bichele, Irina; Niinemets, Ülo

2018-02-01

Isoprene is synthesized via the chloroplastic 2- C -methyl-d-erythritol 4-phosphate/1-deoxy-d-xylulose 5-phosphate pathway (MEP/DOXP), and its synthesis is directly related to photosynthesis, except under high CO 2 concentration, when the rate of photosynthesis increases but isoprene emission decreases. Suppression of MEP/DOXP pathway activity by high CO 2 has been explained either by limited supply of the cytosolic substrate precursor, phospho enol pyruvate (PEP), into chloroplast as the result of enhanced activity of cytosolic PEP carboxylase or by limited supply of energetic and reductive equivalents. We tested the PEP-limitation hypotheses by feeding leaves with the PEP carboxylase competitive inhibitors malate and diethyl oxalacetate (DOA) in the strong isoprene emitter hybrid aspen ( Populus tremula × Populus tremuloides ). Malate feeding resulted in the inhibition of net assimilation, photosynthetic electron transport, and isoprene emission rates, but DOA feeding did not affect any of these processes except at very high application concentrations. Both malate and DOA did not alter the sensitivity of isoprene emission to high CO 2 concentration. Malate inhibition of isoprene emission was associated with enhanced chloroplastic reductive status that suppressed light reactions of photosynthesis, ultimately leading to reduced isoprene substrate dimethylallyl diphosphate pool size. Additional experiments with altered oxygen concentrations in conditions of feedback-limited and non-feedback-limited photosynthesis further indicated that changes in isoprene emission rate in control and malate-inhibited leaves were associated with changes in the share of ATP and reductive equivalent supply for isoprene synthesis. The results of this study collectively indicate that malate importantly controls the chloroplast reductive status and, thereby, affects isoprene emission, but they do not support the hypothesis that cytosolic metabolite availability alters the response of isoprene emission to changes in atmospheric composition. © 2018 American Society of Plant Biologists. All Rights Reserved.

Polyaniline-ZnO nanocomposites as ethanol gas sensors

NASA Astrophysics Data System (ADS)

Talegaonkar, Janhavi; Patil, Y. B.; Patil, D. R.

2018-05-01

Polyaniline and it`s nanocomposites with ZnO were successfully synthesized by photo-induced polymerization method with various concentrations of ZnO, followed by characterizations viz. SEM, EDAX, XRD, FTIR and UV-Vis. Thick films of synthesized powders were fabricated by screen printing technique for monitoring various gases at different operating temperatures and at various gas concentrations. CuO activated polyaniline-ZnO nano-composite exhibits maximum response of ethanol gas at room temperature. The sensor exhibits high sensitivity, highest selectivity, quick response, fast recovery, long term stability, etc. An exceptional sensitivity was found to low concentrations of ethanol gas at room temperature and no cross sensitivity was observed even to high concentrations of other hazardous and polluting gases. The efforts have been made to develop the ethanol sensor based on PANI and its nanocomposites. The effects of microstructure and surfactant concentration on the ethanol response, selectivity, response and recovery of the sensor in the presence of ethanol gas were studied and discussed.

Brain Tocopherols Related to Alzheimer Disease Neuropathology in Humans

PubMed Central

Morris, Martha Clare; Schneider, Julie A; Li, Hong; Tangney, Christy C; Nag, Sukrit; Bennett, David A; Honer, William G.; Barnes, Lisa

2014-01-01

Randomized trials of α-tocopherol supplements on cognitive decline are negative whereas studies of dietary tocopherols show benefit. We investigated these inconsistencies by analyzing the relations of α- and γ-tocopherol brain concentrations to Alzheimer disease (AD) neuropathology among 115 deceased participants of the prospective Rush Memory and Aging Project. Associations of amyloid load and neurofibrillary tangle severity with brain tocopherol concentrations were examined in separate adjusted linear regression models. γ-tocopherol concentrations were associated with lower amyloid load (β= −2.10; p=.002) and lower neurofibrillary tangle severity (β= −1.16; p=0.02). Concentrations of α-tocopherol were not associated with AD neuropathology except as modified by γ-tocopherol: high α-tocopherol was associated with higher amyloid load when γ-tocopherol levels were low and with lower amyloid levels when γ-tocopherol levels were high (P for interaction=0.03). Brain concentrations of γ- and α-tocopherols may be associated with AD neuropathology in interrelated, complex ways. Randomized trials should consider the contribution of γ-tocopherol. PMID:24589434

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in sediments from an urban- and industrial-impacted subtropical estuary (Babitonga Bay, Brazil).

PubMed

Rizzi, Juliane; Taniguchi, Satie; Martins, César C

2017-06-15

Babitonga Bay is a large estuary, which has been under pressure from anthropogenic activities coexisting with a natural area of Atlantic rainforest and mangrove systems. The concentration of persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) was determined to evaluate the contamination status and the determine possible pollution sources in the estuary. The ∑DDT (sum of DDT, DDE and DDD concentrations) was the predominant OCP group, with concentrations ranging from

Influence of the bubble-bubble interaction on destruction of encapsulated microbubbles under ultrasound.

PubMed

Yasui, Kyuichi; Lee, Judy; Tuziuti, Toru; Towata, Atsuya; Kozuka, Teruyuki; Iida, Yasuo

2009-09-01

Influence of the bubble-bubble interaction on the pulsation of encapsulated microbubbles has been studied by numerical simulations under the condition of the experiment reported by Chang et al. [IEEE Trans. Ultrason Ferroelectr. Freq. Control 48, 161 (2001)]. It has been shown that the natural (resonance) frequency of a microbubble decreases considerably as the microbubble concentration increases to relatively high concentrations. At some concentration, the natural frequency may coincide with the driving frequency. Microbubble pulsation becomes milder as the microbubble concentration increases except at around the resonance condition due to the stronger bubble-bubble interaction. This may be one of the reasons why the threshold of acoustic pressure for destruction of an encapsulated microbubble increases as the microbubble concentration increases. A theoretical model for destruction has been proposed.

Ground-water appraisal in northwestern Big Stone County, west-central Minnesota

USGS Publications Warehouse

Soukup, W.G.

1980-01-01

Samples of water were collected for chemical analysis from wells in the surficial outwash, buried outwash, and Cretaceous aquifers. With the exception of nitrate, the greatest difference in chemical quality was between samples from the buried outwash and Cretaceous aquifers. Water from Cretaceous aquifers is softer than water from the outwash aquifers, but contains concentrations of sodium and boron that are high enough to damage soils and crops if used for irrigation. Nitrate concentrations exceeded the Minnesota Pollution Control Agency's recommended limits for drinking water in one sample from the surficial aquifer.

Seasonal variations in the concentrations of metals in Crassostrea corteziensis from Sonora, México.

PubMed

García-Rico, L; Tejeda-Valenzuela, L; Burgos-Hernández, A

2010-08-01

This study examines seasonal variations in the concentrations of Cd, Cu, Pb, and Hg in experimentally cultured Crassostrea corteziensis, an oyster species known to have high resistance to physical and chemical stressors. The highest levels of Cd (4.92 mg/kg), Cu (3.45 mg/kg), and Pb (0.67 mg/kg) were detected in oyster samples collected during the summer, while Hg concentrations were similar (0.03 to 0.04 mg/kg) throughout all seasons. Results indicate that except for Cd, Crassostrea corteziensis accumulates metals to levels below those recommended by the US. FDA and the Mexican government. For Cd, its concentration correlates more strongly with the temperature of the oyster's environment rather than to the oyster growth cycle.

Zwitterionic Antifouling Coatings for the Purification of High-Salinity Shale Gas Produced Water.

PubMed

Yang, Rong; Goktekin, Esma; Gleason, Karen K

2015-11-03

Fouling refers to the undesirable attachment of organic molecules and microorganisms to submerged surfaces. It is an obstacle to the purification of shale gas produced water and is currently without an effective solution due to the highly contaminated nature of produced water. Here, we demonstrate the direct vapor application of a robust zwitterionic coating to a variety of substrates. The coating remains unprecedentedly hydrophilic, smooth, and effectively antifouling in extremely high salinity solutions (with salt concentration of 200,000 ppm). The fouling resistance is assessed rapidly and quantitatively with a molecular force spectroscopy-based method and corroborated using quartz crystal microbalance system with dissipation monitoring. Grazing angle attenuated total reflectance Fourier transform infrared is used in combination with X-ray photoelectron spectroscopy, atomic force microscope, and in situ spectroscopic ellipsometry to lend insight into the underlying mechanism for the exceptional stability and effectiveness of the zwitterionic coating under high-salinity conditions. A unique coating architecture, where the surface is concentrated with mobile zwitterionic moieties while the bulk is cross-linked to enhance coating durability, was discovered to be the origin of its stable fouling resistance under high salinity. Combined with previously reported exceptional stability in highly oxidative environments and strong fouling resistance to oil and grease, the zwitterionic surface here has the potential to enable low-cost, membrane-based techniques for the purification of produced water and to eventually balance the favorable economics and the concerning environmental impacts of the hydraulic fracturing industry.

Accumulation status, sources and phytoavailability of metals in greenhouse vegetable production systems in Beijing, China.

PubMed

Xu, Li; Lu, Anxiang; Wang, Jihua; Ma, Zhihong; Pan, Ligang; Feng, Xiaoyuan; Luan, Yunxia

2015-12-01

The accumulation status, sources and phytoavailability of selected metals in greenhouse vegetable production systems in peri-urban areas of Beijing were investigated. The mean concentrations of As, Cd, Cr, Hg and Pb in greenhouse soils were 8.44, 0.25, 69.0, 0.09 and 22.0 mg kg(-1), dw, respectively. According to principal component analysis, As, Cd, Cr and Hg are mainly from anthropogenic source, but Pb is likely from natural source. Metal concentrations in all vegetable samples were decreased in the order of Cr>As>Pb>Cd>Hg. Compared with root and fruit vegetables, leaf vegetables had relatively high concentrations and transfer factors of heavy metals, except for Cd. By including soil pH, OM and greenhouse soil metals, 10 empirical models were derived using stepwise multiple linear regression analysis to predict heavy metal concentrations in the edible parts of different vegetables. Among the different vegetable groups, the highest intakes of metals occurred through consumption of leaf vegetables for the two age groups, except for Cd. The HI value of the studied metals were all below 1, indicating that consumption of vegetables grown in greenhouse soils was of low risk to consumers in our study area. Copyright © 2015 Elsevier Inc. All rights reserved.

Monitoring marine recreational water quality using multiple microbial indicators in an urban tropical environment

PubMed Central

Shibata, Tomoyuki; Solo-Gabriele, Helena M.; Fleming, Lora E.; Elmir, Samir

2008-01-01

The microbial water quality at two beaches, Hobie Beach and Crandon Beach, in Miami-Dade County, Florida, USA was measured using multiple microbial indicators for the purpose of evaluating correlations between microbes and for identifying possible sources of contamination. The indicator microbes chosen for this study (enterococci, Escherichia coli, fecal coliform, total coliform and C. perfringens) were evaluated through three different sampling efforts. These efforts included daily measurements at four locations during a wet season month and a dry season month, spatially intensive water sampling during low- and high-tide periods, and a sand sampling effort. Results indicated that concentrations did not vary in a consistent fashion between one indicator microbe and another. Daily water quality frequently exceeded guideline levels at Hobie Beach for all indicator microbes except for fecal coliform, which never exceeded the guideline. Except for total coliform, the concentrations of microbes did not change significantly between seasons in spite of the fact that the physical–chemical parameters (rainfall, temperature, pH, and salinity) changed significantly between the two monitoring periods. Spatially intense water sampling showed that the concentrations of microbes were significantly different with distance from the shoreline. The highest concentrations were observed at shoreline points and decreased at offshore points. Furthermore, the highest concentrations of indicator microbe concentrations were observed at high tide, when the wash zone area of the beach was submerged. Beach sands within the wash zone tested positive for all indicator microbes, thereby suggesting that this zone may serve as the source of indicator microbes. Ultimate sources of indicator microbes to this zone may include humans, animals, and possibly the survival and regrowth of indicator microbes due to the unique environmental conditions found within this zone. Overall, the results of this study indicated that the concentrations of indicator microbes do not necessarily correlate with one another. Exceedence of water quality guidelines, and thus the frequency of beach advisories, depends upon which indicator microbe is chosen. PMID:15261551

Effects of an antiatherogenic diet during pregnancy on markers of maternal and fetal endothelial activation and inflammation: the CARRDIP study

PubMed Central

Khoury, J; Henriksen, T; Seljeflot, I; Mørkrid, L; Frøslie, KF; Tonstad, S

2007-01-01

Objective To study the effect of an antiatherogenic diet on maternal and cord blood concentrations of systemic biomarkers of endothelial cell activation, haemostasis and inflammation. Design Single blinded randomised controlled clinical trial. Setting Obstetric outpatient clinic and maternity unit of a university hospital in Norway. Population Nonsmoking pregnant women aged 21–38 years carrying a single fetus and with no previous pregnancy-related complications. Methods Subjects (n = 290) were randomised to continue their usual diet or to adopt a diet low in saturated fat and cholesterol from gestational week 17–20 to birth. Soluble forms of cellular adhesion molecules, high-sensitivity C-reactive protein (CRP) and haemostatic markers were measured at 17–20 weeks of gestation (baseline) and subsequently up to week 36. All the above, except CRP, were also measured in cord blood. Main outcome measures Concentrations of maternal and fetal biomarkers and maternal CRP. Results All biomarkers except CRP levels increased significantly during the study period in both the intervention and control groups. None of the maternal or fetal biomarkers were influenced by the intervention (P > 0.05) except for a tendency to lower concentrations of cord blood tissue plasminogen activator antigen in the intervention group compared with the control group, median (interquartile range) 5.4 ng/ml (3.1–7.7) versus 5.8 ng/ml (3.5–11.8), P = 0.05. Conclusion An antiatherogenic diet in pregnancy did not significantly influence maternal or fetal blood concentrations of a range of biomarkers for inflammation. Thus, the previously reported effects of a cholesterol-lowering diet on maternal lipid profile and preterm delivery (<37 complete weeks of gestation) do not seem to involve changes in the systemic inflammatory responses of pregnancy. PMID:17217362

Spermicidal activity of some halides.

PubMed

Narayan, J P; Singh, J N

1979-01-01

Though most of the metallic ions are spermicidal in action, the present investigation emphasises the spermicidal activity of anions. Among the inorganic compounds screened at 4 concentrations (0.01%, 0.1%, 1% and 5%) halides are mainly spermicidal, except NaCl, KCl & CsCl which are spermiostatic; sulphates and nitrates are mainly spermiostatic except ZnSO4 at 1% concentration and above; CuSO4, Al2 (SO4)3, Uo2(NO3)2.6H2O and AgNO3 at 5% concentration where they become spermicidal.

Heavy metal concentrations in redeveloping soil of mine spoil under plantations of certain native woody species in dry tropical environment, India.

PubMed

Singh, Anand N; Zeng, De-hui; Chen, Fu-sheng

2005-01-01

Total concentration of heavy metals (Cd, Cr, Cu, Fe, Pb, Ni, Mn and Zn) was estimated in the redeveloping soil of mine spoil under 5-yr old plantations of four woody species namely: Albizia lebbeck, Albizia procera, Tectona grandis and Dendrocalamus strictus. The data recorded in the present study were compared with other unplanted coal mine spoil colliery, which was around to the study site and adjoining area of dry tropical forest. Among all the heavy metals, the maximum concentration was found for Fe and minimum for Cd. However, among all four species, total concentrations of these heavy metals were recorded maximally in the plantation plots of T. grandis except for Fe, while minimally in A. lebbeck except for Zn, whereas, the maximum concentration of Fe and Zn was in the plantation plots of D. strictus and A. procera. Statistical analysis revealed significant differences due to species for all the heavy metals except Cu. Among four species, A. lebbeck, A. procera and D. strictus showed more efficient for reducing heavy metal concentrations whereas T. grandis was not more effective to reduce heavy metal concentrations in redeveloping soil of mine spoil.

A girl with headache, confusion and green urine.

PubMed

Hufschmidt, Andreas; Krisch, Alexandra; Peschen, I

2009-07-01

The case of a 17-year-old girl with a history of headache, blurred vision, confusion, ataxia and syncope is presented. On admission, she had already recovered except for a slurring of speech. Her urine was found to be green. Screening for illegal drugs was negative, but gas chromatography with subsequent mass spectroscopy (GC-MS) revealed an extremely high concentration of flupirtine.

An assessment of the radiological scenario around uranium mines in Singhbhum East district, Jharkhand, India.

PubMed

Tripathi, R M; Sahoo, S K; Mohapatra, S; Patra, A C; Lenka, P; Dubey, J S; Jha, V N; Puranik, V D

2012-07-01

The present work deals with the prevalent radiological scenario around uranium-mining sites in the Singhbhum East district of Jharkhand state, India. The concentration of naturally occurring radioactive materials (NORMs) was estimated from 27 soil samples collected around three regions in the study area, namely Bagjata, Turamdih and Jaduguda. The mean activity concentrations of (238)U in Bagjata, Turamdih and Jaduguda regions were found to be 128.6, 95.7 and 49.2 Bq kg(-1), respectively. Similarly for (232)Th and (40)K the activity concentrations were found to be 57.3, 78.4, 68.9 and 530, 425 and 615 Bq kg(-1) in the Bagjata, Turamdih and Jaduguda regions, respectively, which are comparable with other reported values worldwide, except for some high values. The calculated gamma dose rate, obtained from the concentrations of (238)U, (232)Th and (40)K in the samples, was compared with the observed dose rate in air. A good correlation (0.96) was observed between the calculated and the observed gamma dose rate. The annual outdoor effective dose rate was estimated and the values falls between 0.04-0.3, 0.07-0.3 and 0.07-.14 mSv y(-1) with mean values of 0.14, 0.12 and 0.11 mSv y(-1) for the Bagjata, Turamdih and Jaduguda regions, respectively. The terrestrial dose rates in all the three regions are comparable with other reported values worldwide, except for a few high values in Greece, Rio Grande Do Norte (Brazil) and Kalpakkam (India).

Sensitivity analysis of source regions to PM2.5 concentration at Fukue Island, Japan.

PubMed

Ikeda, Kohei; Yamaji, Kazuyo; Kanaya, Yugo; Taketani, Fumikazu; Pan, Xiaole; Komazaki, Yuichi; Kurokawa, Jun-ichi; Ohara, Toshimasa

2014-04-01

The authors analyze the sensitivities of source regions in East Asia to PM2.5 (particulate matter with an aerodynamic diameter of < or = 2.5 microm) concentration at Fukue Island located in the western part of Japan by using a regional chemical transport model with emission sensitivity simulations for the year 2010. The temporal variations in PM2.5 concentration are generally reproduced, but the absolute concentration is underestimated by the model. Chemical composition of PM2.5 in the model is compared with filter sampling data in spring; simulated sulfate, ammonium, and elemental carbon are consistent with observations, but mass concentration of particulate organic matters is underestimated. The relative contribution from each source region shows the seasonal variation, especially in summer. The contribution from central north China (105 degrees E-124 degrees E, 34 degrees N-42 degrees N) accounts for 50-60% of PM2.5 at Fukue Island except in summer; it significantly decreases in summer (18%). Central south China (105 degrees E-123 degrees E, 26 degrees N-34 degrees N) has the relative contribution of 15-30%. The contribution from the Korean Peninsula is estimated at about 10% except in summer. The domestic contribution accounts for about 7% in spring and autumn and increases to 19% in summer. We also estimate the relative contribution to daily average concentration in high PM2.5 days (> 35 microg m(-3)). Central north China has a significant contribution of 60-70% except in summer. The relative contribution from central south China is estimated at 46% in summer and about 30% in the other seasons. The contributions from central north and south China on high PM2.5 days are generally larger than those of their seasonal mean contributions. The domestic contribution is smaller than the seasonal mean value in every season; it is less than 10% even in summer. These model results suggest that foreign anthropogenic sources have a substantial impact on attainment of the atmospheric environmental standard of Japan at Fukue Island. The contribution from several source regions in East Asia to PM2.5 concentration at Fukue Island, a remote island located in the western part of Japan and close to the Asian continent, is estimated using a three-dimensional chemical transport model. The model results suggest that PM2.5 that is attributed to foreign anthropogenic sources have a larger contribution than that of domestic pollution and have a substantial impact on attainment of the atmospheric environmental standard of Japan at Fukue Island.

Major and trace elements in igneous rocks from Apollo 15.

NASA Technical Reports Server (NTRS)

Helmke, P. A.; Blanchard, D. P.; Haskin, L. A.; Telander, K.; Weiss, C.; Jacobs, J. W.

1973-01-01

The concentrations of major and trace elements have been determined in igneous rocks from Apollo 15. All materials analyzed have typical depletions of Eu except for minerals separated from sample 15085. Four samples have concentrations of trace elements that are similar to those of KREEP. The samples of mare basalt from Apollo 15 have higher concentrations of FeO, MgO, Mn, and Cr and lower concentrations of CaO, Na2O, K2O, and rare-earth elements (REE) as compared to the samples of mare basalt from Apollos 11, 12, and 14. The samples can be divided into two groups on the basis of their normative compositions. One group is quartz normative and has low concentrations of FeO while the other is olivine normative and has high concentrations of FeO. The trace element data indicate that the samples of olivine normative basalt could be from different portions of a single lava flow.

Assessment of heavy metal pollution, spatial distribution and origin in agricultural soils along the Sinú River Basin, Colombia.

PubMed

Marrugo-Negrete, José; Pinedo-Hernández, José; Díez, Sergi

2017-04-01

The presence of metals in agricultural soils from anthropogenic activities such as mining and agricultural use of metals and metal-containing compounds is a potential threat for human health through the food chain. In this study, the concentration of heavy metals in 83 agricultural soils irrigated by the Sinú River, in northern Colombia, affected by mining areas upstream and inundated during seasonal floods events were determined to evaluate their sources and levels of pollution. The average concentrations of Cu, Ni, Pb, Cd, Hg and Zn were 1149, 661, 0.071, 0.040, 0.159 and 1365mg/kg respectively and exceeded the world normal averages, with the exception of Pb and Cd. Moreover, all values surpassed the background levels of soils in the same region. Soil pollution assessment was carried out using contamination factor (CF), enrichment factor (EF), geoaccumulation index (Igeo) and a risk assessment code (RAC). According to these indexes, the soils show a high degree of pollution of Ni and a moderate to high contamination of Zn and Cu; whereas, Pb, Cd and Hg present moderate pollution. However, based on the RAC index, a low environmental risk is found for all the analysed heavy metals. Multivariate statistical analyses, principal component and cluster analyses, suggest that soil contamination was mainly derived from agricultural practices, except for Hg, which was caused probably by atmospheric and river flow transport from upstream gold mining. Finally, high concentrations of Ni indicate a mixed pollution source from agricultural and ferronickel mining activities. Copyright © 2017 Elsevier Inc. All rights reserved.

Simultaneous determination of sulfonamides, tetracyclines and tiamulin in swine wastewater by solid-phase extraction and liquid chromatography-mass spectrometry.

PubMed

Ben, Weiwei; Qiang, Zhimin; Adams, Craig; Zhang, Heqing; Chen, Liping

2008-08-22

Little is known about the contamination level of antibiotics in swine wastewater in China. The highly complex matrix of swine wastewater, which generally has a chemical oxygen demand (COD) concentration as high as 15,000 mg/L, makes it difficult to detect antibiotics at trace levels. In this work, a highly selective and sensitive analytical method was developed for simultaneous determination of three classes of commonly used veterinary antibiotics including five sulfonamides, three tetracyclines and one macrolide in swine wastewater using solid-phase extraction (SPE) and liquid chromatography-mass spectrometry (LC-MS). The method detection limits (MDL) in the swine wastewater were determined to be between 5 and 91 ng/L, depending on specific antibiotics. Except sulfamethizole, all the other eight antibiotics were detected in the swine wastewaters collected from three concentrated swine feeding plants located in the Beijing (China) area, showing a concentration range of 0.62-32.67 microg/L. These results reveal the representative concentration levels of selected antibiotics in the swine wastewaters of Beijing area.

Distribution and accumulation of polybrominated diphenyl ethers (PBDEs) in Hong Kong mangrove sediments.

PubMed

Zhu, Haowen; Wang, Ying; Wang, Xiaowei; Luan, Tiangang; Tam, Nora F Y

2014-01-15

Polybrominated diphenyl ethers (PBDEs) have been used extensively as brominated flame retardants in various polymers, and have become serious environmental contaminants, particularly in coastal sediments. Mangrove wetlands are important coastal ecosystems in tropical and subtropical regions, and mangrove sediments are often the pollutant sinks due to their close proximity with human activities. In Hong Kong, sediment samples collected from five mangrove swamps were found to be contaminated with PBDEs and the eight measured BDE congeners, including BDE-28, -47, -99, -100, -153, -154, -183 and -209 were detected in all mangrove sediments, indicating that these pollutants were widespread in Hong Kong mangrove wetlands. Among the five swamps, relatively high concentrations of PBDEs were recorded in Mai Po mangrove swamp in the northwestern Hong Kong, which is part of the RAMSAR site but is severely influenced by the pollution from the Pearl River Delta. The depth profile of PBDEs in sediment cores collected from Mai Po also showed the inputs of PBDEs in this mangrove swamp increased year by year. In all sediments, the concentrations of BDE-209 were 1-2 orders of magnitude higher than the other congeners in the same sediment. The concentrations of BDE-209 and ∑PBDEs (defined as the sum of seven targeted BDE congeners except BDE-209) ranged from 1.53 to 75.9 ng g(-1) and from 0.57 to 14.4 ng g(-1), respectively. Among the targeted BDE congeners except BDE-209, slightly different composition was recorded among samples collected from different locations, with BDE-153 and -183 being the pre-dominated congeners. In all mangrove swamps, except Tai O in the southwest of Hong Kong, ∑PBDEs concentrations showed a common trend of landward>seaward>mudflat. The concentrations of ∑PBDEs were significantly correlated with total organic matter (TOM) content in sediments but not with the sediment particle sizes in each mangrove swamp. © 2013.

Determination of relationship between sensory viscosity rating and instrumental flow behaviour of soluble dietary fibers.

PubMed

Arora, Simran Kaur; Patel, A A; Kumar, Naveen; Chauhan, O P

2016-04-01

The shear-thinning low, medium and high-viscosity fiber preparations (0.15-1.05 % psyllium husk, 0.07-0.6 % guar gum, 0.15-1.20 % gum tragacanth, 0.1-0.8 % gum karaya, 0.15-1.05 % high-viscosity Carboxy Methyl Cellulose and 0.1-0.7 % xanthan gum) showed that the consistency coefficient (k) was a function of concentration, the relationship being exponential (R(2), 0.87-0.96; P < 0.01). The flow behaviour index (n) (except for gum karaya and CMC) was exponentially related to concentration (R(2), 0.61-0.98). The relationship between k and sensory viscosity rating (SVR) was essentially linear in nearly all cases. The SVR could be predicted from the consistency coefficient using the regression equations developed. Also, the relationship of k with fiber concentration would make it possible to identify the concentration of a particular gum required to have desired consistency in terms of SVR.

Vegetation and Cold Trapping Modulating Elevation-dependent Distribution of Trace Metals in Soils of a High Mountain in Eastern Tibetan Plateau.

PubMed

Bing, Haijian; Wu, Yanhong; Zhou, Jun; Li, Rui; Luo, Ji; Yu, Dong

2016-04-07

Trace metals adsorbed onto fine particles can be transported long distances and ultimately deposited in Polar Regions via the cold condensation effect. This study indicated the possible sources of silver (Ag), cadmium (Cd), copper (Cu), lead (Pb), antimony (Sb) and zinc (Zn) in soils on the eastern slope of Mt. Gongga, eastern Tibetan Plateau, and deciphered the effects of vegetation and mountain cold condensation on their distributions with elevation. The metal concentrations in the soils were comparable to other mountains worldwide except the remarkably high concentrations of Cd. Trace metals with high enrichment in the soils were influenced from anthropogenic contributions. Spatially, the concentrations of Cu and Zn in the surface horizons decreased from 2000 to 3700 m a.s.l., and then increased with elevation, whereas other metals were notably enriched in the mid-elevation area (approximately 3000 m a.s.l.). After normalization for soil organic carbon, high concentrations of Cd, Pb, Sb and Zn were observed above the timberline. Our results indicated the importance of vegetation in trace metal accumulation in an alpine ecosystem and highlighted the mountain cold trapping effect on trace metal deposition sourced from long-range atmospheric transport.

Appearance and quantification of infectious hematopoietic necrosis virus in female sockeye salmon (Oncorhynchus nerka) during their spawning migration

USGS Publications Warehouse

Mulcahy, D.; Jenes, C.K.; Pascho, R.J.

1984-01-01

The incidence and amount of infectious hematopoietic necrosis (IHN) virus was determined in 10 organs and body fluids from each of 100 female sockeye salmon(Oncorhynchus nerka) before, during, and after their spawning migration into freshwater. Virus was found in high concentrations only in fish sampled during and after spawning. Infection rates increased from nil to 100 percent within 2 weeks. In spawning fish, incidences of IHN virus were high in all organs and fluids except brain and serum, and the highest concentrations were in the pyloric caeca and lower gut. Immediately before spawning, IHN virus was found most frequently in the gills, less frequently in the pyloric caeca and spleen, and rarely in other organs.

Quality of ground water in the Biscayne Aquifer in Miami-Dade, Broward, and Palm Beach counties, Florida, 1996-1998, with emphasis on contaminants

USGS Publications Warehouse

Bradner, Anne; McPherson, Benjamin F.; Miller, Ronald L.; Kish, George; Bernard, Bruce

2005-01-01

The high permeability of the sand and limestone sediments and shallow water table of the Biscayne aquifer make ground water vulnerable to contamination by human activities. To assess potential contamination in the aquifer, untreated ground water was sampled from 30 public-supply wells (40-165 feet deep) in Broward, Miami-Dade, and Palm Beach Counties, 32 shallow wells (10-50 feet deep) in a recently urbanized (residential and light commercial) part of Broward County, and 3 shallow reference wells in Broward County. Results from sample analyses indicate that major ions, pH, dissolved oxygen, nutrients, and trace element concentrations were generally within the range indicative of background concentrations, except for: (1) substantially higher bromide concentrations in water from public-supply wells in southern Miami-Dade County; (2) a few relatively high (greater than 2 milligrams per liter) concentrations of nitrate in water from public-supply wells near agricultural lands in Miami-Dade and southern Broward Counties; and (3) a few relatively high concentrations of arsenic (greater than 10 micrograms per liter) in water from some shallow urban wells near golf courses. Pesticides were detected in every public-supply well, in most of the shallow, urban monitoring wells (78 percent), and in one reference well; however, no pesticide concentration exceeded any drinking-water standard. Fifteen different pesticides or their degradation products were detected. The most frequently detected pesticides were atrazine and tebuthiuron; less frequently detected were the herbicides diuron, fenuron, prometon, metolachlor, simazine, and 2,6-diethylaniline. Volatile organic compounds (VOCs) were detected in most of the public-supply wells (77 percent) and shallow, urban wells (91 percent) and in two of the three reference wells. Thirty-two different VOCs were detected in ground water in the Biscayne aquifer, with cis-1,2-dichloroethene the most frequently detected VOC in the public-supply wells, followed by methyl tert-butyl ether (MTBE), 1,4-dichlorobenzene, and chloroform. Toluene, p-isopropyltoluene, and 1,2,4-trimethylbenzene were the most frequently detected VOCs in the shallow, urban wells. Concentrations of all VOCs were less than the maximum contaminant level (MCL) for public drinking water, except in two samples from public-supply wells near industrialized areas that had vinyl chloride concentrations (3 and 5 micrograms per liter) above the MCL of 1 microgram per liter.

Chlorinated, brominated, and perfluorinated contaminants in livers of polar bears from Alaska.

PubMed

Kannan, Kurunthachalam; Yun, Se Hun; Evans, Thomas J

2005-12-01

The existence of two subpopulations of polar bears in Alaska, the Beaufort Sea and the Chukchi Sea populations, has been documented. In this study, differences in concentrations and profiles of organochlorine pesticides, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and perfluorinated acids were examined in livers of polar bears from the two subpopulations in Alaska. Concentrations of most of the organohalogens analyzed were greater in the Beaufort Sea subpopulation than in the Chukchi Sea subpopulation, except for HCHs and perfluorononanoic acid (PFNA), which were high in samples from the Chukchi Sea subpopulation. Concentrations of chlordanes, PCBs, and perfluorooctanesulfonate (PFOS) were significantly different between the two subpopulations. Chlordane was the predominant contaminant in the Beaufort Sea population, and PFOS was the major contaminant in the Chukchi Sea population. Polar bears from the Beaufort Sea showed significantly higher proportions of more highly chlorinated PCBs than those from the Chukchi Sea. Concentrations of several perfluorinated acids were significantly correlated. Overall, the concentrations and profiles of organohalogens analyzed in the two subpopulations of polar bears suggest differences in the sources of exposures between the two regions of Alaska.

27 CFR 25.261 - General.

Code of Federal Regulations, 2010 CFR

2010-04-01

... TREASURY LIQUORS BEER Beer Concentrate § 25.261 General. (a) Authorized processes. A brewer may, in accordance with this subpart— (1) Produce concentrate from beer, (2) Reconstitute beer from concentrate, (3... treatment of concentrate. Beer reconstituted from concentrate in accordance with this subpart shall (except...

27 CFR 25.261 - General.

Code of Federal Regulations, 2013 CFR

2013-04-01

... TREASURY ALCOHOL BEER Beer Concentrate § 25.261 General. (a) Authorized processes. A brewer may, in accordance with this subpart— (1) Produce concentrate from beer, (2) Reconstitute beer from concentrate, (3... treatment of concentrate. Beer reconstituted from concentrate in accordance with this subpart shall (except...

27 CFR 25.261 - General.

Code of Federal Regulations, 2012 CFR

2012-04-01

... TREASURY LIQUORS BEER Beer Concentrate § 25.261 General. (a) Authorized processes. A brewer may, in accordance with this subpart— (1) Produce concentrate from beer, (2) Reconstitute beer from concentrate, (3... treatment of concentrate. Beer reconstituted from concentrate in accordance with this subpart shall (except...

27 CFR 25.261 - General.

Code of Federal Regulations, 2014 CFR

2014-04-01

... TREASURY ALCOHOL BEER Beer Concentrate § 25.261 General. (a) Authorized processes. A brewer may, in accordance with this subpart— (1) Produce concentrate from beer, (2) Reconstitute beer from concentrate, (3... treatment of concentrate. Beer reconstituted from concentrate in accordance with this subpart shall (except...

27 CFR 25.261 - General.

Code of Federal Regulations, 2011 CFR

2011-04-01

... TREASURY LIQUORS BEER Beer Concentrate § 25.261 General. (a) Authorized processes. A brewer may, in accordance with this subpart— (1) Produce concentrate from beer, (2) Reconstitute beer from concentrate, (3... treatment of concentrate. Beer reconstituted from concentrate in accordance with this subpart shall (except...

Pharmacokinetics of aniracetam and its metabolites in rats.

PubMed

Ogiso, T; Iwaki, M; Tanino, T; Ikeda, K; Paku, T; Horibe, Y; Suzuki, H

1998-05-01

The pharmacokinetics of aniracetam (AP), a new cognitive performance enhancer, and its main metabolites was investigated after intravenous (iv) and oral administrations to rat. The plasma levels of AP, 4-p-anisamidobutyric acid (ABA), and p-anisic acid (AA) were determined simultaneously by the HPLC method. The plasma concentrations of the parent drug and ABA quickly declined in a biexponential manner, with rapid terminal decay and a small mean residence time. However, AA yielded nonlinearly high levels at the initial times and the plasma concentrations of 2-pyrrolidinone (PD) were sustained over a relatively long time. When AA was administered intravenously, nonlinearity of the plasma concentrations was also found at higher doses. To describe the time course of the plasma levels of AP and its metabolites after iv administration, a pharmacokinetic model with seven compartments was applied, which included 10 first-order rate constants and one Michaelis-Menten constant. An approximate fit was obtained between the observed and calculated curves based on the model, except for the plasma concentrations of ABA. The plasma concentration-time profiles of AP and its metabolites following oral administration of AP (50 and 100 mg/kg) were similar to those after iv dosing, with the exception of PD, which showed much lower plasma levels than those after iv administration. Elimination of AP and ABA was rapid after oral dosing, and the bioavailability of AP was extremely small (11.4 and 8.6%). As a result, AP was largely metabolized to ABA, AA, and PD in rat.

Novel AlInN/GaN integrated circuits operating up to 500 °C

NASA Astrophysics Data System (ADS)

Gaska, R.; Gaevski, M.; Jain, R.; Deng, J.; Islam, M.; Simin, G.; Shur, M.

2015-11-01

High electron concentration in 2DEG channel of AlInN/GaN devices is remarkably stable over a broad temperature range, enabling device operation above 500 °C. The developed IC technology is based on three key elements: (1) exceptional quality AlInN/GaN heterostructure with very high carrier concentration and mobility enables IC fast operation in a broad temperature range; (2) heterostructure field effect transistor approach t provides fully planar IC structure which is easy to scale and to combine with the other high temperature electronic components; (3) fabrication advancements including novel metallization scheme and high-K passivation/gate dielectrics enable high temperature operation. The feasibility of the developed technology was confirmed by fabrication and testing of the high temperature inverter and differential amplifier ICs using AlInN/GaN heterostructures. The developed ICs showed stable performance with unit-gain bandwidth above 1 MHz and internal response time 45 ns at temperatures as high as 500 °C.

A comprehensive evaluation of the toxicology of cigarette ingredients: carbohydrates and natural products.

PubMed

Coggins, Christopher R E; Wagner, Karl A; Werley, Michael S; Oldham, Michael J

2011-06-01

Eleven carbohydrates and natural product ingredients were added individually to experimental cigarettes. A battery of tests was used to compare toxicity of mainstream smoke from these experimental cigarettes to matched control cigarettes without test ingredients. Smoke fractions from each cigarette type were evaluated using analytical chemistry; in vitro cytotoxicity (neutral red uptake) and in vitro bacterial (Salmonella) mutagenicity (five strains) testing. For 10 ingredients (β-cyclodextrin, cleargum, D-sorbitol, high fructose corn syrup, honey, invert sugar, maltodextrin, molasses, raisin juice concentrate, and sucrose), 90-day nose-only smoke inhalation studies using rats were also performed. In general, addition of each ingredient in experimental cigarettes resulted in minimal changes in smoke chemistry; the exceptions were D-sorbitol and sucrose, where reductions in amount of 60% to 80% of control values for some smoke constituents were noted. Additionally, each ingredient resulted in small increases in smoke formaldehyde concentrations. Except for a reduction in cytotoxicity by inclusion of maltodextrin and an increase by inclusion of plum juice concentrate, the cytotoxicity and mutagenicity results were unaffected by addition of the other ingredients in experimental cigarettes. There were also very few statistically significant differences within any of the 10 inhalation studies, and when present, the differences were largely sporadic and inconsistent between sexes. The carbohydrates and natural products tested here as ingredients in experimental cigarettes as a class increased formaldehyde, but resulted in minimal toxicological responses, even at high inclusion levels compared with the levels used in commercial cigarette products.

Combining contamination indexes, sediment quality guidelines and multivariate data analysis for metal pollution assessment in marine sediments of Cienfuegos Bay, Cuba.

PubMed

Peña-Icart, Mirella; Pereira-Filho, Edenir Rodrigues; Lopes Fialho, Lucimar; Nóbrega, Joaquim A; Alonso-Hernández, Carlos; Bolaños-Alvarez, Yoelvis; Pomares-Alfonso, Mario S

2017-02-01

The purpose of the present work was to combine several tools for assessing metal pollution in marine sediments from Cienfuegos Bay. Fourteen surface sediments collected in 2013 were evaluated. Concentrations of As, Cu, Ni, Zn and V decreased respect to those previous reported. The metal contamination was spatially distributed in the north and south parts of the bay. According to the contamination factor (CF) enrichment factor (EF) and index of geoaccumulation (I geo ), Cd and Cu were classified in that order as the most contaminated elements in most sediment. Comparison of the total metal concentrations with the threshold (TELs) and probable (PELs) effect levels in sediment quality guidelines suggested a more worrisome situation for Cu, of which concentrations were occasional associated with adverse biological effects in thirteen sediments, followed by Ni in nine sediments; while adverse effects were rarely associated with Cd. Probably, Cu could be considered as the most dangerous in the whole bay because it was classified in the high contamination levels by all indexes and, simultaneously, associated to occasional adverse effects in most samples. Despite the bioavailability was partially evaluated with the HCl method, the low extraction of Ni (<3% in all samples) and Cu (<55%, except sample 3) and the relative high extraction of Cd (50% or more, except sample 14) could be considered as an attenuating (Ni and Cu) or increasing (Cd) factor in the risk assessment of those element. Copyright © 2016. Published by Elsevier Ltd.

Regional and temporal variation in minor ions in groundwater of a part of a large river delta, southern India.

PubMed

Elumalai, Vetrimurugan; Brindha, K; Elango, L

2017-07-01

Impact of agricultural activities on groundwater can be determined from the concentration of nutrients present in groundwater. This study was carried out with the aim to assess the minor ions content of groundwater and to identify its sources, spatial, and seasonal variations in a part of the Cauvery River basin, southern India. Groundwater samples were collected from July 2007 to September 2009 and were analyzed for minor ions. These ions were in the order of dominance of nitrate> phosphate> bromide> fluoride> ammonium= nitrite> lithium. The concentration of ions tends to increase towards the coast except for fluoride. Increased concentration of ions identified in shallow wells than in deep wells with an exception of few locations indicates the impact of human activities. Relatively high concentration of agriculture-sourced nitrate was identified which pose a threat to groundwater suitability for agriculture and domestic usage. Combined influence of use of agrochemicals, improper sewage disposal, aquaculture activities, seawater intrusion due to heavy pumping near the coast, and natural weathering of aquifer materials are the major sources. Also, fine grain sediments of this area aid in poor flushing of the ions towards the sea resulting in accumulation of higher concentration of ions. A sustainable management strategy is essential to control the concentration of these ions, especially nitrate. Reduced use of fertilizers, increasing the rainfall recharge for diluting the pollutants in groundwater and maintaining the river flow for sufficiently longer period to reduce dependence on groundwater for irrigation can help to improve the situation.

Element accumulation in boreal bryophytes, lichens and vascular plants exposed to heavy metal and sulfur deposition in Finland.

PubMed

Salemaa, Maija; Derome, John; Helmisaari, Heljä-Sisko; Nieminen, Tiina; Vanha-Majamaa, Ilkka

2004-05-25

Macronutrient (N, P, K, Mg, S, Ca), heavy metal (Fe, Zn, Mn, Cu, Ni, Cd, Pb) and Al concentrations in understorey bryophytes, lichens and vascular plant species growing in Scots pine forests at four distances from the Harjavalta Cu-Ni smelter (0.5, 2, 4 and 8 km) were compared to those at two background sites in Finland. The aim was to study the relationship between element accumulation and the distribution of the species along a pollution gradient. Elevated sulfur, nitrogen and heavy metal concentrations were found in all species groups near the pollution source. Macronutrient concentrations tended to decrease in the order: vascular plants>bryophytes>lichens, when all the species groups grew on the same plot. Heavy metal concentrations (except Mn) were the highest in bryophytes, followed by lichens, and were the lowest in vascular plants. In general, vascular plants, being capable of restricting the uptake of toxic elements, grew closer to the smelter than lichens, while bryophytes began to increase in the understorey vegetation at further distances from the smelter. A pioneer moss (Pohlia nutans) was an exception, because it accumulated considerably higher amounts of Cu and Ni than the other species and still survived close to the smelter. The abundance of most of the species decreased with increasing Cu and Ni concentrations in their tissues. Cetraria islandica, instead, showed a positive relationship between the abundance and Cu, Ni and S concentrations of the thallus. It is probable that, in addition to heavy metals, sporadically high SO(2) emissions have also affected the distribution of the plant species.

Phenolic characterization and variability in leaves, stems and roots of Micro-Tom and patio tomatoes, in response to nitrogen limitation.

PubMed

Larbat, Romain; Paris, Cédric; Le Bot, Jacques; Adamowicz, Stéphane

2014-07-01

Phenolics are implicated in the defence strategies of many plant species rendering their concentration increase of putative practical interest in the field of crop protection. Little attention has been given to the nature, concentration and distribution of phenolics within vegetative organs of tomato (Solanum lycopersicum. L) as compared to fruits. In this study, we extensively characterized the phenolics in leaves, stems and roots of nine tomato cultivars using high-performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry (LC-MS(n)) and assessed the impact of low nitrogen (LN) availability on their accumulation. Thirty-one phenolics from the four sub-classes, hydroxycinnamoyl esters, flavonoids, anthocyanins and phenolamides were identified, five of which had not previously been reported in these tomato organs. A higher diversity and concentration of phenolics was found in leaves than in stems and roots. The qualitative distribution of these compounds between plant organs was similar for the nine cultivars with the exception of Micro-Tom because of its significantly higher phenolic concentrations in leaves and stems as compared to roots. With few exceptions, the influence of the LN treatment on the three organs of all cultivars was to increase the concentrations of hydroxycinnamoyl esters, flavonoids and anthocyanins and to decrease those of phenolamides. This impact of LN was greater in roots than in leaves and stems. Nitrogen nutrition thus appears as a means of modulating the concentration and composition of organ phenolics and their distribution within the whole plant. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Atmospheric concentrations of ammonia and nitrogen dioxide at a tropical coral cay with high seabird density.

PubMed

Schmidt, Susanne; Mackintosh, Katrina; Gillett, Rob; Pudmenzky, Alex; Allen, Diane E; Rennenberg, Heinz; Mueller, Jochen F

2010-02-01

Ecosystems with high seabird densities can receive extremely high inputs of nitrogen (N) from bird guano. Seabirds deposit up to 1000 kg N ha(-1) y(-1) on Heron Island, a tropical coral cay of the Great Barrier Reef. We quantified atmospheric concentrations of ammonia (NH(3)) and nitrogen dioxide (NO(2)) with passive air samplers at beach, woodland and forest along a gradient of low, intermediate and high bird densities, respectively. NO(2) concentrations at all studied sites were generally low (average 0.2-2.3 microg NO(2) m(-3)) and similar to other ecosystems. An exception was the main traffic zone of helicopter and barge traffic which had elevated concentrations (average 6.2, maximum 25 microg NO(2) m(-3)) comparable to traffic-intense urban areas elsewhere. Increasing average NH(3) concentrations from 0.7 to 17 microg NH(3) m(-3) was associated with greater seabird nesting density. In areas of intermediate and high bird density, NH(3) concentrations were substantially higher than those typically detected in natural and agricultural systems, supporting the notion that seabird guano is a major source of NH(3). The steep decline of NH(3) concentrations in areas with low bird density indicates that trans-island transport of NH(3) is low. NH(3) may not only be re-deposited in close vicinity of the source but is also transported vertically as concentrations above the tree canopy averaged 7.5 microg NH(3) m(-3). How much guano-derived NH(3) contributes to reefal waters via the possible transfer path water --> land --> water remains to be established. We discuss atmospheric concentrations of NH(3) and NO(2) in context of N-based gaseous pollutants and effects on vegetation.

Experimental investigation on the performance, gaseous and particulate emissions of a methanol fumigated diesel engine.

PubMed

Cheng, C H; Cheung, C S; Chan, T L; Lee, S C; Yao, C D

2008-01-15

Experiments were conducted on a 4-cylinder direct-injection diesel engine with fumigation methanol injected into the air intake of each cylinder. The fumigation methanol was injected to top up 10%, 20% and 30% of the power output under different engine operating conditions. The effects of fumigation methanol on engine performance, gaseous emissions and particulate emission were investigated. The experimental results show that there is a decrease in the brake thermal efficiency when fumigation methanol is applied, except at the highest load of 0.67 MPa. At low loads, the brake thermal efficiency decreases with increase in fumigation methanol; but at high loads, it increases with increase in fumigation methanol. The fumigation method results in a significant increase in hydrocarbon (HC), carbon monoxide (CO), and nitrogen dioxide (NO(2)) emissions. The concentration of nitrogen oxides (NOx) is significantly reduced except at close to full load condition. There is also a reduction in the smoke opacity and the particulate matter (PM) mass concentration. For the submicron particles, the total number of particles decreases at low and medium loads but increases at high loads. In all cases, there is a shift of the particles towards smaller geometrical mean diameter, especially at high loads. The increase in nano-sized particles and the increase in NO(2) emission could have serious impact on human health.

Effects of Offshore Oil Exploration and Development in the Alaskan Beaufort Sea: A Three-Decade Record for Sediment Metals.

PubMed

Trefry, John H; Neff, Jerry M

2018-06-19

Impacts from oil exploration, development and production in the Beaufort Sea, Alaska, are assessed using concentrations of metals in sediments collected during 2014-15, combined with a large dataset for 1985-2006. Concentrations of 7 (1980 s) or 17 (1999-2015) metals in 423 surface sediments from 134 stations, plus 563 samples from 30 cores were highly variable, primarily as a function of sediment granulometry with naturally greater metal concentrations in fine-grained, Al-rich sediment. Metals versus Al correlation plots were used to normalize metal concentrations and identify values significantly above background. Barium, Cr, Cu, Hg and Pb concentrations were above background, but variable, within 250 m of some offshore sites where drilling occurred between 1981-2001; these areas totaled <6 km 2 of 11,000 km 2 in the total lease area. Random and fixed sampling along the coastal Beaufort Sea from 1985-2015 yielded 40 positive anomalies for metals in surface sediments (∼0.8% of 5,082 data points). About 85% of the anomalies were from developed areas. Half the anomalies were for the five metals found enhanced near drilling sites. No metals concentrations, except As, exceeded accepted sediment quality criteria. Interannual shifts in metals values for surface sediments at inner shelf sites were common and linked to storm-induced transitions in granulometry; however, metal/Al ratios were uniform during these shifts. Sediment cores generally recorded centuries of background values, except for As, Fe and Mn. These three metals were naturally enriched in sediments from deeper water (>100 m) via diagenetic remobilization at sediment depths of 5-15 cm, upward diffusion, and precipitation in surface oxic layers. Minimal evidence for anthropogenic inputs of metals, except near some exploratory drilling sites, is consistent with extraction of most oil from land or barrier islands in the Alaskan Arctic and restricted offshore activity to date. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Dietary fat induces sustained reward response in the human brain without primary taste cortex discrimination

PubMed Central

Tzieropoulos, Hélène; Rytz, Andreas; Hudry, Julie; le Coutre, Johannes

2013-01-01

To disentangle taste from reward responses in the human gustatory cortex, we combined high density electro-encephalography with a gustometer delivering tastant puffs to the tip of the tongue. Stimuli were pure tastants (salt solutions at two concentrations), caloric emulsions (two milk preparations identical in composition except for fat content) and a mixture of high fat milk with the lowest salt concentration. Early event-related potentials (ERPs) showed a dose-response effect for increased taste intensity, with higher amplitude and shorter latency for high compared to low salt concentration, but not for increased fat content. However, the amplitude and distribution of late potentials were modulated by fat content independently of reported intensity and discrimination. Neural source estimation revealed a sustained activation of reward areas to the two high-fat stimuli. The results suggest calorie detection through specific sensors on the tongue independent of perceived taste. Finally, amplitude variation of the first peak in the event-related potential to the different stimuli correlated with papilla density, suggesting a higher discrimination power for subjects with more fungiform papillae. PMID:23430280

Carbon export and cycling by the Yukon, Tanana, and Porcupine rivers, Alaska, 2001-2005

USGS Publications Warehouse

Striegl, Robert G.; Dornblaser, Mark M.; Aiken, George R.; Wickland, Kimberly P.; Raymond, Peter A.

2007-01-01

Loads and yields of dissolved and particulate organic and inorganic carbon (DOC, POC, DIC, PIC) were measured and modeled at three locations on the Yukon River (YR) and on the Tanana and Porcupine rivers (TR, PR) in Alaska during 2001–2005. Total YR carbon export averaged 7.8 Tg C yr−1, 30% as OC and 70% as IC. Total C yields (0.39–1.03 mol C m−2 yr−1) were proportional to water yields (139–356 mm yr−1; r2 = 0.84) at all locations. Summer DOC had an aged component (fraction modern (FM) = 0.94–0.97), except in the permafrost wetland‐dominated PR, where DOC was modern. POC had FM = 0.63–0.70. DOC had high concentration, high aromaticity, and high hydrophobic content in spring and low concentration, low aromaticity, and high hydrophilic content in winter. About half of annual DOC export occurred during spring. DIC concentration and isotopic composition were strongly affected by dissolution of suspended carbonates in glacial meltwater during summer.

Stability of ondansetron hydrochloride injection in various beverages.

PubMed

Yamreudeewong, W; Danthi, S N; Hill, R A; Fox, J L

1995-09-15

The stability of ondansetron hydrochloride injection in beverages likely to be acceptable to patients was studied. Ondansetron hydrochloride injection (containing ondansetron 2 mg/mL) was added to apple juice, fruit punch, cherry-flavored drink, carbonated soft drinks, and hot tea to provide a nominal ondansetron concentration of 32.8, 64.5, or 95.2 micrograms/mL. Samples were stored at -3 to 28 degrees C (noncarbonated-beverage mixtures except tea), 2 to 28 degrees C (carbonated-beverage mixtures), and 25 degrees C (tea) and assayed for ondansetron concentration by high-performance liquid chromatography at 6, 24, 48, and 72 hours (noncarbonated-beverage mixtures except tea); 6, 24, and 48 hours (carbonated-beverage mixtures); and 1 hour (tea). More than 95% of the initial ondansetron concentration was retained in apple juice, fruit punch, cherry-flavored drink, Sprite, and Diet Coke throughout the periods studied. A precipitate formed immediately after ondansetron was added to hot tea, but the drug was chemically stable for at least one hour in this preparation. Ondansetron hydrochloride injection 32.7, 64.5, and 95.2 micrograms/mL (expressed as free base) was stable in various beverages when stored at -3 to 28 degrees C for up to 72 hours. Ondansetron at these same concentrations precipitated in hot tea preparations but was chemically stable for at least one hour.

Polychlorinated biphenyl concentrations in Hudson River water and treated drinking water at Waterford, New York

USGS Publications Warehouse

Schroeder, R.A.; Barnes, C.R.

1983-01-01

Past discharge of PCBs into the Hudson River has resulted in contaminant concentrations of a few tenths of a microgram per liter in the water. Waterford is one of two large municipal users of the Hudson River for drinking-water supply. The treatment scheme at the Waterford plant, which processes approximately 1 million gallons per day, is similar to that of most conventional treatment plants except for the addition of powdered activated carbon during flocculation. Comparison of PCB concentrations in river water and intake water at the plant to concentrations in treated drinking-water samples indicates that purification processes remove 80 to 90 percent of the PCBs and that final concentrations seldom exceed 0.1 microgram per liter. No significant difference was noted between the removal efficiencies during periods of high river discharge, when PCBs are associated with suspended sediment, and low discharge, when PCBs are generally dissolved. (USGS)

Flavor-Intensity Perception: Effects of Stimulus Context

PubMed Central

Marks, Lawrence E.; Shepard, Timothy G.; Burger, Kelly; Chakwin, Emily M.

2011-01-01

Stimulus context affects judgments of intensity of both gustatory and olfactory flavors, and the contextual effects are modality-specific. Does context also exert separate effects on the gustatory and olfactory components of flavor mixtures? To answer this question, in each of 4 experiments, subjects rated the perceived intensity of 16 mixtures constructed by combining 4 concentrations of the gustatory flavorant sucrose with 4 concentrations of the retronasal olfactory flavorant citral. In 1 contextual condition of each experiment, concentrations of sucrose were relatively high and those of citral low; in the other condition, the relative concentrations of sucrose and citral reversed. There were 2 main results: First, consistent with earlier findings, in 5 of the 8 conditions, the ratings were consistent with linear addition of perceived sucrose and citral; departures from additivity appeared, however, in 3 conditions where the relative concentrations of citral were high. Second, changes in context produced contrast (adaptation-like changes) in perceived intensity: The contribution to perceived intensity of a given concentration of a flavorant was smaller when the contextual concentrations of that flavorant were high rather than low. A notable exception was the absence of contextual effects on the perceived intensity of near-threshold citral. These findings suggest that the contextual effects may arise separately in the gustatory and olfactory channels, prior to the integration of perceived flavor intensity. PMID:21930139

Concentrations of Selected Elements in Liver Tissue of Grey Wolves (Canis lupus) from Serbia.

PubMed

Subotić, Srđan; Višnjić-Jeftić, Željka; Penezić, Aleksandra; Ćirović, Duško

2017-12-01

The grey wolf (Canis lupus) is a large carnivore species and a top predator in the ecosystems that it inhabits. Considering its role in food webs, wolves may be exposed to high concentrations of potentially harmful elements. Therefore liver samples from 28 legally hunted wolves were analyzed for concentrations of 16 elements using inductively coupled plasma optical emission spectrometry. The Mann-Whitney U test showed a significant difference between the genders only for Li, and there were no differences between individuals caught in different years. The majority of statistically significant correlations between element levels were positive, except for three cases. Compliance with several criteria for suitable bioindicator organisms imply that wolves may serve for monitoring environmental contamination.

Distribution of heavy metals in agricultural soils near a petrochemical complex in Guangzhou, China.

PubMed

Li, Junhui; Lu, Ying; Yin, Wei; Gan, Haihua; Zhang, Chao; Deng, Xianglian; Lian, Jin

2009-06-01

The aim of the study was to investigate influence of an industrialized environment on the accumulation of heavy metals in agricultural soils. Seventy soil samples collected from surface layers (0-20 cm) and horizons of five selected pedons in the vicinity area of petrochemical complex in Guangzhou, China were analyzed for Zn, Cu, Pb, Cd, Hg and As concentrations, the horizontal and vertical variation of these metals were studied and geographic information system (GIS)-based mapping techniques were applied to generate spatial distribution maps. The mean concentrations of these heavy metals in the topsoils did not exceed the maximum allowable concentrations in agricultural soil of China with the exception of Hg. Significant differences between land-use types showed that Cu, Pb, Cd, Hg and As concentrations in topsoils were strongly influenced by agricultural practices and soil management. Within a radius of 1,300 m there were no marked decreasing trends for these element concentrations (except for Zn) with the increase of distance from the complex boundary, which reflected little influence of petroleum air emission on soil heavy metal accumulation. Concentrations of Zn, Cu, Pb, Cd, Hg and As in the five pedons, particularly in cultivated vegetable field and orchard, decreased with soil depth, indicating these elements mainly originated from anthropogenic sources. GIS mapping was a useful tool for evaluating spatial variability of heavy metals in the affected soil. The spatial distribution maps allowed the identification of hot-spot areas with high metal concentration. Effective measures should be taken to avoid or minimize heavy metal further contamination of soils and to remediate the contaminated areas in order to prevent pollutants affecting human health through agricultural products.

Endogenous flow of amino acids in the avian ileum as influenced by increasing dietary peptide concentrations.

PubMed

Ravindran, Velmurugu; Morel, Patrick C H; Rutherfurd, Shane M; Thomas, Donald V

2009-03-01

The aim of the present study was to establish whether feeding broiler chickens with diets containing increasing dietary peptide concentrations would cause increases in ileal endogenous amino acid flow. The flow of N and most amino acids increased quadratically (P < 0.05 to 0.001) with increasing dietary concentrations of peptides. The exceptions were the flow of threonine, serine, glycine, tyrosine and cystine, which increased linearly (P < 0.001) with dietary peptide levels. Another notable exception to the general trend was the flow of proline, which was significantly higher (P < 0.01) in birds fed the protein-free diet. The amino acid profile of endogenous protein, expressed as proportion of crude protein, indicated that the ratios of threonine, glutamic acid, proline, glycine, leucine, histidine, arginine and cystine were influenced (P < 0.05) with increasing dietary peptide concentrations. In general, compared with the protein-free diet, the ratios of threonine and arginine in endogenous protein were lower (P < 0.05) and those of glutamic acid, glycine and histidine were greater (P < 0.05) in diets with high concentrations of peptides. The ratio of proline was found to decrease (P < 0.05) with increasing dietary peptide concentrations. These changes in the amino acid profile of endogenous protein are probably reflective of changes in the output of one or more of the components of endogenous protein. Overall, the present results demonstrated that increasing dietary peptide concentrations increased the flow of endogenous amino acid flow at the terminal ileum of broiler chickens in a dose-dependent manner and also caused changes in the composition of endogenous protein. The observed changes in endogenous amino flow will influence the maintenance requirements for amino acids and also have implications for the calculation of true digestibility coefficient of feedstuffs.

Influence of counting chamber type on CASA outcomes of equine semen analysis.

PubMed

Hoogewijs, M K; de Vliegher, S P; Govaere, J L; de Schauwer, C; de Kruif, A; van Soom, A

2012-09-01

Sperm motility is considered to be one of the key features of semen analysis. Assessment of motility is frequently performed using computer-assisted sperm analysis (CASA). Nevertheless, no uniform standards are present to analyse a semen sample using CASA. We hypothesised that the type of counting chamber used might influence the results of analysis and aimed to study the effect of chamber type on estimated concentration and motility of an equine semen sample assessed using CASA. Commonly used disposable Leja chambers of different depths were compared with disposable and reusable ISAS chambers, a Makler chamber and a World Health Organization (WHO) motility slide. Motility parameters and concentrations obtained with CASA using these different chambers were analysed. The NucleoCounter was used as gold standard for determining concentration. Concentration and motility parameters were significantly influenced by the chamber type used. Using the NucleoCounter as the gold standard for determining concentration, the correlation coefficients were low for all of the various chambers evaluated, with the exception of the 12 µm deep Leja chamber. Filling a chamber by capillary forces resulted in a lower observed concentration and reduced motility parameters. All chambers evaluated in this study resulted in significant lower progressive motility than the WHO prepared slide, with the exception of the Makler chamber, which resulted in a slight, but statistically significant, increase in progressive motility estimates. Computer-assisted sperm analysis can only provide a rough estimate of sperm concentration and overestimation is likely when drop-filled slides with a coverslip are used. Motility estimates using CASA are highly influenced by the counting chamber; therefore, a complete description of the chamber type used should be provided in semen reports and in scientific articles. © 2011 EVJ Ltd.

Fault detection and isolation of high temperature proton exchange membrane fuel cell stack under the influence of degradation

NASA Astrophysics Data System (ADS)

Jeppesen, Christian; Araya, Samuel Simon; Sahlin, Simon Lennart; Thomas, Sobi; Andreasen, Søren Juhl; Kær, Søren Knudsen

2017-08-01

This study proposes a data-drive impedance-based methodology for fault detection and isolation of low and high cathode stoichiometry, high CO concentration in the anode gas, high methanol vapour concentrations in the anode gas and low anode stoichiometry, for high temperature PEM fuel cells. The fault detection and isolation algorithm is based on an artificial neural network classifier, which uses three extracted features as input. Two of the proposed features are based on angles in the impedance spectrum, and are therefore relative to specific points, and shown to be independent of degradation, contrary to other available feature extraction methods in the literature. The experimental data is based on a 35 day experiment, where 2010 unique electrochemical impedance spectroscopy measurements were recorded. The test of the algorithm resulted in a good detectability of the faults, except for high methanol vapour concentration in the anode gas fault, which was found to be difficult to distinguish from a normal operational data. The achieved accuracy for faults related to CO pollution, anode- and cathode stoichiometry is 100% success rate. Overall global accuracy on the test data is 94.6%.

Pollution characteristics, risk assessment, and source apportionment of heavy metals in road dust in Beijing, China.

PubMed

Men, Cong; Liu, Ruimin; Xu, Fei; Wang, Qingrui; Guo, Lijia; Shen, Zhenyao

2018-01-15

To analyze the spatial distribution patterns, risks, and sources of heavy metals (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn, Fe), 36 road dust samples were collected from an urbanized area of Beijing in June 2016. The mean concentration of most metals, except As and Mn, exceeded their corresponding background values, with the mean concentration of Cd being 8 times that of its background. Spatially, for most heavy metals, except As and Mn, the high concentration areas were mainly within the 5th ring road, especially the northern area. The geo-accumulation index of Cd and Cu indicated moderate contamination at many sites. The entire study area was prone to potential ecological risks, with higher risks within the 4th ring road. Cd caused high potential ecological risk at most sites. According to the health risk assessment results, the non-carcinogenic risks that human beings suffered from heavy metals were insignificant. However, the carcinogenic risks due to Ni and Cr exceeded the acceptable level. Based on the source apportionment using positive matrix factorization, four factors were defined for the heavy metals. Factor 1, which was traffic-related exhaust, accounted for 34.47% of the concentration of heavy metals. The contributions of Factors 2 and 3 were approximately 25% each. Factor 2 was potentially related to coal combustion, while Factor 3 could be related to the manufacture and use of metal components. Factor 4, which could be related to the use of pesticides, fertilizers, and medical devices, accounted for 14.88%, which was the lowest. Copyright © 2017 Elsevier B.V. All rights reserved.

Novel aplanatic designs for LED concentration

NASA Astrophysics Data System (ADS)

Ricketts, Melissa; Winston, Roland; Jiang, Lun

2014-09-01

Aplanats make great concentrators because of their near perfect imaging. Aplanatic conditions can be satisfied using two surface curves (generally mirrored surfaces) in two dimensions (see Figure 1) which are constructed by successive approximation to create a highly efficient concentrator for both concentration and illumination. For concentration purposes, having a two mirror system would be impossible because the front mirror would block incoming light (see figure 2) so the idea is to replace the front mirror with a "one-way" mirror. Light from a lower index can be transmitted, so if the aplanat surface is a higher index light is allowed to enter, and be trapped. In the Jellyfish design, TIR takes place except for light striking the surface within the range of critical angles. To combat that, a small area of reflective coating is applied to the central top part of the Jellyfish, where TIR fails (In the middle) to keep the light there from directly escaping (see figure 3). The design works in both forwards and reverse. Light entering can be focused to a collecter, or the collecter can be replaced with a light source to concentrate light out. In this case, LEDs are used for their highly efficienct properties.

21 CFR 169.178 - Concentrated vanilla flavoring.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Concentrated vanilla flavoring. 169.178 Section... Food Dressings and Flavorings § 169.178 Concentrated vanilla flavoring. (a) Concentrated vanilla... statement of ingredients prescribed for vanilla flavoring by § 169.177, except that it is concentrated to...

21 CFR 169.178 - Concentrated vanilla flavoring.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Concentrated vanilla flavoring. 169.178 Section... Food Dressings and Flavorings § 169.178 Concentrated vanilla flavoring. (a) Concentrated vanilla... statement of ingredients prescribed for vanilla flavoring by § 169.177, except that it is concentrated to...

21 CFR 169.178 - Concentrated vanilla flavoring.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Concentrated vanilla flavoring. 169.178 Section... Food Dressings and Flavorings § 169.178 Concentrated vanilla flavoring. (a) Concentrated vanilla... statement of ingredients prescribed for vanilla flavoring by § 169.177, except that it is concentrated to...

21 CFR 169.178 - Concentrated vanilla flavoring.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Concentrated vanilla flavoring. 169.178 Section... Food Dressings and Flavorings § 169.178 Concentrated vanilla flavoring. (a) Concentrated vanilla... statement of ingredients prescribed for vanilla flavoring by § 169.177, except that it is concentrated to...

21 CFR 169.178 - Concentrated vanilla flavoring.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Concentrated vanilla flavoring. 169.178 Section... Food Dressings and Flavorings § 169.178 Concentrated vanilla flavoring. (a) Concentrated vanilla... statement of ingredients prescribed for vanilla flavoring by § 169.177, except that it is concentrated to...

New study on the correlation between carbon dioxide concentration in the environment and radon monitor devices.

PubMed

Shahrokhi, A; Burghele, B D; Fábián, F; Kovács, T

2015-12-01

The influence of high geogenic carbon dioxide concentrations on monitoring devices might present a significant challenge to the measurement of radon concentrations in environments with a high level of carbon dioxide concentration such as volcano sites, mofettes, caves, etc. In this study, the influence of carbon dioxide concentration on several different types of radon monitor devices - including Alpha Spectrometry (Sarad RTM 2200, EQF 3220, RAD7), Ionizing Chamber (AlphaGUARD PQ2000 PRO) and Active Cell (Active scintillation cell, Pylon 300A) - was examined to represent new aspects of radon measuring in environments with carbon dioxide. In light of the results, all measuring devices were exposed to variable conditions affected by carbon dioxide concentration, except for the AlphaGUARD, which was kept in a steady state throughout the experiment. It was observed that alpha spectroscopy devices were affected by carbon dioxide, since measured radon concentrations decreased in the presence of 70% and 90% carbon dioxide concentrations by 26.5 ± 2% and 14.5 ± 2.5% for EQF 3220, and 32 ± 2% and 35.5 ± 2% for RTM 2200. However, the ionizing chamber instrument was unaffected by changes in carbon dioxide concentration. It was determined that the RAD7 performed relatively inefficiently in the presence of carbon dioxide concentrations higher than 67% by an overall efficiency factor of approximately 0.52, confirming that it is not an admissible radon monitor instrument in environments with high carbon dioxide concentrations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cardiometabolic risk factors are associated with high urinary enterolactone concentration, independent of urinary enterodiol concentration and dietary fiber intake in adults.

PubMed

Frankenfeld, Cara L

2014-09-01

The study objective was to evaluate independent and interactive associations of dietary fiber intake and high urinary enterolignans with cardiometabolic risk factors. The analysis included 2260 adults (≥20 y of age) from the 2003-2010 NHANES. Logistic regression models were used to evaluate obesity and clinically defined cardiometabolic risk factors in relation to dietary fiber intake and urinary enterolignan concentrations. Three sets of models were created: 1) independent associations, 2) mutually adjusted associations, and 3) interactions. Models were adjusted for age, gender, race/ethnicity, education, smoking status, and energy intake. High concentrations were considered to be above the 90th percentile of urinary enterolignan concentrations. Increasing dietary fiber intake was associated with high blood pressure (P = 0.02) and low serum HDL cholesterol (P-trend = 0.03). High urinary enterodiol concentration was not associated with obesity or cardiometabolic risk factors. High urinary enterolactone concentration was inversely associated with obesity (OR: 0.44; 95% CI: 0.29, 0.66), abdominal obesity (OR: 0.58; 95% CI: 0.39, 0.87), high serum C-reactive protein (CRP; OR: 0.52; 95% CI: 0.37, 0.74), high serum triglycerides (OR: 0.39; 95% CI: 0.23, 0.61), low serum HDL cholesterol (OR: 0.37; 95% CI: 0.23, 0.61), and metabolic syndrome (OR: 0.47; 95% CI: 0.30, 0.74). In mutually adjusted models, enterolactone associations observed in independent models remained similar, but associations for dietary fiber intake were attenuated, with the exception of blood pressure. In interaction models, there were 2 significant interactions: between high urinary enterodiol concentration and dietary fiber intake for high serum CRP (P = 0.04) and high plasma glucose (P = 0.04). Overall, being in the highest 10% of urinary enterolactone concentration was associated with cardiometabolic risk factors, independent of dietary fiber intake and enterodiol concentration. Future studies are warranted to evaluate physiologic actions of enterolactone or aspects of the gut microbial profile responsible for lignan metabolism to enterolactone. © 2014 American Society for Nutrition.

Selected ground-water-quality data of the Lockport Dolomite in Darke, Miami, Montgomery, and Preble Counties, Ohio

USGS Publications Warehouse

Dumouchelle, D.H.

1999-01-01

In 1998, 25 samples of ground water from the Lockport Dolomite in western Ohio were analyzed for major ions, trace elements, and arsenic. Samples were collected from residential wells in Darke, Miami, Montgomery, and Preble Counties. The water sampled was untreated, except perhaps for water from one well. In general, samples from the northern part of the study area had the highest concentrations of common constituents such as calcium, magnesium, potassium, sulfate, boron, and strontium. Iron and strontium concentrations were generally high throughout the study area, with median concentrations of 4,500 ?g/L (micrograms per liter) and 1,500 ?g/L, respectively. Arsenic concentrations, which ranged from less than 1 ?g/L to 29 ?g/L, did not exceed the drink ing-water standard of 50 ?g/L.

Ambient air pollution and cancer in California Seventh-day Adventists.

PubMed

Mills, P K; Abbey, D; Beeson, W L; Petersen, F

1991-01-01

Cancer incidence and mortality in a cohort of 6,000 Seventh-day Adventist nonsmokers who were residents of California were monitored for a 6-y period, and relationships with long-term ambient concentrations of total suspended particulates (TSPs) and ozone (O3) were studied. Ambient concentrations were expressed as mean concentrations and exceedance frequencies, which are the number of hours during which concentrations exceeded specified cutoffs (e.g., federal and California air quality standards). Risk of malignant neoplasms in females increased concurrently with exceedance frequencies for all TSP cutoffs, except the lowest, and these increased risks were highly statistically significant. An increased risk of respiratory cancers was associated with only one cutoff of O3, and this result was of borderline significance. These results are presented in the context of setting standards for these two air pollutants.

Chemical characteristics of urban stormwater sediments and implications for environmental management, Maricopa County, Arizona

USGS Publications Warehouse

Parker, J.T.C.; Fossum, K.D.; Ingersoll, T.L.

2000-01-01

Investigations of the chemical characteristics of urban stormwater sediments in the rapidly growing Phoenix metropolitan area of Maricopa County, Arizona, showed that the inorganic component of these sediments generally reflects geologic background values. Some concentrations of metals were above background values, especially cadmium, copper, lead, and zinc, indicating an anthropogenic contribution of these elements to the sediment chemistry. Concentrations, however, were not at levels that would require soil remediation according to guidelines of the U.S. Environmental Protection Agency. Arsenic concentrations generally were above recommended values for remediation at a few sites, but these concentrations seem to reflect geologic rather than anthropogenic factors. Several organochlorine compounds no longer in use were ubiquitous in the Phoenix area, although concentrations generally were low. Chlordane, DDT and its decay products DDE and DDD, dieldrin, toxaphene, and PCBs were found at almost all sites sampled, although some of the pesticides in which these compounds are found have been banned for almost 30 years. A few sites showed exceptionally high concentrations of organochlorine compounds. On the basis of published guidelines, urban stormwater sediments do not appear to constitute a major regional environmental problem with respect to the chemical characteristics investigated here. At individual sites, high concentrations of organic compounds - chlordane, dieldrin, PCBs, and toxaphene - may require some attention. The possible environmental hazard presented by low-level organochlorine contamination is not addressed in this paper; however, high levels of toxicity in urban sediments are difficult to explain. Sediment toxicity varied significantly with time, which indicates that these tests should be evaluated carefully before they are used for management decisions.Investigations of the chemical characteristics of urban stormwater sediments in the rapidly growing Phoenix metropolitan area of Maricopa County, Arizona, showed that the inorganic component of these sediments generally reflects geologic background values. Some concentrations of metals were above background values, especially cadmium, copper, lead, and zinc, indicating an anthropogenic contribution of these elements to the sediment chemistry. Concentrations, however, were not at levels that would require soil remediation according to guidelines of the U.S. Environmental Protection Agency. Arsenic concentrations generally were above recommended values for remediation at a few sites, but these concentrations seem to reflect geologic rather than anthropogenic factors. Several organochlorine compounds no longer in use were ubiquitous in the Phoenix area, although concentrations generally were low. Chlordane, DDT and its decay products DDE and DDD, dieldrin, toxaphene, and PCBs were found at almost all sites sampled, although some of the pesticides in which these compounds are found have been banned for almost 30 years. A few sites showed exceptionally high concentrations of organochlorine compounds. On the basis of published guidelines, urban stormwater sediments do not appear to constitute a major regional environmental problem with respect to the chemical characteristics investigated here. At individual sites, high concentrations of organic compounds - chlordane, dieldrin, PCBs, and toxaphene - may require some attention. The possible environmental hazard presented by low-level organochlorine contamination is not addressed in this paper; however, high levels of toxicity in urban sediments are difficult to explain. Sediment toxicity varied significantly with time, which indicates that these tests should be evaluated carefully before they are used for management decisions.

Change of heavy metal speciation, mobility, bioavailability, and ecological risk during potassium ferrate treatment of waste-activated sludge.

PubMed

Yu, Ming; Zhang, Jian; Tian, Yu

2018-05-01

The effects of potassium ferrate treatment on the heavy metal concentrations, speciation, mobility, bioavailability, and environmental risk in waste-activated sludge (WAS) at various dosages of potassium ferrate and different treatment times were investigated. Results showed that the total concentrations of all metals (except Cd) were decreased slightly after treatment and the order of metal concentrations in WAS and treated waste-activated sludge (TWAS) was Mg > Zn > Cu > Cr > Pb > Ni > Cd. Most heavy metals in WAS remained in TWAS after potassium ferrate treatment with metal residual rates over 67.8% in TWAS. The distribution of metal speciation in WAS was affected by potassium ferrate treatment. The bioavailability and the mobility of heavy metals (except Mg) in TWAS were mitigated, compared to those in WAS. Meanwhile, the environmental risk of heavy metals (except Pb and Cu) was alleviated after potassium ferrate treatment.

Influence of extractable soil manganese on oxidation capacity of different soils in Korea

NASA Astrophysics Data System (ADS)

Chon, Chul-Min; Kim, Jae Gon; Lee, Gyoo Ho; Kim, Tack Hyun

2008-08-01

We examined the relationship between soil oxidation capacity and extractable soil manganese, iron oxides, and other soil properties. The Korean soils examined in this study exhibited low to medium Cr oxidation capacities, oxidizing 0.00-0.47 mmol/kg, except for TG-4 soils, which had the highest capacity for oxidizing added Cr(III) [>1.01 mmol/kg of oxidized Cr(VI)]. TG and US soils, with high Mn contents, had relatively high oxidation capacities. The Mn amounts extracted by dithionite-citrate-bicarbonate (DCB) (Mnd), NH2OH·HCl (Mnh), and hydroquinone (Mnr) were generally very similar, except for the YS1 soils, and were well correlated. Only small proportions of either total Mn or DCB-extractable Mn were extracted by NH2OH·HCl and hydroquinone in the YS1 soils, suggesting inclusion of NH2OH·HCl and hydroquinone-resistant Mn oxides, because these extractants are weaker reductants than DCB. No Cr oxidation test results were closely related to total Mn concentrations, but Mnd, Mnh, and Mnr showed a relatively high correlation with the Cr tests ( r = 0.655-0.851; P < 0.01). The concentrations of Mnd and Mnh were better correlated with the Cr oxidation tests than was the Mnr concentration, suggesting that the oxidation capacity of our soil samples can be better explained by Mnd and Mnh than by Mnr. The first component in principal components analysis indicated that extractable soil Mn was a main factor controlling net Cr oxidation in the soils. Total soil Mn, Fe oxides, and the clay fraction are crucial for predicting the mobility of pollutants and heavy metals in soils. The second principal component indicated that the presence of Fe oxides in soils had a significant relationship with the clay fraction and total Mn oxide, and was also related to heavy-metal concentrations (Zn, Cd, and Cu, but not Pb).

21 CFR 169.176 - Concentrated vanilla extract.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Concentrated vanilla extract. 169.176 Section 169... Dressings and Flavorings § 169.176 Concentrated vanilla extract. (a) Concentrated vanilla extract conforms... ingredients prescribed for vanilla extract by § 169.175, except that it is concentrated to remove part of the...

21 CFR 169.176 - Concentrated vanilla extract.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Concentrated vanilla extract. 169.176 Section 169... Dressings and Flavorings § 169.176 Concentrated vanilla extract. (a) Concentrated vanilla extract conforms... ingredients prescribed for vanilla extract by § 169.175, except that it is concentrated to remove part of the...

21 CFR 169.176 - Concentrated vanilla extract.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Concentrated vanilla extract. 169.176 Section 169... Dressings and Flavorings § 169.176 Concentrated vanilla extract. (a) Concentrated vanilla extract conforms... ingredients prescribed for vanilla extract by § 169.175, except that it is concentrated to remove part of the...

21 CFR 169.176 - Concentrated vanilla extract.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Concentrated vanilla extract. 169.176 Section 169... Dressings and Flavorings § 169.176 Concentrated vanilla extract. (a) Concentrated vanilla extract conforms... ingredients prescribed for vanilla extract by § 169.175, except that it is concentrated to remove part of the...

21 CFR 169.176 - Concentrated vanilla extract.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Concentrated vanilla extract. 169.176 Section 169... Dressings and Flavorings § 169.176 Concentrated vanilla extract. (a) Concentrated vanilla extract conforms... ingredients prescribed for vanilla extract by § 169.175, except that it is concentrated to remove part of the...

A single-blind controlled study of electrocautery and ultrasonic scalpel smoke plumes in laparoscopic surgery.

PubMed

Fitzgerald, J Edward F; Malik, Momin; Ahmed, Irfan

2012-02-01

Surgical smoke containing potentially carcinogenic and irritant chemicals is an inevitable consequence of intraoperative energized dissection. Different energized dissection methods have not been compared directly in human laparoscopic surgery or against commonly encountered pollutants. This study undertook an analysis of carcinogenic and irritant volatile hydrocarbon concentrations in electrocautery and ultrasonic scalpel plumes compared with cigarette smoke and urban city air control samples. Once ethical approval was obtained, gas samples were aspirated from the peritoneal cavity after human laparoscopic intraabdominal surgery solely using either electrocautery or ultrasonic scalpels. All were adsorbed in Tenax tubes and concentrations of carcinogenic or irritant volatile hydrocarbons measured by gas chromatography. The results were compared with cigarette smoke and urban city air control samples. The analyzing laboratory was blinded to sample origin. A total of 10 patients consented to intraoperative gas sampling in which only one method of energized dissection was used. Six carcinogenic or irritant hydrocarbons (benzene, ethylbenzene, styrene, toluene, heptene, and methylpropene) were identified in one or more samples. With the exception of styrene (P = 0.016), a nonsignificant trend toward lower hydrocarbon concentrations was observed with ultrasonic scalpel use. Ultrasonic scalpel plumes had significantly lower hydrocarbon concentrations than cigarette smoke, with the exception of methylpropene (P = 0.332). No significant difference was observed with city air. Electrocautery samples contained significantly lower hydrocarbon concentrations than cigarette smoke, with the exception of toluene (P = 0.117) and methyl propene (P = 0.914). Except for toluene (P = 0.028), city air showed no significant difference. Both electrocautery and ultrasonic dissection are associated with significantly lower concentrations of the most commonly detected carcinogenic and irritant hydrocarbons than cigarette smoke. A nonsignificant trend toward lower hydrocarbon concentrations was seen with ultrasonic scalpel dissection compared with diathermy. The contamination levels in city air were largely comparable with those seen after ultrasonic scalpel use. Although hydrocarbon concentrations are low, cumulative exposures may increase health risks. Where concerns arise, ultrasonic scalpel dissection may be preferable.

Effects of different peracetic acid formulations on post space radicular dentin.

PubMed

Belizário, Lauriê Garcia; Kuga, Milton Carlos; Castro-Núñez, Gabriela Mariana; Escalante-Otárola, Wilfredo Gustavo; Só, Marcus Vinicius Reis; Pereira, Jefferson Ricardo

2018-01-05

The optimal irrigating solution with antimicrobial and dentin cleansing properties for post space preparation for fiber posts is unclear. Peracetic acid is one option but is available in various chemical formulations that require evaluation. The purpose of this in vitro study was to evaluate dentin surface cleanliness based on the presence of a smear layer and the number of open dentin tubules. It also investigates the chemical composition of residues after canal irrigation with a 1% peracetic acid solution (PA) at low or high concentration of hydrogen peroxide during the preparation of intracanal fiber posts. After filling the root canals of 40 mandibular incisors, a rotary instrument was used for intracanal preparation to place fiber posts. The teeth were divided into 4 groups (n=10) according to the post space irrigation protocol as follows: CG (control): distilled water; NA (NaOCl): 2.5% sodium hypochlorite; LH: PA with low concentration of hydrogen peroxide; and HH: PA with high concentrations of hydrogen peroxide. After irrigation, the teeth were sectioned, and the intracanal dentin surface was subjected to analysis using energy dispersive spectroscopy to evaluate chemical composition and to scanning electron microscopy (×500) to evaluate the presence of the smear layer. The number of open dentin tubules was measured by scanning electron microscopy analysis (×2000) using photo-editing software. ANOVA and the Tukey test (α=.05) were used to evaluate the data, except for the presence of a smear layer, for which the Kruskal-Wallis and Dunn tests were used (α=.05). The highest concentrations of oxygen in the dentin residues were detected in LH and HH (P<.05); CG and NA showed similar oxygen concentrations (P>.05). NA had a higher concentration of chlorine (P<.05), whereas LH had a lower amount of smear layer and a larger number of open dentin tubules than the other groups (P<.05). These were equivalent to each other (P>.05), except for HH, which also had a larger number of open dentin tubules than CG and NA (P<.05). PA 1% with a low concentration of hydrogen peroxide yielded a lower amount of smear layer and a larger number of open dentin tubules in the dentin of the post space when compared with PA 1% with a high concentration of hydrogen peroxide, despite maintaining a similar oxygen concentration in these dentin residues. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Evaluation of cytotoxicity of some common ophthalmic drugs.

PubMed

Li, M; Chen, X-M; Liu, J-J; Wang, D-M; Gan, L; Lv, X; Qiao, Y

2015-01-01

The study was aimed at evaluating the in vitro cytotoxicity of some commonly used drugs in ophthalmology. Hydrocortisone sodium succinate, Dexamethasone sodium phosphate, 5-Fluorouracil, Tobramycin and Pilocarpine nitrate are frequently used in various indications involving eye care, and the aim was to test the safety of these in cell culture. The in vitro cytotoxicity was carried out on the NIH 3T3 cell line by the Sulforhodamine B (SRB) assay. With the exception of 5-Fluorouracil, none of the other drugs demonstrated appreciable cytotoxicity up to high concentrations of 200 µg/ml at 48 hours of drug exposure. Hydrocortisone sodium succinate, Dexamethasone sodium phosphate, Tobramycin and Pilocarpine nitrate were confirmed to be non-cytotoxic while 5-Fluorouracil was highly cytotoxic especially at 48 hours at very low concentrations.

Investigation of acidity and other water-quality characteristics of Upper Oyster Creek, Ocean County, New Jersey

USGS Publications Warehouse

Fusillo, Thomas V.; Schornick, J.C.; Koester, H.E.; Harriman, D.A.

1980-01-01

Water-quality data collected in the upper Oyster Creek drainage basin, Ocean County, N.J., indicate that the stream has excellent water quality except for a persistently low pH. The mean concentrations of the major inorganic ions were all less than 6.0 milligrams per liter. Mean concentrations of total nitrogen and total phosphorus were 0.15 mg/L and 0.01 mg/L, respectively. Dissolved oxygen averaged 8.7 mg/L and 81% saturation. Low pH levels are typical of streams draining cedar swamps. In Oyster Creek, the pH tended to decrease downstream due to chemical and biological processes. The pH levels in swamps were one-half unit or more lower than the pH levels in the adjacent stream. Sharp declines in stream pH were noted during runoff periods as the result of the mixing of poorly-buffered stream water with more highly acidic water from surrounding swamp areas. The quality of ground water within the study area was similar to the quality of streamflow, except for higher iron and ammonia-nitrogen concentrations and a higher pH range of 4.9 to 6.5. Precipitation represented a major source of many chemical constituents in the ground- and surface-waters of the Oyster Creek basin. (USGS)

Polycyclic aromatic hydrocarbons (PAHs) in yogurt samples.

PubMed

Battisti, Chiara; Girelli, Anna Maria; Tarola, Anna Maria

2015-01-01

The concentrations and distributions of major polycyclic aromatic hydrocarbons (PAHs) were determined in 20 kinds of yogurt specimens collected from Italian supermarkets using reversed phase high-performance liquid chromatography equipped with fluorescence detection. The method was validated by determination of recovery percentages, precision (repeatability) and sensitivity (limits of detection) with yogurt samples fortified at 0.25, 0.5 and 1 µg/kg concentration levels. The recovery of 13 PAHs, with the exception of naphthalene and acenaphthene, ranged from 61% to 130% and from 60% to 97% at all the levels for yogurts with low (0.1%) and high (3.9%) fat content, respectively. The method is repeatable with relative standard deviation values <20% for all analytes. The results obtained demonstrate that acenaphthene, fluorantene, phenanthrene, anthracene, fluoranthene and pyrene were found in all samples with a similar distribution, but different content when yogurts with low and high fats were compared.

Hydroisomerization of n-Hexane Using Acidified Metal-Organic Framework and Platinum Nanoparticles.

PubMed

Sabyrov, Kairat; Jiang, Juncong; Yaghi, Omar M; Somorjai, Gabor A

2017-09-13

Exceptionally high surface area and ordered nanopores of a metal-organic framework (MOF) are exploited to encapsulate and homogeneously disperse a considerable amount of phosphotungstic acid (PTA). When combined with platinum nanoparticles positioned on the external surface of the MOF, the construct shows a high catalytic activity for hydroisomerization of n-hexane, a reaction requiring hydrogenation/dehydrogenation and moderate to strong Brønsted acid sites. Characterization of the catalytic activity and acidic sites as a function of PTA loading demonstrates that both the concentration and strength of acidic sites are highest for the catalyst with the largest amount of PTA. The MOF construct containing 60% PTA by weight produces isoalkanes with 100% selectivity and 9-fold increased mass activity as compared to a more traditional aluminosilicate catalyst, further demonstrating the capacity of the MOF to contain a high concentration of active sites necessary for the isomerization reaction.

Vegetation and Cold Trapping Modulating Elevation-dependent Distribution of Trace Metals in Soils of a High Mountain in Eastern Tibetan Plateau

PubMed Central

Bing, Haijian; Wu, Yanhong; Zhou, Jun; Li, Rui; Luo, Ji; Yu, Dong

2016-01-01

Trace metals adsorbed onto fine particles can be transported long distances and ultimately deposited in Polar Regions via the cold condensation effect. This study indicated the possible sources of silver (Ag), cadmium (Cd), copper (Cu), lead (Pb), antimony (Sb) and zinc (Zn) in soils on the eastern slope of Mt. Gongga, eastern Tibetan Plateau, and deciphered the effects of vegetation and mountain cold condensation on their distributions with elevation. The metal concentrations in the soils were comparable to other mountains worldwide except the remarkably high concentrations of Cd. Trace metals with high enrichment in the soils were influenced from anthropogenic contributions. Spatially, the concentrations of Cu and Zn in the surface horizons decreased from 2000 to 3700 m a.s.l., and then increased with elevation, whereas other metals were notably enriched in the mid-elevation area (approximately 3000 m a.s.l.). After normalization for soil organic carbon, high concentrations of Cd, Pb, Sb and Zn were observed above the timberline. Our results indicated the importance of vegetation in trace metal accumulation in an alpine ecosystem and highlighted the mountain cold trapping effect on trace metal deposition sourced from long-range atmospheric transport. PMID:27052807

Fluoride, Nitrate, and Dissolved-Solids Concentrations in Ground Waters of Washington

USGS Publications Warehouse

Lum, W. E.; Turney, Gary L.

1984-01-01

This study provides basic data on ground-water quality throughout the State. It is intended for uses in planning and management by agencies and individuals who have responsibility for or interest in, public health and welfare. It also provides a basis for directing future studies of ground-water quality toward areas where ground-water quality problems may already exist. The information presented is a compilation of existing data from numerous sources including: the Washington Departments of Ecology and Social and Health Services, the Environmental Protection Agency, as well as many other local, county, state and federal agencies and private corporations. Only data on fluoride, nitrate, and dissolved-solids concentrations in ground water are presented, as these constituents are among those commonly used to determine the suitability of water for drinking or other purposes. They also reflect both natural and man-imposed effects on water quality and are the most readily available water-quality data for the State of Washington. The percentage of wells with fluoride, nitrate, or dissolved-solids concentrations exceeding U.S. Environmental Protection Agency Primary and Secondary Drinking Water Regulations were about 1, about 3, and about 3, respectively. Most high concentrations occurred in widely separated wells. Two exceptions were: high concentrations of nitrate and dissolved solids in wells on the Hanford Department of Energy Facility and high concentrations of nitrate in the lower Yakima River basin. (USGS)

Anaerobic biodegradability and methanogenic toxicity of key constituents in copper chemical mechanical planarization effluents of the semiconductor industry.

PubMed

Hollingsworth, Jeremy; Sierra-Alvarez, Reyes; Zhou, Michael; Ogden, Kimberly L; Field, Jim A

2005-06-01

Copper chemical mechanical planarization (CMP) effluents can account for 30-40% of the water discharge in semiconductor manufacturing. CMP effluents contain high concentrations of soluble copper and a complex mixture of organic constituents. The aim of this study is to perform a preliminary assessment of the treatability of CMP effluents in anaerobic sulfidogenic bioreactors inoculated with anaerobic granular sludge by testing individual compounds expected in the CMP effluents. Of all the compounds tested (copper (II), benzotriazoles, polyethylene glycol (M(n) 300), polyethylene glycol (M(n) 860) monooleate, perfluoro-1-octane sulfonate, citric acid, oxalic acid and isopropanol) only copper was found to be inhibitory to methanogenic activity at the concentrations tested. Most of the organic compounds tested were biodegradable with the exception of perfluoro-1-octane sulfonate and benzotriazoles under sulfate reducing conditions and with the exception of the same compounds as well as Triton X-100 under methanogenic conditions. The susceptibility of key components in CMP effluents to anaerobic biodegradation combined with their low microbial inhibition suggest that CMP effluents should be amenable to biological treatment in sulfate reducing bioreactors.

Occurrence of polybrominated diphenyl ethers in floor and elevated surface house dust from Shanghai, China.

PubMed

Niu, Dong; Qiu, Yanling; Li, Li; Zhou, Yihui; Du, Xinyu; Zhu, Zhiliang; Chen, Ling; Lin, Zhifen

2018-04-24

House dust is the main source of human exposure to flame retardants by ingestion. This study investigated the occurrence of polybrominated diphenyl ethers (PBDEs) in indoor dust from 22 houses in Shanghai, China. House dust was separately collected from the floor and elevated furnishings surface (mostly between 0.5 and 2 m height) for comparison. The concentrations of ∑ 22 PBDEs ranged from 19.4 to 3280 ng/g (with a geometric mean of 203 ng/g) and from 55.1 to 792 ng/g (with a geometric mean of 166 ng/g) in floor dust (FD) and elevated surface dust (ESD), respectively. BDE-209 was the predominant congener, accounting for about 73.1% of total PBDE burdens. In terms of congener profiles, the comparison of FD and ESD revealed no significant differences except for the ratio of BDE-47/BDE-99. ESD samples displayed a ratio of BDE-47/BDE-99 very similar to commercial penta-BDE products DE-71 while the ratio in FD was exceptionally higher. Significant correlation was found between concentrations of commercial penta-BDE compositions in FD and ESD (p < 0.05). Except for some occasional values, PBDE levels in house dust exhibited temporal stability. Human exposure to PBDEs via dust ingestion was estimated. The highest daily intake of PBDEs was for toddlers by using 95th percentile concentrations of PBDEs via high dust ingestion in FD (23.07 ng/kg bw/day). About 20-fold difference in exposure estimates between toddlers and adults supports that toddlers are facing greater risk from indoor floor dust. Expectedly, this study highlighted the point that residents in Shanghai were exposed to low doses of PBDEs in house dust.

Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of organophosphate pesticides in filtered water by gas chromatography with flame photometric detection

USGS Publications Warehouse

Jha, Virendra K.; Wydoski, Duane S.

2002-01-01

A method for the isolation of 20 parent organophosphate pesticides and 5 pesticide degradates from filtered natural-water samples is described. Seven of these compounds are reported permanently with an estimated concentration because of performance issues. Water samples are filtered to remove suspended particulate matter, and then 1 liter of filtrate is pumped through disposable solid-phase extraction columns that contain octadecyl-bonded porous silica to extract the compounds. The C-18 columns are dried with nitrogen gas, and method compounds are eluted from the columns with ethyl acetate. The extract is analyzed by dual capillary-column gas chromatography with flame photometric detection. Single-operator method detection limits in all three water-matrix samples ranged from 0.004 to 0.012 microgram per liter. Method performance was validated by spiking all compounds into three different matrices at three different concentrations. Eight replicates were analyzed at each concentration level in each matrix. Mean recoveries of method compounds spiked in surface-water samples ranged from 39 to 149 percent and those in ground-water samples ranged from 40 to 124 percent for all pesticides except dimethoate. Mean recoveries of method compounds spiked in reagent-water samples ranged from 41 to 119 percent for all pesticides except dimethoate. Dimethoate exhibited reduced recoveries (mean of 43 percent in low- and medium-concentration level spiked samples and 20 percent in high-concentration level spiked samples) in all matrices because of incomplete collection on the C-18 column. As a result, concen-trations of dimethoate and six other compounds (based on performance issues) in samples are reported in this method with an estimated remark code.

Trends in polychlorinated biphenyl concentrations in Hudson River water five years after elimination of point sources

USGS Publications Warehouse

Schroeder, R.A.; Barnes, C.R.

1983-01-01

Industrial discharge of polychlorinated biphenyls (PCBs) to the Hudson River from 1950 to the mid-1970 's has resulted in serious degradation of the water. Contaminated river-bottom sediments continue to contribute PCBs to the river water. Concentrations in the sediment range from several hundred micrograms per gram near the outfall to less than 10 micrograms per gram in the lower estuary. PCBs are supplied by bottom sediments to the overlying water by two mechanisms--desorption and resuspension. Because desorption is a relatively constant process, concentrations of PCBs decrease as water discharge increases. At high flow, however, scouring by turbulence causes resuspension of PCB-laden sediment. Transport rates indicate that most PCBs enter the water from the most contaminated sediments, which are within 20 kilometers of the outfall. Mean daily transport from the upper river (except during high discharges) has decreased from 10 kilograms in 1976 to 5 kilograms in the late 1970 's and to 1 kilogram in 1981. This decrease probably results from the burial of highly contaminated sediments by cleaner sediments originating upstream. (USGS)

Chemical and biological assessment of sediments and water of Khalid Khor, Sharjah, United Arab Emirates.

PubMed

Samara, Fatin; Elsayed, Yehya; Soghomonian, Balik; Knuteson, Sandra L

2016-10-15

Water and sediments were collected on March 2013 and April 2014 from Khalid Khor creek area in United Arab Emirates to assess their quality parameters. The pH and alkalinity of the water samples were measured and their values were similar to those of shallow saltwater ecosystems. In addition, elemental analyses and organic compounds were done using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) and Gas Chromatography-Mass Spectroscopy (GC-MS), respectively. The concentration of heavy and trace metals in the water samples were within the acceptable limits except for lead which showed high values, while the concentrations of metals in the sediment samples were relatively high and ranged from 6517 to 13,768mg/kg. GC-MS analysis showed the presence of polyaromatic heterocyclic (PAHs) compounds in sediments near the shipping area and in amounts classified as highly carcinogenic; however, no polychlorinated biphenyls (PCB) were identified. Moreover, fecal bacterial contamination in water was detected in concentrations that range between 300 and 10,140 organisms/100mL. Copyright © 2016 Elsevier Ltd. All rights reserved.

Changes in patterns of persistent halogenated compounds through a pelagic food web in the Baltic Sea.

PubMed

Stephansen, Diana A; Svendsen, Tore C; Vorkamp, Katrin; Frier, Jens-Ole

2012-02-01

The concentrations and patterns of persistent halogenated compounds (PHCs), including polychlorinated biphenyls (PCBs), DDT, hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB) and polybrominated diphenyl ethers (PBDEs) were examined in a pelagic food web from the southern Baltic Sea consisting of sediment, zooplankton, sprat, Atlantic salmon and anadromous brown trout. Lipid-normalized concentrations generally increased from low trophic levels to high trophic levels, with the exception of HCHs. Due to high concentrations of PBDEs in some zooplankton samples, biomagnification of BDE-47 was only observed for salmon/sprat and trout/sprat. Sprat collected individually and from salmon stomach had significantly different lipid-normalized concentrations and varied in their PHC pattern as well, possibly indicating a large natural variation within the Baltic Sea. The highest lipid-normalized concentrations were found in brown trout. Salmon and brown trout were similar in their PHC pattern suggesting similar food sources. Variation in PHC patterns among trophic levels was not smaller than that among geographically distinct locations, confirming the importance of comparable trophic levels for the assessment of PHC patterns, e.g. for tracing migratory fish. Copyright © 2011 Elsevier Ltd. All rights reserved.

Toxicity and bioavailability of metals in the Missouri River adjacent to a lead refinery

USGS Publications Warehouse

Chapman, Duane C.; Allert, Ann L.; Fairchild, James F.; May, Thomas W.; Schmitt, Christopher J.; Callahan, Edward V.

2001-01-01

This study is an evaluation of the potential environmental impacts of contaminated groundwater from the ASARCO metals refining facility adjacent to the Missouri River in Omaha, Nebraska. Surface waters, sediments, and sediment pore waters were collected from the Burt-Izard drain, which transects the facility, and from the Missouri River adjacent to the facility. Groundwater was also collected from the facility. Waters and sediments were analyzed for inorganic contaminants, and the toxicity of the waters was evaluated with the Ceriodaphnia dubia 7-day test. Concentrations of several elemental contaminants were highly elevated in the groundwater, but not in river sediment pore waters. Lead concentrations were moderately elevated in whole sediment at one site, but lead concentrations in pore waters were low due to apparent sequestration by acid-volatile sulfides. The groundwater sample was highly toxic to C. dubia, causing 100% mortality. Even at the lowest groundwater concentration tested (6.25%) C. dubia survival was reduced; however, at that concentration, reproduction was not significantly different from upstream porewater reference samples. Sediment pore waters were not toxic, except reproduction in pore water collected from one downstream site was somewhat reduced. The decrease in reproduction could not be attributed to measured elemental contaminants.

The Effect of Soil Properties on Metal Bioavailability: Field Scale Validation to Support Regulatory Acceptance

DTIC Science & Technology

2014-06-01

unacceptable levels of the toxic metal(loid)s arsenic (As), cadmium (Cd), chromium (Cr), and lead (Pb). With the exception of Pb contaminated soils, human...remediation and closure. Lead (Pb), arsenic (As), chromium (Cr), and cadmium (Cd) are toxic (i.e., capable of producing an unwanted, deleterious effect...lagoon are contaminated with high concentrations of lead , chromium, and cadmium . 14 Deseret Chemical Depot: The Deseret Chemical Depot is

Minor elements in magnetic concentrates from the Syenite-Shonkinite Province, southern Asir, Kingdom of Saudi Arabia

USGS Publications Warehouse

Overstreet, W.C.; Day, G.W.; Botinelly, Theodore; VanTrump, George

1987-01-01

Magnetic concentrates from 106 localities in three plutons of syenite and one pluton of shonkinite in the southern Asir were analyzed spectrographically for 31 elements to determine if anomaly-enhancement techniques would identify mineralization not disclosed by conventional geochemical sample media. Positive anomalies are lacking for all elements except vanadium. Vanadium contents as high as 0.7 percent were identified in magnetic concentrates from the syenite pluton to the southeast of Suq al Ithnayn, but magnetite is sparse. This observation indicates a need to reexamine magnetite-rich drill core for possible ore-grade tenors in vanadium from the zoned pluton at Lakathah. Experimental analyses for platinum-group metals in magnetic concentrates from layered mafic plutons at Jabal Sha'i', Jabal al Ashshar, and Hishshat al Hawi should be performed to determine whether micron-size particles of the platinum-group metals are present in mafic rocks of the Arabian Shield.

Boron removal in radioactive liquid waste by forward osmosis membrane

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

Doo Seong Hwang; Hei Min Choi; Kune Woo Lee

2013-07-01

This study investigated the treatment of boric acid contained in liquid radioactive waste using a forward osmosis membrane. The boron permeation through the membrane depends on the type of membrane, membrane orientation, pH of the feed solution, salt and boron concentration in the feed solution, and osmotic pressure of the draw solution. The boron flux begins to decline from pH 7 and increases with an increase of the osmotic driving force. The boron flux decreases slightly with the salt concentration, but is not heavily influenced by a low salt concentration. The boron flux increases linearly with the concentration of boron.more » No element except for boron was permeated through the FO membrane in the multi-component system. The maximum boron flux is obtained in an active layer facing a draw solution orientation of the CTA-ES membrane under conditions of less than pH 7 and high osmotic pressure. (authors)« less

Plant growth-promoting activities of Streptomyces spp. in sorghum and rice.

PubMed

Gopalakrishnan, Subramaniam; Srinivas, Vadlamudi; Sree Vidya, Meesala; Rathore, Abhishek

2013-01-01

Five strains of Streptomyces (CAI-24, CAI-121, CAI-127, KAI-32 and KAI-90) were earlier reported by us as biological control agents against Fusarium wilt of chickpea caused by Fusarium oxysporum f. sp. ciceri (FOC). In the present study, the Streptomyces were characterized for enzymatic activities, physiological traits and further evaluated in greenhouse and field for their plant growth promotion (PGP) of sorghum and rice. All the Streptomyces produced lipase, β-1-3-glucanase and chitinase (except CAI-121 and CAI-127), grew in NaCl concentrations of up to 6%, at pH values between 5 and 13 and temperatures between 20 and 40°C and were highly sensitive to Thiram, Benlate, Captan, Benomyl and Radonil at field application level. When the Streptomyces were evaluated in the greenhouse on sorghum all the isolates significantly enhanced all the agronomic traits over the control. In the field, on rice, the Streptomyces significantly enhanced stover yield (up to 25%; except CAI-24), grain yield (up to 10%), total dry matter (up to 18%; except CAI-24) and root length, volume and dry weight (up to 15%, 36% and 55%, respectively, except CAI-24) over the control. In the rhizosphere soil, the Streptomyces significantly enhanced microbial biomass carbon (except CAI-24), nitrogen, dehydrogenase (except CAI-24), total N, available P and organic carbon (up to 41%, 52%, 75%, 122%, 53% and 13%, respectively) over the control. This study demonstrates that the selected Streptomyces which were antagonistic to FOC also have PGP properties.

Assessment and Characterisation of Ireland's Green Tides (Ulva Species)

PubMed Central

Wilkes, Robert J.; Heesch, Svenja; Bermejo, Ricardo; Johnson, Mark P.; Morrison, Liam

2017-01-01

Enrichment of nutrients and metals in seawater associated with anthropogenic activities can threaten aquatic ecosystems. Consequently, nutrient and metal concentrations are parameters used to define water quality. The European Union’s Water Framework Directive (WFD) goes further than a contaminant-based approach and utilises indices to assess the Ecological Status (ES) of transitional water bodies (e.g. estuaries and lagoons). One assessment is based upon the abundance of opportunistic Ulva species, as an indication of eutrophication. The objective of this study was to characterise Ireland’s Ulva blooms through the use of WFD assessment, metal concentrations and taxonomic identity. Furthermore, the study assessed whether the ecological assessment is related to the metal composition in the Ulva. WFD algal bloom assessment revealed that the largest surveyed blooms had an estimated biomass of 2164 metric tonnes (w/w). DNA sequences identified biomass from all locations as Ulva rigida, with the exception of New Quay, which was Ulva rotundata. Some blooms contained significant amounts of As, Cu, Cr, Pb and Sn. The results showed that all metal concentrations had a negative relationship (except Se) with the Ecological Quality Ratio (EQR). However, only in the case of Mn were these differences significant (p = 0.038). Overall, the metal composition and concentrations found in Ulva were site dependent, and not clearly related to the ES. Nevertheless, sites with a moderate or poor ES had a higher variability in the metals levels than in estuaries with a high ES. PMID:28045947

Marine phosphorites as potential resources for heavy rare earth elements and yttrium

USGS Publications Warehouse

Hein, James; Koschinsky, Andrea; Mikesell, Mariah; Mizell, Kira; Glenn, Craig R.; Wood, Ray

2016-01-01

Marine phosphorites are known to concentrate rare earth elements and yttrium (REY) during early diagenetic formation. Much of the REY data available are decades old and incomplete, and there has not been a systematic study of REY distributions in marine phosphorite deposits that formed over a range of oceanic environments. Consequently, we initiated this study to determine if marine phosphorite deposits found in the global ocean host REY concentrations of high enough grade to be of economic interest. This paper addresses continental-margin (CM) and open-ocean seamount phosphorites. All 75 samples analyzed are composed predominantly of carbonate fluorapatite and minor detrital and authigenic minerals. CM phosphorites have low total REY contents (mean 161 ppm) and high heavy REY (HREY) complements (mean 49%), while seamount phosphorites have 4–6 times higher individual REY contents (except for Ce, which is subequal; mean ΣREY 727 ppm), and very high HREY complements (mean 60%). The predominant causes of higher concentrations and larger HREY complements in seamount phosphorites compared to CM phosphorites are age, changes in seawater REY concentrations over time, water depth of formation, changes in pH and complexing ligands, and differences in organic carbon content in the depositional environments. Potential ore deposits with high HREY complements, like the marine phosphorites analyzed here, could help supply the HREY needed for high-tech and green-tech applications without creating an oversupply of the LREY.

Spatial distribution of the largest rainfall-runoff floods from basins between 2.6 and 26,000 km2 in the United States and Puerto Rico

NASA Astrophysics Data System (ADS)

O'Connor, Jim E.; Costa, John E.

2004-01-01

We assess the spatial distribution of the largest rainfall-generated streamflows from a database of 35,663 flow records composed of the largest 10% of annual peak flows from each of 14,815 U.S. Geological Survey stream gaging stations in the United States and Puerto Rico. High unit discharges (peak discharge per unit contributing area) from basins with areas of 2.6 to 26,000 km2 (1-10,000 mi2) are widespread, but streams in Hawaii, Puerto Rico, and Texas together account for more than 50% of the highest unit discharges. The Appalachians and western flanks of Pacific coastal mountain systems are also regions of high unit discharges, as are several areas in the southern Midwest. By contrast, few exceptional discharges have been recorded in the interior West, northern Midwest, and Atlantic Coastal Plain. Most areas of high unit discharges result from the combination of (1) regional atmospheric conditions that produce large precipitation volumes and (2) steep topography, which enhances precipitation by convective and orographic processes and allows flow to be quickly concentrated into stream channels. Within the conterminous United States, the greatest concentration of exceptional unit discharges is at the Balcones Escarpment of central Texas, where maximum U.S. rainfall amounts apparently coincide with appropriate basin physiography to produce many of the largest measured U.S. floods. Flood-related fatalities broadly correspond to the spatial distribution of high unit discharges, with Texas having nearly twice the average annual flood-related fatalities of any other state.

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 start of a fish die-off in 2003. Documented evidence indicates that LDOEs played a role in three fish die-offs in the mid-1990s as well. In the historical context of 15 years of climate and water-quality data, 3 out of 4 of the recent fish die-off years, 1996, 1997, and 2003, were characterized by low winds and high temperatures in July or August coincident with the start of the die-off. High temperatures accelerate the oxygen demanding processes that lead to a LDOE. The role of low winds remains inconclusive, but it could include the development of stratification in the water column and/or the alteration of the wind-driven circulation pattern. At a site centrally located in the study area, die-off years could be successfully identified in the historical data by screening for water characterized by exceptionally low chlorophyll a concentration, exceptionally low dissolved oxygen concentration throughout the water column (not just near the bottom), and exceptionally high ammonia concentration and water temperature, just prior to or coincident with the start of a fish die-off. These conditions indicate that a severe decline in the AFA bloom and conversion of most of the organic matter into inorganic form had taken place.

Survey of polyfluorinated chemicals (PFCs) in the atmosphere over the northeast Atlantic Ocean

NASA Astrophysics Data System (ADS)

Shoeib, Mahiba; Vlahos, Penny; Harner, Tom; Peters, Andrew; Graustein, Margaret; Narayan, Julie

2010-08-01

High volume air sampling in Bermuda, Sable Island (Nova Scotia) and along a cruise track from the Gulf of Mexico to northeast coast of the USA, was carried out to assess air concentrations, particle-gas partitioning and transport of polyfluorinated chemicals (PFCs) in this region. Samples were collected in the summer of 2007. Targeted compounds included the neutral PFCs: fluorotelomer alcohols (FTOHs), perfluoroalkyl sulfonamides (FOSAs) and perfluoroalkyl sulfonamido ethanols (FOSEs). Among the FTOHs, 8:2 FTOH was dominant in all samples. Sum of the concentration of FTOHs (gas+particle phase) were higher in Bermuda (mean, 34 pg m -3) compared to Sable Island (mean, 16 pg m -3). In cruise samples, sum of FTOHs were highly variable (mean, 81 pg m -3) reflecting contributions from land-based sources in the northeast USA with concentrations reaching as high as 156 pg m -3. Among the FOSAs and FOSEs, MeFOSE was dominant in all samples. In Bermuda, levels of MeFOSE were exceptionally high (mean, 62 pg m -3), exceeding the FTOHs. Sable Island samples also exhibited the dominance of MeFOSE but at a lower concentration (mean, 15 pg m -3). MeFOSE air concentrations (pg m -3) in cruise samples ranged from 1.6 to 73 and were not linked to land-based sources. In fact high concentrations of MeFOSE observed in Bermuda were associated with air masses that originated over the Atlantic Ocean. The partitioning to particles for 8:2 FTOH, 10:2 FTOH, MeFOSE and EtFOSE ranged from as high as 15 to 42% for cruise samples to 0.9 to 14% in Bermuda. This study provides key information for validating and developing partitioning and transport models for the PFCs.

Characteristics and potential sources of polychlorinated biphenyl pollution in a suburban area of Guangzhou, southern China

NASA Astrophysics Data System (ADS)

Li, Qilu; Wang, Yan; Luo, Chunling; Li, Jun; Zhang, Gan

2017-05-01

In this study, 52 paired gas and particle samples were collected from a suburban field in Guangzhou in 2012 using a high-volume active air sampler; they were then analysed for 30 polychlorinated biphenyl (PCB) congeners via gas chromatography with tandem mass spectrometry. Total PCB concentrations ranged from 97.4 to 853 pg m-3. This was a moderate level compared with other cities, undeveloped areas, and electronic waste disposal sites. Atmospheric concentrations of PCBs did not exhibit notable diurnal or seasonal variations, except for a few high measurement. Tetra- and tri-CBs were the predominant PCB compounds, with an average combined contribution of 81.9%. CB-77 was the dominant congener in the particle phase due to a few samples with extremely high mass fraction of CB-77 and relatively low concentrations of other PCBs. Based on measurements of pollution characteristics including diurnal and seasonal variations, we used correlation analysis, principal component analysis and back trajectory modeling to deduce that electronic manufacturing and recycling activities, pigment/paint production, and waste incineration plants are possible sources of PCBs in Guangzhou. Of these sources, the high observed contributions of CB-77 originated mainly from the pigment/paint industry.

Occurrence of and trends in selected sediment-associated contaminants in Caddo Lake, East Texas, 1940-2002

USGS Publications Warehouse

Wilson, Jennifer T.

2003-01-01

Bottom-sediment cores were collected from four sites in Caddo Lake in East Texas during May 2002 for analyses of radionuclides (for age dating), organochlorine pesticides, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and major and trace elements, and to describe the occurrence and trends of these sediment-associated contaminants. The Goose Prairie Creek and Harrison Bayou sites receive drainage from an area that includes parts of the now-closed Longhorn Army Ammunitions Plant. The mid-lake site is relatively close to dense oil and gas operations in the lake. The Carter Lake site receives minimal discharge from developed areas. Sediment age (deposition) dates represented in the cores ranged from 1940 to 2002. The only organochlorine compounds detected in all core samples were the DDT degradation products DDE or DDD, and PCB Aroclors 1242, 1254, and 1260 were detected only at the Goose Prairie Creek site. One or more of the DDE concentrations at all sites exceeded a consensus-based threshold effect concentration (on benthic biota), but none exceeded a consensus-based probable effect concentration. The Goose Prairie Creek site had significant downward trends in concentrations of organochlorine compounds, except for no trend in DDE concentrations. The Ammunitions Plant is a possible historical source of the few organochlorine compounds detected at the Goose Prairie Creek and Harrison Bayou sites. PAH concentrations at all sites were below respective threshold effect concentrations. Highest PAH concentrations at all four sites were of C2- alkylated naphthalenes. Nearly all statistically significant PAH trends in the cores were downward. On the basis of PAH source-indicator ratios, the majority of PAH compounds appear to have originated from uncombusted sources such as leaks or spills from oil and gas operations or vehicles (automobiles, boats, aircraft) in the Caddo Lake area. Concentrations of several of the eight trace elements with threshold effect concentrations and probable effect concentrations (among 26 analyzed) were above the respective threshold effect concentrations, but all, except one lead concentration at the Goose Prairie Creek site (deposited about 1961), were below respective probable effect concentrations. Among trace element concentrations at the four sites, lead and mercury were consistently relatively high at the Goose Prairie Creek site. Again the Ammunitions Plant, because of its proximity and history of industrial activities, is the suspected primary source. Statistically significant trends in trace element concentrations were mixed, but more were downward than upward. Computations to indicate the dominant source (atmospheric fallout or drainage area) of mercury to the Caddo Lake sediment core sites (except Carter Lake) indicate that about one-third of the mercury at the Goose Prairie Creek site might result from drainage area sources. No drainage area sources were indicated for the Harrison Bayou and mid-lake sites. Arsenic, cadmium, and zinc concentrations were highest at the Carter Lake site. No relation between the relatively higher trace element concentrations and any potential source of contamination in the Carter Lake drainage area (for example, oil and gas operations, a road, a boat ramp) is indicated.

Acrylamide in Japanese processed foods and factors affecting acrylamide level in potato chips and tea.

PubMed

Yoshida, Mitsuru; Ono, Hiroshi; Chuda, Yoshihiro; Yada, Hiroshi; Ohnishi-Kameyama, Mayumi; Kobayashi, Hidetaka; Ohara-Takada, Akiko; Matsuura-Endo, Chie; Mori, Motoyuki; Hayashi, Nobuyuki; Yamaguchi, Yuichi

2005-01-01

Acrylamide concentrations in processed foods sold in Japanese markets were analyzed by LC-MS/MS and GC-MS methods. Most potato chips and whole potato-based fried snacks showed acrylamide concentration higher than 1000 microg/kg. The concentrations in non-whole potato based Japanese snacks, including rice crackers and candied sweet potatoes, were less tha. 350 microg/kg. Those in instant precooked noodles were less than 100 microg/kg with only one exception. The effect of storage condition of potato tubers on acrylamide concentration in potato chips after frying was also investigated. Sugar content in the tubers increased during cold storage, and the acrylamide concentration increased accordingly. The concentrations of asparagine and other amino acids, however, did not change during the cold storage. High correlations were observed between the acrylamide content in the chips and glucose and fructose contents in the tubers. This fact indicated that the limiting factor for acrylamide formation in potato chips is reducing sugar, not asparagine content in the tubers. Effects of roasting time and temperature on acrylamide concentration in roasted green tea are also described.

Evaluation on determination of iodine in coal by energy dispersive X-ray fluorescence

USGS Publications Warehouse

Wang, B.; Jackson, J.C.; Palmer, C.; Zheng, B.; Finkelman, R.B.

2005-01-01

A quick and inexpensive method of relative high iodine determination from coal samples was evaluated. Energy dispersive X-ray fluorescence (EDXRF) provided a detection limit of about 14 ppm (3 times of standard deviations of the blank sample), without any complex sample preparation. An analytical relative standard deviation of 16% was readily attainable for coal samples. Under optimum conditions, coal samples with iodine concentrations higher than 5 ppm can be determined using this EDXRF method. For the time being, due to the general iodine concentrations of coal samples lower than 5 ppm, except for some high iodine content coal, this method can not effectively been used for iodine determination. More work needed to meet the requirement of determination of iodine from coal samples for this method. Copyright ?? 2005 by The Geochemical Society of Japan.

Contribution of GIS to evaluate surface water pollution by heavy metals: Case of Ichkeul Lake (Northern Tunisia)

NASA Astrophysics Data System (ADS)

Yazidi, Amira; Saidi, Salwa; Ben Mbarek, Nabiha; Darragi, Fadila

2017-10-01

The concentrations of nutrients and heavy elements in the surface water of the lake Ichkeul, main wadis which feed directly and thermal springs that flow into the lake, are measured to evaluate these chemical elements. There are used to highlight the interactions between these different aquatic compartments of Ichkeul. All metal concentrations in lake water, except Cu, were lower than the maximum permitted concentration for the protection of aquatic life. The results show that the highest concentrations are located in the eastern and south-eastern part of the lake where the polluted water comes from the lagoon of Bizerte through the wadi Tinja as well as from the city of Mateur through the wadi Joumine. The pollution indices and especially the heavy metal evaluation index (HEI) show high pollution specially located at the mouths of wadis and an increase of heavy metal concentrations, as a result of uncontrolled releases of domestic and industrial wastewater.

Characteristics of carbonaceous aerosols at a pair of suburban and downtown sites in Nanjing, China

NASA Astrophysics Data System (ADS)

Cui, H.; Zhang, J.; Zhao, Y.

2014-12-01

Carbonaceous species in PM2.5 were measured in three seasons (except winter) in downtown and around a year in suburban in Nanjing. In particular, the OC and EC concentrations were continuously measured with 1-h interval at both sites. The mean concentrations of PM2.5, OC, EC were 85.9 μg/m3, 10.4 μg/m3, 4.2 μg/m3 and 63.4 μg/m3, 8.1 μg/m3, 5.3μg/m3 for downtown and suburban respectively. At the suburban site, compared to the lowest average concentration in spring, the relatively higher concentration of carbonaceous aerosol in summer was caused by biomass-burning activities. Significant increasing peaks of OC (up to 122.9 ug/m3) and EC (up to 35.8 ug/m3) in suburban were recorded in the June 10th night, and it is indicated using back trajectory that the air mass came through nearby agriculture areas. On the other hand, the OC and EC concentrations during the 2nd AYG (Asian Youth Games, Aug 16th - 24th in 2013) compared to that in rest days in August reduced by 21% and 10%, respectively, attributing to the effective control measures on reduction of industrial point sources, temporary control of motor vehicle and fugitive dusts. Rations of OC/EC in suburban were much lower than that in downtown. This might be due to the fact that the sampling point in suburban is quite close (in 400 meters) to a main highway. Both OC and EC concentrations in suburban were higher in nighttime than daytime, except OC in summer, indicating the existence of strong SOC and supported by high OC/EC and O3 at noon. The annual average SOC estimated by EC-tracer methods occupied 34.5% and 36.7% of the total OC for the downtown and suburban areas, respectively. OC/EC correlations in suburban were much weaker than those from downtown areas, which shows suburban areas is much more affected by long-range transport of pollution and/or complex sources including domestic coal combustion, biomass burning, industrial and transportation, especially in three other seasons except winter, which is also supported by poor correlations between carbonaceous species and gaseous pollutants (NO2, SO2, CO) in spring at suburban site.

Maternal exposure to metals—Concentrations and predictors of exposure

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

Callan, A.C., E-mail: a.callan@ecu.edu.au; Hinwood, A.L.; Ramalingam, M.

2013-10-15

A variety of metals are important for biological function but have also been shown to impact health at elevated concentrations, whereas others have no known biological function. Pregnant women are a vulnerable population and measures to reduce exposure in this group are important. We undertook a study of maternal exposure to the metals, aluminium, arsenic, copper, cobalt, chromium, lithium, manganese, nickel, selenium, tin, uranium and zinc in 173 participants across Western Australia. Each participant provided a whole blood and urine sample, as well as drinking water, residential soil and dust samples and completed a questionnaire. In general the concentrations ofmore » metals in all samples were low with the notable exception of uranium (blood U mean 0.07 µg/L, range <0.01–0.25 µg/L; urinary U mean 0.018 µg/g creatinine, range <0.01–0.199 µg/g creatinine). Factors that influenced biological concentrations were consumption of fish which increased urinary arsenic concentrations, hobbies (including mechanics and welding) which increased blood manganese concentrations and iron/folic acid supplement use which was associated with decreased concentrations of aluminium and nickel in urine and manganese in blood. Environmental concentrations of aluminium, copper and lithium were found to influence biological concentrations, but this was not the case for other environmental metals concentrations. Further work is underway to explore the influence of diet on biological metals concentrations in more detail. The high concentrations of uranium require further investigation. -- Highlights: • High concentrations of uranium with respect to international literature. • Environmental concentrations of Al, Cu and Li influenced urinary concentrations. • Exposure to mechanics/welding hobbies increased blood Mn concentrations. • Iron/Folic acid supplements reduced biological concentrations of Al, Ni and Mn.« less

Investigation of saponification for determination of polychlorinated biphenyls in marine sediments.

PubMed

Numata, Masahiko; Yarita, Takashi; Aoyagi, Yoshie; Yamazaki, Misako; Takatsu, Akiko

2005-02-01

The effects of saponification conditions (temperature and water content of saponifying solution) on the determination of chlorinated biphenyls (CBs) in marine sediments were investigated. Although highly chlorinated biphenyls (nona- to deca-CBs) decomposed during high-temperature saponification, the degree of degradation was reduced by adding water to the ethanolic potassium hydroxide saponifying solution. Room-temperature saponification yielded quantitative recovery of highly chlorinated biphenyl surrogates but low extraction efficiencies of lightly chlorinated biphenyls (mono- to di-CBs). The same samples were analyzed by other extraction techniques, for example, pressurized liquid extraction, and analytical results were compared. The mono- and di-CB concentrations were correlated with the extraction temperatures of various extraction techniques. In particular, the concentrations of some CB congeners (CB11, CB14) were higher with saponification. The low degree of degradation of highly chlorinated biphenyls and the high recovery of lightly chlorinated biphenyls were compatible when room-temperature and high-temperature saponification were combined. Except for the anomalies of CB11 and CB14, the combined method gave satisfactory results for analysis of PCBs.

Total particle, sulfate, and acidic aerosol emissions from kerosene space heaters

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

Leaderer, B.P.; Boone, P.M.; Hammond, S.K.

1990-06-01

Chamber studies were conducted on four unvented kerosene space heaters to assess emissions of total particle, sulfate, and acidic aerosol. The heaters tested represented four burner designs currently in use by the public. Kerosene space heaters are a potential source of fine particles ({<=} 2.5-{mu}m diameter), sulfate, and acidic aerosol indoors. Fine particle concentrations in homes in which the heaters are used may be increased in excess of 20 {mu}g/m{sup 3} over background levels. Sulfate and acidic aerosol levels in such homes could exceed average and peak outdoor concentrations. Maltuned heaters could produce exceptionally high levels of all air contaminantsmore » measured.« less

Total particle, sulfate, and acidic aerosol emissions from kerosene space heaters

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

Leaderer, B.P.; Boone, P.M.; Hammond, S.K.

1990-01-01

The article discusses chamber studies of four unvented kerosene space heaters to assess emissions of total particle, sulfate, and acidic aerosol. The heaters tested represented four burner designs currently in use by the public. Kerosene space heaters are a potential source of fine particles (= or < 2.5 micrometer diameter), sulfate, and acidic aerosol indoors. Fine particle concentrations in houses in which the heaters are used may be increased in excess of 20 micrograms/m3 over background levels. Sulfate and acidic aerosol levels in such houses could exceed average and peak outdoor concentrations. Maltuned heaters could produce exceptionally high levels ofmore » all air contaminants measured.« less

Degradation of pesticides in biobeds: the effect of concentration and pesticide mixtures.

PubMed

Fogg, Paul; Boxall, Alistair B A; Walker, Allan

2003-08-27

Biobeds aim to create an environment whereby any pesticide spills are retained and then degraded, thus reducing the potential for surface or groundwater contamination. Biobeds may receive high concentrations of relatively complex mixtures of pesticides. The effects of concentration and pesticide interaction on degradation rate were therefore investigated. At concentrations up to 20 times the maximum recommended application rate for isoproturon and chlorothalonil, the rate of degradation in topsoil and biomix decreased with increasing concentration. With the exception of isoproturon at concentrations above 11 mg kg(-1), degradation was quicker in biomix (a composted mixture of topsoil, compost, and wheat straw) than in topsoil. One possible explanation for faster isoproturon degradation in topsoil as compared to biomix may be that previous treatments of isoproturon applied to the field soil as part of normal agricultural practices had resulted in proliferation of microbial communities specifically adapted to use isoproturon as an energy source. Such microbial adaptation could enhance the performance of a biobed. Studies with a mixture of isoproturon and chlorothalonil showed that interactions between pesticides are possible. In biomix, the degradation of either isoproturon or chlorothalonil was unaffected by the presence of the other pesticide, whereas in topsoil, isoproturon DT(50) values increased from 18.5 to 71.5 days in the presence of chlorothalonil. These studies suggest that biobeds appear capable of treating high concentrations of more than one pesticide.

Distribution and bioavailability of Cr in central Euboea, Greece

NASA Astrophysics Data System (ADS)

Megremi, Ifigeneia

2010-06-01

Plants and soils from central Euboea, were analyzed for Cr(totai), Cr(VI), Ni, Mn, Fe and Zn. The range of metal concentrations in soils is typical to those developed on Fe-Ni laterites and ultramafic rocks. Their bioavailability was expressed in terms of concentrations extractable with EDTA and 1 M HNO3, with EDTA having a limited effect on metal recovery. Cr(VI) concentrations in soils evaluated by alkaline digestion solution were lower than phytotoxic levels. Chromium and Ni — and occasionally Zn — in the majority of plants were near or above toxicity levels. Cr(VI) concentrations in plants were extremely low compared to total chromium concentrations. Cr(total) in ground waters ranged from <1 μg.L-1 to 130 μg.L-1, with almost all chromium present as Cr(VI). With the exception of Cr(total) and in some cases Zn, all elements were below regulatory limits for drinking water. On the basis of Ca, Mg, Cr(total) and Si ground waters were classified into three groups: Group(I) with Cr concentrations less than 1 μg.L-1 from a karstic aquifer; Group(II) with average concentrations of 24 μg.L-1 of Cr and relatively high Si associated with ophiolites; and Group(III) with Cr concentrations of up to 130 μg.L-1, likely due to anthropogenic activity. Group(III) is comparable to ground waters from Assopos basin, characterized by high Cr(VI) concentrations, probably due to industrial actrivities.

Chaophilic or chaotolerant fungi: a new category of extremophiles?

PubMed Central

Zajc, Janja; Džeroski, Sašo; Kocev, Dragi; Oren, Aharon; Sonjak, Silva; Tkavc, Rok; Gunde-Cimerman, Nina

2014-01-01

It is well known that few halophilic bacteria and archaea as well as certain fungi can grow at the highest concentrations of NaCl. However, data about possible life at extremely high concentrations of various others kosmotropic (stabilizing; like NaCl, KCl, and MgSO4) and chaotropic (destabilizing) salts (NaBr, MgCl2, and CaCl2) are scarce for prokaryotes and almost absent for the eukaryotic domain including fungi. Fungi from diverse (extreme) environments were tested for their ability to grow at the highest concentrations of kosmotropic and chaotropic salts ever recorded to support life. The majority of fungi showed preference for relatively high concentrations of kosmotropes. However, our study revealed the outstanding tolerance of several fungi to high concentrations of MgCl2 (up to 2.1 M) or CaCl2 (up to 2.0 M) without compensating kosmotropic salts. Few species, for instance Hortaea werneckii, Eurotium amstelodami, Eurotium chevalieri and Wallemia ichthyophaga, are able to thrive in media with the highest salinities of all salts (except for CaCl2 in the case of W. ichthyophaga). The upper concentration of MgCl2 to support fungal life in the absence of kosmotropes (2.1 M) is much higher than previously determined to be the upper limit for microbial growth (1.26 M). No fungal representatives showed exclusive preference for only chaotropic salts (being obligate chaophiles). Nevertheless, our study expands the knowledge of possible active life by a diverse set of fungi in biologically detrimental chaotropic environments. PMID:25566222

Estrogen receptor quantitation and staging as complementary prognostic indicators in breast cancer: a study of 583 patients.

PubMed

Godolphin, W; Elwood, J M; Spinelli, J J

1981-12-01

Estrogen receptor (ER) quantity was measured at the time of primary diagnosis on 583 patients with breast cancer seen at the major treatment centre in British Columbia between 1975 and 1979. Survival rates (overall, recurrence-free and post-recurrence) were assessed relative to ER concentration, staging, menopausal status, age, differentiation, and therapy. A linear trend in increased survival was demonstrable through variations in ER concentration from less than 1 to greater than 260 fmoles/mg cytosol protein. This trend was highly significant and remained after adjustment for stage, menopausal status, and age, and was seen for all groups of patients except those with metastatic disease. The association of high ER concentration with increased recurrence-free survival was not due to differing responses to adjuvant therapy, but the trend in post-recurrence survival was only significant in patients who had received hormonal therapy. Survival was as strongly associated with receptor concentration as with staging, and these two factors were almost completely independent. A proportional hazards model was fitted to produce predictions of survival, and showed that TNM stage III patients with high ER concentrations have a better survival than stage I or II patients with lower ER concentrations. This suggests that quantitative assessment of ER status is essential to definition of risk in breast cancer patients and that stratification in clinical trials and consideration for adjuvant therapy ought to be guided, in part, by a standardized ER-quantitative determination performed on the primary tumor.

Allelopathic Effects, Physiological Responses and Phenolic Compounds in Litter Extracts of Juniperus rigidaSieb. et Zucc.

PubMed

Liu, Jing; Li, Dengwu; Wang, Dongmei; Liu, Yu; Song, Huiying

2017-08-01

The allelopathic effects of Juniperus rigida litter aqueous extract (LE) on wheat and Pinus tabuliformis were studied, as well as the physiological responses to the extract. High concentration LE (0.10 g Dw/ml) significantly inhibited the seed germination and seedling growth in receptor plants. The chlorophyll content and root activity in the wheat seedlings were reduced significantly across all treatments; however, those were more prominently reduced at high concentration (0.10 g Dw/ml) but received little stimulation at low concentration (0.025 g Dw/ml) in P. tabuliformis. The content of malonaldehyde (MDA) increased with increasing concentrations of LE, except at 0.025 g Dw/ml. Activities of antioxidant enzymes (POD, CAT and SOD) in receptor plants were all significantly inhibited at high concentrations but stimulated at low concentrations. These results demonstrate that the aqueous extract from J. rigida litter has allelopathic potential. Various phenolic compounds were identified in litter aqueous extract and litter ethanol extract by HPLC. The phenolic compound content in the aqueous extract was significantly lower than that in the ethanol extract. Chlorogenic acid and podophyllotoxin were the predominant phenolic compounds in both types of litter extracts. These findings suggest that the seed germination and seedling growth of P. tabuliformis and wheat would be inhibited when planted near large amounts J. rigida litter. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

Concentrations and loads of suspended sediment and trace element pollutants in a small semi-arid urban tributary, San Francisco Bay, California.

PubMed

McKee, Lester J; Gilbreath, Alicia N

2015-08-01

Water-quality policy documents throughout the world often identify urban stormwater as a large and controllable impact to sensitive ecosystems, yet there is often limited data to characterize concentrations and loads especially for rare and more difficult to quantify pollutants. In response, concentrations of suspended sediments and silver, mercury and selenium including speciation, and other trace elements were measured in dry and wet weather stormwater flow from a 100% urban watershed near San Francisco. Suspended sediment concentrations ranged between 1.4 and 2700 mg/L and varied with storm intensity. Turbidity was shown to correlate strongly with suspended sediments and most trace elements and was used as a surrogate with regression to estimate concentrations during unsampled periods and to compute loads. Mean suspended sediment yield was 31.5 t/km(2)/year. Total mercury ranged between 1.4 and 150 ng/L and was, on average, 92% particulate, 0.9% methylated, and 1.2% acid labile. Total mercury yield averaged 5.7 μg/m(2)/year. Total selenium ranged between non-detect and 2.9 μg/L and, on average, the total load (0.027 μg/m(2)/year) was 61% transported in dissolved phase. Selenate (Se(VI)) was the dominant species. Silver concentrations ranged between non-detect and 0.11 μg/L. Concentrations and loads of other trace elements were also highly variable and were generally similar to other urban systems with the exceptions of Ag and As (seldom reported) and Cr and Zn which exhibited concentrations and loads in the upper range of those reported elsewhere. Consistent with the semi-arid climatic setting, >95% of suspended sediment, 94% of total Hg, and 85-95 % of all other trace element loads were transported during storm flows with the exception of selenium which showed an inverse relationship between concentration and flow. Treatment of loads is made more challenging in arid climate settings due to low proportions of annual loads and greater dissolved phase during low flow conditions. This dataset fills an important local data gap for highly urban watersheds of San Francisco Bay. The field and interpretative methods, the uniqueness of the analyte list, and resulting information have general applicability for managing pollutant concentrations and loads in urban watersheds in other parts of the world and may have particularly useful application in more arid climates.

Temporal trends of bulk precipitation and stream water chemistry (1977-1997) in a small forested area, Krusne hory, northern Bohemia, Czech Republic

USGS Publications Warehouse

Peters, N.E.; Cerny, J.; Havel, M.; Krejci, R.

1999-01-01

The Krusne hory (Erzgebirge or Ore Mountains) has been heavily affected by high atmospheric pollutant deposition caused by fossil fuel combustion in an adjacent Tertiary coal basin. Long-term routine sampling of bulk precipitation (1977-1996) and stream water (1977-1998) in a forested area on the south-eastern slope of the mountains were used to evaluate trends and patterns in solute concentration and flux with respect to controlling processes. From 1977 to 1996, the annual volume-weighted Ca2+ and SO42- concentrations decreased in bulk precipitation. However, after 1989, when a pronounced and continuous decrease occurred in coal production, annual volume-weighted concentrations decreased for most solutes, except H+. The concentration decreases were marked, with 1996 levels at or below 50% of those in 1989. The lack of a trend in H+ is attributed to similar decreases in both acid anions and neutralizing base cations. Stream water concentrations of most solutes, i.e. H+, Ca2+, Mg2+, SO42- and NO3-, were highest at the onset of sampling in 1977, decreased markedly from 1977 to 1983 and decreased more gradually from 1983 to 1998. The spruce forest die-back and removal reduced dry deposition of these solutes by reducing the filtering action, which was provided by the forest canopy. A notable decrease in stream water Ca2+ concentrations occurred after 1995 and may be due to the depletion of Ca2+, which was provided by catchment liming in 1986, 1988 and 1989. Solute flux trends in bulk atmospheric deposition and stream water generally were not significant and the lack of trend is attributed to the large interannual variability in precipitation quantity and runoff, respectively. All solutes except Na+ varied seasonally. The average seasonal concentrations varied between the solutes, but for most solutes were highest in winter and spring and lowest in summer, correlating with the seasonal trend and runoff. For Ca2+, Mg2+ and SO42-, the concentration minimum occurs in September and the maximum occurs in February or March, correlating with the seasonal baseflow. These solutes are primarily controlled by the contribution of soil water and groundwater to stream flow. During snowmelt, the meltwater generally causes concentrations to decrease as soil water and groundwater are diluted. For NO3, average minimum concentrations occur in August at the end of the growing season concurrent with the lowest stream flow, and the maximum occurs in February and March with high stream flow during snowmelt. Seasonal stream water NO3- concentration variations are large compared with the long-term decrease.The Krusne hory (Erzgebirge or Ore Mountains) has been heavily affected by high atmospheric pollutant deposition caused by fossil fuel combustion in an adjacent Tertiary coal basin. Long-term routine sampling of bulk precipitation (1977-1996) and stream water (1977-1998) in a forested area on the south-eastern slope of the mountains were used to evaluate trends and patterns in solute concentration and flux with respect to controlling processes. From 1977 to 1996, the annual volume-weighted Ca2+ and SO42- concentrations decreased in bulk precipitation. However, after 1989, when a pronounced and continuous decrease occurred in coal production, annual volume-weighted concentrations decreased for most solutes, except H+. The concentration decreases were marked, with 1996 levels at or below 50% of those in 1989. The lack of a trend in H+ is attributed to similar decreases in both acid anions and neutralizing base cations. Stream water concentrations of most solutes, i.e. H+, Ca2+, Mg2+, SO42- and NO3-, were highest at the onset of sampling in 1977, decreased markedly from 1977 to 1983 and decreased more gradually from 1983 to 1998. The spruce forest die-back and removal reduced dry deposition of these solutes by reducing the filtering action, which was provided by the forest canopy. A notable decrease in stream water Ca2+ concentrations occurred after 1995 an

Fuel-air mixing and combustion in a two-dimensional Wankel engine

NASA Technical Reports Server (NTRS)

Shih, T. I.-P.; Schock, H. J.; Ramos, J. I.

1987-01-01

A two-equation turbulence model, an algebraic grid generalization method, and an approximate factorization time-linearized numerical technique are used to study the effects of mixture stratification at the intake port and gaseous fuel injection on the flow field and fuel-air mixing in a two-dimensional rotary engine model. The fuel distribution in the combustion chamber is found to be a function of the air-fuel mixture fluctuations at the intake port. It is shown that the fuel is advected by the flow field induced by the rotor and is concentrated near the leading apex during the intake stroke, while during compression, the fuel concentration is highest near the trailing apex and is lowest near the rotor. It is also found that the fuel concentration near the trailing apex and rotor is small except at high injection velocities.

Study of the effects of focused high-energy boron ion implantation in diamond

NASA Astrophysics Data System (ADS)

Ynsa, M. D.; Agulló-Rueda, F.; Gordillo, N.; Maira, A.; Moreno-Cerrada, D.; Ramos, M. A.

2017-08-01

Boron-doped diamond is a material with a great technological and industrial interest because of its exceptional chemical, physical and structural properties. At modest boron concentrations, insulating diamond becomes a p-type semiconductor and at higher concentrations a superconducting metal at low temperature. The most conventional preparation method used so far, has been the homogeneous incorporation of boron doping during the diamond synthesis carried out either with high-pressure sintering of crystals or by chemical vapour deposition (CVD) of films. With these methods, high boron concentration can be included without distorting significantly the diamond crystalline lattice. However, it is complicated to manufacture boron-doped microstructures. A promising alternative to produce such microstructures could be the implantation of focused high-energy boron ions, although boron fluences are limited by the damage produced in diamond. In this work, the effect of focused high-energy boron ion implantation in single crystals of diamond is studied under different irradiation fluences and conditions. Micro-Raman spectra of the sample were measured before and after annealing at 1000 °C as a function of irradiation fluence, for both superficial and buried boron implantation, to assess the changes in the diamond lattice by the creation of vacancies and defects and their degree of recovery after annealing.

Aquatic environmental risk assessment for human use of the old antibiotic sulfamethoxazole in Europe.

PubMed

Straub, Jürg Oliver

2016-04-01

Sulfamethoxazole (SMX) is an old sulfonamide antibiotic that was launched first in combination with trimethoprim in 1969 by F.Hoffmann-La Roche. Although sales figures for SMX have been declining over the past 20 yr, the compound is still widely used; moreover, many measured environmental concentrations (MECs) are available from Europe, the United States, Asia, Australia, and Africa. To assess aquatic risks of SMX in Europe, the exposure of European surface waters was predicted based on actual sales figures from IMS Health, incorporating environmental fate data on one side, and based on collated MECs representing more than 5500 single measurements in Europe on the other. Environmental effects were assessed using chronic and subchronic ecotoxicity data for 16 groups of aquatic organisms, from periphyton communities to cyanobacteria, algae, higher plants, various invertebrates, and vertebrates. Predicted no-effect concentrations (PNECs) were derived using both deterministic and probabilistic methodology. The predicted environmental concentration (PEC)/PNEC and MEC/PNEC comparisons overall showed no appreciable risk, except in a low incidence (<0.55%) of cases in which exceptionally high MECs led to MEC/PNEC risk characterization ratios greater than 1. The PNECs derived in the present study can be used to extend aquatic environmental risk assessment for SMX to other continents. No risk appears for indirect human exposure to SMX via the environment. © 2015 SETAC.

In situ arsenic removal in an alkaline clastic aquifer

USGS Publications Warehouse

Welch, A.H.; Stollenwerk, K.G.; Paul, A.P.; Maurer, D.K.; Halford, K.J.

2008-01-01

In situ removal of As from ground water used for water supply has been accomplished elsewhere in circum-neutral ground water containing high dissolved Fe(II) concentrations. The objective of this study was to evaluate in situ As ground-water treatment approaches in alkaline ground-water (pH > 8) that contains low dissolved Fe (

A preliminary analysis of the effects of bisphenol A on the plant root growth via changes in endogenous plant hormones.

PubMed

Li, Xingyi; Wang, Lihong; Wang, Shengman; Yang, Qing; Zhou, Qing; Huang, Xiaohua

2018-04-15

Bisphenol A (BPA) is ubiquitous in the environment worldwide, affecting plant growth and development. Endogenous plant hormones serve as switches that regulate plant growth and development. However, plants have different physiological requirements and environmental adaptive capacities during the different growth stages. Here, we investigated the effects of BPA on soybean (Glycine max L.) root growth at the three growth stages and analyzed the mechanisms underlying the effects of BPA on the root growth by assessing changes in endogenous hormone. The results showed that low concentration of BPA (1.5mgL -1 ) improved root growth (except at the seed-filling stage), increased indole-3-acetic acid (IAA) content at the first two growth stages, and increased zeatin (ZT) content and decreased gibberellic acid (GA 3 ) content at the seedling stage. But low concentration of BPA caused decreased ethylene (ETH) contents and constant abscisic acid (ABA) content at all three stages. However, BPA at moderate and high concentrations (6.0 and 12.0mgL -1 ) inhibited root growth, causing the decreased IAA, GA 3 and ETH contents and increased ABA content at all three growth stages. The change degrees of above indices were weakened with prolonging the growth stages. After BPA withdrawal, both the root growth and the hormone contents recovered (with the exception of ZT and ETH), and the recovery degrees had negative correlation with the BPA exposure concentration and had positive correlation with the growth stage. Changes in residual BPA content in the roots were also observed at different BPA concentrations and different growth stages. Our results demonstrated the effects of BPA on root growth were related to BPA-induced changes in hormone, which performed differently at various growth stages. Copyright © 2017 Elsevier Inc. All rights reserved.

Oxidative stress and antioxidant responses to increasing concentrations of trivalent chromium in the Andean crop species Chenopodium quinoa Willd.

PubMed

Scoccianti, Valeria; Bucchini, Anahi E; Iacobucci, Marta; Ruiz, Karina B; Biondi, Stefania

2016-11-01

Quinoa (Chenopodium quinoa Willd), an ancient Andean seed crop, exhibits exceptional nutritional properties and resistance to abiotic stress. The species' tolerance to heavy metals has, however, not yet been investigated nor its ability to take up and translocate chromium (Cr). This study aimed to investigate the metabolic adjustments occurring upon exposure of quinoa to several concentrations (0.01-5mM) of CrCl3. Young hydroponically grown plants were used to evaluate Cr uptake, growth, oxidative stress, and other biochemical parameters three and/or seven days after treatment. Leaves accumulated the lowest amounts of Cr, while roots and stems accumulated the most at low and at high metal concentrations, respectively. Fresh weight and photosynthetic pigments were reduced only by the higher Cr(III) doses. Substantially increased lipid peroxidation, hydrogen peroxide, and proline levels were observed only with 5mM Cr(III). Except for a significant decrease at day 7 with 5mM Cr(III), total polyphenols and flavonoids maintained control levels in Cr(III)-treated plants, whereas antioxidant activity increased in a dose-dependent manner. Maximum polyamine accumulation was observed in 1mM CrCl3-treated plants. Even though α- and γ-tocopherols also showed enhanced levels only with the 1mM concentration, tyrosine aminotransferase (TAT, EC 2.6.1.5) activity increased under Cr(III) treatment in a dose- and time-dependent manner. Taken together, results suggest that polyamines, tocopherols, and TAT activity could contribute to tolerance to 1mM Cr(III), but not to the highest concentration that, instead, generated oxidative stress. Copyright © 2016 Elsevier Inc. All rights reserved.

Signs of lateral transport of CO2 and CH4 in freshwater systems in boreal zone

NASA Astrophysics Data System (ADS)

Ojala, A.; Pumpanen, J. S.

2013-12-01

The numerous waterbodies and their riparian zones in the boreal zone are important to lateral carbon transport of terrestrial origin. These freshwater systems are also significant for carbon cycling on the landscape level. However, the lateral signals of carbon gases can be difficult to detect and thus, we used here different approaches to verify the phenomenon. We installed continuous measurement systems with CO2 probes in the riparian zone soil matrix around a small pristine headwater lake, in the lake, and in the outflowing stream and followed up the seasonal variation in CO2 concentration and in rain event-driven changes. We also used the probes in a second-order stream discharging a catchment of managed forest. The conventional weekly sampling protocol on water column CO2 and CH4 concentrations as well as gas fluxes was applied in three lakes surrounded by managed forests and some crop land but having different size and water quality. In two of the lakes most drastic changes in gas fluxes occurred not in spring but during or just after the summer rains when the clear water lake changed from a small carbon sink to carbon source and in the humic lake almost half of the CO2 and CH4 fluxes occurred during or just after the rainy period. Gas concentrations in the water columns revealed that the high surface water concentrations resulting in peak fluxes were not due to transport from hypolimnia rich in gases, but were due to soil processes and export from the flooded catchments. In the third lake, seasonal peak fluxes took place just after ice out, but again this was not a result of carbon gases accumulated under the ice, but gases originated from the surrounding catchment. In this lake, ca. 30 % of the annual CO2 flux occurred in May and 13 % of CH4 was emitted during one single week in May. In general, CH4 appeared as a good tracer for lateral transport. In the soil-lake-stream continuum, seasonal variation in CO2 was greatest and concentrations highest deep in the soil and in the lake itself, but also in the stream, especially further down from the lake. In the stream, the influence of the riparian zone superseded that of the lake at less than 150 m distance, which resulted in wider variation and higher concentrations of CO2. After a spell of heavy rain, the CO2 concentration in the soil increased and supposedly, a considerable amount of CO2 of terrestrial origin entered the lake annually. However, since the rain event was combined with exceptionally high winds mixing the water column, the riparian CO2 load was diluted and could not be properly tracked down. The second-order stream draining a small lake had an unresponsive catchment with high base flow contribution and the low flow was important for the total annual CO2 export. In general, CO2 export was controlled by runoff. There was no concentration-discharge relationship which was different from four other catchments in Canada, UK and Sweden. The only exception was snowmelt event in spring when CO2 concentrations were high. This high concentration could be tracked down in the downstream lake. The studies thus revealed the importance of hydrological events such as high spring discharge after snowmelt and extreme rain events in summer for lateral carbon gas transport.

Resource Directory: Migrant and Indian Exceptional Children.

ERIC Educational Resources Information Center

Indian Education Training, Inc., Albuquerque, NM.

Designed as a supplementary resource for special education directors and teachers, this directory covers a five state area which includes Arizona, California, New Mexico, Texas, and Washington, and concentrates on targeted resources for Indian and migrant children with exceptional needs. After general discussions of services available for migrant…

Changes of brain metabolite concentrations during maturation in different brain regions measured by chemical shift imaging.

PubMed

Bültmann, Eva; Nägele, Thomas; Lanfermann, Heinrich; Klose, Uwe

2017-01-01

We examined the effect of maturation on the regional distribution of brain metabolite concentrations using multivoxel chemical shift imaging. From our pool of pediatric MRI examinations, we retrospectively selected patients showing a normal cerebral MRI scan or no pathologic signal abnormalities at the level of the two-dimensional 1H MRS-CSI sequence and an age-appropriate global neurological development, except for focal neurological deficits. Seventy-one patients (4.5 months-20 years) were identified. Using LC Model, spectra were evaluated from voxels in the white matter, caudate head, and corpus callosum. The concentration of total N-acetylaspartate increased in all regions during infancy and childhood except in the right caudate head where it remained constant. The concentration of total creatine decreased in the caudate nucleus and splenium and minimally in the frontal white matter and genu. It remained largely constant in the parietal white matter. The concentration of choline-containing compounds had the tendency to decrease in all regions except in the parietal white matter where it remained constant. The concentration of myoinositol decreased slightly in the splenium and right frontal white matter, remained constant on the left side and in the caudate nucleus, and rose slightly in the parietal white matter and genu. CSI determined metabolite concentrations in multiple cerebral regions during routine MRI. The obtained data will be helpful in future pediatric CSI measurements deciding whether the ratios of the main metabolites are within the range of normal values or have to be considered as probably pathologic.

Trimester-Specific Changes in Maternal Thyroid Hormone, Thyrotropin, and Thyroglobulin Concentrations During Gestation: Trends and Associations Across Trimesters in Iodine Sufficiency

PubMed Central

Soldin, O.P.; Tractenberg, R.E.; Hollowell, J.G.; Jonklaas, J.; Janicic, N.; Soldin, S.J.

2013-01-01

Objectives To describe the interrelationships of thyroid functions based on trimester-specific concentrations in healthy, iodine-sufficient pregnant women across trimesters, and postpartum. Methods Circulating total 3,5,3′-triidothyronine (T3) and thyroxine (T4) concentrations were determined simultaneously using liquid chromatography tandem mass-spectrometry (LC/MS/MS). Free thyroxine (FT4), thyroid-stimulating hormone (TSH), and thyroglobulin (Tg) were measured using immunoassay techniques. Linear mixed effects models and correlations were calculated to determine trends and associations, respectively, in concentrations. Results and conclusions Trimester-specific T3, FT4, TSH, and Tg concentrations were significantly different between the first and third trimesters (all p < 0.05); second and third trimester values were not significantly different for FT4, TSH, and Tg (all p > 0.25) although T3 was significantly higher in the third, relative to the second trimester. T4 was not significantly different at any trimester (all p > 0.80). With two exceptions, analyte concentrations tended not to be correlated at each trimester and at 1-year postpartum. One exception was that T3 and T4 tended to be associated (all p < 0.05) at all time points except the third trimester (ρ = 0.239, p > 0.05). T4 and FT4 concentrations tended to correlate positively during pregnancy (ρ 0.361–0.382, all p < 0.05) but not postpartum (ρ = 0.179, p > 0.05). Trends suggest that trimester-specific measurements of T3, FT4, Tg, and possibly TSH are warranted. PMID:15650363

Quantification of selected volatile constituents and anions in Mexican Agave spirits (Tequila, Mezcal, Sotol, Bacanora).

PubMed

Lachenmeier, Dirk W; Sohnius, Eva-Maria; Attig, Rainer; López, Mercedes G

2006-05-31

A large collection (n = 95) of Mexican Agave spirits with protected appellations of origin (Tequila, Mezcal, Sotol, and Bacanora) was analyzed using ion and gas chromatography. Because of their production from oxalate-containing plant material, all Agave spirits contained significant concentrations of oxalate (0.1-9.7 mg/L). The two Tequila categories ("100% Agave" and "mixed") showed differences in the methanol, 2-/3-methyl-1-butanol, and 2-phenylethanol concentrations with lower concentrations in the mixed category. Mezcal showed no significant differences in any of the evaluated parameters that would allow a classification. Sotol showed higher nitrate concentrations and lower 2-/3-methyl-1-butanol concentrations. Bacanora was characterized by exceptionally high acetaldehyde concentrations and a relatively low ethyl lactate content. The methanol content was the most problematic compound regarding the Mexican standards: two Tequilas (4%), five Sotols (31%), and six Bacanoras (46%) had levels above the maximum methanol content of 300 g/hL of alcohol. In conclusion, the composition of Mexican Agave spirits was found to vary over a relatively large range.

A method to determine shear adhesive strength of fibrin sealants.

PubMed

Sierra, D H; Feldman, D S; Saltz, R; Huang, S

1992-01-01

The adhesive strength of fibrin sealants has not been rigorously evaluated to date. The adhesive strength of six different concentrations of cryoprecipitated fibrinogen as well as the commercially available fibrin tissue adhesive Tissucol was tested under controlled conditions utilizing split-thickness skin grafts as the test adherand. This test configuration permitted the modeling of bonding strength for attachment of skin grafts as well as incorporate established engineering test standards for adhesives. An increase in fibrin concentration corresponded with an increase in shear adhesive strength. No significant increases in adhesive strength were attained after 5 min of bonding for all tested concentrations, except for the commercial adhesive, which attained the adhesive strength of an equivalent concentration of cryoprecipitated adhesive after 90 min. The adhesive strength, however, was an order of magnitude less than reported values of the tensile strength of fibrin material for similar concentrations. Therefore, it is important that the surgeon use a sufficiently high fibrinogen concentration for the specific clinical indication. The method of fibrin sealant preparation and/or the compounding adjuncts appear to have an effect on the development of adhesive strength.

Laboratory investigations of the effects of nitrification-induced acidification on Cr cycling in vadose zone material partially derived from ultramafic rocks

USGS Publications Warehouse

Mills, Christopher T.; Goldhaber, Martin B.

2012-01-01

Sacramento Valley (California, USA) soils and sediments have high concentrations of Cr(III) because they are partially derived from ultramafic material. Some Cr(III) is oxidized to more toxic and mobile Cr(VI) by soil Mn oxides. Valley soils typically have neutral to alkaline pH at which Cr(III) is highly immobile. Much of the valley is under cultivation and is both fertilized and irrigated. A series of laboratory incubation experiments were conducted to assess how cultivation might impact Cr cycling in shallow vadose zone material from the valley. The first experiments employed low (7.1 mmol N per kg soil) and high (35 mmol N kg− 1) concentrations of applied (NH4)2SO4. Initially, Cr(VI) concentrations were up to 45 and 60% greater than controls in low and high incubations, respectively. After microbially-mediated oxidation of all NH4+, Cr(VI) concentrations dropped below control values. Increased nitrifying bacterial populations (estimated by measurement of phospholipid fatty acids) may have increased the Cr(VI) reduction capacity of the vadose zone material resulting in the observed decreases in Cr(VI). Another series of incubations employed vadose zone material from a different location to which low (45 meq kg− 1) and high (128 meq kg− 1) amounts of NH4Cl, KCl, and CaCl2 were applied. All treatments, except high concentration KCl, resulted in mean soil Cr(VI) concentrations that were greater than the control. High concentrations of water-leachable Ba2 + (mean 38 μmol kg− 1) in this treatment may have limited Cr(VI) solubility. A final set of incubations were amended with low (7.1 mmol N kg− 1) and high (35 mmol N kg− 1) concentrations of commercial liquid ammonium polyphosphate (APP) fertilizer which contained high concentrations of Cr(III). Soil Cr(VI) in the low APP incubations increased to a concentration of 1.8 μmol kg− 1 (5 × control) over 109 days suggesting that Cr(III) added with the APP fertilizer was more reactive than naturally-occurring soil Cr(III).

A preliminary assessment of PM(10) and TSP concentrations in Tuticorin, India.

PubMed

Sivaramasundaram, K; Muthusubramanian, P

2010-06-01

The respirable particulate matter (RPM; PM(10)) and total suspended particulate matter (TSP) concentrations in ambient air in Tuticorin, India, were preliminarily estimated. Statistical analyses on so-generated database were performed to infer frequency distributions and to identify dominant meteorological factor affecting the pollution levels. Both the RPM and TSP levels were well below the permissible limits set by the US Environmental Protection Agency. As expected, lognormal distribution always fit the data during the study period. However, fit with the normal was also acceptable except for very few seasons. The RPM concentrations ranged between 20.9 and 198.2 mug/m(3), while the TSP concentrations varied from 51.5 to 333.3 mug/m(3) during the study period. There was a better correlation between PM(10-100) and TSP concentrations than that of PM(10) (RPM) and TSP concentrations, but the correlation of RPM fraction was also acceptable. It was found that wind speed was the most important meteorological factor affecting the concentrations of the pollutants of present interest. Significant seasonal variations in the pollutant concentrations of present interest were found at 5% significance level except for TSP concentrations in the year 2006.

Neonatal systemic inflammation and the risk of low scores on measures of reading and mathematics achievement at age 10 years among children born extremely preterm.

PubMed

Leviton, Alan; Dammann, Olaf; Allred, Elizabeth N; Joseph, Robert M; Fichorova, Raina N; O'Shea, T Michael; Kuban, Karl C K

2018-05-01

Difficulties with reading and math occur more commonly among children born extremely preterm than among children born at term. Reasons for this are unclear. We measured the concentrations of 27 inflammatory-related and neurotrophic/angiogenic proteins (angio-neurotrophic proteins) in multiple blood specimens collected a week apart during the first postnatal month from 660 children born before the 28th week of gestation who at age 10 years had an IQ ≥ 70 and a Wechsler Individual Achievement Test 3rd edition (WIAT-III) assessment. We identified four groups of children, those who had a Z-score ≤ -1 on the Word Reading assessment only, on the Numerical Operations assessment only, on both of these assessments, and on neither, which served as the referent group. We then modeled the risk of each learning limitation associated with a top quartile concentration of each protein, and with high and lower concentrations of multiple proteins. The protein profile of low reading scores was confined to the third and fourth postnatal weeks when increased risks were associated with high concentrations of IL-8 and ICAM-1 in the presence of low concentrations of angio-neurotrophic proteins. The profile of low math scores was very similar, except it did not include ICAM-1. In contrast, the profile of low scores on both assessments was present in each of the first four postnatal weeks. The increased risks associated with high concentrations of TNF-α in the first two weeks and of IL-8 and ICAM-1 in the next two weeks were modulated down by high concentrations of angio-neurotrophic proteins. High concentrations of angio-neurotrophic proteins appear to reduce/moderate the risk of each learning limitation associated with systemic inflammation. The three categories of limitations have protein profiles with some similarities, and yet some differences, too. Copyright © 2018 ISDN. Published by Elsevier Ltd. All rights reserved.

Interannual (2009-2013) variability of winter-spring phytoplankton in the open South Adriatic Sea: Effects of deep convection and lateral advection

NASA Astrophysics Data System (ADS)

Ljubimir, Stijepo; Jasprica, Nenad; Čalić, Marijeta; Hrustić, Enis; Dupčić Radić, Iris; Car, Ana; Batistić, Mirna

2017-07-01

The South Adriatic (SA) is an entry point for water masses originating from the Ionian Sea (IS) and a place of dense water formation for the eastern Mediterranean deep circulation cell. Water masses, entering the SA in larger amount during the winter, show decadal variability explained by different circulating regimes (cyclonic and anticyclonic) in the IS, referred to as "Bimodal Oscillating System" (BiOS). Sampling station was situated in the South Adriatic Pit (SAP) with depth of 1200 m. Micro- and nano-phytoplankton abundances, community structure, chlorophyll a concentrations, physical and chemical properties are presented in the winter and spring months for five consecutive years (2009-2013) during different circulating regimes of BiOS. Vertical convective mixing was regularly observed in winter except in 2011 which had effect on nutrient availability and consequently on biomass of primary producers. Effect of strong vertical mixing in February 2012 resulted with exceptionally high phytoplankton abundance and chlorophyll a concentrations in March of 2012. Strong convective mixing resulted in higher diatom abundances, comparing to winter when mixing did not occur. No such bloom was observed during investigated spring.

Midkine and pleiotrophin concentrations in needle biopsies of breast and lung masses.

PubMed

Giamanco, Nicole M; Jee, Youn Hee; Wellstein, Anton; Shriver, Craig D; Summers, Thomas A; Baron, Jeffrey

2017-09-07

Midkine (MDK) and pleiotrophin (PTN) are two closely related heparin-binding growth factors which are overexpressed in a wide variety of human cancers. We hypothesized that the concentrations of these factors in washout of biopsy needles would be higher in breast and lung cancer than in benign lesions. Seventy subjects underwent pre-operative core needle biopsies of 78 breast masses (16 malignancies). In 11 subjects, fine needle aspiration was performed ex vivo on 7 non-small cell lung cancers and 11 normal lung specimens within surgically excised lung tissue. The biopsy needle was washed with buffer for immunoassay. The MDK/DNA and the PTN/DNA ratio in most of the malignant breast masses were similar to the ratios in benign masses except one lobular carcinoma in situ (24-fold higher PTN/DNA ratio than the average benign mass). The MDK/DNA and PTN/DNA ratio were similar in most malignant and normal lung tissue except one squamous cell carcinoma (38-fold higher MDK/DNA ratio than the average of normal lung tissue). Both MDK and PTN are readily measurable in washout of needle biopsy samples from breast and lung masses and levels are highly elevated only in a specific subset of these malignancies.

Heavy metal contamination from mining sites in South Morocco: monitoring metal content and toxicity of soil runoff and groundwater.

PubMed

El Khalil, Hicham; El Hamiani, Ouafae; Bitton, Gabriel; Ouazzani, Naaila; Boularbah, Ali

2008-01-01

The aim of the present work is the assessment of metal toxicity in runoff, in their contaminated soils and in the groundwater sampled from two mining areas in the region of Marrakech using a microbial bioassay MetPLATE. This bioassay is based on the specific inhibition of the beta-galactosidase enzyme of a mutant strain of Escherichia coli, by the metallic pollutants. The stream waters from all sampling stations in the two mines were all very toxic and displayed percent enzyme inhibition exceeding 87% except SWA4 and SWB1 stations in mine C. Their high concentrations of copper (Cu) and zinc (Zn) confirm the acute toxicity shown by MetPLATE. The pH of stream waters from mine B and C varied between 2.1 and 6.2 and was probably responsible for metal mobilization, suggesting a problem of acid mine drainage in these mining areas. The bioassay MetPLATE was also applied to mine tailings and to soils contaminated by the acidic waters. The results show that the high toxicity of these soils and tailings was mainly due to the relatively concentration of soluble Zn and Cu. The use of MetPLATE in groundwater toxicity testing shows that, most of the samples exhibited low metal toxicity (2.7-45.5% inhibition) except GW3 of the mine B (95.3% inhibition during the wet season and 82.9% inhibition during the dry season). This high toxicity is attributed to the higher than usual concentrations of Cu (189 microg Cu l(-1)) and Zn (1505 microg Zn l(-1)). These results show the potential risk of the contamination of different ecosystems situated to the vicinity of these two metalliferous sites. The general trend observed was an increase in metal toxicity measured by the MetPLATE with increasing total and mobile metal concentrations in the studied matrices. Therefore, the MetPLATE bioassay is a reliable and fast bioassay to estimate the metals toxicity in the aquatic and solids samples.

Facile Quantification and Identification Techniques for Reducing Gases over a Wide Concentration Range Using a MOS Sensor in Temperature-Cycled Operation.

PubMed

Schultealbert, Caroline; Baur, Tobias; Schütze, Andreas; Sauerwald, Tilman

2018-03-01

Dedicated methods for quantification and identification of reducing gases based on model-based temperature-cycled operation (TCO) using a single commercial MOS gas sensor are presented. During high temperature phases the sensor surface is highly oxidized, yielding a significant sensitivity increase after switching to lower temperatures (differential surface reduction, DSR). For low concentrations, the slope of the logarithmic conductance during this low-temperature phase is evaluated and can directly be used for quantification. For higher concentrations, the time constant for reaching a stable conductance during the same low-temperature phase is evaluated. Both signals represent the reaction rate of the reducing gas on the strongly oxidized surface at this low temperature and provide a linear calibration curve, which is exceptional for MOS sensors. By determining these reaction rates on different low-temperature plateaus and applying pattern recognition, the resulting footprint can be used for identification of different gases. All methods are tested over a wide concentration range from 10 ppb to 100 ppm (4 orders of magnitude) for four different reducing gases (CO, H₂, ammonia and benzene) using randomized gas exposures.

Facile Quantification and Identification Techniques for Reducing Gases over a Wide Concentration Range Using a MOS Sensor in Temperature-Cycled Operation

PubMed Central

Schultealbert, Caroline; Baur, Tobias; Schütze, Andreas; Sauerwald, Tilman

2018-01-01

Dedicated methods for quantification and identification of reducing gases based on model-based temperature-cycled operation (TCO) using a single commercial MOS gas sensor are presented. During high temperature phases the sensor surface is highly oxidized, yielding a significant sensitivity increase after switching to lower temperatures (differential surface reduction, DSR). For low concentrations, the slope of the logarithmic conductance during this low-temperature phase is evaluated and can directly be used for quantification. For higher concentrations, the time constant for reaching a stable conductance during the same low-temperature phase is evaluated. Both signals represent the reaction rate of the reducing gas on the strongly oxidized surface at this low temperature and provide a linear calibration curve, which is exceptional for MOS sensors. By determining these reaction rates on different low-temperature plateaus and applying pattern recognition, the resulting footprint can be used for identification of different gases. All methods are tested over a wide concentration range from 10 ppb to 100 ppm (4 orders of magnitude) for four different reducing gases (CO, H2, ammonia and benzene) using randomized gas exposures. PMID:29494545

40 CFR 97.71 - Initial certification and recertification procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Monitoring and Reporting § 97.71 Initial certification and recertification procedures. (a) The owner or... monitors, NOX concentration CEMS, or excepted monitoring systems under appendix E of part 75 of this... operator of such a unit that qualifies to use the low mass emissions excepted monitoring methodology under...

40 CFR 97.71 - Initial certification and recertification procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Monitoring and Reporting § 97.71 Initial certification and recertification procedures. (a) The owner or... monitors, NOX concentration CEMS, or excepted monitoring systems under appendix E of part 75 of this... operator of such a unit that qualifies to use the low mass emissions excepted monitoring methodology under...

Soil solution and sugar maple response to NH(4)NO (3) additions in a base-poor northern hardwood forest of Québec, Canada.

PubMed

Moore, Jean-David; Houle, Daniel

2009-08-01

Nitrogen additions (NH4NO3) at rates of three- and ten-fold ambient atmospheric deposition (8.5 kg ha(-1) year(-1)) were realised in an acid- and base-poor northern hardwood forest of Québec, Canada. Soil solution chemistry, foliar chemistry, crown dieback and basal area growth of sugar maple (Acer saccharum Marsh.) were measured. Except for a transitory increase of NO3 and NH4 concentrations, there was no persistent increase in their level in soil solution 3 years after N treatments, with the exception of one plot out of three, that received the highest N addition, beginning to show persistent and high NO3 concentrations after 2 years of N additions. Three years of N additions have significantly increased the N DRIS index of sugar maple but not N foliar concentration. Potassium, Ca and Mn foliar concentrations, as well as P and Ca DRIS indices, decreased in treated plots after 3 years. No treatment effect was observed for basal area growth and dieback rate. One unexpected result was the significant decrease in foliar Ca even in the treated plots that received low N rates, despite the absence of significant NO3-induced leaching of Ca. The mechanism responsible for the decrease in foliar Ca is not known. Our results, however, clearly demonstrate that increased N deposition at sites with low base saturation may affect Ca nutrition even when clear signs of N saturation are not observed.

Relationships between Boron concentrations and trout in the firehole river, Wyoming: Historical information and preliminary results of a field study

USGS Publications Warehouse

Meyer, J.S.; Boelter, A.M.; Woodward, D.F.; Goldstein, J.N.; Farag, A.M.; Hubert, W.A.

1998-01-01

The Firehole River (FHR) in Yellowstone National Park (YNP) is a world- renowned recreational fishery that predominantly includes rainbow trout (RBT, Oncorhynchus mykiss) and brown trout (BNT, Salmo trutta). The trout populations apparently are closed to immigration and have been self- sustaining since 1955. Inputs from hot springs and geysers increase the temperature and mineral content of the water, including elevating the boron (B) concentrations to a maximum of ~1 mg B/L. Both RBT and BNT reside in warm-water reaches, except when the water is extremely warm (???~25??C) during midsummer. They spawn in late fall and early winter, with documented spawning of BNT in the cold-water reach upstream from the Upper Geyser Basin and of RBT in the Lower Geyser Basin reach, where water temperatures presumably are the warmest; however, successful recruitment of RBT in waters containing ~1 mg B/L has not been demonstrated conclusively. Thus, we began investigating the relationships among temperature, B concentrations, other water-quality parameters, and the distribution and reproduction of trout in the FHR in spring 1997. However, atypical high water flows and concomitant lower than historical temperatures and B concentrations during summer 1997 preclude conclusions about avoidance of high B concentrations.

Heavy metal content of combustible municipal solid waste in Denmark.

PubMed

Riber, Christian; Fredriksen, Gry S; Christensen, Thomas H

2005-04-01

Data on the heavy metal composition of outlets from Danish incinerators was used to estimate the concentration of Zn, Cu, Pb, Cr, Ni, Cd, As and Hg in combustible waste (wet as received) at 14 Danish incinerators, representing about 80% of the waste incinerated in Denmark. Zn (1020 mg kg(-1)), Cu (620 mg kg(-1)) and Pb (370 mg kg(-1)) showed the highest concentration, whereas Hg (0.6 mg kg(-1)) showed the lowest concentration. The variation among the incinerators was in most cases within a factor of two to three, except for Cr that in two cases showed unexplained high concentrations. The fact that the data represent many incinerators and, in several cases, observations from a period of 4 to 5 years provides a good statistical basis for evaluating the content of heavy metals in combustible Danish waste. Such data may be used for identifying incinerators receiving waste with high concentrations of heavy metals suggesting the introduction of source control, or, if repeated in time, the data must also be used for monitoring the impacts of national regulation controlling heavy metals. It is recommended that future investigations consider the use of sample digestion methods that ensure complete digestion in order to use the data for determining the total heavy metal content of waste.

Geophagy by yellowstone grizzly bears

USGS Publications Warehouse

Mattson, D.J.; Green, G.I.; Swalley, R.

1999-01-01

We documented 12 sites in the Yellowstone ecosystem where grizzly bears (Ursus arctos horribilis) had purposefully consumed soil (an activity known as geophagy). We also documented soil in numerous grizzly bear feces. Geophagy primarily occurred at sites barren of vegetation where surficial geology had been modified by geothermal activity. There was no evidence of ungulate use at most sites. Purposeful consumption of soil by bears peaked first from March to May and again from August to October, synchronous with peaks in consumption of ungulate meat and mushrooms. Geophageous soils were distinguished from ungulate mineral licks and soils in general by exceptionally high concentrations of potassium (K) and high concentrations of magnesium (Mg) and sulphur (S). Our results do not support the hypotheses that bears were consuming soil to detoxify secondary compounds in grazed foliage, as postulated for primates, or to supplement dietary sodium, as known for ungulates. Our results suggest that grizzly bears could have been consuming soil as an anti-diarrheal.

Mycotoxin production by indoor molds.

PubMed

Fog Nielsen, Kristian

2003-07-01

Fungal growth in buildings starts at a water activity (a(w)) near 0.8, but significant quantities of mycotoxins are not produced unless a(w) reaches 0.95. Stachybotrys generates particularly high quantities of many chemically distinct metabolites in water-damaged buildings. These metabolites are carried by spores, and can be detected in air samples at high spore concentrations. Very little attention has been paid to major metabolites of Stachybotrys called spirocyclic drimanes, and the precise structures of the most abundant of these compounds are unknown. Species of Aspergillus and Penicillium prevalent in the indoor environment produce relatively low concentrations of mycotoxins, with the exception of sterigmatocystins that can represent up to 1% of the biomass of A. versicolor at a(w)'s close to 1. The worst-case scenario for homeowners is produced by consecutive episodes of water damage that promote fungal growth and mycotoxin synthesis, followed by drier conditions that facilitate the liberation of spores and hyphal fragments.

Characterization of Lactobacillus brevis L62 strain, highly tolerant to copper ions.

PubMed

Mrvčić, Jasna; Butorac, Ana; Solić, Ema; Stanzer, Damir; Bačun-Družina, Višnja; Cindrić, Mario; Stehlik-Tomas, Vesna

2013-01-01

Lactic acid bacteria (LAB) as starter culture in food industry must be suitable for large-scale industrial production and possess the ability to survive in unfavorable processes and storage conditions. Approaches taken to address these problems include the selection of stress-resistant strains. In food industry, LAB are often exposed to metal ions induced stress. The interactions between LAB and metal ions are very poorly investigated. Because of that, the influence of non-toxic, toxic and antioxidant metal ions (Zn, Cu, and Mn) on growth, acid production, metal ions binding capacity of wild and adapted species of Leuconostoc mesenteroides L3, Lactobacillus brevis L62 and Lactobacillus plantarum L73 were investigated. The proteomic approach was applied to clarify how the LAB cells, especially the adapted ones, protect themselves and tolerate high concentrations of toxic metal ions. Results have shown that Zn and Mn addition into MRS medium in the investigated concentrations did not have effect on the bacterial growth and acid production, while copper ions were highly toxic, especially in static conditions. Leuc. mesenteroides L3 was the most efficient in Zn binding processes among the chosen LAB species, while L. plantarum L73 accumulated the highest concentration of Mn. L. brevis L62 was the most copper resistant species. Adaptation had a positive effect on growth and acid production of all species in the presence of copper. However, the adapted species incorporated less metal ions than the wild species. The exception was adapted L. brevis L62 that accumulated high concentration of copper ions in static conditions. The obtained results showed that L. brevis L62 is highly tolerant to copper ions, which allows its use as starter culture in fermentative processes in media with high concentration of copper ions.

Platinum-group elements, S, Se and Cu in highly depleted abyssal peridotites from the Mid-Atlantic Ocean Ridge (ODP Hole 1274A): Influence of hydrothermal and magmatic processes

NASA Astrophysics Data System (ADS)

Marchesi, Claudio; Garrido, Carlos J.; Harvey, Jason; González-Jiménez, José María; Hidas, Károly; Lorand, Jean-Pierre; Gervilla, Fernando

2013-11-01

Highly depleted harzburgites and dunites were recovered from ODP Hole 1274A, near the intersection between the Mid-Atlantic Ocean Ridge and the 15°20'N Fracture Zone. In addition to high degrees of partial melting, these peridotites underwent multiple episodes of melt-rock reaction and intense serpentinization and seawater alteration close to the seafloor. Low concentrations of Se, Cu and platinum-group elements (PGE) in harzburgites drilled at around 35-85 m below seafloor are consistent with the consumption of mantle sulfides after high degrees (>15-20 %) of partial melting and redistribution of chalcophile and siderophile elements into PGE-rich residual microphases. Higher concentrations of Cu, Se, Ru, Rh and Pd in harzburgites from the uppermost and lowest cores testify to late reaction with a sulfide melt. Dunites were formed by percolation of silica- and sulfur-undersaturated melts into low-Se harzburgites. Platinum-group and chalcophile elements were not mobilized during dunite formation and mostly preserve the signature of precursor harzburgites, except for higher Ru and lower Pt contents caused by precipitation and removal of platinum-group minerals. During serpentinization at low temperature (<250 °C) and reducing conditions, mantle sulfides experienced desulfurization to S-poor sulfides (mainly heazlewoodite) and awaruite. Contrary to Se and Cu, sulfur does not record the magmatic evolution of peridotites but was mostly added in hydrothermal sulfides and sulfate from seawater. Platinum-group elements were unaffected by post-magmatic low-temperature processes, except Pt and Pd that may have been slightly remobilized during oxidative seawater alteration.

High resolution imaging of galaxy cores

NASA Technical Reports Server (NTRS)

Crane, P.; Stiavelli, M.; King, I. R.; Deharveng, J. M.; Albrecht, R.; Barbieri, C.; Blades, J. C.; Boksenberg, A.; Disney, M. J.; Jakobsen, P.

1993-01-01

Surface photometry data obtained with the Faint Object Camera of the Hubble Space Telescope in the cores of ten galaxies is presented. The major results are: (1) none of the galaxies show truly 'isothermal' cores, (2) galaxies with nuclear activity show very similar light profiles, (3) all objects show central mass densities above 10 exp 3 solar masses/cu pc3, and (4) four of the galaxies (M87, NGC 3862, NGC 4594, NGC 6251) show evidence for exceptional nuclear mass concentrations.

Effects of different sewage sludge applications on heavy metal accumulation, growth and yield of spinach (Spinacia oleracea L.).

PubMed

Eid, Ebrahem M; El-Bebany, Ahmed F; Alrumman, Sulaiman A; Hesham, Abd El-Latif; Taher, Mostafa A; Fawy, Khaled F

2017-04-03

In this study, we present the response of spinach to different amendment rates of sewage sludge (0, 10, 20, 30, 40 and 50 g kg -1 ) in a greenhouse pot experiment, where plant growth, biomass and heavy metal uptake were measured. The results showed that sewage sludge application increased soil electric conductivity (EC), organic matter, chromium and zinc concentrations and decreased soil pH. All heavy metal concentrations of the sewage sludge were below the permissible limits for land application of sewage sludge recommended by the Council of the European Communities. Biomass and all growth parameters (except the shoot/root ratio) of spinach showed a positive response to sewage sludge applications up to 40 g kg -1 compared to the control soil. Increasing the sewage sludge amendment rate caused an increase in all heavy metal concentrations (except lead) in spinach root and shoot. However, all heavy metal concentrations (except chromium and iron) were in the normal range and did not reach the phytotoxic levels. The spinach was characterized by a bioaccumulation factor <1.0 for all heavy metals. The translocation factor (TF) varied among the heavy metals as well as among the sewage sludge amendment rates. Spinach translocation mechanisms clearly restricted heavy metal transport to the edible parts (shoot) because the TFs for all heavy metals (except zinc) were <1.0. In conclusion, sewage sludge used in the present study can be considered for use as a fertilizer in spinach production systems in Saudi Arabia, and the results can serve as a management method for sewage sludge.

Mesquite Gum as a Novel Reducing and Stabilizing Agent for Modified Tollens Synthesis of Highly Concentrated Ag Nanoparticles

PubMed Central

Moreno-Trejo, Maira Berenice; Sánchez-Domínguez, Margarita

2016-01-01

The synthesis that is described in this study is for the preparation of silver nanoparticles of sizes ranging from 10 nm to 30 nm with a defined shape (globular), confirmed by UV-vis, SEM, STEM and DLS analysis. This simple and favorable one-step modified Tollens reaction does not require any special equipment or other stabilizing or reducing agent except for a solution of purified mesquite gum, and it produces aqueous colloidal dispersions of silver nanoparticles with a stability that exceeds three months, a relatively narrow size distribution, a low tendency to aggregate and a yield of at least 95% for all cases. Reaction times are between 15 min and 60 min to obtain silver nanoparticles in concentrations ranging from 0.1 g to 3 g of Ag per 100 g of reaction mixture. The proposed synthetic method presents a high potential for scale-up, since its production capacity is rather high and the methodology is simple. PMID:28773938

[Air pollution due to the burning of thermoplastics II (author's transl)].

PubMed

van Grimbergen, M; Reybrouck, G; van de Voorde, H

1975-03-01

Following on from the first publication, (12) concerning the burning of plastics, another 13 chemical pure polymers were burnt in an electric oven to determine the level of solid and gaseous air pollution caused by their stackgases. All 13 polymers are highly combustible but require different burning temperatures (300-900 degrees C) in order to be burnt completely (i.e. without ashrest). With the exception of PMMA and PTFE, all plastics leave a very heavy tar- and soot deposit after burning. At the other end of the scale, burning at low temperature (300 degrees C) gives rise to high concentrations of alipathic aldehyds. The pH of the exhaust-gases, dissolved in water, is neutral to strong acid (PTFE), and will cause a severe corrosion. The nitrogen-containing polymers pollute by forming cyanides, nitrogenoxides and ammonia. PTFE gives off high concentrations of fluorid into the air. PMMA decomposes in its monomer methylmethacrylate and forms large amounts of aliphatic aldehyds. ABS and SBR cause a styrene pollution.

Assessment of the performance of a compact concentric spectrometer system for Atmospheric Differential Optical Absorption Spectroscopy

NASA Astrophysics Data System (ADS)

Whyte, C.; Leigh, R. J.; Lobb, D.; Williams, T.; Remedios, J. J.; Cutter, M.; Monks, P. S.

2009-12-01

A breadboard demonstrator of a novel UV/VIS grating spectrometer has been developed based upon a concentric arrangement of a spherical meniscus lens, concave spherical mirror and curved diffraction grating suitable for a range of atmospheric remote sensing applications from the ground or space. The spectrometer is compact and provides high optical efficiency and performance benefits over traditional instruments. The concentric design is capable of handling high relative apertures, owing to spherical aberration and comma being near zero at all surfaces. The design also provides correction for transverse chromatic aberration and distortion, in addition to correcting for the distortion called "smile", the curvature of the slit image formed at each wavelength. These properties render this design capable of superior spectral and spatial performance with size and weight budgets significantly lower than standard configurations. This form of spectrometer design offers the potential for exceptionally compact instrument for differential optical absorption spectroscopy (DOAS) applications from LEO, GEO, HAP or ground-based platforms. The breadboard demonstrator has been shown to offer high throughput and a stable Gaussian line shape with a spectral range from 300 to 450 nm at 0.5 nm resolution, suitable for a number of typical DOAS applications.

Water quality and mass transport in four watersheds in eastern Puerto Rico: Chapter E in Water quality and landscape processes of four watersheds in eastern Puerto Rico

USGS Publications Warehouse

Stallard, Robert F.; Murphy, Sheila F.; Murphy, Sheila F.; Stallard, Robert F.

2012-01-01

Water quality of four small watersheds in eastern Puerto Rico has been monitored since 1991 as part of the U.S. Geological Survey's Water, Energy, and Biogeochemical Budgets program. These watersheds represent a montane, humid-tropical environment and differ in geology and land cover. Two watersheds are located on granitic rocks, and two are located on volcaniclastic rock. For each bedrock type, one watershed is covered with mature rainforest in the Luquillo Mountains, and the other watershed is undergoing reforestation after being affected by agricultural practices typical of eastern Puerto Rico. A subwatershed of the Icacos watershed, the Guabá, was also monitored to examine scaling effects. The water quality of the rivers draining forest, in the Icacos and Guabá (granitic watersheds) and Mameyes (a volcaniclastic watershed), show little contamination by human activities. The water is well oxygenated and has a nearly neutral pH, and nutrient concentrations are low. Concentrations of nutrients in the disturbed watersheds, the Cayaguás (granitic rock) and Canóvanas (volcaniclastic rock), are greater than in the forested watersheds, indicating some inputs from human activities. High in-stream productivity in the Canóvanas watershed leads to occasional oxygen and calcite supersaturation and carbon dioxide undersaturation. Suspended sediment concentrations in all watersheds are low, except during major storms. Most dissolved constituents derived from bedrock weathering or atmospheric deposition (including sodium, magnesium, calcium, silica, alkalinity, and chloride) decrease in concentration with increasing runoff, reflecting dilution from increased proportions of overland or near-surface flow. Strongly bioactive constituents (dissolved organic carbon, potassium, nitrate, ammonium ion, and phosphate) commonly display increasing concentration with increasing runoff, regardless of their ultimate origin (bedrock or atmosphere). The concentrations of many of the bioactive constituents eventually decrease at runoff rates greater than 3 to 10 millimeters per hour, presumably reflecting an increased relative contribution from overland flow. Sulfate behaves like the nonbioactive constituents in the Canóvanas, Cayaguás, and Mameyes watersheds but like a bioactive constituent in the Icacos and Guabá watersheds. Storms resulted in several anomalous sample compositions. Runoff waters from a number of storms - mostly hurricanes, but also other storms - have exceptionally high chloride concentrations, presumably resulting from windborne seasalt from the ocean, and low nitrate concentrations, reflecting a dominance of maritime air masses contributing moisture to the storms. High-potassium samples, without high chloride, are also associated with some smaller storms that followed Hurricane Georges in 1998; they are likely related to the breakdown of fallen vegetation. Finally, occasional low-silica events are observed in the Icacos and Guabá watersheds in the years prior to Hurricane Georges, but not after; this difference may be related to a change in hydrologic flow paths.

Measurement of radiation exposure of astronauts by radiochemical techniques

NASA Technical Reports Server (NTRS)

Brodzinski, R. L.

1972-01-01

Only two of the fecal specimens collected inflight during the Apollo 15 mission were returned for analysis. Difficulty in obtaining reasonably accurate radiation dose estimates based on the cosmogenic radionuclide content of the specimens was encountered due to the limited sampling. The concentrations of Na-22, K-40, Cr-51, Fe-59, and Cs-137 are reported. The concentrations of 24 major, minor, and trace elements in these two specimens were determined. Most concentrations are typical of those observed previously. Major exceptions are extremely low values for selenium and extraordinarily high values for rare earth elements. The net Po-210 activities in the Apollo 11 and 12 Solar Wind Composition foils and in the Apollo 8 and 12 spacecraft reflective coatings due to lunar exposure have been determined. Equilibrium concentrations of 0.082 + or - 0.012 disintegrations /sq cm sec of Rn-222 in the lunar atmosphere and 0.0238 + or - 0.0035 disintegrations /sq cm sec of Po-210 on the lunar surface have been calculated for Oceanus Procellarum.

Observation of radioactive iodine ((131)I, (129)I) in cropland soil after the Fukushima nuclear accident.

PubMed

Fujiwara, Hideshi

2016-10-01

During the early stages of the Fukushima nuclear accident, the temporal variations of (131)I deposited on the ground and of (131)I accumulated in cropland soil were monitored at a fixed location in Japan. Moreover, concentrations of long-lived radioactive iodine ((129)I) in atmospheric deposits and soil were measured to examine the feasibility of retrospectively reconstructing (131)I levels from the levels of accident-derived (129)I. The exceptionally high levels of (131)I in deposits and soil were attributed to rainfall-related deposition of radionuclides. In the crop field studied, the losses of deposited (131)I and (129)I due to volatilization were small. The atomic ratio (129)I/(131)I in the topsoil corresponded to the same ratio in deposits. The (131)I concentrations measured in the topsoil were very consistent with the (131)I concentrations reconstructed from the (129)I concentrations in the soil. Copyright © 2016 Elsevier B.V. All rights reserved.

The removal of microorganisms and organic micropollutants from wastewater during infiltration to aquifers after irrigation of farmland in the Tula Valley, Mexico.

PubMed

Chávez, Alma; Maya, Catalina; Gibson, Richard; Jiménez, Blanca

2011-05-01

The Tula Valley receives untreated wastewater from Mexico City for agricultural irrigation, half of which infiltrates to aquifers from where drinking water is extracted. Samples of wastewater and infiltrated water from three areas of the valley were analyzed for microorganisms, organic micropollutants, and some basic parameters. Concentrations of microorganisms in the infiltrated water were generally very low but the incidence of fecal coliforms (present in 68% of samples), somatic bacteriophages (36%), Giardia spp. (14%), and helminth eggs (8%) suggested a health risk. Organic micropollutants, often present at high concentrations in the wastewater, were generally absent from the infiltrated water except carbamazepine which was in 55% of samples (up to 193 ng/L). There was no correlation between carbamazepine concentrations and the presence of microorganisms but highest concentrations of carbamazepine and boron coincided. A treatment such as nanofiltration would be necessary for the infiltrated water to be a safe potable supply. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effect of natural and synthetic surfactants on crude oil biodegradation by indigenous strains.

PubMed

Tian, Wei; Yao, Jun; Liu, Ruiping; Zhu, Mijia; Wang, Fei; Wu, Xiaoying; Liu, Haijun

2016-07-01

Hydrocarbon pollution is a worldwide problem. In this study, five surfactants containing SDS, LAS, Brij 30, Tween 80 and biosurfactant were used to evaluate their effect on crude oil biodegradation. Hydrocarbon degrading bacteria were isolated from oil production water. The biosurfactant used was a kind of cyclic lipopeptide produced by Bacillus subtilis strain WU-3. Solubilization test showed all the surfactants could apparently increase the water solubility of crude oil. The microbial adhesion to the hydrocarbon (MATH) test showed surfactants could change cell surface hydrophobicity (CSH) of microbiota, depending on their species and concentrations. Microcalorimetric experiments revealed these surfactants exhibited toxicity to microorganisms at high concentrations (above 1 CMC), except for SDS which showed low antibacterial activity. Surfactant supplementation (about 0.1 and 0.2 CMC) could improve degradation rate of crude oil slightly, while high surfactant concentration (above 1 CMC) may decrease the degradation rate from 50.5% to 28.9%. Those findings of this work could provide guidance for the application of surfactants in bioremediation of oil pollution. Copyright © 2016 Elsevier Inc. All rights reserved.

Binational school-based monitoring of traffic-related air pollutants in El Paso, Texas (USA) and Ciudad Juárez, Chihuahua (México).

PubMed

Raysoni, Amit U; Sarnat, Jeremy A; Sarnat, Stefanie Ebelt; Garcia, Jośe Humberto; Holguin, Fernando; Luèvano, Silvia Flores; Li, Wen-Whai

2011-10-01

Paired indoor and outdoor concentrations of fine and coarse particulate matter (PM), PM2.5 reflectance [black carbon(BC)], and nitrogen dioxide (NO(2)) were determined for sixteen weeks in 2008 at four elementary schools (two in high and two in low traffic density zones) in a U.S.-Mexico border community to aid a binational health effects study. Strong spatial heterogeneity was observed for all outdoor pollutant concentrations. Concentrations of all pollutants, except coarse PM, were higher in high traffic zones than in the respective low traffic zones. Black carbon and NO(2) appear to be better traffic indicators than fine PM. Indoor air pollution was found to be well associated with outdoor air pollution, although differences existed due to uncontrollable factors involving student activities and building/ventilation configurations. Results of this study indicate substantial spatial variability of pollutants in the region, suggesting that children's exposures to these pollutants vary based on the location of their school. Copyright © 2011 Elsevier Ltd. All rights reserved.

POPs monitoring in Australia and New Zealand using plastic resin pellets, and International Pellet Watch as a tool for education and raising public awareness on plastic debris and POPs.

PubMed

Yeo, Bee Geok; Takada, Hideshige; Taylor, Heidi; Ito, Maki; Hosoda, Junki; Allinson, Mayumi; Connell, Sharnie; Greaves, Laura; McGrath, John

2015-12-15

Persistent organic pollutants (i.e. PCBs, DDTs, and HCHs) were analyzed along Australia and New Zealand North Island coastlines. PCB concentrations were high in urban areas (107-294 ng/g-pellet), with Sydney Harbour the most polluted. Hepta-chlorinated PCB was abundant, with ~30% in urban areas suggesting legacy pollution. DDT concentrations showed similar pattern except in rural agricultural sites, Taupo Bay and Ahipara, New Zealand (23 and 47 ng/g-pellet). p,p'-DDE predominance at these 2 sites suggested historical input; they also had high HCH concentrations (17 and 29 ng/g-pellet). The role of International Pellet Watch (IPW) in science communication was studied through feedbacks from IPW volunteers, case studies and examples. IPW data were categorized into understandable terms and tailored reports based on volunteers' backgrounds complemented with pollution maps. The effectiveness of IPW science communication has led to its use in awareness and education activities focusing on both POPs and plastic debris issues. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dominance of candidate Saccharibacteria in a membrane bioreactor treating medium age landfill leachate: Effects of organic load on microbial communities, hydrolytic potential and extracellular polymeric substances.

PubMed

Remmas, Nikolaos; Melidis, Paraschos; Zerva, Ioanna; Kristoffersen, Jon Bent; Nikolaki, Sofia; Tsiamis, George; Ntougias, Spyridon

2017-08-01

A membrane bioreactor (MBR), accomplishing high nitrogen removal efficiencies, was evaluated under various landfill leachate concentrations (50, 75 and 100% v/v). Proteinous and carbohydrate extracellular polymeric substances (EPS) and soluble microbial product (SMP) were strongly correlated (p<0.01) with organic load, salinity and NH 4 + -N. Exceptionally high β-glucosidase activities (6700-10,100Ug -1 ) were determined during MBR operation with 50% v/v leachate, as a result of the low organic carbon availability that extendedly induced β-glucosidases to breakdown the least biodegradable organic fraction. Illumina sequencing revealed that candidate Saccharibacteria were dominant, independently of the leachate concentration applied, whereas other microbiota (21.2% of total reads) disappeared when undiluted leachate was used. Fungal taxa shifted from a Saccharomyces- to a newly-described Cryptomycota-based community with increasing leachate concentration. Indeed, this is the first report on the dominance of candidate Saccharibacteria and on the examination of their metabolic behavior in a bioreactor treating real wastewater. Copyright © 2017 Elsevier Ltd. All rights reserved.

Persistent organic pollutants in the Atlantic and southern oceans and oceanic atmosphere.

PubMed

Luek, Jenna L; Dickhut, Rebecca M; Cochran, Michele A; Falconer, Renee L; Kylin, Henrik

2017-04-01

Persistent organic pollutants (POPs) continue to cycle through the atmosphere and hydrosphere despite banned or severely restricted usages. Global scale analyses of POPs are challenging, but knowledge of the current distribution of these compounds is needed to understand the movement and long-term consequences of their global use. In the current study, air and seawater samples were collected Oct. 2007-Jan. 2008 aboard the Icebreaker Oden en route from Göteborg, Sweden to McMurdo Station, Antarctica. Both air and surface seawater samples consistently contained α-hexachlorocyclohexane (α-HCH), γ-HCH, hexachlorobenzene (HCB), α-Endosulfan, and polychlorinated biphenyls (PCBs). Sample concentrations for most POPs in air were higher in the northern hemisphere with the exception of HCB, which had high gas phase concentrations in the northern and southern latitudes and low concentrations near the equator. South Atlantic and Southern Ocean seawater had a high ratio of α-HCH to γ-HCH, indicating persisting levels from technical grade sources. The Atlantic and Southern Ocean continue to be net sinks for atmospheric α-, γ-HCH, and Endosulfan despite declining usage. Copyright © 2017 Elsevier B.V. All rights reserved.

Cadmium contamination in orchard soils and fruit trees and its potential health risk in Guangzhou, China.

PubMed

Li, J T; Qiu, J W; Wang, X W; Zhong, Y; Lan, C Y; Shu, W S

2006-09-01

This study examines cadmium (Cd) contamination in orchard soils and fruit trees in Guangzhou, China, and assesses its potential health risk. Soils and tissues samples of three species of fruit trees were collected from three orchards. The average soil Cd concentration was 1.27, 1.84 and 0.68 mg/kg in orchards I, II, and III, respectively. The carambola (Averrhoa carambola) accumulated exceptionally high concentrations of Cd (7.57, 10.84, 9.01 and 2.15 mg/kg dw in root, twig, leaf and fruit, respectively), being 6.0-24 times and 4.0-10 times the corresponding tissue Cd in the longan (Dimocarpus longan) and wampee (Clausena lansium), respectively. Furthermore, all Cd concentrations (0.04-0.25 mg Cd/kg fw) of the fruits exceeded the tolerance limit of cadmium in foods of PR China (0.03 mg/kg fw). Our results indicate that the carambola tree has high Cd accumulation capacity and might be a Cd accumulator; and its fruit, among the three species of fruits studied, also poses the highest potential health risk to local residents.

Influence of compositional complexity on interdiffusion in Ni-containing concentrated solid-solution alloys

DOE PAGES

Jin, Ke; Zhang, Chuan; Zhang, Fan; ...

2018-03-07

To investigate the compositional effects on thermal-diffusion kinetics in concentrated solid-solution alloys, interdiffusion in seven diffusion couples with alloys from binary to quinary is systematically studied. The alloys with higher compositional complexity exhibit in general lower diffusion coefficients against homologous temperature, however, an exception is found that diffusion in NiCoFeCrPd is faster than in NiCoFeCr and NiCoCr. While the derived diffusion parameters suggest that diffusion in medium and high entropy alloys is overall more retarded than in pure metals and binary alloys, they strongly depend on specific constituents. The comparative features are captured by computational thermodynamics approaches using a self-consistentmore » database.« less

Chemical and physical quality of selected public water supplies in Florida, August-September 1976

USGS Publications Warehouse

Irwin, G.A.; Healy, Henry G.

1978-01-01

Results of a 1976 water-quality reconnaissance made by the U.S. Geological Survey indicated that, with few exceptions, all public water supplies in Florida are of high quality and meet the standards set forth in the National Interim Primary Drinking Water Regulations. Occasionally the concentrations of fluoride, turbidity, cadmium, chromium, and lead approximated, equaled, or exceeded maximum contaminant levels with exceedences occurring very infrequently. The pesticides 2,4-D and silvex, were detected in some public supplies throughout the State mainly in surface water. Although pesticides were not detected in concentrations approaching the maximum levels established in the regulations, their presence does signal that the activities of man are beginning to affect some water resources. (Woodard-USGS)

Volatile aromatic hydrocarbons and dicarboxylic acid concentrations in air at an urban site in the Southwestern US

NASA Astrophysics Data System (ADS)

Tran, Ngoc K.; Steinberg, Spencer M.; Johnson, Brian J.

Concentrations of benzene, toluene, ethylbenzene, o-xylene, and m- and p-xylene were measured at an urban sampling site in Las Vegas, NV by sorbent sampling followed by thermal desorption and determination by GC-PID. Simultaneously, measurements of oxalic, malonic, succinic, and adipic acids were made at the same site by collection on quartz filters, extraction, esterification, and determination by GC-FID. For the period from April 7, 1997 to June 11, 1997, 201 sets of hydrocarbon measurements and 99 sets of acid measurements were made. Additional measurements of dicarboxylic acids were made on samples that represented potential direct sources, e.g. green plants and road dust. Correlations between the hydrocarbon and CO concentrations (measured by the Clark County Health District at a nearby site) were highly significant and a strong negative correlation of hydrocarbon concentration with ozone concentration (also from the county site) was observed under quiescent atmospheric conditions. In general, dicarboxylic acid concentrations were well correlated with one another (with the exception of adipic acid) but not well correlated with hydrocarbon, CO, and ozone concentrations. Multiple sources and complex formation processes are indicated for the dicarboxylic acids.

Selenium and metal concentrations in waterbird eggs and chicks at Agassiz National Wildlife Refuge, Minnesota

USGS Publications Warehouse

Custer, T.W.; Custer, Christine M.; Eichhorst, B.A.; Warburton, D.

2007-01-01

Exceptionally high cadmium (Cd) and chromium (Cr) concentrations were reported in eggs, feathers, or livers of selected waterbird species nesting at Agassiz National Wildlife Refuge (Agassiz) in 1994. Ten- to 15-day-old Franklin's gull (Larus pipixcan), black-crowned night-heron (Nycticorax nycticorax), and eared grebe (Podiceps nigricollis) chicks were collected in 1998, 1999, and 2001 at Agassiz and analyzed for selenium (Se) and metals including Cd and Cr. Freshly laid eggs were collected in 2001 from Franklin's gull, black-crowned night-heron, eared grebe, and pied-billed grebe (Podilymbus podiceps) nests at Agassiz. Based on a multivariate analysis, the pattern of Se and metal concentrations differed among species for eggs, chick feathers, and chick livers. Low Cd and Cr concentrations were measured in eggs, chick livers, and chick feathers of all four species. Mercury concentrations in black-crowned night-heron and eared grebe eggs collected from Agassiz in 2001 were lower than concentrations reported in 1994. Se and metal concentrations, including Cd and Cr, in waterbird eggs and chicks collected at Agassiz in 1998, 1999, and 2001 were not at toxic levels. ?? 2007 Springer Science+Business Media, LLC.

Understanding Trends in Concentrated Poverty: 1980 to 2014*

PubMed Central

Iceland, John; Hernandez, Erik

2016-01-01

Trends in concentrated neighborhood poverty in the United States have been volatile over the past several decades. Using data from the 1980 to 2000 decennial census and the 2010-2014 American Community Survey, we examine the association between concentrated poverty across metropolitan areas in the United States and key proximate factors, including overall changes in poverty, racial residential segregation, and income segregation. One of our unique contributions is assessing the relative contribution of each of these to long-term trends in such poverty using a decomposition analysis. We find that changes in the segregation of the poor explained the largest share of the change in concentrated poverty over most of the time period, with the exception of the 1990s, where the plunge in both black and white poverty rates had the largest role in explaining the considerable decline in concentrated poverty in that decade for both groups. The association between racial segregation and black concentrated poverty is positive but weaker, indicating that without declines in black segregation, concentrated poverty would have been higher. Overall, growing income segregation, along with weak economic performance in recent years, have put more poor people at risk for living in high-poverty communities. PMID:28126115

Deer exposed to exceptionally high concentrations of lead near the continental mine in Idaho, USA

USGS Publications Warehouse

Beyer, W.N.; Gaston, G.; Brazzle, R.; O'Connell, A.F.; Audet, D.J.

2007-01-01

Habitat surrounding the inactive Continental Mine in northern Idaho, USA, supports bear (Ursus arctos, Ursus americanus), moose (Alces alces), elk (Cervus elaphus), woodland caribou (Rangifer tarandus caribou), and abundant mule (Odocoileus hemionus) and white-tailed deer (Odocoileus virginianus). Tailings on the mining site were capped and remediated in 2003 to reduce environmental exposure of surrounding soil and sediments of Blue Joe Creek, downslope of the mine. Before capping, the mean Pb concentration in deer pellets collected on-site was 920 mg/kg of Pb (dry wt). This exposure, if chronic, would be comparable to an exposure that could be lethal to cattle or horses. Surprisingly, the mean pellet Pb concentration of 950 mg/kg in 2004 was as high as it was before remediation, and it was related to a high rate of soil ingestion. Mean soil content of the pellets collected from the capped site in 2004 was 22% dry weight, estimated from the acid-insoluble ash, a marker of soil ingestion. Clumps of sand and bits of rock were observed inside some of the pellets, and Pb concentrations in the pellets were correlated (p < 0.05) with soil content. Although terrestrial risk assessments generally estimate exposure from diets and from incidentally ingested soil, the deer at this site were directly ingesting contaminated soil or mining waste. The mean Pb concentration of this ingested soil was estimated as 6,700 mg/kg and the maximum as 25,000 mg/kg, well above the Pb concentrations measured in the remediated cap. The deer seemed to be ingesting soil or mining waste from one or more small but highly contaminated sources located beyond the remediated cap.

Effects of landfill gas on subtropical woody plants

NASA Astrophysics Data System (ADS)

Chan, G. Y. S.; Wong, M. H.; Whitton, B. A.

1991-05-01

An account is given of the influence of landfill gas on tree growth in the field at Gin Drinkers' Bay (GDB) landfill, Hong Kong, and in the laboratory. Ten species ( Acacia confusa, Albizzia lebbek, Aporusa chinensis, Bombax malabaricum, Castanopsis fissa, Liquidambar formosana, Litsea glutinosa, Machilus breviflora, Pinus elliottii, and Tristania conferta), belonging to eight families, were transplanted to two sites, one with a high concentration of landfill gas in the cover soil (high-gas site, HGS) and the other with a relatively low concentration of gas (low-gas site, LGS). Apart from the gaseous composition, the general soil properties were similar. A strong negative correlation between tree growth and landfill gas concentration was observed. A laboratory study using the simulated landfill gas to fumigate seedlings of the above species showed that the adventitious root growth of Aporusa chinensis, Bombax malabaricum, Machilus breviflora, and Tristania confera was stimulated by the gas, with shallow root systems being induced. Acacia confusa, Albizzia lebbek, and Litsea glutinosa were gas-tolerant, while root growth of Castanopsis fissa, Liquidambar formosana, and Pinus elliottii was inhibited. In most cases, shoot growth was not affected, exceptions being Bombax malabaricum, Liquidambar formosana, and Tristania conferta, where stunted growth and/or reduced foliation was observed. A very high CO2 concentration in cover soil limits the depth of the root system. Trees with a shallow root system become very susceptible to water stress. The effects of low O2 concentration in soil are less important than the effects of high CO2 concentration. Acacia confusa, Albizzia lebbek, and Tristania conferta are suited for growth on subtropical completed landfills mainly due to their gas tolerance and/or drought tolerance.

Estimation of seasonal diurnal variations in primary and secondary organic carbon concentrations in the urban atmosphere: EC tracer and multiple regression approaches

NASA Astrophysics Data System (ADS)

Kim, Woogyung; Lee, Hanlim; Kim, Jhoon; Jeong, Ukkyo; Kweon, Jung

2012-09-01

In order to investigate seasonal and diurnal variation of primary organic carbon (POC) and secondary organic carbon (SOC) concentrations in a megacity, hourly measurements of particulate and gaseous pollutants were carried out in Seoul from January to December 2010. The EC Tracer Method (ECTM) and the Multiple Regression Method (MRM) have been used to estimate seasonal and diurnal concentrations of POC and SOC concentrations. Annual mean SOC concentrations estimated by ECTM (SOCECTM) and MRM (SOCMRM) accounted for 14.61 and 17.21% of TOC concentrations, respectively. Seasonal patterns in SOCMRM were comparable to those of SOCECTM, but the annual average SOCMRM was about 15% greater than that of SOCECTM. In spring, however, a large discrepancy was observed between SOCECTM and SOCMRM, which is thought to be due to a high ozone concentration and primary TOC/EC ratio. Regarding the annual mean diurnal characteristics, POC concentration showed peaks around 10:00 and 00:00 local time that were also observed in diurnal variations of TOC and EC concentrations. Annual mean SOC concentration, however, showed peaks at around 15:00. In the morning over all seasons, we found discrepancies between SOCECTM and SOCMRM due to overestimated SOCECTM concentration. The diurnal variations in SOC concentrations were found to have seasonal characteristics. The diurnal pattern of SOC concentration in spring was similar to that in autumn, and SOC concentrations in all seasons with the exception of winter showed a peak at around 15:00. In summer, however, the SOC concentration peak at around 15:00 was greater by 70%, 81%, and 54% than the peaks seen in spring, autumn, and winter, respectively, which could be explained by the high ozone concentration and strong UV radiation in summer. From 10:00 to 15:00 in summer, the average increase rates in SOCECTM and SOCMRM were 0.39 and 0.24 μg m-3 h-1, respectively. In winter, negligible diurnal variations of estimated SOC concentrations demonstrate that SOC formation is less active than in other seasons. The high concentration level of mean SOC in winter could be attributed to a low mixing height or stagnant atmospheric condition.

Regional differences in constituents of gall stones.

PubMed

Ashok, M; Nageshwar Reddy, D; Jayanthi, V; Kalkura, S N; Vijayan, V; Gokulakrishnan, S; Nair, K G M

2005-01-01

The pathogenesis of pigment and mixed gall stone formation remains elusive. The elemental constituents of gall stones from southern states of Tamil Nadu, Kerala and Karnataka have been characterized. Our aim was to determine the elemental concentration of representative samples of pigment, mixed and cholesterol gall stones from Andhra Pradesh using proton-induced X-ray emission (PIXE) using a 3 MV horizontal pelletron accelerator. Pigment gall stones had significantly high concentrations of copper, iron and lead; chromium was absent. Except for iron all these elements were significantly low in cholesterol gall stones and intermediate levels were seen in mixed gall stones. Highest concentrations of chromium was seen in cholesterol and titanium in mixed gall stones respectively; latter similar to other southern states. Arsenic was distinctly absent in cholesterol and mixed gall stones. The study has identified differences in elemental components of the gall stones from Andhra Pradesh.

Correlation of trace element concentrations between epidermis and internal organ tissues in Indo-Pacific humpback dolphins (Sousa chinensis).

PubMed

Sun, Xian; Yu, Ri-Qing; Zhang, Mei; Zhang, Xiyang; Chen, Xi; Xiao, Yousheng; Ding, Yulong; Wu, Yuping

2017-12-15

Trace element accumulation in the epidermis of cetaceans has been less studied. This study explored the feasibility of using epidermis as a surrogate tissue to evaluate internal contaminant burdens in Indo-Pacific humpback dolphin (Sousa chinensis). Eleven trace elements were analyzed in the epidermis, muscle and liver tissues from 46 individuals of dolphins stranded along the Pearl River Estuary (PRE) coast between 2007 and 2013. Trace elemental concentrations varied among the three tissues, generally with the highest concentrations found in liver tissues and lowest in the epidermis (except Zn, As, and Pb). Zn concentration in the epidermis was the highest among all tissues, indicating that Zn could be an important element for the epidermis physiology. High concentrations of Hg and Cr in liver were likely due to an excessive intake by dolphins which consumed high Hg and Cr contaminated fishes in the PRE. Hg concentrations in epidermis and muscle tissues were significantly higher in the females than in males. Concentrations of V and Pb in liver, Se and Cd in both muscle and liver, and As and Hg in all tissue samples showed significantly positive relationships with body length. Hepatic Cu concentrations were significantly negatively correlated with the body length. Hg and As concentrations in epidermis showed significantly positive correlations with those in liver tissues. Thus this study proposed that epidermis could be used as a non-invasive monitoring tissue to evaluate Hg and As bioaccumulation in internal tissues of Indo-Pacific humpback dolphins populations. Copyright © 2017 Elsevier B.V. All rights reserved.

Cadmium in the shore crab Carcinus maenas along the Norwegian coast: geographical and seasonal variation and correlation to physiological parameters.

PubMed

Knutsen, Heidi; Wiech, Martin; Duinker, Arne; Maage, Amund

2018-03-27

Previously, high concentrations of cadmium have been found in the hepatopancreas of the edible or brown crab (Cancer pagurus) sampled from positions north of about 67° N, compared to regions further south along the Norwegian coast, with no clear understanding why. In order to study a similar organism in the same ecosystem, the present study analyzed 210 shore crabs (Carcinus maenas) from four different locations along the Norwegian coast, two in the North and two in the South. The physiological variables size, sex, molting stage, hepatosomatic index, carapace color, and gonad maturation were registered, in attempt to explain the high inter-individual variation in cadmium levels in hepatopancreas. In contrast to the brown crabs, the shore crabs showed no clear geographical differences in cadmium concentrations. This indicates physiological differences between the two crab species. No clear and consistent correlations were found between cadmium levels and physiological parameters, except for sex, where cadmium concentration in hepatopancreas was twice as high in males compared to females. The cadmium levels also varied with season, with approximately 40 and 60% lower cadmium concentration in April than August for male and female shore crabs, respectively. None of the analyzed cadmium concentrations in muscle meat from claws exceeded EUs food safety limit, and low cadmium levels in soup prepared from shore crabs clearly indicated that this dish is not problematic regarding food safety.

Gas exchange, antioxidants and foliar injuries in saplings of a tropical woody species exposed to ozone.

PubMed

Pina, Juliana M; Moraes, Regina M

2010-05-01

Ozone (O(3)) reaches phytotoxical concentrations in the tropics, but the sensitivity of tropical plant species to O(3) remains unknown. Visible foliar injuries, carbon assimilation (A(sat)), stomatal conductance, superoxide dismutase enzyme (SOD) activity and ascorbic acid concentration (AA) were evaluated in different-aged leaves of Psidium guajava 'Paluma' saplings. We hypothesized that the old leaves are less capable of combating the stress induced by O(3) and hence exhibit more severe leaf injuries. Three O(3) exposure experiments were performed with 'Paluma' saplings in sites with high O(3) concentration and also under filtered air conditions. The exposure experiments corresponding to the seasons spring/2006, summer and autumn/2007. The decrease of A(sat) was greater in old leaves of saplings exposed to O(3), except in the second experiment, when the AA concentrations were more pronounced than in the other experiments. In second experiment, O(3) uptake was similar to that of the first experiment, but the injuries were less severe, probably due to the high AA concentrations. It was not possible to identify a pattern of superoxide dismutase enzyme (SOD) activity due to the high variability in the results from O(3) exposed and reference saplings. O(3) uptake/A(sat) was higher in leaves exhibiting greater injury, suggesting that decrease in A(sat) may have been the main feature associated with the visible foliar symptons. Copyright 2009 Elsevier Inc. All rights reserved.

Solvothermal crystallization of nanocrystals of metal oxides

NASA Astrophysics Data System (ADS)

Furukawa, S.; Amino, H.; Iwamoto, S.; Inoue, M.

2008-07-01

Solvothermal crystallization of the hydroxide gels obtained by hydrolysis of alkoxides (Zr, Ta, Nb, ln, Sn, Ti and Al) was examined. Nanocrystals having high surface areas (SBET > 170 m2 g-1) were obtained except for the product derived from indium isopropoxide. The effect of water in organic solvent upon the crystallinity of the product was investigated. The increase in the activity of water by using high concentration of alkoxide or intentional addition of water to the solvothermal medium led to crystal growth of the products. In contrast, decrease in activity of water by adding ethylene glycol before solvothermal treatment caused a decrease in crystallinity of the product.

Plasticity of trophic interactions among sharks from the oceanic south-western Indian Ocean revealed by stable isotope and mercury analyses

NASA Astrophysics Data System (ADS)

Kiszka, Jeremy J.; Aubail, Aurore; Hussey, Nigel E.; Heithaus, Michael R.; Caurant, Florence; Bustamante, Paco

2015-02-01

Sharks are a major component of the top predator guild in oceanic ecosystems, but the trophic relationships of many populations remain poorly understood. We examined chemical tracers of diet and habitat (δ15N and δ13C, respectively) and total mercury (Hg) concentrations in muscle tissue of seven pelagic sharks: blue shark (Prionace glauca), short-fin mako shark (Isurus oxyrinchus), oceanic whitetip shark (Carcharhinus longimanus), scalloped hammerhead shark (Sphyrna lewini), pelagic thresher shark (Alopias pelagicus), crocodile shark (Pseudocarcharias kamoharai) and silky shark (Carcharhinus falciformis), from the data poor south-western tropical Indian Ocean. Minimal interspecific variation in mean δ15N values and a large degree of isotopic niche overlap - driven by high intraspecific variation in δ15N values - was observed among pelagic sharks. Similarly, δ13C values of sharks overlapped considerably for all species with the exception of P. glauca, which had more 13C-depleted values indicating possibly longer residence times in purely pelagic waters. Geographic variation in δ13C, δ15N and Hg were observed for P. glauca and I. oxyrinchus. Mean Hg levels were similar among species with the exception of P. kamoharai which had significantly higher Hg concentrations likely related to mesopelagic feeding. Hg concentrations increased with body size in I. oxyrinchus, P. glauca and C. longimanus. Values of δ15N and δ13C varied with size only in P. glauca, suggesting ontogenetic shifts in diets or habitats. Together, isotopic data indicate that - with few exceptions - variance within species in trophic interactions or foraging habitats is greater than differentiation among pelagic sharks in the south-western Indian Ocean. Therefore, it is possible that this group exhibits some level of trophic redundancy, but further studies of diets and fine-scale habitat use are needed to fully test this hypothesis.

Exceptionally fast water desalination at complete salt rejection by pristine graphyne monolayers.

PubMed

Xue, Minmin; Qiu, Hu; Guo, Wanlin

2013-12-20

Desalination that produces clean freshwater from seawater holds the promise of solving the global water shortage for drinking, agriculture and industry. However, conventional desalination technologies such as reverse osmosis and thermal distillation involve large amounts of energy consumption, and the semipermeable membranes widely used in reverse osmosis face the challenge to provide a high throughput at high salt rejection. Here we find by comprehensive molecular dynamics simulations and first principles modeling that pristine graphyne, one of the graphene-like one-atom-thick carbon allotropes, can achieve 100% rejection of nearly all ions in seawater including Na(+), Cl(-), Mg(2+), K(+) and Ca(2+), at an exceptionally high water permeability about two orders of magnitude higher than those for commercial state-of-the-art reverse osmosis membranes at a salt rejection of ~98.5%. This complete ion rejection by graphyne, independent of the salt concentration and the operating pressure, is revealed to be originated from the significantly higher energy barriers for ions than for water. This intrinsic specialty of graphyne should provide a new possibility for the efforts to alleviate the global shortage of freshwater and other environmental problems.

No Difference in Perceived Intensity of Linoleic Acid in the Oral Cavity between Obese and Nonobese Individuals.

PubMed

Tucker, Robin M; Nuessle, Tiffany M; Garneau, Nicole L; Smutzer, Gregory; Mattes, Richard D

2015-10-01

Findings from studies examining interactions between fat taste and dietary fat intake or body weight are mixed. A convenience sample of 735 visitors to the Denver Museum of Nature & Science ≥8 years old rated the taste intensity of edible taste strips impregnated with varying concentrations (%v/v) of linoleic acid (LA) (blank = 0.0, low = 0.06, medium = 0.15, high = 0.38). Percent body fat (BF%) was measured using bioelectrical impedance. Fat taste intensity was rated as significantly different across all concentrations (P < 0.001) except between the blank and low concentrations (P = 0.1). Ratings increased monotonically across concentrations. Children (<18 years; N = 180) rated all concentrations as more intense than adults (P < 0.001 for all). Women and girls rated the highest concentration as more intense than men and boys (P < 0.02 for all). BF% was not correlated with fat taste intensity ratings. Self-reported dietary intake indicated that obese individuals' intensity ratings for medium and high concentrations of LA were inversely related to recent mono- and poly-unsaturated fat exposure (r = -0.19 to -0.27; P < 0.03 for all). No such associations were observed in the nonobese group. Findings suggest that factors other than simple adiposity status influence fat taste intensity ratings, and that participants in fat taste studies should receive standardized meals prior to testing. © The Author 2015. Published by Oxford University Press.

Physiological effects of autotoxicity due to DHAP stress on Picea schrenkiana regeneration

PubMed Central

Yang, Li; Ruan, Xiao; Jiang, Dean; Zhang, Jianhong; Pan, Cunde; Wang, Qiang

2017-01-01

Picea Schrenkiana as one of the most important zonal vegetation was an endemic species in Middle Asia. Natural regeneration of P. Schrenkiana is a long existing problem troubling scientists. The autotoxicity of 3,4-dihydroxy-acetophenone (DHAP) was found to be a causative factor causing the failure of P. Schrenkiana natural regeneration. The effects of concentrations of DHAP treatment on the viability of root cell, activities of antioxidant enzymes and levels of P. Schrenkiana phytohormones were performed to disclose the physiological mechanism of DHAP autotoxicity. It was observed that high concentration of DHAP could inhibit the seed germination and seedling growth, but had a hormesis at low concentrations. Analyses showed that the root cells significantly lost their viability treated with high DHAP. The enzymes activities of seedlings were significantly stimulated by the treatment of 0.5 mM DHAP to give a transient increase and then decrease as DHAP concentration increased to 1.0 mM except for GR (glutathione reductase) in which DHAP treatment had little effect on its activity. Comparing with the control, an increase in the levels of phytohormones ZT (zeatin), GA3 (gibberellic acid) and IAA (indole acetic acid) was induced by the treatment of DHAP at low concentrations (0.1–0.25 mM), but the significant deficiency was found treated by high concentrations (0.5–1.0 mM). In addition, the ABA (abscisic acid) level increased in all experimental observations. These results suggested that DHAP significantly affected indices of growth and physiology, and provided some new information about different effect in P. Schrenkiana treated with DHAP. PMID:28481896

Determination of radioactivity levels and heavy metal concentrations in seawater, sediment and anchovy (Engraulis encrasicolus) from the Black Sea in Rize, Turkey.

PubMed

Baltas, Hasan; Kiris, Erkan; Sirin, Murat

2017-03-15

Seawater, sediment and fish (anchovy) samples consumed in the Rize province of the Eastern Black Sea region of Turkey were collected from five different stations. The radioactivity levels ( 226 Ra, 232 Th, 40 K and 137 Cs) were determined in all the samples using a high-purity germanium detector. While 226 Ra, 232 Th and 40 K radionuclides were detected in all samples, the radionuclide concentration of 137 Cs, except for the sediment samples (mean activity is 9±1.4Bqkg -1 ), was not detected for the seawater and fish samples. The total annual effective dose rates from the ingestion of these radionuclides for fish were calculated using the measured activity concentrations in radionuclides and their ingested dose conversion factor. Also, the concentrations of some heavy metals in all the samples were determined. The activity and heavy metal concentration values that were determined for the seawater, sediment and fish samples were compared among the locations themselves and with literature values. Copyright © 2017 Elsevier Ltd. All rights reserved.

Rare earths and other trace elements in Apollo 14 samples.

NASA Technical Reports Server (NTRS)

Helmke, P. A.; Haskin, L. A.; Korotev, R. L.; Ziege, K. E.

1972-01-01

REE and other trace elements have been determined in igneous rocks 14053, 14072, and 14310, in breccias 14063 and 14313, and in fines 14163. All materials analyzed have typical depletions of Eu except for feldspar fragments from the breccias and igneous fragments from 14063. Igneous rocks 14072 and 14053 have REE concentrations very similar to Apollo 12 basalts; 14310 has the highest REE concentrations yet observed for a large fragment of lunar basalt. The effects of crystallization of a basaltic liquid as a closed system on the concentrations of Sm and Eu in feldspar are considered. Small anorthositic fragments may have originated by simple crystallization from very highly differentiated basalt (KREEP) or by closed-system crystallization in a less differentiated starting material. Application of independent models of igneous differentiation to Sm and Eu in massive anorthosite 15415 and to Sm and Eu in lunar basalts suggests a common starting material with a ratio of concentrations of Sm and Eu about the same as that in chondrites and with concentrations of those elements about 15 times enriched over chondrites.

Fragments of quartz monzodiorite and felsite in Apollo 14 soil particles

NASA Technical Reports Server (NTRS)

Jolliff, B. L.

1991-01-01

Samples of 'evolved' lithologies, felsite, quartz monzodiorite (QMD), and whitlockite-rich quartz monzodiorite, were identified compositionally and petrographically among 2-4-mm soil particles from Apollo 14. Fragments of QMD were found to be extremely rare in the Apollo 14 samples. Felsite is similar to previously reported samples. QMD 14161,7069 is similar to 15405 QMD and has ITE concentrations in KREEP-like concentration ratios of about twice the ITE concentrations of average high-K KREEP. QMD cumulate has the highest measured REE concentrations of any lunar sample to date with the exception of individual whitlockite grains. Felsite and whitlockite-rich lithologies appear to be petrogenetically related and have complementary compositions representing separated fractions of the QMD or KREEP-like parental melt. Felsite is a silica-rich fraction of the residual liquid or it is a derivative of the silica-rich fraction. Felsite or lunar granite of this type results from residual liquid separation following crystal-liquid separation of a QMD-like parent melt with concentration ratios of ITEs similar to those of KREEP.

Can we predict uranium bioavailability based on soil parameters? Part 1: effect of soil parameters on soil solution uranium concentration.

PubMed

Vandenhove, H; Van Hees, M; Wouters, K; Wannijn, J

2007-01-01

Present study aims to quantify the influence of soil parameters on soil solution uranium concentration for (238)U spiked soils. Eighteen soils collected under pasture were selected such that they covered a wide range for those parameters hypothesised as being potentially important in determining U sorption. Maximum soil solution uranium concentrations were observed at alkaline pH, high inorganic carbon content and low cation exchange capacity, organic matter content, clay content, amorphous Fe and phosphate levels. Except for the significant correlation between the solid-liquid distribution coefficients (K(d), L kg(-1)) and the organic matter content (R(2)=0.70) and amorphous Fe content (R(2)=0.63), there was no single soil parameter significantly explaining the soil solution uranium concentration (which varied 100-fold). Above pH=6, log(K(d)) was linearly related with pH [log(K(d))=-1.18 pH+10.8, R(2)=0.65]. Multiple linear regression analysis did result in improved predictions of the soil solution uranium concentration but the model was complex.

Occurrence of organotin compounds in river sediments under the dynamic water level conditions in the Three Gorges Reservoir Area, China.

PubMed

Gao, Jun-Min; Zhang, Ke; Chen, You-Peng; Guo, Jin-Song; Wei, Yun-Mei; Jiang, Wen-Chao; Zhou, Bin; Qiu, Hui

2015-06-01

The Three Gorges Project is the largest hydro project in the world, and the water level of the Three Gorges Reservoir (TGR) is dynamic and adjustable with the aim of flood control and electrical power generation. It is necessary to investigate the pollutants and their underlying contamination processes under dynamic water levels to determine their environmental behaviors in the Three Gorges Reservoir Area (TGRA). Here, we report the assessment of organotin compounds (OTs) pollution in the river sediments of the TGRA. Surface sediment samples were collected in the TGRA at low and high water levels. Tributyltin (TBT), triphenyltin (TPhT), and their degradation products in sediments were quantified by gas chromatography-mass spectrometry. Butyltins (BTs) and phenyltins (PhTs) were detected in sediments, and BTs predominated over PhTs in the whole study area under dynamic water level conditions. The concentrations of OTs in sediments varied markedly among locations, and significant concentrations were found in river areas with high levels of boat traffic and wastewater discharge. Sediments at all stations except Cuntan were lightly contaminated with TBT, and total organic carbon (TOC) was a significant factor affecting the fate of TBT in the TGRA. The butyltin and phenyltin degradation indices showed no recent inputs of TBT or TPhT into this region, with the exception of fresh TPhT input at Xiakou Town. Shipping activity, wastewater discharge, and agriculture are the most likely sources of OTs in the TGRA.

Physical properties and solubility parameters of 1-ethyl-3-methylimidazolium based ionic liquids/DMSO mixtures at 298.15 K

NASA Astrophysics Data System (ADS)

Saba, H.; Yumei, Z.; Huaping, W.

2015-12-01

Densities, refractive indices, conductivities and viscosities of binary mixtures of 1-ethyl-3-methylimidazolium-based ionic liquids (ILs) with dimethyl sulfoxide at 298.15 K are reported. Excess molar volumes have been calculated from experimental data and were fitted with Redlich-Kister equation. The density and refractive index were found to increase with increasing concentration in all cases except [EMIM]COOH. The free mobility of ions has found to enhance conductivity and decrease viscosity to varying extent in all mixtures being studied. It has been observed that solubility parameters, dielectric constants and nature of anions of ILs being used play a vital role in determining the subsequent characteristics. As DMSO has high dielectric constant therefore, it was able to form interactions with most of ILs except with [EMIM]COOH due to anomalous nature of anion.

Assessment of metal and nutrient concentrations in river water and sediment collected from the cities in the Pearl River Delta, South China.

PubMed

Cheung, K C; Poon, B H T; Lan, C Y; Wong, M H

2003-09-01

The effects of anthropogenic activities, industrialization and urbanization on the accumulation of heavy metals and nutrients in sediments and water of rivers in the Pearl River Delta region were examined. Most sediments were seriously contaminated with Cd, Pb, and Zn in accordance with the classification by Hong Kong Environmental Protection Department. Total phosphorus (P) and nitrogen (N) concentrations in sediments ranged from 0.02% to 0.12% and 0.06% to 0.64%, respectively. High carbon (C), N, P and sulphur (S) levels at Yuen Long Creek were related to the discharge of industrial effluents along the river. The enrichment of P and ammoniacal-nitrogen (NH4+-N) in water were obvious. For most sites, the P concentration exceeded 0.1 mg/l, which is the recommended concentration in flowing water to encourage excessive growth of aquatic plants. Nine out of the 16 sites studied had NH4+-N concentration over 2 mg/l. The rivers in the south of Deep Bay (Hong Kong) had high nutrient exports compared with the rivers in the east region and western oceanic water. The concentrations of nitrate-nitrogen NO3--N in surface water were under the maximum contaminant level in public drinking water supplies (10 mg/l) except for one site. Although the concentrations of heavy metals in overlying water were low, their accumulations were significant. High contents of nickel (Ni) and zinc (Zn) in water were found at certain locations, suggesting the occurrence of some local contamination. These preliminary results indicated that river and sediment transported pollutants is likely one of the factors for the water quality degradation of Deep Bay water.

Arsenic speciation in fish and shellfish from the North Sea (Southern bight) and Açu Port area (Brazil) and health risks related to seafood consumption.

PubMed

Gao, Yue; Baisch, Paulo; Mirlean, Nicolai; Rodrigues da Silva Júnior, Flavio Manoel; Van Larebeke, Nik; Baeyens, Willy; Leermakers, Martine

2018-01-01

In North Sea and Port Açu (Brazil) coastal areas, high arsenic (As) concentrations were observed in water, soil and sediments. Therefore, the impact of this contamination on fish and shellfish species bought from local fishermen was studied. Total As was assessed with ICP-OES (Brazil) and ICP-MS (North Sea) after microwave digestion. Toxic As was assessed with liquid chromatography-ICP-MS (Brazil) and hydride generation-atomic fluorescence spectrometry (North Sea). All analytical methods comply with Quality Assurance/Quality Control procedures. Several fish species have average Total As concentrations above 1 μg g-1 wet weight (ww), but the highest concentrations are found in less spotted dogfish, lemon sole and whelks from the North Sea, with respectively 50, 49 and 50 μg g-1 ww. High Total As concentrations correspond to high Toxic As concentrations, except for scallops having increased Toxic As concentrations. Toxic As fractions are highest in scallops (almost 10%) but rarely exceeds 2% in all other species. Liver samples were only analyzed in ray, dogfish and catfish and their Toxic As fractions are between 2 and 4 times higher than in muscle. For a consumption of 150 g of seafood, only 3 samples exceed the provisional total daily intake of 2 μg kg-1 bw, however, cancer risks are non-negligible. Using mean Toxic As concentrations for each of the different fish and shellfish species studied, Lifetime Cancer Risk values at the actual global seafood consumption rate of 54 g day-1 are above 10-4 for whelks, scallops, dogfish, ray and lemon sole. Copyright © 2017 Elsevier Ltd. All rights reserved.

Seasonal fate and gas/particle partitioning of semi-volatile organic compounds in indoor and outdoor air

NASA Astrophysics Data System (ADS)

Moreau-Guigon, Elodie; Alliot, Fabrice; Gaspéri, Johnny; Blanchard, Martine; Teil, Marie-Jeanne; Mandin, Corinne; Chevreuil, Marc

2016-12-01

Fifty-eight semi-volatile organic compounds (SVOCs) were investigated simultaneously in three indoor (apartment, nursery and office building) and one outdoor environment in the centre of Paris (France). All of these compounds except tetrabromobisphenol A were quantified in the gaseous and particulate phases in all three environments, and at a frequency of 100% for the predominant compounds of each SVOC class. Phthalic acid esters (PAEs) were the most abundant group (di-iso-butyl phthalate: 29-661 ng m-3, diethyl phthalate: 15-542 ng m-3), followed by 4-nonylphenol (1.4-81 ng m-3), parabens (methylparaben: 0.03-2.5 ng m-3), hexachlorobenzene (HCB) (0.002-0.26 ng m-3) and pentachlorobenzene (PeCB) (0.001-0.23 ng m-3). Polycyclic aromatic hydrocarbons (as ∑8PAHs) ranged from 0.17 to 5.40 ng m-3, polychlorinated biphenyls (as ∑7PCBi) from 0.06 to 4.70 ng.m3 and polybromodiphenyl ethers (as ∑8PBDEs) from 0.002 to 0.40 ng m-3. For most pollutants, significantly higher concentrations were observed in the nursery compared to the apartment and office. Overall, the indoor air concentrations were up to ten times higher than outdoor air concentrations. Seasonal variations were observed for PAEs, PCBs and PAHs. SVOCs were predominantly identified in the gaseous phase (>90%), except for some high-molecular-weight PAEs, PAHs and PCBs.

Measurement of tissue optical properties with optical coherence tomography: Implication for noninvasive blood glucose concentration monitoring

NASA Astrophysics Data System (ADS)

Larin, Kirill V.

Approximately 14 million people in the USA and more than 140 million people worldwide suffer from diabetes mellitus. The current glucose sensing technique involves a finger puncture several times a day to obtain a droplet of blood for analysis. There have been enormous efforts by many scientific groups and companies to quantify glucose concentration noninvasively using different optical techniques. However, these techniques face limitations associated with low sensitivity, accuracy, and insufficient specificity of glucose concentrations over a physiological range. Optical coherence tomography (OCT), a new technology, is being applied for noninvasive imaging in tissues with high resolution. OCT utilizes sensitive detection of photons coherently scattered from tissue. The high resolution of this technique allows for exceptionally accurate measurement of tissue scattering from a specific layer of skin compared with other optical techniques and, therefore, may provide noninvasive and continuous monitoring of blood glucose concentration with high accuracy. In this dissertation work I experimentally and theoretically investigate feasibility of noninvasive, real-time, sensitive, and specific monitoring of blood glucose concentration using an OCT-based biosensor. The studies were performed in scattering media with stable optical properties (aqueous suspensions of polystyrene microspheres and milk), animals (New Zealand white rabbits and Yucatan micropigs), and normal subjects (during oral glucose tolerance tests). The results of these studies demonstrated: (1) capability of the OCT technique to detect changes in scattering coefficient with the accuracy of about 1.5%; (2) a sharp and linear decrease of the OCT signal slope in the dermis with the increase of blood glucose concentration; (3) the change in the OCT signal slope measured during bolus glucose injection experiments (characterized by a sharp increase of blood glucose concentration) is higher than that measured in the glucose clamping experiments (characterized by slow, controlled increase of the blood glucose concentration); and (4) the accuracy of glucose concentration monitoring may substantially be improved if optimal dimensions of the probed skin area are used. The results suggest that high-resolution OCT technique has a potential for noninvasive, accurate, and continuous glucose monitoring with high sensitivity.

Concentration of the Most-Cited Papers in the Scientific Literature: Analysis of Journal Ecosystems

PubMed Central

Ioannidis, John P. A.

2006-01-01

Background A minority of scientific journals publishes the majority of scientific papers and receives the majority of citations. The extent of concentration of the most influential articles is less well known. Methods/Principal Findings The 100 most-cited papers in the last decade in each of 21 scientific fields were analyzed; fields were considered as ecosystems and their “species” (journal) diversity was evaluated. Only 9% of journals in Journal Citation Reports had published at least one such paper. Among this 9%, half of them had published only one such paper. The number of journals that had published a larger number of most-cited papers decreased exponentially according to a Lotka law. Except for three scientific fields, six journals accounted for 53 to 94 of the 100 most-cited papers in their field. With increasing average number of citations per paper (citation density) in a scientific field, concentration of the most-cited papers in a few journals became even more prominent (p<0.001). Concentration was unrelated to the number of papers published or number of journals available in a scientific field. Multidisciplinary journals accounted for 24% of all most-cited papers, with large variability across fields. The concentration of most-cited papers in multidisciplinary journals was most prominent in fields with high citation density (correlation coefficient 0.70, p<0.001). Multidisciplinary journals had published fewer than eight of the 100 most-cited papers in eight scientific fields (none in two fields). Journals concentrating most-cited original articles often differed from those concentrating most-cited reviews. The concentration of the most-influential papers was stronger than the already prominent concentration of papers published and citations received. Conclusions Despite a plethora of available journals, the most influential papers are extremely concentrated in few journals, especially in fields with high citation density. Existing multidisciplinary journals publish selectively most-cited papers from fields with high citation density. PMID:17183679

Efficient uranium capture by polysulfide/layered double hydroxide composites.

PubMed

Ma, Shulan; Huang, Lu; Ma, Lijiao; Shim, Yurina; Islam, Saiful M; Wang, Pengli; Zhao, Li-Dong; Wang, Shichao; Sun, Genban; Yang, Xiaojing; Kanatzidis, Mercouri G

2015-03-18

There is a need to develop highly selective and efficient materials for capturing uranium (normally as UO2(2+)) from nuclear waste and from seawater. We demonstrate the promising adsorption performance of S(x)-LDH composites (LDH is Mg/Al layered double hydroxide, [S(x)](2-) is polysulfide with x = 2, 4) for uranyl ions from a variety of aqueous solutions including seawater. We report high removal capacities (q(m) = 330 mg/g), large K(d)(U) values (10(4)-10(6) mL/g at 1-300 ppm U concentration), and high % removals (>95% at 1-100 ppm, or ∼80% for ppb level seawater) for UO2(2+) species. The S(x)-LDHs are exceptionally efficient for selectively and rapidly capturing UO2(2+) both at high (ppm) and trace (ppb) quantities from the U-containing water including seawater. The maximum adsorption coeffcient value K(d)(U) of 3.4 × 10(6) mL/g (using a V/m ratio of 1000 mL/g) observed is among the highest reported for U adsorbents. In the presence of very high concentrations of competitive ions such as Ca(2+)/Na(+), S(x)-LDH exhibits superior selectivity for UO2(2+), over previously reported sorbents. Under low U concentrations, (S4)(2-) coordinates to UO2(2+) forming anionic complexes retaining in the LDH gallery. At high U concentrations, (S4)(2-) binds to UO2(2+) to generate neutral UO2S4 salts outside the gallery, with NO3(-) entering the interlayer to form NO3-LDH. In the presence of high Cl(-) concentration, Cl(-) preferentially replaces [S4](2-) and intercalates into LDH. Detailed comparison of U removal efficiency of S(x)-LDH with various known sorbents is reported. The excellent uranium adsorption ability along with the environmentally safe, low-cost constituents points to the high potential of S(x)-LDH materials for selective uranium capture.

The Nutrient Pool of Five Important Bottomland Hardwood Soils

Treesearch

John K. Francis

1988-01-01

Heretofore, with the exception of N, the concentration of total nutrients and the amount of variation in nutrient concentrations among and within soil series and depths within the rooting zone of forested alluvial soils of the South was unknown. Information about total nutrient concentrations is important in studying the danger of nutrient depletion posed by total tree...

40 CFR 60.2690 - How do I conduct the initial and annual performance test?

Code of Federal Regulations, 2010 CFR

2010-07-01

... part must be used for gas composition analysis, including measurement of oxygen concentration. Method... concentrations, except for opacity, must be adjusted to 7 percent oxygen using Equation 1 of this section: Cadj = Cmeas (20.9−7)/(20.9−%O2)(Eq. 1) Where: Cadj = pollutant concentration adjusted to 7 percent oxygen...

Nutrient concentrations and their relations to the biotic integrity of wadeable streams in Wisconsin

USGS Publications Warehouse

Robertson, Dale M.; Graczyk, David J.; Garrison, Paul J.; Wang, Lizhu; LaLiberte, Gina; Bannerman, Roger

2006-01-01

Excessive nutrient (phosphorus and nitrogen) loss from watersheds is frequently associated with degraded water quality in streams. To reduce this loss, agricultural performance standards and regulations for croplands and livestock operations are being proposed by various States. In addition, the U.S. Environmental Protection Agency is establishing regionally based nutrient criteria that can be refined by each State to determine whether actions are needed to improve a stream's water quality. More confidence in the environmental benefits of the proposed performance standards and nutrient criteria will be possible with a better understanding of the biotic responses to a range of nutrient concentrations in different environmental settings. The U.S. Geological Survey and the Wisconsin Department of Natural Resources collected data from 240 wadeable streams throughout Wisconsin to: 1) describe how nutrient concentrations and biotic-community structure vary throughout the State; 2) determine which environmental characteristics are most strongly related to the distribution of nutrient concentrations; 3) determine reference water-quality and biotic conditions for different areas of the State; 4) determine how the biotic community of streams in different areas of the State respond to changes in nutrient concentrations; 5) determine the best regionalization scheme to describe the patterns in reference conditions and the responses in water quality and the biotic community; and 6) develop new indices to estimate nutrient concentrations in streams from a combination of biotic indices. The ultimate goal of this study is to provide the information needed to guide the development of regionally based nutrient criteria for Wisconsin streams. For total nitrogen (N) and suspended chlorophyll (SCHL) concentrations and water clarity, regional variability in reference conditions and in the responses in water quality to changes in land use are best described by subdividing wadeable streams into two categories: streams in areas with high clay-content soils (Environmental Phosphorus Zone 3, EPZ 3) and streams throughout the rest of the State. The regional variability in the response in total phosphorus (P) concentrations is also best described by subdividing the streams into these two categories; however, little consistent variability was found in reference P concentrations in streams throughout the State. Reference P concentrations are smilar throughout the State (0.03-0.04 mg/L). Reference N concentrations are divided into two categories: 0.6-0.7 mg/L in all streams except those in areas with high clay-content soils, where 0.4 mg/L is more appropriate. Reference SCHL concentrations are divided into two categories: 1.2-1.7 ?g/L in all streams except those in areas with high clay-content soils, where 1.0 ?g/L may be more appropriate. Reference water clarity is divided into two categories: streams in areas with high clay-content soils with a lower reference water clarity (Secchi tube depth, SD, of about 110 cm) and streams throughout the rest of the State (SD greater than or equal to about 115 cm). For each category of the biotic community (SCHL and benthic chlorophyll a concentrations (BCHL), periphytic diatoms, macroinvertebrates, and fish), a few biotic indices were more related to differences in nutrient concentrations than were others. For each of the indices more strongly related to nutrient concentrations, reference conditions were obtained by determining values corresponding to the worst 75th percentile value from a subset of minimally impacted streams (streams having reference nutrient concentrations). By examining the biotic community in streams having either reference P or N concentrations but not both, the relative importance of these two nutrients was determined. For SCHL, P was the more important limiting nutrient; however, for BCHL and all macroinvertebrate indices, it appears that N was the more important nutrient when concent

Molybdenum Availability Is Key to Nitrate Removal in Contaminated Groundwater Environments

PubMed Central

Thorgersen, Michael P.; Lancaster, W. Andrew; Vaccaro, Brian J.; Poole, Farris L.; Rocha, Andrea M.; Mehlhorn, Tonia; Pettenato, Angelica; Ray, Jayashree; Waters, R. Jordan; Melnyk, Ryan A.; Chakraborty, Romy; Deutschbauer, Adam M.; Arkin, Adam P.

2015-01-01

The concentrations of molybdenum (Mo) and 25 other metals were measured in groundwater samples from 80 wells on the Oak Ridge Reservation (ORR) (Oak Ridge, TN), many of which are contaminated with nitrate, as well as uranium and various other metals. The concentrations of nitrate and uranium were in the ranges of 0.1 μM to 230 mM and <0.2 nM to 580 μM, respectively. Almost all metals examined had significantly greater median concentrations in a subset of wells that were highly contaminated with uranium (≥126 nM). They included cadmium, manganese, and cobalt, which were 1,300- to 2,700-fold higher. A notable exception, however, was Mo, which had a lower median concentration in the uranium-contaminated wells. This is significant, because Mo is essential in the dissimilatory nitrate reduction branch of the global nitrogen cycle. It is required at the catalytic site of nitrate reductase, the enzyme that reduces nitrate to nitrite. Moreover, more than 85% of the groundwater samples contained less than 10 nM Mo, whereas concentrations of 10 to 100 nM Mo were required for efficient growth by nitrate reduction for two Pseudomonas strains isolated from ORR wells and by a model denitrifier, Pseudomonas stutzeri RCH2. Higher concentrations of Mo tended to inhibit the growth of these strains due to the accumulation of toxic concentrations of nitrite, and this effect was exacerbated at high nitrate concentrations. The relevance of these results to a Mo-based nitrate removal strategy and the potential community-driving role that Mo plays in contaminated environments are discussed. PMID:25979890

Evaluation of trace element status of organic dairy cattle.

PubMed

Orjales, I; Herrero-Latorre, C; Miranda, M; Rey-Crespo, F; Rodríguez-Bermúdez, R; López-Alonso, M

2018-06-01

The present study aimed to evaluate trace mineral status of organic dairy herds in northern Spain and the sources of minerals in different types of feed. Blood samples from organic and conventional dairy cattle and feed samples from the respective farms were analysed by inductively coupled plasma mass spectrometry to determine the concentrations of the essential trace elements (cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), iodine (I), manganese (Mn), molybdenum (Mo), nickel (Ni), selenium (Se) and zinc (Zn)) and toxic trace elements (arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb)). Overall, no differences between organic and conventional farms were detected in serum concentrations of essential and toxic trace elements (except for higher concentrations of Cd on the organic farms), although a high level of inter-farm variation was detected in the organic systems, indicating that organic production greatly depends on the specific local conditions. The dietary concentrations of the essential trace elements I, Cu, Se and Zn were significantly higher in the conventional than in the organic systems, which can be attributed to the high concentration of these minerals in the concentrate feed. No differences in the concentrations of trace minerals were found in the other types of feed. Multivariate chemometric analysis was conducted to determine the contribution of different feed sources to the trace element status of the cattle. Concentrate samples were mainly associated with Co, Cu, I, Se and Zn (i.e. with the elements supplemented in this type of feed). However, pasture and grass silage were associated with soil-derived elements (As, Cr, Fe and Pb) which cattle may thus ingest during grazing.

Season and light affect constitutive defenses of understory shrub species against folivorous insects

NASA Astrophysics Data System (ADS)

Karolewski, Piotr; Giertych, Marian J.; Żmuda, Michał; Jagodziński, Andrzej M.; Oleksyn, Jacek

2013-11-01

Understory shrubs contribute to overall species diversity, providing habitat and forage for animals, influence soil chemistry and forest microclimate. However, very little is known about the chemical defense of various shrub species against folivorous insects. Using six shrub species, we tested how seasonal changes and light conditions affect their constitutive defense to insect damage. We monitored leaf perforation, concentrations of total phenols, condensed tannins, nitrogen (N), and total nonstructural carbohydrates (TNC). Leaf damage caused by insects was low in Sambucus nigra, Cornus sanguinea, and Frangula alnus, intermediate in Corylus avellana and Prunus serotina, and high in Prunus padus. Leaves of all the species, when growing in high light conditions, had high concentrations of defense metabolites. Except for C. avellana, leaves of the other shrub species growing in full sun were less injured than those in shade. This may be due to higher concentrations of defense metabolites and lower concentrations of nitrogen. Similar patterns of the effects of light on metabolites studied and N were observed for leaves with varying location within the crown of individual shrubs (from the top of the south direction to the bottom of the north), as for leaves from shrubs growing in full sun and shrubs in the shade of canopy trees. A probable cause of the greater damage of more sunlit leaves of C. avellana was the fact that they were herbivorized mostly by Altica brevicollis, a specialist insect that prefers plant tissues with a high TNC level and is not very sensitive to a high level of phenolic compounds.

Phosphorus reduces the zinc concentration in cereals pot-grown on calcareous Vertisols from southern Spain.

PubMed

Sánchez-Rodríguez, Antonio Rafael; Del Campillo, María Carmen; Torrent, José

2017-08-01

Zinc deficiency, a major problem in crops grown on soils low in available Zn, is even more important in phosphorus-rich soils. This work aimed to elucidate the effects of soil P and Zn levels, and of fertilizer application, on yield and Zn concentration in cereal grains. Wheat and barley were successively pot-grown on 20 calcareous Vertisols low in available Zn and ranging widely in available P. Grain yield in the plants grown on the native soils was positively correlated with Olsen P but not with diethylenetriaminepentaacetic acid (DTPA)-extractable Zn except for wheat on P-rich soils. Grain Zn concentration was negatively correlated with Olsen P. Grain Zn uptake differed little among soils. Application of P to the soils increased grain yield insignificantly and P concentration significantly; however, it reduced grain Zn concentration (particularly at low Olsen P values). Applying Zn alone only increased grain Zn concentration, whereas applying P and Zn in combination increased yield and grain Zn concentration at low and high Olsen P values, respectively. Applying P alone to plants grown on calcareous Vertisols low in available P and Zn may in practice reduce grain Zn concentrations while not increasing grain yield significantly. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Geochemistry and mineralogy of fly-ash from the Mae Moh lignite deposit, Thailand

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

Hart, B.R.; Powell, M.A.; Fyfe, W.S.

The concentration of 21 elements in fly ash from three boilers (75 MW, 150 MW, and 300 MW) at the EGAT power plant, Mae Moh, Thailand, were determined by INAA. The concentration of 10 major elements was determined by XRF. As, Co, Cr, Ni, Mo, and Sb generally increase in concentration going from bottom ash (BA) through the sequence of electrostatic precipitator ashes (ESPA) and reach maxima of As (352 ppm), Co (45 ppm), Cr (105 ppm), Mo (32 ppm), Ni (106 ppm), and Sb (15 ppm) in the ESPA. Ce, Cs, Fe, Hf, La, Sc, Ta, Tb, and Ybmore » did not exhibit concentration trends or are variable except in the case of one boiler, which showed an increase going from BA to ESPA. Only Br decreased in composition going from BA to ESPA. Rb, Sm, U, and Th showed marked variation in trends. The major elements identified by EDS were Al, Si, S, K, Ca, Fe, and Ba, with minor amounts of Mg, Na, Ti, Mn, and Sr. Al, Si, K, and Ca occur together and are present in most of the fly-ash particles. Ba was found as a major component with Ca, Al, and Si. Fe and Ca are usually associated with sulfur. Some small spheres (< 5 {mu}m) are comprised almost entirely of Fe (probably as oxide). Symplectite textures are noted in high-Fe phases. All elements except Br are significantly enriched in the fly ash relative to the coal, which contains 35% ash. Particle chemistry is consistent with the major mineral phases identified by XRD, which include: quartz, magnetite, mullite, gehlenite, anorthite, hematite, anhydrite, and clinopyroxene.« less

Characteristics of dissolved organic matter formed in aerobic and anaerobic digestion of excess activated sludge.

PubMed

Du, Haixia; Li, Fusheng

2017-02-01

The characteristics of dissolved organic matter (DOM) formed in aerobic and anaerobic digestion of excess activated sludge (EAS) was investigated for three total solid (TS) concentrations (1.2, 2.3 and 5.2%) and three temperatures (5, 20 and 35 °C). The results on the overall concentration of DOM evaluated by TOC showed significantly higher values in anaerobic than aerobic digestion (2.8-6.9 times for TS 1.2-5.2% at 20 °C). Data analysis with a first-order sequential reaction model revealed that higher occurrence of DOM in anaerobic digestion was a result of comparatively faster hydrolysis (1.3-5.5 times for TS 1.2-5.2% at 20 °C; 1.4-49.3 times for temperatures 5-35 °C with TS 1.2%) and slower degradation (0.3-1.0 times for TS 1.2-5.2% at 20 °C; 0.5-8.3 times for temperatures 5-35 °C with TS 1.2%). In aerobic digestion, more humic substances were formed; while, in anaerobic digestion, proteins and aromatic amino acids were the major constituents. For both digestions, except for a few exceptions, proteins and humic substances increased as the TS concentration increased; and increasing the temperature led to a decrease in the content of proteins formed in both aerobic and anaerobic digestion, and an increase in the content of humic substances in the aerobic digestion. The UV-absorbing DOM constituents were highly heterogeneous, and were comparatively larger in anaerobic digestion; and did not change significantly with the TS concentrations and temperatures. Copyright © 2016 Elsevier Ltd. All rights reserved.

Chemistry and long-term decomposition of roots of Douglas-fir grown under elevated atmospheric carbon dioxide and warming conditions.

PubMed

Chen, H; Rygiewicz, P T; Johnson, M G; Harmon, M E; Tian, H; Tang, J W

2008-01-01

Elevated atmospheric CO(2) concentrations and warming may affect the quality of litters of forest plants and their subsequent decomposition in ecosystems, thereby potentially affecting the global carbon cycle. However, few data on root tissues are available to test this feedback to the atmosphere. In this study, we used fine (diameter < or = 2 mm) and small (2-10 mm) roots of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings that were grown for 4 yr in a 2 x 2 factorial experiment: ambient or elevated (+ 180 ppm) atmospheric CO(2) concentrations, and ambient or elevated (+3.8 degrees C) atmospheric temperature. Exposure to elevated CO(2) significantly increased water-soluble extractives concentration (%WSE), but had little effect on the concentration of N, cellulose, and lignin of roots. Elevated temperature had no effect on substrate quality except for increasing %WSE and decreasing the %lignin content of fine roots. No significant interaction was found between CO(2) and temperature treatments on substrate quality, except for %WSE of the fine roots. Short-term (< or = 9 mo) root decomposition in the field indicated that the roots from the ambient CO(2) and ambient temperature treatment had the slowest rate. However, over a longer period of incubation (9-36 mo) the influence of initial substrate quality on root decomposition diminished. Instead, the location of the field incubation sites exhibited significant control on decomposition. Roots at the warmer, low elevation site decomposed significantly faster than the ones at the cooler, high elevation site. This study indicates that short-term decomposition and long-term responses are not similar. It also suggests that increasing atmospheric CO(2) had little effect on the carbon storage of Douglas-fir old-growth forests of the Pacific Northwest.

Plasma amino acid profiles in healthy East Asian subpopulations living in Japan.

PubMed

Nakamura, Hidehiro; Nishikata, Natsumi; Kawai, Nobuhiro; Imaizumi, Akira; Miyano, Hiroshi; Mori, Maiko; Yamamoto, Hiroshi; Noguchi, Yasushi

2016-01-01

Profiles of plasma free amino acids (PFAAs) have been utilized as biomarkers to detect various diseases. However, few studies have investigated whether ethnicity or specific subpopulations within East Asia influence PFAA concentrations. A total of 95 healthy volunteers living in Japan, including 31 Japanese individuals, 36 Korean individuals and 28 Chinese individuals, were enrolled. Participants' PFAA levels were measured by high-performance liquid chromatography mass spectrometry, and the effects of factors such as sex, age, body mass index (BMI) and subpopulation on PFAA profiles were analyzed. With the exception of glutamine and α-aminobutyric acid, there were no significant differences among the three examined subpopulations with respect to either the means or the distributions of PFAA concentrations. A multiple regression analysis revealed that most of the PFAA concentrations were significantly related to sex. Ornithine concentrations, glutamate concentrations, and glutamine and α-aminobutyric acid concentrations were significantly associated with age, BMI, and Chinese subpopulation, respectively. The study results indicate that the contributions of subpopulation within East Asia to PFAA profiles are small, particularly relative to the contributions provided by sex. © 2015 The Authors American Journal of Human Biology Published by Wiley Periodicals, Inc.

Phytotoxicity evaluation of some commonly used shampoos using Brassica napus L.

PubMed

Naeem, Faiqa; Ahmed, Faiza; Kanwal, Memoona; Murad, Waheed; Azizullah, Azizullah

2015-10-01

Hair shampoos are among the most commonly used chemicals in everyday life. Since shampoos are a major component of domestic and municipal wastewater, they may affect plants when irrigated with wastewater. However, their effects on plants have never been investigated in detail. The present study was aimed to evaluate the effect of some commonly used hair shampoos on seed germination and seedling vigor of Brassica napus. Seeds of Brassica napus were exposed to different concentrations of hair shampoos, i.e., 0 (control), 0.001, 0.01, 0.1, 1.0, and 10 %. The obtained results revealed that germination was not very sensitive to shampoo stress and was significantly inhibited only at the highest tested concentration (10 %) of shampoo except in the case of one shampoo where it was inhibited at concentration of 1 % or above. The other tested parameters of Brassica napus were comparatively more sensitive than germination to shampoo stress. However, at lower concentrations of shampoos, stimulatory effects were also observed in some cases. Although no exact data is available on shampoo concentration in wastewater used for irrigation, it is unlikely that shampoo concentration in irrigation water reach so high and pose adversity to plants.

Photoluminescence properties of polystyrene-hosted fluorophore thin films

NASA Astrophysics Data System (ADS)

Chakraborty, Subha; Harris, Katherine; Huang, Mengbing

2016-12-01

We report on a photo-luminescence study of four different fluorophores: Coumarin 6, 2,5-Diphenyloxazole (PPO), 1,4-Bis(5-phenyl-2-oxazolyl)benzene (POPOP) and Para-terpehnyl (PTP), doped in a polystyrene-based thin film. All of the samples are prepared by spin coating from a non-polar polymer solution at various concentrations. Their emission spectra and transient properties are characterized by photoluminescence measurements. Red-shifts in the emission spectra are observed for all four types of fluorophores as their concentration increases. We explain this phenomenon based on concentration dependence of solvatochromic effects and the results show good agreement with existing literature. We also show that the singlet-singlet annihilation processes are possibly a prevalent mechanism in the high concentration regime that affects the steady state and transient emission characteristics of the fluors. With the exception of PTP, photoluminescence quenching occurs as the fluorophore concentration in the polymer is increased. Rate equations for excited state decay mechanisms are analysed by considering different radiative and non-radiative energy transfer mechanisms. The results show consistency with our experimental observations. PTP shows the best photoluminescence results as an efficient fluor in the thin film, whereas PPO shows the strongest concentration dependent quenching and an anomalous lifetime distribution.

PBDEs, PBBs, and PCNs in three communities of free-ranging killer whales (Orcinus orca) from the northeastern Pacific Ocean.

PubMed

Rayne, Sierra; Ikonomou, Michael G; Ross, Peter S; Ellis, Graeme M; Barrett-Lennard, Lance G

2004-08-15

Polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), and polychlorinated naphthalenes (PCNs) were quantified in blubber biopsy samples collected from free-ranging male and female killer whales (Orcinus orca) belonging to three distinct communities (southern residents, northern residents, and transients) from the northeastern Pacific Ocean. High concentrations of sigmaPBDE were observed in male southern residents (942+/-582 ng/g Iw), male and female transients (1015+/-605 and 885+/-706 ng/g Iw, respectively), and male and female northern residents (203+/-116 and 415+/-676 ng/g Iw, respectively). Because of large variation within sample groups, sigmaPBDE levels generally did not differ statistically with the exception of male northern residents, which had lower sigmaPBDE concentrations than male southern residents, male transients, and female transients, perhaps reflecting the consumption of less contaminated prey items. Male transient killer whales, which consume high trophic level prey including other cetaceans and occasionally spend time near populated areas, had sigmaPBDE concentrations approximately equal to southern residents. No significant age-related relationships were observed for sigmaPBDE concentrations. sigmaPBDE concentrations were approximately 1-3 orders of magnitude greater than those of sigmaPBB (3.0-31 ng/g Iw) and sigmaPCN (20-167 ng/g Iw) measured in a subset of samples, suggesting that PBDEs may represent a contaminant class of concern in these marine mammals.

Determination of mycotoxins in different food commodities by ultra-high-pressure liquid chromatography coupled to triple quadrupole mass spectrometry.

PubMed

Beltrán, Eduardo; Ibáñez, María; Sancho, Juan Vicente; Hernández, Félix

2009-06-01

A rapid multianalyte-multiclass method with little sample manipulation has been developed for the simultaneous determination of eleven mycotoxins in different food commodities by using ultra-high-pressure liquid chromatography coupled to triple quadrupole mass spectrometry (UHPLC/MS/MS). Toxins were extracted from the samples with acetonitrile/water (80:20, v/v) 0.1% HCOOH and, after a two-fold dilution with water, directly injected into the system. Thanks to the fast high-resolution separation of UHPLC, the eleven mycotoxins were separated by gradient elution in only 4 min. The method has been validated in three food matrices (maize kernels, dry pasta (wheat), and eight-multicereal babyfood (wheat, maize, rice, oat, barley, rye, sorghum, millet)) at four different concentration levels. Satisfactory recoveries were obtained (70-110%) and precision (expressed as relative standard deviation) was typically below 15% with very few exceptions. Quantification of samples was carried out with matrix-matched standards calibration. The lowest concentration successfully validated in sample was as low as 0.5 microg/kg for aflatoxins and ochratoxin A in babyfood, and 20 microg/kg for the rest of the selected mycotoxins in all matrices tested. Deoxynivalenol could be only validated at 200 microg/kg, due the poor sensitivity for this mycotoxin analysis. With only two exceptions (HT-2 and deoxynivalenol), the limits of detection (LODs), estimated for a signal-to-noise ratio of 3 from the chromatograms of samples spiked at the lowest level validated, varied between 0.1 and 1 microg/kg in the three food matrices tested. The method was applied to the analysis of different kinds of samples. Positive findings were confirmed by acquiring two transitions (Q quantification, q confirmation) and evaluating the Q/q ratio. Copyright (c) 2009 John Wiley & Sons, Ltd.

Chemical composition and nutritional potential of yam bean seeds (Pachyrhizus erosus L. urban).

PubMed

Santos, A C; Cavalcanti, M S; Coelho, L C

1996-01-01

Pachyrhizus erosus seeds were analysed for proximate composition, minerals, protein fractions, antinutritional factors, and rotenoids. The seeds showed a high content of proteins, lipids, Fe and Ca, in comparison to other legumes. Glutelins constitute the highest protein fraction, followed by globulins. Antinutritional substances detected as tannins, hemagglutinating activity and trypsin inhibitory activity, were in low concentrations. Seeds were also processed to obtain a flour which showed proper characteristics, good in vitro digestibility, significant rotenoid reduction level and amino acid composition rich in essential amino acids, except methionine.

Evidence of latitudinal fractionation of polychlorinated biphenyl congeners along the Baltic Sea region

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

Agrell, C.; Okla, L.; Larsson, P.

Annual cycles of the atmospheric concentrations of PCBs were determined at 16 (mostly rural) stations around the Baltic Sea between 1990 and 1993. The concentration levels of individual congeners were found to be influenced by their physical-chemical properties, ambient temperature, and geographical location. Median levels of PCBs were similar at all stations except at one urban site near Riga. A latitudinal gradient with higher levels in the south was found for the sum of PCB as well as for individual congeners, and the gradient was more pronounced for the low volatility congeners. As a result, the high volatility congeners increasedmore » in relative importance with latitude. Generally, PCB concentrations increased with temperature, but slopes of the partial pressure in air versus reciprocal temperature were different between congeners and between stations. In general, the low volatility congeners were more temperature dependent than the high volatility PCB congeners. Steep slopes at a sampling location indicate that the concentration in air is largely determined by diffusive exchange with soils. Lack of a temperature dependence may be due to the influence of long-range transported air masses at remote sites and due to the episodic or random nature of PCB sources at urban sites.« less

Patchiness of phytoplankton and primary production in Liaodong Bay, China.

PubMed

Pei, Shaofeng; Laws, Edward A; Zhang, Haibo; Ye, Siyuan; Yuan, Hongming; Liu, Haiyue

2017-01-01

A comprehensive study of water quality, phytoplankton biomass, and photosynthetic rates in Liaodong Bay, China, during June and July of 2013 revealed two large patches of high biomass and production with dimensions on the order of 10 km. Nutrient concentrations were above growth-rate-saturating concentrations throughout the bay, with the possible exception of phosphate at some stations. The presence of the patches therefore appeared to reflect the distribution of water temperature and variation of light penetration restricted by water turbidity. There was no patch of high phytoplankton biomass or production in a third, linear patch of water with characteristics suitable for rapid phytoplankton growth; the absence of a bloom in that patch likely reflected the fact that the width of the patch was less than the critical size required to overcome losses of phytoplankton to turbulent diffusion. The bottom waters of virtually all of the eastern half of the bay were below the depth of the mixed layer, and the lowest bottom water oxygen concentrations, 3-5 mg L-1, were found in that part of the bay. The water column in much of the remainder of the bay was within the mixed layer, and oxygen concentrations in both surface and bottom waters exceeded 5 mg L-1.

Patchiness of phytoplankton and primary production in Liaodong Bay, China

PubMed Central

Laws, Edward A.; Zhang, Haibo; Ye, Siyuan; Yuan, Hongming; Liu, Haiyue

2017-01-01

A comprehensive study of water quality, phytoplankton biomass, and photosynthetic rates in Liaodong Bay, China, during June and July of 2013 revealed two large patches of high biomass and production with dimensions on the order of 10 km. Nutrient concentrations were above growth-rate-saturating concentrations throughout the bay, with the possible exception of phosphate at some stations. The presence of the patches therefore appeared to reflect the distribution of water temperature and variation of light penetration restricted by water turbidity. There was no patch of high phytoplankton biomass or production in a third, linear patch of water with characteristics suitable for rapid phytoplankton growth; the absence of a bloom in that patch likely reflected the fact that the width of the patch was less than the critical size required to overcome losses of phytoplankton to turbulent diffusion. The bottom waters of virtually all of the eastern half of the bay were below the depth of the mixed layer, and the lowest bottom water oxygen concentrations, 3–5 mg L–1, were found in that part of the bay. The water column in much of the remainder of the bay was within the mixed layer, and oxygen concentrations in both surface and bottom waters exceeded 5 mg L–1. PMID:28235070

Reduction of Hexavalent Chromium and Detection of Chromate Reductase (ChrR) in Stenotrophomonas maltophilia.

PubMed

Baldiris, Rosa; Acosta-Tapia, Natali; Montes, Alfredo; Hernández, Jennifer; Vivas-Reyes, Ricardo

2018-02-13

An Gram negative strain of S. maltophilia , indigenous to environments contaminated by Cr(VI) and identified by biochemical methods and 16S rRNA gene analysis, reduced chromate by 100%, 98-99% and 92% at concentrations in the 10-70, 80-300, and 500 mg/L range, respectively at pH 7 and temperature 37 °C. Increasing concentrations of Cr(VI) in the medium lowered the growth rate but could not be directly correlated with the amount of Cr(VI) reduced. The strain also exhibited multiple resistance to antibiotics and tolerance and resistance to various heavy metals (Ni, Zn and Cu), with the exception of Hg. Hexavalent chromium reduction was mainly associated with the soluble fraction of the cell evaluated with crude cell-free extracts. A protein of molecular weight around 25 kDa was detected on SDS-PAGE gel depending on the concentration of hexavalent chromium in the medium (0, 100 and 500 mg/L). In silico analysis in this contribution, revealed the presence of the chromate reductase gene ChrR in S. maltophilia , evidenced through a fragment of around 468 bp obtained experimentally. High Cr(VI) concentration resistance and high Cr(VI) reducing ability of the strain make it a suitable candidate for bioremediation.

Short-Term Effects of Low-Level Heavy Metal Contamination on Soil Health Analyzed by Nematode Community Structure.

PubMed

Park, Byeong-Yong; Lee, Jae-Kook; Ro, Hee-Myong; Kim, Young Ho

2016-08-01

The short-term effects of low-level contamination by heavy metals (As, Cd, Cu, and Pb) on the soil health were examined by analyzing soil nematode community in soils planted with tomatoes. For this, the soils were irrigated with five metal concentrations ([1, 1/4, 1/4(2), 1/4(3), and 0] × maximum concentrations [MC] detected in irrigation waters near abandoned mine sites) for 18 weeks. Heavy metal concentrations were significantly increased in soils irrigated with MC of heavy metals, among which As and Cu exceeded the maximum heavy metal residue contents of soil approved in Korea. In no heavy metal treatment controls, nematode abundances for all trophic groups (except omnivorous-predatory nematodes [OP]) and colonizer-persister (cp) values (except cp-4-5) were significantly increased, and all maturity indices (except maturity index [MI] of plant-parasitic nematodes) and structure index (SI) were significantly decreased, suggesting the soil environments might have been disturbed during 18 weeks of tomato growth. There were no concentration-dependent significant decreases in richness, abundance, or MI for most heavy metals; however, their significant decreases occurred in abundance and richness of OP and cp-4, MI2-5 (excluding cp-1) and SI, indicating disturbed soil ecosystems, at the higher concentrations (MC and MC/4) of Pb that had the most significant negative correlation coefficients for heavy metal concentrations and nematode community among the heavy metals. Therefore, the short-term effects of low-level heavy metal contamination on soil health can be analyzed by nematode community structures before the appearance of plant damages caused by the abiotic agents, heavy metals.

Distribution and biogeochemical controls on net methylmercury production in Penobscot River marshes and sediment.

PubMed

Gilmour, Cynthia; Bell, James Tyler; Soren, Ally Bullock; Riedel, Georgia; Riedel, Gerhardt; Kopec, A Dianne; Bodaly, R A

2018-06-01

The distribution of mercury and methylmercury (MeHg) in sediment, mudflats, and marsh soils of the Hg-contaminated tidal Penobscot River was investigated, along with biogeochemical controls on production. Average total Hg in surface samples (0-3 cm) ranged from 100 to 1200 ng/g; average MeHg ranged from 5 to 50 ng/g. MeHg was usually highest at or near the surface except in highly mobile mudflats. Although total Hg concentrations in the Penobscot are elevated, it is the accumulation of MeHg that stands out in comparison to other ecosystems. Surface soils in the large Mendall Marsh, about 17 km downstream from the contamination source, contained particularly high %MeHg (averaging 8%). In Mendall marsh soil porewaters, MeHg often accounted for more than half of total Hg. Salt marshes are areas of particular concern in the Penobscot River, for they are depositional environments for a Hg-contaminated mobile pool of river sediment, hot spots for net MeHg production, and sources of risk to marsh animals. We hypothesized that exceptionally low mercury partitioning between the solid and aqueous phases (with log K d averaging ~4.5) drives high MeHg in Penobscot marshes. The co-occurrence of iron and sulfide in filtered soil porewaters, sometimes both above 100 μM, suggests the presence of nanoparticulate and/or colloidal metal sulfides. These colloids may be stabilized by high concentrations of aromatic and potentially sulfurized dissolved organic matter (DOM) in marsh soils. Thus, Hg in Penobscot marsh soils appears to be in a highly available for microbial methylation through the formation of DOM-associated HgS complexes. Additionally, low partitioning of MeHg to marsh soils suggests high MeHg bioavailability to animals. Overall, drivers of high MeHg in Penobscot marshes include elevated Hg in soils, low partitioning of Hg to solids, high Hg bioavailability for methylation, rapidly shifting redox conditions in surface marsh soils, and high rates of microbial activity. Copyright © 2018 Elsevier B.V. All rights reserved.

Size heterogeneity of epidermal growth factor in human body fluids

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

Pesonen, K.; Viinikka, L.; Koskimies, A.

The authors measured the concentration of immunoreactive (IR) hEGF in various body fluids by radioimmunoassay (RIA) and evaluated its size heterogeneity by size exclusion high performance liquid chromatography combined with RIA or with time-resolved immunofluorometric assay (TR-IFMA). Mean concentration was 80 ng/ml in urine, 65 ng/ml in milk, 50 ng/ml in seminal plasma, 25 ng/ml in armpit sweat, 1 ng/ml in breast sweat, 0.3 ng/ml in third-trimester amniotic fluid, 3 ng/ml in saliva, 1.5 ng/ml in tears and 0.3 ng/ml in gastric juice. All the fluids except armpit sweat and gastric juice contained two to five molecular sizes of IR-hEGF.more » As well as the 6200-dalton (6.2kDa) hEGF the authors found at least four other different molecular sizes with approximate weights of greater than or equal to300, 150, 70 and 20 kDa. The authentic 6.2kDa form made up >90% of the total IR-hEGF in all except the amniotic fluid where its proportion was 71%, and the seminal plasma where the proportion could not be determined. 18 references, 1 figure, 1 table.« less

Water-quality, sediment-quality, stream-habitat, and biological data for Mustang Bayou near Houston, Texas, 2004-05

USGS Publications Warehouse

Sneck-Fahrer, Debra A.; East, Jeffery W.

2007-01-01

The U.S. Geological Survey, in cooperation with the Houston-Galveston Area Council and the Texas Commission on Environmental Quality, collected water-quality, stream-habitat, and biological data from six sites (downstream order M6-M1) primarily in Brazoria County southeast of Houston, Texas, during September 2004-August 2005 and collected bed sediment data from one site in September 2005. Water-quality data collection consisted of continuously monitored (for periods of 24 hours to several days, six times) water temperature, pH, specific conductance, and dissolved oxygen and periodically collected samples of several properties and constituents. Monitored dissolved oxygen measurements were below minimum and 24-hour criteria at all sites except M2. Nitrogen compounds, phosphorus, biochemical oxygen demand, chlorophyll-a, E. coli, chloride, sulfate, solids, suspended sediment concentration, and pesticides were assessed at all sites. Concentrations of nitrogen compounds and phosphorus did not exceed Texas State screening levels. Biochemical oxygen demand was less than 4.0 milligrams per liter at all sites except M6, where the maximum concentration was 8.1 milligrams per liter. Concentrations of chlorophyll-a were less than the State screening level at all sites except M6, where four of eight samples equaled or exceeded the screening level. Twenty of 48 samples from Mustang Bayou had E. coli densities that exceeded the State single-sample water-quality standard. Median chloride concentrations from each site were between 42.2 and 123 milligrams per liter. Fifteen pesticide compounds (six herbicides and nine insecticides) were detected in 24 water samples. The most frequently detected pesticide was atrazine, which was found in every sample. Other frequently detected pesticides were 2-chloro-4-isopropylamino-6-amino-s-triazine (CIAT), prometon, tebuthiuron, fipronil, and the pesticide degradates, fipronil sulfide and fipronil sulfone. Sediment samples were collected from the stream bottom at M1 and analyzed for concentrations of trace elements (metals), polycyclic aromatic hydrocarbons, organochlorine pesticides, and polychlorinated biphenyls. No organochlorine pesticides or polychlorinated biphenyls were detected. No concentrations of metals exceeded State screening levels. Measurable concentrations of 11 polycyclic aromatic hydrocarbon (PAH) compounds were detected, and three other PAH compounds were detected but not quantified by the laboratory. Stream habitat and aquatic biota (benthic macroinvertebrates and fish) were surveyed at each site three times during the study to evaluate aquatic life use. Characteristics of habitat measured during each survey were scored using a habitat quality index. Average aquatic-life-use scores were 'limited' for M3-M6 and 'intermediate' for M1 and M2. A total of 2,557 macroinvertebrate individuals were identified from Mustang Bayou. Benthic macroinvertebrate assemblages were scored using indexes specified by the Texas Commission on Environmental Quality. Average aquatic-life-use scores were 'limited' at M1, 'intermediate' at M3-M6, and 'high' at M2. Forty-six species of fish representing 20 families were collected from Mustang Bayou. A total of 4,115 fish were collected. Sunfish (Centrarchidae) was the most abundant family, accounting for about 28 percent. Aquatic-life-use scores at sites in Mustang Bayou were determined using the regional index of biotic integrity for ecoregion 34 and were 'high' for all sites.

Distribution of emamectin benzoate in Atlantic salmon (Salmo salar L.).

PubMed

Sevatdal, S; Magnusson, A; Ingebrigtsen, K; Haldorsen, R; Horsberg, T E

2005-02-01

The aims of this study were to investigate the content of emamectin in blood, mucus and muscle following field administration of the recommended dose, and correlation with sea lice infection on the same fish (elimination study). The tissue distribution of tritiated emamectin benzoate after a single oral dose in Atlantic salmon was also investigated by means of whole-body autoradiography and scintillation counting (distribution study). In the elimination study, concentrations of emamectin benzoate reached maximum levels of 128, 105 and 68 ng/g (p.p.b.) for blood, mucus and muscle respectively, on day 7, the last day of administration. From day 7, the concentration in the blood declined until concentration was less than the limit of detection on day 77. The concentration was higher in mucus compared with plasma (P < 0.05) except on days 7 and 21. The concentration of emamectin benzoate decreased gradually from the end of treatment (day 7) to day 70 with half-lives of 9.2, 10.0 and 11.3 days in muscle, plasma and mucus respectively. The distribution study demonstrated a high quantity of radioactivity in mucous membranes (gastrointestinal tract, gills) throughout the observation period (56 days). Activity was high in the epiphysis, hypophysis and olfactory rosette throughout the study. The highest activity was observed in the bile, indicating this to be an important route for excretion. The distribution study confirmed the results from the elimination study with respect to concentrations in blood, skin mucous and muscle.

Variation of microorganism concentrations in urban stormwater runoff with land use and seasons.

PubMed

Selvakumar, Ariamalar; Borst, Michael

2006-03-01

Stormwater runoff samples were collected from outfalls draining small municipal separate storm sewer systems. The samples were collected from three different land use areas based on local designation (high-density residential, low-density residential and landscaped commercial). The concentrations of microorganisms in the stormwater runoff were found to be similar in magnitude to, but less variable than, those reported in the stormwater National Pollutant Discharge Elimination System (NPDES) database. Microorganism concentrations from high-density residential areas were higher than those associated with low-density residential and landscaped commercial areas. Since the outfalls were free of sanitary wastewater cross-connections, the major sources of microorganisms to the stormwater runoff were most likely from the feces of domestic animals and wildlife. Concentrations of microorganisms were significantly affected by the season during which the samples were collected. The lowest concentrations were observed during winter except for Staphylococcus aureus. The Pearson correlation coefficients among different indicators showed weak linear relationships and the relationships were statistically significant. However, the relationships between indicators and pathogens were poorly correlated and were not statistically significant, suggesting the use of indicators as evidence of the presence of pathogens is not appropriate. Further, the correlation between the concentration of the traditionally monitored indicators (total coliforms and fecal coliforms) and the suggested substitutes (enterococci and E. coli) is weak, but statistically significant, suggesting that historical time series will be only a qualitative indicator of impaired waters under the revised criteria for recreational water quality by the US EPA.

Spatial analysis and health risk assessment of heavy metals concentration in drinking water resources.

PubMed

Fallahzadeh, Reza Ali; Ghaneian, Mohammad Taghi; Miri, Mohammad; Dashti, Mohamad Mehdi

2017-11-01

The heavy metals available in drinking water can be considered as a threat to human health. Oncogenic risk of such metals is proven in several studies. Present study aimed to investigate concentration of the heavy metals including As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn in 39 water supply wells and 5 water reservoirs within the cities Ardakan, Meibod, Abarkouh, Bafgh, and Bahabad. The spatial distribution of the concentration was carried out by the software ArcGIS. Such simulations as non-carcinogenic hazard and lifetime cancer risk were conducted for lead and nickel using Monte Carlo technique. The sensitivity analysis was carried out to find the most important and effective parameters on risk assessment. The results indicated that concentration of all metals in 39 wells (except iron in 3 cases) reached the levels mentioned in EPA, World Health Organization, and Pollution Control Department standards. Based on the spatial distribution results at all studied regions, the highest concentrations of metals were derived, respectively, for iron and zinc. Calculated HQ values for non-carcinogenic hazard indicated a reasonable risk. Average lifetime cancer risks for the lead in Ardakan and nickel in Meibod and Bahabad were shown to be 1.09 × 10 -3 , 1.67 × 10 -1 , and 2 × 10 -1 , respectively, demonstrating high carcinogenic risk compared to similar standards and studies. The sensitivity analysis suggests high impact of concentration and BW in carcinogenic risk.

[Morphine-antiemetics mixtures for continuous subcutaneous infusion in terminal cancer].

PubMed

Ottesen, S; Monrad, L

1992-05-30

Simultaneous pain, nausea and vomiting are not uncommon in terminal suffering requiring treatment with various compounds of analgesics and antiemetics. At Baerum Hospital the pump reservoirs for continuous, subcutaneous drug delivery are routinely filled by the hospital pharmacist. We examined the physico-chemical stability of various concentrations of mixtures of morphine-metoclopramide and morphine-metoclopramide-haloperidol at 25 degrees C. We found good stability for at least seven days. Addition of haloperidol seems to reduce stability. Plain morphine-haloperidol solutions are unstable. Split products were not found in any of the mixtures. We also examined the osmolality of current clinical compounds, focusing on local irritant effect at the infusion site. All solutions except for one with a high concentration of haloperidol were found to be close to isoosmolarl.

Determination of several families of phytochemicals in different pre-cooked convenience vegetables: effect of lifetime and cooking.

PubMed

Alarcón-Flores, M Isabel; Hernández-Sánchez, Francisco; Romero-González, Roberto; Plaza-Bolaños, Patricia; Martínez Vidal, J Luis; Garrido Frenich, Antonia

2014-11-01

Phytochemicals content, including several families such as phenolic acids, isoflavones, flavones, flavonols, isothiocyanates, and glucosinolates, was determined in pre-cooked convenience vegetables by ultra high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS). It was observed that there is not a common behavior of the individual concentration of phytochemicals during the lifetime and cooking of the matrix, and compounds change their concentration without a specific trend. It was observed that neither lifetime nor cooking process have significant effects on the total content of phytochemicals except in broccoli, although some changes in the individual content of the target compounds were observed, suggesting that interconversion processes could be performed during the lifetime and/or cooking process of the product.

Volatile concentrations in variably vesicular pyroclasts from the Rotongaio ash (181 AD Taupo eruption): did shallow magma degassing trigger exceptionally violent phreatomagmatic activity?

NASA Astrophysics Data System (ADS)

Tuffen, Hugh; Houghton, Bruce F.; Dingwellp, Donald B.; Pinkerton, Harry

2010-05-01

Measurement of dissolved volatile concentrations in pyroclasts has formed the basis of our understanding of the links between magma degassing and the explosivity of silicic eruptions[1]. To date these studies have focussed exclusively on the densest pyroclastic obsidians, which comprise on a tiny proportion of the erupted products, in order to bypass the difficulty of analysing vesicular material. As a consequence, crucial information is missing about how degassing in the densest clasts relates to the behaviour of the bulk of the magma volume. To overcome this shortcoming, the volatile content of variably vesicular pyroclasts from the Rotongaio ash has been analysed using both micro-analytical (SIMS, synchrotron FTIR) and bulk techniques (TGA-MS). The Rotongaio ash was an exceptionally violent phase of phreatomagmatic activity during the 181 AD rhyolitic eruption of Taupo (New Zealand), the most powerful worldwide in the last 5000 years. The Rotongaio phase involved opening of new vents beneath Lake Taupo and the ash is characterised by a wide range of clast vesicularities (<10 to ~80 % by volume). Volatile measurement was challenging due to the high bubble number densities and small clast sizes. The mismatch between the water content of matrix glasses measured using bulk and micro-analytical techniques reflects pervasive post-eruption hydration of vesicle walls, which is most problematic at high vesicularities. Micron-scale maps of water concentration variations around vesicles in 30-50 vol % vesicular samples were acquired using SIMS. They indicate strong hydration within ~5 microns of vesicle walls, with pockets of unhydrated glass remaining in the thickest septa. Analysis of these unhydrated domains allowed robust measurement of water contents in pyroclasts ranging from ~1 to >50 vol % vesicles. Matrix glasses had largely degassed (0.19-0.49 wt % H2O, compared with an initial concentration in melt inclusions of ~3.6 wt %). The water contents measured using SIMS decreased systematically with increasing magma vesicularity. These results are fit well by a simple magma degassing model, in which a batch of magma first undergoes partial open-system degassing to a uniform water concentration of ~0.4 wt % H2O. Vesiculation then occurs with closed-system degassing, creating a negative relationship between vesicle content and the water content remaining in the melt. This model is consistent with the intrusion of a shallow cryptodome beneath Lake Taupo (depth ~100-200 metres) and prolonged stalling of magma at this shallow level. This was then followed by abrupt magma ascent and vesiculation, accompanied by interaction with the overlying lake water. Recent experiments have shown that the most violent interactions between rhyolitic magma and water may occur when the magma is highly viscous and prone to shear failure, as this creates the initial surface area for magma-water contact that results in explosive fuel-coolant interaction. The accumulation of a large volume (~1 km3) of degassed, highly-viscous rhyolitic magma directly beneath Lake Taupo may have therefore caused the exceptionally violent magma-water interaction that occurred during the Rotongaio phase. This reveals new links between magma degassing and the explosivity of eruptions when external water is involved, and illustrates the value of analysing pyroclastic material spanning a wide range of vesicularity in order to better reconstruct degassing systematics. References [1] Newman S. et al. (1988) J. Volcanol. Geotherm. Res. 35, 75-96. [2] Smith RT & Houghton BF (1995) Bull. Volcanol. 57, 432-439. [3] A. Austin-Erickson et al. (2008) J. Geophys. Res., 113, B11201.

Effects of Dissolved Organic Matter on Uptake and Translocation of Lead in Brassica chinensis and Potential Health Risk of Pb

PubMed Central

Li, Renying; Zhou, Zhigao; Xie, Xiaojin; Li, Yingxue; Zhang, Yaohong; Xu, Xianghua

2016-01-01

Dissolved organic matter (DOM) can affect the bioavailability of heavy metals in soil, especially in soils used for vegetable production, where intensive organic fertilization is applied. The present study examined the effects of DOM derived from commercial organic fertilizers (COF), cow manure (COM) and chicken manure (CHM), on uptake and translocation of lead (Pb) in Brassica chinensis in a pot experiment. The results indicate that DOM derived from CHM (DOMCHM) significantly increased Pb concentrations in roots of B. chinensis (p < 0.05). By contrast, there was no significant increase in shoot Pb concentration for all the DOM treatments except the high DOMCHM treatment in the soil with 800 mg·kg−1 Pb. Consistent with the Pb concentrations in shoots, translocation factor of Pb from soil to shoot and specific lead uptake (SLU) by B. chinensis were significantly increased for the high DOMCHM treatment in the high Pb soil, but not for other DOM treatments. Based on the results of this study, the application of DOM to the soil with 800 mg·kg−1 Pb could result in an increase in total Pb annually ingested by the inhabitants of Nanjing City in the range of 2018–9640 kg, with the highest estimates resulting from the high DOMCHM treatment. This study suggests the risk may rise under some conditions as indicated in the high DOMCHM treatment and high Pb pollution level. PMID:27399753

Evaluation of minerals content of drinking water in Malaysia.

PubMed

Azlan, Azrina; Khoo, Hock Eng; Idris, Mohd Aizat; Ismail, Amin; Razman, Muhammad Rizal

2012-01-01

The drinking and mineral water samples obtained from different geographical locations had concentrations of the selected minerals lower than the standard limits, except for manganese, arsenic, and fluoride. The concentrations of manganese and arsenic in two mineral water samples were slightly higher than the standard international recommended limits. One mineral water sample had a fluoride concentration higher than the standard limits, whereas manganese was not detected in nine drinking and mineral water samples. Most of the selected minerals found in the tap water samples were below the international standard limits, except for iron and manganese. The concentrations of iron and manganese in the tap water samples were higher than the standard limits, which were obtained from one and three of the studied locations, respectively. The potable water obtained from various manufacturers and locations in Peninsular Malaysia is safe for consumption, as the minerals concentrations were below the standard limits prescribed by the Malaysian Food Regulations of 1985. The data obtained may also provide important information related to daily intake of these minerals from drinking water.

Evaluation of Minerals Content of Drinking Water in Malaysia

PubMed Central

Azlan, Azrina; Khoo, Hock Eng; Idris, Mohd Aizat; Ismail, Amin; Razman, Muhammad Rizal

2012-01-01

The drinking and mineral water samples obtained from different geographical locations had concentrations of the selected minerals lower than the standard limits, except for manganese, arsenic, and fluoride. The concentrations of manganese and arsenic in two mineral water samples were slightly higher than the standard international recommended limits. One mineral water sample had a fluoride concentration higher than the standard limits, whereas manganese was not detected in nine drinking and mineral water samples. Most of the selected minerals found in the tap water samples were below the international standard limits, except for iron and manganese. The concentrations of iron and manganese in the tap water samples were higher than the standard limits, which were obtained from one and three of the studied locations, respectively. The potable water obtained from various manufacturers and locations in Peninsular Malaysia is safe for consumption, as the minerals concentrations were below the standard limits prescribed by the Malaysian Food Regulations of 1985. The data obtained may also provide important information related to daily intake of these minerals from drinking water. PMID:22649292

Variation in chemical composition and physical characteristics of cereal grains from different genotypes.

PubMed

Rodehutscord, Markus; Rückert, Christine; Maurer, Hans Peter; Schenkel, Hans; Schipprack, Wolfgang; Bach Knudsen, Knud Erik; Schollenberger, Margit; Laux, Meike; Eklund, Meike; Siegert, Wolfgang; Mosenthin, Rainer

2016-01-01

Genotypes of cereal grains, including winter barley (n = 21), maize (n = 27), oats (n = 14), winter rye (n = 22), winter triticale (n = 21) and winter wheat (n = 29), were assayed for their chemical composition and physical characteristics as part of the collaborative research project referred to as GrainUp. Genotypes of one grain species were grown on the same site, except maize. In general, concentrations of proximate nutrients were not largely different from feed tables. The coefficient of variation (CV) for the ether extract concentration of maize was high because the data pool comprised speciality maize bred for its high oil content. A subset of 8 barley, 20 rye, 20 triticale and 20 wheat samples was analysed to differ significantly in several carbohydrate fractions. Gross energy concentration of cereal grains could be predicted from proximate nutrient concentration with good accuracy. The mean lysine concentration of protein was the highest in oats (4.2 g/16 g N) and the lowest in wheat (2.7 g/16 g N). Significant differences were also detected in the concentrations of macro elements as well as iron, manganese, zinc and copper. Concentrations of arsenic, cadmium and lead were below the limit of detection. The concentration of lower inositol phosphates was low, but some inositol pentaphosphates were detected in all grains. In barley, relatively high inositol tetraphosphate concentration also was found. Intrinsic phytase activity was the highest in rye, followed by triticale, wheat, barley and maize, and it was not detectable in oats. Substantial differences were seen in the thousand seed weight, test weight, falling number and extract viscoelasticity characteristics. The study is a comprehensive overview of the composition of different cereal grain genotypes when grown on the same location. The relevance of the variation in composition for digestibility in different animal species will be subject of other communications.

Source profiles for nonmethane organic compounds in the atmosphere of Cairo, Egypt.

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

Doskey, P. V.; Fukui, Y.; Sultan, M.

1999-07-01

Profiles of the sources of nonmethane organic compounds (NMOCs) were developed for emissions from vehicles, petroleum fuels (gasoline, liquefied petroleum gas (LPG), and natural gas), a petroleum refinery, a smelter, and a cast iron factory in Cairo, Egypt. More than 100 hydrocarbons and oxygenated hydrocarbons were tentatively identified and quantified. Gasoline-vapor and whole-gasoline profiles could be distinguished from the other profiles by high concentrations of the C{sub 5} and C{sub 6} saturated hydrocarbons. The vehicle emission profile was similar to the whole-gasoline profile, with the exception of the unsaturated and aromatic hydrocarbons, which were present at higher concentrations in themore » vehicle emission profile. High levels of the C{sub 2}-C{sub 4} saturated hydrocarbons, particularly n-butane, were characteristic features of the petroleum refinery emissions. The smelter and cast iron factory emissions were similar to the refinery emissions; however, the levels of benzene and toluene were greater in the former two sources. The LPG and natural gas emissions contained high concentrations of n-butane and ethane, respectively. The NMOC source profiles for Cairo were distinctly different from profiles for U.S. sources, indicating that NMOC source profiles are sensitive to the particular composition of petroleum fuels that are used in a location.« less

Assessment of the performance of a compact concentric spectrometer system for Atmospheric Differential Optical Absorption Spectroscopy

NASA Astrophysics Data System (ADS)

Whyte, C.; Leigh, R. J.; Lobb, D.; Williams, T.; Remedios, J. J.; Cutter, M.; Monks, P. S.

2009-08-01

A breadboard demonstrator of a novel UV/VIS grating spectrometer for atmospheric research has been developed based upon a concentric arrangement of a spherical meniscus lens, concave spherical mirror and curved diffraction grating suitable for a range of remote sensing applications from the ground or space. The spectrometer is compact and provides high optical efficiency and performance benefits over traditional instruments. The concentric design is capable of handling high relative apertures, owing to spherical aberration and coma being near zero at all surfaces. The design also provides correction for transverse chromatic aberration and distortion, in addition to correcting for the distortion called "smile", the curvature of the slit image formed at each wavelength. These properties render this design capable of superior spectral and spatial performance with size and weight budgets significantly lower than standard configurations. This form of spectrometer design offers the potential for an exceptionally compact instrument for differential optical absorption spectroscopy (DOAS) applications particularly from space (LEO, GEO orbits) and from HAPs or ground-based platforms. The breadboard demonstrator has been shown to offer high throughput and a stable Gaussian line shape with a spectral range from 300 to 450 nm at better than 0.5 nm resolution, suitable for a number of typical DOAS applications.

Heavy metal (As, Cd, Hg, Pb, Cu, Zn, Se) concentrations in muscle and bone of four commercial fish caught in the central Adriatic Sea, Italy.

PubMed

Perugini, Monia; Visciano, Pierina; Manera, Maurizio; Zaccaroni, Annalisa; Olivieri, Vincenzo; Amorena, Michele

2014-04-01

Heavy metal (As, Cd, Cu, Pb, Zn, Hg and Se) concentrations in the muscle and bone of four fish species (Mullus barbatus, Merluccius merluccius, Micromesistius poutassou, and Scomber scombrus) from the central Adriatic Sea were measured and the relationships between fish size (length and weight) and metal concentrations in the tissues were investigated. Samples were analyzed by inductively coupled plasma-atomic emission spectrophotometry with automatic dual viewing. In the muscle, results of linear regression analysis showed that, except for mercury, significant relationships between metal concentrations and fish size were negative. Only mercury levels were positively correlated with Atlantic mackerel size (p < 0.05). No significant variations of heavy metal concentrations were observed in muscles of the examined species, but a significant difference (p < 0.01) was found for As, Cd, Pb, and Se concentrations in bone. All the investigated metals showed higher values in the muscle than in bone, except for lead and zinc. Regarding cadmium, lead, and mercury maximum levels, set for the edible portion by European legislation, several samples exceeded these values, confirming the heavy metal presence in species caught near the Jabuka Pit.

Quality of ground water in the Puget sound region, Washington, 1981

USGS Publications Warehouse

Turney, G.L.

1986-01-01

Groundwater from more than 100 sites in the Puget Sound region, Washington, was sampled and analyzed in 1981 for pH, specific conductance, and concentrations of fecal coliform bacteria, major ions, and dissolved iron, manganese, and nitrate. 20% of the samples were analyzed for concentrations of dissolved trace metals including aluminum, arsenic, barium, cadmium, chromium, copper, lead, mercury, selenium, silver, and zinc. The predominant water types were calcium bicarbonate and calcium-magnesium bicarbonate. Some wells in San Juan and Island Counties contained sodium chloride as a result of seawater intrusion. Dissolved solids concentrations were generally < 150 mg/L. Iron concentrations > 300 micrograms/L in 14% of all samples. Manganese concentrations > 50 micrograms/L in 40% of all samples. Trace-metal concentrations were generally < 10 mg/L , except for barium, copper, lead, and zinc. Nitrate concentrations were < 1.0 mg/L in water for over 75% of the sites. Concentrations > 1.0 mg/L in samples from Skagit, Whatcom , and Pierce Counties, were probably due to agricultural activities or septic tanks. Fecal coliform bacteria were detected in isolated instances. EPA drinking water regulations were exceeded only in isolated instances, except for widespread excessive iron and manganese concentrations. The historical data for the region were also evaluated for the same constituents. There are quantitative differences between historical and 1981 data, but they may be due to inconsistencies in data collection and analytical methods. (Author 's abstract)

Toxicity of sulfadiazine and copper and their interaction to wheat (Triticum aestivum L.) seedlings.

PubMed

Xu, Yonggang; Yu, Wantai; Ma, Qiang; Zhou, Hua; Jiang, Chunming

2017-08-01

A pot experiment was carried out to investigate the single and combined effect of different concentrations of sulfadiazine (SDZ) (1 and 10mgkg -1 ) and copper (Cu) (20 and 200mgkg -1 ) stresses on growth, hydrogen peroxide (H 2 O 2 ), malondialdehyde (MDA), antioxidant enzyme activities of wheat seedlings and their accumulation. High SDZ or Cu level significantly inhibited the growth of wheat seedlings, but the emergence rate was only inhibited by high SDZ level. The presence of Cu reduced the accumulation of SDZ, whereas the effect of SDZ on the accumulation of Cu depended on their concentrations. Low Cu level significantly increased the chlorophyll content, while high Cu level or both SDZ concentrations resulted in a significant decrease in the chlorophyll content as compared to the control. Additionally, H 2 O 2 and MDA contents increased with the elevated SDZ or Cu level. The activities of superoxide dismutase, peroxidase and catalase were also stimulated by SDZ or Cu except for the aerial part treated by low Cu level and root treated by high SDZ level. The joint toxicity data showed that the toxicity of SDZ to wheat seedlings was generally alleviated by the presence of Cu, whereas the combined toxicity of SDZ and Cu was larger than equivalent Cu alone. Copyright © 2017. Published by Elsevier Inc.

Water quality assessment of a small peri-urban river using low and high frequency monitoring.

PubMed

Ivanovsky, A; Criquet, J; Dumoulin, D; Alary, C; Prygiel, J; Duponchel, L; Billon, G

2016-05-18

The biogeochemical behaviors of small rivers that pass through suburban areas are difficult to understand because of the multi-origin inputs that can modify their behavior. In this context, a monitoring strategy has been designed for the Marque River, located in Lille Metropolitan area of northern France, that includes both low-frequency monitoring over a one-year period (monthly sampling) and high frequency monitoring (measurements every 10 minutes) in spring and summer. Several environmental and chemical parameters are evaluated including rainfall events, river flow, temperature, dissolved oxygen, turbidity, conductivity, nutritive salts and dissolved organic matter. Our results from the Marque River show that (i) it is impacted by both urban and agricultural inputs, and as a consequence, the concentrations of phosphate and inorganic nitrogen have degraded the water quality; (ii) the classic photosynthesis/respiration processes are disrupted by the inputs of organic matter and nutritive salts; (iii) during dry periods, the urban sewage inputs (treated or not) are more important during the day, as indicated by higher river flows and maximal concentrations of ammonium; (iv) phosphate concentrations depend on oxygen contents in the river; (v) high nutrient concentrations result in eutrophication of the Marque River with lower pH and oxygen concentrations in summer. During rainfalls, additional inputs of ammonium, biodegradable organic matter as well as sediment resuspension result in anoxic events; and finally (vi) concentrations of nitrate are approximately constant over the year, except in winter when higher inputs can be recorded. Having better identified the processes responsible for the observed water quality, a more informed remediation effort can be put forward to move this suburban river to a good status of water quality.

Nanostructured protic ionic liquids retain nanoscale features in aqueous solution while precursor Brønsted acids and bases exhibit different behavior.

PubMed

Greaves, Tamar L; Kennedy, Danielle F; Weerawardena, Asoka; Tse, Nicholas M K; Kirby, Nigel; Drummond, Calum J

2011-03-10

Small- and wide-angle X-ray scattering (SWAXS) has been used to investigate the effect that water has on the nanoscale structure of protic ionic liquids (PILs) along with their precursor Brønsted acids and bases. The series of PILs consisted of primary, secondary, and tertiary alkylammonium cations in conjunction with formate, nitrate, or glycolate anions. Significant differences were observed for these systems. The nanoscale aggregates present in neat protic ionic liquids were shown to be stable in size on dilution to high concentrations of water, indicating that the water is localized in the ionic region and has little effect on the nonpolar domains. The Brønsted acid-water solutions did not display nanostructure at any water concentration. Primary amine Brønsted bases formed aggregates in water, which generally displayed characteristics of poorly structured microemulsions or a form of bicontinuous phase. Exceptions were butyl- and pentylamine with high water concentrations, for which the SWAXS patterns fitted well to the Teubner-Strey model for microemulsions. Brønsted base amines containing multiple alkyl chains or hydroxyl groups did not display nanostructure at any water concentration. IR spectroscopy was used to investigate the nature of water in the various solutions. For low PIL concentrations, the water was predominately present as bulk water for PIL molar fractions less than 0.4-0.5. At high PIL concentrations, in addition to the bulk water, there was a significant proportion of perturbed water, which is water influenced in some way by the cations and anions. The molecular state of the water in the studied amines was predominately present as bulk water, with smaller contributions from perturbed water than was seen in the PILs. © 2011 American Chemical Society

Urinary analysis reveals high deoxynivalenol exposure in pregnant women from Croatia.

PubMed

Sarkanj, Bojan; Warth, Benedikt; Uhlig, Silvio; Abia, Wilfred A; Sulyok, Michael; Klapec, Tomislav; Krska, Rudolf; Banjari, Ines

2013-12-01

In this pilot survey the levels of various mycotoxin biomarkers were determined in third trimester pregnant women from eastern Croatia. First void urine samples were collected and analysed using a "dilute and shoot" LC-ESI-MS/MS multi biomarker method. Deoxynivalenol (DON) and its metabolites: deoxynivalenol-15-glucuronide and deoxynivalenol-3-glucuronide were detected in 97.5% of the studied samples, partly at exceptionally high levels, while ochratoxin A was found in 10% of the samples. DON exposure was primarily reflected by the presence of deoxynivalenol-15-glucuronide with a mean concentration of 120 μg L(-1), while free DON was detected with a mean concentration of 18.3 μg L(-1). Several highly contaminated urine samples contained a third DON conjugate, tentatively identified as deoxynivalenol-7-glucuronide by MS/MS scans. The levels of urinary DON and its metabolites measured in this study are the highest ever reported, and 48% of subjects were estimated to exceed the provisional maximum tolerable daily intake (1 μg kg(-1) b.w.). Copyright © 2013 Elsevier Ltd. All rights reserved.

Reverse membrane bioreactor: Introduction to a new technology for biofuel production.

PubMed

Mahboubi, Amir; Ylitervo, Päivi; Doyen, Wim; De Wever, Heleen; Taherzadeh, Mohammad J

2016-01-01

The novel concept of reverse membrane bioreactors (rMBR) introduced in this review is a new membrane-assisted cell retention technique benefiting from the advantageous properties of both conventional MBRs and cell encapsulation techniques to tackle issues in bioconversion and fermentation of complex feeds. The rMBR applies high local cell density and membrane separation of cell/feed to the conventional immersed membrane bioreactor (iMBR) set up. Moreover, this new membrane configuration functions on basis of concentration-driven diffusion rather than pressure-driven convection previously used in conventional MBRs. These new features bring along the exceptional ability of rMBRs in aiding complex bioconversion and fermentation feeds containing high concentrations of inhibitory compounds, a variety of sugar sources and high suspended solid content. In the current review, the similarities and differences between the rMBR and conventional MBRs and cell encapsulation regarding advantages, disadvantages, principles and applications for biofuel production are presented and compared. Moreover, the potential of rMBRs in bioconversion of specific complex substrates of interest such as lignocellulosic hydrolysate is thoroughly studied. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Impact of non-constant concentration exposure on lethality of inhaled hydrogen cyanide.

PubMed

Sweeney, Lisa M; Sommerville, Douglas R; Channel, Stephen R

2014-03-01

The ten Berge model, also known as the toxic load model, is an empirical approach in hazard assessment modeling for estimating the relationship between the inhalation toxicity of a chemical and the exposure duration. The toxic load (TL) is normally expressed as a function of vapor concentration (C) and duration (t), with TL equaling C(n) × t being a typical form. Hypothetically, any combination of concentration and time that yields the same "toxic load" will give a constant biological response. These formulas have been developed and tested using controlled, constant concentration animal studies, but the validity of applying these assumptions to time-varying concentration profiles has not been tested. Experiments were designed to test the validity of the model under conditions of non-constant acute exposure. Male Sprague-Dawley rats inhaled constant or pulsed concentrations of hydrogen cyanide (HCN) generated in a nose-only exposure system for 5, 15, or 30 min. The observed lethality of HCN for the 11 different C versus t profiles was used to evaluate the ability of the model to adequately describe the lethality of HCN under the conditions of non-constant inhalation exposure. The model was found to be applicable under the tested conditions, with the exception of the median lethality of very brief, high concentration, discontinuous exposures.

Non-methane hydrocarbons at a high-altitude rural site in the Mediterranean (Greece)

NASA Astrophysics Data System (ADS)

Moschonas, Nektarios; Glavas, Sotirios

Acetylene, C 3-C 10 paraffins, olefins, aromatic hydrocarbons and the biogenic isoprene, were determined in six sampling periods from May to October in 1996-1997. The concentrations of the determined species were generally lower than those measured in southeastern US and western France, but higher than those measured in more remote regions. Acetylene and C 3-C 5 hydrocarbons exhibited seasonal variation with higher concentrations in the late October sampling period. The aromatic hydrocarbons, except benzene, exhibited maximum concentrations in the summer. Isoprene had maximum concentrations in the summer, with its concentration linearly increasing as a function of the logarithm of temperature, in agreement with past studies. Its emission flux was calculated to be on the lower end of similar studies in US. The main destruction route of all hydrocarbons was determined to be due to their photochemical reactions. The photochemical reactivity, calculated in terms of propylene equivalent concentration, was in the summer dominated by isoprene which accounts for 69% of the total, aromatics with 16%, olefins with 11% and paraffins with 4%. In the May and October periods, the aromatics contributed the most (˜37%) to the photochemical reactivity. Air mass back trajectories indicated higher concentrations when air masses arrived from northwestern and northeastern, compared to southern, directions.

Arsenic geochemistry of groundwater in Southeast Asia.

PubMed

Kim, Kyoung-Woong; Chanpiwat, Penradee; Hanh, Hoang Thi; Phan, Kongkea; Sthiannopkao, Suthipong

2011-12-01

The occurrence of high concentrations of arsenic in the groundwater of the Southeast Asia region has received much attention in the past decade. This study presents an overview of the arsenic contamination problems in Vietnam, Cambodia, Lao People's Democratic Republic and Thailand. Most groundwater used as a source of drinking water in rural areas has been found to be contaminated with arsenic exceeding the WHO drinking water guideline of 10 μg·L(-1). With the exception of Thailand, groundwater was found to be contaminated with naturally occurring arsenic in the region. Interestingly, high arsenic concentrations (> 10 μg·L(-1)) were generally found in the floodplain areas located along the Mekong River. The source of elevated arsenic concentrations in groundwater is thought to be the release of arsenic from river sediments under highly reducing conditions. In Thailand, arsenic has never been found naturally in groundwater, but originates from tin mining activities. More than 10 million residents in Southeast Asia are estimated to be at risk from consuming arsenic-contaminated groundwater. In Southeast Asia, groundwater has been found to be a significant source of daily inorganic arsenic intake in humans. A positive correlation between groundwater arsenic concentration and arsenic concentration in human hair has been observed in Cambodia and Vietnam. A substantial knowledge gap exists between the epidemiology of arsenicosis and its impact on human health. More collaborative studies particularly on the scope of public health and its epidemiology are needed to conduct to fulfill the knowledge gaps of As as well as to enhance the operational responses to As issue in Southeast Asian countries.

Determination of macro and trace elements in multivitamin dietary supplements by high-resolution continuum source graphite furnace atomic absorption spectrometry with slurry sampling.

PubMed

Krawczyk, Magdalena

2014-01-01

In this research, three different commercially available multivitamin dietary supplements were analyzed by high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GFAAS) with slurry sampling. The concentrations of Cr, Cu, Fe, Mn, and Se were determined and compared to the amounts stated by producers. The safety of multivitamin dietary supplements depends on various factors including the manufacturing process and the purity and origins of the raw ingredients. For this reason, this research determined concentrations of several toxic elements (As, Cd, and Pb). Microwave-assisted high pressure Teflon bomb digestion was used to determine total amounts of elements in samples. Samples were prepared as slurries at a concentration of 0.1% (m/v) for macro elements (Cr, Cu, Fe, Mn, and Se) and at a concentration of % (m/v) for trace elements (As, Cd, and Pb) in acidic media (3M HNO3). The influence of acid concentration, Triton X-100 addition, sonication time, and sonication power on absorbance was investigated. The accuracy of this method was validated by analyses of NRCC LUTS-1 (Lobster hepatopancreas), NRCC DORM-1 (Dogfish Muscle), NRCC DOLT-2 (Dogfish Liver), NBS SRM 1570 (Spinach Leaves) and NBS SRM 1573 (Tomato Leaves) certified reference materials. The measured elements contents in these reference materials (except NRCC DOLT-2) were in satisfactory agreement with the certified values according to the t-test for a 95% confidence level. Copyright © 2013 Elsevier B.V. All rights reserved.

Observations of high droplet number concentrations in Southern Ocean boundary layer clouds

NASA Astrophysics Data System (ADS)

Chubb, T.; Huang, Y.; Jensen, J.; Campos, T.; Siems, S.; Manton, M.

2015-09-01

Data from the standard cloud physics payload during the NSF/NCAR High-performance Instrumented Airborne Platform for Environmental Research (HIAPER) Pole-to-Pole Observations (HIPPO) campaigns provide a snapshot of unusual wintertime microphysical conditions in the boundary layer over the Southern Ocean. On 29 June 2011, the HIAPER sampled the boundary layer in a region of pre-frontal warm air advection between 58 and 48° S to the south of Tasmania. Cloud droplet number concentrations were consistent with climatological values in the northernmost profiles but were exceptionally high for wintertime in the Southern Ocean at 100-200 cm-3 in the southernmost profiles. Sub-micron (0.0625 m s-1) were most likely responsible for production of sea spray aerosol which influenced the microphysical properties of the boundary layer clouds. The smaller size and higher number concentration of cloud droplets is inferred to increase the albedo of these clouds, and these conditions occur regularly, and are expected to increase in frequency, over windy parts of the Southern Ocean.

Urbanization Changes the Temporal Dynamics of Nutrients and Water Chemistry

NASA Astrophysics Data System (ADS)

Steele, M.; Badgley, B.

2017-12-01

Recent studies find that urban development alters the seasonal dynamics of nutrient concentrations, where the highest concentrations of nitrogen occurred during the winter in urban watersheds, rather than the summer. However, the effects of urbanization on the seasonal concentrations of other nutrients and chemical components is unknown. Therefore, to determine how urbanization changes the seasonal dynamics, once a week we measured concentrations of dissolved organic carbon (DOC), nutrients (NO3, DON, TN, PO4), base cations (Ca, Mg, Na, K), anions (F, Cl, SO4), pH, sediment, temperature, conductivity, and dissolved oxygen (DO) of nine urban, agricultural, and minimally developed watersheds in southwest Virginia, USA. We found that urbanization disrupted the seasonal dynamics of all metrics, except DON, PO4, Ca, sediment, and DO, where some shifted to high concentrations during the winter (Cl, conductivity), highs during late winter or spring (DOC, Na), a season low (TN, SO4, NO3) or high (NH4) during the summer, or remained more constant throughout the year compared to the reference watersheds (Mg, K, pH). The complex changes in seasonal dynamics coincide with a decoupling of common correlations between constituents; for example, DO and NO3 are negatively correlated in reference watersheds (NO3 increases, DO decreases), but positively correlated in urban watersheds. These results suggest that as watersheds become more intensely developed, the influence of natural drivers like temperature and vegetation become steadily overcome by the influence of urban drivers like deicing salts and wastewater leakage, which exert increasing control of seasonal water quality and aquatic habitat.

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

Samoylenko, Vitaliy V., E-mail: samoylenko.vitaliy@mail.ru; Lenivtseva, Olga G., E-mail: lenivtseva-olga@mail.ru; Polyakov, Igor A., E-mail: status9@mail.ru

In this paper structural investigations and mechanical tests of Ti-Ta-Zr coatings obtained on surfaces of cp-titanium workpieces were carried out. It was found that the coatings had a dendrite structure; investigations at high-power magnifications revealed a platelet structure. An increase of tantalum concentration led to refinement of structural components. The microhardness level of all coatings, excepting a specimen with the maximum tantalum content, was 370 HV. The microhardness of this coating reached 400 HV. The ultimate tensile strength of cladded layers varied from 697 to 947 MPa. Adhesion tests showed that bimetallic composites were characterized by high bond strength of claddedmore » layers to the substrate, which exceeded cp-titanium strength characteristics.« less

Oxygen Inhibition of Photosynthesis and Stimulation of Photorespiration in Soybean Leaf Cells

PubMed Central

Servaites, Jerome C.; Ogren, William L.

1978-01-01

The occurrence of photorespiration in soybean (Glycine max [L.] Merr.) leaf cells was demonstrated by the presence of an O2-dependent CO2 compensation concentration, a nonlinear time course for photosynthetic 14CO2 uptake at low CO2 and high O2 concentrations, and an O2 stimulation of glycine and serine synthesis which was reversed by high CO2 concentration. The compensation concentration was a linear function of O2 concentration and increased as temperature increased. At atmospheric CO2 concentration, 21% O2 inhibited photosynthesis at 25 C by 27%. Oxygen inhibition of photosynthesis was competitive with respect to CO2 and increased with increasing temperature. The Km (CO2) of photosynthesis was also temperature-dependent, increasing from 12 μm CO2 at 15 C to 38 μm at 35 C. In contrast, the Ki (O2) was similar at all temperatures. Oxygen inhibition of photosynthesis was independent of irradiance except at 10 mm bicarbonate and 100% O2, where inhibition decreased with increasing irradiance up to the point of light saturation of photosynthesis. Concomitant with increasing O2 inhibition of photosynthesis was an increased incorporation of carbon into glycine and serine, intermediates of the photorespiratory pathway, and a decreased incorporation into starch. The effects of CO2 and O2 concentration and temperature on soybean cell photosynthesis and photorespiration provide further evidence that these processes are regulated by the kinetic properties of ribulose-1,5-diphosphate carboxylase with respect to CO2 and O2. PMID:16660238

Substituent effect on photophysical properties of bi-1,3,4-oxadiazole derivatives in solution

NASA Astrophysics Data System (ADS)

Chen, Fangyi; Tian, Taiji; Zhao, Chengxiao; Bai, Binglian; Li, Min; Wang, Haitao

2016-04-01

A series of phenyl substituted bi-1,3,4-oxadiazole derivatives were designed and synthesized; the effect of substituent on the photophysical properties and molecular electronic structures was fully studied by the combination of experimental techniques and theoretical calculations. Compared to parent compound without any substituent (BOXD), fluoro-substituent shows little effect on the absorption and emission spectra, whilst a little larger spectral red-shift could be observed for methoxy-, nitro-substituted derivatives and thienyl-substituted bi-1,3,4-oxadiazole (TBOXD). These spectral changes can be well explained by theoretically calculated HOMO and LUMO energy level changes. All these molecules show high fluorescence quantum yield except for nitro-substituted derivative in dilute solutions. The quantum yield of BOXD changes with the concentration and exhibits a high value at the concentrated solution. This work revealed the influence of substituent on the photophysical properties of bi-1,3,4-oxadizaole derivatives in dilute solutions and provided guidance for designing molecules with potential application.

Multivariate analysis of heavy metal contents in soils, sediments and water in the region of Meknes (central Morocco).

PubMed

Tahri, M; Benyaïch, F; Bounakhla, M; Bilal, E; Gruffat, J J; Moutte, J; Garcia, D

2005-03-01

Concentrations of Al, Fe, Cr, Cu, Ni, Pb and Zn in soils, sediments and water samples collected along the Oued Boufekrane river (Meknes, central Morocco) were determined. In soils, a homogeneous distribution of metal concentrations was observed throughout the study area except for Pb, which presents high enrichment at sites located at the vicinity of a main highway. In sediments, high enrichment, with respect to upstream sites, were observed downstream of the city of Meknes for Al, Cr, Fe and Ni and inside the city for Cu, Zn and Pb. In water samples, the metal contents showed to correlate with their homologues in sediments suggesting that the metal contents in water and sediments have identical origins. Descriptive statistics and multivariate analysis (principal factor method, PFM) were used to assist the interpretation of elemental data. This allowed the determination of the correlations between the metals and the identification of three main factor loadings controlling the metal variability in soils and sediments.

Rumen escape of methionine and lysine administered intraruminally to growing double-muscled Belgian Blue bulls.

PubMed

Froidmont, Eric; Rondia, Pierre; Théwis, André; Beckers, Yves

2002-01-01

In many dietary conditions, methionine (Met) and lysine (Lys) are the most limiting amino acids (AA) for ruminants. The AA protected from ruminal fermentation are not commercially available, with the exception of Met which is not always economical, especially for meat production. This study measured ruminal escape of free Met and Lys supplemented intraruminally to fast growing bulls. Six double-muscled Belgian Blue bulls, fed a high concentrate diet and fitted with a rumen cannula, received free Met (40 g x d(-1)) and free Lys (60 g x d(-1)), individually or simultaneously, in a duplicated Latin square design. The mean ruminal escape of Met and Lys reached 37 and 45% respectively, and did not differ if administered separately or together. Plasma Lys and Met concentrations were increased by 504 and 126%, respectively. Substantial proportions of free AA escaped ruminal fermentation and were available for absorption from the small intestine when they were administered at physiologically high levels.

Occurrence of 95 pharmaceuticals and transformation products in urban groundwaters underlying the metropolis of Barcelona, Spain.

PubMed

López-Serna, Rebeca; Jurado, Anna; Vázquez-Suñé, Enric; Carrera, Jesus; Petrović, Mira; Barceló, Damià

2013-03-01

The present paper presents the occurrence of 72 pharmaceuticals and 23 transformation products (TPs) in groundwaters (GWs) underlying the city of Barcelona, Spain. Thirty-one samples were collected under different districts, and at different depths. Aquifers with different geologic features and source of recharge were included, i.e., natural bank filtration, infiltration from wastewater and water supply pipes, rainfall recharge, etc. Antibiotics were the most frequently found compounds detected at levels reaching 1000 ng L(-1). Natural bank filtration from the river that receives large amounts of effluents from waste water treatment plants (WWTPs), turned out being the most influencing source of contamination, thus GW showed high range of compounds and concentrations as high as or even higher than in the river itself. In general, TPs were found at lower concentrations than the corresponding parent compounds, with some exceptions, such as 4OH propranolol and enalaprilat. Copyright © 2012 Elsevier Ltd. All rights reserved.

Struvite Crystallization of Anaerobic Digestive Fluid of Swine Manure Containing Highly Concentrated Nitrogen

PubMed Central

Lee, Eun Young; Oh, Min Hwan; Yang, Seung-Hak; Yoon, Tae Han

2015-01-01

In this study, the optimal operation factors for struvite crystallization for removing and recovering nitrogen and phosphorus from anaerobic digestive fluid of swine manure containing highly concentrated nitrogen was determined. Every experiment for the struvite crystallization reaction was conducted by placing 1,000 mL of digestion fluid in a 2,000 mL Erlenmeyer flask at various temperatures, pH, and mixing speed. Except for special circumstances, the digestion fluid was centrifuged (10,000 rpm, 10 min) and then the supernatant was used for the experiment at room temperature and 100 rpm. The optimal mole ratio of PO43−:Mg2+ was 1:1.5, and the pH effect ranging from 9 to 11 was similar, when mixed for 1 hour. Under this condition, the removal efficiency of NH4+-N and PO43−-P was 40% and 88.6%, respectively. X-shaped crystal was observed by light and scanning electron microscopy. In addition, struvite crystal structure was confirmed through X-ray diffraction analysis. PMID:26104412

Pollutant impacts to Cape Hatteras National Seashore from urban runoff and septic leachate.

PubMed

Mallin, Michael A; McIver, Matthew R

2012-07-01

The sandy barrier islands of Cape Hatteras National Seashore, USA, attract large seasonal influxes of tourists, and are host to numerous motels, rentals and second homes. To investigate the impacts of nearby urbanization on public trust waters, sampling was conducted in nine brackish water bodies within this coastal national park. A large tidal urban ditch delivered runoff-driven fecal-contaminated water directly into public beach waters. At all sites except the control, ammonium, phosphorus and fecal bacteria concentrations were high, strongly seasonal and significantly correlated with community water usage, indicating that increased septic tank usage led to increased pollutant concentrations in area waterways. Nutrients from septic systems caused ecosystem-level problems from algal blooms, BOD, and hypoxia while fecal microbes created potential human health problems. Septic system usage is widespread in sensitive coastal areas with high water tables and sandy soils and alternatives to standard septic systems must be required to protect human health and the environment. Copyright © 2012 Elsevier Ltd. All rights reserved.

Simultaneous analysis of tropane alkaloids in teas and herbal teas by liquid chromatography coupled to high-resolution mass spectrometry (Orbitrap).

PubMed

Romera-Torres, Ana; Romero-González, Roberto; Martínez Vidal, José Luis; Garrido Frenich, Antonia

2018-05-01

A new method has been developed for the simultaneous determination of 13 tropane alkaloids in tea and herbal teas using high-performance liquid chromatography coupled to an Exactive-Orbitrap analyzer. A mixture of methanol, water, and formic acid was used for the extraction of the target compounds followed by a solid-phase extraction step. The validated method provided recoveries from 75 to 128% with intra- and interday precision lower than or equal to 24% (except for apoatropine). Limits of quantification ranged from 5 to 20 μg/kg. Eleven tea and herbal tea samples and two contaminated samples with Datura stramonium seeds were analyzed. Tropane alkaloids were detected in six samples with concentrations from 5 (apoatropine) to 4340 μg/kg (sum of physoperuvine, pseudotropine, and tropine), whereas concentrations from 5 (apoatropine) to 1725 μg/kg (sum of physoperuvine, pseudotropine, and tropine) were found in the contaminated samples. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mechanical properties and solubility in water of corn starch-collagen composite films: Effect of starch type and concentrations.

PubMed

Wang, Kun; Wang, Wenhang; Ye, Ran; Liu, Anjun; Xiao, Jingdong; Liu, Yaowei; Zhao, Yana

2017-02-01

This study investigated the possibility of enhancing the properties of collagen with three different maize starches: waxy maize starch, normal starch, and high amylose starch. Scanning electron microscopy images revealed that starch-collagen films had a rougher surface compared to pure collagen films which became smoother upon heating. Amylose starch and normal starch increased the tensile strength of unheated collagen films in both dry and wet states, while all starches increased tensile strength of collagen film by heating. Depending upon the amylose content and starch concentrations, film solubility in water decreased with the addition of starch. DSC thermograms demonstrated that addition of all starches improved the thermal stability of the collagen film. Moreover, X-ray diffraction results indicated that except for high amylose starch, the crystallinity of both starch and collagen was significantly decreased when subject to heating. FTIR spectra indicated that intermolecular interactions between starch and collagen were enhanced upon heating. Copyright © 2016 Elsevier Ltd. All rights reserved.

Selenium-enriched durum wheat improves the nutritional profile of pasta without altering its organoleptic properties.

PubMed

De Vita, Pasquale; Platani, Cristiano; Fragasso, Mariagiovanna; Ficco, Donatella Bianca Maria; Colecchia, Salvatore Antonio; Del Nobile, Matteo Alessandro; Padalino, Lucia; Di Gennaro, Spartaco; Petrozza, Angelo

2017-01-01

Two field experiments were conducted over three growing seasons (2006-07, 2008-09 and 2009-10) to evaluate Se-enriched pasta through foliar fertilization at various rates and timing of application on 4 durum wheat varieties. Our findings confirm the effectiveness of foliar Se fertilization to increase Se concentrations in durum wheat grain, even at high Se rates (120gSeha(-1)). Se fortification was significant across different genotypes, with greater Se accumulation in landraces ('Timilia') and obsolete varieties ('Cappelli'), with respect to modern varieties. The Se content in the grain was increased by up to 35-fold that of the untreated control. The Se concentration decreased during milling (11%), while processing and cooking of pasta did not show significant decreases. This biofortification stategy had no effects on grain quality parameters, except for reduced gluten index in the high-gluten variety PR22D89, as well as for the sensorial properties of the spaghetti. Copyright © 2016 Elsevier Ltd. All rights reserved.

Deposition and accumulation of airborne organic contaminants in Yosemite National Park, Calfornia

USGS Publications Warehouse

Mast, Alisa M.; Alvarez, David A.; Zaugg, Steven D.

2012-01-01

Deposition and accumulation of airborne organic contaminants in Yosemite National Park were examined by sampling atmospheric deposition, lichen, zooplankton, and lake sediment at different elevations. Passive samplers were deployed in high-elevation lakes to estimate surface-water concentrations. Detected compounds included current-use pesticides chlorpyrifos, dacthal, and endosulfans and legacy compounds chlordane, dichlorodiphenyltrichloroethane-related compounds, dieldrin, hexachlorobenzene, and polychlorinated biphenyls. Concentrations in snow were similar among sites and showed little variation with elevation. Endosulfan concentrations in summer rain appeared to coincide with application rates in the San Joaquin Valley. More than 70% of annual pesticide inputs from atmospheric deposition occurred during the winter, largely because most precipitation falls as snow. Endosulfan and chlordane concentrations in lichen increased with elevation, indicating that mountain cold-trapping might be an important control on accumulation of these compounds. By contrast, chlorpyrifos concentrations were inversely correlated with elevation, indicating that distance from source areas was the dominant control. Sediment concentrations were inversely correlated with elevation, possibly because of the organic carbon content of sediments but also perhaps the greater mobility of organic contaminants at lower elevations. Surface-water concentrations inferred from passive samplers were at sub-parts-per-trillion concentrations, indicating minimal exposure to aquatic organisms from the water column. Concentrations in sediment generally were low, except for dichlorodiphenyldichloroethane in Tenaya Lake, which exceeded sediment guidelines for protection of benthic organisms.

40 CFR 63.1253 - Standards: Storage tanks.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) National Emission Standards for Pharmaceuticals Production § 63.1253 Standards: Storage tanks. (a) Except... a combustion control device achieving an outlet TOC concentration, as calibrated on methane or the... achieve an outlet TOC concentration, as calibrated on methane or the predominant HAP, of 50 ppmv or less...

40 CFR 63.1253 - Standards: Storage tanks.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) National Emission Standards for Pharmaceuticals Production § 63.1253 Standards: Storage tanks. (a) Except... a combustion control device achieving an outlet TOC concentration, as calibrated on methane or the... achieve an outlet TOC concentration, as calibrated on methane or the predominant HAP, of 50 ppmv or less...

40 CFR 423.15 - New source performance standards (NSPS).

Code of Federal Regulations, 2014 CFR

2014-07-01

... performance standards: (a) The pH of all discharges, except once through cooling water, shall be within the... the concentration listed in the following table: Pollutant or pollutant property NSPS effluent... cleaning wastes times the concentration listed in the following table: Pollutant or pollutant property NSPS...

40 CFR 423.15 - New source performance standards (NSPS).

Code of Federal Regulations, 2013 CFR

2013-07-01

... performance standards: (a) The pH of all discharges, except once through cooling water, shall be within the... the concentration listed in the following table: Pollutant or pollutant property NSPS effluent... cleaning wastes times the concentration listed in the following table: Pollutant or pollutant property NSPS...

40 CFR 423.15 - New source performance standards (NSPS).

Code of Federal Regulations, 2012 CFR

2012-07-01

... performance standards: (a) The pH of all discharges, except once through cooling water, shall be within the... the concentration listed in the following table: Pollutant or pollutant property NSPS effluent... cleaning wastes times the concentration listed in the following table: Pollutant or pollutant property NSPS...

Has the phase-out of PBDEs affected their atmospheric levels? Trends of PBDEs and their replacements in the Great Lakes atmosphere.

PubMed

Ma, Yuning; Salamova, Amina; Venier, Marta; Hites, Ronald A

2013-10-15

Air and precipitation samples were collected every 12 days at five sites near the North American Great Lakes from 2005 to 2011 (inclusive) by the Integrated Atmospheric Deposition Network (IADN). The concentrations of polybrominated diphenyl ethers (PBDEs) and selected alternative brominated flame retardants [pentabromoethyl benzene (PBEB), hexabromobenzene (HBB), 1,2-bis(2,4,6-tribromophenoxy)ethane (TBE or BTBPE), decabromodiphenylethane (DBDPE), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB), and bis(2-ethylhexyl)-tetrabromo-phthalate (TBPH)] were measured in these samples. The concentrations of almost all of these flame retardants were related to the number of people within a 25 km radius of the sampling site, except for HBB, the concentrations of which were relatively high at Sturgeon Point, and PBEB, the concentrations of which were relatively high at Eagle Harbor. The temporal trends of all of these concentrations were variable. For example, BDE-47 vapor phase concentrations were increasing with doubling times of 5-10 years at Sturgeon Point, Sleeping Bear Dunes, and Eagle Harbor, but these concentrations were slowly decreasing in all phases at Chicago. The most consistent trend was for TBE, which showed concentrations that were unchanging or decreasing in all phases at all sites. TBPH concentrations in particles and HBB concentrations in precipitation were rapidly increasing at most sites with doubling times of ~2 years. The concentrations of DBDPE and BDE-209 were strongly and positively correlated, and the concentrations of TBB and TBPH were also strongly and positively correlated. The concentrations of TBB plus TBPH (representing Firemaster 550) and BDE-47, 85, 99, 100, 153, plus 154 (representing the withdrawn penta-BDE commercial mixture) were also strongly and positively correlated. These positive relationships indicate that the replacement of the deca-BDE commercial product by DBDPE and the penta-BDE product by Firemaster 550 have not yet become evident in the Great Lakes' atmospheric environment.

High levels of medium-chain chlorinated paraffins and polybrominated diphenyl ethers on the inside of several household baking oven doors.

PubMed

Gallistl, Christoph; Sprengel, Jannik; Vetter, Walter

2018-02-15

Fat obtained by wipe tests on the inner surface of 21 baking ovens from Stuttgart (Germany) were analyzed for halogenated flame retardants (HFRs), namely polybrominated diphenyl ethers (PBDEs), decabromodiphenyl ethane (DBDPE), dechlorane plus (DP), short- and medium-chain chlorinated paraffins (SCCPs, MCCPs), as well as polychlorinated biphenyls (PCBs). In ~50% of the samples chlorinated paraffins (CPs) were present in the mg/g fat range, i.e. three to four orders of magnitude higher concentrated than the sum of all other target compounds. In contrast the remaining ~50% of the samples were free of CPs, while the other HFRs were comparable in CP-positive and CP-negative samples. The exceptionally high concentrations and exclusive presence of CPs in half of the samples produced strong evidence that these compounds were released from the baking oven itself. This hypothesis was supported by detection of MCCPs at even higher concentrations in the inner components of one dismantled baking oven. The release of substantial amounts of HFRs from the oven casing during its use may contribute to human exposure to these compounds, especially MCCPs and SCCPs. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of honey supplementation combined with different jumping exercise intensities on bone mass, serum bone metabolism markers and gonadotropins in female rats

PubMed Central

2014-01-01

Background The effects of high and low jumping exercise intensities combined with honey on bone and gonadotrophins were investigated in eighty four 9 week-old female rats. Methods The experimental groups were 20 or 80 jumps per day combined with or without honey supplementation (HJ20, HJ80, J20 and J80), honey supplementation (H), sedentary without supplementation control (C), and baseline control (C0) groups. Results Study results showed that HJ80 elicited greatest beneficial effects on tibial and femoral mass, serum total calcium and alkaline phosphatase concentrations. There were significantly (p < 0.05) lower levels of serum follicle stimulating hormone concentrations in H, J20, J80 compared to C, with exception of HJ20 and HJ80. Serum luteinizing hormone concentrations were significantly (p < 0.05) greater in HJ20, HJ80 and J20 compared to J80. Conclusions It appears that high intensity jumping exercise combined with honey supplementation resulted more discernable effects on bone. Meanwhile, honey may protect against the adverse effects induced by jumping exercise on gonadotropins in female rats. PMID:24708608

The role of polyelectrolytes in the stabilization of calcium phosphate nanoparticles for the production of biomimetic materials

NASA Astrophysics Data System (ADS)

Krogstad, Daniel; Wang, Dongbo; Lin-Gibson, Sheng

2014-03-01

The exceptional mechanical properties of bone are a result of the hierarchical assembly of hydroxyapatite and the bone matrix, which is primarily composed of collagen. However, it has been shown that without highly acidic, non-collagenous proteins (NCP), which comprise only a few percent of the total organic material, collagen cannot be mineralized correctly. Although the exact roles of these NCP are unknown, it is believed that they are responsible for the stabilization and transportation of the apatite precursor, amorphous calcium phosphate (ACP). In this work, polyaspartic acid was used as a synthetic analog for NCP and the structure and kinetics of calcium phosphate nanoparticle formation were determined at various concentrations using cryo-TEM and scattering. From this investigation, it was determined that the size and stability of the ACP nanoparticles could be directly controlled by the relative ion and polymer concentrations. Interestingly, at high polymer concentrations, the particles remained suspended in solution even after they transformed from ACP to apatite indicating that the polymers have a strong ability to prevent particle aggregation. Through these results, control over the particle size and stability has been increased which will help in the design and development of biomimetic materials.

Does heavy metal exposure affect the condition of Whitethroat (Sylvia communis) nestlings?

PubMed

Turzańska-Pietras, Katarzyna; Chachulska, Justyna; Polechońska, Ludmiła; Borowiec, Marta

2018-03-01

Anthropogenic pollution results in high concentrations of heavy metals in the environment. Due to their persistence and a high potential for bioaccumulation, metals are a real threat for birds breeding in industrial areas. The aim of the present study has been to explore the contents of heavy metals (arsenic As, cadmium Cd, chromium Cr, copper Cu, iron Fe, nickel Ni, lead Pb and zinc Zn) in the excreta of Whitethroat (Sylvia communis) nestlings living in polluted environment and to investigate the relationship between these contents and the nestlings' condition. Excrement samples contained all the studied elements. The contents of arsenic, cadmium, copper and zinc in the excreta of nestlings from nests located close to a slag dump were several times higher than in the soil near the dump, which suggested accumulation in food consumed by the birds. Condition parameters (body mass and haemoglobin concentration) were not related to heavy metal concentrations in the nestlings' excreta, except of Zn. It is possible that Whitethroats are able to detoxicate heavy metals to a certain extent. Detailed, multi-element analysis of the environment, food and bird tissues or excreta should be performed to explore relations between different chemicals and bird condition.

Reconnaissance of the water resources of the Hoh Indian Reservation and the Hoh River basin, Washington

USGS Publications Warehouse

Lum, W.E.; Nelson, L.M.

1986-01-01

Ground- and surface-water resources of the Hoh Indian Reservation and the Hoh River basin were studied from 1977 to 1980 under a cooperative agreement between the U.S. Geological Survey and the Hoh Indian Tribe. It was determined that moderate quantities of groundwater can be obtained from near-surface, river-deposited sands and gravels on the northeastern part of the reservation. Groundwater recharge (induced by pumping from a nearby oxbow lake) could supply numerous wells indefinitely with yields of 25 to 50 gallons/min. Geologic units in other areas of the reservation appear to have a low hydraulic conductivity and would yield little, if any, water to wells. At seven sites where housing construction is planned, soils were tested for infiltration rates and it was determined that soils are adequate for waste disposal in septic tanks and associated drain fields at those locations. Chalaat Creek, which flows across the reservation, provides water for salmon-rearing ponds. Except for moderately high bacteria concentrations (fecal coliform bacteria concentrations were as high as 33 colonies/100 mL), results of water quality analyses indicate no unusual or harmful concentrations of any chemical constituent or physical properties of the water that would restrict its use for most purposes. Chemical and bacteriological analyses of the Hoh River and its major tributaries downstream from the Olympic Park boundary revealed no unusual or harmful levels of constituents, with some minor exceptions. Small increases in concentrations of sodium, chloride, nitrite plus nitrate, and turbidity were measured in water samples collected from the Hoh River in a downstream direction. These increases are probably the result of natural weathering of rocks and soils in the basin. Fluvial-sediment transport of the Hoh River was 82,000 tons from March 1978 to February 1979 and 1,510,000 tons from March 1979 to February 1980. Mean annual transport was estimated to be 630 ,000 tons. About 60% of the sediment transported by the Hoh River originates from within the boundaries of the Olympic National Park, which includes about 70% of the area of the Hoh River drainage basin. (USGS)

Plasma isoflavones in Malaysian men according to vegetarianism and by age.

PubMed

Hod, Rafidah; Kouidhi, Wided; Ali Mohd, Mustafa; Husain, Ruby

2016-01-01

Epidemiological studies indicate lower prevalences of breast and prostate cancers and cardiovascular disease in Southeast Asia where vegetarianism is popular and diets are traditionally high in phytoestrogens. This study assessed plasma isoflavones in vegetarian and non-vegetarian Malaysian men according to age. Daidzein, genistein, equol (a daidzein metabolite), formononetin, biochanin A, estrone, estradiol and testosterone were measured by validated liquid chromatography tandem mass spectrometry (LCMSMS). Plasma isoflavone and sex hormone concentrations were measured in 225 subjects according to age (18-34, 35-44 and 45-67 years old). In all age groups, vegetarians had a higher concentration of circulating isoflavones compared with non-vegetarians especially in the 45-67 year age group where all isoflavones except equol, were significantly higher in vegetarians compared with omnivores. By contrast, the 18-34 year group had a significantly higher concentration of daidzein in vegetarians and significantly higher testosterone and estrone concentrations compared with non-vegetarians. In this age group there were weak correlations between estrone, estradiol and testosterone with some of the isoflavones. This human study provides the first Malaysian data for the phytoestrogen status of vegetarian and nonvegetarian men.

Mercury exposure in a large subantarctic avian community.

PubMed

Carravieri, Alice; Cherel, Yves; Blévin, Pierre; Brault-Favrou, Maud; Chastel, Olivier; Bustamante, Paco

2014-07-01

Mercury (Hg) contamination poses potential threats to ecosystems worldwide. In order to study Hg bioavailability in the poorly documented southern Indian Ocean, Hg exposure was investigated in the large avian community of Kerguelen Islands. Adults of 27 species (480 individuals) showed a wide range of feather Hg concentrations, from 0.4 ± 0.1 to 16.6 ± 3.8 μg g(-1) dry weight in Wilson's storm petrels and wandering albatrosses, respectively. Hg concentrations increased roughly in the order crustacean- < fish- ≤ squid- ≤ carrion-consumers, confirming that diet, rather than taxonomy, is an important driver of avian Hg exposure. Adults presented higher Hg concentrations than chicks, due to a longer duration of exposure, with the only exception being the subantarctic skua, likely because of feeding habits' differences of the two age-classes in this species. High Hg concentrations were reported for three species of the poorly known gadfly petrels, which merit further investigation. Copyright © 2014 Elsevier Ltd. All rights reserved.

EVALUATION OF AUSTRALIAN RUM JUNGLE URANIUM CONCENTRATE FOR USE AS NLO REFINERY FEED

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

Collopy, T.J.; Huntington, C.W.; Blum, J.F.

1956-01-20

A laboratory evaluation of Australian Rum Jungle uranium concentrate showed that the uracium can be satisfactorily extracted by 33.5% TBP-kerosene from an aqueous acid slurry of the material, and that impurities in the aqueous uranyl nitrate product obtained by re-extraetion from the organic phase approach NL0 tolerance specifications. The uranium values in the organic product were not completely re-extracted at room temperatare (l0th stage organic, 1.6 g/l U); however, it was assumed that reextraction will be complete under pulse column conditions (150 deg F). The results of the Pilot Plant evaluation of Rum Jungle uranium concentrate (Lot No. 1) indicatedmore » that this material can be processed employing NLO refinery conditions. The aqueous uranyl nitrate product from the test met all impurity specifications except those for manganese and nickel. The high chloride content of this lot of concentrate will mske blending necessary in order to meet NLO feed material specifications. The blending will alan lessen the tendencies toward metallic contamination of the OK liquor observed in these tests. (auth)« less

Transformation of ATLA-negative leukocytes by blood components from anti-ATLA-positive donors in vitro.

PubMed

Miyamoto, K; Tomita, N; Ishii, A; Nishizaki, T; Kitajima, K; Tanaka, T; Nakamura, T; Watanabe, S; Oda, T

1984-06-15

Anti-ATLA-positive blood components transformed healthy human leukocytes in vitro. Blood components examined were packed red cells, whole blood, platelet concentrate and fresh frozen plasma. Leukocytes present in anti-ATLA-positive blood components such as packed red cells, whole blood and platelet concentrate easily transformed anti-ATLA-negative leukocytes. Co-culture in fresh frozen plasma, however, did not transform recipient leukocytes, and leukocytes of anti-ATLA-positive recipients proved refractory to transformation. The transformed cells were morphologically lymphoid, grew in suspension, and possessed normal recipient karyotypes except in the case of three platelet concentrates. A high proportion of all the transformed populations formed E-rosettes with neuraminidase-treated sheep erythrocytes. The cytoplasm of over 90% of each recipient was stained brilliantly with antibodies against ATLV-determined antigens. Electron microscopy of these transformed cells revealed many C-type virus particles in the extracellular space. Blood components, such as packed red cells, whole blood and platelet concentrate, containing leukocytes from anti-ATLA-positive donors, should be used cautiously to prevent the transmission on ATLV to anti-ATLA-negative recipients.

Organochlorines and selenium in California night-heron and egret eggs

USGS Publications Warehouse

Ohlendorf, Harry M.; Marois, Katherine C.

1990-01-01

Exceptionally high concentrations of DDE were found in black-crowned night-heron (Nycticorax nycticorax) (geometric mean 8.62 μg g−1 wet wt.) and great egret (Casmerodius albus) (24.0 μg g−1) eggs collected from the Imperial Valley (Salton Sea), California in 1985. DDE concentrations in 14 of the 87 (16%) randomly selected night-heron eggs from six colonies (two in San Francisco Bay, three in the San Joaquin Valley, and one at Salton Sea) were higher than those associated with reduced reproductive success of night-herons (8 μg g−1). In addition, mean shell thickness of night-heron eggs collected from the San Joaquin Valley and from San Francisco Bay during 1982–1984 was significantly less than pre-DDT thickness and was negatively correlated (r=−0.50, n=75, P<0.0001) with DDE concentration. Mean selenium concentration in night-heron eggs from Salton Sea (1.10 μg g−1) was significantly higher than in eggs from three locations in the San Joaquin Valley, and in egret eggs from Salton Sea.

In vitro activity of echinocandins against 562 clinical yeast isolates from a Romanian multicentre study.

PubMed

Mares, Mihai; Minea, Bogdan; Nastasa, Valentin; Rosca, Irina; Bostanaru, Andra-Cristina; Marincu, Iosif; Toma, Vasilica; Cristea, Violeta Corina; Murariu, Carmen; Pinteala, Mariana

2018-06-01

The study presents the echinocandin susceptibility profile of a multi-centre collection of pathogenic yeast isolates from Romanian tertiary hospitals. The 562 isolates were identified using ID32C strips, MALDI-TOF MS and DNA sequencing. Minimal inhibitory concentrations (MICs) of caspofungin (CAS), micafungin (MCA), and anidulafungin (ANI) were assessed and interpreted according to EUCAST guidelines. Minimal fungicidal concentrations (MFC) were determined by plating content from the clear MIC wells. The activity was considered fungicidal at MFC/MIC ≤ 4. The three echinocandins had strongly correlated MICs and high percentages of MIC essential agreement. Most often, MCA had the lowest MICs, followed by CAS and ANI. Against C. parapsilosis and C. kefyr, CAS had the lowest MIC values. The MIC50 values were between 0.03 and 0.25 mg/l, except C. parapsilosis. The MIC90 values were usually one dilution higher. MFCs and MICs were weakly correlated. ANI and MCA had the lowest MFC values. The MFC50 values were between 0.06 and 0.5 mg/l, except C. parapsilosis, C. guilliermondii, and C. dubliniensis. The MFC90 values were usually two dilutions higher. Based on EUCAST breakpoints, 47 isolates (8.4%) were resistant to at least one echinocandin, most often ANI. Most resistant isolates were of C. albicans, C. glabrata, and C. krusei. There were 17 isolates (3%) resistant to echinocandins and fluconazole and most belonged to the same three species. MCA and ANI had the highest rates of fungicidal activity. The high rates of echinocandin resistance and significant multidrug resistance make prophylaxis and empiric therapy difficult.

Stress induced by heavy metals on breeding of magpie (Pica pica) from central Iran.

PubMed

Zarrintab, Mohammad; Mirzaei, Rouhollah

2017-09-01

The aim of this study was to address the impacts of some heavy metals (Cd, Pb, Zn, Ni and Cu) contamination on laying behavior, egg quality and breeding performance of Pica pica in north of Isfahan Province, Iran. During the breeding season of 2013, magpie's egg content and eggshell as well as nestling excrements and feathers were collected and total concentrations of heavy metals were measured by ICP-OES. Except for Zn in nestling feathers, the significantly higher concentrations of heavy metals were observed in nestling excrements than other samples. Also, comparison of heavy metals concentrations in egg content and eggshell showed that egg content had significantly higher concentrations of Zn and Pb, instead eggshell had significantly higher amount of Cu and Cd. Except for Cu, all heavy metals concentrations in eggshell had a negative relationship with morphological characters; and also concentration of Cu in egg content showed a significantly negative correlation with egg weight and volume. The most of heavy metals in nestling feathers and excrements had strongly positive correlations with each other. Also all heavy metals levels in eggshell and egg content had significantly positive correlations (except for Cu). Unhatched eggs had significantly lower weight but also greater levels of Zn, Cd, and Pb, than randomly collected eggs. No significant differences were observed for morphometric measurements of eggs between different sites, however, a decreased gradient was observed in egg volume toward the brick kiln site. Samples collected in brick kiln site accumulated higher concentrations of heavy metals than other sites. Although numbers of clutch size in brick kiln site were significantly higher than other sites, however, other breeding variable were lower than other sites. It can be suggested that ecosystem contamination may be caused to decrease the reproduction rate of Pica pica in brick kiln, probably by laying more poor quality eggs per clutch and nestling mortality. Copyright © 2017 Elsevier Inc. All rights reserved.

Level, source identification, and risk analysis of heavy metal in surface sediments from river-lake ecosystems in the Poyang Lake, China.

PubMed

Zhang, Hua; Jiang, Yinghui; Ding, Mingjun; Xie, Zhenglei

2017-09-01

The concentrations, sources, and risks of heavy metals (Fe, Al, Mn, Cr, Co, Ni, Cu, Zn, As, Cd, W, Pb, and Tl) in sediments in five river-lake ecosystems in the Poyang Lake region were studied. The concentrations of the heavy metals varied spatially, with most of the highest concentrations in the Raohe river-lake ecosystem (RH). All heavy metals except As, Cd, W, and Tl were enriched in sediments possessing high total organic carbon contents or in finer sediments. Based on enrichment factors and statistical methods, it was found that Cd in sediments in the Xiushui (XS), Ganjiang (GJ), Xinjiang (XJ) river-lake ecosystems, and RH; Mn in the XS, GJ, and RH; and W in the XS and GJ were greatly affected by anthropogenic inputs. Moreover, the origins of Cu, Zn, and As require more attention due to the high concentrations found. The high enrichment factor of Cd in the sediments indicated that this metal might cause significant pollution in the environment. The results of the modified potential ecological risk index revealed that the XS, GJ, RH, and XJ were at considerable ecological risk, while the sediments in the Fuhe river-lake ecosystem (FH) were at moderate ecological risk, with Cd contributing the highest proportion of risk. The hazard score fundamentally validated the modified potential ecological risk analysis and revealed a mean toxicity of 57.80% to the benthic organisms in the RH.

Spatial characterization, risk assessment, and statistical source identification of the dissolved trace elements in the Ganjiang River-feeding tributary of the Poyang Lake, China.

PubMed

Zhang, Hua; Jiang, Yinghui; Wang, Min; Wang, Peng; Shi, Guangxun; Ding, Mingjun

2017-01-01

Surface water samples were collected from 20 sampling sites throughout the Ganjiang River during pre-monsoon, monsoon, and post-monsoon seasons, and the concentrations of dissolved trace elements were determined by inductively coupled plasma-mass spectrometry (ICP-MS) for the spatial and seasonal variations, risk assessment, source identification, and categorization for risk area. The result demonstrated that concentrations of the elements exhibited significant seasonality. The high total element concentrations were detected at sites close to the intensive mining and urban activities. The concentrations of the elements were under the permissible limits as prescribed by related standards with a few exceptions. The most of heavy metal pollution index (HPI) values were lower than the critical index limit, indicating the basically clean water used as habitat for aquatic life. As was identified as the priority pollutant of non-carcinogenic and carcinogenic concerns, and the inhabitants ingesting the surface water at particular site might be subjected to the integrated health risks for exposure to the mixed trace elements. Multivariate statistical analyses confirmed that Zn, As, Cd, and Tl were derived from mining and urban activities; V, Cd, and Pb exhibited mixed origin; and Co, Ni, and Cu mainly resulted from natural processes. Three categorized risk areas corresponded to high, moderate, and low risks, respectively. As a whole, the upstream of the Ganjiang River was identified as the high-risk area relatively.

The distribution and hydrogeological controls of fluoride in the groundwater of central Ethiopian rift and adjacent highlands

NASA Astrophysics Data System (ADS)

Ayenew, Tenalem

2008-05-01

Occurrence of fluoride (F) in groundwater has drawn worldwide attention, since it has considerable impact on human health. In Ethiopia high concentrations of F in groundwaters used for community water supply have resulted in extensive dental and skeletal fluorosis. As a part of a broader study, the distribution of F in groundwater has been investigated, and compared with bedrock geology and pertinent hydrochemical variables. The result indicates extreme spatial variations. High F concentration is often associated with active and sub-active regional thermal fields and acidic volcanics within high temperature rift floor. Variations in F can also be related to changes in calcium concentration resulting from dissolution of calcium minerals and mixing with waters of different chemical composition originated from variable hydrogeological environment across the rift valley. The concentration of F dramatically declines from the rift towards the highlands with the exception of scattered points associated with thermal springs confined in local volcanic centers. There are also interactions of F-rich alkaline lakes and the surrounding groundwater. Meteoric waters recharging volcanic aquifers become enriched with respect to F along the groundwater flow path from highland recharge areas to rift discharge areas. Locally wells drilled along large rift faults acting as conduits of fresh highland waters show relatively lower F. These areas are likely to be possible sources of better quality waters within the rift. The result of this study has important implications on site selection for water well drilling.

High Pb/Ce reservoir in depleted, altered mantle peridotites

NASA Astrophysics Data System (ADS)

Godard, M.; Kelemen, P.; Hart, S.; Jackson, M.; Hanghoj, K.

2005-12-01

We find consistent, high Pb/Ce in ICP-MS data for residual peridotites from the Mid-Atlantic Ridge (MAR, from ODP Leg 209), mid-ocean ridges (MOR) worldwide [1], Oman, Josephine and Trinity ophiolites, and the Jurassic Talkeetna arc. (MAR and Oman data from Montpellier; Josephine, Trinity and Talkeetna from WSU; some Pb concentrations checked by ID at WHOI). These samples have average Pb/Ce 10x primitive mantle (PM), with only 3 of 180 samples < PM. REE patterns and Ce concentration < PM in 165 of 180 samples are consistent with depletion via melt extraction, plus some magmatic refertilization. High Pb (average 3x PM, median 0.5x PM), could be due to (a) retention of Pb in residual sulfide, (b) addition of Pb in sulfide and plagioclase during `impregnation' by crystallizing melt, and/or (c) addition of Pb in sulfide and carbonate during alteration. Pb/Ce is correlated negatively with Ce concentration, suggesting a role for (a). Pb concentration is strongly correlated with Th and Nb. These elements are considered immobile during hydrothermal alteration, their correlations with Pb are positive, and Pb is > PM in many samples, all suggesting a complementary role for (b) and a limited role for (c). All samples except Talkeetna have Th/Pb < PM. All samples except some MOR peridotites also have U/Pb < PM. DRILLED MAR peridotites show U/Pb > PM in shallow, oxidized samples and < PM in downhole, reduced samples. Thus, high U/Pb in DREDGED MOR peridotites [1] is attributed to seafloor weathering. Given that oxidized weathering only extends tens of meters below the seafloor, we infer that most MOR peridotites have Th/Pb and U/Pb < PM. If they form with Pb isotope ratios similar to MORB, these rocks will evolve to values less radiogenic than the geochron. The effect of subduction modification on Th/Pb and U/Pb is unclear. For example, if elevated Pb is common in unaltered residual peridotites, subduction modification is likely to be minor. The size of the high Pb/Ce, low Th/Pb and U/Pb reservoir represented by these rocks depends on the reason for elevated Pb. We discuss three possibilities as outlined above. (a) Pb enrichment is most marked in highly depleted residues, abundant in the upper 30 km of the oceanic mantle. (b) Crystallization of igneous sulfide and plagioclase from cooling melt migrating along peridotite grain boundaries may be common in the upper 20 km in plates formed at slow spreading ridges. (c) Hydrothermal alteration of shallow mantle peridotite at slow spreading ridges might extend to 10 km. Based on these estimates, over geologic time tens of percent of mantle Pb could be sequestered in such a reservoir. This offers a potential solution to the "first lead paradox". [1] Niu, J. Petrol. 2004

Sodium and chloride levels in rainfall, mist. streamwater and groundwater at the Plynlimon catchments, mid-Wales: inferences on hydrological and chemical controls

NASA Astrophysics Data System (ADS)

Neal, C.; Kirchner, J. W.

Variations in sodium and chloride in atmospheric inputs (rainfall and mist), stream runoff and groundwater stores are documented for the upper Severn River (Afon Hafren and Afon Hore catchments), Plynlimon, mid-Wales. The results show five salient features.

1. Sodium and chloride concentrations are highly variable and highly correlated in rainfall and mist. The sodium-chloride relationship in rainfall has a slope close to the sodium/chloride ratio in sea-water, and an intercept that is not significantly different from zero. This indicates that sea-salt is the dominant source of both sodium and chloride in rainfall, which would be expected given the maritime nature of the metrology. For mist, there is also a straight line with near-zero intercept, but with a slightly higher gradient than the sea-salt ratio, presumably due to small additional sodium inputs from other sources.
2. There is an approximate input-output balance for both sodium and chloride, with the exception of one groundwater well, in which high chemical weathering results in an anomalous high Na/Cl ratio. Thus, atmospheric deposition is the dominant source of both sodium and chloride in groundwater and streamflow.
3. The fluctuations in sodium and chloride concentrations in the streams and groundwaters are strongly damped compared to those in the rain and the mist, reflecting the storage and mixing of waters in the subsurface.
4. On all timescales, from weeks to years, sodium fluctuations are more strongly damped than chloride fluctuations in streamflow. The additional damping of sodium is consistent with ion exchange buffering of sodium in the catchment soils.
5. Sodium and chloride concentrations are linearly correlated in the streams and groundwaters, but the slope is almost universally less than the sea-salt ratio and there is a non-zero intercept. The Na/Cl ratio in streamflow and groundwater is higher than the sea-salt ratio when salinity is low and lower than the sea-salt ratio when salinity is high. This pattern of behaviour is again consistent with ion exchange buffering of sodium in the catchment soils.

Effects of heavy metal pollution in the Pilcomayo river system Bolivia, on resident human populations

NASA Astrophysics Data System (ADS)

Hudson-Edwards, K. A.; Miller, J. R.; Presto, D.; Lechler, P. J.; Macklin, M. G.; Miners, J. S.; Turner, J. N.

2003-05-01

The Pilcomayo river in Bolivia drains the Potosi mining district and flows downstream, exposing indigenous populations, who rely on the river for drinking water, irrigation and fish, to elevated levels of toxic metals. A preliminary analysis of agricultural soil and crops from four riverside Pilcomayo communities has shown that many agricultural fields are contaminated with heavy metals (Ag, Cd, Cu, Pb, Sb, Zn) and arsenic(As) However, concentrations of these elements in most crops are within guideline values. Concentrations of metals and As in samples of drinking water are, for the most part, lower than concentrations in Pilcomayo river water taken at the respective communities, and the drinking water concentrations are within guideline values. Exceptions are Sb and As concentrations in two of the communities. In irrigation waters, Zn and Pb exceed recommended guideline values in two of the communities, and may lead to highZn and Pb values in some crops and soils. The work carried out to date suggests that the strategies used by these communities appear to considerably reduce their risks to exposure. Work is ongoing to develop more complex and effective strategies based on further geochemical analyses and social science surveys.

Elemental distribution in seaweed, Gelidium abbottiorum along the KwaZulu-Natal Coastline, South Africa.

PubMed

Misheer, Natasha; Kindness, Andrew; Jonnalagadda, Sreekanth B

2006-01-01

The total concentrations of 7 selected metals, namely manganese, iron, zinc, titanium, boron, arsenic and mercury, were monitored for one annual cycle covering four seasons in the seaweed, Gelidium abbottiorum, at four sampling sites at Zinkwasi, Ballito, Treasure beach and Park Rynie along the South-East coastline of KwaZulu-Natal, South Africa to assess the current status of the marine environment. Inductively Coupled Plasma Optical Emission Spectrophotometry, Mercury Cold Vapour AAS, and Hydride Generation AAS were used for the determination of metal concentrations. Mn concentrations were particularly high in the G. abbottiorum species, followed by Fe, As and B concentrations which were in the 3-8 ppm range. Ti and Zn were in the 100-400 ppb range, while Hg was low and below 100 ppb. A typical sample of G. abbottiorum at Treasure beach, a site close to Durban metropolis in winter had Mn (8.6 ppm), Fe (4.6 ppm), As (5.6 ppm), B (3.0 ppm), Ti (420 ppb), Zn (167 ppb) and Hg (7.5 ppb). All metals recorded a decrease in concentrations from winter to spring with the exception of Hg. The Hg levels increased considerably from winter to spring.

Distribution and bioaccumulation of endocrine disrupting chemicals in water, sediment and fishes in a shallow Chinese freshwater lake: Implications for ecological and human health risks.

PubMed

Dan Liu; Wu, Shengmin; Xu, Huaizhou; Zhang, Qin; Zhang, Shenghu; Shi, Lili; Yao, Cheng; Liu, Yanhua; Cheng, Jie

2017-06-01

The occurrence, distribution and bioaccumulation of six endocrine disrupting compounds (EDCs) were investigated in water, sediment and biota samples from Luoma Lake, a shallow Chinese freshwater lake. Total concentrations of ∑phenolic EDCs were much higher than ∑estrogens EDCs in both waters and sediments. There were not obvious differences on the concentrations of target compounds [except nonylphenol (NP)] in upstream, lake and downstream locations, these may be suggested that they were mainly affected by non-point discharges in this area. However, the high concentration of NP in water may be associated with the discharge of rural domestic wastewater without thorough treatment. Furthermore, concentrations of NP were about 2-3 order magnitude higher than those of OP in both water and sediment compartments. Relatively higher bioaccumulation factors (BAF) were obtained for DES and EE2. Ecological risk assessment revealed greater risk of NP in surface water, which may pose a serious threat to aquatic ecosystems. The estrogen equivalent concentration (EEQ) of male were higher than those in female, and occurred in the order of city >rural-urban>countryside. Copyright © 2017 Elsevier Inc. All rights reserved.

Human Development Inequality Index and Cancer Pattern: a Global Distributive Study.

PubMed

Rezaeian, Shahab; Khazaei, Salman; Khazaei, Somayeh; Mansori, Kamyar; Sanjari Moghaddam, Ali; Ayubi, Erfan

2016-01-01

This study aimed to quantify associations of the human development inequality (HDI) index with incidence, mortality, and mortality to incidence ratios for eight common cancers among different countries. In this ecological study, data about incidence and mortality rates of cancers was obtained from the Global Cancer Project for 169 countries. HDI indices for the same countries was obtained from the United Nations Development Program (UNDP) database. The concentration index was defined as the covariance between cumulative percentage of cancer indicators (incidence, mortality and mortality to incidence ratio) and the cumulative percentage of economic indicators (country economic rank). Results indicated that incidences of cancers of liver, cervix and esophagus were mainly concentrated in countries with a low HDI index while cancers of lung, breast, colorectum, prostate and stomach were concentrated mainly in countries with a high HDI index. The same pattern was observed for mortality from cancer except for prostate cancer that was more concentrated in countries with a low HDI index. Higher MIRs for all cancers were more concentrated in countries with a low HDI index. It was concluded that patterns of cancer occurrence correlate with care disparities at the country level.

Assessment of allelopathic properties of Aloe ferox Mill. on turnip, beetroot and carrot.

PubMed

Arowosegbe, Sunday; Afolayan, Anthony J

2012-01-01

Turnip (Brassica rapa var. rapa L.), beetroot (Beta vulgaris L.) and carrot (Daucus carota L.) are common vegetables in South Africa. The allelopathic potential of aqueous leaf and root extracts of Aloe ferox Mill.- a highly valued medicinal plant- was evaluated against seed germination and seedling growth of the three vegetables in Petri dish experiments. The extracts were tested at concentrations of 2, 4, 6, 8, and 10 mg/mL. Leaf extract concentrations above 4 mg/mL inhibited the germination of all the crops, while the root extract had no significant effect on germination irrespective of concentration. Interestingly, the lowest concentration of leaf extract stimulated root length elongation of beetroot by 31.71%. Other concentrations significantly inhibited both root and shoot growth of the vegetable crops except the turnip shoot. The most sensitive crop was carrot, with percentage inhibition ranging from 29.15 to 100% for root and shoot lengths. Lower percentage inhibition was observed for the root extract than the leaf extract against shoot growth of beetroot and carrot. The results from this study suggested the presence of allelochemicals mostly in the leaves of A. ferox that could inhibit the growth of the turnip, beetroot and carrot.

Molybdenum Availability Is Key to Nitrate Removal in Contaminated Groundwater Environments

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

Thorgersen, Michael P.; Lancaster, W. Andrew; Vaccaro, Brian J.

2015-05-15

The concentrations of molybdenum (Mo) and 25 other metals were measured in groundwater samples from 80 wells on the Oak Ridge Reservation (ORR) (Oak Ridge, TN), many of which are contaminated with nitrate, as well as uranium and various other metals. Moreover, the concentrations of nitrate and uranium were in the ranges of 0.1 μM to 230 mM and <0.2 nM to 580 μM, respectively. Most metals examined had significantly greater median concentrations in a subset of wells that were highly contaminated with uranium (≥126 nM). They included cadmium, manganese, and cobalt, which were 1,300- to 2,700-fold higher. A notablemore » exception, however, was Mo, which had a lower median concentration in the uranium-contaminated wells. This is significant, because Mo is essential in the dissimilatory nitrate reduction branch of the global nitrogen cycle. It is required at the catalytic site of nitrate reductase, the enzyme that reduces nitrate to nitrite. Furthermore, more than 85% of the groundwater samples contained less than 10 nM Mo, whereas concentrations of 10 to 100 nM Mo were required for efficient growth by nitrate reduction for twoPseudomonasstrains isolated from ORR wells and by a model denitrifier,Pseudomonas stutzeriRCH2. Higher concentrations of Mo tended to inhibit the growth of these strains due to the accumulation of toxic concentrations of nitrite, and this effect was exacerbated at high nitrate concentrations. The relevance of these results to a Mo-based nitrate removal strategy and the potential community-driving role that Mo plays in contaminated environments are discussed.« less

Particulate concentrations during on-farm combustion of energy crops of different shapes and harvest seasons

NASA Astrophysics Data System (ADS)

Fournel, S.; Palacios, J. H.; Morissette, R.; Villeneuve, J.; Godbout, S.; Heitz, M.; Savoie, P.

2015-03-01

The increasing energy costs and environmental concerns of farms have motivated the growing interest of agricultural producers in using farm-grown biomass as a substitute to fossil fuels for heat production. However, the use of non-woody biomass is facing challenges due to variability regarding chemical composition and fuel properties that may induce problems during combustion such as particulate matter (PM). The aim of this work was to measure and compare total PM concentrations during on-farm combustion of wood and four agricultural crops: short-rotation willow, switchgrass, miscanthus and reed canary grass. In order to study the influence of physicochemical properties, different shapes (pellets, chips and chopped grasses) and harvest seasons (fall and spring) were also evaluated. In this context, a representative small-scale (29 kW), multi-fuel boiler for light commercial use was utilized. The boiler was also non-catalytic so that the burning took place in a single combustion chamber. Overall, twelve different biomass fuels were tested and each product was burned three times. Mean PM concentration of wood (416 mg Nm-3 at 7 vol% O2) was lower than that of the four dedicated energy crops (505-1417 mg Nm-3 at 7 vol% O2). However, because of the high variability between the experiments, no statistical significance was observed at P > 0.1 level except in one case. The PM amounts were high compared to literature data and Quebec's environmental regulation mainly because of the boiler system used. Except for willow, pelletized products decreased PM levels by 22-52% compared to chopped materials. Bulky biomass of low density was unable to reach steady-state conditions and produced compounds associated with incomplete combustion including PM. Spring-harvested biomass fuels showed a PM reduction up to 48% compared to fall-harvested crops. This was likely due to a 20-60% decrease of several chemical elements in the biomass, namely S, Cl, K and P which are the main constituents of fly ash.

Identifying sources of ozone to three rural locations in Nevada, USA, using ancillary gas pollutants, aerosol chemistry, and mercury.

PubMed

Miller, Matthieu B; Fine, Rebekka; Pierce, Ashley M; Gustin, Mae S

2015-10-15

Ozone (O3) is a secondary air pollutant of long standing and increasing concern for environmental and human health, and as such, the US Environmental Protection Agency will revise the National Ambient Air Quality Standard of 75 ppbv to ≤ 70 ppbv. Long term measurements at the Great Basin National Park (GBNP) indicate that O3 in remote areas of Nevada will exceed a revised standard. As part of the Nevada Rural Ozone Initiative, measurements of O3 and other air pollutants were made at 3 remote sites between February 2012 and March 2014, GBNP, Paradise Valley (PAVA), and Echo Peak (ECHO). Exceptionally high concentrations of each air pollutant were defined relative to each site as mixing ratios that exceeded the 90th percentile of all hourly data. Case studies were analyzed for all periods during which mean daily O3 exceeded the 90th percentile concurrently with a maximum 8-h average (MDA8) O3 that was "exceptionally high" for the site (65 ppbv at PAVA, 70 ppbv at ECHO and GBNP), and of potential regulatory significance. An MDA8 ≥ 65 ppbv occurred only five times at PAVA, whereas this occurred on 49 and 65 days at GBNP and ECHO, respectively. The overall correlation between O3 and other pollutants was poor, consistent with the large distance from significant primary emission sources. Mean CO at these locations exceeded concentrations reported for background sites in 2000. Trajectory residence time calculations and air pollutant concentrations indicate that exceedances at GBNP and ECHO were promoted by air masses originating from multiple sources, including wildfires, transport of pollution from southern California and the marine boundary layer, and transport of Asian pollution plumes. Results indicate that the State of Nevada will exceed a revised O3 standard due to sources that are beyond their control. Copyright © 2015 Elsevier B.V. All rights reserved.

Distribution of heavy metals in muscles and internal organs of Korean cephalopods and crustaceans: risk assessment for human health.

PubMed

Mok, Jong Soo; Kwon, Ji Young; Son, Kwang Tae; Choi, Woo Seok; Shim, Kil Bo; Lee, Tae Seek; Kim, Ji Hoe

2014-12-01

Samples of seven species of cephalopods and crustaceans were collected from major fish markets on the Korean coast and analyzed for mercury (Hg) using a direct Hg analyzer and for the metals cadmium (Cd), lead (Pb), chromium, silver, nickel, copper, and zinc using inductively coupled plasma mass spectrometry. The distributions of heavy metals in muscles, internal organs, and whole tissues were determined, and a risk assessment was conducted to provide information concerning consumer safety. The heavy metals accumulated to higher levels (P < 0.05) in internal organs than in muscles for all species. The mean concentrations of Cd, which had the highest concentrations of the three hazardous metals (Cd, Pb, and Hg), in all internal organs (except those of blue crab) exceeded the regulatory limits set by Korea and the European Union. The Cd concentrations in all whole tissues of squid and octopus (relatively large cephalopods), red snow crab, and snow crab exceeded the European Union limits. The estimated dietary intake of Cd, Pb, and Hg for each part of all species accounted for 1.73 to 130.57%, 0.03 to 0.39%, and 0.93 to 1.67%, respectively, of the provisional tolerable daily intake adopted by the Joint Food and Agriculture Organization and World Health Organization Expert Committee on Food Additives; the highest values were found in internal organs. The hazard index (HI) is recognized as a reasonable parameter for assessing the risk of heavy metal consumption associated with contaminated food. Because of the high HI (>1.0) of the internal organs of cephalopods and the maximum HI for whole tissue of 0.424, consumers eating internal organs or whole tissues of cephalopods could be at risk of high heavy metal exposure. Therefore, the internal organs of relatively large cephalopods and crabs (except blue crab) are unfit for consumption. However, consumption of flesh after removing internal organs is a suitable approach for decreasing exposure to harmful metals.

Electrocoagulation and nanofiltration integrated process application in purification of bilge water using response surface methodology.

PubMed

Akarsu, Ceyhun; Ozay, Yasin; Dizge, Nadir; Elif Gulsen, H; Ates, Hasan; Gozmen, Belgin; Turabik, Meral

Marine pollution has been considered an increasing problem because of the increase in sea transportation day by day. Therefore, a large volume of bilge water which contains petroleum, oil and hydrocarbons in high concentrations is generated from all types of ships. In this study, treatment of bilge water by electrocoagulation/electroflotation and nanofiltration integrated process is investigated as a function of voltage, time, and initial pH with aluminum electrode as both anode and cathode. Moreover, a commercial NF270 flat-sheet membrane was also used for further purification. Box-Behnken design combined with response surface methodology was used to study the response pattern and determine the optimum conditions for maximum chemical oxygen demand (COD) removal and minimum metal ion contents of bilge water. Three independent variables, namely voltage (5-15 V), initial pH (4.5-8.0) and time (30-90 min) were transformed to coded values. The COD removal percent, UV absorbance at 254 nm, pH value (after treatment), and concentration of metal ions (Ti, As, Cu, Cr, Zn, Sr, Mo) were obtained as responses. Analysis of variance results showed that all the models were significant except for Zn (P > 0.05), because the calculated F values for these models were less than the critical F value for the considered probability (P = 0.05). The obtained R(2) and Radj(2) values signified the correlation between the experimental data and predicted responses: except for the model of Zn concentration after treatment, the high R(2) values showed the goodness of fit of the model. While the increase in the applied voltage showed negative effects, the increases in time and pH showed a positive effect on COD removal efficiency; also the most effective linear term was found as time. A positive sign of the interactive coefficients of the voltage-time and pH-time systems indicated synergistic effect on COD removal efficiency, whereas interaction between voltage and pH showed an antagonistic effect.

40 CFR 50.14 - Treatment of air quality monitoring data influenced by exceptional events.

Code of Federal Regulations, 2011 CFR

2011-07-01

... EPA's satisfaction that emissions from fireworks displays caused a specific air pollution... to EPA's satisfaction that such event caused a specific air pollution concentration at a particular... pollution concentration in excess of one or more national ambient air quality standards at a particular air...

40 CFR 63.1253 - Standards: Storage tanks.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Standards for Pharmaceuticals Production § 63.1253 Standards: Storage tanks. (a) Except as provided in... control device achieving an outlet TOC concentration, as calibrated on methane or the predominant HAP, of... outlet TOC concentration, as calibrated on methane or the predominant HAP, of 50 ppmv or less, and an...

40 CFR 63.1253 - Standards: Storage tanks.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Standards for Pharmaceuticals Production § 63.1253 Standards: Storage tanks. (a) Except as provided in... control device achieving an outlet TOC concentration, as calibrated on methane or the predominant HAP, of... outlet TOC concentration, as calibrated on methane or the predominant HAP, of 50 ppmv or less, and an...

7 CFR 51.1911 - Damaged.

Code of Federal Regulations, 2012 CFR

2012-01-01

... stem to the blossom end. (c) Catfaces. These are irregular, dark, leathery scars at the blossom end of...) Growth cracks. These are ruptures or cracks radiating from the stem scar, or concentric to the stem scar... margin of the stem scar; except that very narrow, well healed cracks concentric to the stem scar shall...

7 CFR 51.1911 - Damaged.

Code of Federal Regulations, 2011 CFR

2011-01-01

... stem to the blossom end. (c) Catfaces. These are irregular, dark, leathery scars at the blossom end of...) Growth cracks. These are ruptures or cracks radiating from the stem scar, or concentric to the stem scar... margin of the stem scar; except that very narrow, well healed cracks concentric to the stem scar shall...

Why Do Tropical Mountains Support Exceptionally High Biodiversity? The Eastern Arc Mountains and the Drivers of Saintpaulia Diversity

PubMed Central

Dimitrov, Dimitar; Nogués-Bravo, David; Scharff, Nikolaj

2012-01-01

We combine information about the evolutionary history and distributional patterns of the genus Saintpaulia H. Wendl. (Gesneriaceae; ‘African violets’) to elucidate the factors and processes behind the accumulation of species in tropical montane areas of high biodiversity concentration. We find that high levels of biodiversity in the Eastern Arc Mountains are the result of pre-Quaternary speciation processes and environmental stability. Our results support the hypothesis that climatically stable mountaintops may have acted as climatic refugia for lowland lineages during the Pleistocene by preventing extinctions. In addition, we found evidence for the existence of lowland micro-refugia during the Pleistocene, which may explain the high species diversity of East African coastal forests. We discuss the conservation implications of the results in the context of future climate change. PMID:23185283

A preliminary investigation on the distribution of cannabinoids in man.

PubMed

Gronewold, Antonia; Skopp, Gisela

2011-07-15

An LC/MS/MS procedure to determine THC along with its major metabolites 11-OH-THC, THC-COOH and its glucuronide as well as the cannabinoids CBD and CBN was applied to 5 post mortem cases to study their distribution into some less commonly studied matrices. Analytes were determined in fluids and tissue homogenates following protein precipitation and liquid-liquid extraction. Gall bladder fluid exhibited maximum concentrations of all analytes except THC, which was detectable in high concentrations in muscle tissue along with CBD. THC was also present in lung specimens, whereas its concentration in liver samples was low or not detectable at all. Liver und kidney specimens contained appreciable amounts of THC-COOglu. Findings from bile support extensive enterohepatic recirculation of the glucuronide. Muscle tissue seems an interesting specimen to detect multiple cannabis use, and brain may serve as an alternative specimen for blood; nevertheless, the present findings should be substantiated by further investigations. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Tissue distribution and fate of persistent organic pollutants in Indo-Pacific humpback dolphins from the Pearl River Estuary, China.

PubMed

Gui, Duan; Yu, Riqing; He, Xuan; Tu, Qin; Wu, Yuping

2014-09-15

Eleven persistent organic pollutant (POP) compounds including ∑PCBs, ∑DDTs, ∑HCHs, aldrin, mirex, endrin, ∑CHLs, dieldrin, HCB, heptachlor and pentachlorobenzene were measured in the kidney, liver, muscle, melon and other tissues of Sousa chinensis stranded on the western coast of the Pearl River Estuary in China during 2007-2013. For most parameters of POPs measured, melon tissues contained the highest mean concentrations with the exception of aldrin, which was higher in the kidney and liver tissues. The concentrations of PCBs, DDTs, heptachlor and endrin in the melon tissue exhibited significant correlations with body length, whereas PCBs and heptachlor also displayed significant regression with age. Our studies showed hepatic concentrations of ∑DDTs, ∑HCHs and mirex in S. chinensis were generally higher than those found in cetaceans from other geographic locations. The high levels of POP residues in the testis of one male dolphin suggested an increasing risk of infertility in the species. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of thiomolybdate and ammonium molybdate in pregnant guinea pigs and their offspring.

PubMed

Howell, J M; Shunxiang, Y; Gawthorne, J M

1993-09-01

Groups of eight guinea pigs and their offspring were given drinking water containing molybdenum as ammonium molybdate (AM) or thiomolybdate (TM) throughout and subsequent to pregnancy. All adult females had oestrous cycles and conception rates were unaffected. Fetal death was common in groups given the high dose of TM. The concentration of copper in liver was reduced in all groups at all ages except for pups killed at birth from animals given AM. The concentration of molybdenum was elevated in liver and kidney of all groups and was statistically significant in the majority. The concentration in plasma of copper, molybdenum and copper insoluble in trichloroacetic acid was elevated in all groups. Superoxide dismutase activity was significantly reduced in dams and six-week-old pups in which TM administration commenced before mating. Histological damage occurred in the pancreas of animals given AM or TM. The effects on the fetus and pancreas were considered to result from copper deficiency rather than molybdenum toxicity.

Energy balance in adrenalectomized ob/ob mice: effects of dietary starch and glucose.

PubMed

Warwick, B P; Romsos, D R

1988-07-01

Effects of different carbohydrate types on energy balance, fatty acid synthesis, and plasma insulin concentrations in adrenalectomized ob/ob mice were investigated. Obese (ob/ob) and lean mice adrenalectomized at 4 wk of age received one of four high-carbohydrate powdered diets for 3 wk: stock, glucose, starch, or starch plus wheat bran. Adrenalectomy reduced energy intake of ob/ob mice equally independent of diet type, whereas energetic efficiency, in vivo rates of fatty acid synthesis in liver and white adipose tissue, and plasma insulin concentrations were substantially reduced to approach values in lean mice in all adrenalectomized ob/ob mice except those fed glucose. The ability of adrenalectomy to normalize energy balance in ob/ob mice depends on factors other than the reduced circulating concentration of glucocorticoids alone. Diet composition is a crucial factor, and striking differences exist between semipurified diets containing a simple sugar (glucose) and those containing a complex carbohydrate (starch), with no additional effect of dietary fiber (wheat bran).

A baseline record of trace elements concentration along the beach placer mining areas of Kanyakumari coast, South India.

PubMed

Simon Peter, T; Chandrasekar, N; John Wilson, J S; Selvakumar, S; Krishnakumar, S; Magesh, N S

2017-06-15

Trace element concentration in the beach placer mining areas of Kanyakumari coast, South India was assessed. Sewage and contaminated sediments from mining sites has contaminated the surface sediments. Enrichment factor indicates moderately severe enrichment for Pb, minor enrichment for Mn, Zn, Ni, Fe and no enrichment for Cr and Cu. The Igeo values show higher concentration of Pb ranging in the scale of 3-4, which shows strong contamination due to high anthropogenic activity such as mining and terrestrial influences into the coastal regions. Correlation coefficient shows that most of the elements are associated with each other except Ni and Pb. Factor analysis reveals that Mn, Zn, Fe, Cr, Pb and Cu are having a significant loading and it indicates that these elements are mainly derived from similar origin. The cluster analysis clearly indicated that the mining areas are grouped under cluster 2 and non-mining areas are clustered under group 1. Copyright © 2017 Elsevier Ltd. All rights reserved.

Respiratory response of guinea pigs to sulfuric acid mist

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

Amdur, M.O.

1958-01-01

Guinea pigs were exposed to 23 to 42 mg/m/sup 3/ acid mist with a mass median diameter of 0.8, 2.5, or 7 ..mu..m for 1-h periods. Significant increase in resistance at all levels and sizes was observed. There was a concurrent decrease in compliance for 2.5- and 7-..mu..m sizes with exception of lowest level of exposure. Dose-effect with resistance vs concentration shows smaller sizes were more deleterious. The 2.5 ..mu..m were more harmful at higher concentrations (above approx. 15 mg/m/sup 3/). The 0.8-..mu..m particles produced a rapid response suggesting bronchoconstriction as the mechanism (change in resistance proportionately greater than changemore » in compliance). This was similar to irritant gases. Conversely, 2.5- and 7-..mu..m particles acted slower and change in resistance paralleled the drop in compliance. High concentrations evoked edema and atelectasis. This was interpreted as closure of main bronchi rather than general constriction. Response was consistent with expected penetration.« less

Chemometric studies of water quality parameters of Sankarankovil block of Tirunelveli, Tamilnadu.

PubMed

Alagumuthu, G; Rajan, M

2010-09-01

The fluoride concentration in ground water was determined in Sankarankovil block of Tirunelveli district of Tamilnadu (India) where it is the only source of drinking water. Various other water quality parameters such as pH, electrical conductivity total hardness and total alkalinity as well as calcium, magnesium, carbonate, bicarbonate and chloride concentrations were also measured. A systematic calculation of correlation coefficient among different physico-chemical parameters was performed. The analytical results indicated considerable variations among the analyzed samples with respect to their chemical composition. Majority of the samples do not comply with Indian as well as WHO water quality standards. The fluoride concentration in the ground water of these villages varied from 0.66 to 3.84 mg l(-1), causes dental fluorosis among people especially children of these villages. The high and low fluoride containing areas were located using isopleth mapping technique. Overall water quality was found unsatisfactory for drinking purposes without any prior treatment except at few locations out of 50 villages.

The Liege-balloon program. [balloon-borne instruments for high-spectral resolution observations of the sun

NASA Technical Reports Server (NTRS)

Zander, R.

1974-01-01

The Liege-balloon program is intended to make high-spectral resolution observations of the sun in the near- and intermediate infrared regions not accessible from the ground. A description of the equipment, followed by a summary of the data obtained till now is presented. Except for ozone whose maximum of concentration lies near 25 Km altitude, the residual mass distribution of the other mentioned molecules decreases with altitude. This is a self-explanatory argument for carrying out spectroscopic observations from platforms transcending the densest layers of the earth's atmosphere. The Liege balloon equipment is primarily intended for very high-resolution solar observations from about 27-30 Km altitude, in all spectral regions between 1.5 and 15.0 microns, not accessible from the ground.

Occurrence of 25 pharmaceuticals in Taihu Lake and their removal from two urban drinking water treatment plants and a constructed wetland.

PubMed

Hu, Xia-Lin; Bao, Yi-Fan; Hu, Jun-Jian; Liu, You-Yu; Yin, Da-Qiang

2017-06-01

Pharmaceuticals in drinking water sources have raised significant concerns due to their persistent input and potential human health risks. The seasonal occurrence of 25 pharmaceuticals including 23 antibiotics, paracetamol (PAR), and carbamazepine (CMZ) in Taihu Lake was investigated; meanwhile, the distribution and removal of these pharmaceuticals in two drinking water treatment plants (DWTPs) and a constructed wetland were evaluated. A high detection frequency (>70%) in the Taihu Lake was observed for nearly all the 25 pharmaceutics. Chlortetracycline (234.7 ng L -1 ), chloramphenicol (27.1 ng L -1 ), erythromycin (72.6 ng L -1 ), PAR (71.7 ng L -1 ), and CMZP (23.6 ng L -1 ) are compounds with both a high detection frequency (100%) and the highest concentrations, suggesting their wide use in the Taihu Basin. Higher concentrations of chloramphenicols, macrolides, PAR, and CMZP were observed in dry season than in wet season, probably due to the low flow conditions of the lake in winter and the properties of pharmaceuticals. The overall contamination levels of antibiotic pharmaceutics (0.2-74.9 ng L -1 ) in the Taihu Lake were lower than or comparable to those reported worldwide. However, for nonantibiotic pharmaceutics, PAR (45.0 ng L -1 ) and CMZP (14.5 ng L -1 ), significantly higher concentrations were observed in the Taihu Lake than at a global scale. High detection frequencies of 25 pharmaceuticals were observed in both the two DWTPs (100%) and the wetland (>60%) except for florfenicol and sulfapyridine. The removal efficacies of the studied pharmaceuticals in DWTP B with advanced treatment processes including ozonation and granular activated carbon filtration (16.7-100%) were superior to DWTP A with conventional treatment processes (2.9-100%), except for sulfonamides. Wetland C with the constructed root channel technology was efficient (24.2-100%) for removing most pharmaceuticals. This work suggests that the application of cost-effective technologies such as constructed wetlands should be considered as an efficient alternative for removing pharmaceuticals from water supply sources.

Spatial variability of heavy metals in the coastal soils under long-term reclamation

NASA Astrophysics Data System (ADS)

Wang, Lin; Coles, Neil A.; Wu, Chunfa; Wu, Jiaping

2014-12-01

The coastal plain of Cixi City, China, has experienced over 1000 years of reclamation. With the rapid development of agriculture and industry after reclamation, successive inputs into agricultural soils have drastically modified the soil environment. To determine the spatial distribution of heavy metals and to evaluate the influence of anthropogenic activities, a total of 329 top soil samples were taken along a transect on the coastal plain. The samples collected across 11 sea dikes, were selected by a nested sampling methodology. Total Cu, Fe, Mn, Ni, Pb, and Zn concentrations, as well as their diethylenetriamine penta-acetic acid (DTPA) extractable (available) concentrations were determined. Results indicated that except for Zn concentrations, there was neither heavy metals pollution nor mineral deficiency in the soils. Heavy metals exhibited considerable spatial variability, obvious spatial dependence, and close relationships on the reclaimed land. For most metals, the reclamation history was the main influencing factor. Metals concentrations generally showed discontinuities around the position of sea dikes, and the longer reclamation histories tended to have higher metals concentrations than the recently reclaimed sectors. As for Cu and Zn total concentrations, stochastic factors, like industrial waste discharge, fertilization and pesticide application, probably led to the high nugget effect and altered this relationship. The 6th and 10th zones generally had the highest total metals concentrations, due to the concentration of household appliance manufacturers in these reclaimed areas. The first two zones were characterized by high available metals concentrations, probably due to the alternant flooding and emergence, low pH values and high organic matter contents in these paddy field soils. From the 3rd to 7th zones with the same land use history and soil type, metals concentrations, especially available concentrations, showed homogeneity. The nested sampling method adopted demonstrated that the 500-m interval was enough to capture the spatial variation of the metals. These results were useful in evaluating the variation in the environment quality of the soils under long-term reclamation and to formulate plans for future reclamation projects.

Exceptional damage-tolerance of a medium-entropy alloy CrCoNi at cryogenic temperatures

DOE PAGES

Gludovatz, Bernd; Hohenwarter, Anton; Thurston, Keli V. S.; ...

2016-02-02

The high-entropy alloys are an intriguing new class of metallic materials that derive their properties not from a single dominant constituent, such as iron in steels, nor from the presence of a second phase, such as in nickel-base superalloys, but rather comprise multi-element systems that crystallize as a single phase, despite containing high concentrations (~20 at.%) of five or more elements with different crystal structures. Indeed, we have recently reported on one such single-phase high-entropy alloy, NiCoCrFeMn, which displays exceptional strength and toughness at cryogenic temperatures. Here which displays unprecedented strength-toughness properties that exceed those of all high-entropy alloys andmore » most multi-phase alloys. With roomtemperature tensile strengths of almost 1 GPa and KJIc fracture-toughness values above 200 MPa.m 1/2 (with crack-growth toughnesses exceeding 300 MPa.m 1/2), the strength, ductility and toughness of the NiCoCr alloy actually improve at cryogenic temperatures to unprecedented levels of strengths above 1.3 GPa, failure strains up to 90% and K JIc values of 275 MPa.m 1/2 (with crackgrowth toughnesses above 400 MPa.m 1/2). These properties appear to result from continuous steady strain hardening, which acts to suppress plastic instability, resulting from pronounced dislocation activity and deformation-induced nano-twinning.« less

Exposure to volatile organic compounds for individuals with occupations associated with potential exposure to motor vehicle exhaust and/or gasoline vapor emissions.

PubMed

Jo, W K; Song, K B

2001-03-26

Workers who work near volatile organic compounds (VOCs) source(s), motor vehicle exhausts and/or gasoline vapor emissions, are suspected to be exposed to highly-elevated VOC levels during their work-time. This study confirmed this suspicion and evaluated the work-time exposure VOCs for traffic police officers, parking garage attendants, service station attendants, roadside storekeepers and underground storekeepers, by measuring the concentrations of six aromatic VOCs in workplace air, or personal air and breath samples. For nearly all target VOCs, the post-work breath concentrations of the workers were slightly or significantly higher than the pre-work breath concentrations, depending on the compound and occupation. Furthermore, both the pre- and post-work breath concentrations of the workers showed elevated levels compared with a control group of college students. The post-work breath concentrations were significantly correlated with the personal air concentrations, while the pre-work breath concentrations were not. Smoking workers were not always exposed to higher aromatic VOC levels than non-smoking workers. The breath and personal air concentrations for all the target compounds were both higher for underground parking garage attendants than for ground-level parking attendants. For all the target compounds except toluene, storekeepers exhibited similar levels of exposure for all store types. Print shopkeepers recorded the highest toluene exposure.

Genetic association with low concentrations of high density lipoprotein-cholesterol in a pediatric population of the Middle East and North Africa: the CASPIAN-III study.

PubMed

Kelishadi, Roya; Haghjooy Javanmard, Shaghayegh; Tajadini, Mohammad Hasan; Mansourian, Marjan; Motlagh, Mohammad Esmaeil; Ardalan, Gelayol; Ban, Matthew

2014-11-01

Depressed high-density lipoprotein cholesterol (HDL-C) is prevalent the Middle East and North Africa. Some studies have documented associations between HDL-C and several single nucleotide polymorphisms (SNPs) in candidate gene polymorphisms. We investigated the associations between SNP genotypes and HDL-C levels in Iranian students, aged 10-18 years. Genotyping was performed in 750 randomly selected participants among those with low HDL-C levels (below 5th percentile), intermediate HDL-C levels (5-95th) and high HDL-C levels (above the 95th percentile). Minor allele frequencies (MAFs) of the SNPs of interest were compared between the three HDL-C groups. The vast majority of pairwise comparisons of MAFs between HDL-C groups were significant. Pairwise comparisons between low and high HDL-C groups showed significant between-group differences in MAFs for all SNPs, except for APOC3 rs5128. Pairwise comparisons between low and intermediate HDL-C groups showed significant between-group differences in MAFs for all SNPs, except for APOC3 rs5128 and APOA1 rs2893157. Pairwise comparisons between intermediate and high HDL-C groups showed significant between-group differences in MAFs for all SNPs, except for ABCA1 APOC3 rs5128 and APOA1 rs2893157. After adjustment for confounding factors, including age, sex, body mass index, low physical activity, consumption of saturated fats, and socioeconomic status, ABCA1 r1587K and CETP A373P significantly increased the risk of depressed HDL-C, and CETP Taq1 had a protective role. This study replicated several associations between HDL-C levels and candidate gene SNPs from genome-wide associations with HDL-C in Iranians from the pediatric age group. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Interlaboratory variability in the quantification of new generation antiepileptic drugs based on external quality assessment data.

PubMed

Williams, John; Bialer, Meir; Johannessen, Svein I; Krämer, Günther; Levy, René; Mattson, Richard H; Perucca, Emilio; Patsalos, Philip N; Wilson, John F

2003-01-01

To assess interlaboratory variability in the determination of serum levels of new antiepileptic drugs (AEDs). Lyophilised serum samples containing clinically relevant concentrations of felbamate (FBM), gabapentin (GBP), lamotrigine (LTG), the monohydroxy derivative of oxcarbazepine (OCBZ; MHD), tiagabine (TGB), topiramate (TPM), and vigabatrin (VGB) were distributed monthly among 70 laboratories participating in the international Heathcontrol External Quality Assessment Scheme (EQAS). Assay results returned over a 15-month period were evaluated for precision and accuracy. The most frequently measured compound was LTG (65), followed by MHD (39), GBP (19), TPM (18), VGB (15), FBM (16), and TGB (8). High-performance liquid chromatography was the most commonly used assay technique for all drugs except for TPM, for which two thirds of laboratories used a commercial immunoassay. For all assay methods combined, precision was <11% for MHD, FBM, TPM, and LTG, close to 15% for GBP and VGB, and as high as 54% for TGB (p < 0.001). Mean accuracy values were <10% for all drugs other than TGB, for which measured values were on average 13.9% higher than spiked values, with a high variability around the mean (45%). No differences in precision and accuracy were found between methods, except for TPM, for which gas chromatography showed poorer accuracy compared with immunoassay and gas chromatography-mass spectrometry. With the notable exception of TGB, interlaboratory variability in the determination of new AEDs was comparable to that reported with older-generation agents. Poor assay performance is related more to individual operators than to the intrinsic characteristics of the method applied. Participation in an EQAS scheme is recommended to ensure adequate control of assay variability in therapeutic drug monitoring.

Modification of the health-promoting value of potato tubers field grown under drought stress: emphasis on dietary antioxidant and glycoalkaloid contents in five native andean cultivars (Solanum tuberosum L.).

PubMed

Andre, Christelle M; Schafleitner, Roland; Guignard, Cédric; Oufir, Mouhssin; Aliaga, Carlos Alberto Alvarado; Nomberto, Giannina; Hoffmann, Lucien; Hausman, Jean-François; Evers, Danièle; Larondelle, Yvan

2009-01-28

The effects of drought stress on dietary antioxidant and glycoalkaloid contents in potato tubers were investigated using a selection of five native Andean cultivars. Both freshly harvested and 4 month-stored tubers were analyzed. Responses to drought stress were highly cultivar-specific. The antioxidant contents of the yellow tuber-bearing cultivars (Sipancachi and SS-2613) were weakly affected by the drought treatment, whereas the pigmented cultivars demonstrated highly cultivar-dependent variations. A drastic reduction of anthocyanins and other polyphenols was revealed in the red- (Sullu) and purple-fleshed (Guincho Negra) cultivars, whereas an increase was shown in the purple-skinned and yellow-fleshed cultivar (Huata Colorada). The hydrophilic antioxidant capacity (evaluated by Folin-Ciocalteu and H-oxygen radical absorbance capacity assays) was highly correlated with the polyphenol content and followed, therefore, the same behavior upon drought. Carotenoid contents, including beta-carotene, as well as vitamin E, tended to increase or remain stable following drought exposure, except for the cultivar Sullu, in which the level of these lipophilic antioxidants was decreased. Vitamin C contents were not affected by drought with the exception of Guincho Negra, in which the level was increased. These variations of health-promoting compounds were associated with increased or stable levels of the toxic glycoalkaloids, alpha-solanine and alpha-chaconine. Storage at 10 degrees C for 4 months tended to decrease the concentrations of all dietary antioxidants, except those of vitamin E. This storage also reduced the drought-induced variations observed in freshly harvested tubers. These results were discussed in terms of their implications for human diet and health as well as in plant stress defense mechanisms.

Ferri-magnetic order in Mn induced spinel Co3-xMnxO4 (0.1≤x≤1.0) ceramic compositions

NASA Astrophysics Data System (ADS)

Meena, P. L.; Sreenivas, K.; Singh, M. R.; Kumar, Ashok; Singh, S. P.; Kumar, Ravi

2016-04-01

We report structural and magnetic properties of spinel Co3-xMnxO4 (x=0.1-1.0) synthesized by solid state reaction technique. Rietveld refinement analysis of X-ray diffraction (XRD) data, revealed the formation of polycrystalline single phase Co3-xMnxO4 without any significant structural change in cubic crystal symmetry with Mn substitution, except change in lattice parameter. Temperature dependent magnetization data show changes in magnetic ordering temperature, indicating formation of antiferromagnetic (AFM) and ferrimagnetic (FM) phase at low Mn concentration (x≤0.3) and well-defined FM phase at high Mn concentration (x≥0.5). The isothermal magnetization records established an AFM/FM mixed phase for composition ranging 0.10.5.

Global Diffusion Pattern and Hot SPOT Analysis of Vaccine-Preventable Diseases

NASA Astrophysics Data System (ADS)

Jiang, Y.; Fan, F.; Zanoni, I. Holly; Li, Y.

2017-10-01

Spatial characteristics reveal the concentration of vaccine-preventable disease in Africa and the Near East and that disease dispersion is variable depending on disease. The exception is whooping cough, which has a highly variable center of concentration from year to year. Measles exhibited the only statistically significant spatial autocorrelation among all the diseases under investigation. Hottest spots of measles are in Africa and coldest spots are in United States, warm spots are in Near East and cool spots are in Western Europe. Finally, cases of measles could not be explained by the independent variables, including Gini index, health expenditure, or rate of immunization. Since the literature confirms that each of the selected variables is considered determinants of disease dissemination, it is anticipated that the global dataset of disease cases was influenced by reporting bias.

Effect of surfactants on sorption of atrazine by soil

NASA Astrophysics Data System (ADS)

Abu-Zreig, Majed; Rudra, R. P.; Dickinson, W. T.; Evans, L. J.

1999-03-01

This study investigates the effect of synthetic wastewater containing surfactants on the sorption of atrazine using an equilibrium batch technique. Laboratory experiments were conducted on three soils with two non-ionic (Rexol and Rexonic) surfactants and one anionic (Sulphonic) surfactant, specifically manufactured for the detergent industry. Four sets of experiments were conducted to examine the influence of surfactants on the equilibrium time of atrazine sorption, to explore the effect of surfactant concentration, pH and type of surfactant on the amount of atrazine sorbed and to determine sorption isotherms of atrazine in the presence of surfactants. The results indicate that the application of Sulphonic results in dramatic increase in the adsorption of atrazine on to soils, the increase being directly proportional to the concentration of the surfactant. Application of the Sulphonic surfactants with a concentration of 3000 mg/l can result in a significant increase in Kd values of atrazine for loam and sandy loam soils. On the other hand, the effect of non-ionic surfactants depends on their concentration. Generally, non-ionic surfactants can result in a slight increase in atrazine sorption at high concentration, an exception being Rexol on sandy loam soil. At low concentrations, non-ionic surfactants have shown a tendency to decrease atrazine sorption.

Humidity-insensitive water evaporation from molecular complex fluids.

PubMed

Salmon, Jean-Baptiste; Doumenc, Frédéric; Guerrier, Béatrice

2017-09-01

We investigated theoretically water evaporation from concentrated supramolecular mixtures, such as solutions of polymers or amphiphilic molecules, using numerical resolutions of a one-dimensional model based on mass transport equations. Solvent evaporation leads to the formation of a concentrated solute layer at the drying interface, which slows down evaporation in a long-time-scale regime. In this regime, often referred to as the falling rate period, evaporation is dominated by diffusive mass transport within the solution, as already known. However, we demonstrate that, in this regime, the rate of evaporation does not also depend on the ambient humidity for many molecular complex fluids. Using analytical solutions in some limiting cases, we first demonstrate that a sharp decrease of the water chemical activity at high solute concentration leads to evaporation rates which depend weakly on the humidity, as the solute concentration at the drying interface slightly depends on the humidity. However, we also show that a strong decrease of the mutual diffusion coefficient of the solution enhances considerably this effect, leading to nearly independent evaporation rates over a wide range of humidity. The decrease of the mutual diffusion coefficient indeed induces strong concentration gradients at the drying interface, which shield the concentration profiles from humidity variations, except in a very thin region close to the drying interface.

Simulation of summertime ozone over North America

NASA Technical Reports Server (NTRS)

Jacob, Daniel J.; Logan, Jennifer A.; Yevich, Rose M.; Gardner, Geraldine M.; Spivakovsky, Clarisa M.; Wofsy, Steven C.; Munger, J. W.; Sillman, Sanford; Prather, Michael J.; Rogers, Michael O.

1993-01-01

The concentrations of O3 and its precursors over North America are simulated for three summer months with a 3D, continental-scale photochemical model using meteorological input from the Goddard Institute for Space Studies (GISS) GCM. The model has 4 x 5 deg grid resolution and represents nonlinear chemistry in urban and industrial plumes with a subgrid nested scheme. Simulated median afternoon O3 concentrations at rural U.S. sites are within 5 ppb of observations in most cases, except in the south central U.S., where concentrations are overpredicted by 15-20 ppb. The model captures successfully the development of regional high-O3 episodes over the northeastern United States on the back side of weak, warm, stagnant anticyclones. Simulated concentrations of CO and nonmethane hydrocarbons are generally in good agreement with observations, concentrations of NO(x) are underpredicted by 10-30 percent, and concentrations of PANs are overpredicted by a factor of 2 to 3. The overprediction of PANs is attributed to flaws in the photochemical mechanism, including excessive production from oxidation of isoprene, and may also reflect an underestimate of PANs deposition. Subgrid nonlinear chemistry as captured by the nested plumes scheme decreases the net O3 production computed in the U.S. boundary layer by 8 percent on average.

Socio-demographic, lifestyle, and dietary determinants of essential and possibly-essential trace element levels in adipose tissue from an adult cohort.

PubMed

Rodríguez-Pérez, Celia; Vrhovnik, Petra; González-Alzaga, Beatriz; Fernández, Mariana F; Martin-Olmedo, Piedad; Olea, Nicolás; Fiket, Željka; Kniewald, Goran; Arrebola, Juan P

2018-05-01

There is increasing evidence linking levels of trace elements (TEs) in adipose tissue with certain chronic conditions (e.g., diabetes or obesity). The objectives of this study were to assess concentrations of a selection of nine essential and possibly-essential TEs in adipose tissue samples from an adult cohort and to explore their socio-demographic, dietary, and lifestyle determinants. Adipose tissue samples were intraoperatively collected from 226 volunteers recruited in two public hospitals from Granada province. Trace elements (Co, Cr, Cu, Fe, Mn, Mo, Se, V, and Zn) were analyzed in adipose tissue by high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). Data were collected on socio-demographic characteristics, lifestyle, diet, and health status by face-to-face interview. Predictors of TE concentrations were assessed by using multivariable linear and logistic regression. All TEs were detected in all samples with the exception of Se (53.50%). Iron, zinc, and copper showed the highest concentrations (42.60 mg/kg, 9.80 mg/kg, and 0.68 mg/kg, respectively). Diet was the main predictor of Cr, Fe, Mo, and Se concentrations. Body mass index was negatively associated with all TEs (β coefficients = -0.018 to -0.593, p = 0.001-0.090) except for Mn and V. Age showed a borderline-significant positive correlation with Cu (β = 0.004, p = 0.089). Residence in a rural or semi-rural area was associated with increased Co, Cr, Fe, Mo, Mn, V and Zn concentrations and with β coefficients ranging from 0.196 to 0.544 (p < 0.05). Furthermore, individuals with higher educational level showed increased Cr, Co, Fe and V concentrations (β coefficients = 0.276-0.368, p = 0.022-0.071). This is the first report on the distribution of these TEs in adipose tissue and on their determinants in a human cohort and might serve as an initial step in the elucidation of their clinical relevance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Helium isotopes in ferromanganese crusts from the central Pacific Ocean

USGS Publications Warehouse

Basu, S.; Stuart, F.M.; Klemm, V.; Korschinek, G.; Knie, K.; Hein, J.R.

2006-01-01

Helium isotopes have been measured in samples of two ferromanganese crusts (VA13/2 and CD29-2) from the central Pacific Ocean. With the exception of the deepest part of crust CD29-2 the data can be explained by a mixture of implanted solar- and galactic cosmic ray-produced (GCR) He, in extraterrestrial grains, and radiogenic He in wind-borne continental dust grains. 4He concentrations are invariant and require retention of less than 12% of the in situ He produced since crust formation. Loss has occurred by recoil and diffusion. High 4He in CD29-2 samples older than 42 Ma are correlated with phosphatization and can be explained by retention of up to 12% of the in situ-produced 4He. 3He/4He of VA13/2 samples varies from 18.5 to 1852 Ra due almost entirely to variation in the extraterrestrial He contribution. The highest 3He/4He is comparable to the highest values measured in interplanetary dust particles (IDPs) and micrometeorites (MMs). Helium concentrations are orders of magnitude lower than in oceanic sediments reflecting the low trapping efficiency for in-falling terrestrial and extraterrestrial grains of Fe-Mn crusts. The extraterrestrial 3He concentration of the crusts rules out whole, undegassed 4–40 μm diameter IDPs as the host. Instead it requires that the extraterrestrial He inventory is carried by numerous particles with significantly lower He concentrations, and occasional high concentration GCR-He-bearing particles.

Spatial and temporal variability in nutrient concentrations in surface waters of the Chattahoochee River basin near Atlanta, Georgia, USA

USGS Publications Warehouse

Peters, N.E.; Buell, G.R.; Frick, E.A.

1997-01-01

Nutrient concentrations from the early 1970s through 1995 were evaluated at several sites along the Chattahoochee River and its tributaries near Atlanta, to determine general patterns and processes controlling nutrient concentrations in the river. A spatial analysis was conducted on data collected in 1994 and 1995 from an intensive nutrient study of the Chattahoochee River and its tributaries by the Georgia Department of Natural Resources, Environmental Protection Division. The 1994-1995 data show step increases in ammonium (NH4-N), nitrite plus nitrate (NO2 + NO3-N), and total-phosphorus (Tot-P) concentrations in the river. The step increases occur downstream of two wastewater treatment facilities (WWTFs) and Peachtree Creek, a small tributary inflow with degraded water quality draining a predominantly urban and industrial area. Median NO2 + NO3-N and Tot-P concentrations in the mainstem increase downstream of these inputs from 0.5 to 1 mg 1-1 and from 0.04 to 0.13 mg 1-1, respectively. NH4-N concentrations were typically low with 95% of the 2575 observations less than 0.2 mg 1-1 throughout the river system, except some high values (>1 mg 1-1) in some tributaries, particularly near the central part of Atlanta. High NH4-N concentrations are attributed to sewage discharge as they also are associated with high biological oxygen demand and faecal coliform bacteria concentrations. Nutrient concentrations vary temporally. An assessment of four sites, two mainstem and two tributaries, from 1970 to 1995 indicates a progressive increase and variability in NO2 + NO3-N concentrations during the period. The progressive increase in NO2 + NO3-N concentrations and their variability is similar to that reported for surface waters throughout the world and for which increased fertilizer usage has been attributed. Tot-P concentrations increase at mainstem sites through the middle to late 1980s and decrease markedly thereafter, due to improvements to WWTFs and a 1990 phosphate detergent ban. NH4-N concentrations, although less pronounced than Tot-P, display a similar decrease from the late 1980s to 1995 at the four sites. Tot-P concentration variability has increased at the tributary sites since 1993, although recent concentrations, on average, are the lowest since 1970 at each of the four sites.

Using groundwater age distributions to understand changes in methyl tert-butyl ether (MtBE) concentrations in ambient groundwater, northeastern United States

USGS Publications Warehouse

Lindsey, Bruce; Ayotte, Joseph; Jurgens, Bryant; DeSimone, Leslie A.

2017-01-01

Temporal changes in methyl tert-butyl ether (MtBE) concentrations in groundwater were evaluated in the northeastern United States, an area of the nation with widespread low-level detections of MtBE based on a national survey of wells selected to represent ambient conditions. MtBE use in the U.S. peaked in 1999 and was largely discontinued by 2007. Six well networks, each representing specific areas and well types (monitoring or supply wells), were each sampled at 10 year intervals between 1996 and 2012. Concentrations were decreasing or unchanged in most wells as of 2012, with the exception of a small number of wells where concentrations continue to increase. Statistically significant increasing concentrations were found in one network sampled for the second time shortly after the peak of MtBE use, and decreasing concentrations were found in two networks sampled for the second time about 10 years after the peak of MtBE use. Simulated concentrations from convolutions of estimates for concentrations of MtBE in recharge water with age distributions from environmental tracer data correctly predicted the direction of MtBE concentration changes in about 65 percent of individual wells. The best matches between simulated and observed concentrations were found when simulating recharge concentrations that followed the pattern of national MtBE use. Some observations were matched better when recharge was modeled as a plume moving past the well from a spill at one point in time. Modeling and sample results showed that wells with young median ages and narrow age distributions responded more quickly to changes in the contaminant source than wells with older median ages and broad age distributions. Well depth and aquifer type affect these responses. Regardless of the timing of decontamination, all of these aquifers show high susceptibility for contamination by a highly soluble, persistent constituent.

Methane fluxes from tropical coastal lagoons surrounded bymangroves, Yucatán, Mexico

USGS Publications Warehouse

Chuang, Pei-Chuan; Young, Megan B.; Dale, Andrew W.; Miller, Laurence G.; Herrera-Silveira, Jorge A; Paytan, Adina

2017-01-01

Methane concentrations in the water column and emissions to the atmosphere were determined for three tropical coastal lagoons surrounded by mangrove forests on the Yucatán Peninsula, Mexico. Surface water dissolved methane was sampled at different seasons over a period of 2 years in areas representing a wide range of salinities and anthropogenic impacts. The highest surface water methane concentrations (up to 8378 nM) were measured in a polluted canal associated with Terminos Lagoon. In Chelem Lagoon, methane concentrations were typically lower, except in the polluted harbor area (1796 nM). In the relatively pristine Celestún Lagoon, surface water methane concentrations ranged from 41 to 2551 nM. Methane concentrations were negatively correlated with salinity in Celestún, while in Chelem and Terminos high methane concentrations were associated with areas of known pollution inputs, irrespective of salinity. The diffusive methane flux from surface lagoon water to the atmosphere ranged from 0.0023 to 15 mmol CH4 m−2 d−1. Flux chamber measurements revealed that direct methane release as ebullition was up to 3 orders of magnitude greater than measured diffusive flux. Coastal mangrove lagoons may therefore be an important natural source of methane to the atmosphere despite their relatively high salinity. Pollution inputs are likely to substantially enhance this flux. Additional statistically rigorous data collected globally are needed to better consider methane fluxes from mangrove-surrounded coastal areas in response to sea level changes and anthropogenic pollution in order to refine projections of future atmospheric methane budgets.

Methane fluxes from tropical coastal lagoons surrounded by mangroves, Yucatán, Mexico

NASA Astrophysics Data System (ADS)

Chuang, P.-C.; Young, M. B.; Dale, A. W.; Miller, L. G.; Herrera-Silveira, J. A.; Paytan, A.

2017-05-01

Methane concentrations in the water column and emissions to the atmosphere were determined for three tropical coastal lagoons surrounded by mangrove forests on the Yucatán Peninsula, Mexico. Surface water dissolved methane was sampled at different seasons over a period of 2 years in areas representing a wide range of salinities and anthropogenic impacts. The highest surface water methane concentrations (up to 8378 nM) were measured in a polluted canal associated with Terminos Lagoon. In Chelem Lagoon, methane concentrations were typically lower, except in the polluted harbor area (1796 nM). In the relatively pristine Celestún Lagoon, surface water methane concentrations ranged from 41 to 2551 nM. Methane concentrations were negatively correlated with salinity in Celestún, while in Chelem and Terminos high methane concentrations were associated with areas of known pollution inputs, irrespective of salinity. The diffusive methane flux from surface lagoon water to the atmosphere ranged from 0.0023 to 15 mmol CH4 m-2 d-1. Flux chamber measurements revealed that direct methane release as ebullition was up to 3 orders of magnitude greater than measured diffusive flux. Coastal mangrove lagoons may therefore be an important natural source of methane to the atmosphere despite their relatively high salinity. Pollution inputs are likely to substantially enhance this flux. Additional statistically rigorous data collected globally are needed to better consider methane fluxes from mangrove-surrounded coastal areas in response to sea level changes and anthropogenic pollution in order to refine projections of future atmospheric methane budgets.

Atmospheric Impacts of Emissions from Oil and Gas Development in the Uintah Basin, Utah, USA

NASA Astrophysics Data System (ADS)

Helmig, D.; Boylan, P. J.; Hueber, J.; Van Dam, B. A.; Mauldin, L.; Parrish, D. D.

2012-12-01

In the Uintah Basin in northeast Utah, USA, surface ozone levels during winter months have approached and on occasion exceeded the US National Ambient Air Quality Standard (NAAQS). Emissions from the extensive oil and gas exploration in this region are suspected to be the cause of these ozone episodes; however emission rates and photochemical processes are uncertain. During February 2012 continuous surface measurements and vertical profiling from a tethered balloon platform at the Horsepool site yielded high resolution boundary layer profile data on ozone and ozone precursor compounds, i.e. nitrogen oxides and volatile organic compounds as well as methane. Findings from this study were: 1. Surface ozone during the study period, which had no snow cover, did not exceed the NAAQS. 2. Nitrogen oxides varied from 1-50 ppbv pointing towards significant emission sources, likely from oil and gas operations. 3. Methane concentrations were elevated, reaching up to ~10 times its Northern Hemisphere (NH) atmospheric background. 3. Light non-methane hydrocarbons (NMHC) constituted the main fraction of volatile organic compounds. NMHC concentrations were highly elevated, exceeding levels seen in urban areas. 4. Ozone, methane, NOx and VOC showed distinct diurnal cycles, with large concentration increases seen at night, except for ozone, which showed the opposite behavior. 5. During nighttime concentrations of NOx, NMHC, and methane built up near the surface to levels that were much higher than their daytime concentrations. 6. Comparing NMHC to methane concentrations indicates a mass flux ratio of ~30% for total VOC/methane emissions for the Uintah Basin.

Preliminary experimental results of gas recycling subsystems except carbon dioxide concentration

NASA Astrophysics Data System (ADS)

Otsuji, K.; Sawada, T.; Satoh, S.; Kanda, S.; Matsumura, H.; Kondo, S.; Otsubo, K.

Oxygen concentration and separation is an essential factor for air recycling in a CELSS. Furthermore, if the value of the plant assimilatory quotient is not coincident with that of the animal respiratory quotient, the recovery of O2 from the concentrated CO2 through chemical methods will become necessary to balance the gas contents in a CELSS. Therefore, oxygen concentration and separation equipment using Salcomine and O2 recovery equipment, such as Sabatier and Bosch reactors, were experimentally developed and tested.

Using Plant Source as a Buffering Agent to Manipulating Rumen Fermentation in an In vitro Gas Production System.

PubMed

Kang, S; Wanapat, M

2013-10-01

The objective of this study was to investigate the effect of banana flower powder (BAFLOP) supplementation on gas production kinetics and rumen fermentation efficiency in in vitro incubation with different ratios of roughage to concentrate in swamp buffalo and cattle rumen fluid. Two male, rumen fistulated dairy steers and swamp buffaloes were used as rumen fluid donors. The treatments were arranged according to a 2×2×3 factorial arrangement in a Completely randomized design by using two ratios of roughage to concentrate (R:C; 75:25 and 25:75) and 3 levels of BAFLOP supplementation (0, 2 and 4% of dietary substrate) into two different kinds of rumen fluid (beef cattle and swamp buffalo). Under this investigation, the results revealed that the rumen ecology was affected by R:C ratio. The pH declined as a result of using high concentrate ratio; however, supplementation of BAFLOP could buffer the pH which led to an improvement of ruminal efficiency. BAFLOP supplementation affected acetic acid (C2) when the proportion of concentrate was increased. However, there were no effect on total volatile fatty acid (TVFA) and butyric acid (C4) by BAFLOP supplementation. The microbial community was affected by BAFLOP supplementation, especially the bacterial population. As revealed by real-time PCR, the populations of F. succinogenes and R. albus were reduced by the high concentrate treatments while that of R. flavafaciens were increased. The populations of three dominant cellulolytic bacteria were enhanced by BAFLOP supplementation, especially on high concentrate diet. BAFLOP supplementation did not influence the ammonia nitrogen (NH3-N) concentration, while R:C did. In addition, the in vitro digestibility was improved by either R:C or BAFLOP supplementation. The BAFLOP supplementation showed an effect on gas production kinetics, except for the gas production rate constant for the insoluble fraction (c), while treatments with high concentrate ratio resulted in the highest values. In addition, BAFLOP tended to increase gas production. Based on this study, it could be concluded that R:C had an effect on rumen ecology both in buffalo and cattle rumen fluid and hence, BAFLOP could be used as a rumen buffering agent for enhancing rumen ecology fed on high concentrate diet. It is recommended that level of BAFLOP supplementation should be at 2 to 4% of total dry matter of substrate. However, in vivo trials should be subsequently conducted to investigate the effect of BAFLOP in high concentrate diets on rumen ecology as well as ruminant production.

An episode of extremely high PM concentrations over Central Europe caused by dust emitted over the southern Ukraine

NASA Astrophysics Data System (ADS)

Birmili, W.; Schepanski, K.; Ansmann, A.; Spindler, G.; Tegen, I.; Wehner, B.; Nowak, A.; Reimer, E.; Mattis, I.; Müller, K.; Brüggemann, E.; Gnauk, T.; Herrmann, H.; Wiedensohler, A.; Althausen, D.; Schladitz, A.; Tuch, T.; Löschau, G.

2007-08-01

On 24 March 2007, the atmosphere over Central Europe was affected by an episode of exceptionally high mass concentrations of aerosol particles, most likely caused by a dust storm in the Southern Ukraine on the preceding day. At ground-based measurement stations in Slovakia, the Czech Republic, Poland and Germany PM10 mass concentrations rose to values between 200 and 1400 μg m-3. An evaluation of PM10 measurements from 360 monitoring stations showed that the dust cloud advanced along a narrow corridor at speeds of up to 70 km h-1. According to lidar observations over Leipzig, Germany, the high aerosol concentrations were confined to a homogeneous boundary layer of 1800 m height. The wavelength dependence of light extinction using both lidar and sun photometer measurements suggested the dominance of coarse particles during the main event. At a wavelength of 532 nm, relatively high volume extinction coefficients (300-400 Mm-1) and a particle optical depth of 0.65 was observed. In-situ measurements with an aerodynamic particle sizer at Melpitz, Germany, confirmed the presence of a coarse particle mode with a mode diameter >2 μm, whose maximum concentration coincided with that of PM10. A chemical particle analysis confirmed the dominance of non-volatile and insoluble matter in the coarse mode as well as high enrichments of Ti and Fe, which are characteristic of soil dust. A combination of back trajectory calculations and satellite images allowed to identify the dust source with confidence: On 23 March 2007, large amounts of dust were emitted from dried-out farmlands in the southern Ukraine, facilitated by wind gusts up to 100 km h-1. The unusual vertical stability and confined height of this dust layer as well as the rapid transport under dry conditions led to the conservation of high aerosol mass concentrations along the transect and thus to the extraordinary high aerosol concentrations over Central Europe. Our observations demonstrate the capacity of a combined apparatus of in situ and remote sensing measurements to characterise such a dust with a variety of aerosol parameters. As a conclusion, the description of dust emission, transport and transformation processes needs to be improved, especially when facing the possible effects of further anthropogenic desertification and climate change.

Plant-beneficial elements status assessment in soil-plant system in the vicinity of a chemical industry complex: shedding light on forage grass safety issues.

PubMed

Anjum, Naser A; Duarte, Armando C; Pereira, Eduarda; Ahmad, Iqbal

2015-02-01

Human health is closely linked with soils via plants, grazers, or plant-based products. This study estimated plant-beneficial elements (macronutrients: K, P; secondary macronutrients: Ca, Mg; micronutrients: Mo, Mn, Na, Ni, Se) in both soils and shoots of two forage grass species (Eriophorum angustifolium and Lolium perenne) prevalent in the vicinity of a chemical industry complex (Estarreja, Portugal). Both soils and plants from the chemical industrial areas exhibited differential concentrations of the studied elements. In soils, the role of contamination was evidenced as insignificant in context of its impact on all the tested macro and secondary macronutrients except P, and micronutrients such as Mo and Ni. In forage grass plant shoots, the role of contamination was evidenced as insignificant in relation to its impact on all the tested macro and secondary macronutrients except K. Between the two forage grass plants, high Se-harboring L. perenne cannot be recommended for its use as animal feed.

Geologic, hydrologic, and geochemical identification of flow paths in the Edwards Aquifer, northeastern Bexar and southern Comal Counties, Texas

USGS Publications Warehouse

Otero, Cassi L.

2007-01-01

The U.S. Geological Survey, in cooperation with the San Antonio Water System, conducted a 4-year study during 2002?06 to identify major flow paths in the Edwards aquifer in northeastern Bexar and southern Comal Counties (study area). In the study area, faulting directs ground water into three hypothesized flow paths that move water, generally, from the southwest to the northeast. These flow paths are identified as the southern Comal flow path, the central Comal flow path, and the northern Comal flow path. Statistical correlations between water levels for six observation wells and between the water levels and discharges from Comal Springs and Hueco Springs yielded evidence for the hypothesized flow paths. Strong linear correlations were evident between the datasets from wells and springs within the same flow path and the datasets from wells in areas where flow between flow paths was suspected. Geochemical data (major ions, stable isotopes, sulfur hexafluoride, and tritium and helium) were used in graphical analyses to obtain evidence of the flow path from which wells or springs derive water. Major-ion geochemistry in samples from selected wells and springs showed relatively little variation. Samples from the southern Comal flow path were characterized by relatively high sulfate and chloride concentrations, possibly indicating that the water in the flow path was mixing with small amounts of saline water from the freshwater/saline-water transition zone. Samples from the central Comal flow path yielded the most varied major-ion geochemistry of the three hypothesized flow paths. Central Comal flow path samples were characterized, in general, by high calcium concentrations and low magnesium concentrations. Samples from the northern Comal flow path were characterized by relatively low sulfate and chloride concentrations and high magnesium concentrations. The high magnesium concentrations characteristic of northern Comal flow path samples from the recharge zone in Comal County might indicate that water from the Trinity aquifer is entering the Edwards aquifer in the subsurface. A graph of the relation between the stable isotopes deuterium and delta-18 oxygen showed that, except for samples collected following an unusually intense rain storm, there was not much variation in stable isotope values among the flow paths. In the study area deuterium ranged from -36.00 to -20.89 per mil and delta-18 oxygen ranged from -6.03 to -3.70 per mil. Excluding samples collected following the intense rain storm, the deuterium range in the study area was -33.00 to -20.89 per mil and the delta-18 oxygen range was -4.60 to -3.70 per mil. Two ground-water age-dating techniques, sulfur hexafluoride concentrations and tritium/helium-3 isotope ratios, were used to compute apparent ages (time since recharge occurred) of water samples collected in the study area. In general, the apparent ages computed by the two methods do not seem to indicate direction of flow. Apparent ages computed for water samples in northeastern Bexar and southern Comal Counties do not vary greatly except for some very young water in the recharge zone in central Comal County.

Solar-Light-Driven Renewable Butanol Separation by Core-Shell Ag@ZIF-8 Nanowires.

PubMed

Liu, Xu; He, Liangcan; Zheng, Jianzhong; Guo, Jun; Bi, Feng; Ma, Xiang; Zhao, Kun; Liu, Yaling; Song, Rui; Tang, Zhiyong

2015-06-03

Core-shell Ag@ZIF-8 nanowires, where single Ag nanowires are coated with uniform zeolitic-imidazolate-framework-8 (ZIF-8) shells, successfully realize renewable adsorptive separation of low concentrations of butanol from an aqueous medium under solar light irradiation by taking advantage of the exceptional adsorption capability of the ZIF-8 shells toward butanol and the unique plasmonic photothermal effect of the Ag nanowire cores. Impressively, the high separation efficiency is maintained as almost unchanged, even after 10 adsorption/desorption cycles. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

How do yeast cells become tolerant to high ethanol concentrations?

PubMed

Snoek, Tim; Verstrepen, Kevin J; Voordeckers, Karin

2016-08-01

The brewer's yeast Saccharomyces cerevisiae displays a much higher ethanol tolerance compared to most other organisms, and it is therefore commonly used for the industrial production of bioethanol and alcoholic beverages. However, the genetic determinants underlying this yeast's exceptional ethanol tolerance have proven difficult to elucidate. In this perspective, we discuss how different types of experiments have contributed to our understanding of the toxic effects of ethanol and the mechanisms and complex genetics underlying ethanol tolerance. In a second part, we summarize the different routes and challenges involved in obtaining superior industrial yeasts with improved ethanol tolerance.

Nanographene reinforced carbon/carbon composites

NASA Astrophysics Data System (ADS)

Bansal, Dhruv

Carbon/Carbon Composites (CCC) are made of carbon reinforcement in carbon matrix and have high thermal stability and fatigue resistance. CCC are used in nose cones, heat shields and disc brakes of aircrafts due to their exceptional mechanical properties at high temperature. The manufacturing process of CCC involves a carbonization stage in which unwanted elements, except carbon, are eliminated from the polymer precursor. Carbonization results in the formation of voids and cracks due to the thermal mismatch between the reinforcement and the matrix and expulsion of volatiles from the polymer matrix. Thermal cracks and voids decrease the density and mechanical properties of the manufactured CCC. In this work, Nanographene Platelets (NGP) were explored as nanofillers to fill the voids/cracks and reduce thermal shrinkage in CCC. They were first compared with Vapor Grown Carbon Nanofibers (VGCNF) by dispersion of different concentrations (0.5wt%, 1.5wt%, 3wt%) in resole-type phenolic resin and were characterized to explore their effect on rheology, heat of reaction and wetting behavior. The dispersions were then cured to form nanocomposites and were characterized for morphology, flexure and thermal properties. Finally, NGP were introduced into the carbon/carboncomposites in two stages, first by spraying in different concentrations (0.5wt%, 1.5wt%, 3wt%, 5wt %) during the prepreg formation and later during densification by directly mixing in the corresponding densification mix. The manufactured NGP reinforced CCC were characterized for microstructure, porosity, bulk density and mechanical properties (Flexure and ILSS) which were further cross-checked by non-destructive techniques (vibration and ultrasonic). In this study, it was further found that at low concentration (≤ 1.5 wt%) NGP were more effective in increasing the heat of reaction and in decreasing the viscosity of the phenolic resin. The decrease in viscosity led to better wetting properties of NGP / phenolic dispersions compared to VGCNF/phenolic dispersions. In nanocomposites, at low concentration (≤ 1.5 wt%), NGP were effective in increasing the flexure strength, char content and lowering the porosity and coefficient of thermal expansion of neat phenolic resin. At higher concentration (>1.5wt%), NGP had a tendency to agglomerate and lost their effectiveness. The behavior observed in nanocomposites continued in manufactured CCC. The highest Inter Laminar Shear Strength (ILSS), flexure strength/modulus, stiffness and density was observed at 1.5 wt% NGP. In CCC at concentrations > 1.5 wt%, the properties (ILSS, flexure, stiffness, density) decreased due to agglomeration but they were still higher compared to that of neat CCC (without NGP).

Major effect of inherited rheology weakening in the crust and mantle on continental intraplate strain and seismicity rates

NASA Astrophysics Data System (ADS)

Gueydan, Frédéric; Mazzotti, Stephane

2017-04-01

Stable Continental Regions (SCR, i.e., intraplate) are commonly viewed as non-deforming and very high resistance lithosphere domains, except in localized regions of higher strain and seismicity rates that often related to fossilized tectonic zones acting as weaker domains (e.g., Rhine Graben, New Madrid). Two main categories of models have been proposed to explain strain concentration in SCR: Local stress concentration (fault intersection, erosion pulse, …) and local lithosphere weakness (high geotherm, mantle anisotropy, …). In order to test the respective role of these various parameters of the stress - rheology - strain relationship, we propose a simple 1D model to quantify first-order continental strain rate variations using laboratory and field-based rheology laws for the crust and mantle. In particular, we include new strain-weakening rheologies in order to simulate tectonic heritage. Within the framework of near-failure equilibrium between tectonic forces and strain rates, we show that inherited rheology weakening plays a fundamental role in allowing for and explaining strain and seismicity concentration in intraplate weak zones. A comparison with empirical strain rate estimations in SCR and intraplate weak zones shows that inherited weakening rheologies can increase local strain rates by as much as three orders of magnitude, about one to two orders higher than that permitted by other processes such as stress concentration, thermal anomaly, etc.

Autotoxicity and allelopathy of 3,4-dihydroxyacetophenone isolated from Picea schrenkiana needles.

PubMed

Ruan, Xiao; Li, Zhao-Hui; Wang, Qiang; Pan, Cun-De; Jiang, De-An; Wang, G Geoff

2011-10-24

Bioassay-guided fractionation of the diethyl ether fraction of a water extract of Picea schrenkiana needles led to the isolation of the phenolic compound 3,4-dihydroxy- acetophenone (DHAP). The allelopathic effects of DHAP were evaluated under laboratory conditions on P. schrenkiana, rice (Oryza sativa L.), wheat (Triticum aestivum L.), radish (Raphanus sativus L.), lettuce (Latuca sativa L.), cucumber (Cucumis sativus L.) and mung bean (Phaseolus radiatus L.). DHAP significantly inhibited seed germination and seedling growth of P. schrenkiana at concentrations of 2.5 mM and 0.5 mM (p < 0.05). Soil analysis revealed that P. schrenkiana forest soils contained exceptionally high DHAP concentrations (mean = 0.51 ± 0.03 mg/g dry soil), sufficient to inhibit natural P. schrenkiana recruitment. DHAP also exhibited strong allelopathic potential. It significantly inhibited wheat and lettuce seed germination at concentrations of 1 mM and 0.5 mM (p < 0.05). The active compound also completely inhibited root growth of the six test species at high concentrations. Our results suggest a dual role of DHAP, both as an allelochemical and as an autotoxicant. The potential for a single plant needle-leached compound to influence both inter- and intra-specific interactions emphasized the complex effects that plant secondary metabolites might have on plant population and community structure.

49 CFR 384.203 - Driving while under the influence.

Code of Federal Regulations, 2013 CFR

2013-10-01

... licensing sanctions the disqualifications prescribed in § 383.51(b) of this subchapter for driving a CMV... a CMV with an alcohol concentration of 0.04, except licensing sanctions including suspension... disqualifications prescribed in § 383.51(b) of this subchapter for driving a CMV with a 0.04 alcohol concentration...

49 CFR 384.203 - Driving while under the influence.

Code of Federal Regulations, 2010 CFR

2010-10-01

... licensing sanctions the disqualifications prescribed in § 383.51(b) of this subchapter for driving a CMV... a CMV with an alcohol concentration of 0.04, except licensing sanctions including suspension... disqualifications prescribed in § 383.51(b) of this subchapter for driving a CMV with a 0.04 alcohol concentration...

49 CFR 384.203 - Driving while under the influence.

Code of Federal Regulations, 2011 CFR

2011-10-01

... licensing sanctions the disqualifications prescribed in § 383.51(b) of this subchapter for driving a CMV... a CMV with an alcohol concentration of 0.04, except licensing sanctions including suspension... disqualifications prescribed in § 383.51(b) of this subchapter for driving a CMV with a 0.04 alcohol concentration...

49 CFR 384.203 - Driving while under the influence.

Code of Federal Regulations, 2012 CFR

2012-10-01

... licensing sanctions the disqualifications prescribed in § 383.51(b) of this subchapter for driving a CMV... a CMV with an alcohol concentration of 0.04, except licensing sanctions including suspension... disqualifications prescribed in § 383.51(b) of this subchapter for driving a CMV with a 0.04 alcohol concentration...

49 CFR 384.203 - Driving while under the influence.

Code of Federal Regulations, 2014 CFR

2014-10-01

... licensing sanctions the disqualifications prescribed in § 383.51(b) of this subchapter for driving a CMV... a CMV with an alcohol concentration of 0.04, except licensing sanctions including suspension... disqualifications prescribed in § 383.51(b) of this subchapter for driving a CMV with a 0.04 alcohol concentration...

40 CFR 62.14650 - How do I conduct the initial and annual performance test?

Code of Federal Regulations, 2010 CFR

2010-07-01

... part 60, Appendix A must be used for gas composition analysis, including measurement of oxygen...) All pollutant concentrations, except for opacity, must be adjusted to 7 percent oxygen using Equation... adjusted to 7 percent oxygen; Cmeas = pollutant concentration measured on a dry basis; (20.9−7) = 20.9...

40 CFR 62.14650 - How do I conduct the initial and annual performance test?

Code of Federal Regulations, 2011 CFR

2011-07-01

... part 60, Appendix A must be used for gas composition analysis, including measurement of oxygen...) All pollutant concentrations, except for opacity, must be adjusted to 7 percent oxygen using Equation... adjusted to 7 percent oxygen; Cmeas = pollutant concentration measured on a dry basis; (20.9−7) = 20.9...

Interactions of tamoxifen with distearoyl phosphatidylcholine multilamellar vesicles: FTIR and DSC studies

NASA Astrophysics Data System (ADS)

Bilge, Duygu; Sahin, Ipek; Kazanci, Nadide; Severcan, Feride

2014-09-01

Interactions of a non-steroidal antiestrogen drug, tamoxifen (TAM), with distearoyl-sn-glycero-3-phosphatidylcholine (DSPC) multilamellar liposomes (MLVs) were investigated as a function of drug concentration (1-15 mol%) by using two noninvasive techniques, namely Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). FTIR spectroscopy results show that increasing TAM concentrations (except 1 mol%) increased the wavenumbers of the CH2 stretching modes, implying an disordering effect for DSPC MLVs both in the gel and liquid crystalline phases. The bandwidth values of the CH2 stretchings except for 1 mol% increased when TAM concentrations increased for DSPC liposomes, indicating an increase in the dynamics of liposomes. The Cdbnd O stretching and PO2- antisymmetric double bond stretching bands were analyzed to study interactions of TAM with head groups of lipids. As the concentrations of TAM increased, dehydration occurred around these functional groups in the polar part of the lipids. The DSC studies on thermal properties of DSPC lipids indicate that TAM eliminated the pre transition, shifted the main phase transition to lower temperatures and broadened the phase transition curve of the liposomes.

76 FR 19381 - Buy American Exceptions Under the American Recovery and Reinvestment Act of 2009

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-07

... Green High Rise Apartments. An exception was also granted to the Housing Authority of the City of Runge... work, using CFRFC grant funds, in connection with the Bowling Green High Rise Apartments. The exception...

Organohalogen concentrations and feeding status in Atlantic salmon (Salmo salar L.) of the Baltic Sea during the spawning run.

PubMed

Vuorinen, Pekka J; Kiviranta, Hannu; Koistinen, Jaana; Pöyhönen, Outi; Ikonen, Erkki; Keinänen, Marja

2014-01-15

Changes in the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in Baltic salmon muscle were studied during the spawning migration from the southern Baltic Sea to rivers flowing into the northern Gulf of Bothnia and during the spawning period. The aim was to obtain information to facilitate the arrangement of salmon fisheries such that the human dioxin intake is taken into account. The EC maximum allowable total toxic equivalent concentration (WHO-TEQPCDD/F+PCB) was exceeded in the muscle of the majority of the migrating salmon, except in the Baltic Proper. The fresh-weight-based concentrations of all toxicant groups in salmon tended to be the lowest in the Baltic Proper and the Northern Quark, and all toxicant concentrations, except PCDDs and PCDFs, were significantly higher in the spawning salmon than in the salmon caught during the spawning run. The fat content of the salmon muscle decreased by 60% during the spawning run, and the lipid-based total toxicant concentrations were consequently 4.2-6.2 times higher during the spawning period than during the spawning migration. However, the toxicants were concentrated just before spawning, and thus there is no essential difference related to whether the salmon are caught in the sea or the recreational river fishery. © 2013.

Heavy Metals in Surface Soils in the Upper Reaches of the Heihe River, Northeastern Tibetan Plateau, China

PubMed Central

Bu, Jianwei; Sun, Ziyong; Zhou, Aiguo; Xu, Youning; Ma, Rui; Wei, Wenhao; Liu, Meng

2016-01-01

The upper reaches of the Heihe River have been regarded as a hotspot for phytoecology, climate change, water resources and hydrology studies. Due to the cold-arid climate, high elevation, remote location and poor traffic conditions, few studies focused on heavy metal contamination of soils have been conducted or reported in this region. In the present study, an investigation was performed to provide information regarding the concentration levels, sources, spatial distributions, and environmental risks of heavy metals in this area for the first time. Fifty-six surface soil samples collected from the study area were analyzed for Cr, Mn, Ni, Cu, Zn, As, Cd and Pb concentrations, as well as TOC levels. Basic statistics, concentration comparisons, correlation coefficient analysis and multivariate analyses coupled with spatial distributions were utilized to delineate the features and the sources of different heavy metals. Risk assessments, including geoaccumulation index, enrichment factor and potential ecological risk index, were also performed. The results indicate that the concentrations of heavy metals have been increasing since the 1990s. The mean values of each metal are all above the average background values in the Qinghai Province, Tibet, China and the world, except for that of Cr. Of special note is the concentration of Cd, which is extremely elevated compared with all background values. The distinguished ore-forming conditions and well-preserved, widely distributed limestones likely contribute to the high Cd concentration. Heavy metals in surface soils in the study area are primarily inherited from parent materials. Nonetheless, anthropogenic activities may have accelerated the process of weathering. Cd presents a high background concentration level and poses a severe environmental risk throughout the whole region. Soils in Yinda, Reshui daban, Kekeli and Zamasheng in particular pose threats to the health of the local population, as well as that of livestock and wildlife. PMID:26907322

Responses of aquatic organisms to metal pollution in a lowland river in Flanders: a comparison of diatoms and macroinvertebrates.

PubMed

De Jonge, Maarten; Van de Vijver, Bart; Blust, Ronny; Bervoets, Lieven

2008-12-15

The role of macroinvertebrates and diatoms as indicator for metal pollution was investigated by assessing both biota along a metal gradient in the Belgian river the Dommel. Macroinvertebrates and diatoms were sampled in summer and winter and physical-chemical characteristics of the water were measured at four different sample periods and related to sediment characteristics. Although metal concentrations, except cadmium, in the water nowhere exceeded water quality standards, high metal concentrations were measured in the sediment, indicating historical contamination of the Dommel. At the sites that were situated downstream of the pollution source, high levels of conductivity and chloride were measured in the water. Redundancy Analysis (RDA) indicated pH, phosphate and zinc as the significant environmental variables explaining each respectively 7.7%, 11.6% and 22.6% of the macroinvertebrate community composition. Two clusters could be separated, with Gammarus pulex, Leptocerus interruptus, Baetis rhodani and Cloeon dipterum associated with low zinc concentrations and Tubificidae, Asellus aquaticus, Erpobdella sp. and Chironomus thummi-plumosus associated with higher zinc concentrations. Ammonium (10.6%), conductivity (16.5%), chloride (11.4%) and zinc (5.9%) turned out to be significant variables explaining the diatom community structure. Based on physical-chemical differences and species composition, three different groups could be separated. With this Tabellaria flocculosa and Fragilaria capucina var. rumpens were associated with low metal concentrations, Gomphonema parvulum and Nitzschia palea with elevated concentrations and Eolimna minima and Sellaphora seminulum with high zinc concentrations. In conclusion, the diatom community best reflected the metal gradient. With regard to water quality indices, those based on macroinvertebrates best followed the metal pollution gradient and were most strongly correlated with physical-chemical variables of water and sediment. This study indicated that to assess the effect of metal pollution in lowland rivers, the combined use of macroinvertebrates and diatoms is more appropriate than the use of both biota separately.

Water quality in the lower Puyallup River valley and adjacent uplands, Pierce County, Washington

USGS Publications Warehouse

Ebbert, J.C.; Bortleson, Gilbert C.; Fuste, L.A.; Prych, E.A.

1987-01-01

The quality of most ground and surface water within and adjacent to the lower Puyallup River valley is suitable for most typical uses; however, some degradation of shallow groundwater quality has occurred. High concentrations of iron and manganese were found in groundwater, sampled at depths of < 40 ft, from wells tapping alluvial aquifers and in a few wells tapping deeper aquifers. Volatile and acid- and base/neutral-extractable organic compounds were not detected in either shallow or deep groundwater samples. The quality of shallow groundwater was generally poorer than that of deep water. Deep ground water (wells set below 100 ft) appears suitable as a supplementary water supply for fish-hatchery needs. Some degradation of water quality, was observed downstream from river mile 1.7 where a municipal wastewater-treatment plant discharges into the river. In the Puyallup River, the highest concentrations of most trace elements were found in bed sediments collected downstream from river mile 1.7. Median concentrations of arsenic, lead, and zinc were higher in bed sediments from small streams compared with those from the Puyallup River, possibly because the small stream drainages, which are almost entirely within developed areas, receive more urban runoff as a percentage of total flow. Total-recoverable trace-element concentrations exceeded water-quality criteria for acute toxicity in the Puyallup River and in some of the small streams. In most cases, high concentrations of total-recoverable trace elements occurred when suspended-sediment concentrations were high. Temperatures in all streams except Wapato Creek and Fife Dutch were within limits (18 C) for Washington State class A water. Minimum dissolved oxygen concentrations were relatively low at 5.6 and 2.0 mg/L, respectively, for Wapato Creek and Fife Dutch. The poorest surface-water quality, which can be characterized as generally unsuitable for fish, was in Fife Dutch, a manmade channel and therefore uncharacteristic of other small streams. (Author 's abstract)

Patulin surveillance in apple cider and juice marketed in Michigan.

PubMed

Harris, Kerri L; Bobe, Gerd; Bourquin, Leslie D

2009-06-01

Patulin is the most common mycotoxin found in apples and apple juices. The objective of this study was to determine the concentrations of patulin in (i) apple cider produced and marketed by Michigan apple cider mills during the fall seasons of 2002 to 2003 and 2003 to 2004 and (ii) apple juice and cider, including shelf-stable products, marketed in retail grocery stores in Michigan throughout 2005 and 2006. End product samples (n=493) obtained from 104 Michigan apple cider mills were analyzed for patulin concentration by using solid-phase extraction followed by high-performance liquid chromatography. Patulin was detected (> or =4 microg/liter) in 18.7% of all cider mill samples, with 11 samples (2.2%) having patulin concentrations of > or =50 microg/liter. A greater percentage of cider samples obtained from mills using thermal pasteurization contained detectable patulin (28.4%) than did those from mills using UV light radiation (13.5%) or no pathogen reduction treatment (17.0%). Among retail grocery store samples (n=159), 23% of apple juice and cider samples contained detectable patulin, with 18 samples (11.3%) having patulin concentrations of > or =50 microg/liter. The U.S. Food and Drug Administration (FDA) action level for patulin is 50 microg/kg. Some apple juice samples obtained from retail grocery stores had exceptionally high patulin concentrations, ranging up to 2700 microg/liter. Collectively, these results indicate that most apple cider and juice test samples from Michigan were below the FDA action level for patulin but that certain apple cider and juice processors have inadequate controls over patulin concentrations in final products. The industry, overall, should focus on improved quality of fruit used in juice production and improve culling procedures to reduce patulin concentrations.

Measurement-model comparison of stabilized Criegee intermediate and highly oxygenated molecule production in the CLOUD chamber

NASA Astrophysics Data System (ADS)

Sarnela, Nina; Jokinen, Tuija; Duplissy, Jonathan; Yan, Chao; Nieminen, Tuomo; Ehn, Mikael; Schobesberger, Siegfried; Heinritzi, Martin; Ehrhart, Sebastian; Lehtipalo, Katrianne; Tröstl, Jasmin; Simon, Mario; Kürten, Andreas; Leiminger, Markus; Lawler, Michael J.; Rissanen, Matti P.; Bianchi, Federico; Praplan, Arnaud P.; Hakala, Jani; Amorim, Antonio; Gonin, Marc; Hansel, Armin; Kirkby, Jasper; Dommen, Josef; Curtius, Joachim; Smith, James N.; Petäjä, Tuukka; Worsnop, Douglas R.; Kulmala, Markku; Donahue, Neil M.; Sipilä, Mikko

2018-02-01

Atmospheric oxidation is an important phenomenon which produces large quantities of low-volatility compounds such as sulfuric acid and oxidized organic compounds. Such species may be involved in the nucleation of particles and enhance their subsequent growth to reach the size of cloud condensation nuclei (CCN). In this study, we investigate α-pinene, the most abundant monoterpene globally, and its oxidation products formed through ozonolysis in the Cosmic Leaving OUtdoor Droplets (CLOUD) chamber at CERN (the European Organization for Nuclear Research). By scavenging hydroxyl radicals (OH) with hydrogen (H2), we were able to investigate the formation of highly oxygenated molecules (HOMs) purely driven by ozonolysis and study the oxidation of sulfur dioxide (SO2) driven by stabilized Criegee intermediates (sCIs). We measured the concentrations of HOM and sulfuric acid with a chemical ionization atmospheric-pressure interface time-of-flight (CI-APi-TOF) mass spectrometer and compared the measured concentrations with simulated concentrations calculated with a kinetic model. We found molar yields in the range of 3.5-6.5 % for HOM formation and 22-32 % for the formation of stabilized Criegee intermediates by fitting our model to the measured sulfuric acid concentrations. The simulated time evolution of the ozonolysis products was in good agreement with measured concentrations except that in some of the experiments sulfuric acid formation was faster than simulated. In those experiments the simulated and measured concentrations met when the concentration reached a plateau but the plateau was reached 20-50 min later in the simulations. The results shown here are consistent with the recently published yields for HOM formation from different laboratory experiments. Together with the sCI yields, these results help us to understand atmospheric oxidation processes better and make the reaction parameters more comprehensive for broader use.

OSL and pollen concentrate 14C dating of dammed lake sediments at Maoxian, east Tibet, and implications for two historical earthquakes in AD 638 and 952

NASA Astrophysics Data System (ADS)

Xu, H.; Jiang, H.; Yu, S.; Yang, H.; Chen, J.

2016-12-01

Formation of dammed lakes provides exceptionally important information of continental geological processes, responding to tectonic and climatic influences. Establishing accurate geochronological frameworks within lake strata is challenging because the stratigraphy is often bereft of biostratigraphy and directly dateable material. Optically Stimulated Luminescence (OSL) and AMS 14C dating of pollen concentrates are well-established tools for dating lake sediments. Whether they are suitable for lake sediments in high-alpine settings remains uncertain. In this study, OSL and AMS 14C dating of pollen concentrate were conducted on the Diaolin section in a high-alpine setting in the eastern Tibetan Plateau. Good match of both dating results suggests that they are fit for dating lake sediments in high alpine settings. More than 300 g of sediment is required for preparation of pollen concentrates. During the pretreatment, 3% NaOH solution should be added to the sample, and then heated until just boiling ( 5 min) because NaOH treatment easily destroys pollen grains. Applying the heavy liquid flotation with specific gravity of 1.74-1.76 is useful to isolate relatively pure pollen grains. Sieving with a 20-μm and 63-μm mesh can concentrate pollen grains substantially. The OSL and AMS 14C dating yielded the basal age of the Diaolin section (650 AD). This indicates that the dammed-lake formed around 650 AD, probably caused by the earthquake occurring in the study area in 638 AD. The seismites characterized by soft-sediment deformation and phyllite layer happened at 780-980 AD, probably corresponding to the earthquake occurring on November 20, 952 AD in the study area.

Structure and mechanical properties of coatings fabricated by nonvacuum electron beam cladding of Ti-Ta-Zr powder mixtures

NASA Astrophysics Data System (ADS)

Samoylenko, Vitaliy V.; Lenivtseva, Olga G.; Polyakov, Igor A.; Laptev, Ilya S.

2015-10-01

In this paper structural investigations and mechanical tests of Ti-Ta-Zr coatings obtained on surfaces of cp-titanium workpieces were carried out. It was found that the coatings had a dendrite structure; investigations at high-power magnifications revealed a platelet structure. An increase of tantalum concentration led to refinement of structural components. The microhardness level of all coatings, excepting a specimen with the maximum tantalum content, was 370 HV. The microhardness of this coating reached 400 HV. The ultimate tensile strength of cladded layers varied from 697 to 947 MPa. Adhesion tests showed that bimetallic composites were characterized by high bond strength of cladded layers to the substrate, which exceeded cp-titanium strength characteristics.

Evaluation of synthetic/reconstituted high-density lipoproteins as delivery vehicles for paclitaxel.

PubMed

McConathy, Walter J; Nair, Maya P; Paranjape, Sulabha; Mooberry, Linda; Lacko, Andras G

2008-02-01

Reconstituted (synthetic) high-density lipoprotein particles carrying paclitaxel (rHDL/PTX) were prepared with substantially higher PTX content than reported earlier. The rHDL/PTX complexes seemed to be primarily spherical nanoparticles when examined via electron microscopy, with a constant composition, molecular weight and exceptional stability even after ultracentrifugation and storage for up to 6 months. The rHDL/PTX nanoparticles had superior cytotoxicity against several cancer cell lines (MCF7, DU145, OV1063 and OVCAR-3), the half maximal inhibitory concentration (IC50) having been found to be 5-20 times lower than that of the free drug. Studies with mice showed that the rHDL/PTX nanoparticles were substantially better tolerated than the corresponding dosages of either Taxol or Abraxane.

Comparison of five methods for extraction of Legionella pneumophila from respiratory specimens.

PubMed

Wilson, Deborah; Yen-Lieberman, Belinda; Reischl, Udo; Warshawsky, Ilka; Procop, Gary W

2004-12-01

The efficiencies of five commercially available nucleic acid extraction methods were evaluated for the recovery of a standardized inoculum of Legionella pneumophila in respiratory specimens (sputum and bronchoalveolar lavage [BAL] specimens). The concentrations of Legionella DNA recovered from sputa with the automated MagNA Pure (526,200 CFU/ml) and NucliSens (171,800 CFU/ml) extractors were greater than those recovered with the manual methods (i.e., Roche High Pure kit [133,900 CFU/ml], QIAamp DNA Mini kit [46,380 CFU/ml], and ViralXpress kit [13,635 CFU/ml]). The rank order was the same for extracts from BAL specimens, except that for this specimen type the QIAamp DNA Mini kit recovered more than the Roche High Pure kit.

Trace element accumulation in bivalve mussels Anodonta woodiana from Taihu Lake, China.

PubMed

Liu, Hongbo; Yang, Jian; Gan, Juli

2010-11-01

Data are presented for 13 trace metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, and Pb) in 38 bivalve mussels Anodonta woodiana from four separate sites (Huzhou, Dapu, Sansandao, and Manshan) around the Taihu Lake of China. All elemental concentrations generally ranked in decreasing order, Mn > Fe > Zn > As ≈ Cu ≈ Cd ≈ Se > Pb > Mo ≈ Ag, except that Cr, Co, and Ni were not detected. Anodonta woodiana was able to bioaccumulate essential Mn and toxic Cd to the extremely high level of 19,240 and 53 mg/kg dry weight, respectively. Geographical differences in the concentrations of trace elements were usually significant between sampling sites except for As and Pb, and the mussels from Sanshandao site had mostly accumulated or were contaminated with essential and toxic elements. The residue level of Cd in A. woodiana from the Sanshandao and Manshan sites appeared to be even higher than those of the essential elements Cu and Se, and exceeded the corresponding maximum residue limits of China. The present study provides the most recent information on trace element bioaccumulation or contamination in Taihu Lake and, further, suggests that A. woodiana can be used as a suitable bioindicator for inland water environmental monitoring.

Soil-plant-animal continuum in relation to macro and micro mineral status of dairy cattle in subtropical hill agro ecosystem.

PubMed

Kumaresan, A; Bujarbaruah, K M; Pathak, K A; Brajendra; Ramesh, T

2010-04-01

The purpose of the present study was to study the soil-plant-animal continuum in subtropical hilly areas. Soil (n = 96), fodder (n = 96), and blood serum samples from dairy cattle (n = 120) were collected from eight districts of Mizoram, a hilly state in India. The samples were digested using diacid mixture (HNO(3):HClO(4); 10:4) and analyzed for macro (Ca, P, Mg, Na, and K) and micro (Cu, Co, Mn, Fe, and Zn) mineral concentrations. The macro and micro mineral concentrations varied among the different districts. The correlation values between fodder and cattle were significant for all the minerals studied except for P and K. The correlation value between fodder and cattle was highly significant (P < 0.01) for Ca (0.878), Mg (0.88), Cu (0.885), and Zn (0.928). However, such correlations were not observed between the mineral levels in cattle and mineral levels in soil except for Ca (0.782). Equations developed in the present study for prediction of Ca (R(2) = 0.797), Mg (R(2) = 0.777), Zn (R(2) = 0.937), Fe (R(2) = 0.861), and Cu (R(2) = 0.794) had significant R(2) values. Further, it is inferred that dairy cattle reared under smallholder production system were deficient in most of the minerals and supplementation of required minerals is essential for optimum production.

On-site infiltration of road runoff using pervious pavements with subjacent infiltration trenches as source control strategy.

PubMed

Fach, S; Dierkes, C

2011-01-01

The focus in this work was on subsoil infiltration of stormwater from parking lots. With regard to operation, reduced infiltration performance due to clogging and pollutants in seepage, which may contribute to contaminate groundwater, are of interest. The experimental investigation covered a pervious pavement with a subjacent infiltration trench draining an impervious area of 2 ha. In order to consider seasonal effects on the infiltration performance, the hydraulic conductivity was measured tri-monthly during monitoring with a mobile sprinkling unit. To assess natural deposits jointing, road bed, gravel of infiltration trenches and subsoil were analysed prior to commencement of monitoring for heavy metals, polycyclic aromatic and mineral oil type hydrocarbons. Furthermore, from 22 storm events, water samples of rainfall, surface runoff, seepage and ground water were analysed with regard to the above mentioned pollutants. The study showed that the material used for the joints had a major impact on the initial as well as the final infiltration rates. Due to its poor hydraulic conductivity, limestone gravel should not be used as jointing. Furthermore, it is recommended that materials for the infiltration facilities are ensured free of any contaminants prior to construction. Polycyclic aromatic and mineral oil type hydrocarbons were, with the exception of surface runoff, below detection limits. Heavy metal concentrations of groundwater were with the exception of lead (because of high background concentrations), below the permissible limits.

Effect of lipophilicity on in vivo iontophoretic delivery. II. Beta-blockers.

PubMed

Tashiro, Y; Sami, M; Shichibe, S; Kato, Y; Hayakawa, E; Itoh, K

2001-06-01

The objective of this study was to investigate the relationship between drug lipophilicity and the transdermal absorption processes in the iontophoretic delivery in vivo. Anodal iontophoresis of beta-blockers as model drugs having different lipophilicity (atenolol, pindolol, metoprolol, acebutolol, oxprenolol and propranolol) was performed with rats (electrical current, 0.625 mA/cm2; application period, 90 min), and the drug concentrations in skin, cutaneous vein and systemic vein were determined. Increasing the lipophilicity of beta-blockers caused a greater absorption into the skin. Exceptionally, it was found that pindolol had high skin absorption, irrespective of its hydrophilic nature. Further, the drug transfer rate from skin to cutaneous vein (R(SC)) was evaluated from the arterio-venous plasma concentration difference of drug in the skin. Normalized R(SC) by skin concentration showed a negative correlation with the logarithm of n-octanol/buffer partition coefficient (Log P, pH 7.4), suggesting the partitioning between stratum corneum and viable epidermis was a primary process to determine the transfer properties of beta-blockers to local blood circulation. Pindolol exhibited both high skin absorption and high transfer from skin to cutaneous vein. These characteristics of pindolol could be explained by the chemical structure, molecular size and hydrophilicity. These findings for pindolol should be valuable for the optimal design of drug candidates for iontophoretic transdermal delivery.

Arsenic, Cadmium, Chromium, Lead, Mercury and Selenium Concentrations in Pine Snakes (Pituophis melanoleucus) from the New Jersey Pine Barrens.

PubMed

Burger, Joanna; Gochfeld, Michael; Jeitner, Christian; Zappalorti, Robert; Pittfield, Taryn; DeVito, Emile

2017-05-01

Top trophic level predators are at risk from bioaccumulation of heavy metals from their prey. Using nondestructively collected tissues as a method of assessing metal concentrations in snakes is useful for populations that are threatened or declining. This paper reports concentrations of arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg), and selenium (Se) in tissues of Northern pine snakes (Pituophis melanoleucus) from the New Jersey Pine Barrens, a relatively pristine, undisturbed habitat. We also determined if skin is an appropriate indicator of internal concentrations and identified the factors (tissue, year of collection, length, sex) that might explain variations in metal concentrations. Because they can grow to 2-m long and live for 25 years, we suggest that these snakes might accumulate heavy metals. Multiple regression models were significant, explaining 16% (lead) to 61% (mercury) of variation by tissue type. For mercury and chromium, size also was significant. The highest concentrations were in liver and kidney for all metals, except chromium and lead. Mercury concentrations in tissues were within the range reported for other snakes and were below effects concentrations in reptiles. The concentrations in skin were correlated with all internal tissues for mercury and for all internal tissues except heart for cadmium. These data show that shed skin can be used as an indicator of metals in pine snakes and that, at present, concentrations of heavy metals in this population are within the range of those found in other snake species from uncontaminated sites.

Effects of forage:concentrate ratio and forage type on apparent digestibility, ruminal fermentation, and microbial growth in goats.

PubMed

Cantalapiedra-Hijar, G; Yáñez-Ruiz, D R; Martín-García, A I; Molina-Alcaide, E

2009-02-01

The effects of forage type and forage:concentrate ratio (F:C) on apparent nutrient digestibility, ruminal fermentation, and microbial growth were investigated in goats. A comparison between liquid (LAB) and solid (SAB)-associated bacteria to estimate microbial N flow (MNF) from urinary purine derivative excretion was also examined. Treatments were a 2 x 2 factorial arrangement of forage type (grass hay vs. alfalfa hay) and high vs. low F:C (70:30 and 30:70, respectively). Four ruminally cannulated goats were fed, at maintenance intake, 4 experimental diets according to a 4 x 4 Latin square design. High-concentrate diets resulted in greater (P < 0.001) nutrient digestibility except for ADF. However, CP digestibility increased (P < 0.001) only for the high-concentrate diets including grass hay. Likewise, N retention, ruminal NH(3)-N concentration, and urinary excretion of purine derivatives increased (P < 0.05) with increasing concentrate in animals fed diets based on grass hay (0.23 vs. 0.13 g of retained N/g of digested N, 30.1 vs. 12.9 mg of NH(3)-N/100 mL, and 11.5 vs. 8.40 mmol/d, respectively), but not (P > 0.05) when diets included alfalfa hay. Total protozoa numbers and holotricha proportion were greater and less (P < 0.001), respectively, in high- than in low-concentrate diets. The F:C affected (P < 0.001) ruminal pH but not total VFA concentration (P = 0.12). Ammonia-N concentration was similar (P = 0.13) over time, whereas pH, VFA concentration, and protozoa numbers differed (P < 0.001) among diets. Estimated MNF was strongly influenced by using either the purine bases:N ratio obtained in our experimental conditions or values reported in the literature for small ruminants. There was a F:C effect (P = 0.006) on MNF estimated from LAB but not from SAB. The effect of F:C shifting from 70:30 to 30:70 in goat diets depends on the type of forage used. The MNF measured in goats fed different diets was influenced by the bacterial pellet (LAB or SAB). In addition, the purine bases:N ratio values found were different from those reported in the literature, which underlines the need for these variables to be analyzed directly in pellets isolated from specific animals and experimental conditions.

Assessment of the effluent quality from a gold mining industry in Ghana.

PubMed

Acheampong, Mike A; Paksirajan, Kannan; Lens, Piet N L

2013-06-01

The physical and chemical qualities of the process effluent and the tailings dam wastewater of AngloGold-Ashanti Limited, a gold mining company in Ghana, were studied from June to September, 2010. The process effluent from the gold extraction plant contains high amounts of suspended solids and is therefore highly turbid. Arsenic, copper and cyanide were identified as the major pollutants in the process effluent with average concentrations of 10.0, 3.1 and 21.6 mg L(-1), respectively. Arsenic, copper, iron and free cyanide (CN(-)) concentrations in the process effluent exceeded the Ghana EPA discharge limits; therefore, it is necessary to treat the process effluent before it can be discharged into the environment. Principal component analysis of the data indicated that the process effluent characteristics were influenced by the gold extraction process as well as the nature of the gold-bearing ore processed. No significant correlation was observed between the wastewater characteristics themselves, except for the dissolved oxygen and the biochemical oxygen demand. The process effluent is fed to the Sansu tailings dam, which removes 99.9 % of the total suspended solids and 99.7 % of the turbidity; but copper, arsenic and cyanide concentrations were still high. The effluent produced can be classified as inorganic with a high load of non-biodegradable compounds. It was noted that, though the Sansu tailings dam stores the polluted effluent from the gold extraction plant, there will still be serious environmental problems in the event of failure of the dam.

Novel one-pot and facile room temperature synthesis of gold nanodots and application as highly sensitive and selective probes for cyanide detection

NASA Astrophysics Data System (ADS)

Vasimalai, Nagamalai; Fernandez-Arguelles, Maria T.

2016-11-01

Highly fluorescent gold nanodots have been synthesized through a novel rapid, facile and one-pot room temperature route using trithiocyanuric acid as mild reducing agent and surface ligand. The proposed synthesis overcomes limitations of other synthetic routes in terms of cost, time, complexity and environmental risks, and gives rise to highly fluorescent gold nanodots within 10 min at room temperature, with a maximum emission wavelength at 623 nm and a large Stokes shift (213 nm). Moreover, the synthesized gold nanodots showed a large emission QY (9.62 × 10-2) and excellent photostability and colloidal properties during long periods. Increasing concentrations of CN- in aqueous solution progressively quenched the fluorescence emission and produced a slight blue shift of the synthesized gold nanodots. A good linear relationship was observed for CN- concentrations between 0.29 and 8.87 μM, obtaining a detection limit estimated according to the 3s IUPAC criteria of 150 nM. Besides, the influence on the fluorescence signal of potential interferents at high concentrations (1000 μM) was studied, including I-, F-, citrate, {{{{PO}}}4}3-, {{{{NO}}}3}-, {{{{SO}}}4}2-, CH3COO-, EDTA, Br-, {{{{CO}}}3}2-, Cl- and S2- K+, Na+, Li+, Mg2+, Ca2+, Ba2+, Cu2+, Zn2+, Ni2+, Al3+, Fe2+, Fe3+, Pb2+, Cd2+, Hg2+ and Co2+. Results showed a high selectivity towards all the investigated ions, except for Pb2+, Cd2+ and Hg2+, although the use of glutathione and BSA as masking agents drastically minimized the effect of such cations at high concentrations. The synthesized gold nanodots were successfully evaluated as highly sensitive and selective probes for cyanide determination in environmental water samples, including tap, river, lake and sea water, indicating the validity of TCA-AuNDs for analytical CN- contamination control.

Seasonal variation of endocrine disrupting compounds, pharmaceuticals and personal care products in wastewater treatment plants.

PubMed

Yu, Yong; Wu, Laosheng; Chang, Andrew C

2013-01-01

The occurrence of 14 endocrine disrupting compounds (EDCs), pharmaceuticals and personal care products (PPCPs) in influents, effluents and sludge from five wastewater treatment plants (WWTPs) in southern California was studied in winter and summer. All 14 compounds were detected in influent samples from the five WWTPs except for estrone. Paracetamol, naproxen and ibuprofen were the dominant compounds, with mean concentrations of 41.7, 35.7 and 22.3 μg/L, respectively. The treatment removal efficiency for most compounds was more than 90% and concentrations in the effluents were relatively low. Seasonal variation of the compounds' concentration in the wastewater was significant: the total concentration of each compound in the wastewater was higher in winter than in summer, which is attributed to more human consumption of pharmaceuticals during winter and faster degradation of the compounds in summer. The highest concentrations of triclosan and octylphenol were detected in sewage sludge, with mean concentrations of 1505 and 1179 ng/g, respectively. Risk quotients (RQs), expressed as the ratios of environmental concentrations and the predicted no-effect concentrations (PNEC), were less than unity for all the compounds except for estrone in the effluents, indicating no immediate ecological risk is expected. However, RQs were higher than unity for 2 EDCs (estrone and octylphenol) and carbamazepine in sludge samples, indicating a significant ecotoxicological risk to human health. Therefore, appropriate treatment of sewage sludge is required before its application. Copyright © 2012 Elsevier B.V. All rights reserved.

Physiological Adaptations of Arctic Mammals.

DTIC Science & Technology

1975-01-01

photometry for sodium and potassium concentration. Data for the first 30 minute period of severe cold exposure is summarized in Table 1. All the urine...exception of the slope of potassium concentration of unacclimated brown lemmings (which increased), slopes of ion concentrations were not different from...between 5:00 AN and 9:00 AM. Interpretation of the sodium and potassium excretion ..n the urine is difficult as long as there are no specific data on

Lactobacillus rhamnosus GG Protects against Non-Alcoholic Fatty Liver Disease in Mice

PubMed Central

Ritze, Yvonne; Bárdos, Gyöngyi; Claus, Anke; Ehrmann, Veronika; Bergheim, Ina; Schwiertz, Andreas; Bischoff, Stephan C.

2014-01-01

Objective Experimental evidence revealed that obesity-associated non-alcoholic fatty liver disease (NAFLD) is linked to changes in intestinal permeability and translocation of bacterial products to the liver. Hitherto, no reliable therapy is available except for weight reduction. Within this study, we examined the possible effect of the probiotic bacterial strain Lactobacillus rhamnosus GG (LGG) as protective agent against experimental NAFLD in a mouse model. Methods Experimental NAFLD was induced by a high-fructose diet over eight weeks in C57BL/J6 mice. Fructose was administered via the drinking water containing 30% fructose with or without LGG at a concentration resulting in approximately 5×107 colony forming units/g body weight. Mice were examined for changes in small intestinal microbiota, gut barrier function, lipopolysaccharide (LPS) concentrations in the portal vein, liver inflammation and fat accumulation in the liver. Results LGG increased beneficial bacteria in the distal small intestine. Moreover, LGG reduced duodenal IκB protein levels and restored the duodenal tight junction protein concentration. Portal LPS (P≤0.05) was reduced and tended to attenuate TNF-α, IL-8R and IL-1β mRNA expression in the liver feeding a high-fructose diet supplemented with LGG. Furthermore liver fat accumulation and portal alanine-aminotransferase concentrations (P≤0.05) were attenuated in mice fed the high-fructose diet and LGG. Conclusions We show for the first time that LGG protects mice from NAFLD induced by a high-fructose diet. The underlying mechanisms of protection likely involve an increase of beneficial bacteria, restoration of gut barrier function and subsequent attenuation of liver inflammation and steatosis. PMID:24475018

Detrital and oceanic dysoxia influence on OAE2 sediment geochemistry from Tarfaya, SW Morocco

NASA Astrophysics Data System (ADS)

Turgeon, S. C.; Kolonic, S.; Brumsack, H.-J.; Wagner, T.

2003-04-01

The Cretaceous "greenhouse" world's stratigraphic record is punctuated by several important organic-rich intervals representing quasi-global "Oceanic Anoxic Events" (OAEs). This study focuses on sediments from Tarfaya in SW Morocco deposited during the Cenomanian-Turonian Boundary Event (CTBE or OAE2 at 93.5 Ma). These sediments consist of distinctly laminated, carbonate-rich black shales alternating with lighter coloured structureless intervals and sporadic chert lenses. Sediments from three sites representing proximal to distal settings were studied. Samples were analysed for Ctot, Corg, Stot, as well as several major-, minor- and trace elements using XRF and ICP-MS. These sediments are characterised by high Corg, Stot, and CaCO3 contents and consist of a simple two component mixing system ("average shale"-CaCO3). Major element concentrations are low, except for Ca and P, owing in part to the carbonate dilution effect. Most elements plot along "average shale" lines. Elements such as Si, Ti, Fe, K, Rb, and Zr show positive relationships with Al2O3, pointing to homogeneous source area material. Several Al-normalised elements (As, Ba, Cr, Cu, Ni, Sr, U, V, Y, Zn), many of them redox-sensitive or sulphide-residing, are enriched in the sediments indicating an oxygen-depleted environment and potential availability of hydrogen sulfide in the water column at the time of deposition. High Zn concentrations suggest increased submarine volcanism and/or hydrothermal activity during this time interval. High Ba concentrations are possibly indicative of high regional paleoproductivity, which is further supported by the elevated P concentrations hinting at nutrient availability. Basinward trends in the geochemical distribution of some elements are apparent and probably reflect the decreasing influence of terrestrial sediments away from the shoreline.

High residue levels and the chemical form of mercury in tissues and organs of seabirds

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

Kim, E.Y.; Murakami, Toru; Saeki, Kazutoshi

1995-12-31

Total and organic (methyl) mercury in liver, muscle, kidney and feather of 9 species of seabirds were analyzed to determine the levels and their distribution and to clarify the occurrences of high mercury levels and their detoxification process in seabirds. Total mercury levels in liver showed great variations in intra and interspecies, while organic mercury levels were less variable. As compared with species in relatively low mercury levels, the species which accumulated the high concentration of mercury like black-footed albatross exhibited the different distribution of mercury in the body: in total mercury burden, albatross species contained less than 10% inmore » feather and over 50% in liver, while other species contained over 40% in feather and less than 20% in liver. The order of organic mercury concentrations in tissues were as follows: liver > kidney > muscle in seabirds examined, except oldsquaw. The mean percentage of organic mercury in total was 35%, 66%, and 36% in liver, muscle and kidney, respectively, for all the species. The significant negative correlations were found between organic mercury percentage to total mercury and total mercury concentrations in the liver and muscle of black-footed albatross and in the liver of laysan albatross. Furthermore, in liver, muscle, and kidney of all the species, the percentages of organic mercury had a negative trend with an increase of total mercury concentrations. The results suggest that albatross species may be capable for demethylating organic mercury in the tissues (mainly in liver), and for storing the mercury as immobilizable inorganic form in the liver as substitution for delivering organic mercury to other organs. It is noteworthy that the species with high degree of demethylation showed the lower mercury burdens in feather and slow moulting pattern.« less

Effects of Insecticides and Fungicides Commonly Used in Tomato Production on Phytoseiulus persimilis (Acari: Phtyoseiidae).

PubMed

Ditillo, J L; Kennedy, G G; Walgenbach, J F

2016-12-01

The twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is an important pest of tomatoes in North Carolina. Resident populations of the predatory mite Phytoseiulus persimilis have recently been detected on field-grown tomatoes in central North Carolina, and potentially can be a useful biological control agent against T. urticae Laboratory bioassays were used to assess lethal and reproductive effects of 10 insecticides and five fungicides commonly used in commercial tomato production (chlorantraniliprole, spinetoram, permethrin, imidacloprid, dimethoate, dinotefuran, thiamethoxam, bifenthrin, fenpropathrin, lambda-cyhalothrin, azoxystrobin, chlorothalonil, boscalid, cyazofamid, and mancozeb) on P. persimilis adult females and eggs. Insecticides were tested using concentrations equivalent to 1×, 0.5×, and 0.1× of the recommended field rates. Fungicides were tested at the 1× rate only. Dimethoate strongly impacted P. persimilis with high adult mortality, reduced fecundity, and reduced hatch of eggs laid by treated adults, particularly at high concentrations. The pyrethroids lambda-cyhalothrin, bifenthrin, and fenpropathrin were associated with repellency and reproductive effects at high concentrations. Bifenthrin additionally caused increased mortality at high concentrations. Chlorantraniliprole, dinotefuran, and permethrin did not significantly affect mortality or reproduction. Imidacloprid significantly reduced fecundity and egg viability, but was not lethal to adult P. persimilis Thiamethoxam negatively impacted fecundity at the 1× rate. There were no negative effects associated with fungicide exposure with the exception of mancozeb, which impacted fecundity. Field trials were conducted to explore the in vivo impacts of screened insecticides on P. persimilis populations in the field. Field trials supported the incompatibility of dimethoate with P. persimilis populations. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Range of therapeutic metformin concentrations in clinical blood samples and comparison to a forensic case with death due to lactic acidosis.

PubMed

Hess, C; Unger, M; Madea, B; Stratmann, B; Tschoepe, D

2018-05-01

Due to a lack of reference values for blood concentration of metformin in the literature, the forensic evaluation of metformin findings in blood samples is difficult. Interpretations with regard to the assessment of blood concentrations as well as an estimation of the ingested metformin amounts are often vague. Furthermore, post mortem evaluation of death due to lactic acidosis because of metformin is difficult since renal performance or lactate concentrations can not always reliably be determined after death. To describe a concentration range in clinical samples after chronic use of metformin, metformin serum concentrations were determined in serum samples of 95 diabetic patients receiving daily doses of 500mg-3000mg of metformin. The analyses of metformin was carried out using a validated high performance liquid chromatograph coupled to triple quadrupole mass spectrometry (LC-QQQ-MS). On average, metformin concentrations were 1846ng/mL (

9 CFR 85.1 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Immunosorbent Assay (ELISA) Test, except for approved differential pseudorabies tests other than the glycoprotein I (gpI) ELISA test; 5. Latex Agglutination Test (LAT); and 6. Particle Concentration Fluorescence...

9 CFR 85.1 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Immunosorbent Assay (ELISA) Test, except for approved differential pseudorabies tests other than the glycoprotein I (gpI) ELISA test; 5. Latex Agglutination Test (LAT); and 6. Particle Concentration Fluorescence...

9 CFR 85.1 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Immunosorbent Assay (ELISA) Test, except for approved differential pseudorabies tests other than the glycoprotein I (gpI) ELISA test; 5. Latex Agglutination Test (LAT); and 6. Particle Concentration Fluorescence...

9 CFR 85.1 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Immunosorbent Assay (ELISA) Test, except for approved differential pseudorabies tests other than the glycoprotein I (gpI) ELISA test; 5. Latex Agglutination Test (LAT); and 6. Particle Concentration Fluorescence...

9 CFR 85.1 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Immunosorbent Assay (ELISA) Test, except for approved differential pseudorabies tests other than the glycoprotein I (gpI) ELISA test; 5. Latex Agglutination Test (LAT); and 6. Particle Concentration Fluorescence...

Modeling the Distribution of Migratory Bird Stopovers to Inform Landscape-Scale Siting of Wind Development

PubMed Central

Pocewicz, Amy; Estes-Zumpf, Wendy A.; Andersen, Mark D.; Copeland, Holly E.; Keinath, Douglas A.; Griscom, Hannah R.

2013-01-01

Conservation of migratory birds requires understanding the distribution of and potential threats to their migratory habitats. However, although migratory birds are protected under international treaties, few maps have been available to represent migration at a landscape scale useful to target conservation efforts or inform the siting of wind energy developments that may affect migratory birds. To fill this gap, we developed models that predict where four groups of birds concentrate or stopover during their migration through the state of Wyoming, USA: raptors, wetland, riparian and sparse grassland birds. The models were based on existing literature and expert knowledge concerning bird migration behavior and ecology and validated using expert ratings and known occurrences. There was significant agreement between migratory occurrence data and migration models for all groups except raptors, and all models ranked well with experts. We measured the overlap between the migration concentration models and a predictive model of wind energy development to assess the potential exposure of migratory birds to wind development and illustrate the utility of migratory concentration models for landscape-scale planning. Wind development potential is high across 15% of Wyoming, and 73% of this high potential area intersects important migration concentration areas. From 5.2% to 18.8% of each group’s important migration areas was represented within this high wind potential area, with the highest exposures for sparse grassland birds and the lowest for riparian birds. Our approach could be replicated elsewhere to fill critical data gaps and better inform conservation priorities and landscape-scale planning for migratory birds. PMID:24098379

Ammonia toxicity induces glutamine accumulation, oxidative stress and immunosuppression in juvenile yellow catfish Pelteobagrus fulvidraco.

PubMed

Li, Ming; Gong, Shiyan; Li, Qing; Yuan, Lixia; Meng, Fanxing; Wang, Rixin

2016-01-01

A study was carried to test the response of yellow catfish for 28 days under two ammonia concentrations. Weight gain of fish exposure to high and low ammonia abruptly increased at day 3. There were no significant changes in fish physiological indexes and immune responses at different times during 28-day exposure to low ammonia. Fish physiological indexes and immune responses in the treatment of high ammonia were lower than those of fish in the treatment of low ammonia. When fish were exposed to high ammonia, the ammonia concentration in the brain increased by 19-fold on day 1. By comparison, liver ammonia concentration reached its highest level much earlier at hour 12. In spite of a significant increase in brain and liver glutamine concentration, there was no significant change in glutamate level throughout the 28-day period. The total superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione reductase (GR) activities in the brain gradually decreased from hour 0 to day 28. Liver SOD, GPX and GR activities reached the highest levels at hour 12, and then gradually decreased. Thiobarbituric acid reactive substance brain and liver content gradually increased throughout the 28-day period. Lysozyme, acid phosphatase and alkaline phosphatase activities in the liver reached exceptionally low levels after day 14. This study indicated that glutamine accumulation in the brain was not the major cause of ammonia poisoning, the toxic reactive oxygen species is not fully counter acted by the antioxidant enzymes and immunosuppression is a process of gradual accumulation of immunosuppressive factors. Copyright © 2016 Elsevier Inc. All rights reserved.

Highly hydrogen-sensitive thermal desorption spectroscopy system for quantitative analysis of low hydrogen concentration (˜1 × 1016 atoms/cm3) in thin-film samples

NASA Astrophysics Data System (ADS)

Hanna, Taku; Hiramatsu, Hidenori; Sakaguchi, Isao; Hosono, Hideo

2017-05-01

We developed a highly hydrogen-sensitive thermal desorption spectroscopy (HHS-TDS) system to detect and quantitatively analyze low hydrogen concentrations in thin films. The system was connected to an in situ sample-transfer chamber system, manipulators, and an rf magnetron sputtering thin-film deposition chamber under an ultra-high-vacuum (UHV) atmosphere of ˜10-8 Pa. The following key requirements were proposed in developing the HHS-TDS: (i) a low hydrogen residual partial pressure, (ii) a low hydrogen exhaust velocity, and (iii) minimization of hydrogen thermal desorption except from the bulk region of the thin films. To satisfy these requirements, appropriate materials and components were selected, and the system was constructed to extract the maximum performance from each component. Consequently, ˜2000 times higher sensitivity to hydrogen than that of a commercially available UHV-TDS system was achieved using H+-implanted Si samples. Quantitative analysis of an amorphous oxide semiconductor InGaZnO4 thin film (1 cm × 1 cm × 1 μm thickness, hydrogen concentration of 4.5 × 1017 atoms/cm3) was demonstrated using the HHS-TDS system. This concentration level cannot be detected using UHV-TDS or secondary ion mass spectroscopy (SIMS) systems. The hydrogen detection limit of the HHS-TDS system was estimated to be ˜1 × 1016 atoms/cm3, which implies ˜2 orders of magnitude higher sensitivity than that of SIMS and resonance nuclear reaction systems (˜1018 atoms/cm3).

Technological properties of indigenous wine yeast strains isolated from wine production regions of Turkey.

PubMed

Bağder Elmacı, Simel; Özçelik, Filiz; Tokatlı, Mehmet; Çakır, İbrahim

2014-05-01

The purpose of this study was to evaluate the important technological and fermentative properties of wine yeast strains previously isolated from different wine producing regions of Turkey. The determination of the following important properties was made: growth at high temperatures; fermentative capability in the presence of high sugar concentration; fermentation rate; hydrogen sulfide production; killer activity; resistance to high ethanol and sulfur dioxide; foam production; and enzymatic profiles. Ten local wine yeast strains belonging to Saccharomyces, and one commercial active dry yeast as a reference strain were evaluated. Fermentation characteristics were evaluated in terms of kinetic parameters, including ethanol yield (YP/S), biomass yield (YX/S), theoretical ethanol yield (%), specific ethanol production rate (qp; g/gh), specific glucose uptake rate (qs; g/gh), and the substrate conversion (%). All tested strains were able to grow at 37 °C and to start fermentation at 30° Brix, and were resistant to high concentrations of sulfur dioxide. 60 % of the strains were weak H2S producers, while the others produced high levels. Foam production was high, and no strains had killer activity. Six of the tested strains had the ability to grow and ferment at concentrations of 14 % ethanol. Except for one strain, all fermented most of the media sugars at a high rate, producing 11.0-12.4 % (v/v) ethanol. Although all but one strain had suitable characteristics for wine production, they possessed poor activities of glycosidase, esterase and proteinase enzymes of oenological interest. Nine of the ten local yeast strains were selected for their good oenological properties and their suitability as a wine starter culture.

Tissue partition and risk assessments of trace elements in Indo-Pacific Finless Porpoises (Neophocaena phocaenoides) from the Pearl River Estuary coast, China.

PubMed

Zhang, Xiyang; Lin, Wenzhi; Yu, Ri-Qing; Sun, Xian; Ding, Yulong; Chen, Hailiang; Chen, Xi; Wu, Yuping

2017-10-01

Throughout the last few decades, an increased number of stranded marine mammals, particularly the Indo-Pacific Finless Porpoises (Neophocaena phocaenoides), were observed in the Pearl River Estuary (PRE). As long-lived, apex predators vulnerable to bioaccumulation of contaminants, the tissue residue levels and health risk of trace elements (TEs) in N. phocaenoides from the PRE have been little studied. Eleven typical TEs distributed in skin, liver and kidney tissues were investigated from 25 specimens stranded along the PRE from 2007 to 2015 in the present study. It revealed that most TEs were highly accumulated in internal organs (liver and kidney), except for Zn with high residue levels in external skin. Compared with the TEs in prey items, the residue levels of Hg, Se, Zn, Cu, Cd and Cr in N. phocaenoides increased 4-618 times, indicating a potentially significant biomagnification. Sex-related differences of TE accumulation were not obvious, except for renal Mn, in which the females showed lower mean concentrations than males. Significantly positive correlations between body length and TE levels were found for Hg, Se and Cd. Results of the calculated risk quotients (RQ) suggested that the risks to N. phocaenoides from consumption of prey items were generally low, but further attentions should be paid to Cd, Cr, Cu, Hg and As due to the elevated RQ values. The concentrations of Hg, Cd and Se in the epidermis were positively correlated with the levels found in internal organs. Our investigation provides evidence to support the use of skin as one biomonitoring approach on Hg, Cd and Se contamination of internal tissues in this species. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dynamics in benthic community composition and influencing factors in an upwelling-exposed coral reef on the Pacific coast of Costa Rica

PubMed Central

Sánchez-Noguera, Celeste; Roth, Florian; Jiménez, Carlos; Rixen, Tim; Cortés, Jorge; Wild, Christian

2015-01-01

Seasonal upwelling at the northern Pacific coast of Costa Rica offers the opportunity to investigate the effects of pronounced changes in key water parameters on fine-scale dynamics of local coral reef communities. This study monitored benthic community composition at Matapalo reef (10.539°N, 85.766°W) by weekly observations of permanent benthic quadrats from April 2013 to April 2014. Monitoring was accompanied by surveys of herbivore abundance and biomass and measurements of water temperature and inorganic nutrient concentrations. Findings revealed that the reef-building corals Pocillopora spp. exhibited an exceptional rapid increase from 22 to 51% relative benthic cover. By contrast, turf algae cover decreased from 63 to 24%, resulting in a corresponding increase in crustose coralline algae cover. The macroalga Caulerpa sertularioides covered up to 15% of the reef in April 2013, disappeared after synchronized gamete release in May, and subsequently exhibited slow regrowth. Parallel monitoring of influencing factors suggest that C. sertularioides cover was mainly regulated by their reproductive cycle, while that of turf algae was likely controlled by high abundances of herbivores. Upwelling events in February and March 2014 decreased mean daily seawater temperatures by up to 7 °C and increased nutrient concentrations up to 5- (phosphate) and 16-fold (nitrate) compared to mean values during the rest of the year. Changes in benthic community composition did not appear to correspond to the strong environmental changes, but rather shifted from turf algae to hard coral dominance over the entire year of observation. The exceptional high dynamic over the annual observation period encourages further research on the adaptation potential of coral reefs to environmental variability. PMID:26623190

Influence of flooding and vegetation on carbon, nitrogen, and phosphorus dynamics in the pore water of a Spartina alterniflora salt marsh.

PubMed

Negrin, Vanesa L; Spetter, Carla V; Asteasuain, Raúl O; Perillo, Gerardo M E; Marcovecchio, Jorge E

2011-01-01

Four sites were selected in a salt marsh in the Bahia Blanca Estuary (Argentina): (1) low marsh (flooded by the tide twice daily) vegetated by S. alterniflora; (2) non-vegetated low marsh; (3) high marsh (flooded only in spring tides) vegetated by S. alterniflora; (4) non-vegetated high marsh. The pH and Eh were measured in sediments, while dissolved nutrients (ammonium, nitrate, nitrite and phosphate) and particulate organic matter (POM) were determined in pore water. pH (6.2-8.7) was only affected by vegetation in low areas. Eh (from -300 to 250 mV) was lower at low sites than at high ones; in the latter, the values were higher in the non-vegetated sediments. The POM concentration was greater in the high marsh than in the low marsh, with no effect of vegetation. Ammonium was the most abundant nitrogen nutrient species in pore water, except in the non-vegetated high marsh where nitrate concentration was higher. All nitrogen nutrients were affected by both flooding and vegetation. Phosphate was always present in pore water at all sites throughout the year and its concentration varied within narrow limits, with no effect of flooding and greater values always at non-vegetated sites. Our results showed that the variability of the pore water composition within the marsh is greater than the temporal variation, meaning that both tidal flooding and vegetation are important in the dynamics of nutrients and organic matter in the sediment pore water.

Deposition of chromium in aquatic ecosystem from effluents of handloom textile industries in Ranaghat-Fulia region of West Bengal, India.

PubMed

Sanyal, Tanmay; Kaviraj, Anilava; Saha, Subrata

2015-11-01

Accumulation of chromium (Cr) was determined in water, sediment, aquatic plants, invertebrates and fish in aquatic ecosystems receiving effluents from handloom textile industries in Ranaghat-Fulia region of West Bengal in India. Cr was determined in the samples by atomic absorption spectrophotometer and data were analyzed functionally by Genetic Algorithm to determine trend of depositions of Cr in the sediment and water. Area plot curve was used to represent accumulation of Cr in biota. The results indicate that the aquatic ecosystems receiving the effluents from handloom textile factories are heavily contaminated by Cr. The contamination is hardly reflected in the concentration of Cr in water, but sediment exhibits seasonal fluctuation in deposition of Cr, concentration reaching to as high as 451.0 μg g(-1) during the peak production period. There is a clear trend of gradual increase in the deposition of Cr in the sediment. Aquatic weed, insect and mollusk specimens collected from both closed water bodies (S1 & S2) and riverine resources (S3 & S4) showed high rate of accumulation of Cr. Maximum concentration of Cr was detected in roots of aquatic weeds (877.5 μg g(-1)). Fish specimens collected from the polluted sites (S3 & S4) of river Churni showed moderate to high concentration of Cr in different tissues. Maximum concentration was detected in the liver of Glossogobius giuris (679.7 μg g(-1)) during monsoon followed by gill of Mystus bleekeri (190.0 μg g(-1)) and gut of G. giuris (123.7 μg g(-1)) during summer. Eutropiichthys vacha showed moderately high concentration of Cr in different tissues (65-99 μg g(-1)) while Puntius sarana showed relatively low concentration of Cr (below detection limit to 18.0 μg g(-1)) in different tissues except in gill (64.4 μg g(-1)).

Deposition of chromium in aquatic ecosystem from effluents of handloom textile industries in Ranaghat–Fulia region of West Bengal, India

PubMed Central

Sanyal, Tanmay; Kaviraj, Anilava; Saha, Subrata

2014-01-01

Accumulation of chromium (Cr) was determined in water, sediment, aquatic plants, invertebrates and fish in aquatic ecosystems receiving effluents from handloom textile industries in Ranaghat–Fulia region of West Bengal in India. Cr was determined in the samples by atomic absorption spectrophotometer and data were analyzed functionally by Genetic Algorithm to determine trend of depositions of Cr in the sediment and water. Area plot curve was used to represent accumulation of Cr in biota. The results indicate that the aquatic ecosystems receiving the effluents from handloom textile factories are heavily contaminated by Cr. The contamination is hardly reflected in the concentration of Cr in water, but sediment exhibits seasonal fluctuation in deposition of Cr, concentration reaching to as high as 451.0 μg g−1 during the peak production period. There is a clear trend of gradual increase in the deposition of Cr in the sediment. Aquatic weed, insect and mollusk specimens collected from both closed water bodies (S1 & S2) and riverine resources (S3 & S4) showed high rate of accumulation of Cr. Maximum concentration of Cr was detected in roots of aquatic weeds (877.5 μg g−1). Fish specimens collected from the polluted sites (S3 & S4) of river Churni showed moderate to high concentration of Cr in different tissues. Maximum concentration was detected in the liver of Glossogobius giuris (679.7 μg g−1) during monsoon followed by gill of Mystus bleekeri (190.0 μg g−1) and gut of G. giuris (123.7 μg g−1) during summer. Eutropiichthys vacha showed moderately high concentration of Cr in different tissues (65–99 μg g−1) while Puntius sarana showed relatively low concentration of Cr (below detection limit to 18.0 μg g−1) in different tissues except in gill (64.4 μg g−1). PMID:26644938

Hormonal status and fluid electrolyte metabolism in motion sickness

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

Grigoriev, A.I.; Nichiporuk, I.A.; Yasnetsov, V.V.

1988-04-01

In the first experimental series, 10 healthy male test subjects with a high susceptibility to motion sickness showed a significant increase of ACTH, cortisol, STH, prolactin, ADH, aldosterone concentrations, and plasma renin activity after vestibular tests. The 10 subjects with a moderate susceptibility exhibited a still higher increase of the hormones, except plasma renin. The 8 test subjects with a low susceptibility displayed a considerable increase in ACTH, cortisol, and STH after vestibular stimulation. In the second experimental series, the increase of STH, cortisol, ADH, aldosterone and renin occurred immediately after rotation in the moderate susceptibility subjects and an hourmore » after exposure in the high susceptibility subjects. This may be indicative of specific immediate adaptation mechanisms or excitation transfer in the CNS in high susceptibility persons. In the third experimental animal series, the permeability of the blood-brain barrier for /sup 125/I and IgG increased after rotation. Greater concentrations of potassium, chloride, and urea in CSF are suggestive of an inhibition process activation in the CNS and, probably, of an active urea transport by the vascular plexus epithelium which maintains constant osmotic pressure of cerebral extracellular fluid and prevents hyper-hydration of CNS neurons.« less

Mycotoxins transmitted into beer from contaminated grains during brewing.

PubMed

Scott, P M

1996-01-01

Studies with aflatoxin B1, ochratoxin A, zearalenone, deoxynivalenol, and fumonisins B1 and B2 added at various stages of the brewing process show that these mycotoxins (or metabolites) may be transmitted from contaminated grains into beer. Citrinin does not survive the mashing step. Mycotoxins in beer could originate from the malted grain or from adjuncts. Although high incidences and concentrations of aflatoxins and zearalenone have been found in local beers brewed in Africa, aflatoxins have not been detected in European beers. Zearalenone and alpha- or beta-zearalenol (the metabolite likely to occur) have not been found in Canadian and European beers, except for one sample analyzed by thin-layer chromatography only. Ochratoxin A rarely has been detected at > 1 ng/mL in beer; liquid chromatographic methods with a 0.05-0.1 ng/mL detection limit, however, have shown moderately high incidences of trace levels. Deoxynivalenol, which survives the brewing process, has been found with high incidence in Canadian and European beers, with concentration of > 200 ng/mL reported in several German beers. Fumonisins B1 and B2 occur to a limited extent in beer.

Non conventional biological treatment based on Trametes versicolor for the elimination of recalcitrant anticancer drugs in hospital wastewater.

PubMed

Ferrando-Climent, Laura; Cruz-Morató, Carles; Marco-Urrea, Ernest; Vicent, Teresa; Sarrà, Montserrat; Rodriguez-Mozaz, Sara; Barceló, Damià

2015-10-01

This work presents a study about the elimination of anticancer drugs, a group of pollutants considered recalcitrant during conventional activated sludge wastewater treatment, using a biological treatment based on the fungus Trametes versicolor. A 10-L fluidized bed bioreactor inoculated with this fungus was set up in order to evaluate the removal of 10 selected anticancer drugs in real hospital wastewater. Almost all the tested anticancer drugs were completely removed from the wastewater at the end of the batch experiment (8 days) with the exception of Ifosfamide and Tamoxifen. These two recalcitrant compounds, together with Cyclophosphamide, were selected for further studies to test their degradability by T. versicolor under optimal growth conditions. Cyclophosphamide and Ifosfamide were inalterable during batch experiments both at high and low concentration, whereas Tamoxifen exhibited a decrease in its concentration along the treatment. Two positional isomers of a hydroxylated form of Tamoxifen were identified during this experiment using a high resolution mass spectrometry based on ultra-high performance chromatography coupled to an Orbitrap detector (LTQ-Velos Orbitrap). Finally the identified transformation products of Tamoxifen were monitored in the bioreactor run with real hospital wastewater. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of quality-control data collected by the U.S. Geological Survey for routine water-quality activities at the Idaho National Laboratory and vicinity, southeastern Idaho, 2002-08

USGS Publications Warehouse

Rattray, Gordon W.

2014-01-01

Quality-control (QC) samples were collected from 2002 through 2008 by the U.S. Geological Survey, in cooperation with the U.S. Department of Energy, to ensure data robustness by documenting the variability and bias of water-quality data collected at surface-water and groundwater sites at and near the Idaho National Laboratory. QC samples consisted of 139 replicates and 22 blanks (approximately 11 percent of the number of environmental samples collected). Measurements from replicates were used to estimate variability (from field and laboratory procedures and sample heterogeneity), as reproducibility and reliability, of water-quality measurements of radiochemical, inorganic, and organic constituents. Measurements from blanks were used to estimate the potential contamination bias of selected radiochemical and inorganic constituents in water-quality samples, with an emphasis on identifying any cross contamination of samples collected with portable sampling equipment. The reproducibility of water-quality measurements was estimated with calculations of normalized absolute difference for radiochemical constituents and relative standard deviation (RSD) for inorganic and organic constituents. The reliability of water-quality measurements was estimated with pooled RSDs for all constituents. Reproducibility was acceptable for all constituents except dissolved aluminum and total organic carbon. Pooled RSDs were equal to or less than 14 percent for all constituents except for total organic carbon, which had pooled RSDs of 70 percent for the low concentration range and 4.4 percent for the high concentration range. Source-solution and equipment blanks were measured for concentrations of tritium, strontium-90, cesium-137, sodium, chloride, sulfate, and dissolved chromium. Field blanks were measured for the concentration of iodide. No detectable concentrations were measured from the blanks except for strontium-90 in one source solution and one equipment blank collected in September and October 2004, respectively. The detectable concentrations of strontium-90 in the blanks probably were from a small source of strontium-90 contamination or large measurement variability, or both. Order statistics and the binomial probability distribution were used to estimate the magnitude and extent of any potential contamination bias of tritium, strontium-90, cesium-137, sodium, chloride, sulfate, dissolved chromium, and iodide in water-quality samples. These statistical methods indicated that, with (1) 87 percent confidence, contamination bias of cesium-137 and sodium in 60 percent of water-quality samples was less than the minimum detectable concentration or reporting level; (2) 92‒94 percent confidence, contamination bias of tritium, strontium-90, chloride, sulfate, and dissolved chromium in 70 percent of water-quality samples was less than the minimum detectable concentration or reporting level; and (3) 75 percent confidence, contamination bias of iodide in 50 percent of water-quality samples was less than the reporting level for iodide. These results support the conclusion that contamination bias of water-quality samples from sample processing, storage, shipping, and analysis was insignificant and that cross-contamination of perched groundwater samples collected with bailers during 2002–08 was insignificant.

Different variations of tissue B-group vitamin concentrations in short- and long-term starved rats.

PubMed

Moriya, Aya; Fukuwatari, Tsutomu; Sano, Mitsue; Shibata, Katsumi

2012-01-01

Prolonged starvation changes energy metabolism; therefore, the metabolic response to starvation is divided into three phases according to changes in glucose, lipid and protein utilisation. B-group vitamins are involved in energy metabolism via metabolism of carbohydrates, fatty acids and amino acids. To determine how changes in energy metabolism alter B-group vitamin concentrations during starvation, we measured the concentration of eight kinds of B-group vitamins daily in rat blood, urine and in nine tissues including cerebrum, heart, lung, stomach, kidney, liver, spleen, testis and skeletal muscle during 8 d of starvation. Vitamin B1, vitamin B6, pantothenic acid, folate and biotin concentrations in the blood reduced after 6 or 8 d of starvation, and other vitamins did not change. Urinary excretion was decreased during starvation for all B-group vitamins except pantothenic acid and biotin. Less variation in B-group vitamin concentrations was found in the cerebrum and spleen. Concentrations of vitamin B1, vitamin B6, nicotinamide and pantothenic acid increased in the liver. The skeletal muscle and stomach showed reduced concentrations of five vitamins including vitamin B1, vitamin B2, vitamin B6, pantothenic acid and folate. Concentrations of two or three vitamins decreased in the kidney, testis and heart, and these changes showed different patterns in each tissue and for each vitamin. The concentration of pantothenic acid rapidly decreased in the heart, stomach, kidney and testis, whereas concentrations of nicotinamide were stable in all tissues except the liver. Different variations in B-group vitamin concentrations in the tissues of starved rats were found. The present findings will lead to a suitable supplementation of vitamins for the prevention of the re-feeding syndrome.

Chemical analysis and potential endocrine activities of aluminium coatings intended to be in contact with cosmetic water.

PubMed

Bou-Maroun, Elias; Dahbi, Laurence; Gomez-Berrada, Marie-Pierre; Pierre, Philippine; Rakotomalala, Sandrine; Ferret, Pierre-Jacques; Chagnon, Marie-Christine

2017-10-25

The objective of the work was to check the presence of Non-Intended Added Substances (NIAS) with hormonal activities in aluminium coatings extracts coded: AA, BBF, MC and RR, furnished by four different suppliers. Water samples were prepared at room temperature or at 40°C for three months to verify the storage effect on the coatings. Solid phase extraction was used to concentrate and to extract coating substances. Hormonal activities were checked in vitro using reporter gene bioassays. Except BBF, all extracts induced a weak but significant estrogenic agonist activity in the human cell line. Using an estrogenic antagonist (ICI-182, 780), the answer was demonstrated specific in the bioassay. RR was the only extract to induce a concentration dependent anti-androgenic response in the MDA-KB2 cell line. Analysis performed using GC-MS and HPLC-MS detected 12 substances in most of the extracts. 8 NIAS were present. Among them, 4 were identified with certainty: HMBT, BGA, DCU and BPA. Estrogenic potency was BPA>DCU>BGA>HMBT. HMBT was also anti-androgenic at high concentration. Combining chemical analysis and bioassays data, we demonstrated that in the RR and the RR40 extracts, the observed estrogenic response was mainly due to BPA, the anti-androgenic activity of RR could be due to a synergism between HMBT and BPA. For MC and AA, estrogenic responses appear to be due to the presence of DCU. Except BBF, storage conditions tended to increase estrogenic activities in all extracts. However, in term of risk assessment, activities observed were negligible. This work demonstrated that sensitive bioassays are pertinent tools in complement to chemical analysis to monitor and check the presence of NIAS with hormonal activity in coating extracts. Copyright © 2017 Elsevier B.V. All rights reserved.

Heavy metals pollution levels and children health risk assessment of Yerevan kindergartens soils.

PubMed

Tepanosyan, Gevorg; Maghakyan, Nairuhi; Sahakyan, Lilit; Saghatelyan, Armen

2017-08-01

Children, the most vulnerable urban population group, are exceptionally sensitive to polluted environments, particularly urban soils, which can lead to adverse health effects upon exposure. In this study, the total concentrations of Ag, As, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Ti, V, and Zn were determined in 111 topsoil samples collected from kindergartens in Yerevan. The objectives of this study were to evaluate heavy metal pollution levels of kindergarten's soils in Yerevan, compare with national legal and international requirements on heavy metal contents in kindergarten soil, and assess related child health risk. Multivariate geostatistical analyses suggested that the concentrations of Ag, As, Ba, Cd, Cu, Hg, Mo, Pb, and Zn observed in the kindergarten's topsoil may have originated from anthropogenic sources, while Co, Cr, Fe, Mn, Ni, Ti, and V mostly come from natural sources. According to the Summary pollution index (Zc), 102 kindergartens belong to the low pollution level, 7 to the moderate and only 2 to the high level of pollution. Summary concentration index (SCI) showed that 109 kindergartens were in the allowable level, while 2 featured in the low level of pollution. The health risk assessment showed that in all kindergartens except for seven, non-carcinogenic risk for children was detected (HI>1), while carcinogenic risk from arsenic belongs to the very low (allowable) level. Cr and multi-element carcinogenic risk (RI) exceeded the safety level (1.0E- 06) in all kindergartens and showed that the potential of developing cancer, albeit small, does exist. Therefore, city's kindergartens require necessary remedial actions to eliminate or reduce soil pollution and heavy metal-induced health risks. Copyright © 2017 Elsevier Inc. All rights reserved.

Nitrate uptake and utilization is modulated by exogenous gamma-aminobutyric acid in Arabidopsis thaliana seedlings.

PubMed

Barbosa, Jose M; Singh, Narendra K; Cherry, Joe H; Locy, Robert D

2010-06-01

Exogenously applied GABA modulates root growth by inhibition of root elongation when seedlings were grown in vitro on full-strength Murashige and Skoog (MS) salts, but root elongation was stimulated when seedlings were grown on 1/8 strength MS salts. When the concentration of single ions in MS salts was individually varied, the control of growth between inhibition and stimulation was found to be related to the level of nitrate (NO(3)(-)) in the growth medium. At NO(3)(-) concentrations below 40 mM (full-strength MS salts level), root growth was stimulated by the addition of GABA to the growth medium; whereas at concentrations above 40 mM NO(3)(-), the addition of GABA to the growth medium inhibited root elongation. GABA promoted NO(3)(-) uptake at low NO(3)(-), while GABA inhibited NO(3)(-) uptake at high NO(3)(-). Activities of several enzymes involved in nitrogen and carbon metabolism including nitrate reductase (NR), glutamine synthetase (GS), glutamate synthase (NADH-GOGAT), NADP-dependent isocitrate dehydrogenase (NADP-ICDH), and phosphoenol pyruvate carboxylase (PEPCase) were regulated by GABA in the growth medium. Supplementing 1/8 strength MS medium with 50 mM GABA enhanced the activities of all of the above enzymes except ICDH activities in root tissues. However, at full-strength MS, GABA showed no inhibitory effect on the activities of these enzymes, except on GS in both root and shoot tissues, and PEPCase activity in shoot tissues. Exogenous GABA increased the amount of NR protein rather than its activation status in the tissues. This study shows that GABA affects the growth of Arabidopsis, possibly by acting as a signaling molecule, modulating the activity of enzymes involved in primary nitrogen metabolism and nitrate uptake.

Contaminant risks from biosolids land application: contemporary organic contaminant levels in digested sewage sludge from five treatment plants in Greater Vancouver, British Columbia.

PubMed

Bright, D A; Healey, N

2003-01-01

This study examines the potential for environmental risks due to organic contaminants at sewage sludge application sites, and documents metals and various potential organic contaminants (volatile organics, chlorinated pesticides, PCBs, dioxins/furans, extractable petroleum hydrocarbons, PAHs, phenols, and others) in current production biosolids from five wastewater treatment plants (WWTPs) within the Greater Vancouver Regional District (GVRD). There has been greater focus in Europe, North America and elsewhere on metals accumulation in biosolids-amended soil than on organic substances, with the exception of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans. Another objective, therefore, was to evaluate the extent to which management of biosolids re-use based on metal/metalloid levels coincidentally minimizes environmental risks from organic contaminants. Historical-use contaminants such as chlorophenols, PCBs, and chlorinated pesticides were not detected at environmentally relevant concentrations in any of the 36 fresh biosolids samples, and appear to have virtually eliminated from sanitary collection system inputs. The few organic contaminants found in freshly produced biosolids samples that exhibited high concentrations relative to British Columbia and Canadian soil quality benchmarks included p-cresol, phenol, phenanthrene, pyrene, naphthalene, and heavy extractable petroleum hydrocarbons (HEPHs--nCl9-C34 effective carbon chain length). It was concluded that, with the exception of these petroleum hydrocarbon constituents or their microbial metabolites, the mixing of biosolids with uncontaminated soils during land application and based on the known metal concentrations in biosolids from the Greater Vancouver WWTPs investigated provides adequate protection against the environmental risks associated with organic substances such as dioxins and furans, phthalate esters, or volatile organics. Unlike many other organic contaminants, the concentrations of petroleum hydrocarbon derived substances in biosolids has not decreased within the last decade or more in the WWTPs studied, and--unlike persistent chlorinated compounds--the associated PAHs and other hydrocarbon constituents merit careful consideration, especially in the context of repeated land-application of biosolid.

HIV-infected children living in Central Africa have low persistence of antibodies to vaccines used in the Expanded Program on Immunization.

PubMed

Tejiokem, Mathurin C; Gouandjika, Ionela; Béniguel, Lydie; Zanga, Marie-Claire Endegue; Tene, Gilbert; Gody, Jean C; Njamkepo, Elisabeth; Kfutwah, Anfumbom; Penda, Ida; Bilong, Catherine; Rousset, Dominique; Pouillot, Régis; Tangy, Frédéric; Baril, Laurence

2007-12-05

The Expanded Program on Immunization (EPI) is the most cost-effective measures to control vaccine-preventable diseases. Currently, the EPI schedule is similar for HIV-infected children; the introduction of antiretroviral therapy (ART) should considerably prolong their life expectancy. To evaluate the persistence of antibodies to the EPI vaccines in HIV-infected and HIV-exposed uninfected children who previously received these vaccines in routine clinical practice, we conducted a cross-sectional study of children, aged 18 to 36 months, born to HIV-infected mothers and living in Central Africa. We tested blood samples for antibodies to the combined diphtheria, tetanus, and whole-cell pertussis (DTwP), the measles and the oral polio (OPV) vaccines. We enrolled 51 HIV-infected children of whom 33 were receiving ART, and 78 HIV-uninfected children born to HIV-infected women. A lower proportion of HIV-infected children than uninfected children had antibodies to the tested antigens with the exception of the OPV types 1 and 2. This difference was substantial for the measles vaccine (20% of the HIV-infected children and 56% of the HIV-exposed uninfected children, p<0.0001). We observed a high risk of low antibody levels for all EPI vaccines, except OPV types 1 and 2, in HIV-infected children with severe immunodeficiency (CD4(+) T cells <25%). Children were examined at a time when their antibody concentrations to EPI vaccines would have still not undergone significant decay. However, we showed that the antibody concentrations were lowered in HIV-infected children. Moreover, antibody concentration after a single dose of the measles vaccine was substantially lower than expected, particularly low in HIV-infected children with low CD4(+) T cell counts. This study supports the need for a second dose of the measles vaccine and for a booster dose of the DTwP and OPV vaccines to maintain the antibody concentrations in HIV-infected and HIV-exposed uninfected children.

Characterization and treatment of dissolved organic matter from oilfield produced waters.

PubMed

Wang, Xiaojing; Goual, Lamia; Colberg, Patricia J S

2012-05-30

Dissolved organic matter (DOM) has been studied intensively in streams, lakes and oceans due to its role in the global carbon cycle and because it is a precursor of carcinogenic disinfection by-products in drinking water; however, relatively little research has been conducted on DOM in oilfield produced waters. In this study, recovery of DOM from two oilfield produced waters was relatively low (~34%), possibly due to the presence of high concentrations of volatile organic compounds (VOCs). A van Krevelen diagram of the extracted DOM suggested the presence of high concentrations of lipids, lignin, and proteins, but low concentrations of condensed hydrocarbons. Most of the compounds in the oilfield DOM contained sulfur in their structures. Fourier transform infrared (FTIR) spectra indicated the presence of methyl groups, amides, carboxylic acids, and aromatic compounds, which is in agreement with results of Fourier transform ion cyclotron resonance (FT-ICR) analysis. Qualitatively, DOM in oilfield produced waters is similar to that reported in oceans and freshwater, except that it contains much more sulfur and is less aromatic. Treatment studies conducted in a fluidized bed reactor suggested that volatilization of organics may be a more important mechanism of DOM removal than microbial degradation. Copyright © 2012 Elsevier B.V. All rights reserved.

Long-term limnological data from the larger lakes of Yellowstone National Park, Wyoming, USA

USGS Publications Warehouse

Theriot, E.C.; Fritz, S.C.; Gresswell, Robert E.

1997-01-01

Long-term limnological data from the four largest lakes in Yellowstone National Park (Yellowstone, Lewis, Shoshone, Heart) are used to characterize their limnology and patterns of temporal and spatial variability. Heart Lake has distinctively high concentrations of dissolved materials, apparently reflecting high thermal inputs. Shoshone and Lewis lakes have the highest total SiO2 concentrations (averaging over 23.5 mg L-1), apparently as a result of the rhyolitic drainage basins. Within Yellowstone Lake spatial variability is low and ephemeral for most measured variables, except that the Southeast Arm has lower average Na concentrations. Seasonal variation is evident for Secchi transparency, pH, and total-SiO2 and probably reflects seasonal changes in phytoplankton biomass and productivity. Total dissolved solids (TDS) and total-SiO2 generally show a gradual decline from the mid-1970s through mid-1980s, followed by a sharp increase. Ratios of Kjeldahl-N to total-PO4 (KN:TP) suggest that the lakes, especially Shoshone, are often nitrogen limited. Kjeldahl-N is positively correlated with winter precipitation, but TP and total-SiO2 are counterintuitively negatively correlated with precipitation. We speculate that increased winter precipitation, rather than watershed fires, increases N-loading which, in turn, leads to increased demand for TP and total SiO2.

Occupational exposure to coal tar pitch volatiles, benzo/a/pyrene and dust in tyre production.

PubMed

Rogaczewska, T; Ligocka, D

1994-01-01

Occupational exposure to coal tar pitch volatiles (CTPVs), benzo/a/pyrene (BaP) and dust was evaluated by means of individual measurements carried out in 80 workers and by stationary measurements on 16 work-posts in two divisions of the tyre producing plant. Dust and coal tar pitch volatiles concentrations in the air were determinated by the gravimetric method, measured, in the case of CPTVs, benzene-soluble fraction (BSF) with ultrasonic extraction. Benzo/a/pyrene analysis was performed using high performance liquid chromato-graphy (HPLC) with a spectrofluorimetric detector. It was found that nearly all personal sampling results for BaP were within the range < 4 divided by 142 ng/m3, except for the exposure of workers employed at weighing the raw materials (3,470-6,060 ng/m3) in the Semiproducts Division. Attention should be paid to the recorded CTPVs concentrations (benzene solubles). About 56% of the Vulcanizing Division workers and about 90% of the Semiproducts Division workers were exposed to these substances at concentrations of over 0.2 mg/m3 (hygienic standard for benzene solubles in USA). Exposure to dust (of high respirable fraction percentage > 90%) which exceeded the admissible value (4 mg/m3) was found mainly only in the workers of the Semiproducts Division at some work-posts.

Phytoextraction of heavy metal polluted soils using Sedum plumbizincicola inoculated with metal mobilizing Phyllobacterium myrsinacearum RC6b.

PubMed

Ma, Ying; Rajkumar, Mani; Luo, Yongming; Freitas, Helena

2013-10-01

The aim of this study was to investigate the effects of metal mobilizing plant-growth beneficial bacterium Phyllobacterium myrsinacearum RC6b on plant growth and Cd, Zn and Pb uptake by Sedum plumbizincicola under laboratory conditions. Among a collection of metal-resistant bacteria, P. myrsinacearum RC6b was specifically chosen as a most favorable metal mobilizer based on its capability of mobilizing high concentrations of Cd, Zn and Pb in soils. P. myrsinacearum RC6b exhibited a high degree of resistance to Cd (350 mg L(-1)), Zn (1000 mg L(-1)) and Pb (1200 mg L(-1)). Furthermore, P. myrsinacearum RC6b showed multiple plant growth beneficial features including the production of 1-aminocyclopropane-1-carboxylic acid deaminase, indole-3-acetic acid, siderophore and solubilization of insoluble phosphate. Inoculation of P. myrsinacearum RC6b significantly increased S. plumbizincicola growth and organ metal concentrations except Pb, which concentration was lower in root and stem of inoculated plants. The results suggest that the metal mobilizing P. myrsinacearum RC6b could be used as an effective inoculant for the improvement of phytoremediation in multi-metal polluted soils. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects of food availability on serum insulin and lipid concentrations in free-ranging baboons.

PubMed

Kemnitz, Joseph W; Sapolsky, Robert M; Altmann, Jeanne; Muruthi, Philip; Mott, Glen E; Stefanick, Marcia L

2002-05-01

The relationship between food availability and metabolic physiology was studied in groups of free-ranging baboons (Papio spp.) living in the Amboseli National Park and the Masai Mara National Reserve of Kenya. Three groups subsisted entirely on natural forage, while two other groups lived near tourist facilities and often consumed food wastes from these lodges. The refuse provided a very accessible food source with relatively high caloric density. Consumption of the refuse was associated with reduced locomotion. Sexually mature individuals from all five groups were sedated surreptitiously in the early morning and blood samples were collected. Compared to animals foraging exclusively in the wild, animals that supplemented their diet with the refuse items had two- to threefold elevations in serum insulin concentrations, as well as increased total cholesterol (C), HDL-C, and VLDL+LDL-C levels. No sex differences in physiological measures were observed except in body mass. Elevated serum insulin, and cholesterol and lipoprotein concentrations influence the development of cardiovascular disease and have been shown to be subject to dietary manipulation and exercise under controlled conditions. The present results suggest potentially deleterious effects of a highly accessible, calorically dense food source, and associated reduction of physical activity for baboons living in an otherwise natural environment. Copyright 2002 Wiley-Liss, Inc.

The Curious Case of the OZ439 Mesylate Salt: An Amphiphilic Antimalarial Drug with Diverse Solution and Solid State Structures.

PubMed

Clulow, Andrew J; Salim, Malinda; Hawley, Adrian; Gilbert, Elliot P; Boyd, Ben J

2018-05-07

Efforts to develop orally administered drugs tend to place an exceptional focus on aqueous solubility as this is an essential criterion for their absorption in the gastrointestinal tract. In this work we examine the solid state behavior and solubility of OZ439, a promising single-dose cure for malaria being developed as the highly water-soluble mesylate salt. The aqueous phase behavior of the OZ439 mesylate salt was determined using a combination of small angle neutron and X-ray scattering (SANS and SAXS, respectively). It was found that this salt has low solubility at low concentrations with the drug largely precipitated in free base aggregates. However, with increasing concentration these crystalline aggregates were observed to dissociate into cationic micelles and lamellar phases, effectively increasing the dissolved drug concentration. It was also found that the dissolved OZ439 spontaneously precipitated in the presence of biologically relevant anions, which we attribute to the high lattice energies of most of the salt forms of the drug. These findings show that aqueous solubility is not always what it seems in the context of amphiphilic drug molecules and highlights that its use as the principal metric in selecting drug candidates for development can be perilous.

Pure-rotational spectrometry: a vintage analytical method applied to modern breath analysis.

PubMed

Hrubesh, Lawrence W; Droege, Michael W

2013-09-01

Pure-rotational spectrometry (PRS) is an established method, typically used to study structures and properties of polar gas-phase molecules, including isotopic and isomeric varieties. PRS has also been used as an analytical tool where it is particularly well suited for detecting or monitoring low-molecular-weight species that are found in exhaled breath. PRS is principally notable for its ultra-high spectral resolution which leads to exceptional specificity to identify molecular compounds in complex mixtures. Recent developments using carbon aerogel for pre-concentrating polar molecules from air samples have extended the sensitivity of PRS into the part-per-billion range. In this paper we describe the principles of PRS and show how it may be configured in several different modes for breath analysis. We discuss the pre-concentration concept and demonstrate its use with the PRS analyzer for alcohols and ammonia sampled directly from the breath.

Determination of the electron-capture coefficients and the concentration of free electrons in GaN from time-resolved photoluminescence

PubMed Central

Reshchikov, M. A.; McNamara, J. D.; Toporkov, M.; Avrutin, V.; Morkoç, H.; Usikov, A.; Helava, H.; Makarov, Yu.

2016-01-01

Point defects in high-purity GaN layers grown by hydride vapor phase epitaxy are studied by steady-state and time-resolved photoluminescence (PL). The electron-capture coefficients for defects responsible for the dominant defect-related PL bands in this material are found. The capture coefficients for all the defects, except for the green luminescence (GL1) band, are independent of temperature. The electron-capture coefficient for the GL1 band significantly changes with temperature because the GL1 band is caused by an internal transition in the related defect, involving an excited state acting as a giant trap for electrons. By using the determined electron-capture coefficients, the concentration of free electrons can be found at different temperatures by a contactless method. A new classification system is suggested for defect-related PL bands in undoped GaN. PMID:27901025

Factors regulating ozone over the United States and its export to the global atmosphere

NASA Technical Reports Server (NTRS)

Jacob, Daniel J.; Logan, Jennifer A.; Gardner, Geraldine M.; Yevich, Rose M.; Spivakovsky, Clarisa M.; Wofsy, Steven C.; Sillman, Sanford; Prather, Michael J.

1993-01-01

Attention is given to the factors regulating summertime O3 over the U.S. and its export to the global atmosphere, which are examined via a 3-mo simulation involving a continental-scale 3D photochemical model. It is found that reducing NO(x) emissions by 50 percent from 1985 levels would decrease rural O3 concentrations over the eastern U.S. by about 15 percent under almost all meteorological conditions, while reducing anthropogenic hydrocarbon emissions by 50 percent would have less than a 4 percent effect except in the largest urban plumes. The correlation between O3 concentrations and temperature observed at eastern U.S. sites is attributed in part to the association of high temperatures with regional stagnation, and in part to an actual dependence of O3 production on temperature driven primarily by conversion of NO(x) to PAN.

Analytical study of endocrine-disrupting chemicals in leachate treatment process of municipal solid waste (MSW) landfill sites.

PubMed

Asakura, Hiroshi; Matsuto, Toshihiko; Tanaka, Nobutoshi

2007-01-01

Influent and processed water were sampled at different points in the leachate treatment facilities of five municipal solid waste (MSW) landfill sites. Then, the concentrations of endocrine-disrupting chemicals (EDCs), namely, alkylphenols (APs), bisphenol A (BPA), phthalic acid esters (PAEs) and organotin compounds (OTs), in the treated leachate samples were determined and the behavior of the EDCs in the treatment processes was discussed. The concentrations of APs were as low as those in surface waters, and no OTs were detected (detection limit: 0.01 microg/L). Meanwhile, diethylhexyl phthalate (DEHP), which was the most abundant of the four substances measured as PAEs, and BPA were found in all of the influent samples. BPA was considerably degraded by aeration, except when the water temperature was low and the total organic carbon (TOC) was high. By contrast, aeration, biological treatment, and coagulation/sedimentation removed only a small amount of DEHP.

Phytoremediation of Heavy Metals in Contaminated Water and Soil Using Miscanthus sp. Goedae-Uksae 1.

PubMed

Bang, Jihye; Kamala-Kannan, Seralathan; Lee, Kui-Jae; Cho, Min; Kim, Chang-Hwan; Kim, Young-Jin; Bae, Jong-Hyang; Kim, Kyong-Ho; Myung, Hyun; Oh, Byung-Taek

2015-01-01

The aim of this study is to characterize the heavy metal phytoremediation potential of Miscanthus sp. Goedae-Uksae 1, a hybrid, perennial, bio-energy crop developed in South Korea. Six different metals (As, Cu, Pb, Ni, Cd, and Zn) were used for the study. The hybrid grass effectively absorbed all the metals from contaminated soil. The maximum removal was observed for As (97.7%), and minimum removal was observed for Zn (42.9%). Similarly, Goedae-Uksae 1 absorbed all the metals from contaminated water except As. Cd, Pb, and Zn were completely (100%) removed from contaminated water samples. Generally, the concentration of metals in roots was several folds higher than in shoots. Initial concentration of metals highly influenced the phytoremediation rate. The results of the bioconcentration factor, translocation factor, and enrichment coefficient tests indicate that Goedae-Uksae 1 could be used for phytoremediation in a marginally contaminated ecosystem.

Chemical composition of Martian fines

NASA Technical Reports Server (NTRS)

Clark, B. C.; Baird, A. K.; Weldon, R. J.; Tsusaki, D. M.; Schnabel, L.; Candelaria, M. P.

1982-01-01

Of the 21 samples acquired for the Viking X-ray fluorescence spectrometer, 17 were analyzed to high precision. Compared to typical terrestrial continental soils and lunar mare fines, the Martian fines are lower in Al, higher in Fe, and much higher in S and Cl concentrations. Protected fines at the two lander sites are almost indistinguishable, but concentration of the element S is somewhat higher at Utopia. Duricrust fragments, successfully acquired only at the Chryse site, invariably contained about 50% higher S than fines. No elements correlate positively with S, except Cl and possibly Mg. A sympathetic variation is found among the triad Si, Al, Ca; positive correlation occurs between Ti and Fe. Sample variabilities are as great within a few meters as between lander locations (4500 km apart), implying the existence of a universal Martian regolith component of constant average composition. The nature of the source materials for the regolith fines must be mafic to ultramafic.

Patterns of maternal yolk hormones in eastern screech owl eggs (Megascops asio)

USGS Publications Warehouse

Hahn, D. Caldwell

2011-01-01

Owl clutches typically hatch asynchronously, and brood size hierarchies develop. In this study, we describe intra-clutch variation of testosterone, androstenedione, estradiol, and corticosterone in Eastern screech owl egg yolks. In order to assess whether these hormones may have originated in the follicle, we also characterize variation of testosterone, androstenedione, and corticosterone within the exterior, intermediate, and interior regions of the yolk. Concentrations of testosterone and androstenedione were distributed relatively evenly across egg lay order with the exception of first-laid eggs that had significantly lower concentrations of both androgens than eggs later in the laying sequence. Corticosterone and estradiol did not vary with laying order. Our results suggest that when food is abundant, yolk hormones are deposited in patterns that minimize sibling differences except to reduce dominance by the first-hatching chick. Testosterone and androstenedione concentrations varied throughout the yolk, while corticosterone was evenly distributed throughout the yolk. This supports a follicular origin for both yolk androgens, and an adrenal origin for yolk corticosterone.

Cypermethrin and lambda-cyhalothrin induced in vivo alterations in nucleic acids and protein contents in a freshwater catfish, Clarias batrachus (Linnaeus; Family-Clariidae).

PubMed

Kumar, Amit; Sharma, Bechan; Pandey, Ravi S

2009-08-01

The fresh water fish, Clarias batrachus, were exposed to sub-acute concentrations of cypermethrin and lambda-cyhalothrin for 96 h to assess their impact on the levels of nucleic acids and protein in different organs of fish. DNA content was found almost unchanged with a single exception of liver, which showed significant increment in the levels of DNA in response to the separate treatments of both compounds. Both RNA and protein contents declined in brain, liver, and muscle while sharp increase was observed in gills. However, in kidney, RNA contents depicted significant enhancement only at higher concentrations, with initial decline at lower concentrations. The trends of alterations in RNA/DNA and protein/DNA ratios were quite similar to the corresponding results explained above for RNA and protein. The results clearly indicated that both of these pyrethroids exerted their effects at transcriptional and translational levels while DNA synthesis was found to be unaffected by these compounds with an exception of liver.

Correlation Of Giant Nuclei With Cloud Droplet Concentration

NASA Astrophysics Data System (ADS)

Jha, V.; Hudson, J. G.; Noble, S.

2011-12-01

The effect of giant nuclei (GN; larger than 1 micrometer particles produced by wind on the ocean surface) on warm rain has been debated for decades. During RICO (Rain in Cumulus over the Ocean) Hudson et al. (2011) found a negative correlation (R) between CCN concentrations at 1% supersaturation (S) and large cloud droplet concentrations (Fig. 1A). This reversal from positive R for CCN with total (or small) cloud droplet concentrations (left side of Fig. 1A) was explained by the greater competition for condensate, which thus limits droplet sizes when CCN concentrations are higher. The negative R increased in magnitude with altitude, and the droplet size where the maximum negative R occurred increased with altitude (Fig. 1A). However, at all altitudes this negative R decreased in magnitude for even larger cloud and drizzle drops (right side of Fig. 1A except highest altitude). The decrease in magnitude of the negative R was greater for increasing drop sizes at higher altitudes. Thus, at the higher altitudes, R for CCN with large drizzle drops was of low negative magnitude and even positive at the highest RICO altitudes. The disparity between CCN and drizzle drop concentrations precluded a causal relationship. But the high R between GN and drizzle drop concentrations at the highest altitudes (Fig. 1B) and the comparable concentrations indicated that GN were engendering drizzle. This is supported by the increasing R with altitude of the GN-drizzle drop R (right side of Fig. 1B). The conclusion of a GN-drizzle connection is also supported by the fact that CCN concentrations should inhibit drizzle. This analysis of Hudson et al. (2011) is here expanded to include correlations of CCN concentrations at lower S with cloud and drizzle drop concentrations to investigate intermediate relationships; i.e., between large nuclei (i.e., 0.1-1 micrometer; critical S 0.1-0.01%) and drizzle drop concentrations. A shortcoming of Hudson et al. (2011) was the small number of high altitude flights, which limited the significance of the R values. The very recent (July 2011) ICE-T project was a similar study in the same region (Caribbean). The greater number of high altitude cloud measurements during the summer season should provide better statistics to test the GN warm rain hypothesis.

Buffer Layer Doping Concentration Measurement Using VT-VSUB Characteristics of GaN HEMT with p-GaN Substrate Layer

NASA Astrophysics Data System (ADS)

Hu, Cheng-Yu; Nakatani, Katsutoshi; Kawai, Hiroji; Ao, Jin-Ping; Ohno, Yasuo

To improve the high voltage performance of AlGaN/GaN heterojunction field effect transistors (HFETs), we have fabricated AlGaN/GaN HFETs with p-GaN epi-layer on sapphire substrate with an ohmic contact to the p-GaN (p-sub HFET). Substrate bias dependent threshold voltage variation (VT-VSUB) was used to directly determine the doping concentration profile in the buffer layer. This VT-VSUB method was developed from Si MOSFET. For HFETs, the insulator is formed by epitaxially grown and heterogeneous semiconductor layer while for Si MOSFETs the insulator is amorphous SiO2. Except that HFETs have higher channel mobility due to the epitaxial insulator/semiconductor interface, HFETs and Si MOSFETs are basically the same in the respect of device physics. Based on these considerations, the feasibility of this VT-VSUB method for AlGaN/GaN HFETs was discussed. In the end, the buffer layer doping concentration was measured to be 2 × 1017cm-3, p-type, which is well consistent with the Mg concentration obtained from secondary ion mass spectroscopy (SIMS) measurement.

[Spatial variations of heavy metals in precipitation at Mount Taishan region].

PubMed

Wang, Yan; Liu, Xiao-Huan; Jin, Ling-Ren; Yue, Tai-Xing; Wang, De-Zhong; Wang, Wen-Xing

2007-11-01

Zn, Al, Mn, Fe, Pb, Cu, Ni, Cr, As, Cd in rain samples collected from two sites at Mount Taishan region were determined by ICP-MS, to evaluate the spatial variation characteristics of heavy metals in precipitation. Individual rain events were sampled for one whole year from Jan. to Dec. 2006. High concentrations of heavy metals were found at both sites, indicating serious heavy metal pollution. Zn was the most abundant element, accounting for 54% - 57% of the total metals concentrations. Its volume-weighted mean concentrations of precipitation at Mt-top and Mt-foot sites were 92.94 microg/L and 70.41 microg/L respectively. The following elements were Fe, Al and Mn and their concentrations were much higher than toxic heavy metals (As, Cd and Cd) except Pb (8.04 microg/L and 7.79 microg/L at two sites respectively). Comparison results between two sites suggested that heavy metal characteristics of precipitation at two sites were different, due to the influences of different ambient air conditions. Correlation analysis between two sites showed that Al, Mn, Fe, As, Cd, Pb influenced by air mass origin greatly, while Ni, Cu, Zn affected by other different factors.

Intravenous and oral suicidal e-liquid poisonings with confirmed nicotine and cotinine concentrations.

PubMed

Sommerfeld, Karina; Łukasik-Głębocka, Magdalena; Kulza, Maksymilian; Drużdż, Artur; Panieński, Paweł; Florek, Ewa; Zielińska-Psuja, Barbara

2016-05-01

The increasing availability of e-cigarettes is a potential toxicological concern. E-cigarettes appeared on the Polish market in 2006, and since 2009 they have been widely available with a new source of nicotine, the so-called e-liquid. In this paper two cases of suicidal oral and intravenous poisonings with the e-liquid are described. The clinical courses of these poisonings are presented. Nicotine and cotinine concentrations in the patient's blood were determined using high performance liquid chromatography with diode array detection. In the course of intoxication patient No. 1, classic symptoms of acute nicotine poisoning without convulsions were observed. Nicotine and cotinine concentrations measured in serum were 0.096 and 4.4mg/L, respectively. The case of patient No. 2, admission with no typical symptoms of nicotine poisoning was identified, except unconsciousness and slow respiration. Nicotine and cotinine concentrations in the serum at the time of No. 2 admissions were determined to be 0.8 and 1.3mg/L, respectively. With the increasing number of e-liquid poisonings cases, it should be aware that these products can be a readily available source of poison. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Preliminary experimental results of gas recycling subsystems except carbon dioxide concentration

NASA Technical Reports Server (NTRS)

Otsuji, K.; Sawada, T.; Satoh, S.; Kanda, S.; Matsumura, H.; Kondo, S.; Otsubo, K.

1987-01-01

Oxygen concentration and separation is an essential factor for air recycling in a controlled ecological life support system (CELSS). Furthermore, if the value of the plant assimilatory quotient is not coincident with that of the animal respiratory quotient, the recovery of oxygen from the concentrated CO2 through chemical methods will become necessary to balance the gas contents in a CELSS. Therefore, oxygen concentration and separation equipment using Salcomine and O2 recovery equipment, such as Sabatier and Bosch reactors, were experimentally developed and tested.

Analysis of new psychoactive substances in human urine by ultra-high performance supercritical fluid and liquid chromatography: Validation and comparison.

PubMed

Borovcová, Lucie; Pauk, Volodymyr; Lemr, Karel

2018-05-01

New psychoactive substances represent serious social and health problem as tens of new compounds are detected in Europe annually. They often show structural proximity or even isomerism, which complicates their analysis. Two methods based on ultra high performance supercritical fluid chromatography and ultra high performance liquid chromatography with mass spectrometric detection were validated and compared. A simple dilute-filter-and-shoot protocol utilizing propan-2-ol or methanol for supercritical fluid or liquid chromatography, respectively, was proposed to detect and quantify 15 cathinones and phenethylamines in human urine. Both methods offered fast separation (<3 min) and short total analysis time. Precision was well <15% with a few exceptions in liquid chromatography. Limits of detection in urine ranged from 0.01 to 2.3 ng/mL, except for cathinone (5 ng/mL) in supercritical fluid chromatography. Nevertheless, this technique distinguished all analytes including four pairs of isomers, while liquid chromatography was unable to resolve fluoromethcathinone regioisomers. Concerning matrix effects and recoveries, supercritical fluid chromatography produced more uniform results for different compounds and at different concentration levels. This work demonstrates the performance and reliability of supercritical fluid chromatography and corroborates its applicability as an alternative tool for analysis of new psychoactive substances in biological matrixes. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Phytoscreening and phytoextraction of heavy metals at Danish polluted sites using willow and poplar trees.

PubMed

Algreen, Mette; Trapp, Stefan; Rein, Arno

2014-01-01

The main purpose of this study was to determine typical concentrations of heavy metals (HM) in wood from willows and poplars, in order to test the feasibility of phytoscreening and phytoextraction of HM. Samples were taken from one strongly, one moderately, and one slightly polluted site and from three reference sites. Wood from both tree species had similar background concentrations at 0.5 mg kg(-1) for cadmium (Cd), 1.6 mg kg(-1) for copper (Cu), 0.3 mg kg(-1) for nickel (Ni), and 25 mg kg(-1) for zinc (Zn). Concentrations of chromium (Cr) and lead (Pb) were below or close to detection limit. Concentrations in wood from the highly polluted site were significantly elevated, compared to references, in particular for willow. The conclusion from these results is that tree coring could be used successfully to identify strongly heavy metal-polluted soil for Cd, Cu, Ni, Zn, and that willow trees were superior to poplars, except when screening for Ni. Phytoextraction of HMs was quantified from measured concentration in wood at the most polluted site. Extraction efficiencies were best for willows and Cd, but below 0.5% over 10 years, and below 1‰ in 10 years for all other HMs.

Atmospheric concentrations of polybrominated diphenyl ethers at near-source sites.

PubMed

Cahill, Thomas M; Groskova, Danka; Charles, M Judith; Sanborn, James R; Denison, Michael S; Baker, Lynton

2007-09-15

Concentrations of polybrominated diphenyl ethers (PBDEs) were determined in air samples from near suspected sources, namely an indoors computer laboratory, indoors and outdoors at an electronics recycling facility, and outdoors at an automotive shredding and metal recycling facility. The results showed that (1) PBDE concentrations in the computer laboratorywere higherwith computers on compared with the computers off, (2) indoor concentrations at an electronics recycling facility were as high as 650,000 pg/m3 for decabromodiphenyl ether (PBDE 209), and (3) PBDE 209 concentrations were up to 1900 pg/m3 at the downwind fenceline at an automotive shredding/metal recycling facility. The inhalation exposure estimates for all the sites were typically below 110 pg/kg/day with the exception of the indoor air samples adjacent to the electronics shredding equipment, which gave exposure estimates upward of 40,000 pg/kg/day. Although there were elevated inhalation exposures at the three source sites, the exposure was not expected to cause adverse health effects based on the lowest reference dose (RfD) currently in the Integrated Risk Information System (IRIS), although these RfD values are currently being re-evaluated by the U.S. Environmental Protection Agency. More research is needed on the potential health effects of PBDEs.

Occurrence and risk assessment of pharmaceutically active compounds in wastewater treatment plants. A case study: Seville city (Spain).

PubMed

Santos, J L; Aparicio, I; Alonso, E

2007-05-01

The occurrence of four anti-inflammatory drugs (diclofenac, ibuprofen, ketoprofen and naproxen), an antiepileptic drug (carbamazepine) and a nervous stimulant (caffeine) in influent and effluent samples from four wastewater treatment plants (WWTPs) in Seville was evaluated. Removal rates in the WWTPs and risk assessment of the pharmaceutically active compounds have been studied. Analytical determination was carried out by high performance liquid chromatography (HPLC) with diode array (DAD) and fluorescence (Fl) detectors after sample clean up and concentration by solid phase extraction. All pharmaceutically active compounds, except diclofenac, were detected not only in wastewater influents but also in wastewater effluents. Mean concentrations of caffeine, carbamazepine, ketoprofen and naproxen ranged between 0.28-11.44 microg l(-1) and 0.21-2.62 microg l(-1) in influent and effluent wastewater, respectively. Ibuprofen was present in the highest concentrations in the range 12.13-373.11 microg l(-1) and 0.78-48.24 microg l(-1) in influent and effluent wastewater, respectively. Removal rates of the pharmaceuticals ranged between 6 and 98%. Risk quotients, expressed as ratios between the measured environmental concentration (MEC) and the predicted no effect concentrations (PNEC) were higher than 1 for ibuprofen and naproxen in influent wastewater and for ibuprofen in effluent wastewater.

Alteration of Blood Parameters and Histoarchitecture of Liver and Kidney of Silver Barb after Chronic Exposure to Quinalphos

PubMed Central

Mohammod Mostakim, Golam; Zahangir, Md. Mahiuddin; Monir Mishu, Mahbuba; Rahman, Md. Khalilur; Islam, M. Sadiqul

2015-01-01

Quinalphos (QP) is commonly used for pest control in the agricultural fields surrounding freshwater reservoirs. This study was conducted to evaluate the chronic toxicity of this pesticide on blood parameters and some organs of silver barb, Barbonymus gonionotus. Fish were exposed to two sublethal concentrations, 0.47 ppm and 0.94 ppm, of QP for a period of 28 days. All the blood parameters (red blood cell, hematocrit, and hemoglobin) and blood glucose except for white blood cells decreased with increasing concentration of toxicant and become significantly lower (p < 0.05) at higher concentration when compared with control. The derived hematological indices of mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration were equally altered compared to control. Histoarchitectural changes of liver and kidney were observed after exposure to the QP. Hypertrophy of hepatocytes, mild to severe necrosis, ruptured central vein, and vacuolation were observed in the liver of treated groups. Highly degenerated kidney tubules and hematopoietic tissue, degeneration of renal corpuscle, vacuolization, and necrosis were evident in the kidney of treated groups. In conclusion, chronic exposure to QP at sublethal concentrations induced hematological and histological alterations in silver barb and offers a simple tool to evaluate toxicity derived alterations. PMID:26635877

Combined effects of land reclamation, channel dredging upon the bioavailable concentration of polycyclic aromatic hydrocarbons (PAHs) in Victoria Harbour sediment, Hong Kong.

PubMed

Chan, J T K; Leung, H M; Yue, P Y K; Au, C K; Wong, Y K; Cheung, K C; Li, W C; Yung, K K L

2017-01-15

The up-to-date concentration of polycyclic aromatic hydrocarbons (PAHs) in sediment materials of Victoria Harbour was investigated so as to evaluate the pollution potential associated with the reclamation projects in Hong Kong. A total of 100 sediment samples were collected at 20 locations. Except the control point in reservoir, the PAHs concentrations were detectable levels all sites (131-628.3ng/g, dw) and such values were higher than Dutch Target and Intervention Values (the New Dutch standard in 2016). The PAHs concentration indicating that construction waste and wastewater discharges were the main pollutant sources. Results of correlation in single cell gel electrophoresis assay (comet assay) studies also revealed that the PAHs concentration was highly correlated (<0.01) with DNA migration (i.e. the length of tail moment of fish cells) in 5mg/ml of PAHs. The above observation indicates that the PAHs present in the sediment may substantially effect the marine ecosystem. Although the dredged sediment can be a useful sea-filling material for land reclamation; however, the continuing leaching of PAHs and its impact on the aquatic environment need to be studied further. Copyright © 2016 Elsevier Ltd. All rights reserved.

Biomonitoring of heavy metals in feathers of eleven common bird species in urban and rural environments of Tiruchirappalli, India.

PubMed

Manjula, Menon; Mohanraj, R; Devi, M Prashanthi

2015-05-01

Heavy metals continue to remain as a major environmental concern in spite of emission control measures. In this study, we analyzed the concentrations of heavy metals (Fe, Cr, Mn, Ni, Cu, Zn, and Cd) in the feathers of 11 species of birds collected from urban and rural areas of Tiruchirappalli, Southern India. Metal concentrations followed the order: Fe > Cu > Zn > Cr > Mn > Ni > Cd. Irrespective of sample locations, heavy metals such as Fe, Cr, Ni, Zn, and Cu were detected in high concentrations, while Cd and Mn were observed in lower concentrations. In contrary to our assumption, there were no statistically significant intraspecific and urban-rural differences in the metal concentrations except for Zn. Pairwise comparisons among species irrespective of metal type showed significant interspecific differences between Acridotheres tristis and Centropus phasianinus, A. tristis and Milvus migrans, C. phasianinus and M. migrans, M. migrans and Eudynamys scolopaceus, and Psittacula krameri and E. scolopaceus. Principal component analysis carried out for urban data extracted Ni, Mn, Zn, Fe, and Cu accounting for 48% variance implying dietary intake and external contamination as important sources for metals. In the rural, association of Zn, Cd, Ni, and Cr suggests the impact of metal fabrication industries and leather tanning operations.

Elution kinetics, antimicrobial activity, and mechanical properties of 11 different antibiotic loaded acrylic bone cement.

PubMed

Gálvez-López, Ruben; Peña-Monje, Alejandro; Antelo-Lorenzo, Ramón; Guardia-Olmedo, Juan; Moliz, Juan; Hernández-Quero, José; Parra-Ruiz, Jorge

2014-01-01

Antibiotic-loaded acrylic bone cements (ALABC) spacers are routinely used in the treatment of prosthetic joint infections. The objectives of our study were to evaluate different ALABC for elution kinetics, thermal stability, and mechanical properties. A 10 or 20% mixture (w/w) beads of medium viscosity bone cement (DePuy, Inc) and vancomycin (VAN), gentamycin (GM), daptomycin (DAP), moxifloxacin (MOX), rifampicin (RIF), cefotaxime (CTX), cefepime (FEP), amoxicillin clavulanate (AmC), ampicillin (AMP), meropenem (MER), and ertapenem (ERT) were formed and placed into wells filled with phosphate-buffered saline. Antibiotic concentrations were determined using high-performance liquid chromatography. Antimicrobial activity was tested against Micrococcus luteus ATCC 9341 or Escherichia coli ATCC 25922. AmC, AMP, and FEP concentration rapidly decreased after day 2, being almost undetectable at day 4. Sustained and high elution rates were observed with VAN, GM, MOX, and RIF for the 30-day duration of the experiment. DAP, MER, ERT, and CTX elution rates constantly decreased from day 4. All antibiotics tested retained antimicrobial activity proving thermal stability. Mechanical properties of ALABC were maintained except when RIF was used. © 2013.

Peculiarities of hyperlipidaemia in tumour patients.

PubMed Central

Dilman, V. M.; Berstein, L. M.; Ostroumova, M. N.; Tsyrlina, Y. V.; Golubev, A. G.

1981-01-01

The study group included 684 cases: 258 patients with breast carcinoma, 113 males with lung cancer, 42 patients with rectal tumours, 42 patients with stomach tumours, 59 patients with fibroadenomatosis, and 170 healthy subjects of varying age (male and female). A relatively high blood triglyceride level was found in patients with breast, lung, rectal (females), and stomach (female) tumours. The blood concentration of high-density lipoprotein-cholesterol in patients with breast, lung, and stomach (female) tumours was relatively low. The elimination of tumour (breast carcinoma) did not lead to significant changes in lipid metabolism. There was no correlation between degree of lipidaemia and stage of tumour progression except in the cases of rectal cancer. Preliminary results are presented on the tentative classification of hyperlipoproteinaemia in tumour patients, using the lipid concentration threshold values advocated by Carlson et al. (1977); an increased frequency of Type IV hyperlipoproteinaemia proved to be the most characteristic feature of tumour patients. The results are discussed in terms of the concept of the importance of lipid metabolic disturbances, primarily those due to ageing, in the genesis of the syndrome of "cancerophilia" (predisposition to cancer). PMID:7248149

Peculiarities of hyperlipidaemia in tumour patients.

PubMed

Dilman, V M; Berstein, L M; Ostroumova, M N; Tsyrlina, Y V; Golubev, A G

1981-05-01

The study group included 684 cases: 258 patients with breast carcinoma, 113 males with lung cancer, 42 patients with rectal tumours, 42 patients with stomach tumours, 59 patients with fibroadenomatosis, and 170 healthy subjects of varying age (male and female). A relatively high blood triglyceride level was found in patients with breast, lung, rectal (females), and stomach (female) tumours. The blood concentration of high-density lipoprotein-cholesterol in patients with breast, lung, and stomach (female) tumours was relatively low. The elimination of tumour (breast carcinoma) did not lead to significant changes in lipid metabolism. There was no correlation between degree of lipidaemia and stage of tumour progression except in the cases of rectal cancer. Preliminary results are presented on the tentative classification of hyperlipoproteinaemia in tumour patients, using the lipid concentration threshold values advocated by Carlson et al. (1977); an increased frequency of Type IV hyperlipoproteinaemia proved to be the most characteristic feature of tumour patients. The results are discussed in terms of the concept of the importance of lipid metabolic disturbances, primarily those due to ageing, in the genesis of the syndrome of "cancerophilia" (predisposition to cancer).

Experimental study of effectiveness of four radon mitigation solutions, based on underground depressurization, tested in prototype housing built in a high radon area in Spain.

PubMed

Frutos Vázquez, Borja; Olaya Adán, Manuel; Quindós Poncela, Luis Santiago; Sainz Fernandez, Carlos; Fuente Merino, Ismael

2011-04-01

The present paper discusses the results of an empirical study of four approaches to reducing indoor radon concentrations based on depressurization techniques in underground sumps. The experiments were conducted in prototype housing built in an area of Spain where the average radon concentration at a depth of 1 m is 250 kBq m(-3). Sump effectiveness was analysed in two locations: underneath the basement, which involved cutting openings into the foundation, ground storey and roof slabs, and outside the basement walls, which entailed digging a pit alongside the building exterior. The effectiveness of both sumps was likewise tested with passive and forced ventilation methods. The systems proved to be highly efficient, lowering radon levels by 91-99%, except in the solution involving passive ventilation and the outside sump, where radon levels were reduced by 53-55%. At wind speeds of over 8 m/s, however, passive ventilation across an outside sump lowered radon levels by 95% due to a Venturi effect induced drop in pressure. Copyright © 2011 Elsevier Ltd. All rights reserved.

Occurrence and fate of anti-inflammatory drugs in wastewater treatment plants in Japan.

PubMed

Nakada, Norihide; Komori, Koya; Suzuki, Yutaka

2005-01-01

The fates of anti-inflammatory drugs (e.g., ibuprofen, naproxen, mefenamic acid and ketoprofen), which are frequently detected in the discharges of wastewater treatment plants (WWTPs) and river water in Japan, were clarified in two WWTPs. The concentrations of ibuprofen, naproxen, mefenamic acid and ketoprofen were 69-1080, 179-305, 143-1580 and 160-1060 ng/L in the influent, and N.D. (< 40 ng/L), 74-166, 72-265, 64-107 ng/L in the effluent, respectively. The concentrations of the anti-inflammatory drugs analyzed were almost equal to or lower than those reported in foreign countries. High removal efficiencies of the drugs, except ibuprofen, were observed in the WWTP that has longer hydraulic retention time than that of the other WWTP. For ibuprofen, high removal efficiencies were observed in both WWTPs (84 to 98%). Disinfection by chlorination was not effective to remove the drugs surveyed. On the other hand, the effective removal of ketoprofen by ultraviolet (UV) radiation for disinfection was demonstrated, although the disinfection by-products were not identified.

Report on Analyses of WAC Samples of Evaporator Overheads - 2004

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

OJI, LAWRENCE

2004-08-16

All water received into ETF requires characterization versus the defined Waste Acceptance Criteria. Currently much of the water received by ETF comes from the F and H Evaporator Overheads. Concentration, Storage and Transfer Engineering issued a modified list of species to be determined. In March of 2004, the Tank Farm submitted annual samples from 2F, 2H and 3H Evaporator Overhead streams for characterization to verify compliance with the Effluent Treatment Facility (ETF) Waste Acceptance Criteria (WAC) and to look for organic species. With the exception of high silicon in the 2H and slightly high tritium in 2F evaporator overheads, allmore » the overheads samples were found to be in compliance with the Effluent Treatment Facility WAC. The silicon concentration in the 2H-evaporator overhead, at 44 mg/L, was above the ETF WAC limit of 5 mg/L and tritium at 2.11E+05 dpm/mL in 2F overhead sample was above the ETF WAC limit of 1.2E+05 dpm/mL.« less

Multi-Sensory Aerosol Data and the NRL NAAPS model for Regulatory Exceptional Event Analysis

NASA Astrophysics Data System (ADS)

Husar, R. B.; Hoijarvi, K.; Westphal, D. L.; Haynes, J.; Omar, A. H.; Frank, N. H.

2013-12-01

Beyond scientific exploration and analysis, multi-sensory observations along with models are finding increasing applications for operational air quality management. EPA's Exceptional Event (EE) Rule allows the exclusion of data strongly influenced by impacts from "exceptional events," such as smoke from wildfires or dust from abnormally high winds. The EE Rule encourages the use of satellite observations and other non-standard data along with models as evidence for formal documentation of EE samples for exclusion. Thus, the implementation of the EE Rule is uniquely suited for the direct application of integrated multi-sensory observations and indirectly through the assimilation into an aerosol simulation model. Here we report the results of a project: NASA and NAAPS Products for Air Quality Decision Making. The project uses of observations from multiple satellite sensors, surface-based aerosol measurements and the NRL Aerosol Analysis and Prediction System (NAAPS) model that assimilates key satellite observations. The satellite sensor data for detecting and documenting smoke and dust events include: MODIS AOD and Images; OMI Aerosol Index, Tropospheric NO2; AIRS, CO. The surface observations include the EPA regulatory PM2.5 network; the IMPROVE/STN aerosol chemical network; AIRNOW PM2.5 mass network, and surface met. data. Within this application, crucial role is assigned to the NAAPS model for estimating the surface concentration of windblown dust and biomass smoke. The operational model assimilates quality-assured daily MODIS data and 2DVAR to adjust the model concentrations and CALIOP-based climatology to adjust the vertical profiles at 6-hour intervals. The assimilation of satellite data from multiple satellites significantly contributes to the usefulness of NAAPS for EE analysis. The NAAPS smoke and dust simulations were evaluated using the IMPROVE/STN chemical data. The multi-sensory observations along with the model simulations are integrated into a web-based Exceptional Event Decision System (EE DSS) application program, designed to support air quality analysts at the Federal and Regional EPA offices and the EE-affected States. EE DSS screening tool automatically identifies the EPA PM2.5 mass samples that are candidates for EE flagging, based mainly on the NAAPS-simulated surface concentration of dust and smoke. The AQ analysts at the States and the EPA can also use the EE DSS to gather further evidence from the examination of spatio-temporal pattern, Absorbing Aerosol Index, CO and NO2 concentration, backward and forward airmass trajectories and other signatures. Since early 2013, the DSS has been used for the identification and analysis of dozens of events. Hence, integration of multi-sensory observations and modeling with data assimilation is maturing to support real-world operational AQ management applications. The remaining challenges can be resolved by seeking ';closure' of the system components; i.e. the systematic adjustments to reconcile the satellite and surface observations, the emissions and their integration through a suitable AQ model.

Airborne Chlordane Contamination in Houses Treated for Termites at a Midwestern Air Force Base

DTIC Science & Technology

1981-02-01

to provide entry authorization. Inside air temperature and relative humidity were measured with a sling psychrometer at the time of sampling...of the houses had chlordane concentrations 21.0 Pg/m3. No correlation could be made between chlordane concentration and year of treatment except for...from 14.5 to 37.8 pg/m8, were found in houses treated in 1970. Correlation of chlordane concentration could not be made with barometric pressure

Genotoxicity evaluation of HMG CoA reductase inhibitor rosuvastatin.

PubMed

Berber, Ahmet Ali; Celik, Mustafa; Aksoy, Hüseyin

2014-07-01

The genotoxic potential of rosuvastatin as one of the statin drugs was assessed by chromosomal aberrations (CAs), micronucleus (MN) and DNA damage by comet assay in the human peripheral blood lymphocytes. Rosuvastatin was used at concentrations of 0.0625, 0.125, 0.25, 0.5 and 1 µg/mL for these in vitro assays. In all assays, a negative and positive control were also included. CA frequencies were significantly increased in all concentrations at 24 hours and significantly increased in all concentrations except 0.0625 µg/mL at 48 hours, compared to the negative control. Rosuvastatin has a decreased mitotic index (MI) at 0.5- and 1-µg/mL concentrations at 24 hours and at 0.25, 0.5 and 1 µg/mL at 48 hours. A significant increase was observed for induction of MN in all treatments, compared to the negative control. Cytokinesis-block proliferation indices were not affected by treatments with rosuvastatin. In the comet assay, significant increases in comet tail length and tail moment were observed at 0.0625-, 0.5- and 1-µg/mL concentrations. Comet intensity was significantly increased in all concentrations except 0.0625 µg/mL. According to these results, rosuvastatin is cytotoxic and clastogenic/aneugenic in human peripheral lymphocytes. Further studies should be conducted in other test systems to evaluate the full genotoxic potential of rosuvastatin.

Comparison of Serum Protein Electrophoresis Values in Wild and Captive Whooping Cranes ( Grus americana ).

PubMed

Hausmann, Jennifer C; Cray, Carolyn; Hartup, Barry K

2015-09-01

Protein electrophoresis of serum samples from endangered, wild whooping cranes ( Grus americana ) was performed to help assess the health of the only self-sustaining, migratory population in North America. Serum samples from wild adult cranes (n = 22) were taken at Aransas National Wildlife Refuge, Texas, USA during winter. Wild juvenile cranes (n = 26) were sampled at Wood Buffalo National Park, Northwest Territories, Canada, in midsummer. All captive crane samples were acquired from the International Crane Foundation, Baraboo, WI, USA. Captive adult cranes (n = 30) were sampled during annual examinations, and archived serum samples from captive juvenile cranes (n = 19) were selected to match the estimated age of wild juveniles. Wild juveniles had significantly lower concentrations of all protein fractions than wild adults, except for prealbumin and γ globulins. All protein fraction concentrations for wild juveniles were significantly lower compared with captive juveniles, except for prealbumin and γ globulins, which were higher. Wild adults had significantly greater γ globulin concentrations than captive adults. Captive juveniles had significantly lower prealbumin and albumin concentrations and albumin : globulin ratios than captive adults. The higher γ globulin concentrations in wild versus captive cranes are likely because of increased antigenic exposure and immune stimulation. Protein fraction concentrations vary significantly with age and natural history in this species. Reference intervals for serum protein electrophoresis results from captive adult whooping cranes are provided in this study.

Aerosol black carbon at an urban site-Srinagar, Northwestern Himalaya, India: Seasonality, sources, meteorology and radiative forcing

NASA Astrophysics Data System (ADS)

Bhat, Mudasir Ahmad; Romshoo, Shakil Ahmad; Beig, Gufran

2017-09-01

Black carbon (BC) mass concentration was measured first-time at a high altitude urban site-Srinagar (1600 m asl), in northwestern Himalaya, India using an Aethalometer during 2013 to study temporal variations (monthly, diurnal and seasonal), meteorological influences, source and its radiative forcing. Diurnal variations with two peaks (at 8-10 h and 20-23 h) and two dips (at 13-17 h and 0-3 h) were observed throughout the year with varying magnitude. November and April showed the highest (13.6 μg/m3) and the lowest (3.4 μg/m3) mean monthly BC concentration respectively. Seasonally, autumn displayed the highest (9.2 μg/m3) and spring the lowest (3.5 μg/m3) mean BC concentration. Annual average BC concentration was quite higher (6 μg/m3) than those reported for other high altitude stations. Wind speed, Minimum temperature and total precipitation showed a clear negative correlation with BC (r = -0.63, -0.51 and -0.55 respectively), while as, the evening relative humidity showed positive correlation (r = 0.56). During autumn, spring and winter seasons, the main source of BC at Srinagar is the biomass burning, while during summer season, equal contribution of BC is from fossil fuel and biomass burning. Back trajectory simulations revealed that, except summer, westerly air masses are the dominant winds, transporting BC from central Asia, west Asia, south Asia, Africa and some parts of Europe to Srinagar adding to its local sources. Clear-sky short wave radiative forcing of atmosphere due to BC was highest (58.2 W m-2) during autumn which leads to the increase in lower atmospheric heating rate by 1.6 K/d. The high concentration of BC observed over the high-altitude Himalayan Kashmir region has serious implications for the regional climate, hydrology and cryosphere which needs to be investigated.

Composition of gallbladder bile in healthy individuals and patients with gallstone disease from north and South India.

PubMed

Jayanthi, V; Sarika, S; Varghese, Joy; Vaithiswaran, V; Sharma, Malay; Reddy, Mettu Srinivas; Srinivasan, Vijaya; Reddy, G M M; Rela, Mohamed; Kalkura, S

2016-09-01

Gallstones (GS) in south India (SI) are predominantly pure pigment or mixed, while in North India (NI), these are either pure cholesterol or mixed. While cholesterol rich gallbladder (GB) bile predicts cholesterol GS, constituent of bile in primary pigment GS is not known. We compared the composition of GB bile from healthy liver donors and patients with GS from north and south India. Gallbladder bile from healthy liver donors from north (10) and south India (8) served as controls. Cases were patients from north (21) and south India (17) who underwent cholecystectomy for GS disease. Gallbladder bile from both cases and controls was analyzed for cholesterol, lecithin (phospholipid), and bile salts. Gallstones were classified as cholesterol, mixed, and pigment based on morphology and biochemical analysis. The median cholesterol concentration in control bile from north was significantly high compared to south (p<0.001) with no difference in lecithin and bile salts (p NS). Except for one sample each from north and south, the cholesterol solubility of controls was within the critical micellar zone. Mixed GS were most frequent in north India (61.9 %) while pigment GS dominated in south (61.9 %). The median cholesterol concentration in bile samples of cholecystectomy patients from north India was significantly high GS (p < 0.00001) with significant lowering of bile salts and lecithin (p < 0.00001). In south India, patients with mixed GS had high cholesterol content in bile compared to controls and patients with pigment GS; bile in latter had significantly higher concentration of bile salt compared to controls and mixed GS. The ternary plot confirmed the composition of GB bile from north and south India. Gallbladder bile in controls and patients with GS from north India had significantly high cholesterol concentration. In south India, patients with mixed GS had cholesterol rich bile while pigment GS had higher concentrations of bile salts.

Effect of silver nanoparticles on concentration of silver heavy element and growth indexes in cucumber ( Cucumis sativus L . negeen)

NASA Astrophysics Data System (ADS)

Shams, Gholamabbas; Ranjbar, Morteza; Amiri, Aliasghar

2013-05-01

The tremendous progress on nanoparticle research area has been made significant effects on the economy, society, and the environment. Silver nanoparticle is one of the most important particles in these categories. Silver nanoparticles can be converted to the heavy silver metal in water by oxidation. Moreover, in the high amounts of silver concentration, they will be accumulated in different parts of the plant. However, by changing the morphology of the plant, the production will be harmful for human consumptions. In this study, nano-powders with average 50 nm silver particles are mixed with deionized distilled water in a completely randomized design. Seven treatments with various concentrations of suspension silver nanoparticles were prepared and repeated in four different parts of the plant in a regular program of spraying. Samples were analyzed to study the growth indexes and concentration of silver in different parts of the plant. It was observed that with increasing concentration of silver nanoparticles on cucumber, the growth indexes (except pH fruit), and the concentration of silver heavy metal are increased significantly. The incremental concentration had the linear relationship with correlation coefficient 0.95 and an average of 0.617 PPM by increasing of each unit in one thousand concentration of nanosilver. Although, by increasing concentration of silver nanoparticles as spraying form, the plant morphological characteristics were improved, the concentration of silver heavy metal in various plant organs was increased. These results open a new pathway to consider the effect of nanoparticles on plant's productions for human consumptions.

Ammonium in thermal waters of Yellowstone National Park: processes affecting speciation and isotope fractionation

USGS Publications Warehouse

Holloway, J.M.; Nordstrom, D. Kirk; Böhlke, J.K.; McCleskey, R. Blaine; Ball, J.W.

2011-01-01

Dissolved inorganic nitrogen, largely in reduced form (NH4(T)≈NH4(aq)++NH3(aq)o), has been documented in thermal waters throughout Yellowstone National Park, with concentrations ranging from a few micromolar along the Firehole River to millimolar concentrations at Washburn Hot Springs. Indirect evidence from rock nitrogen analyses and previous work on organic compounds associated with Washburn Hot Springs and the Mirror Plateau indicate multiple sources for thermal water NH4(T), including Mesozoic marine sedimentary rocks, Eocene lacustrine deposits, and glacial deposits. A positive correlation between NH4(T) concentration and δ18O of thermal water indicates that boiling is an important mechanism for increasing concentrations of NH4(T) and other solutes in some areas. The isotopic composition of dissolved NH4(T) is highly variable (δ15N = −6‰ to +30‰) and is positively correlated with pH values. In comparison to likely δ15N values of nitrogen source materials (+1‰ to +7‰), high δ15N values in hot springs with pH >5 are attributed to isotope fractionation associated with NH3(aq)o loss by volatilization. NH4(T) in springs with low pH typically is relatively unfractionated, except for some acid springs with negative δ15N values that are attributed to NH3(g)o condensation. NH4(T) concentration and isotopic variations were evident spatially (between springs) and temporally (in individual springs). These variations are likely to be reflected in biomass and sediments associated with the hot springs and outflows. Elevated NH4(T) concentrations can persist for 10s to 1000s of meters in surface waters draining hot spring areas before being completely assimilated or oxidized.

Health risk assessment from contaminated foodstuffs: a field study in chromite mining-affected areas northern Pakistan.

PubMed

Nawab, Javed; Li, Gang; Khan, Sardar; Sher, Hassan; Aamir, Muhammad; Shamshad, Isha; Khan, Anwarzeb; Khan, Muhammad Amjad

2016-06-01

This study aimed to investigate the potential health risk associated with toxic metals in contaminated foodstuffs (fruits, vegetables, and cereals) collected from various agriculture fields present in chromite mining-affected areas of mafic and ultramafic terrains (northern Pakistan). The concentrations of Cr, Ni, Zn, Cd, and Pb were quantified in both soil and food samples. The soil samples were highly contaminated with Cr (320 mg/kg), Ni (108 mg/kg), and Cd (2.55 mg/kg), which exceeded their respective safe limits set by FAO/WHO. Heavy metal concentrations in soil were found in the order of Cr>Ni>Pb>Zn>Cd and showed significantly (p < 0.001) higher concentrations as compared to reference soil. The integrated pollution load index (PLI) value was observed greater than three indicating high level of contamination in the study area. The concentrations of Cr (1.80-6.99 mg/kg) and Cd (0.21-0.90 mg/kg) in foodstuffs exceeded their safe limits, while Zn, Pb, and Ni concentrations were observed within their safe limits. In all foodstuffs, the selected heavy metal concentrations were accumulated significantly (p < 0.001) higher as compared to the reference, while some heavy metals were observed higher but not significant like Zn in pear, persimmon, white mulberry, and date-plum; Cd in pear, fig and white mulberry; and Pb in walnut, fig, and pumpkin. The health risk assessment revealed no potential risk for both adults and children for the majority of heavy metals, except Cd, which showed health risk index (HRI) >1 for children and can pose potential health threats for local inhabitants. Graphical Abstract Heavy metals released from chromite mining lead to soil and foodstuff contamination and human health risk.

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

Broxton, D.E.

A total of 338 water and 1877 sediment samples were collected over a 20,700-km/sup 2/ area from 2125 locations at a nominal density of one sample per 10 km/sup 2/. Water samples were collected from wells, streams, springs, and artificial ponds. Sediment samples were collected from streams, springs, natural ponds, and artificial ponds. Arbitrary anomaly thresholds of two standard deviations above the mean were chosen for both water and sediment sample populations. The U concentrations in waters collected in the Tularosa quadrangle range from below the detection limit of 0.2 parts per billion (ppB) to 57.8 ppB. Most clusters ofmore » water samples containing anomalously high uranium concentrations were collected from locations in uplifts underlain either by volcanic rocks of the mid-Tertiary Datil group or by sedimentary rocks of late Paleozoic and Mesozoic age. Other groups of anomalous waters are from wells that tap Cenozoic aquifers in the intermontane basins. In those areas where the water-sample location coverage is adequate, the known U occurrences are generally associated with high or anomalous U concentrations in water samples. With the exception of one sample with a U concentration of 67.7 ppM, sediments collected in this study have U concentrations that range between 0.2 and 15.2 ppM. Most sediments with U concentrations above the arbitrary anomaly threshold value are from locations which occur in or parallel outcrops of Precambrian crystalline rock exposed in the San Andres and Oscura Mountains. Other anomalous sediments occur as more discreet groups in areas underlain by mid-Tertiary volcanic rocks of the Datil group. Several anomalous samples from the Mogollon-Datil volcanic field were collected along ring fracture systems that surround large volcanic cauldrons.« less

Hormetic effects of noncoplanar PCB exposed to human lung fibroblast cells (HELF) and possible role of oxidative stress.

PubMed

Hashmi, Muhammad Zaffar; Khan, Kiran Yasmin; Hu, Jinxing; Naveedullah; Su, Xiaomei; Abbas, Ghulam; Yu, Chunna; Shen, Chaofeng

2015-12-01

Hormesis, a biphasic dose-response phenomenon, which is characterized by stimulation of an end point at a low-dose and inhibition at a high-dose. In the present study we used human lungs fibroblast (HELF) cells as a test model to evaluate the role of oxidative stress (OS) in hormetic effects of non coplanar PCB 101. Results from 3-(4,5-dime-thylthiazol-2-yl)-2,5-diphenyltetrazo-lium bromide (MTT) assay indicated that PCB101 at lower concentrations (10(-5) to 10(-1) μg mL(-1) ) stimulated HELF cell proliferation and inhibited at high concentrations (1, 5, 10, and 20 μg mL(-1) ) in a dose- and time-dependent manner. Reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) (except 48 h) showed a significant increase at higher concentrations of PCB 101 than those at the lower concentrations with the passage of time. Antioxidant enzymes such as glutathione peroxidase (GSH-Px) exhibited decreasing trends in dose and time dependent manner. Lipid peroxidation assay resulted in a significant increase (P < 0.05) of MDA level in PCB 101-treated HELF cells compared with controls, suggesting that OS plays a key role in PCB 101-induced toxicity. Comet assay indicated a significant increase in genotoxicity at higher concentrations of PCB 101 exposure compared to lower concentrations. Overall, we found that HELF cell proliferation was higher at low ROS level and vice versa, which revealed activation of cell signaling-mediated hormetic mechanisms. The results suggested that PCB 101 has hormetic effects to HELF cells and these were associated with oxidative stress. © 2014 Wiley Periodicals, Inc.

Heavy metals distribution in soils surrounding an abandoned mine in NW Madrid (Spain) and their transference to wild flora.

PubMed

Moreno-Jiménez, Eduardo; Peñalosa, Jesús M; Manzano, Rebeca; Carpena-Ruiz, Ramón O; Gamarra, Roberto; Esteban, Elvira

2009-03-15

The present work concerns the distribution and mobility of heavy metals (Fe, Mn, Cu, Zn and Cd) in the surrounding soils of a mine site and their transfer to wild flora. Thus, soils and plants were sampled from a mining valley in NW Madrid (Spain), and total and extractable heavy metals were analysed. Soils affected by mining activities presented total Cd, Cu and Zn concentrations above toxic thresholds. The percentage of extractable element was highest for Cd and lowest for Cu. A highly significant correlation was observed between the total and extractable concentrations of metals in soils, indicating that, among the factors studied, total metals concentration is the most relevant for heavy metals extractability in these soils. (NH(4))(2)SO(4)-extractable metal concentrations in soils are correlated better with metal concentrations in several plant species than total metals in soils, and thus can be used as a suitable and robust method for the estimation of the phytoavailable fraction present in soils. Twenty-five vascular plant species (3 ferns and 22 flowering plants) were analysed, in order to identify exceptional characteristics that would be interesting for soil phytoremediation and/or reclamation. High Cd and Zn concentrations have been found in the aerial parts of Hypericum perforatum (Cd), Salix atrocinerea (Cd, Zn) and Digitalis thapsi (Cd, Zn). The present paper is, to the best of our knowledge, the first report of the metal accumulation ability of the two latter plant species. The phytoremediation ability of S. atrocinerea for Cd and Zn was estimated, obtaining intervals of time that could be considered suitable for the phytoextraction of polluted soils.

Questa baseline and pre-mining ground-water quality investigation. 20. Water chemistry of the Red River and selected seeps, tributaries, and precipitation, Taos County, New Mexico, 2000-2004

USGS Publications Warehouse

Verplanck, P.L.; McCleskey, R. Blaine; Nordstrom, D. Kirk

2006-01-01

As part of a multi-year project to infer the pre-mining ground-water quality at Molycorp's Questa mine site, surface-water samples of the Red River, some of its tributaries, seeps, and snow samples were collected for analysis of inorganic solutes and of water and sulfate stable isotopes in selected samples. The primary aim of this study was to document diel, storm event, and seasonal variations in water chemistry for the Red River and similar variations in water chemistry for Straight Creek, a natural analog site similar in topography, hydrology, and geology to the mine site for inferring pre-mining water-quality conditions. Red River water samples collected between 2000 and 2004 show that the largest variations in water chemistry occur during late summer rainstorms, often monsoonal in nature. Within hours, discharge of the Red River increased from 8 to 102 cubic feet per second and pH decreased from 7.80 to 4.83. The highest concentrations of metals (iron, aluminum, zinc, manganese) and sulfate also occur during such events. Low-pH and high-solute concentrations during rainstorm runoff are derived primarily from alteration 'scar' areas of naturally high mineralization combined with steep topography that exposes continually altered rock because erosion is too rapid for vegetative growth. The year 2002 was one of the driest on record, and Red River discharge reflected the low seasonal snow pack. No snowmelt peak appeared in the hydrograph record, and a late summer storm produced the highest flow for the year. Snowmelt was closer to normal during 2003 and demonstrated the dilution effect of snowmelt on water chemistry. Two diel sampling events were conducted for the Red River, one during low flow and the other during high flow, at two locations, at the Red River gaging station and just upstream from Molycorp's mill site. No discernible diel trends were observed except for dissolved zinc and manganese at the upstream site during low flow. Straight Creek drainage water was sampled periodically from 2001 to 2004 at the down stream end of surface drainage near the point at which it disappeared into the debris fan. This water has a minimal range in pH (2.7 to 3.2) but a substantial concentration range in many solutes; for example, sulfate concentrations varied from 525 to 2,660 mg/L. Many elements covary with sulfate suggesting that dilution is the primary control of the range in solute concentrations. A transect of water samples higher in the scar area were collected in October of 2003. They had a lower range in pH (2.44 to 3.05) and higher solute concentrations than those collected periodically from lower in the catchment. Water isotopes for the upper transect samples indicated slight evaporation, and in part, may account for the higher solute concentrations. Drainage waters also were collected from Hottentot, Junebug, Hansen, Little Hansen, and Goat Hill Gulch drainages. Most constituents from other scar drainage waters showed ranges of concentration similar to those of the Straight Creek waters. An exception was water collected from Goat Hill Gulch, which has some of the highest concentrations of any surface-water sample collected but also contained waste-rock leachates.

Compositionally Controlled Volatile Content of Nominally Volatile-Free Minerals in the Continental Upper Mantle of Southern Gondwana (Patagonia & W. Antarctica)

NASA Astrophysics Data System (ADS)

Rooks, E. E.; Gibson, S. A.; Leat, P. T.; Petrone, C. M.

2015-12-01

H2O and F contents affect many physical and chemical properties of the upper mantle, including melting temperature and viscosity. These elements are hosted by hydrous and F-rich phases, and by modally abundant, nominally-anhydrous/halogen-free mantle minerals, which can potentially accommodate the entire volatile budget of the upper mantle. We present high-precision SIMS analyses of H2O, and F in mantle xenoliths hosted by recently-erupted (5-10 Ka) alkali basalts from south Patagonia (Pali Aike) and older (c. 25 Ma) alkali basalts from localities along the Antarctic Peninsula. Samples are well characterised peridotites and pyroxenites, from a range of depths in the off-craton lithospheric mantle. Minerals are relatively dry: H2O contents of olivine span 0-49 ppm, orthopyroxene 150-235 ppm and clinopyroxene 100-395 ppm, with highest concentrations found in spinel-garnet lherzolites from Pali Aike. These H2O concentrations fall within the global measured range for off-craton mantle minerals. H2O and F are correlated, and the relative compatibility of F in mantle phases is clinopyroxene>orthopyroxene>olivine. However, elevated F concentrations of 100-210 ppm are found in pyroxenites from two Antarctic localities. This elevated F content is not correlated with high H2O, suggesting that these rocks interacted with a F-rich melt. In clinopyroxenes, F concentration is correlated with Ti, and the ratio of M1Ti to M1Al + M1Cr, suggesting a charge balanced substitution. Consistency between samples (excepting high-F pyroxenites) suggests a constant F-budget, and that concentrations in clinopyroxenes are controlled by mineral chemistry. In orthopyroxene, F correlates with CaO, but no other major or minor elements. Large variability of H2O concentrations within samples is attributed to diffusive loss during ascent. Cl is negligible in all samples, indicating little or no influence of slab fluids from this long-lived subduction zone.

Annual and diurnal variations of gaseous and particulate pollutants in 31 provincial capital cities based on in situ air quality monitoring data from China National Environmental Monitoring Center.

PubMed

Zhao, Suping; Yu, Ye; Yin, Daiying; He, Jianjun; Liu, Na; Qu, Jianjun; Xiao, Jianhua

2016-01-01

Long-term air quality data with high temporal and spatial resolutions are needed to understand some important processes affecting the air quality and corresponding environmental and health effects. The annual and diurnal variations of each criteria pollutant including PM2.5 and PM10 (particulate matter with aerodynamic diameter less than 2.5 μm and 10 μm, respectively), CO (carbon monoxide), NO2 (nitrogen dioxide), SO2 (sulfur dioxide) and O3 (ozone) in 31 provincial capital cities between April 2014 and March 2015 were investigated by cluster analysis to evaluate current air pollution situations in China, and the cities were classified as severely, moderately, and slightly polluted cities according to the variations. The concentrations of air pollutants in winter months were significantly higher than those in other months with the exception of O3, and the cities with the highest CO and SO2 concentrations were located in northern China. The annual variation of PM2.5 concentrations in northern cities was bimodal with comparable peaks in October 2014 and January 2015, while that in southern China was unobvious with slightly high PM2.5 concentrations in winter months. The concentrations of particulate matter and trace gases from primary emissions (SO2 and CO) and NO2 were low in the afternoon (~16:00), while diurnal variation of O3 concentrations was opposite to that of other pollutants with the highest values in the afternoon. The most polluted cities were mainly located in North China Plain, while slightly polluted cities mostly focus on southern China and the cities with high altitude such as Lasa. This study provides a basis for the formulation of future urban air pollution control measures in China. Copyright © 2015 Elsevier Ltd. All rights reserved.

Differences in spatiotemporal variations of atmospheric PAH levels between North America and Europe: data from two air monitoring projects.

PubMed

Liu, Liang-Ying; Kukučka, Petr; Venier, Marta; Salamova, Amina; Klánová, Jana; Hites, Ronald A

2014-03-01

Atmospheric concentrations of high molecular weight polycyclic aromatic hydrocarbons (PAHs) were measured at five sites for almost two decades near the North American Great Lakes, as part of the Integrated Atmospheric Deposition Network (IADN), and at three remote sites around Europe, as part of the European Monitoring and Evaluation Programme (EMEP). The primary objectives were to reveal the spatial distributions, long-term temporal trends, and seasonal variations of atmospheric PAH concentrations and to investigate potential differences between these two regions. Atmospheric PAH concentrations at the urban sites in Chicago and Cleveland near Great Lakes were about 20 times (depending on PAH congener and sampling site) greater than those at the rural sites except for Košetice in the Czech Republic. Atmospheric PAH concentrations at Košetice, also a rural site, were about one-third of those at Chicago and Cleveland, but 10 times higher than those at other rural sites (Sturgeon Point, Sleeping Bear Dunes, Eagle Harbor, Aspvreten, and Spitsbergen). Significant long-term decreasing trends of all these PAH atmospheric concentrations were observed at Chicago and Cleveland. For the other sites, either less significant or no long-term decreasing trends were observed. Clear seasonality was observed at Sturgeon Point, Sleeping Bear Dunes, Košetice, and Spitsbergen, with the highest PAH concentrations observed in mid-January. Copyright © 2013 Elsevier Ltd. All rights reserved.

Concentrations and geographical variations of selected toxic elements in meat from semi-domesticated reindeer (Rangifer tarandus tarandus L.) in mid- and northern Norway: evaluation of risk assessment.

PubMed

Hassan, Ammar Ali; Brustad, Magritt; Sandanger, Torkjel M

2012-05-01

Meat samples (n = 100) from semi-domesticated reindeer (Rangifer tarandus tarandus L.) were randomly collected from 10 grazing districts distributed over four Norwegian counties in 2008 and 2009. The main aim was to study concentrations and geographical variations in selected toxic elements; cadmium (Cd), lead (Pb), arsenic (As), copper (Cu), nickel (Ni) and vanadium (V) in order to assess the risk associated with reindeer meat consumption. Sample solutions were analysed using an inductively coupled plasma high resolution mass spectrometer (ICP-HRMS), whereas analysis of variance (ANOVA) was used for statistical analyses. Geographical variations in element concentrations were revealed, with As and Cd demonstrating the largest geographical differences. No clear geographical gradient was observed except for the east-west downward gradient for As. The As concentrations were highest in the vicinity of the Russian border, and only Cd was shown to increase with age (p < 0.05). Sex had no significant effect on the concentration of the studied elements. The concentrations of all the studied elements in reindeer meat were generally low and considerably below the maximum levels (ML) available for toxic elements set by the European Commission (EC). Thus, reindeer meat is not likely to be a significant contributor to the human body burden of toxic elements.

Data Validation Package August 2015 Groundwater Sampling at the Grand Junction, Colorado, Disposal Site October 2015

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

Frazier, William; Baur, Gary

Sampling Period: August 4, 2015. The 1998 Interim Long-Term Surveillance Plan for the Cheney Disposal Site Near Grand Junction, Colorado, requires annual monitoring to assess the performance of the disposal cell. Monitoring wells 0731, 0732, and 0733 were sampled as specified in the plan. Sampling and analyses were conducted in accordance with Sampling and Analysis Plan for the U.S. Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated). The water level was measured at each sampled well. The water level in well 0733, located in the disposal cell, is lower than water levels in adjacent wells 0731 andmore » 0732, indicating a hydraulic gradient toward the disposal cell. Results from this sampling event were generally consistent with results from the past as shown in the attached concentration-versus-time graphs. There have been no large changes in contaminant concentration observed over the last several years with the following exception. The uranium concentration in well 0733 has been trending upward since 2003. High uranium concentrations are expected in this well because it is located in the disposal cell. The selenium concentrations observed in wells 0731 and 0732 are elevated when compared to the disposal cell 0733. Wells 0731 and 0732 are completed at the alluvium/Mancos contact; here, elevated selenium concentrations are expected due to contributions from the Mancos shale.« less

Characterization of black carbon in the ambient air of Agra, India: Seasonal variation and meteorological influence

NASA Astrophysics Data System (ADS)

Gupta, Pratima; Singh, Shalendra Pratap; Jangid, Ashok; Kumar, Ranjit

2017-09-01

This study characterizes the black carbon in Agra, India home to the Taj Mahal—and situated in the Indo-Gangetic basin. The mean black carbon concentration is 9.5 μg m-3 and, owing to excessive biomass/fossil fuel combustion and automobile emissions, the concentration varies considerably. Seasonally, the black carbon mass concentration is highest in winter, probably due to the increased fossil fuel consumption for heating and cooking, apart from a low boundary layer. The nocturnal peak rises prominently in winter, when the use of domestic heating is excessive. Meanwhile, the concentration is lowest during the monsoon season because of the turbulent atmospheric conditions and the process of washout by precipitation. The ratio of black carbon to brown carbon is less than unity during the entire study period, except in winter (December). This may be because that biomass combustion and diesel exhaust are major black carbon contributors in this region, while a higher ratio in winter may be due to the increased consumption of fossil fuel and wood for heating purposes. ANOVA reveals significant monthly variation in the concentration of black carbon; plus, it is negatively correlated with wind speed and temperature. A high black carbon mass concentration is observed at moderate (1-2 m s-1) wind speed, as compared to calm or turbulent atmospheric conditions.

Biomonitoring of Trace Metals in the Keban Dam Reservoir (Turkey) Using Mussels (Unio elongatulus eucirrus) and Crayfish (Astacus leptodactylus).

PubMed

Varol, Memet; Sünbül, Muhammet Raşit

2018-01-03

Freshwater mussels and crayfish are commonly used as biomonitors of trace metals. In the present study, the concentrations of ten metals were determined in mussels (Unio elongatulus eucirrus) and crayfish (Astacus leptodactylus) collected from the Keban Dam Reservoir in Turkey. The significant spatial differences in concentrations of studied metals except As in mussels were not found. However, Co, Cr, Cu, and Zn concentrations in mussels and As, Co, Cu, Fe, Pb, and Zn concentrations in crayfish showed significant seasonal differences. As, Cd, and Mn levels in mussels were about nine times higher than those in crayfish. The concentrations of Cd, Cr, Cu, Pb, Zn, and inorganic As in crayfish and mussels were lower than maximum permissible levels. When compared with other biomonitoring studies using mussels and crayfish, high concentrations of As, Cd, Co, Cr, and Ni in mussels and Cr and Ni in crayfish were observed due to lithogenic sources and anthropogenic activities in the basin. Bioconcentration factor values of Fe, Mn, Cd, and Zn in mussels and Zn, Cu, Fe, and Co in crayfish were > 1000, which indicates that both U. e. eucirrus and A. leptodactylus have potential to bioaccumulate these metals. Therefore, attention should be paid to mussels and crayfish from ecological and human health perspective, because they are potential vectors of metals to higher trophic levels.

Concentrations and Geographical Variations of Selected Toxic Elements in Meat from Semi-Domesticated Reindeer (Rangifer tarandus tarandus L.) in Mid- and Northern Norway: Evaluation of Risk Assessment

PubMed Central

Hassan, Ammar Ali; Brustad, Magritt; Sandanger, Torkjel M.

2012-01-01

Meat samples (n = 100) from semi-domesticated reindeer (Rangifer tarandus tarandus L.) were randomly collected from 10 grazing districts distributed over four Norwegian counties in 2008 and 2009. The main aim was to study concentrations and geographical variations in selected toxic elements; cadmium (Cd), lead (Pb), arsenic (As), copper (Cu), nickel (Ni) and vanadium (V) in order to assess the risk associated with reindeer meat consumption. Sample solutions were analysed using an inductively coupled plasma high resolution mass spectrometer (ICP-HRMS), whereas analysis of variance (ANOVA) was used for statistical analyses. Geographical variations in element concentrations were revealed, with As and Cd demonstrating the largest geographical differences. No clear geographical gradient was observed except for the east-west downward gradient for As. The As concentrations were highest in the vicinity of the Russian border, and only Cd was shown to increase with age (p < 0.05). Sex had no significant effect on the concentration of the studied elements. The concentrations of all the studied elements in reindeer meat were generally low and considerably below the maximum levels (ML) available for toxic elements set by the European Commission (EC). Thus, reindeer meat is not likely to be a significant contributor to the human body burden of toxic elements. PMID:22754467

A Modeling Investigation of Human Exposure to Select Traffic-Related Air Pollutants in the Tampa Area: Spatiotemporal Distributions of Concentrations, Social Distributions of Exposures, and Impacts of Urban Design on Both

NASA Astrophysics Data System (ADS)

Yu, Haofei

Increasing vehicle dependence in the United States has resulted in substantial emissions of traffic-related air pollutants that contribute to the deterioration of urban air quality. Exposure to urban air pollutants trigger a number of public health concerns, including the potential of inequality of exposures and health effects among population subgroups. To better understand the impact of traffic-related pollutants on air quality, exposure, and exposure inequality, modeling methods that can appropriately characterize the spatiotemporally resolved concentration distributions of traffic-related pollutants need to be improved. These modeling methods can then be used to investigate the impacts of urban design and transportation management choices on air quality, pollution exposures, and related inequality. This work will address these needs with three objectives: 1) to improve modeling methods for investigating interactions between city and transportation design choices and air pollution exposures, 2) to characterize current exposures and the social distribution of exposures to traffic-related air pollutants for the case study area of Hillsborough County, Florida, and 3) to determine expected impacts of urban design and transportation management choices on air quality, air pollution exposures, and exposure inequality. To achieve these objectives, the impacts of a small-scale transportation management project, specifically the '95 Express' high occupancy toll lane project, on pollutant emissions and nearby air quality was investigated. Next, a modeling method capable of characterizing spatiotemporally resolved pollutant emissions, concentrations, and exposures was developed and applied to estimate the impact of traffic-related pollutants on exposure and exposure inequalities among several population subgroups in Hillsborough County, Florida. Finally, using these results as baseline, the impacts of sprawl and compact urban forms, as well as vehicle fleet electrification, on air quality, pollution exposure, and exposure inequality were explored. Major findings include slightly higher pollutant emissions, with the exception of hydrocarbons, due to the managed lane project. Results also show that ambient concentration contributions from on-road mobile sources are disproportionate to their emissions. Additionally, processes not captured by the CALPUFF model, such as atmospheric formation, contribute substantially to ambient concentration levels of the secondary pollutants such as acetaldehyde and formaldehyde. Exposure inequalities for NOx, 1,3-butadiene, and benzene air pollution were found for black, Hispanic, and low income (annual household income less than $20,000) subgroups at both short-term and long-term temporal scales, which is consistent with previous findings. Exposure disparities among the subgroups are complex, and sometimes reversed for acetaldehyde and formaldehyde, due primarily to their distinct concentration distributions. Compact urban form was found to result in lower average NOx and benzene concentrations, but higher exposure for all pollutants except for NOx when compared to sprawl urban form. Evidence suggests that exposure inequalities differ between sprawl and compact urban forms, and also differ by pollutants, but are generally consistent at both short and long-term temporal scales. In addition, vehicle fleet electrification was found to result in generally lower average pollutant concentrations and exposures, except for NOx. However, the elimination of on-road mobile source emissions does not substantially reduce exposure inequality. Results and findings from this work can be applied to assist transportation infrastructure and urban planning. In addition, method developed here can be applied elsewhere for better characterization of air pollution concentrations, exposure and related inequalities.

Does vaccination ensure protection? Assessing diphtheria and tetanus antibody levels in a population of healthy children

PubMed Central

Gowin, Ewelina; Wysocki, Jacek; Kałużna, Ewelina; Świątek-Kościelna, Bogna; Wysocka-Leszczyńska, Joanna; Michalak, Michał; Januszkiewicz-Lewandowska, Danuta

2016-01-01

Abstract Vaccination effectiveness is proven when the disease does not develop after a patient is exposed to the pathogen. In the case of rare diseases, vaccination effectiveness is assessed by monitoring specific antibody levels in the population. Such recurrent analyses allow the evaluation of vaccination programs. The primary schedule of diphtheria and tetanus vaccinations is similar in various countries, with differences mainly in the number and timing of booster doses. The aim of the study was to assess diphtheria and tetanus antibody concentrations in a population of healthy children. Diphtheria and tetanus antibody levels were analyzed in a group of 324 children aged 18 to 180 months. All children were vaccinated in accordance with the Polish vaccination schedule. Specific antibody concentrations greater than 0.1 IU/mL were considered protective against tetanus or diphtheria. Levels above 1.0 were considered to ensure long-term protection. Protective levels of diphtheria antibodies were found in 229 patients (70.46%), and of tetanus in 306 patients (94.15%). Statistically significant differences were found in tetanus antibody levels in different age groups. Mean concentrations and the percentage of children with high tetanus antibody titers increased with age. No similar correlation was found for diphtheria antibodies. High diphtheria antibody levels co-occurred in 72% of the children with high tetanus antibody levels; 95% of the children with low tetanus antibody levels had low levels of diphtheria antibodies. The percentage of children with protective diphtheria antibody levels is lower than that in the case of tetanus antibodies, both in Poland and abroad, but the high proportion of children without diphtheria protection in Poland is an exception. This is all the more puzzling when taking into account that Polish children are administered a total of 5 doses containing a high concentration of diphtheria toxoid, at intervals shorter than 5 years. The decrease in antibody titers occurring over time is a significant factor in vaccination program planning. Tetanus antibody concentrations were found to be high, but responses to the diphtheria and tetanus components were divergent. The percentage of children protected against diphtheria was significantly lower than protected against tetanus. PMID:27930568

Does vaccination ensure protection? Assessing diphtheria and tetanus antibody levels in a population of healthy children: A cross-sectional study.

PubMed

Gowin, Ewelina; Wysocki, Jacek; Kałużna, Ewelina; Świątek-Kościelna, Bogna; Wysocka-Leszczyńska, Joanna; Michalak, Michał; Januszkiewicz-Lewandowska, Danuta

2016-12-01

Vaccination effectiveness is proven when the disease does not develop after a patient is exposed to the pathogen. In the case of rare diseases, vaccination effectiveness is assessed by monitoring specific antibody levels in the population. Such recurrent analyses allow the evaluation of vaccination programs. The primary schedule of diphtheria and tetanus vaccinations is similar in various countries, with differences mainly in the number and timing of booster doses. The aim of the study was to assess diphtheria and tetanus antibody concentrations in a population of healthy children.Diphtheria and tetanus antibody levels were analyzed in a group of 324 children aged 18 to 180 months. All children were vaccinated in accordance with the Polish vaccination schedule.Specific antibody concentrations greater than 0.1 IU/mL were considered protective against tetanus or diphtheria. Levels above 1.0 were considered to ensure long-term protection.Protective levels of diphtheria antibodies were found in 229 patients (70.46%), and of tetanus in 306 patients (94.15%). Statistically significant differences were found in tetanus antibody levels in different age groups. Mean concentrations and the percentage of children with high tetanus antibody titers increased with age. No similar correlation was found for diphtheria antibodies. High diphtheria antibody levels co-occurred in 72% of the children with high tetanus antibody levels; 95% of the children with low tetanus antibody levels had low levels of diphtheria antibodies.The percentage of children with protective diphtheria antibody levels is lower than that in the case of tetanus antibodies, both in Poland and abroad, but the high proportion of children without diphtheria protection in Poland is an exception. This is all the more puzzling when taking into account that Polish children are administered a total of 5 doses containing a high concentration of diphtheria toxoid, at intervals shorter than 5 years. The decrease in antibody titers occurring over time is a significant factor in vaccination program planning.Tetanus antibody concentrations were found to be high, but responses to the diphtheria and tetanus components were divergent. The percentage of children protected against diphtheria was significantly lower than protected against tetanus.

Development of mercuric iodide uncooled x ray detectors and spectrometers

NASA Technical Reports Server (NTRS)

Iwanczyk, Jan S.

1990-01-01

The results obtained in the development of miniature, lowpower, light weight mercuric iodide, HgI2, x ray spectrometers for future space missions are summarized. It was demonstrated that HgI2 detectors can be employed in a high resolution x ray spectrometer, operating in a scanning electron microscope. Also, the development of HgI2 x ray detectors to augment alpha backscattering spectrometers is discussed. These combination instruments allow for the identification of all chemical elements, with the possible exception of hydrogen, and their respective concentrations. Additionally, further investigations of questions regarding radiation damage effects in the HgI2 x ray detectors are reported.

A continuous-flow denuder for the measurement of ambient concentrations and surface-exchange fluxes of ammonia

NASA Astrophysics Data System (ADS)

Wyers, G. P.; Otjes, R. P.; Slanina, J.

A new diffusion denuder is described for the continuous measurement of atmospheric ammonia. Ammonia is collected in an absorption solution in a rotating denuder, separated from interfering compounds by diffusion through a semi-permeable membrane and detected by conductometry. The method is free from interferences by other atmospheric gases, with the exception of volatile amines. The detection limit is 6 ng m -3 for a 30-min integration time. This compact instrument is fully automated and suited for routine deployment in field studies. The precision is sufficiently high for micrometeorological studies of air-surface exchange of ammonia.

The distribution of sulfur dioxide and other infrared absorbers on the surface of Io

USGS Publications Warehouse

Carlson, R.W.; Smythe, W.D.; Lopes-Gautier, R. M. C.; Davies, A.G.; Kamp, L.W.; Mosher, J.A.; Soderblom, L.A.; Leader, F.E.; Mehlman, R.; Clark, R.N.; Fanale, F.P.

1997-01-01

The Galileo Near Infrared Mapping Spectrometer was used to investigate the distribution and properties of sulfur dioxide over the surface of Io, and qualitative results for the anti-Jove hemisphere are presented here. SO2, existing as a frost, is found almost everywhere, but with spatially variable concentration. The exceptions are volcanic hot spots, where high surface temperatures promote rapid vaporization and can produce SO2-free areas. The pervasive frost, if fully covering the cold surface, has characteristic grain sizes of 30 to 100 Urn, or greater. Regions of greater sulfur dioxide concentrations are found. The equatorial Colchis Regio area exhibits extensive snowfields with large particles (250 to 500 ??m diameter, or greater) beneath smaller particles. A weak feature at 3.15 ??m is observed and is perhaps due to hydroxides, hydrates, or water. A broad absorption in the 1 ??m region, which could be caused by iron-containing minerals, shows a concentration in Io'S southern polar region, with an absence in the Pele plume deposition ring. Copyright 1997 by the American Geophysical Union.

A marine secondary producer respires and feeds more in a high CO2 ocean.

PubMed

Li, Wei; Gao, Kunshan

2012-04-01

Climate change mediates marine chemical and physical environments and therefore influences marine organisms. While increasing atmospheric CO(2) level and associated ocean acidification has been predicted to stimulate marine primary productivity and may affect community structure, the processes that impact food chain and biological CO(2) pump are less documented. We hypothesized that copepods, as the secondary marine producer, may respond to future changes in seawater carbonate chemistry associated with ocean acidification due to increasing atmospheric CO(2) concentration. Here, we show that the copepod, Centropages tenuiremis, was able to perceive the chemical changes in seawater induced under elevated CO(2) concentration (>1700 μatm, pH<7.60) with avoidance strategy. The copepod's respiration increased at the elevated CO(2) (1000 μatm), associated acidity (pH 7.83) and its feeding rates also increased correspondingly, except for the initial acclimating period, when it fed less. Our results imply that marine secondary producers increase their respiration and feeding rate in response to ocean acidification to balance the energy cost against increased acidity and CO(2) concentration. Copyright © 2012 Elsevier Ltd. All rights reserved.

Substances that interfere with guaiac card tests: implications for gastric aspirate testing.

PubMed

Gogel, H K; Tandberg, D; Strickland, R G

1989-09-01

Previous studies have shown that acidic pH and several ingestible substances can cause misleading guaiac tests of gastric aspirates. In this in vitro study, over 100 foods, beverages, and drugs were diluted to concentrations potentially present in the stomachs of outpatients being evaluated for gastrointestinal bleeding. These were mixed with known concentrations of blood and tested with different brands of guaiac cards. Decreased guaiac test sensitivity was associated with activated charcoal, dimethylaminoethanol, red chile, N-acetylcysteine, rifampin, red Jell-O (General Foods Corp, White Plains, NY), orange juice, Pepto-Bismol (Norwich Eaton Pharmaceuticals, Norwich, NY), simethicone, spaghetti sauce, and several red wines. Chlorophyll and methylene blue-containing tablets produced false-positive results, but other blue and blue-green colored tablets did not, except at high concentrations. Previously described false-negative results with vitamin C, bile, and certain antacids were confirmed, as were false-positive results with iodide, bromide, cupric sulfate, iron salts, and hypochlorite. Physicians should exercise caution when interpreting guaiac card tests of gastric aspirates, especially in the outpatient setting.

Potential impacts of historical disturbance on green turtle health in the unique & protected marine ecosystem of Palmyra Atoll (Central Pacific).

PubMed

McFadden, Katherine W; Gómez, Andrés; Sterling, Eleanor J; Naro-Maciel, Eugenia

2014-12-15

Palmyra Atoll, in the Central Pacific, is a unique marine ecosystem because of its remarkably intact food web and limited anthropogenic stressors. However during World War II the atoll was structurally reconfigured into a military installation and questions remain whether this may have impacted the health of the atoll's ecosystems and species. To address the issue we assessed green sea turtle (n=157) health and exposure to contaminants at this foraging ground from 2008 to 2012. Physical exams were performed and blood was sampled for testosterone analysis, plasma biochemistry analysis, hematology and heavy metal exposure. Hematological and plasma chemistries were consistent with concentrations reported for healthy green turtles. Heavy metal screenings revealed low concentrations of most metals, except for high concentrations of iron and aluminum. Body condition indices showed that <1% of turtles had poor body condition. In this study, we provide the first published blood values for a markedly healthy sea turtle population at a remote Central Pacific Atoll. Published by Elsevier Ltd.

Air quality during demolition and recovery activities in post-Katrina New Orleans.

PubMed

Ravikrishna, Raghunathan; Lee, Han-Woong; Mbuligwe, Stephen; Valsaraj, K T; Pardue, John H

2010-07-01

Air samples were collected during demolition and cleanup operations in the Lakeview district of New Orleans, Louisiana, USA, in late 2005 during the period immediately after Hurricane Katrina. Three different high-volume air samples were collected around waste collection areas that were created to temporarily hold the debris from the cleanup of residential properties in the area. Particulate concentrations were elevated and included crystalline fibers associated with asbestos. Metal concentrations on particulate matter resembled those measured in sediments deposited by floodwaters with the exception of Ba, which was elevated at all three locations. The highest organic contaminant concentration measured on particulates was the pesticide Ziram (Zinc, bis[diethylcarbamodithioato-S,S']-, [T-4]-) at 2,200 microg/g of particulate matter during sampling period 2. Ziram is used in latex paint, adhesives, caulking, and wallboard as a preservative. Fungal isolates developed from particulate air samples included species associated with disease including Aspergillus and Penicillium species. These data represent the most comprehensive assessment of demolition activities during the period immediately after Hurricane Katrina. Copyright (c) 2010 SETAC.

Increased central immunoreactive beta-endorphin content in patients with Wernicke-Korsakoff syndrome and in alcoholics.

PubMed Central

Summers, J A; Pullan, P T; Kril, J J; Harper, C G

1991-01-01

beta-endorphin, adrenocorticotrophin, and alpha-melanocyte stimulating hormone were measured by radioimmunoassay in three areas of human brain at necropsy in seven subjects with Wernicke-Korsakoff syndrome and in 52 controls. Thiamin concentration in six brain areas was also measured. Mamillary body beta-endorphin concentrations were significantly increased in those with the syndrome compared with controls, and those controls with high alcohol intake showed increased mamillary body beta-endorphin compared with controls with low alcohol intake. Brain thiamin concentration was similar in both groups, with the exception of the brainstem, where it was reduced in subjects with Wernicke-Korsakoff syndrome. Thalamic beta-endorphin in controls was inversely correlated with thiamin in frontal white matter, frontal cortex, parietal white matter and parietal cortex, while beta-endorphin in the hypothalamus of patients was inversely correlated with thiamin in frontal cortex, parietal white matter, thalamus and brainstem. These results suggest that there is a disturbance of the endorphinergic system in Wernicke-Korsakoff syndrome which may be related to alcohol intake. PMID:1650797

Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in Bowdoin National Wildlife Refuge and adjacent areas of the Milk River basin, northeastern Montana, 1986-87

USGS Publications Warehouse

Lambing, J.H.; Jones, W.E.; Sutphin, J.W.

1988-01-01

Concentrations of trace elements, radiochemicals, and pesticides in the Bowdoin National Wildlife Refuge lakes generally were not substantially larger than those in the water supplied from Dodson South Canal or in irrigation drainage. Concentrations of arsenic (47 micrograms/L), uranium (43 microg/L), and vanadium (51 microg/L) in Dry Lake Unit, and boron (1,000 microg/L) in Lake Bowdoin were notably larger than at other sites. Zinc concentrations in an irrigation drain (56 microg/L) and two shallow domestic wells (40 and 47 microg/L) were elevated relative to other sites. Concentrations of gross alpha radiation (64 picocuries/L) and gross beta radiation (71 picocuries/L) were elevated in Dry Lake Unit. Pesticides concentrations at all sites were 0.08 microg/L or less. Water use guidelines concentrations for boron, cadmium, uranium, zinc, and gross alpha radiation were slightly exceeded at several sites. In general, trace-constituent concentrations measured in the water do not indicate any potential toxicity problems in Bowdoin National Wildlife Refuge; however, highwater conditions in 1986 probably caused dilution of dissolved constituents compared to recent dry years. Trace element concentrations in bottom sediments of the refuge lakes were generally similar to background concentrations in the soils. The only exception was Dry Lake Unit, which had concentrations of chromium (99 micrograms/g), copper (37 microg/g), nickel (37 microg/g), vanadium (160 microg/g), and zinc (120 microg/g) that were about double the mean background concentrations. The maximum selenium concentration in bottom sediment was 0.6 microg/g. Pesticide concentrations in bottom sediments were less than analytical detection limits at all sites. With few exceptions, concentrations of trace elements and pesticides in biota generally were less than values known to produce harmful effects on growth or reproduction. (Lantz-PTT)

X-ray microanalysis of rotavirus-infected mouse intestine: A new concept of diarrhoeal secretion

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

Spencer, A.J.; Osborne, M.P.; Haddon, S.J.

1990-05-01

Neonatal mice were infected at 7 days of age with rotavirus (epizootic diarrhea of infant mice (EDIM) virus) and killed at 24-h intervals postinfection (PI). Cytoplasmic concentrations of Na, Mg, P, S, Cl, K, and Ca intestinal epithelial cells from infected and age-matched control animals were measured by x-ray microanalysis. In villus tip cells, Ca concentration increased at 24-96 h PI; Na concentration increased at 24-72 h PI; Ca and Na concentrations were near normal by 168 h PI. K concentration decreased 24-72 h PI, and Cl concentration decreased 48-96 h PI. In crypt cells, changes were observed without amore » discernible pattern: at 96 h PI, Na, Mg, S, and Cl concentrations increased and K concentration decreased; at 120 h PI, the concentrations of all elements except Na and Ca increased. In villus base cells, the mean concentrations of all elements except Ca peaked at 48-72 h PI and at 120 h PI. Na and Cl concentrations increased dramatically in some cells from 48 h PI onward. All the above concentration values were obtained from freeze-dried specimens and expressed in millimoles per kilogram of dry weight. Conversion of a limited number of data, pertaining to villus base cells, from dry weight to wet weight was possible. This conversion revealed that villus base cells in infected animals were more hydrated than corresponding cells from control animals. Also, the Na and Cl concentrations in mmol/kg H2O were significantly higher in villus base cells from infected animals than in those from corresponding controls: 137 +/- 7 versus 38 +/- 4 (Na) and 121 +/- 5 versus 89 +/- 6 (Cl). Wet weight concentrations of other elements were either the same (Mg) or lower (P, S, and K) after infection with virus.« less

Analysis of anabolic steroids in hair: time courses in guinea pigs.

PubMed

Shen, Min; Xiang, Ping; Yan, Hui; Shen, Baohua; Wang, Mengye

2009-09-01

Sensitive, specific, and reproducible methods for the quantitative determination of eight anabolic steroids in guinea pig hair have been developed using LC/MS/MS and GC/MS/MS. Methyltestosterone, stanozolol, methandienone, nandrolone, trenbolone, boldenone, methenolone and DHEA were administered intraperitoneally in guinea pigs. After the first injection, black hair segments were collected on shaved areas of skin. The analysis of these segments revealed the distribution of anabolic steroids in the guinea pig hair. The major components in hair are the parent anabolic steroids. The time courses of the concentrations of the steroids in hair (except methenolone, which does not deposit in hair) demonstrated that the peak concentrations were reached on days 2-4, except stanozolol, which peaked on day 10 after administration. The concentrations in hair appeared to be related to the physicochemical properties of the drug compound and to the dosage. These studies on the distribution of drugs in the hair shaft and on the time course of their concentration changes provide information relevant to the optimal time and method of collecting hair samples. Such studies also provide basic data that will be useful in the application of hair analysis in the control of doping and in the interpretation of results.

Effect of air temperature and humidity on ingestive behaviour of sheep

NASA Astrophysics Data System (ADS)

Paranhos da Costa, Mateus J. R.; da Silva, Roberto Gomes; de Souza, Roberto Carlos

1992-12-01

Thirty-two Polwarth ewes, of ages up to 1 year, were observed in a climatic chamber (24 to 45° C) for eight periods of 5 h each. The observations were made through a window in the chamber wall. All animals were observed four times, then shorn and observed four times again. The animals were given weighed quantities of water and feed consisting of commercial concentrate plus Rhodes grass ( Chloris gayana) hay. The water and feed remaining after 5 h of observation were weighed. The following traits were analysed: time eating hay (TEH), time eating concentrate (TEC), time drinking water (TDW), weight of hay eaten (WHE), weight of concentrate eaten (WCE), volume of ingested water (VIW), ruminating time standing up (RTS), ruminating time lying down (RTL), idling time standing up (ITS), and idling time lying down (ITL). Shearing had a significant effect for all traits except ITS. Shearing resulted in higher values for all traits except for ITS and ITL. Ingestion of hay (TEH and WHE) decreased with increased air temperature and humidity, while the ingestion of concentrate (TEC) and WHE) and water (TDW and VIW) increased. Rumination decreased with increased air temperature and humidity, and was higher in shorn than in unshorn sheep.

Long term stability of Li-S batteries using high concentration lithium nitrate electrolytes

DOE PAGES

Adams, Brian D.; Carino, Emily V.; Connell, Justin G.; ...

2017-09-08

The lithium-sulfur (Li-S) battery is a very promising candidate for the next generation of energy storage systems required for electrical vehicles and grid energy storage applications due to its very high theoretical specific energy (2500 W h kg -1). However, low Coulombic efficiency (CE) during repeated Li metal plating/stripping has severely limited the practical application of rechargeable Li-S batteries. In this work, a new electrolyte system based on a high concentration of LiNO 3 in diglyme (G2) solvent is developed which enables an exceptionally high CE for Li metal plating/stripping and thus high stability of the Li anode in themore » sulfur-containing electrolyte. The tailoring of electrolyte properties for the Li anode has proven to be a highly successful strategy for improving the capacity retention and cycle life of Li-S batteries. This electrolyte provides a CE of greater than 99% for over 200 cycles of Li plating/stripping. In contrast, the Li anode cycles for less than 35 cycles (with a high CE) in the state-of-the-art 1 M LiTFSI + 0.3 M LiNO 3 in 1,3-dioxolane:1,2-dimethoxyethane (DOL:DME) electrolyte under the same conditions. Lastly, the stable Li anode enabled by the new electrolyte may accelerate the applications of high energy density Li-S batteries in both electrical vehicles and large-scale grid energy storage markets.« less

Long term stability of Li-S batteries using high concentration lithium nitrate electrolytes

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

Adams, Brian D.; Carino, Emily V.; Connell, Justin G.

The lithium-sulfur (Li-S) battery is a very promising candidate for the next generation of energy storage systems required for electrical vehicles and grid energy storage applications due to its very high theoretical specific energy (2500 W h kg -1). However, low Coulombic efficiency (CE) during repeated Li metal plating/stripping has severely limited the practical application of rechargeable Li-S batteries. In this work, a new electrolyte system based on a high concentration of LiNO 3 in diglyme (G2) solvent is developed which enables an exceptionally high CE for Li metal plating/stripping and thus high stability of the Li anode in themore » sulfur-containing electrolyte. The tailoring of electrolyte properties for the Li anode has proven to be a highly successful strategy for improving the capacity retention and cycle life of Li-S batteries. This electrolyte provides a CE of greater than 99% for over 200 cycles of Li plating/stripping. In contrast, the Li anode cycles for less than 35 cycles (with a high CE) in the state-of-the-art 1 M LiTFSI + 0.3 M LiNO 3 in 1,3-dioxolane:1,2-dimethoxyethane (DOL:DME) electrolyte under the same conditions. Lastly, the stable Li anode enabled by the new electrolyte may accelerate the applications of high energy density Li-S batteries in both electrical vehicles and large-scale grid energy storage markets.« less

Long term stability of Li-S batteries using high concentration lithium nitrate electrolytes

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

Adams, Brian D.; Carino, Emily V.; Connell, Justin G.

The lithium-sulfur (Li-S) battery is a very promising candidate for the next generation of energy storage systems required for electrical vehicles and grid energy storage applications due to its very high theoretical specific energy (2500 W h kg(-1)). However, low Coulombic efficiency (CE) during repeated Li metal plating/stripping has severely limited the practical application of rechargeable Li-S batteries. In this work, a new electrolyte system based on a high concentration of LiNO3 in diglyme (G2) solvent is developed which enables an exceptionally high CE for Li metal plating/stripping and thus high stability of the Li anode in the sulfur-containing electrolyte.more » The tailoring of electrolyte properties for the Li anode has proven to be a highly successful strategy for improving the capacity retention and cycle life of Li-S batteries. This electrolyte provides a CE of greater than 99% for over 200 cycles of Li plating/stripping. In contrast, the Li anode cycles for less than 35 cycles (with a high CE) in the state-of-the-art 1 M LiTFSI + 0.3 M LiNO3 in 1,3-dioxolane: 1,2-dimethoxyethane (DOL:DME) electrolyte under the same conditions. The stable Li anode enabled by the new electrolyte may accelerate the applications of high energy density Li-S batteries in both electrical vehicles and large-scale grid energy storage markets.« less

Spatial and temporal distribution of specific conductance, boron, and phosphorus in a sewage-contaminated aquifer near Ashumet Pond, Cape Cod, Massachusetts

USGS Publications Warehouse

Bussey, K.W.; Walter, D.A.

1996-01-01

Spatial and temporal distributions of specific conductance, boron, and phosphorus were determined in a sewage-contaminated sand and gravel aquifer near Ashumet Pond, Cape Cod, Massachusetts. The source of contamination is secondarily treated sewage that has been discharged onto rapid- infiltration sand beds at the Massachusetts Military Reservation since 1936. Contaminated ground water containing as much as 2 milligrams per liter of dissolved phosphorus is discharging into Ashumet Pond, and there is concern that the continued discharge of phosphorus into the pond will accelerate eutrophication of the pond. Water-quality data collected from observation wells and multilevel samplers from June through July 1995 were used to delineate the spatial distributions of specific conductance, boron, and phosphorus. Temporal distributions were determined using sample-interval-weighted average concen- trations calculated from data collected in 1993, 1994, and 1995. Specific conductances were greater than 400 microsiemens per centimeter at 25C as far as 1,200 feet downgradient from the infiltration beds. Boron concentrations were greater than 400 micrograms per liter as far as 1,800 feet down- gradient from the beds and phosphorus concen- trations were greater than 3.0 milligrams per liter as far as 1,200 feet from the beds. Variability in distributions of specific conductance and boron concentrations is attributed to the history and distribution of sewage disposal onto the infiltration beds. The distribution of phosphorus concentrations also is related to the history and distribution of sewage disposal onto the beds but additional variability is caused by chemical interactions with the aquifer materials. Temporal changes in specific conductance and boron from 1993 to 1995 were negligible, except in the lower part of the plume (below an altitude of about 5 feet above sea level), where changes in weighted-average specific conductance were greater than 100 microsiemens per centimeter at 25C. Temporal changes in phosphorus generally were small except in the lower part of the plume, where weighted-average phosphorus concentrations decreased more than 1.3 milligrams per liter from 1993 to 1994. This decrease was accompanied by an increase in specific conductance. High concen- trations of phosphorus associated with low and moderate specific conductances possibly are the result of rapid phosphorus desorption in response to an influx of uncontaminated ground water. As a result of the cessation of sewage disposal in December 1995, clean, oxygenated water moving into contaminated parts of the aquifer may cause rapid desorption of sorbed phosphorus and temporarily result in high dissolved phosphorus concentrations in the aquifer.