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Sample records for 40k activity concentration

  1. Determination of (238)U, (232)Th and (40)K activity concentrations in riverbank soil along the Chao Phraya river basin in Thailand.

    PubMed

    Santawamaitre, T; Malain, D; Al-Sulaiti, H A; Bradley, D A; Matthews, M C; Regan, P H

    2014-12-01

    The activity concentrations of (238)U, (232)Th and (40)K in riverbank soil along the Chao Phraya river basin was determined through gamma-ray spectrometry measurements made using a hyper-pure germanium detector in a low background configuration. The ranges of activity concentrations of (238)U, (232)Th and (40)K were found to be 13.9 ↔ 76.8, 12.9 ↔ 142.9 and 178.4 ↔ 810.7 Bq kg(-1), respectively. The anthropogenic radionuclide, (137)Cs, was not observed in statistically significant amounts above the background level in the current study. The absorbed gamma dose rate in air at 1 m above the ground surface, the outdoor annual effective dose equivalent, the values of the radium equivalent activity and the external hazard index associated with all the soil samples in the present work were evaluated. The results indicate that the radiation hazard from primordial radionuclides in all soil samples from the area studied in this current work is not significant. PMID:25195170

  2. Activity concentrations of 226Ra, 232Th, 40K and 137Cs radionuclides in Turkish medicinal herbs, their ingestion doses and cancer risks

    NASA Astrophysics Data System (ADS)

    Parmaksız, Aydın; Ağuş, Yusuf

    2014-11-01

    Twenty-two medicinal herb samples, each representing a distinct species, were collected from Turkish markets and measured by the gamma spectrometric method. The activity concentration of 226Ra in medicinal herbs was found in the range of minimum detectable activity (MDA) and 15.1 ± 2.2 Bqkg-1. The activity concentration of 232Th ranged from MDA values to 3.5 ± 0.8 Bqkg-1. The activity concentration of 40K varied between 50.0 ± 16.8 and 1311.5 ± 57.3 Bqkg-1. All 137Cs activity concentrations of medicinal herbs were found to have lower than MDA values. The bone surface dose, lower large intestine and colon doses were found to be 182.9, 18.8 and 18.7 µSvy-1, respectively. The highest committed effective dose originated from the annual ingestion of 1 kg medicinal herb was calculated notably low as 9.0 µSv. The cancer risk of ingestion of medicinal herbs was found to be small enough to be neglected. The selected Turkish medicinal herbs are considered safe for human consumption.

  3. Activity concentration measurements of 137Cs, 90Sr and 40K in a wild food matrix reference material (Wild Berries) CCRI(II)-S8

    NASA Astrophysics Data System (ADS)

    Wätjen, U.; Altzitzogloa, T.; Ceccatelli, A.; Dikmen, H.; Ferreux, L.; Frechou, C.; García, L.; Gündogdu, G.; Kis-Benedek, G.; La Rosa, J.; Luca, A.; Moreno, Y.; Oropesa, P.; Pierre, S.; Schmiedel, M.; Spasova, Y.; Szücs, L.; Vasile, M.; Wershofen, H.; Yücel, Ü.

    2014-01-01

    In 2009, the CCRI approved a supplementary comparison to be organized by the IRMM as pilot laboratory for the activity concentrations of 137Cs, 90Sr and 40K in a matrix material of dried bilberries. The organization of this comparison and the material and measurement methods used are described. The supplementary comparison reference values (SCRV) for each of the three radionuclides are given together with the degrees of equivalence of each participating laboratory with the SCRV for the specific radionuclide. The results of this supplementary comparison allow the participating NMIs/designated institutes to declare calibration and measurement capabilities (CMCs) for the given radionuclides in a similar type of food matrix, an important aspect given the relatively few supplementary comparisons for activity in matrix materials organized so far. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  4. Determination of 40K, 232Th and 238U activity concentrations in ambient PM2.5 aerosols and the associated inhalation effective dose to the public in Jeddah City, Saudi Arabia.

    PubMed

    Zytoon, Mohamed A; Aburas, Hani M; Abdulsalam, Mohammed I

    2014-03-01

    Natural radioactivity of soil samples has been studied in many countries of the Arabian Peninsula, including Saudi Arabia. Radiological indices based on soil radioactivity have been widely used in these studies. However, there are no available data about natural radioactivity of fine aerosol particles in such countries. The objective of this study is to determine the activity concentrations of (40)K, (232)Th and (238)U in airborne PM2.5 and the associated internal inhalation radiation dose to the public in Jeddah City, Saudi Arabia. Twenty-four air samples in four locations throughout Jeddah were collected and analyzed for PM2.5 and the associated K, Th and U. The activity concentrations of the isotopes (40)K, (232)Th and (238)U were calculated. High atmospheric PM2.5 concentrations (mean: 50.81 ± 34.02 μg/m(3)) were found. The natural radioactivity associated with PM2.5 due to the isotopes (40)K, (232)Th and (238)U were 301.8 ± 76.1, 11.8 ± 4.2 and 10.8 ± 3.4 Bq/kg, respectively, and the Raeq was calculated as 44.9 ± 14.0 Bq/kg. The inhalation annual effective radiation dose to the public due to natural isotopes of the airborne PM2.5 was in the range 15.03-58.87 nSv/year, depending on the age group. Although these dose values were associated with the PM2.5 fraction only, they were higher than the world references values in air reported in the UNSCEAR, 2000 report. PMID:24462924

  5. 235U, 238U, 232Th, 40K and 137Cs activity concentrations in marine sediments along the northern coast of Oman Sea using high-resolution gamma-ray spectrometry.

    PubMed

    Zare, Mohammad Reza; Mostajaboddavati, Mojtaba; Kamali, Mahdi; Abdi, Mohammad Reza; Mortazavi, Mohammad Seddigh

    2012-09-01

    The natural radioactivity levels in sediment samples of the northern coast of Oman Sea, covering the coastal strip from Hormoz canyon to Goatr seaport, as the first time has been determined. The results of measurements will serve as background reference level for Oman Sea coastlines. Sediments from 36 coastal and near shore locations were collected for analysis. Analysis on the collected samples were carried out to determine (235)U, (238)U, (232)Th, (40)K and (137)Cs using two high purity germanium detectors with 38.5% and 55% relative efficiencies. The concentration of (235)U, (238)U, (232)Th, (40)K and (137)Cs in sediment samples ranged between 1.01 and 2.87 Bq/kg, 11.83 and 22.68 Bq/kg, 10.7 and 25.02 Bq/kg, 222.89 and 535.07 Bq/kg and 0.14 and 2.8 Bq/kg, respectively. The radium equivalent activity was well below the defined limit of 370 Bq/kg. The external hazard indices were found to be less than 1, indicating a low dose. PMID:22717321

  6. Determination of (226)Ra, (232)Th, (40)K, (235)U and (238)U activity concentration and public dose assessment in soil samples from bauxite core deposits in Western Cameroon.

    PubMed

    Mekongtso Nguelem, Eric Jilbert; Moyo Ndontchueng, Maurice; Motapon, Ousmanou

    2016-01-01

    Determination of activity concentrations in twenty five (25) soil samples collected from various points in bauxite ore deposit in Menoua Division in Western of Cameroon was done using gamma spectrometry based Broad Energy Germanium (BEGe6530) detector. The average terrestrial radionuclides of (40)K, (226)Ra, (232)Th, (235)U and (238)U were measured as 671 ± 272, 125 ± 58, 157 ± 67, 6 ± 3 and 99 ± 69 Bq kg(-1), respectively. The observed activity concentrations of radionuclides were compared with other published values in the world. The outdoor absorbed dose rate in air varied from 96.1 to 321.2 nGy h(-1) with an average of 188.2 ± 59.4 nGy h(-1). The external annual effective dose rate and external hazard index were estimated as 0.23 ± 0.07 mSv year(-1) for outdoor, 0.92 ± 0.29 mSv year(-1) for indoor and 1.13 for the external hazard index, respectively. These radiological safe parameters were relatively higher than the recommended safe limits of UNSCEAR. Consequently, using of soil as building material might lead to an increase the external exposure to natural radioactivity and future applications research need to be conducted to have a global view of radioactivity level in the area before any undergoing bauxite ore exploitation. PMID:27536536

  7. Activity levels of 137Cs and 40K in the skin and the cutaneous organs of a cow.

    PubMed

    Pichl, Elke; Rabitsch, Herbert

    2003-08-01

    We have performed an extensive study to determine the activity distributions of radiocesium (137Cs) and of the radioisotope 40K of potassium in the whole body of a cow. ICRP assumes that cesium and potassium are distributed homogeneously throughout the whole body of an organism. The current investigation measured concentrations of 137Cs and 40K in components of the skin, horns, and hooves of a cow. Activity levels of 137Cs were caused by the long-term ingestion following the Chernobyl fallout, whereas the naturally occurring potassium (40K) is an essential part of cow's normal diet. The cow was born at the time of the fallout following the Chernobyl accident and had ingested heavily contaminated forage during its entire lifetime. Activities of 137Cs and 40K were determined simultaneously by gamma spectrometry. All activities are related to the day of slaughter and include also corrections for self attenuation of photons caused by the different densities of the samples. Radionuclide concentrations in samples were corrected for moisture losses incurred during freezing and sample preparation. Surface contamination on the skin was estimated by rinsing it in heated water followed by removal of the epidermis and hair. In comparison with the activities of the components of the skin we observed a considerable amount of external contamination on the surface of the skin. But with respect to whole body countings of the animal this amount of external contamination appears to be negligible. It was found that activity ratios of 137Cs to 40K are greater than 1 in all measured components. The average activity concentrations of 137Cs and 40K in the common integument are 23.3 Bq kg(-1) and 13.3 Bq kg(-1), respectively. The highest activity concentrations of 137Cs and 40K were measured in clean hair and hypodermis. Despite being its largest organ, the cow's skin contains probably less than 1% of the animal's whole body 137Cs activity. PMID:12938962

  8. Activity size distributions of some naturally occurring radionuclides 7Be, 40K and 212Pb in indoor and outdoor environments.

    PubMed

    Mohamed, A

    2005-05-01

    The activity size distributions of natural radionuclides (7)Be and (40)K were measured outdoor in El-Minia city, Egypt by means of gamma spectroscopy. A low-pressure Berner cascade impactor was used as a sampling device. The activity size distribution of both (7)Be and (40)K was described by one log-normal distribution, which was represented by the accumulation mode. The activity median aerodynamic diameter (AMAD) of (7)Be and (40)K was determined to be 530 and 1550 nm with a relative geometric standard deviation (delta, which was defined as the dispersion of the peak) of 2.4 and 2, respectively. The same sampling device (Berner impactor) and a screen diffusion battery were used to measure the activity size distribution, activity concentration and unattached fraction (f(P)) of (212)Pb in indoor air of El-Minia City, Egypt. The mean activity median aerodynamic diameter (AMAD) of the accumulation mode for attached (212)Pb was determined to be 250 nm with a mean geometric standard deviation (delta) of 2.6. The mean value of the specific concentration of (212)Pb associated with that mode was determined to be 460+/-20 mBq m(-3). The activity median thermodynamic diameter (AMTD) of unattached (212)Pb was determined to be 1.25 nm with delta of 1.4. A mean unattached fraction (f(p)) of 0.13+/-0.02 was obtained at a mean aerosol particle concentration of 1.8 x 10(3) cm(-3). The mean activity concentration of unattached (212)Pb was found to be 19+/-3 mBq m(-3). It was found that the aerosol concentration played an important role in varying the unattached, attached activity concentration and unattached fraction (f(P)). PMID:15763482

  9. The Concentrations of {sup 40}K, {sup 226}Ra and {sup 232}Th in Soil Sample in Osmaniye (Turkey)

    SciTech Connect

    Akkurt, I.; Guenoglu, K.; Kara, A.; Mavi, B.; Karaboerklue, S.

    2011-12-26

    The {sup 40}K, {sup 226}Ra and {sup 232}Th concentration is due to the magmatic structure of the earth and it can be varied from place to place. Osmaniye is located in the Eastern side of Mediteranean Region. It holds the climatic characteristics of the same region and arises with Middle Taurus Mountains from west to North and with Amonos Mounations in East and West-east parts and is situated between 35 deg. .52'-36 deg. .42' east longitudes and 36 deg. .57'-37 deg. .45' north latitudes. In this study, the natural radioactivity concentrations {sup 40}K, {sup 226}Ra and {sup 232}Th in some soil samples collected in Osmaniye have been investigated. The measurements have been performed using 3x3{sup ''} NaI(Tl) detector system.

  10. Measurement of 226Ra, 232Th, 137Cs and 40K activities of Wheat and Corn Products in Ilam Province – Iran and Resultant Annual Ingestion Radiation Dose

    PubMed Central

    CHANGIZI, Vahid; SHAFIEI, Elham; ZAREH, Mohammad Reza

    2013-01-01

    Background: Background: Natural background radiation is the main source of human exposure to radioactive material. Soils naturally have radioactive mineral contents. The aim of this study is to determine natural (238 U, 232 Th, 40 K) and artificial (137 Cs) radioactivity levels in wheat and corn fields of Eilam province. Methods: HPGe detector was used to measure the concentration activity of 238 U and 232 Th series, 40 K and 137 Cs in wheat and corn samples taken from different regions of Eilam province, in Iran. Results: In wheat and corn samples, the average activity concentrations of 226 Ra, 232 Th, 40 K and 137 Cs were found to be 1, 67, 0.5, 91.73, 0.01 and 0.81, 0.85, 101.52, 0.07 Bq/kg (dry weight), respectively. H ex and H in in the present work are lower than 1. The average value of H ex was found to be 0.02 and 0.025 and average value of H in to be found 0.025 and 0.027 in wheat fields samples and corn samples in Eilam provinces, respectively. The obtained values of AGDE are 30.49 mSv/yr for wheat filed samples and 37.89 mSv/yr for corn samples; the AEDE rate values are 5.28 mSv/yr in wheat filed samples and this average value was found to be 6.13 mSv/yr in corn samples in Eilam. Transfer factors (TFs) of long lived radionuclide such as 137 Cs, 226 Ra, 232 Th and 40 K from soils to corn and wheat plants have been studied by radiotracer experiments. Conclusion: The natural radioactivity levels in Eilam province are not at the range of high risk of morbidity and are under international standards. PMID:26056646

  11. Concentrations of {sup 137}Cs and {sup 40}K in edible mushrooms collected in Japan and radiation dose due to their consumption

    SciTech Connect

    Ban-nai, Tadaaki; Muramatsu, Yasuyuki; Yoshida, Satoshi

    1997-03-01

    To estimate radiocesium intake due to eating mushrooms, about 100 samples belonging to 11 species were analyzed to establish to establish representative values for {sup 137}Cs and {sup 40}K in common edible mushrooms available in food markets. Concentration ranges were <0.047-39 Bq kg{sup -1} (wet wt) for {sup 137}Cs and 30-210 Bq kg{sup -1} (wet wt) for {sup 40}K. The median concentrations were 1.3 Bq kg{sup -1} (wet wt) for {sup 137}Cs and 97 Bq kg{sup -1} (wet wt) for {sup 40}K. The {sup 137}Cs concentration is cultivated mushrooms were markedly lower than those in wild mushrooms. The annual intake of {sup 137}Cs per person through mushrooms was calculated (using analytical results and food consumption data in Japan) to be 6.0 Bq for {sup 137}Cs, which is about 32% of the total dietary intake of this nuclide. The effective dose equivalent of {sup 137}Cs through mushroom was estimated to be 7.7 X 10{sup -8} Sv (range estimated from the standard deviation: 3.0 x 10{sup -8}-1.0 x 10{sup -7}). 19 refs., 1 fig., 2 tabs.

  12. Vertical Profiles Of {sup 226}Ra, {sup 232}Th And {sup 40}K Activities In Rocks From The Irati Formation Of The Parana Sedimentary Basin, Southern Brazil

    SciTech Connect

    Ferreira, Ademar de O.; Bastos, Rodrigo O.; Appoloni, Carlos R.

    2008-08-07

    Naturally occurring radioisotopes are present in different concentrations in sedimentary rocks, reflecting the origin of the sediments, the depositional environment, and more recent events such as weathering and erosion. Using a high-resolution {gamma}-ray spectrometry methodology, sedimentary rocks were measured to assess the concentration activities of the natural radioisotopes. The surveyed rocks are from the Irati formation in the Parana sedimentary basin, which are exposed by an abandoned, open-pit limestone mine, in the city of Sapopema, southern Brazil. The exposed vertical profile is 5 m, and its stratigraphy is represented by an alternation of limestone and bituminous shale (layers being a few decimeters thick), and some millimeter rhythm layers with limestone and bituminous shale laminas. Eleven samples were collected along this profile, each of them dried in the open air during 48 hours, sieved through 4 mm mesh and sealed in cylindrical recipients. Measurements were accomplished using a 66% relative efficiency HPGE detector connected to a standard gamma ray spectrometry electronic chain. The detector efficiency in the range of 60 to 1800 keV was carried out with the certified IAEA-385 sediment sample. The Lower Limit of Detection (LLD) to the system is 2.40 Bq{center_dot}kg{sup -1} for {sup 226}Ra, 1.84 Bq{center_dot}kg{sup -1} for {sup 232}Th and 4.20 Bq{center_dot}kg{sup -1} for {sup 40}K. Activity concentrations were determined for {sup 226}Ra (from 16.22 to 151.55 Bq{center_dot}kg{sup -1}), {sup 232}Th (from 2.93 to 56.12 Bq{center_dot}kg{sup -1}) and {sup 40}K (from 38.45 to 644.63 Bq{center_dot}kg{sup -1}). The layers enriched with organic matter presented the higher values of activity. The measured concentrations of the natural radioisotopes were lower for limestone samples (average values and respective deviations were 22.81{+-}0.22 Bq{center_dot}kg{sup -1} for {sup 226}Ra, 4.21{+-}0.07 Bq{center_dot}kg{sup -1} for {sup 232}Th, and 50

  13. Investigation of (235)U, (226)Ra, (232)Th, (40)K, (137)Cs, and heavy metal concentrations in Anzali international wetland using high-resolution gamma-ray spectrometry and atomic absorption spectroscopy.

    PubMed

    Zare, Mohammad Reza; Kamali, Mahdi; Fallahi Kapourchali, Maryam; Bagheri, Hashem; Khoram Bagheri, Mahdi; Abedini, Ali; Pakzad, Hamid Reza

    2016-02-01

    Measurements of natural radioactivity levels and heavy metals in sediment and soil samples of the Anzali international wetland were carried out by two HPGe-gamma ray spectrometry and atomic absorption spectroscopy techniques. The concentrations of (235)U, (226)Ra, (232)Th, (40)K, and (137)Cs in sediment samples ranged between 1.05 ± 0.51-5.81 ± 0.61, 18.06 ± 0.63-33.36 ± .0.34, 17.57 ± 0.38-45.84 ± 6.23, 371.88 ± 6.36-652.28 ± 11.60, and 0.43 ± 0.06-63.35 ± 0.94 Bq/kg, while in the soil samples they vary between 2.36-5.97, 22.71-38.37, 29.27-42.89, 472.66-533, and 1.05-9.60 Bq/kg for (235)U, (226)Ra, (232)Th, (40)K, and (137)Cs, respectively. Present results are compared with the available literature data and also with the world average values. The radium equivalent activity was well below the defined limit of 370 Bq/kg. The external hazard indices were found to be less than 1, indicating a low dose. Heavy metal concentrations were found to decrease in order as Fe > Mn > Sr > Zn > Cu > Cr > Ni > Pb > Co > Cd. These measurements will serve as background reference levels for the Anzali wetland. PMID:26490904

  14. Accumulation and translocation peculiarities of (137)Cs and (40)K in the soil--plant system.

    PubMed

    Marčiulionienė, Danutė; Lukšienė, Benedikta; Jefanova, Olga

    2015-12-01

    Long-term investigations (1996-2008) were conducted into the (137)Cs and (40)K in the soil of forests, swamps and meadows in different regions of Lithuania, as well as in the plants growing in these media. The (137)Cs and (40)K activity concentrations, the (137)Cs/(40)K activity concentration ratio and accumulation, and translocation in the system, i.e. from the soil to plant roots to above-ground plant part of these radionuclides, were evaluated after gamma-spectrometric measurements using a high purity germanium (HPGe) detector. Based on the obtained data, it can be asserted that in the tested plant species, the (137)Cs and (40)K accumulation, the transfer from soil to roots and translocation within the plants depend on the plant species and environmental ecological conditions. The (137)Cs/(40)K activity concentration ratios in the same plant species in different regions of Lithuania are different and this ratio depends on the biotope (forest, swamp or meadow) in which the plant grows and on the location of the growing region. Based on the determined trends of statistically reliable inverse dependence between the activity concentrations in both soil and plants, it can be stated that the exchange of (137)Cs and (40)K in plants and soil is different. Different accumulations and translocations of investigated radionuclides in the same plant species indicate diverse biological metabolism of (137)Cs and its chemical analogue (40)K in plants. A competitive relationship exists between (137)Cs and (40)K in plants as well as in the soil. PMID:26301832

  15. Curtiss P-40K Warhawk

    NASA Technical Reports Server (NTRS)

    1943-01-01

    Curtiss P-40K Warhawk: The Curtiss P-40K Warhawk was an improved version of the P-40E. This Warhawk was used by the NACA at Langley from July of 1942 until October of 1944. The P-40 gained most of its fame as the mount of the American Volunteer Group (AVG) 'Flying Tigers.' But shark mouthed P-40s were also flown by the Royal Air Force in North Africa.

  16. 137Cs and 40K in some traditional herbal teas collected in the mountain regions of Serbia.

    PubMed

    Mitrović, Branislava M; Grdović, Svetlana N; Vitorović, Gordana S; Vitorović, Duško P; Pantelić, Gordana K; Grubić, Goran A

    2014-01-01

    Herbal teas are an important part of traditional medicine in Serbia. The objective of the present study was to determine the activity concentrations of (40)K and (137)Cs in herbal tea, using the gamma spectroscopy method. The samples were collected during the period 2011-2012 in three mountain regions in Western and Central Serbia. The activity concentrations of (40)K and (137)Cs were found to be in the range of 130-1160 and 0.7-124 Bq kg(-1), respectively. The average annual effective dose equivalents from ingestion of (40)K and (137)Cs for an adult person consuming one cup of herbal tea daily were found to be 588.4-5250.2 nSv for (40)K and 4.0-706.1 nSv for (137)Cs. Our investigation showed that the herbal teas originating from Maljen, Zlatibor and Tara mountains are radiologically safe for human consumption. PMID:25322769

  17. The influence of particle size on radionuclide activity concentrations in Tejo River sediments.

    PubMed

    Madruga, M J; Silva, L; Gomes, A R; Libânio, A; Reis, M

    2014-06-01

    Sediment samples from Tejo River were analyzed for (228)Ra, (226)Ra, (137)Cs and (40)K by HPGe gamma spectrometry. The activity concentration data were statistically analyzed. The activity concentrations values were in the range of about two orders of magnitude for each radionuclide. The influence of the particle size on the radionuclide concentrations was observed. The different environmental origins of the radionuclides (228)Ra, (226)Ra, (137)Cs and (40)K, in the sediments were demonstrated through correlation analysis. Cluster analysis showed a close relationship between (228)Ra and (226)Ra and a different behavior for (40)K. The data obtained in this study provides useful information on the background radioactivity of the studied area and can be further used for radiological mapping of the Tejo River. PMID:24561724

  18. Life-long accumulation of 137Cs and 40K in the vertebral column of a cow.

    PubMed

    Pichl, Elke; Rabitsch, Herbert

    2013-01-01

    We have investigated the accumulation of (137)Cs and (40)K in all the tissues and organs of an adult slaughtered Austrian "mountain pasture cow". In this paper we present measured (137)Cs- and (40)K-activity concentrations in different tissues of the vertebral bodies, in their other bony components and in all the vertebrae forming the vertebral column. Data are also given for activity concentrations of adherent tissues, and for activities of both the components and the whole vertebral column. The dairy cow was born in a highly contaminated region of Styria, Austria, at the time of the radioactive fallout following the Chernobyl accident. Both radionuclides were incorporated during life-long ingestion and their accumulation in all the vertebrae up to the day of slaughtering was determined by high-purity germanium detectors. Our results show considerable variations of (137)Cs- and (40)K-activity concentrations in the components of a certain vertebra, within vertebrae of a particular region, and between vertebrae of different regions of the vertebral column. Particularly, the courses of (137)Cs- and (40)K-activity concentrations in trabecular bone, cortical bone and intervertebral discs of thoracic vertebral bodies are subdivided by a strong drop into two sections. Mean values of (137)Cs-concentration in vertebral bodies of these subsections vary by a factor 4. Compared with corresponding quantities for the skeleton, total mass, as well as total (137)Cs- and (40)K-activities of the whole vertebral column came to 14%, and approximately 38% for each (137)Cs and (40)K, respectively. PMID:22943884

  19. Studies on radionuclides 228Ra, 238U, 228Th and 40K in selected seaweeds of coastal Tamil Nadu, India.

    PubMed

    Saroja, P Mary; Immanuel, G; Raj, G Allen Gnana; Selvan, K Esai

    2012-09-01

    Studies on natural and anthropogenic radioactivity assume greater importance in the context of human health and development. Hence two species of seaweeds viz: Gracilaria edulis and Ulva lactuca, from three high background radiation areas (Arockiapuram, Kadiapattinam and Kurumpanai) on the southwest coast of Tamil Nadu, and Mandapam as low background radiation area of the southeast coast of Tamil Nadu were studied for variations in activity concentration of 228Ra, 40K, 238U and 228Th. Among these radionuclides, 40K recorded significant inter-species variation while 238 U and 228Th showed significant association. The overall mean concentration of radionuclides was found high in G. edulis (5.31,57.49,36.05,356.55 Bq kg(-1) for 228Ra, 40K, 238U, 228Th respectively), while the mean concentrations for U. lactuca were 4.88, 42.35, 34.40,347.70 Bqkg(-1) for 228Ra, 40K, 238U, 228Th respectively. The mean concentration of radionuclides was uniformly found low during northeast monsoon season in both the seaweed species. PMID:23734458

  20. Non-destructive determination of uranium, thorium and 40K in tobacco and their implication on radiation dose levels to the human body.

    PubMed

    Landsberger, S; Lara, R; Landsberger, S G

    2015-11-01

    The naturally occurring radionuclides of (235)U, (238)U and (232)Th and their daughter products are a potential major source of anthropogenic radiation to tobacco smokers. Often overlooked is the presence of (40)K in tobacco and its implication to radiation dose accumulation in the human body. In this study, these three radiation sources have been determined in four typical US cigarettes using neutron activation analysis (NAA). The NAA reactions of (238)U(n,γ)(239)U, (232)Th(n,γ)(233)Th and (41)K(n,γ)(42)K were used to determine (235)U, (238)U and (232)Th and (40)K, respectively. The activity of (238)U can easily be determined by epithermal NAA of the (238)U(n,γ)(239)U reaction, and the activity of (235, 234)U can easily be deduced. Using isotopic ratios, the activity due to (40)K was found by the determined concentrations of (41)K (also by epithermal neutrons) in the bulk material. Each gram of total potassium yields 30 Bq of (40)K. The annual effective dose for smokers using 20 cigarettes per day was calculate to be 14.6, 137 and 9 μSv y(-1) for (238,235,) (234)U, (232)Th and (40)K, respectively. These values are significantly lower that the dose received from (210)Po except for (232)Th. PMID:25944955

  1. (137)Cs, (40)K and (210)Po in marine mammals from the southern Baltic Sea.

    PubMed

    Ciesielski, Tomasz; Góral, Marta; Szefer, Piotr; Jenssen, Bjørn Munro; Bojanowski, Ryszard

    2015-12-15

    This study provides information on baseline concentrations of the radionuclides Cesium-137, Potassium-40 and Polonium-210 in sea mammals from the Baltic Sea. The radionuclides were analyzed in the liver, kidney and muscle of harbor porpoises, striped dolphins, and gray and ringed seals from the Polish coast by γ- and α-spectrometry. Median (137)Cs activities were 14.8, 13.2 and 23.2 Bq kg(-1) w.w. in the liver, kidney and muscles, respectively. Activities of (40)K and (210)Po in the respective tissues were found to be 79.1, 79.8 and 111 Bq kg(-1) for (40)K and 58.1, 59.2 and 32.9 Bq kg(-1) for (210)Po. The measured (137)Cs concentrations were extraordinarily high in comparison to those reported in sea mammals from other locations. However, dose assessments did not imply health effects from (137)Cs exposure in Baltic Sea mammals. Correlations between (137)Cs tissue activities and reported sea water concentrations highlight the potential use of marine mammals for biomonitoring purposes. PMID:26456908

  2. High-spin structure in 40K

    NASA Astrophysics Data System (ADS)

    Söderström, P.-A.; Recchia, F.; Nyberg, J.; Gadea, A.; Lenzi, S. M.; Poves, A.; Ataç, A.; Aydin, S.; Bazzacco, D.; Bednarczyk, P.; Bellato, M.; Birkenbach, B.; Bortolato, D.; Boston, A. J.; Boston, H. C.; Bruyneel, B.; Bucurescu, D.; Calore, E.; Cederwall, B.; Charles, L.; Chavas, J.; Colosimo, S.; Crespi, F. C. L.; Cullen, D. M.; de Angelis, G.; Désesquelles, P.; Dosme, N.; Duchêne, G.; Eberth, J.; Farnea, E.; Filmer, F.; Görgen, A.; Gottardo, A.; Grębosz, J.; Gulmini, M.; Hess, H.; Hughes, T. A.; Jaworski, G.; Jolie, J.; Joshi, P.; Judson, D. S.; Jungclaus, A.; Karkour, N.; Karolak, M.; Kempley, R. S.; Khaplanov, A.; Korten, W.; Ljungvall, J.; Lunardi, S.; Maj, A.; Maron, G.; Męczyński, W.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Molini, P.; Napoli, D. R.; Nolan, P. J.; Norman, M.; Obertelli, A.; Podolyak, Zs.; Pullia, A.; Quintana, B.; Redon, N.; Regan, P. H.; Reiter, P.; Robinson, A. P.; Şahin, E.; Simpson, J.; Salsac, M. D.; Smith, J. F.; Stézowski, O.; Theisen, Ch.; Tonev, D.; Unsworth, C.; Ur, C. A.; Valiente-Dobón, J. J.; Wiens, A.

    2012-11-01

    High-spin states of 40K have been populated in the fusion-evaporation reaction 12C(30Si,np)40K and studied by means of γ-ray spectroscopy techniques using one triple-cluster detector of the Advanced Gamma Tracking Array at the Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro. Several states with excitation energy up to 8 MeV and spin up to 10- have been discovered. These states are discussed in terms of J=3 and T=0 neutron-proton hole pairs. Shell-model calculations in a large model space have shown good agreement with the experimental data for most of the energy levels. The evolution of the structure of this nucleus is here studied as a function of excitation energy and angular momentum.

  3. (226)Ra, (232)Th and (40)K contents in soil samples from Garhwal Himalaya, India, and its radiological implications.

    PubMed

    Ramola, R C; Gusain, G S; Badoni, Manjari; Prasad, Yogesh; Prasad, Ganesh; Ramachandran, T V

    2008-09-01

    The exposure of human beings to ionising radiation from natural sources is a continuing and inescapable feature of life on earth. Natural radionuclides are widely distributed in various geological formations and ecosystems such as rocks, soil groundwater and foodstuffs. In the present study, the distribution of (226)Ra, (232)Th and (40)K was measured in soil samples collected from different lithological units of the Thauldhar and Budhakedar regions of Garhwal Himalaya, India. The collected soil samples were analysed using gamma ray spectrometry. The activity concentrations of the naturally occurring radionuclides (226)Ra, (232)Th and (40)K in these soil samples were found to vary from below detection level (BDL) to 131 +/- 18 Bq kg(-1), 9 +/- 6 to 384 +/- 53 Bq kg(-1) and 471 +/- 96 to 1406 +/- 175 Bq kg(-1), respectively. The distribution of radionuclides depends upon the rock formation and chemical properties within the earth. The activity concentrations vary widely depending on the sample origin. The external absorbed gamma dose rates due to (226)Ra, (232)Th and (40)K were found to vary from 49 to 306 nGy h(-1). The average radium equivalent activity from these soil samples was 300 Bq kg(-1). PMID:18714132

  4. Radium-226, 232Th, and 40K distribution in the environment of Kaiga of south west coast of India.

    PubMed

    Karunakara, N; Somashekarappa, H M; Avadhani, D N; Mahesh, H M; Narayana, Y; Siddappa, K

    2001-05-01

    Systematic studies on gamma radiation level and the distribution of natural radionuclides were carried out under a pre-operational survey for the establishment of baseline data on background radiation level and the distribution of radio-nuclides in the environment of Kaiga, in the south west coast of India, where a nuclear power reactor of 235 MWe has just been commissioned. The external gamma absorbed dose rates prevailing in the region were measured using a portable plastic scintillometer. Soil samples from 18 stations were collected from depth intervals of 0-5, 5-10, and 10-25 cm and analyzed for their 226Ra, 232Th, and 40K activity concentrations by gamma spectrometry employing a 90 cc PGT HpGe detector coupled to an EG&G ORTEC 8K multichannel analyzer. The activity of 226Ra was found to vary between 15.5-61.2 Bq kg(-1) with a mean value of 31.3 Bq kg(-1), that of 232Th varies between 11.4-41.9 Bq kg(-1) with a mean value of 27.5 Bq kg(-1) and of 40K between 78.3-254.8 Bq kg(-1) with a mean value of 159.9 Bq kg(-1) in 0-5 cm soil profiles of the region. The contributions of 238U, 232Th, and 40K to the total gamma absorbed dose rate were 39.9%, 40.7%, and 16.0%, respectively. The gamma absorbed dose rate in air estimated using the results of activity concentration of 226Ra, 232Th, and 40K are found to compare well with that of the direct measurement. The results of the study were compared with the literature values reported for other environs of the country as well as the world, and conclusions are drawn. PMID:11316077

  5. {sup 40}K, {sup 115}Cs and {sup 226}Ra Soil and Plant Content in Seminatural Grasslands of Central Argentina

    SciTech Connect

    Ayub, J. Juri; Velasco, R. H.; Rizzotto, M.; Quintana, E.; Aguiar, J.

    2008-08-07

    Activity concentrations of {sup 40}K, {sup 226}Ra and {sup 137}Cs have been analyzed in soil and plant samples, collected in permanent grassland in central Argentina. Two near areas (A1 and A2) under field conditions with soil undisturbed at least in the last four decades were selected. For each of the three studied radionuclides we do not find differences in the inventories between both areas. The inventories range from 143 kBq m{sup -2} to 197 kBq m{sup -2} for {sup 40}K and from 13 kBq m{sup -2} to 18 kBq m{sup -2} for {sup 226}Ra. The vertical distributions of {sup 40}K and {sup 226}Ra are uniform through de soil profile. For {sup 137}Cs the inventories range from 0.33 kBq m{sup -2} to 0.73 kBq m{sup -2}. In spite of {sup 137}Cs inventories are similar in both areas the distribution through vertical profile is different. {sup 137}Cs activity concentration has a maximum for layers 5-10 cm depth in A1 and 10-15 cm depth in A2. For deeper layers both areas show similar activity concentrations. The diffusion coefficient (D{sub s}) and convection velocity (v{sub s}) are estimated with a convection-diffusion model. D{sub s} values are in the range reported in the bibliography, while v{sub s} values are one order of magnitude higher. After 40 years most {sup 137}Cs fallout is still in the layer 10-15 cm depth. The great penetration of {sup 137}Cs (25 cm) in these soils may be the result of a high sand and low fine materials content. {sup 137}Cs and {sup 226}Ra were not detected in grass samples. Activity concentration of {sup 40}K in vegetal samples ranges from 116 Bq kg{sup -1} to 613 Bq kg{sup -1}. The TF values obtained for {sup 40}K show a lognormal distribution and ranges from 0.05 to 0.42.

  6. Activity Concentrations and Dose Assessment of Gamma Emitting Radionuclides in Canned Tuna and Sardines Produced after the Fukushima Nuclear Accident.

    PubMed

    Ababneh, Zaid Q; Al-Masoud, Fahad I; Ababneh, Anas M

    2016-01-01

    The aim of the present work was to investigate the radioactivity concentrations of gamma emitting radionuclides in canned tuna and sardines that were produced after the Fukushima nuclear accident and to assess the resulting radiation doses to the public. Fifty-eight brands of canned tuna and sardines consumed in the Middle East and produced from different parts of the world were analyzed using a germanium detector. Cesium-137 (137Cs) was not detected above the minimum detectable activity in any of the samples. Natural radionuclides 40K, 226Ra and 228Ra were detected with wide activity concentration ranges and with average values of (in Bq kg(-1) wet weight): 68 ± 36, 0.31 ± 0.45, 0.34 ± 0.25, respectively, in tuna samples and with averages of 129 ± 67, 0.20 ± 0.33, 0.60 ± 0.31 in sardine samples. The results of the activity concentrations of 40K and 226Ra showed some regional dependence. Tuna samples produced in Europe have almost twice the concentration of 40K and half the concentration of 226Ra as compared to samples produced in either East or South Asia and North America. Moreover, sardine samples produced in North Africa and Europe have almost twice the concentrations of 40K and 226Ra as those produced in East or South Asia and North America. Dose assessment due to ingestion of canned seafood was also performed, and the committed effective dose was found to be well within the worldwide average. PMID:26606067

  7. Natural radioactivity (226Ra, 232Th and 40K) and assessment of radiological hazards in the Kestanbol granitoid, Turkey.

    PubMed

    Canbaz, Buket; Cam, N Füsun; Yaprak, Günseli; Candan, Osman

    2010-09-01

    The surveys of natural gamma-emitting radionuclides in rocks and soils from the Ezine plutonic area were conducted during 2007. Direct dose measurement using a survey meter was carried out simultaneously. The present study, which is part of the survey, analysed the activity concentrations of (238)U, (232)Th and (40)K in granitoid samples from all over the region by HPGe gamma spectrometry. The activity concentrations of (226)Ra ranged from 94 to 637 Bq kg(-1), those of (232)Th ranged from 120 to 601 Bq kg(-1)and those of (40)K ranged from 1074 to 1527 Bq kg(-1) in the analysed rock samples from different parts of the pluton. To evaluate the radiological hazard of the natural radioactivity in the samples, the absorbed dose rate (D), the annual effective dose rate, the radium equivalent activity (Ra(eq)) and the external (H(ex)) hazard index were calculated according to the UNSCEAR 2000 report. The thorium-to-uranium concentration ratios were also estimated. PMID:20529959

  8. Body Potassium Content and Radiation Dose from 40K for the Urals Population (Russia)

    PubMed Central

    Tolstykh, Evgenia I.; Degteva, Marina O.; Bougrov, Nikolay G.; Napier, Bruce A.

    2016-01-01

    Long-term whole-body monitoring of radionuclides in residents of the Urals Region has been performed at the Urals Research Center for Radiation Medicine (URCRM, Chelyabinsk). Quantification of 40K was achieved by measuring the 40K photopeak with four phoswich detectors in whole body counter SICH-9.1M. The current study presents the results of 40K measurements in 3,651 women and 1,961 t-test; U-test men aged 11–90; measurements were performed in 2006–2014. The residents belonged to two ethnic groups, Turkic (Tatar, Bashkir) and Slavs (mainly Russian). The levels of 40K-body contents depend upon gender, age, and body mass. Significant ethnic-differences were not found in 40K-body contents and 40K concentrations in terms of Bq per kg of body weight (in groups homogenous by age and gender). Both 40K-body contents and concentrations were significantly higher in men than in women in all age-groups; the difference was about 25%. The measured 40K-body content in men of 20–50 years was about 4200 Bq (134 g of K) and about 3000 Bq (95 g of K) in women. By the age of 80 these values decreased to 3200 Bq (102 g of K) in men and 2500 Bq (80 g of K) in women. Annual dose rates were maximal in the age group of 20–30 years– 0.16 mGy/y for men and 0.13 mGy/y for women. Further, the dose-rates decreased with age and in the groups of 60–80 years were 0.13 mGy/y for men and 0.10 mGy/y for women. Within groups homogeneous by age and gender, individual dose rates are described by a normal statistical distribution. The coefficient of variation ranges from 9 to 14%, and on the average is 12.5%. Doses from naturally occurring 40K accumulated over 70 years were found to be 9.9 mGy for men and 8.3 mGy for women; over 90 years - 12.5 and 10.4 mGy. PMID:27111330

  9. Body Potassium Content and Radiation Dose from 40K for the Urals Population (Russia).

    PubMed

    Tolstykh, Evgenia I; Degteva, Marina O; Bougrov, Nikolay G; Napier, Bruce A

    2016-01-01

    Long-term whole-body monitoring of radionuclides in residents of the Urals Region has been performed at the Urals Research Center for Radiation Medicine (URCRM, Chelyabinsk). Quantification of 40K was achieved by measuring the 40K photopeak with four phoswich detectors in whole body counter SICH-9.1M. The current study presents the results of 40K measurements in 3,651 women and 1,961 t-test; U-test men aged 11-90; measurements were performed in 2006-2014. The residents belonged to two ethnic groups, Turkic (Tatar, Bashkir) and Slavs (mainly Russian). The levels of 40K-body contents depend upon gender, age, and body mass. Significant ethnic-differences were not found in 40K-body contents and 40K concentrations in terms of Bq per kg of body weight (in groups homogenous by age and gender). Both 40K-body contents and concentrations were significantly higher in men than in women in all age-groups; the difference was about 25%. The measured 40K-body content in men of 20-50 years was about 4200 Bq (134 g of K) and about 3000 Bq (95 g of K) in women. By the age of 80 these values decreased to 3200 Bq (102 g of K) in men and 2500 Bq (80 g of K) in women. Annual dose rates were maximal in the age group of 20-30 years- 0.16 mGy/y for men and 0.13 mGy/y for women. Further, the dose-rates decreased with age and in the groups of 60-80 years were 0.13 mGy/y for men and 0.10 mGy/y for women. Within groups homogeneous by age and gender, individual dose rates are described by a normal statistical distribution. The coefficient of variation ranges from 9 to 14%, and on the average is 12.5%. Doses from naturally occurring 40K accumulated over 70 years were found to be 9.9 mGy for men and 8.3 mGy for women; over 90 years - 12.5 and 10.4 mGy. PMID:27111330

  10. Primordial radioactivity ((238)U, (232)Th and (40)K) measurements for soils of Ludhiana district of Punjab, India.

    PubMed

    Badhan, K; Mehra, R

    2012-11-01

    The aim of the present work was to study the activity concentration and absorbed gamma dose rates due to primordial radionuclides ((238)U, (232)Th and (40)K) for the soil of different villages of Ludhiana district of Punjab, India using a high-purity germanium detector based on high resolution gamma-ray spectrometry. The average activity concentrations of (238)U, (232)Th and (40)K in the soil samples have been found to be 28.58, 50.95 and 569.59 Bq kg(-1), respectively, which gives the total gamma dose rate contribution of 68.50 nGy h(-1). To evaluate the radiological hazard of the natural radioactivity, the radium equivalent activity, the external hazard index, the absorbed dose rate and the effective dose rate have been calculated. The calculated radium equivalent activity values are on the lower side of the recommended safe limit value of 370 Bq kg(-1) by Organization of Economic and Control Department. The calculated value of external health hazard index is lower than unity. PMID:22899219

  11. 40 kW Stirling engine for solid fuel

    SciTech Connect

    Carlsen, H.; Ammundsen, N.; Traerup, J.

    1996-12-31

    The external combustion in a Stirling engine makes it very attractive for utilization of solid fuels in decentralized combined heat and power (CHP) plants. Only few projects have concentrated on the development of Stirling engines specifically for biomass. In this project a Stirling engine has been designed primarily for utilization of wood chips. Maximum shaft power is 40 kW corresponding to an electric output of 36 kW. Biomass needs more space in the combustion chamber compared to gas and liquid fuels, and a large heat transfer area is necessary. The design of the new Stirling engine has been adapted to the special demands of combustion of wood chips, resulting in a large engine compared to engines for gas or liquid fuels. The engine has four-cylinders arranged in a square. The design is made as a hermetic unit, where the alternator is built into the pressurized crankcase so that dynamic seals are avoided. Grease lubricated bearings are used in a special designed crank mechanism, which eliminates guiding forces on the pistons Helium is used as working gas at 4 MPa mean pressure. The first test of the 40 kW engine with natural gas as fuel has been made in the laboratory, and the results are in agreement with predicted results from simulation programs. The wood chips combustion system has been tested for some time with very promising results. When the laboratory test of the engine is finished, the test of the complete system will be initiated. The paper describes the engine and results from the test program. Expectations to maintenance and operation problems are also discussed.

  12. Measurement of (238)U, (228)Ra, (226)Ra, (40)K and (137)Cs in foodstuffs samples collected from coastal areas of China.

    PubMed

    Tuo, Fei; Zhang, Qing; Zhou, Qiang; Xu, Cuihua; Zhang, Jing; Li, Wenhong; Zhang, Jianfeng; Su, Xu

    2016-05-01

    This study represents a total of 245 samples collected. The activities of (238)U, (228)Ra, (226)Ra, (40)K and (137)Cs were determined in samples of vegetables, tea, cereal (rice, wheat and corn), meat, poultry, freshwater product, seafood and seaweed that collected from the 30km safety zone of the Nuclear Power Plants (NPPs) area. All the samples radionuclide activities were quantified by using High Purity Germanium (HPGe) gamma spectrometry. The geometric mean concentrations (Bqkg(-1) wet weight) for (238)U, (228)Ra, (226)Ra, (40)K, and (137)Cs in all investigated foodstuffs samples, are 0.13, 0.16, 0.11, 68 and 0.02, respectively. The arithmetic mean concentrations (Bqkg(-1) wet weight) for (238)U, (228)Ra, (226)Ra, (40)K, and (137)Cs in all investigated foodstuffs samples, are 0.34, 0.65, 0.32, 111 and 0.09, respectively. Results of this study were compared with others, the measured values are the same with those of a previous investigation. Radiation doses due to the consumption of these foodstuffs to humans are estimated to comprise around 37-46% of the annual dose limit for public. PMID:26926376

  13. Distribution and possible dietary intake of radioactive 137Cs, 40K and 226Ra with the pantropical mushroom Macrocybe gigantea in SW China.

    PubMed

    Falandysz, Jerzy; Zhang, Ji; Zalewska, Tamara; Apanel, Anna; Wang, Yuanzhong; Wiejak, Anna

    2015-01-01

    There is scarcity of data on contamination with radiocesium 134/137Cs of edible mushrooms from the Southwestern Asia. This study aimed to get insight into activity concentration of artificial nuclides 134/137Cs and natural 40K and 226Ra in mushrooms from Yunnan province, which is major producer in China. The specimens of pantropical mushroom Macrocybe gigantea were collected from the wild and from a farm across Yunnan land in 2012-2013 and analyzed using gamma spectrometry with hyperpure germanium coaxial detector (HPGe). M. gigantea showed low activity concentrations of 137Cs (median value for dehydrated caps was 4.5 Bq kg(-1) and 5.4 Bq kg(-1) for stipes) while 134Cs was not detected. Natural radionuclide 40K showed 2-3 orders of magnitude greater activity concentration compared to artificial 137Cs in M. gigantea. The activity concentrations of 226Ra from uranium and radium decay series for most of the consignments of M. gigantea examined were below the method's limit of detection. The nominal effective dose equivalent for the Yunnan people from the dietary intake of 137Cs was assessed to be below 0.01 μSv per annum on the average, and that from 40K to be below 0.1 μSv per annum. Data available for the first time on activity concentrations of 137Cs in wild-grown saprobic mushroom from this region of Asia suggest low pollution with radiocesium from fallout there. Hence, the likely health risks from intake of 137Cs from cooked M. gigantea are in practice of mushrooms absent for human consumers there. Because of abundance of mushrooms in Yunnan and high significance of the region as producer and exporter a wider study using many species is necessary to fill a gap on possible radioactive contamination and risk to mushroom consumers. PMID:26061207

  14. Natural and artificial radionuclide activity concentrations in surface sediments of Izmit Bay, Turkey.

    PubMed

    Ergül, Halim Aytekin; Belivermiş, Murat; Kılıç, Önder; Topcuoğlu, Sayhan; Çotuk, Yavuz

    2013-12-01

    Surface sediments from the north-eastern coast of the Marmara Sea, Turkey's most industrialized coastal region, were enriched with radioisotopes from the Chernobyl explosion in 1986. Caesium-137 in these sediments is also thought to originate from one former paper mill located nearby that used wood contaminated by Chernobyl explosion-originated (137)Cs for paper production. The average activity concentration of the (137)Cs was 21 Bq kg(-1), while naturally occurring radioisotopes, i.e. (40)K, (226)Ra, and (228)Ra, were 568, 18 and 24 Bq kg(-1), respectively, in surface sediments. The natural radionuclide activities reached their highest levels near petrochemical, phosphate and fertilizer processing facilities. Average (137)Cs activities were generally up to ten times higher than in Middle Eastern marine sediments and lower than those in Northern European sediments. PMID:23981563

  15. Joint determination of 40K decay constants and 40Ar∗/ 40K for the Fish Canyon sanidine standard, and improved accuracy for 40Ar/ 39Ar geochronology

    NASA Astrophysics Data System (ADS)

    Renne, Paul R.; Mundil, Roland; Balco, Greg; Min, Kyoungwon; Ludwig, Kenneth R.

    2010-09-01

    40Ar/ 39Ar and K-Ar geochronology have long suffered from large systematic errors arising from imprecise K and Ar isotopic data for standards and imprecisely determined decay constants for the branched decay of 40K by electron capture and β - emission. This study presents a statistical optimization approach allowing constraints from 40K activity data, K-Ar isotopic data, and pairs of 238U- 206Pb and 40Ar/ 39Ar data for rigorously selected rocks to be used as inputs for estimating the partial decay constants ( λ ɛ and λ β) of 40K and the 40Ar∗/ 40K ratio ( κFCs) of the widely used Fish Canyon sanidine (FCs) standard. This yields values of κFCs = (1.6418 ± 0.0045) × 10 -3, λ ɛ = (0.5755 ± 0.0016) × 10 -10 a -1 and λ β = (4.9737 ± 0.0093) × 10 -10 a -1. These results improve uncertainties in the decay constants by a factor of >4 relative to values derived from activity data alone. Uncertainties in these variables determined by our approach are moderately to highly correlated (cov( κFCs, λ ɛ) = 7.1889 × 10 -19, cov( κFCs, λ β) = -7.1390 × 10 -19, cov( λ ɛ, λ β) = -3.4497 × 10 -26) and one must take account of the covariances in error propagation by either linear or Monte Carlo methods. 40Ar/ 39Ar age errors estimated from these results are significantly reduced relative to previous calibrations. Also, age errors are smaller for a comparable level of isotopic measurement precision than those produced by the 238U/ 206Pb system, because the 40Ar/ 39Ar system is now jointly calibrated by both the 40K and 238U decay constants, and because λ ɛ( 40K) < λ( 238U). Based on this new calibration, the age of the widely used Fish Canyon sanidine standard is 28.305 ± 0.036 Ma. The increased accuracy of 40Ar/ 39Ar ages is now adequate to provide meaningful validation of high-precision U/Pb or astronomical tuning ages in cases where closed system behavior of K and Ar can be established.

  16. High precision determination of the terrestrial 40K abundance

    NASA Astrophysics Data System (ADS)

    Naumenko, Maria O.; Mezger, Klaus; Nägler, Thomas F.; Villa, Igor M.

    2013-12-01

    Recent improvements in the precision of mass spectrometric measurements have reduced the uncertainty of K-Ar and 39Ar-40Ar ages measured on geological materials. Now the major sources of uncertainty are the uncertainties on the 40K decay constant and the absolute abundance of 40K. In order to improve on this situation we determined the abundance of the 40K isotope in terrestrial standards. A ThermoFischer Triton+ thermal ionization mass spectrometer was used for K isotope ratio measurements of the NIST K standard reference materials SRM 918b and SRM 985. Ion beams were measured in Faraday cups with amplifiers equipped with 1010, 1011 and 1012 Ω resistors. Three measurement protocols were used: (A) dynamic measurement with in-run fractionation correction by normalization to the IUPAC recommended isotope ratio 41K/39K = 0.072 1677; (B) total evaporation; (C) a modified total evaporation with interblock baseline measurements. Different measurement protocols were combined with different loading procedures. The best results were obtained by loading samples on single oxidized tantalum filaments with 0.1 M H3PO4. The total ion yields (ionization + transmission) were tested for the evaporation procedures (B) and (C) and ranged up to 48%. The resulting best estimate for the 40K/39K ratio is 0.000 125 116 ± 57 (2σ), corresponding to an isotopic abundance 40K/K = (1.1668 ± 8) × 10-4.

  17. Leaves of higher plants as biomonitors of radionuclides (137Cs, 40K, 210Pb and 7Be) in urban air.

    PubMed

    Todorović, Dragana; Popović, Dragana; Ajtić, Jelena; Nikolić, Jelena

    2013-01-01

    Leaves of linden (Tilia tomentosa L. and Tilia cordata Mill.) and horse chestnut (Aesculus hippocastanum L.) were analysed as biomonitors of radionuclides in urban air. Samples of soils, leaves and aerosols were collected in Belgrade, Serbia. Activities of (137)Cs, (40)K, (210)Pb and (7)Be in the samples were measured on an HPGe detector by standard gamma spectrometry. "Soil-to-leaves" transfer factors were calculated. Student's t test and linear Pearson correlation coefficients were used for statistical analysis. Differences in local conditions at the sampling sites were not significant, and the mechanisms of the radionuclides' accumulation in both plant species are similar. Ceasium-137 was detected in some of the leaf samples only. Transfer factors for (137)Cs and (40)K were (0.03-0.08) and 1.3, respectively. The concentrations of (210)Pb and (7)Be in leaves were higher in autumn than in spring, and there were some similarities in their seasonal patterns in leaves and in air. Weak to medium correlation was obtained for the (210)Pb and (7)Be activities in leaves and aerosols. Large positive correlation was obtained for the (210)Pb activities in linden leaves and the mean activity in aerosols for the preceding months. Different primary modes of radionuclides accumulation in leaves were observed. Since large positive correlation was obtained for the (210)Pb activity in linden leaves and the mean in aerosols for the preceding months, mature linden leaves could be used as biomonitors of recent (210)Pb activity in air. PMID:22562351

  18. Vertical distributions of 137Cs, 40K, 232Th and 226Ra in soil samples from Istanbul and its environs, Turkey.

    PubMed

    Belivermiş, Murat

    2012-09-01

    Determining the distribution of natural and artificial radionuclides in soil profiles as well as the surface layer of the soil is necessary due to the fact that radionuclides can enter the food chain from deeper soil layers and also contaminate ground water. In the current study, the activity-depth profiles of (137)Cs were determined in soil samples from 20 sites in and around the city of Istanbul. Naturally  occurring radionuclides were determined at 12 of the locations. Uncultivated soil samples were taken in six horizontal layers at each location. Activity concentrations were measured with a gamma spectrometer. The impacts of texture, organic matter and pH of the soil on the vertical distribution of the radionuclides were also studied. The average and standard deviations of (137)Cs and (40)K activity concentrations in soil at a depth of 5 cm were found to be 16.46±14.71 and 450.2±239.1 Bq kg(-1), respectively. The activity concentrations of (40)K, (232)Th and (226)Ra were distributed uniformly with regard to soil depth. The depth distribution of (137)Cs generally fitted a linear function. The study revealed that >20 y after the Chernobyl disaster of 1986, 55 % of (137)Cs still remains in the upper 10 cm of soil in the Istanbul environment. PMID:22408185

  19. X-34 40K Fastrac II Engine Test

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This is a photo of an X-34 40K Fastrac II duration test performed at the Marshall Space Flight Center test stand 116 (TS116) in June 1997. Engine ignition is started with Tea-Gas which makes the start burn green. The X-34 program was cancelled in 2001.

  20. Determination of potassium in several plants and study of potassium transfer to different beverages, including tequila, by measurement of 40K

    NASA Astrophysics Data System (ADS)

    Navarrete, J. M.; Muller, G.; Cabrera, L.; Martinez, T.

    2006-01-01

    Measurement of 40K was used for determination of potassium concentrations in leaves of agave and maguey cactus leaves, and coffee beans of various origins. The procedure was also used to study potassium transfer to tequila (alcoholic drink made of agave cactus), and the cactus and coffee infusions using 40K as a natural radioactive tracer. Counting of 40K in Marinelli containers with the aid of a low background NaI(Ti) scintillation detection system for 12 24 hours was employed. The method appeared to be simple and suitable for determination of potassium concentrations in large samples, which eliminates homogeneity problems.

  1. High Precision 40K/39K Ratio Determination

    NASA Astrophysics Data System (ADS)

    Naumenko, M. O.; Mezger, K.; Nagler, T. F.; Villa, I. M.

    2012-12-01

    Potassium is one of the eight most abundant chemical elements in the Earth's crust and a major element in many rock-forming minerals. The isotope 40K is radioactive and undergoes β- decay to 40Ca (ca. 89.3%) and electron capture to 40Ar (ca. 10.7%). Both decays can potentially be used as dating systems. The most commonly used branch is the decay of 40K to 40Ar because it can yield highly precise ages. Both decay schemes rely on the knowledge of the 40K branching ratio and the natural 40K abundance. A 40K abundance of 0.011672±41 % was measured on terrestrial material [1]. The relative uncertainty of 0.35 % has not been improved since. Recent improvements in the precision of mass spectrometric measurements have led to the situation that the uncertainties on the K decay constant and the abundance of 40K are a major source of uncertainty on the measured ages. A more precise definition of the 40K decay constant was attempted by different research groups within the last decade [2-9] but the goal of obtaining 0.1 % relative uncertainty on K-Ar ages for geological materials, as requested by the EARTHtime initiative, has not been achieved yet. In order to improve on this situation we studied the abundances of the K isotopes in terrestrial standards. A ThermoFischer Triton+ thermal ionisation mass spectrometer was used for K isotope ratio measurements of the NIST SRM 918b K standard loaded on Ta filaments with 0.1M phosphoric acid. Three techniques were applied: (A) dynamic measurement with in-run normalisation to the IUPAC value 41K/39K=0.072168; (B) a simple total evaporation procedure; (C) the "NBL-modified" total evaporation [10]. The 40K ion beam was measured in a Faraday cup with a 1E12 Ω resistor; 39K and 41K were collected in Faraday cups with 1E11 Ω resistors. Amplifier gains were intercalibrated by supplying fixed voltages off-line. Different measurement techniques were combined with different loading procedures. We also tested ionisation yields for the

  2. Photovoltaic concentrator assembly with optically active cover

    DOEpatents

    Plesniak, Adam P

    2014-01-21

    A photovoltaic concentrator assembly that includes a housing that defines an internal volume and includes a rim, wherein the rim defines an opening into the internal volume, a photovoltaic cell positioned in the internal volume, and an optical element that includes an optically active body and a flange extending outward from the body, wherein the flange is sealingly engaged with the rim of the housing to enclose the internal volume.

  3. Diffusion in the Muscovite 40K Decay System (Invited)

    NASA Astrophysics Data System (ADS)

    Harrison, T. M.

    2010-12-01

    The considerable potential of muscovite for thermochronological applications is beginning to be fully exploited following the belated publication of Ar kinetic data. Muscovite’s high potassium content, low solubility for excess 40Ar*, and ubiquitous presence in regionally metamorphosed terranes make it an important phase for 40Ar/39Ar thermochronometry, particularly in light of recognition that both age spectra and vacuum-step-heating-derived 39Ar Arrhenius plots reflect Ar release via the same volume diffusion mechanism. Thus instead of assuming a nominal closure temperature to estimate a single T-t datum, continuous and accurate thermal histories can be inferred in a similar fashion to that well-documented for K-feldspar using the multi-diffusion domain (MDD) model. The Arrhenius parameters for Ar diffusion in muscovite (E=64 kcal/mol, Do=4 cm2/s) correspond to an effective intragrain closure temperature range of ~500 to 300oC for ca. 100 μm grains cooling at ~10oC/Ma at 5 kbar. However, even greater exploitation of the 40K decay system remains possible as only one of every ten 40K atoms decay to 40Ar. The other 90% decay to 40Ca giving the 40K-40Ca branch, in principle, greater sensitivity for dating high K/Ca minerals such as muscovite. The advent of the ‘double-plus’ SIMS 40K++-40Ca++ dating method, which permits analysis of Ca isotopes at an MRP of ~4k rather than the ~25k required for full separation of 40K+ from 40Ca+, opens up the prospect of directly revealing 40K-40Ca closure profiles in muscovite (as opposed to their indirect inference from inversion of 40Ar/39Ar data through the MDD model) at a gain of enhanced precision and accuracy in thermal history reconstruction. We have used SIMS to observe K-Ca age variations in natural muscovites pressed into In. Translating this data into thermal history information, however, requires knowledge of the Arrhenius parameters for Ca tracer diffusion in muscovite. We are undertaking hydrothermal piston

  4. Commercial Modular Aero-Propulsion System Simulation 40k

    NASA Technical Reports Server (NTRS)

    Guo, Ten-Huei; Lavelle, Thomas; Litt, Jonathan; Csank, Jeffrey; May, Ryan

    2011-01-01

    The Commercial Modular Aero-Propulsion System Simulation 40k (CMAPSS40k) software package is a nonlinear dynamic simulation of a 40,000-pound (approximately equals 178-kN) thrust class commercial turbofan engine, written in the MATLAB/Simulink environment. The model has been tuned to capture the behavior of flight test data, and is capable of running at any point in the flight envelope [up to 40,000 ft (approximately equals 12,200 m) and Mach 0.8]. In addition to the open-loop engine, the simulation includes a controller whose architecture is representative of that found in industry. C-MAPSS40k fills the need for an easy-to-use, realistic, transient simulation of a medium-size commercial turbofan engine with a representative controller. It is a detailed component level model (CLM) written in the industry-standard graphical MATLAB/Simulink environment to allow for easy modification and portability. At the time of this reporting, no other such model exists in the public domain.

  5. Concentration and temperature effects on ovostatin activity

    NASA Technical Reports Server (NTRS)

    Moriarity, Debra M.

    1994-01-01

    Light scattering experiments performed at Mississippi State University using MSFC ovostatin preparations indicated that at low ovostatin concentrations, below 0.2 mg/ml, the protein was dissociating from a tetramer into dimers. Since the proposed mechanism of action involved the tetrameric form of the protein, we hypothesized that perhaps under the conditions of our assays at various O/T ratios the ovostatin was becoming dissociated into an inactive dimer. To examine this possibility we assayed the ovostatin activity as a function of ovostatin concentration and of temperature of the assay. Data are presented that show the results of these assays at 23 C, 30 C, 37 C and 42 C respectively. The data are highly suggestive that there is a decrease in ovostatin activity as the concentration of the protein falls below 0.06 mg/ml. This may not be of any physiological importance, however, since the concentration of ovostatin in the egg is about 0.5 mg/ml. Curiously, the dissociation of the tetramer into dimers does not show a significant temperature dependence as would be expected for an equilibrium reaction. Whether this is in fact the case, or whether the differences are so small as to not be discerned from the current data remains to be seen. Another aspect to consider is that in the egg the primary role of the ovostatin may or may not be as a protease inhibitor. Although the inhibition of collagenase by ovostatin may be an important aspect of embryogenesis, it is also possible that it functions as a binding protein for some substance. In this regard, all ovostatin preparations from MSFC have shown an approximately 88,000 MW protein associated with the ovostatin. The identity of this protein is not currently known and may be the subject of future studies.

  6. Soil to rice transfer factors for (226)Ra, (228)Ra, (210)Pb, (40)K and (137)Cs: a study on rice grown in India.

    PubMed

    Karunakara, N; Rao, Chetan; Ujwal, P; Yashodhara, I; Kumara, Sudeep; Ravi, P M

    2013-04-01

    India is the second largest producer of rice (Oryza sativa L.) in the world and rice is an essential component of the diet for a majority of the population in India. However, detailed studies aimed at the evaluation of radionuclide transfer factors (F(v)) for the rice grown in India are almost non-existent. This paper presents the soil to rice transfer factors for natural ((226)Ra, (228)Ra, (40)K, and (210)Pb) and artificial ((137)Cs) radionuclides for rice grown in natural field conditions on the West Coast of India. A rice field was developed very close to the Kaiga nuclear power plant and the water required for this field was drawn from the cooling water discharge canal of the power plant. For a comparative study of the radionuclide transfer factors, rice samples were also collected from the rice fields of nearby villages. The study showed that the (226)Ra and (228)Ra activity concentrations were below detection levels in different organs of the rice plant. The soil to un-hulled rice grain (40)K transfer factor varied in the range of 6.5 × 10(-1) to 2.9 with a mean of 0.15 × 10(1), and of (210)Pb varied in the range of <1.2 × 10(-2) to 8.1 × 10(-1) with a mean of 1.4 × 10(-1), and of (137)Cs varied in the range of 6.6 × 10(-2) to 3.4 × 10(-1) with a mean of 2.1 × 10(-1). The mean values of un-hulled grain to white rice processing retention factors (F(r)) were 0.12 for (40)K, 0.03 for (210)Pb, and 0.14 for (137)Cs. Using these processing retention factors, the soil to white rice transfer factors were estimated and these were found to have mean values of 1.8 × 10(-1), 4.2 × 10(-3), and 3.0 × 10(-2) for (40)K, (210)Pb, and (137)Cs, respectively. The study has shown that the transfer of (40)K was higher for above the ground organs than for the root, but (210)Pb and (137)Cs were retained in the root and their transfer to above the ground organs of the rice plant is significantly lower. PMID:23266913

  7. Activity concentration of natural radioactive nuclides in nonmetallic industrial raw materials in Japan.

    PubMed

    Iwaoka, Kazuki; Tabe, Hiroyuki; Yonehara, Hidenori

    2014-11-01

    Natural materials such as rock, ore, and clay, containing natural radioactive nuclides are widely used as industrial raw materials in Japan. If these are high concentrations, the workers who handle the material can be unknowingly exposed to radiation at a high level. In this study, about 80 nonmetallic natural materials frequently used as industrial raw materials in Japan were comprehensively collected from several industrial companies, and the activity concentrations of (238)U series, (232)Th series and (40)K in the materials was determined by ICP-MS (inductively-coupled plasma mass spectrometer) and gamma ray spectrum analyses. Effective doses to workers handling them were estimated by using methods for dose estimation given in the RP 122. We found the activity concentrations to be lower than the critical values defined by regulatory requirements as described in the IAEA Safety Guide. The maximum estimated effective dose to workers handling these materials was 0.16 mSv y(-1), which was lower than the reference level (1-20 mSv y(-1)) for existing situation given in the ICRP Publ.103. PMID:25046866

  8. In situ 40K-40Ca ‘double-plus’ SIMS dating resolves Klokken feldspar 40K-40Ar paradox

    NASA Astrophysics Data System (ADS)

    Harrison, T. Mark; Heizler, Matthew T.; McKeegan, Kevin D.; Schmitt, Axel K.

    2010-11-01

    The 40K- 40Ca decay system has not been widely utilized as a geochronometer because quantification of radiogenic daughter is difficult except in old, extremely high K/Ca domains. Even these environments have not heretofore been exploited by ion microprobe analysis due to the very high mass resolving power (MRP) of 25,000 required to separate 40K + from 40Ca +. We introduce a method that utilizes doubly-charged K and Ca species which permits isotopic measurements to be made at relatively low MRP (~ 5000). We used this K-Ca 'double-plus' approach to address an enduring controversy in 40Ar/ 39Ar thermochronology revolving around exsolved alkali feldspars from the 1166 Ma Klokken syenite (southern Greenland). Ion microprobe 40K- 40Ca analysis of Klokken samples reveal both isochron and pseudoisochron behaviors that reflect episodic isotopic and chemical exchange of coarsely exsolved perthites and a near end-member K-feldspar until ≤ 719 Ma, and perhaps as late at ~ 400 Ma. Feldspar microtextures in the Klokken syenite evolved over a protracted interval by non-thermal processes (fluid-assisted recrystallization) and thus this sample makes a poor model from which to address the general validity of 40Ar/ 39Ar thermochronological methodologies.

  9. Estimation of dose contribution from 226Ra, 232Th and 40K radon exhalation rates in soil samples from Shivalik foot hills in India.

    PubMed

    Chauhan, R P; Chauhan, Pooja; Pundir, Anil; Kamboj, Sunil; Bansal, Vakul; Saini, R S

    2014-01-01

    The concentration of radium, thorium and potassium and radon exhalation rates in soil samples collected from Shivalik foot hills in the states of Haryana and Himachal Pradesh (India) were experimentally measured. A high-resolution gamma-ray spectroscopic system was used for the measurement of natural radioactivity ((226)Ra, (232)Th and (40)K) at Inter-University Accelerator Center, New Delhi, using a coaxial n-type high-purity germanium detector (EG&G, ORTEC, Oak Ridge, USA). The mass exhalation rates (EM) of radon in soil samples from the study area measured by 'sealed canister technique' using LR-115 type II track detectors varied from 50±1 to 143±6 mBqkg(-1) h(-1). The activity concentrations of (226)Ra, (232)Th and (40)K in various soil samples of the study area varied from 31±1.3 to 63±4.6, 53±1.8 to 78±2.6 and 472±4.8 to 630±7.0 Bq kg(-1) respectively. The results indicated some higher levels of radioactivity in Lal Dhang peak area of the hills compared with other locations under study. PMID:23893776

  10. Micelles Protect and Concentrate Activated Acetic Acid

    NASA Astrophysics Data System (ADS)

    Todd, Zoe; House, C.

    2014-01-01

    As more and more exoplanets are discovered and the habitability of such planets is considered, one can turn to searching for the origin of life on Earth in order to better understand what makes a habitable planet. Activated acetic acid, or methyl thioacetate, has been proposed to be central to the origin of life on Earth, and also as an important energy currency molecule in early cellular evolution. We have investigated the hydrolysis of methyl thioacetate under various conditions. Its uncatalyzed rate of hydrolysis is about three orders of magnitude faster (K = 0.00663 s^-1; 100°C, pH 7.5, concentration = 0.33mM) than published rates for its catalyzed production making it unlikely to accumulate under prebiotic conditions. However, we also observed that methyl thioacetate was protected from hydrolysis when inside its own hydrophobic droplets. We found that methyl thioacetate protection from hydrolysis was also possible in droplets of hexane and in the membranes of nonanoic acid micelles. Thus, the hydrophobic regions of prebiotic micelles and early cell membranes could have offered a refuge for this energetic molecule increasing its lifetime in close proximity to the reactions for which it would be needed. Methyl thioacetate could thus be important for the origin of life on Earth and perhaps for better understanding the potential habitability of other planets.

  11. A thalium-doped sodium iodide well counter for radioactive tracer applications with naturally-abundant 40K

    NASA Astrophysics Data System (ADS)

    Parker, Andrew J.; Boxall, Colin; Joyce, Malcolm J.; Schotanus, Paul

    2013-09-01

    The use of a thallium-doped sodium-iodide well-type scintillation detector for the assay of the low-activity radioisotope 40K, in open-source potassium chloride aqueous solutions, is described. The hazards, safety concerns and radiowaste generation associated with using open-source radioactive isotopes can present significant difficulties, the use of hot cells and escalated costs in radioanalytical laboratory research. A solution to this is the use of low-hazard alternatives that mimic the migration and dispersion characteristics of notable fission products (in this case 137Cs). The use of NaI(Tl) as a detection medium for naturally-abundant levels of 40K in a range of media is widespread, but the use of 40K as a radioactive tracer has not been reported. The use of such low-activity sources is often complicated by the ability to detect them efficiently. In this paper a scintillator detector designed to detect the naturally-abundant 40K present in potassium chloride in tracer applications is described. Examples of the use of potassium chloride as a tracer are given in the context of ion exchange and electrochemical migration studies, and comparisons in performance are drawn from literature with hyper pure germanium semiconductor detectors, which are more commonly utilised detectors in high-resolution counting applications.

  12. Analysis of Potassium in Bricks--Determining the Dose Rate from {sup 40}K for Thermoluminescence Dating

    SciTech Connect

    Musilek, Ladislav; Polach, Tomas; Trojek, Tomas

    2008-08-07

    Thermoluminescence (TL) dating is based on accumulating the natural radiation dose in the material of a dated artefact (brick, pottery, etc.), and comparing the dose accumulated during the lifetime of the object with the dose rate within the sample collected for TL measurement. Determining the dose rate from natural radionuclides in materials is one of the most important and most difficult parts of the technique. The most important radionuclides present are usually nuclides of the uranium and thorium decay series and {sup 40}K. An analysis of the total potassium concentration enables us to determine the {sup 40}K content effectively, and from this it is possible to calculate the dose rate originating from this radiation source. X-ray fluorescence (XRF) analysis can be used to determine the potassium concentration in bricks rapidly and efficiently. The procedure for analysing potassium, examples of results of dose rate calculation and possible sources of error are described here.

  13. Artificial (137)Cs and (134)Cs and natural (40)K in sclerotia of Wolfiporia extensa fungus collected across of the Yunnan land in China.

    PubMed

    Wang, Yuanzhong; Zalewska, Tamara; Apanel, Anna; Zhang, Ji; Maćkiewicz, Zbigniew; Wiejak, Anna; Falandysz, Jerzy

    2015-01-01

    Dried sclerotia of Wolfiporia extensa has a long history of medicinal and grocery uses in Asia and elsewhere. This study aimed at providing and evaluating data on activity concentrations from artificial (137)Cs and (134)Cs radionuclides and natural (40)K in sclerotia collected across of the Yunnan land in China, which is generally lacking information. Sclerotia of W. extensa showed a low contamination with (137)Cs while (134)Cs was below limit of quantification. Estimated, the nominal value of effective dose (μSv) received by adult eating annually 50 g of the 'average' Yunnan's origin sclerotia contained in the 'Fuling jiabing' snack due to (137)Cs could be between < 0.00091 and 0.0047 ± 0.0007 μSv per capita and at < 0.000015 to 0.000078 ± 0.000012 μSv per kg of body mass, which is a very low exposure. This study has revealed also that sclerotia of W. extensa are characterized by very low content of (40)K (hence also of total K) when compared to fruiting bodies of many saprobic and mycorrhizal mushrooms. PMID:26079339

  14. Radiological hazards of Narghile (hookah, shisha, goza) smoking: activity concentrations and dose assessment.

    PubMed

    Khater, Ashraf E M; Abd El-Aziz, Nawal S; Al-Sewaidan, Hamed A; Chaouachi, Kamal

    2008-12-01

    Narghile (hookah, shisha, goza, "water-pipe") smoking has become fashionable worldwide. Its tobacco pastes, known as moassel and jurak, are not standardized and generally contain about 30-50% (sometimes more) tobacco, molasses/juice of sugarcane, various spices and dried fruits (particularly in jurak) and, in the case of moassel, glycerol and flavoring essences. Tobacco contains minute amounts of radiotoxic elements such as (210)Pb, (210)Po and uranium, which are inhaled via smoking. Only very few data have been published on the concentrations of natural radionuclides in narghile tobacco mixtures. Consequently, the aim of this study was to draw first conclusions on the potential hazards of radioactivity in moassel tobacco in relation to narghile smoking. The results indicate the existence of a wide range in the radioactivity contents where the average (range) activity concentrations of (238)U, (234)Th (226)Ra, (210)Pb, (210)Po, (232)Th and (40)K, in Bq/kg dry weight were 55 (19-93), 11 (3-23), 3 (1.2-8), 14 (3-29), 13 (7-32), 7 (4-10) and 719 (437-1044)Bq/kg dry weight, respectively. The average concentrations of natural radionuclides in moassel tobacco pastes are comparable to their concentration in Greek cigarettes and tobacco leaves, and lower than that of Brazilian tobacco leaves. The distribution pattern of these radionuclides after smoking, between smoke, ash and filter, is unknown, except for (210)Po during cigarette smoking and from one existing study during moassel smoking. Radiological dose assessment due to intake of natural radionuclides was calculated and the possible radio-toxicity of the measured radionuclides is briefly discussed. PMID:18768240

  15. Radionuclide activities and metal concentrations in sediments of the Sebou Estuary, NW Morocco, following a flooding event.

    PubMed

    Laissaoui, A; Mas, J L; Hurtado, S; Ziad, N; Villa, M; Benmansour, M

    2013-06-01

    This study presents metal concentrations (Fe, Mg, Mn, Co, Cu, Zn, Pb, As, Sr and V) and radionuclide activities ((40)K, (137)Cs, (210)Pb, (226)Ra, (228)Ac, (234)Th and (212)Pb) in surface deposits and a sediment core from the Sebou Estuary, Northwest Morocco. Samples were collected in April 2009, about 2 months after a flooding event, and analysed using a well-type coaxial gamma-ray detector and inductively coupled plasma-quadrupole mass spectrometry. Activities of radionuclides and concentrations of almost all elements in surface samples displayed only moderate spatial variation, suggesting homogenous deposition of eroded local soil in response to intense precipitation. Excess (210)Pb displayed relatively constant activity throughout the sediment core, preventing dating and precluding determination of the historical accumulation rates of pollutants at the core site. Some elements showed non-systematic trends with depth and displayed local maxima and minima. Other elements presented relatively systematic concentration trends or relatively constant levels with discrete maxima and/or minima. Except for Mn, Sr and Cr, all metal concentrations in sediment were below levels typical of polluted systems, suggesting little human impact or losses of metals from sediment particles. PMID:23054286

  16. Activation concentrations outside the SSC accelerator enclosures

    SciTech Connect

    Baker, S.; Bull, J.; Stapleton, G.

    1994-10-01

    Activation of groundwater due to beam loss at the Superconducting Super Collider (SSC) is discussed, with activation criteria and models presented. Estimates are given of maximum beam losses allowed in the various accelerators of the SSC to meet federal drinking water standards, assuming no additional shielding is provided.

  17. Sequence and expression of an Eisenia-fetida-derived cDNA clone that encodes the 40-kDa fetidin antibacterial protein.

    PubMed

    Lassegues, M; Milochau, A; Doignon, F; Du Pasquier, L; Valembois, P

    1997-06-15

    Fetidins are 40-kDa and 45-kDa hemolytic and antibacterial glycoproteins present in the coelomic fluid of the earthworm Eisenia fetida andrei. By screening a cDNA library with a polyclonal antifetidin serum, we have cloned a cDNA that encoded the 40-kDa fetidin. The clone contains an insert of 1.44 kb encoding a protein of 34 kDa, which corresponds to the size of deglycosylated fetidins. The recombinant protein inhibits Bacillus megaterium growth. Restriction fragment polymorphisms were observed on Southern blots and correspond to a known protein polymorphism. The sequence of the cDNA contains a peroxidase signature and fetidins from earthworm coelomic fluid have peroxidase activity. The 40-kDa and 45-kDa fetidins therefore represent two related polymorphic defence factors in invertebrates. PMID:9219536

  18. Study on vertical distribution of radionuclides (40K, Th and U) in soil collected from Manjung district

    NASA Astrophysics Data System (ADS)

    Zainal, Fetri; Hamzah, Zaini; Saat, Ahmad; Wood, Khalik; Alias, Masitah

    2016-01-01

    The accumulation of radionuclides in soil is a greatest concerns due to their toxicity. This study investigated the vertical distribution of radionuclides and radiological assessment in a soil profile were collected in three different directions [North (N), North-East (NE) and South-East (SE)] within 40 km from Manjung district. All profile samples were collected down to 45cm at 7.5cm interval using hand auger. Soil density and radionuclides (40K, Th and U) concentrations were determined by gravimetric method and Energy Dispersive X-Ray Fluorescence (EDXRF) technique, respectively. The radionuclides concentrations was in decreasing order of 40K > Th > U. Soil quality assessment was carried out using Enrichment Factor (EF), Pollution Index (PI) and Geoaccumulation Index (I geo) where all radionuclides show significant enrichment (5 < EF < 20), PI classified as middle pollution classes and 0 < Igeo < 1, indicating moderately polluted, respectively. From the concentration of radionuclides, the radiological risk was calculated and the present result show external hazard index (Hex) is below than unity indicate low radiological risk.

  19. Triply degenerate quantum mixture of 41K, 40K and 6Li

    NASA Astrophysics Data System (ADS)

    Wu, Cheng-Hsun; Santiago, Ibon; Park, Jee Woo; Ahmadi, Peyman; Zwierlein, Martin

    2011-05-01

    We report the observation of a triply quantum degenerate mixture of 41K, 40K and 6Li atoms. It is demonstrated that bosonic 41K atom is an efficient coolant for sympathetic cooling of fermionic 40K and 6Li atoms. We also present our investigation of 41K and 40K, a Bose-Fermi mixture where a 12 G s-wave resonance is observed. Negligible differential gravitational sag between potassium isotopes makes this resonance an excellent candidate for studying unexplored properties of Bose- Fermi mixtures. The 40K and 6Li mixture provides access to strongly correlated Fermi-Fermi mixtures with imbalanced masses. This work was supported by the NSF, AFOSR-MURI, AFOSR-YIP, ARO-MURI, a grant from the Army Research Office with funding from the DARPA OLE program, the David and Lucille Packard Foundation and the Alfred P. Sloan Foundation.

  20. A 40 kDa protein of the inner membrane is the mitochondrial calcium uniporter

    PubMed Central

    De Stefani, Diego; Raffaello, Anna; Teardo, Enrico; Szabò, Ildikò; Rizzuto, Rosario

    2014-01-01

    Mitochondrial Ca2+ homeostasis plays a key role in the regulation of aerobic metabolism and cell survival1, but the molecular identity of the Ca2+ channel, the mitochondrial calcium uniporter2, was still unknown. We have identified in silico a protein (denominated MCU) that shares tissue distribution with MICU1, a recently characterized uniporter regulator3, coexists with uniporter activity in phylogeny and includes two trasmembrane domains in the sequence. siRNA silencing of MCU in HeLa cells drastically reduced mitochondrial Ca2+ uptake. MCU overexpression doubled the [Ca2+]mt rise evoked by IP3-generating agonists, thus significantly buffering the cytosolic elevation. The purified MCU protein exhibited channel activity in planar lipid bilayers, with electrophysiological properties and inhibitor sensitivity of the uniporter. A mutant MCU, in which two negatively-charged residues of the putative pore forming region were replaced, had no channel activity and reduced agonist-dependent [Ca2+]mt transients when overexpressed in HeLa cells. Overall, these data demonstrate that the identified 40 kDa protein is the channel responsible for Ruthenium Red-sensitive mitochondrial Ca2+ uptake, thus providing molecular basis for this process of utmost physiological and pathological relevance. PMID:21685888

  1. Antiandrogenic activity of phthalate mixtures: Validity of concentration addition

    SciTech Connect

    Christen, Verena; Crettaz, Pierre; Oberli-Schrämmli, Aurelia; Fent, Karl

    2012-03-01

    Phthalates and bisphenol A have very widespread use leading to significant exposure of humans. They are suspected to interfere with the endocrine system, including the androgen, estrogen and the thyroid hormone system. Here we analyzed the antiandrogenic activity of six binary, and one ternary mixture of phthalates exhibiting complete antiandrogenic dose–response curves, and binary mixtures of phthalates and bisphenol A at equi-effective concentrations of EC{sub 10}, EC{sub 25} and EC{sub 50} in MDA-kb2 cells. Mixture activity followed the concentration addition (CA) model with a tendency to synergism at high and antagonism at low concentrations. Isoboles and the toxic unit approach (TUA) confirmed the additive to synergistic activity of the binary mixtures BBP + DBP, DBP + DEP and DEP + BPA at high concentrations. Both methods indicate a tendency to antagonism for the EC{sub 10} mixtures BBP + DBP, BBP + DEP and DBP + DEP, and the EC{sub 25} mixture of DBP + BPA. A ternary mixture revealed synergism at the EC{sub 50}, and weak antagonistic activity at the EC{sub 25} level by the TUA. A mixture of five phthalates representing a human urine composition and reflecting exposure to corresponding parent compounds showed no antiandrogenic activity. Our study demonstrates that CA is an appropriate concept to account for mixture effects of antiandrogenic phthalates and bisphenol A. The interaction indicates a departure from additivity to antagonism at low concentrations, probably due to interaction with the androgen receptor and/or cofactors. This study emphasizes that a risk assessment of phthalates should account for mixture effects by applying the CA concept. -- Highlights: ► Antiandrogenic activity of mixtures of 2 and 3 phthalates are assessed in MDA-kb2 cells. ► Mixture activities followed the concentration addition model. ► A tendency to synergism at high and antagonism at low levels occurred.

  2. Peginterferon alfa-2a (40 kDa) monotherapy: a novel agent for chronic hepatitis C therapy.

    PubMed

    Zeuzem, S; Heathcote, J E; Martin, N; Nieforth, K; Modi, M

    2001-12-01

    Current therapy for hepatitis C remains far from optimal. The modification of IFN by the attachment of a polyethylene glycol (PEG) moiety has produced long-lasting IFNs. A 40 kDa branched peginterferon alfa-2a (40 kDa) (PEG-IFN alfa-2a) has unique pharmacokinetic and pharmacodynamic properties. PEG-IFN alfa-2a is absorbed in a sustained manner and its clearance is reduced substantially compared with IFN alfa-2a, resulting in sustained serum drug concentrations. These constant serum drug levels stay above the EC(50) values (effective concentration 50%) needed for antiviral, antiproliferative and immunomodulatory actions. Sustained virological responses were significantly greater in patients who received PEG-IFN alfa-2a versus IFN alfa-2a, with a similar side effect profile. Histological improvements were seen in patients who achieved sustained virological responses and were frequently observed among patients who did not achieve a virological response. The advantages of PEG-IFN alfa-2a were also seen in patients with cirrhosis or hepatitis C virus (HCV) genotype 1. PMID:11772316

  3. High-precision calculation of the branching ratio of the 40K decay constant.

    NASA Astrophysics Data System (ADS)

    Jourdan, F.

    2008-12-01

    40K is of great importance in Earth science, particularly for K/Ar, 40Ar/39Ar and K/Ca geochronology. The decay scheme of the 40K includes two different modes of decay, beta and electron capture followed by gamma-ray emission, which yield two different products, 40Ca* and 40Ar*. The relative probability that 40K decay following one of the two schemes is known as the branching ratio. An original method of calculation to obtain the value of the 40K branching ratio (λβ- /λtot) based on the K/Ar technique, is proposed. λβ- /λtot is obtained by combining the 40Ar*/40K value of Fish Canyon sanidine (FCs) secondary standard derived from four primary 40Ar/39Ar standards, with the current best estimates of the age of FCs and the value of the 40K total decay constant. The latest estimation of the 40K total decay constant and the age of FCs by Mundil et al. (2006), through comparison with U/Pb ages, yields a λβ- /λtot value of 89.59 ± 0.03% (1σ; relative error = ± 0.035%). Indirect measurement of the age of FCs by orbital tuning (Kuiper et al., 2008) combined with the value of 40K total decay constant measured by liquid scintillation counting by Kossert and Gunther (2004) yields a statistically indistinguishable value for the branching ratio of 89.61 ± 0.03%, with an average between the two values of 89.60 ± 0.04%. The method proposed here allows can easily be applied to further constrain the value of the 40K branching ratio as future refinements of the 40K decay constant and FCs age are produced, although it is expected that the adopted value will be close to λβ- /λtot = 89.60 ± 0.04%. Kossert and Gunther, 2004. Appl. Radiat. Isot. 60, 459-464. Kuiper et al., 2008. Science 320, 500-504. Mundil et al. 2006, Eos Trans. AGU, 87(52)

  4. Athletic Activity and Hormone Concentrations in High School Female Athletes

    PubMed Central

    Wojtys, Edward M.; Jannausch, Mary L.; Kreinbrink, Jennifer L.; Harlow, Siobán D.; Sowers, MaryFran R.

    2015-01-01

    Context: Physical activity may affect the concentrations of circulating endogenous hormones in female athletes. Understanding the relationship between athletic and physical activity and circulating female hormone concentrations is critical. Objective: To test the hypotheses that (1) the estradiol-progesterone profile of high school adolescent girls participating in training, conditioning, and competition would differ from that of physically inactive, age-matched adolescent girls throughout a 3-month period; and (2) athletic training and conditioning would alter body composition (muscle, bone), leading to an increasingly greater lean–body-mass to fat–body-mass ratio with accompanying hormonal changes. Design: Cohort study. Settings: Laboratory and participants' homes. Patients or Other Participants: A total of 106 adolescent girls, ages 14–18 years, who had experienced at least 3 menstrual cycles in their lifetime. Main Outcome Measure(s): Participants were prospectively monitored throughout a 13-week period, with weekly physical activity assessments and 15 urine samples for estrogen, luteinizing hormone, creatinine, and progesterone concentrations. Each girl underwent body-composition measurements before and after the study period. Results: Seventy-four of the 98 girls (76%) who completed the study classified themselves as athletes. Body mass index, body mass, and fat measures remained stable, and 17 teenagers had no complete menstrual cycle during the observation period. Mean concentrations of log(estrogen/creatinine) were slightly greater in nonathletes who had cycles of <24 or >35 days. Mean log(progesterone/creatinine) concentrations in nonathletes were less in the first half and greater in the second half of the cycle, but the differences were not statistically significant. Conclusions: A moderate level of athletic or physical activity did not influence urine concentrations of estrogen, progesterone, or luteinizing hormones. However, none of the

  5. Quantum dot-based concentric FRET configuration for the parallel detection of protease activity and concentration.

    PubMed

    Wu, Miao; Petryayeva, Eleonora; Algar, W Russ

    2014-11-18

    Protease expression, activity, and inhibition play crucial roles in a multitude of biological processes; however, these three aspects of their function are difficult for any one bioanalytical probe to measure. To help address this challenge, we report a multifunctional concentric Förster resonance energy transfer (FRET) configuration that combines two modes of biorecognition using aptamers and peptide substrates coassembled to a central semiconductor quantum dot (QD). The aptamer is sensitive to the concentration of protease and the peptide is sensitive to its hydrolytic activity. The role of the QD is to serve as a nanoscale scaffold and initial donor for energy transfer with both Cyanine 3 (Cy3) and Alexa Fluor 647 (A647) fluorescent dyes associated with the aptamer and peptide, respectively. Using thrombin as a model protease, we show that a ratiometric analysis of the emission from the QD, Cy3, and A647 permits discrimination between thrombin and thrombin-like activity, and distinguishes between active, reversibly inhibited, and irreversibly inhibited thrombin. Reliable quantitative results were obtained from a kinetic analysis of the changes in FRET. This concentric FRET format, which capitalizes on both the physical and optical properties of QDs, should be adaptable to other protease targets for which both peptide substrates and binding aptamers are known. It is thus expected to become valuable a tool for the real-time analysis of protease activity and regulation. PMID:25361050

  6. Chemical fertilizers as a source of (238)U, (40)K, (226)Ra, (222)Rn, and trace metal pollutant of the environment in Saudi Arabia.

    PubMed

    Alshahri, Fatimh; Alqahtani, Muna

    2015-06-01

    The specific activities of (238)U, (226)Ra, (40)K, and (222)Rn in chemical fertilizers were measured using gamma ray spectrometer and Cr-39 detector. In this study, 21 chemical fertilizers were collected from Eastern Saudi Arabian markets. The specific activities of (238)U ranged from 23 ± 0.5 to 3900 ± 195 Bq kg(-1); (226)Ra ranged from 5.60 ± 2.80 to 392 ± 18 Bq kg(-1); and (40)K ranged from 18.4 ± 3 to 16,476 ± 820 Bq kg(-1). The radon concentrations and the radon exhalation rates were found to vary from 3.20 ± 1.20 to 1532 ± 160 Bq m(-3) and from 1.60 to 774 mBq m(-2) h(-1), respectively. Radium equivalent activities (Raeq) were calculated for the analyzed samples to assess the radiation hazards arising due to the use of these chemical fertilizers in the agriculture soil. The Raeq for six local samples (nitrogen, phosphorous, and potassium (NPK) and single superphosphate (SSP)) and one imported sample (Sulfate of Potash (SOP)) were greater than the acceptable value 370 Bq kg(-1). The total air absorbed doses rates in air 1 m above the ground (D) were calculated for all samples. All samples, except one imported granule sample diammonium phosphate (DAP), were higher than the estimated average global terrestrial radiation of 55 nGy h(-1). The highest annual effective dose was in triple super phosphate (TSP) fertilizers (2.1 mSv y(-1)). The results show that the local TSP, imported SOP, and local NPK (sample 13) fertilizers were unacceptable for use as fertilizers in agricultural soil. Furthermore, the toxic elements and trace metals (Pb, Cd, Cr, Co, Ni, Hg, and As) were determined using atomic absorption spectrometer. The concentrations of chromium in chemical fertilizers were higher than the global values. PMID:25532871

  7. Phytochemical, antimicrobial, and antioxidant activities of different citrus juice concentrates.

    PubMed

    Oikeh, Ehigbai I; Omoregie, Ehimwenma S; Oviasogie, Faith E; Oriakhi, Kelly

    2016-01-01

    The search for new antimicrobial compounds is ongoing. Its importance cannot be overemphasized in an era of emerging resistant pathogenic organisms. This study therefore investigated the phytochemical composition and antioxidant and antimicrobial activities of different citrus juice concentrates. Fruit juices of Citrus tangerine (tangerine), Citrus paradisi (grape), Citrus limon (lemon), and Citrus aurantifolia (lime) were evaluated. Antimicrobial activities against five bacterial and three fungal strains were evaluated. The results revealed the presence of alkaloids, flavonoids, steroids, terpenoids, saponins, cardiac glycosides, and reducing sugars in all the juice concentrates. DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging capacities varied with tangerine and grape juices having better scavenging capacities than lemon and lime juices. Grape juice was observed to have a significantly higher (P < 0.05) ferric-reducing antioxidant potential (FRAP) value (364.2 ± 10.25 μmol/L Fe(II)/g of the extract) than the reference antioxidant, ascorbic acid (312.88 ± 5.61 μmol/L). Antimicrobial studies revealed differential antimicrobial activities against different microbial strains. Zones of inhibition ranging from 4 to 26 mm were observed for the antibacterial tests with 0-24 mm for antifungal test. Minimum inhibitory concentrations (MIC) and minimum bacteriostatic concentrations (MBC) for concentrates against bacterial strains ranged from 12.5 to 200 μg/mL. Lemon and lime juice concentrates had lower MIC and MBC values with orange and tangerine having the highest values. Minimum fungicidal concentrations ranged from 50 to 200 μg/mL. The results of this study suggest that these juice concentrates may have beneficial antimicrobial roles that can be exploited in controlling unwanted microbial growth. PMID:26788316

  8. Natural Radionuclide Activity Concentrations In Spas Of Argentina

    SciTech Connect

    Gnoni, G.; Czerniczyniec, M.; Canoba, A.; Palacios, M.

    2008-08-07

    Geothermal waters have been used on a large scale for bathing, drinking and medical purposes. These waters can contain natural radionuclides that may increase the exposure to people. In this work the most important natural radionuclide activity concentrations in different thermal spas of Argentina were measured to characterize waters and to evaluate the exposure of workers and members of the public.

  9. Pharmacokinetic properties of a 40 kDa branched polyethylene glycol-modified form of consensus interferon-alpha (PEG-CIFN) in rhesus monkeys.

    PubMed

    Du, Yu; Tian, Hong; Gao, Xiang-Dong; Yao, Wen-Bing

    2008-11-01

    The pharmacokinetic properties of a branched 40 kDa polyethylene glycol (PEG) conjugate formulation of consensus interferon-alpha (CIFN) was evaluated in rhesus monkeys following subcutaneous administration. Four groups of rhesus monkeys (n=6 per group) received 1250, 300 and 150 microg/kg of PEG-CIFN and 150 microg/kg CIFN, respectively. Serum concentrations of the interferons were measured with an antiviral activity assay at various time points after administration. The PK profiles of the pooled data were described by a noncompartmental method. Peak concentration of PEG-CIFN was observed at 27-31 h, followed by a prolonged decay in comparison with the unmodified CIFN, the PEG-CIFN had a 4-5-fold longer terminal half-life. The apparent clearance (dose(sc)/AUC) decreased from 150 mL/h/kg for CIFN to 19.0-45.5 mL/h/kg for PEG-CIFNs. The AUC was lower for PEG-CIFN than that for CIFN at the 150 microg/kg. PMID:18985796

  10. Diffusion of (226)Ra and (40)K radionuclides reproduced in underwater sedimentary columns in laboratory.

    PubMed

    Ligero, R A; Feria, F; Casas-Ruiz, M; Corredor, C

    2006-01-01

    The potential radiological impact of the increase of radioactive substances in the environment makes interesting the study of the migration of the contaminant radionuclides in soils and sediments, which are the last receiver system of these substances. By using a battery of sedimentary columns controlled in the laboratory, the diffusion of the (226)Ra and (40)K radionuclides has been studied, assessing their respective effective diffusion coefficients in a similar sedimentary medium. A decreasing temporal evolution is obtained, associated to the progressive 'fixation' of the radionuclides by the clay minerals of the sediment, followed by a constant tendency. A timescale of the 'fixation' by the sediment is determined, being of the order of days for (226)Ra and of the order of months for (40)K, so the progressive 'fixation' of (40)K by the clay minerals of the sediments is slower than in the case of (226)Ra. PMID:16488520

  11. Vertical and horizontal distribution of radionuclides (232Th, 238U and 40K) in sediment from Manjung coastal water area Perak, Malaysia

    NASA Astrophysics Data System (ADS)

    Abdullah, Anisa; Hamzah, Zaini; Saat, Ahmad; Wood, Ab. Khalik

    2016-01-01

    Distribution of radionuclides from anthropogenic activities has been widely studied in marine coastal area. Due to rapid population growth and socio-economic development in Manjung area such as coal fired power plant, iron foundries, port development, waste discharged from factories and agriculture runoff may contribute to increase in pollution rate. The radioactive materials from anthropogenic activities could deteriorate the quality of the marine ecosystem and thus lead to possible radiological health risk to the population. Radionuclides (232Th, 238U and 40K) content in surface and profile sediment from Manjung coastal area was determined in this study. Radionuclides in sediment from seven locations were collected using sediment core sampling and measurements were carried out using Energy Dispersive X-ray Fluorescence (EDXRF) spectroscopy. The results show that the concentration of radionuclides in surface sediment and distribution trend of depth vertical profile sediment generally varies depending on locations. Enrichment factors (EF), geo-accumulation index (Igeo) and pollution index (PI) were applied to determine level of pollution of this study area. The radiological risks related to human exposure were evaluated based on external hazard index (Hex).

  12. Kaman 40-kW wind system. Phase II. Fabrication and tests. Volume II. Technical report

    SciTech Connect

    Howes, H; Perley, R

    1981-01-01

    A program is underway to design, fabricate and test a horizontal axis Wind Turbine Generator (WTG) capable of producing 40 kW electrical output power in a 20 mph wind. Results are presented of the program effort covering fabrication and testing of the Wing Turbine Generator designed earlier. A minimum of difficulties were experienced during fabrication and, after successful completion of Contractor tests through 20 mph winds, the WTG was shipped to Rocky Flats, assembled and operated there. The 40 kW WTG is presently undergoing extended tests at Rockwell's Rocky Flats test facility.

  13. The influence of thoron on instruments measuring radon activity concentration.

    PubMed

    Michielsen, N; Bondiguel, S

    2015-11-01

    Thoron, the isotope 220 of radon, is a radionuclide whose concentration may influence the measurement of the activity concentration of (222)Rn in the air. If in the case of continuous and active sampling measuring instruments, using a pump for example, the influence of thoron on radon measurement is obvious and is taken into account in the apparatus, it is often assumed that in the case of a passive sampling, by diffusion through a filter for example, this thoron influence is negligible. This is due to the very short radioactive half-life of thoron, 55.6 s (3.82 d for (222)Rn), and the assumption that the diffusion time of thoron in the detection chamber is long enough beside that of the thoron half-life. The objective of this study is to check whether this assumption is true or not for different kinds of commercial electronic apparatus used to measure radon activity concentration from soil to dwellings. First of all, the devices were calibrated in activity concentration of radon, and then they were exposed to a controlled thoron atmosphere. The experiments concerning the thoron aimed to investigate the sensitivity to thoron in the radon measuring mode of the apparatus. Results of these experiments show that all devices have a very quick answer to thoron atmosphere, even though the sensitivities vary from one instrument to another. Results clearly show that this influence on radon measurement due to the thoron is observed also after the exposition because of the decay of (212)Pb and its progenies. In conclusion, the sensitivity to thoron in the radon measuring mode depends strongly on the type of instruments. The results of the present investigation show that for some apparatus, the influence of thoron cannot be disregarded especially when measuring radon in soil. PMID:25953787

  14. Differences in activation patterns between eccentric and concentric quadriceps contractions.

    PubMed

    McHugh, Malachy P; Tyler, Timothy F; Greenberg, Scott C; Gleim, Gilbert W

    2002-02-01

    Previous studies analysing electromyograms (EMGs) from indwelling electrodes have indicated that fast-twitch motor units are selectively recruited for low-intensity eccentric contractions. The aim of this study was to compare the frequency content of surface EMGs from quadriceps muscles during eccentric and concentric contractions at various contraction intensities. Electromyograms were recorded from the rectus femoris, vastus lateralis and vastus medialis muscles of 10 men during isokinetic (1.05 rad x s(-1)) eccentric and concentric knee extension contractions at 25%, 50%, 75% and 100% of maximal voluntary contraction (MVC) for each contraction mode. Additionally, isometric contractions (70 degrees) were performed at each intensity. The mean frequency and root mean square (RMS) of the surface EMG were computed. Mean frequency was higher for eccentric than concentric contractions at 25% (P < 0.01), 50% (P < 0.01) and 75% (P < 0.05) but not at 100% MVC. It increased with increasing contraction intensity for isometric (P < 0.001) and concentric (P < 0.01) contractions but not for eccentric contractions (P = 0.27). The EMG amplitude (RMS) increased with increasing contraction intensity similarly in each contraction mode (P < 0.0001). Higher mean frequencies for eccentric than concentric contractions at submaximal contraction intensities is consistent with more fast-twitch motor units being active during eccentric contractions. PMID:11811575

  15. Phytochemical concentrations and biological activities of Sorghum bicolor alcoholic extracts.

    PubMed

    Dia, Vermont P; Pangloli, Philipus; Jones, Lynsey; McClure, Angela; Patel, Anjali

    2016-08-10

    Sorghum is an important cereal with reported health benefits. The objectives of this study were to measure the biological activities of alcoholic extracts of ten sorghum varieties and to determine the association between the color of the extracts and their biological activities. Variation on concentrations of bioactives among sorghum varieties was observed with ethanolic extracts giving higher concentrations than methanolic extracts. The color of the extracts significantly correlated with the concentrations of bioactives and with nitric oxide scavenging activity. Freeze-dried ethanol extract is more potent than freeze-dried methanol extract and caused cytotoxicity to A27801AP and PTX-10 OVCA with ED50 values of 0.69 and 1.29 mg mL(-1), respectively. Pre-treatment of OVCA with ethanol extract led to chemosensitization to paclitaxel and the proliferation and colony formation of OVCA cells were reduced by 14.7 to 44.6% and 36.4 to 40.1%, respectively. Sorghum is a potential source of colorants with health promoting properties. This is the first report on the capability of sorghum alcoholic extracts to cause cytotoxicity and chemosensitize ovarian cancer cells in vitro. PMID:27406291

  16. Electric manipulation of ultracold polar ^40K^87Rb molecules in a magnetic field

    NASA Astrophysics Data System (ADS)

    Quéméner, Goulven; Bohn, John

    2009-05-01

    Ultracold fermionic polar molecules of ^40K^87Rb in their absolute rovibronic ground state (v=0,n=0,^1σ) have been created recently [1] in a magnetic trap and open new perspectives to create fermionic degenerate gases of polar molecules. To achieve this goal, it is very important to understand the collisional properties of such molecules under magnetic and electric fields. In our presentation, we investigate ground state fermionic ^40K^87Rb + ^40K^87Rb collisions in the presence of a magnetic field and explore the possibility to control these collisions when an electric field is applied. We will explore the main physical processes that can lead to such manipulation. This problem is complicated by the Zeeman and Stark splitting of all levels of the polar molecules and by the possibility of forming ^40K2 + ^87Rb2 chemical products. 1 - K.-K. Ni, S. Ospelkaus, M. H. G. de Miranda, A. Pe'er, B. Neyenhuis, J. J. Zirbel, S. Kotochigova, P. S. Julienne, D. S. Jin, and J. Ye, Science 322, 231 (2008).

  17. Sensitivity of large-scale neutrino detector to 40K geoneutrinos

    NASA Astrophysics Data System (ADS)

    Ungar, Yocheved

    2015-10-01

    Uranium, Thorium and Potassium are the primary radioactive constituents of Earth's mantle and crust. Neutrinos released during the decay of these radioactive elements can be used to directly study the bulk composition of Earth's interior. While existing detectors such as a KamLand and Borexino have detected 232Th and 238U, they do not have the sensitivity to observe the low energy (<1.8 MeV) 40K geoneutrinos. 40K geoneutrinos have been predicted to be the most abundant of the radioactive elements in Earth's interior and therefore are of particular interest. I am studying the feasibility of using a large scale (1000 ton) scintillator based detector to search for 40K geoneutrinos that interact with the scintillator through the process of antineutrino-electron scattering. I will present the results of calculations of neutrino flux predictions and the expected number of scattering events in a kiloton-scale detector as well as studies of backgrounds and their effect on the viability of detecting 40K geoneutrinos.

  18. Highly concentrated active nonlinear media based on oxides

    SciTech Connect

    Bakin, D.V.; Dorozhkin, L.M.; Krasilov, Yu.I.; Kuznetsov, N.T.; Potemkin, A.V.; Tadzhi-Aglaev, K.S.; Shestakov, A.V.

    1987-07-01

    Important characteristics of highly concentrated active nonlinear media were studied which were based on oxide compounds of phosphates, niobates, tantalates, and titanates of neodymium with alkaline earth metals. Compounds of the indicated classes were synthesized and their spectral luminescent and nonlinear optical properties were studied. Single crystals were grown from the selected compounds (5-8mm) and preliminary measurements of the laser and nonlinear optical parameters were taken. Formulas are given for materials that demonstrated high nonlinear and luminescent properties simultaneously. Spectroscopic and nonlinear optical properties of some oxygen compounds of rare earth elements are shown.

  19. Natural radioactivity concentration of peanuts in Osmaniye-Turkey

    SciTech Connect

    Akkurt, Iskender; Guenoglu, Kadir; Mavi, Betuel; Kara, Ayhan

    2012-09-06

    The peanut is grown in Osmaniye where located in southern Turkey. Due to it is grown underground, the measurements of natural radioactivity of peanuts become important. For this reason some peanut samples have been collected from different places of Osmaniye and the measurements of natural activity concentrations for {sup 40}K, {sup 226}Ra and {sup 232}Th in some peanuts samples have been carried out using a NaI(Tl) gamma-ray spectrometer. Activity of {sup 40}K was measured from its intensive line at 1460 keV, for {sup 226}Ra activity peak from {sup 214}Bi at 1760 keV and {sup 232}Th activity, peak from {sup 208}Tl at energy of 2610 keV was used.

  20. Dimerization in Highly Concentrated Solutions of Phosphoimidazolide Activated Mononucleotides

    NASA Technical Reports Server (NTRS)

    Kanavarioti, Anastassia

    1997-01-01

    Phosphoimidazolide activated ribomononucleotides (*pN) are useful substrates for the non-enzymatic synthesis of polynucleotides. However, dilute neutral aqueous solutions of *pN typically yield small amounts of dimers and traces of polymers; most of *pN hydrolyzes to yield nucleoside 5'-monophosphate. Here we report the self-condensation of nucleoside 5'-phosphate 2- methylimidazolide (2-MeImpN with N = cytidine, uridine or guanosine) in the presence of Mg2(+) in concentrated solutions, such as might have been found in an evaporating lagoon on prebiotic Earth. The product distribution indicates that oligomerization is favored at the expense of hydrolysis. At 1.0 M, 2-MelmpU and 2-MelmpC produce about 65% of oligomers including 4% of the 3',5'-Iinked dimer. Examination of the product distribution of the three isomeric dimers in a self-condensation allows identification of reaction pathways that lead to dimer formation. Condensations in a concentrated mixture of all three nucleotides (U,C,G mixtures) is made possible by the enhanced solubility of 2-MeImpG in such mixtures. Although percent yield of intemucleotide linked dimers is enhanced as a function of initial monomer concentration, pyrophosphate dimer yields remain practically unchanged at about 20% for 2-MelmpU, 16% for 2-MeImpC and 25% of the total pyrophosphate in the U,C,G mixtures. The efficiency by which oligomers are produced in these concentrated solutions makes the evaporating lagoon scenario a potentially interesting medium for the prebiotic synthesis of dimers and short RNAs.

  1. Nonionic surfactants enhancing bactericidal activity at their critical micelle concentrations.

    PubMed

    Tobe, Seiichi; Majima, Toshiaki; Tadenuma, Hirohiko; Suekuni, Tomonari; Sakai, Kenichi; Sakai, Hideki; Abe, Masahiko

    2015-01-01

    Bactericidal activities of benzalkonium chloride [also known as alkyldimethylbenzylammonium chloride (ADBAC)] containing nonionic surfactants such as methyl ester ethoxylates (MEE) with the alkyl group C8-C14 and oxyethylene (EO) group of average adduct number 3-15 were measured against Escherichia coli and Staphylococcus aureus. Sample solutions containing MEE in the vicinity of the critical micelle concentration exhibited a dramatic decrease in viable bacterial counts. MEE with an alkyl group of C12 and an oxyethylene group of lower adduct number exhibited little viable bacterial counts than those having higher EO adduct numbers. MEE with reduced EO adduct numbers increased fluorescence intensity in E. coli using the viability stain SYTO 9. Our results show that MEE molecules with low EO adduct numbers exhibited bactericidal activity by increasing the permeability of the E. coli cell membrane. Sample solution containing ADBAC and MEE molecules with lower EO adduct numbers also displayed higher zeta potentials. Moreover, ADBAC molecules incorporated into micelles of MEE with lower EO adduct numbers were adsorbed onto the surface of E. coli, which augmented bactericidal activity. PMID:25492231

  2. Evidence for superconductivity above 40 K in the La-Ba-Cu-O compound system

    NASA Technical Reports Server (NTRS)

    Chu, C. W.; Hor, P. H.; Meng, R. L.; Gao, L.; Huang, Z. J.

    1987-01-01

    An apparent superconducting transition with an onset temperature above 40 K has been detected under pressure in the La-Ba-Cu-O compound system synthesized directly from a solid-state reaction of La2O3, CuO, and BaCO3 followed by a decomposition of the mixture in a reduced atmosphere. The experiment is described and the results of effects of magnetic field and pressure are discussed.

  3. Operation result of 40kW class MCFC pilot plant

    SciTech Connect

    Saitoh, H.; Hatori, S.; Hosaka, M.; Uematsu, H.

    1996-12-31

    Ishikawajima-Harima Heavy Industries Co., Ltd. developed unique Molten Carbonate Fuel Cell (MCFC) system based on our original concept. To demonstrate the possibility of this system, based on MCFC technology of consigned research from New Energy and Industrial Technology Development Organization (NEDO) in Japan, we designed 40kW class MCFC pilot plant which had all equipments required as a power plant and constructed in our TO-2 Technical Center. This paper presents the test results of the plant.

  4. McDonnell 40-kW Giromill Wind System. Phase II. Fabrication and test

    SciTech Connect

    Brulle, R

    1980-06-01

    A 40 kW vertical axis windmill called a ''Giromill'' was fabricated, erected, and tested. The system design is described as well as some design changes made during fabrication. Manufacturing cost estimates are updated. Fabrication of the turbine blades, support arms, and fixed and rotating tower is described as well as the tests. Testing included control systems acceptance tests; Giromill system acceptance tests; structural, mechanical, control system and electric generation operational tests; and performance tests connected to the utility grid. (LEW)

  5. Comparative Activity of Ciprofloxacin, Levofloxacin and Moxifloxacin against Klebsiella pneumoniae, Pseudomonas aeruginosa and Stenotrophomonas maltophilia Assessed by Minimum Inhibitory Concentrations and Time-Kill Studies

    PubMed Central

    Grillon, Antoine; Schramm, Frédéric; Kleinberg, Magali; Jehl, François

    2016-01-01

    The aim of this study was to compare the in vitro susceptibility of Klebsiella pneumoniae, Pseudomonas aeruginosa and Stenotrophomonas maltophilia to three fluoroquinolones. The minimum inhibitory concentrations (MICs) to ciprofloxacin, levofloxacin and moxifloxacin were examined by E-test® for a total of 40 K. pneumoniae strains, 40 S. maltophilia strains and 40 P. aeruginosa strains. Then, the bactericidal activity of these fluoroquinolones was investigated on five strains of each bacterial species by means of time-kill curves. For K. pneumoniae and P. aeruginosa, the distance of the measured MIC from the clinical break-point is a good indicator of the bactericidal activity for ciprofloxacin and levofloxacin as obtained in our experiments. The lower the MIC, the better the bactericidal activity in term of CFU Log decreases. If MIC of ciprofloxacin and levofloxacin against the considered bacteria are far from clinical breakpoint, these two antibiotics are equivalent. According to our MIC50 and modal MIC, the breakpoints of both ciprofloxacin and levofloxacin seem to be somewhat high and data suggest reducing them. On S. maltophilia, none of the tested antibiotics showed a satisfactory activity. PMID:27257956

  6. Deconstructing honeybee vitellogenin: novel 40 kDa fragment assigned to its N terminus

    PubMed Central

    Havukainen, Heli; Halskau, Øyvind; Skjaerven, Lars; Smedal, Bente; Amdam, Gro V.

    2011-01-01

    Vitellogenin, an egg-yolk protein precursor common to oviparous animals, is found abundantly in honeybee workers – a caste of helpers that do not usually lay eggs. Instead, honeybee vitellogenin (180 kDa) participates in processes other than reproduction: it influences hormone signaling, food-related behavior, immunity, stress resistance and longevity. The molecular basis of these functions is largely unknown. Here, we establish and compare the molecular properties of vitellogenin from honeybee hemolymph (blood) and abdominal fat body, two compartments that are linked to vitellogenin functions. Our results reveal a novel 40 kDa vitellogenin fragment in abdominal fat body tissue, the main site for vitellogenin synthesis and storage. Using MALDI-TOF combined with MS/MS mass-spectroscopy, we assign the 40 kDa fragment to the N terminus of vitellogenin, whereas a previously observed 150 kDa fragment corresponded to the remainder of the protein. We show that both protein units are N glycosylated and phosphorylated. Focusing on the novel 40 kDa fragment, we present a homology model based on the structure of lamprey lipovitellin that includes a conserved β-barrel-like shape, with a lipophilic cavity in the interior and two insect-specific loops that have not been described before. Our data indicate that the honeybee fat body vitellogenin experiences cleavage unlike hemolymph vitellogenin, a pattern that can suggest a tissue-specific role. Our experiments advance the molecular understanding of vitellogenin, of which the multiple physiological and behavioral effects in honeybees are well established. PMID:21270306

  7. Variation of 40 kHz Signal Level in Relation to Sunrise, Sunset and Climatic Condition

    NASA Astrophysics Data System (ADS)

    Guha, A.; De, B. K.; Saha, A.; Das, T. K.

    2007-07-01

    The sunrise effect, sunset effect, the diurnal and seasonal variations are the characteristic feature of low frequency (LF) radio wave propagated over a large distance. The normal character has been found to be perturbed during rainy days. The amplitude of 40 kHz signal transmitted from Miyakoji station, Japan and received in North-East India is remarkably attenuated after the commencement of rain. On the basis of nature of attenuation the observed records have been classified into two different forms viz., F1 and F2. An analysis in this regard is represented in this paper.

  8. Observation of 2D Fermionic Mott Insulators of 40K with Single-Site Resolution

    NASA Astrophysics Data System (ADS)

    Cheuk, Lawrence W.; Nichols, Matthew A.; Lawrence, Katherine R.; Okan, Melih; Zhang, Hao; Zwierlein, Martin W.

    2016-06-01

    We report on the site-resolved observation of characteristic states of the two-dimensional repulsive Fermi-Hubbard model, using ultracold 40K atoms in an optical lattice. By varying the tunneling, interaction strength, and external confinement, we realize metallic, Mott-insulating, and band-insulating states. We directly measure the local moment, which quantifies the degree of on-site magnetization, as a function of temperature and chemical potential. Entropies per particle as low as 0.99 (6 )kB indicate that nearest-neighbor antiferromagnetic correlations should be detectable using spin-sensitive imaging.

  9. Metrological traceability for AC High-Voltage in Inmetro up to 40 kV

    NASA Astrophysics Data System (ADS)

    Vitorio, P. C. O.; de Lima, V. R.; Borges Filho, O.; de Souza, L. A. A.; Asencios, O. W. G.

    2016-07-01

    This paper refers to a project carried out in Inmetro aiming to provide internal metrological traceability for 60 Hz AC High-Voltage up to 40 kV. It presents details about the method used, its equations and obtained results. A capacitance and tanb bridge, with a built-in current comparator, was used in combination with two standard capacitors to calibrate a standard potential transformer (PT), both in ratio and phase angle. The results obtained by Inmetro showed good agreement with PTB ones, for the same PT. The maximum estimated uncertainty was 0,0049% for ratio error and 104 μrad for phase angle error.

  10. Modern Formation of Isotope System ( 40k, 137 Cs 226ra, 232th) In Exogenous Conditions Water Catch Basin of The White Sea

    NASA Astrophysics Data System (ADS)

    Yudakhin, F. N.; Kiseljov, G. P.; Bazhenov, A. V.

    Water modular basin of the White sea occupies a number of geological provinces. Northern and western parts are combined archey-paleozoic complex of metamorphogenic and magmatogenic mountain rock, which is blocked sporadically by low-power tundra and taiga soils. Southern, southeast and east is combined by sedimentary Paleozoic complex ? ?zen sinecliza, partially blocked by sea deposits of last freezing, on which the tundra's, southern tundra, northern and middle taiga settle down of ground actually. The ground deposits in rivers, lakes and White sea are formed from the all variety of mountain rocks, composing the territory, and up soil horizon. We investigated a system of isotopes (40K, 137Cs226Ra, 232Th,) in soils, bottom deposits of rivers, lakes and White sea, on more than 1500 tests, that allows to consider the modern spatial formation of isotope systems in soils and bottom deposits of the region. Findings about concentration of isotopes in genetic horizons of soils show the change of isotope sy stem depending on climatic zones and reflect an isotope status of environment, which basically delivers a material for bottom deposits of rivers and White sea. For bottom deposits of rivers characteristic is the following - from the washed out sand is occurs carrying out of all radionuclides, in silt sand and ooze there is an accumulation radionuclides, including 137Cs. That the silt deposits in the rivers water catch basin of the White sea occupy the subordinated situation among bottom deposits, radionucli des are actively taken out in White sea, where they collect. As a result of modern soil destruction (natural and technogenic influence) and sediment accumulation in water basin, there is a modern migration of radioactive isotopes in horizontal and vertical directions, therefore the new isotope systems are formed. Thus in soil horizons they are not steady and change at change of a climate and biological system, and in bottom deposits they are steady and further pass

  11. Sub-Doppler laser cooling of fermionic 40K atoms in three-dimensional gray optical molasses

    NASA Astrophysics Data System (ADS)

    Rio Fernandes, D.; Sievers, F.; Kretzschmar, N.; Wu, S.; Salomon, C.; Chevy, F.

    2012-12-01

    We demonstrate sub-Doppler cooling of 40K on the D1 atomic transition. Using a gray-molasses scheme, we efficiently cool a compressed cloud of 6.5 × 108 atoms from ˜4 mK to 20 μK in 8 ms. After transfer to a quadrupole magnetic trap, we measure a phase space density of ˜10-5. This technique offers a promising route for fast evaporation of fermionic 40K.

  12. The relation of seismic activity and radon concentration

    SciTech Connect

    Kulali, Feride E-mail: iskender@fef.sdu.edu.tr; Akkurt, İskender E-mail: iskender@fef.sdu.edu.tr; Vogiannis, Efstratios

    2014-10-06

    Radon, which is the largest source of natural ionizing radiation, reaches to surface as gas or dissolved form in the ground water. Emanation of radon can has a profile is disposed to increasing or decreasing depending on the effects of meteorological events or crust movements. In this work, the radon concentration in soil gas, which is transported from soil to AlphaGUARD, is continuously measured in Mytilene (Greece). A graph of radon concentration is prepared for comparison with simultaneous earthquake data. As a consequence of comparison, we determined that the radon concentration indicates anomalies before the earthquakes.

  13. Spatial distribution of radioisotope concentrations in the offshore water and sediment of the Bay of Bengal (Indian Ocean), Bangladesh.

    PubMed

    Bhuiyan, Md Khurshid Alam; Siddique, Mohammad Abdul Momin; Zafar, Mohammad; Mustafa Kamal, Abu Hena

    2014-01-01

    Concentrations of natural and fall-out radionuclides in the offshore seawater and sediment from some parts of the Bay of Bengal, Bangladesh, were determined using a coaxial germanium detector. The average activities of (238)U, (232)Th, (40)K and (137)Cs were recorded as 31.2±5.8, 51.9±9.4, 686.4±170.5 and 0.5±0.6 Bq kg(-1) dry weight, respectively, for sediment, and 4.8±1.2, 5.4±1.2 and 39.1±8.6 Bq L(-1) for (238)U, (232)Th and (40)K, respectively, in seawater. The concentration of (137)Cs in seawater was below the detection limit. The concentration of sediment (238)U was found to be positively correlated with (232)Th ([Formula: see text], p<0.05) and (40)K (r=0.96, p<0.01), while (232)Th was positively correlated with (40)K (r=0.91, p<0.05). In sediment, the concentration of (238)U was negatively correlated (r=-0.86, p<0.05) with sea depth. In the seawater sample, the only significant relationship found was between concentration of (232)Th and water depth (r=-0.86, p<0.05). One-factor analysis of variance (ANOVA) showed that the level of radioisotope concentrations of seawater and sediment was highly significant for (238)U (F=122, df=11, p=0.01), (232)Th (F=143, df=11, p=0.01) and (40)K (F=86, df=11, p=0.01). The results showed that the level of radioactivity decreased from coast to open sea. Imminent threat due to radioactivity was not observed in these parts of the Bay of Bengal. PMID:24090093

  14. Rotational Spectroscopy on Ultracold 23 Na40 K Ground State Molecules

    NASA Astrophysics Data System (ADS)

    Will, Sebastian; Park, Jee Woo; Yan, Zoe; Loh, Huanqian; Zwierlein, Martin

    2016-05-01

    Ultracold molecules with controllable dipolar long-range interactions will open up new routes for quantum simulation and the creation of novel states of matter. In particular, the molecules' rich internal degrees of freedom allow for versatile control of intermolecular interactions by applying static electric and microwave fields. Starting from an ultracold, spin-polarized ensemble of trapped fermionic 23 Na40 K molecules in the absolute ground state, we perform microwave spectroscopy on the first rotationally excited state for a range of magnetic and electric fields. Extracting the rotational and hyperfine coupling constants, we comprehensively understand the observed spectra. Following the coherent transfer of the entire ensemble of chemically stable 23 Na40 K molecules to the first rotationally excited state, we observe a lifetime of more than 3 sec, comparable to the lifetime in the rovibrational ground state. The collisional stability of excited rotational states opens up intriguing prospects for the control of intermolecular van-der-Waals interactions via electric fields.

  15. Creating Fermionic Ground State Molecules of 23Na40K with Strong Dipolar Interactions

    NASA Astrophysics Data System (ADS)

    Park, Jee; Wu, Cheng-Hsun; Schloss, Jennifer; Will, Sebastian; Zwierlein, Martin

    2013-05-01

    In our experiment, we work towards creating fermionic ground state molecules of 23Na40K with strong dipolar interactions. These molecules will be chemically stable in the rovibrational ground state, and will carry a large induced dipole moment of 2.72 Debye. Building up on our previous work, we have done photoassociation spectroscopy on the 23Na-40K mixture in order to understand the molecular excited state potentials and identify possible intermediate states for efficient STIRAP transfer of Feshbach molecules down to the absolute rovibrational ground state. In addition, our recent effort in doing two-photon spectroscopy to locate the absolute rovibrational ground state will be presented. Our work paves the way towards creating stable dipolar quantum gases, which will open up new avenues to quantum many-body phases with intriguing properties such as supersolidity and topological phases. This work was supported by the NSF, AFOSR-MURI and -PECASE, ARO-MURI, ONR YIP, DARPA YFA, a grant from the Army Research Office with funding from the DARPA OLE program and the David and Lucille Packard Foundation.

  16. Dynamic nuclear polarization at 40 kHz magic angle spinning.

    PubMed

    Chaudhari, Sachin R; Berruyer, Pierrick; Gajan, David; Reiter, Christian; Engelke, Frank; Silverio, Daniel L; Copéret, Christophe; Lelli, Moreno; Lesage, Anne; Emsley, Lyndon

    2016-04-21

    DNP-enhanced solid-state NMR spectroscopy under magic angle spinning (MAS) is rapidly developing into a powerful analytical tool to investigate the structure of a wide range of solid materials, because it provides unsurpassed sensitivity gains. Most developments and applications of DNP MAS NMR were so far reported at moderate spinning frequencies (up to 14 kHz using 3.2 mm rotors). Here, using a 1.3 mm MAS DNP probe operating at 18.8 T and ∼100 K, we show that signal amplification factors can be increased by up to a factor two when using smaller volume rotors as compared to 3.2 mm rotors, and report enhancements of around 60 over a range of sample spinning rates from 10 to 40 kHz. Spinning at 40 kHz is also shown to increase (29)Si coherence lifetimes by a factor three as compared to 10 kHz, substantially increasing sensitivity in CPMG type experiments. The contribution of quenching effects to the overall sensitivity gain at very fast MAS is evaluated, and applications are reported on a functionalised mesostructured organic-inorganic material. PMID:27035630

  17. Rare Super Cyclone Phailin in the Indian Ocean: Analysis of VIIRS High-Resolution IR Images and 40 kHz Sferics Data

    NASA Astrophysics Data System (ADS)

    Bhattacharya, A. B.; Pandit, J.; Bhattacharya, R.

    2014-10-01

    VIIRS high-resolution infrared (IR) images of the rare super cyclone Phailin of the Northern Indian Ocean as well as 40 kHz sferics data as recorded over Kalyani have been analyzed in this paper with a view to investigate the characteristics of the super cyclone. The maximum IR brightness temperature in the eye of the cyclone was pretty warm and it was illuminated by airglow. The Phailin was one of the strongest cyclones with a peak estimated intensity of 140 kts. Our round-the-clock sferics data also reveals remarkable changes in the sferics record on October 10, 2013, when the super cyclone was active.

  18. Variability of 137Cs and 40K soil-to-fruit transfer factor in tropical lemon trees during the fruit development period.

    PubMed

    Velasco, H; Cid, A S; Anjos, R M; Zamboni, C B; Rizzotto, M; Valladares, D L; Juri Ayub, J

    2012-02-01

    In this investigation we evaluate the soil uptake of (137)Cs and (40)K by tropical plants and their consequent translocation to fruits, by calculating the soil-to-fruit transfer factors defined as F(v) = [concentration of radionuclide in fruit (Bq kg(-1) dry mass)/concentration of radionuclide in soil (Bq kg(-1) dry mass in upper 20 cm)]. In order to obtain F(v) values, the accumulation of these radionuclides in fruits of lemon trees (Citrus limon B.) during the fruit growth was measured. A mathematical model was calibrated from the experimental data allowing simulating the incorporation process of these radionuclides by fruits. Although the fruit incorporates a lot more potassium than cesium, both radionuclides present similar absorption patterns during the entire growth period. F(v) ranged from 0.54 to 1.02 for (40)K and from 0.02 to 0.06 for (137)Cs. Maximum F(v) values are reached at the initial time of fruit growth and decrease as the fruit develops, being lowest at the maturation period. As a result of applying the model a decreasing exponential function is derived for F(v) as time increases. The agreement between the theoretical approach and the experimental values is satisfactory. PMID:22115437

  19. The active titration method for measuring local hydroxyl radical concentration

    NASA Technical Reports Server (NTRS)

    Sprengnether, Michele; Prinn, Ronald G.

    1994-01-01

    We are developing a method for measuring ambient OH by monitoring its rate of reaction with a chemical species. Our technique involves the local, instantaneous release of a mixture of saturated cyclic hydrocarbons (titrants) and perfluorocarbons (dispersants). These species must not normally be present in ambient air above the part per trillion concentration. We then track the mixture downwind using a real-time portable ECD tracer instrument. We collect air samples in canisters every few minutes for roughly one hour. We then return to the laboratory and analyze our air samples to determine the ratios of the titrant to dispersant concentrations. The trends in these ratios give us the ambient OH concentration from the relation: dlnR/dt = -k(OH). A successful measurement of OH requires that the trends in these ratios be measureable. We must not perturb ambient OH concentrations. The titrant to dispersant ratio must be spatially invariant. Finally, heterogeneous reactions of our titrant and dispersant species must be negligible relative to the titrant reaction with OH. We have conducted laboratory studies of our ability to measure the titrant to dispersant ratios as a function of concentration down to the few part per trillion concentration. We have subsequently used these results in a gaussian puff model to estimate our expected uncertainty in a field measurement of OH. Our results indicate that under a range of atmospheric conditions we expect to be able to measure OH with a sensitivity of 3x10(exp 5) cm(exp -3). In our most optimistic scenarios, we obtain a sensitivity of 1x10(exp 5) cm(exp -3). These sensitivity values reflect our anticipated ability to measure the ratio trends. However, because we are also using a rate constant to obtain our (OH) from this ratio trend, our accuracy cannot be better than that of the rate constant, which we expect to be about 20 percent.

  20. Concentration dependent differential activity of signalling molecules in Caenorhabditis elegans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Caenorhabditis elegans employs specific glycosides of the dideoxysugar ascarylose (the ‘ascarosides’) for monitoring population density/ dauer formation and finding mates. A synergistic blend of three ascarosides, called ascr#2, ascr#3 and ascr#4 acts as a dauer pheromone at a high concentration na...

  1. Three-Dimensional Concentration Measurements around Actively Tracking Blue Crabs

    NASA Astrophysics Data System (ADS)

    Dickman, B. D.; Jackson, J. L.; Weissburg, M. J.; Webster, D. R.

    2006-11-01

    Many aquatic arthropods locate food, suitable habitats, and mates solely through information extracted by chemical signals in their environment. Chemical plumes detected by larger animals are influenced by turbulence that creates an intermittent and unpredictable chemical stimulus environment. To link the stimulus pattern to behavior, we have developed a measurement system to quantify the instantaneous odor concentration surrounding a freely tracking blue crab through three-dimensional laser-induced fluorescence (3DLIF). A blue crab receives chemical stimulus at several locations, including the antennules near the mouth region and the distal tips of the legs and claws. Hence, three-dimensional measurements of the concentration field are required to link behavior to plume structure. During trials, crabs began their search 150 cm downstream of a source, and walking kinematics were recording simultaneously. The crabs were reversibly ``blindfolded'' during tracking to prevent aversive reactions to the intense laser light. Our experiments allow us to examine how hypothesized navigational cues, such as concentration bursts at the antennules and spatial asymmetry in concentration at the distributed chemosensory organs on the legs and claws, results in particular decisions during navigation.

  2. Complete genome sequence of Stackebrandtia nassauensis type strain (LLR-40K-21T)

    SciTech Connect

    Munk, Chris; Lapidus, Alla; Copeland, Alex; Jando, Marlen; Mayilraj, Shanmugam; Glavina Del Rio, Tijana; Nolan, Matt; Chen, Feng; Lucas, Susan; Tice, Hope; Cheng, Jan-Fang; Han, Cliff; Detter, John C.; Bruce, David; Goodwin, Lynne; Chain, Patrick; Pitluck, Sam; Göker, Markus; Ovchinikova, Galina; Pati, Amrita; Ivanova, Natalia; Mavromatis, Konstantinos; Chen, Amy; Palaniappan, Krishna; Land, Miriam; Hauser, Loren; Chang, Yun-Juan; Jeffries, Cynthia D.; Bristow, Jim; Eisen, Jonathan A.; Markowitz, Victor; Hugenholtz, Philip; Kyrpides, Nikos C.; Klenk, Hans-Peter

    2009-12-30

    Stackebrandtia nassauensis Labeda and Kroppenstedt (2005) is the type species of the genus Stackebrandtia, and a member of the actinobacterial family Glycomycetaceae. Stackebrandtia currently contains two species, which are differentiated from Glycomyces spp. by cellular fatty acid and menaquinone composition. Strain LLR-40K-21T is Gram-positive, aerobic, and nonmotile, with a branched substrate mycelium and on some media an aerial mycelium. The strain was originally isolated from a soil sample collected from a road side in Nassau, Bahamas. We describe the features of this organism, together with the complete genome sequence and annotation. Lastly, this is the first complete genome sequence of the actinobacterial suborder Glycomycineae. The 6,841,557 bp long single replicon genome with its 6487 protein-coding and 53 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.

  3. Development and calibration of a portable radon sampling system for groundwater 222Rn activity concentration measurements.

    PubMed

    Lucas, Fabio de Oliveira; de Oliveira, Igor José Chaves; Ribeiro, Fernando Brenha

    2009-10-01

    The assembling of a system for field sampling and activity concentration measurement of radon dissolved in groundwater is described. Special attention is given in presenting the calibration procedure to obtain the radon activity concentration in groundwater from the raw counting rate registered in a portable scintillation detector and in establishing the precision of the activity concentration measurements. A field procedure was established and the system tested during one year of monthly observations of (222)Rn activity concentration in groundwater drawn from two wells drilled on metamorphic rocks exposed at Eastern São Paulo State, Brazil. The observed mean (222)Rn activity concentrations are 374Bq/dm(3) in one well and about 1275Bq/dm(3) in the other one. In both wells the (222)Rn activity concentrations showed a seasonal variation similar to variations previously reported in the literature for the same region. PMID:19608307

  4. Russian Activities in Space Photovoltaic Power Modules with Concentrators

    NASA Technical Reports Server (NTRS)

    Andreev, Vyacheslav M.; Rumyantsev, Valeri D.

    2004-01-01

    Space concentrator modules with point-and line-focus Fresnel lenses and with reflective parabolic troughs have been developed recently at Ioffe Physico-Technical Institute. PV receivers for these modules are based: on the single junction LPE and MOCVD AlGaAs/GaAs solar cells characterized by AM0 efficiencies of 23.5 - 24% at 20 - 50 suns and 24 - 24.75 at 50 - 200 suns; on the mechanically stacked tandem AlGaAs/GaAs-GaSb cells with efficiency of 27 - 28 at 20 - 100 suns. MOCVD AlGaAs/GaAs cells with internal Bragg reflector have shown a higher radiation resistance as compared to a traditional structure. Monolithic two-terminal tandems AlGaAs (top)-GaAs (bottom) for space application and GaSb (top) - InGaAsSb (bottom) for TRV application are under development as well.

  5. Temporal variations in plasma vitamin K and lipid concentrations and clotting factor activity in humans.

    PubMed

    Kamali, F; Edwards, C; Wood, P; Wynne, H A; Kesteven, P

    2001-11-01

    There is no information available on temporal variability in plasma vitamin K concentrations and its relationship to coagulation processes. We investigated the possible existence of temporal changes in plasma vitamin K and lipid concentrations and activity of clotting factors II, VII, IX, and X and relationships between these variables. Plasma vitamin K and lipid concentrations and clotting factor activity were measured at four-hour intervals for 28 hours in a group of healthy volunteers. Temporal variations existed in plasma vitamin K concentrations, with a mean maximum at 22:00 hr and a mean minimum (32% of the maximum) at 10:00 hr. Plasma triglycerol concentrations mirrored the changes in vitamin K concentrations. Mean factor VII activity was positively correlated with mean total plasma cholesterol concentrations (r = 0.714; P < 0.0001) and with mean plasma low density lipoprotein (LDL) cholesterol concentrations (r = 0.461; P < 0.0001). No distinct correlations were found between plasma vitamin K concentrations and either high density lipoprotein (HDL) or LDL cholesterol concentrations, or between triglycerol, HDL, or LDL cholesterol concentrations and functional activity of factors II, IX, and X. Plasma vitamin K concentrations did not correlate with the functional activity of any of the clotting factors. The presence of a correlation between plasma cholesterol concentrations and factor VII activity for blood samples collected at four-hour intervals suggests that plasma cholesterol concentrations may have a more acute effect on factor VII activity. Temporal variations in plasma vitamin K concentrations indicate that a single time point measurement may be an inappropriate method of establishing vitamin K status in an individual. PMID:11754396

  6. Calculating Capstone depleted uranium aerosol concentrations from beta activity measurements.

    PubMed

    Szrom, Frances; Falo, Gerald A; Parkhurst, Mary Ann; Whicker, Jeffrey J; Alberth, David P

    2009-03-01

    Beta activity measurements were used as surrogate measurements of uranium mass in aerosol samples collected during the field testing phase of the Capstone Depleted Uranium (DU) Aerosol Study. These aerosol samples generated by the perforation of armored combat vehicles were used to characterize the DU source term for the subsequent Human Health Risk Assessment (HHRA) of Capstone aerosols. Establishing a calibration curve between beta activity measurements and uranium mass measurements is straightforward if the uranium isotopes are in equilibrium with their immediate short-lived, beta-emitting progeny. For DU samples collected during the Capstone study, it was determined that the equilibrium between the uranium isotopes and their immediate short-lived, beta-emitting progeny had been disrupted when penetrators had perforated target vehicles. Adjustments were made to account for the disrupted equilibrium and for wall losses in the aerosol samplers. Values for the equilibrium fraction ranged from 0.16 to 1, and the wall loss correction factors ranged from 1 to 1.92. This paper describes the process used and adjustments necessary to calculate uranium mass from proportional counting measurements. PMID:19204483

  7. Calculating Capstone Depleted Uranium Aerosol Concentrations from Beta Activity Measurements

    SciTech Connect

    Szrom, Fran; Falo, Gerald A.; Parkhurst, MaryAnn; Whicker, Jeffrey J.; Alberth, David P.

    2009-03-01

    Beta activity measurements were used as surrogate measurements of uranium mass in aerosol samples collected during the field testing phase of the Capstone Depleted Uranium (DU) Aerosol Study. These aerosol samples generated by the perforation of armored combat vehicles were used to characterize the depleted uranium (DU) source term for the subsequent human health risk assessment (HHRA) of Capstone aerosols. Establishing a calibration curve between beta activity measurements and uranium mass measurements is straightforward if the uranium isotopes are in equilibrium with their immediate short-lived, beta-emitting progeny. For DU samples collected during the Capstone study, it was determined that the equilibrium between the uranium isotopes and their immediate short lived, beta-emitting progeny had been disrupted when penetrators had perforated target vehicles. Adjustments were made to account for the disrupted equilibrium and for wall losses in the aerosol samplers. Correction factors for the disrupted equilibrium ranged from 0.16 to 1, and the wall loss correction factors ranged from 1 to 1.92.

  8. 40K-40Ca systematics as a Tracer of Silicate Weathering: A Himalayan case study

    NASA Astrophysics Data System (ADS)

    Davenport, Jesse; Caro, Guillaume; France-Lanord, Christian

    2015-04-01

    This study investigates the use of the 40K-40Ca system as a tracer to better quantify the contributions of silicate and carbonate lithologies in the dissolved load of major Himalayan rivers. Previous work using Sr isotopes as a proxy for silicate weathering has been complicated by the redistribution of radiogenic 87Sr between silicate and carbonate lithologies, particularly in the Lesser Himalaya, where dolomites exhibit 87Sr/86Sr ratios as high as 0.85. The 40Ca signature of carbonates, on the other hand, appears to be remarkably resistant to metamorphism and dolomitization [1]. It was therefore anticipated that the 40K-40Ca system could circumvent issues associated with such secondary events, and yield more robust constraints on the relative contribution of silicate vs. carbonate lithologies in dissolved river loads. The main difficulty in applying the 40K-40Ca decay scheme as a tracer lies in the analytical precision required to measure small variations (~1 ɛ-unit) on the large 40Ca isotope (96.9%). This difficulty can now be overcome using the Finnigan Triton TIMS, which allows measurements of the 40Ca/44Ca ratio with external precision of 0.35 ɛ-unit in multidynamic mode. Using this method, we generated high-precision 40Ca data on carbonates/dolomites, bedload sediments, dissolved load, and clay samples originating from and representing the main litho-tectonic units of the Himalaya. Our results show that metamorphosed dolomites from the Lesser Himalaya (LH) exhibit no radiogenic 40Ca excess despite highly variable 87Sr/86Sr signatures (0.73-0.85). Thus, all Himalayan carbonates appear to be characterized by a homogeneous ɛ40Ca=0. In contrast, silicate material is radiogenic, with ɛ40Ca averaging +1 in the Tethyan Sedimentary Series (TSS), +1.6 in the High Himalaya crystalline (HHC) and +4 ɛ-units in the LH. Results obtained from a series of 35 Himalayan rivers (including the Brahmaputra, Ganga and its main tributaries) show that ɛ40Ca in the

  9. Melatonin concentrations in the two jugular veins, and relationship with the seasonal reproductive activity in goats.

    PubMed

    Zarazaga, L A; Celi, I; Guzmán, J L; Malpaux, B

    2010-07-15

    The authors investigated whether melatonin concentrations vary between the two jugular veins and whether absolute (nocturnal) or relative (nocturnal/diurnal ratio) plasma melatonin concentrations are associated with seasonal reproductive activity measured by oestrus or ovulatory activity in Payoya goats. Thirty-two adult Payoya goats were penned under natural photoperiod. Oestrus activity was tested daily using aproned males-twice a week plasma was sampled for progesterone. Melatonin plasma concentrations were studied at each equinox and solstice of the year in jugular samples taken simultaneously by venipuncture. Nocturnal and diurnal plasma melatonin concentrations from each jugular vein were assessed in 3 and 2 plasma samples per goat, respectively, taken at hourly intervals in each period. No differences in melatonin concentrations between the two veins were observed, but there was a significant interaction (P < 0.001) between jugular vein and animal in nocturnal melatonin concentrations. There was no effect of sampling period on melatonin concentrations and the coefficient of correlation between sampling periods was very high. The analyses performed indicated that neither absolute nor relative melatonin concentrations were related with the dates of onset or end of ovulatory/oestrus activity. Therefore, we concluded that in goats (1) melatonin concentrations are highly variable between jugular veins in the same individual but not in the general population, (2) melatonin concentrations are highly repeatable for each individual, and (3) absolute and relative amplitudes of melatonin concentrations are not linked to the seasonal breeding activity in Mediterranean goats. PMID:20451998

  10. Classical Nuclear Hormone Receptor Activity as a Mediator of Complex Concentration Response Relationships for Endocrine Active Compounds

    PubMed Central

    Cookman, Clifford J.; Belcher, Scott M.

    2014-01-01

    Nonmonotonic concentration response relationships are frequently observed for endocrine active ligands that act via nuclear receptors. The curve of best fit for nonmonotonic concentration response relationships are often inverted U-shaped with effects at intermediate concentrations that are different from effects at higher or lower concentrations. Cytotoxicity is a major mode of action responsible for inverted U-shaped concentration response relationships. However, evidence suggests that ligand selectivity, activation of multiple molecular targets, concerted regulation of multiple opposing endpoints, and multiple ligand binding sites within nuclear receptors also contribute to nonmonotonic concentration response relationships of endocrine active ligands. This review reports the current understanding of mechanisms involved in classical nuclear receptor mediated nonmonotonic concentration response relationships with a focus on studies published between 2012 and 2014. PMID:25299165

  11. Cryogenic System for Interferometric Measurement of Dimensional Changes at 40 K: Design and Performance

    NASA Technical Reports Server (NTRS)

    Blake, Peter; Miller, Franklin; Zukowski, Tim; Canavan, Edgar R.; Crane, Allen; Madison, Tim; Miller, David

    2007-01-01

    This report describes the facility, experimental methods, characterizations, and uncertainty analysis of the Cryo Distortion Measurement Facility (CDMF) at the Goddard Space Flight Center (GSFC). This facility is designed to measure thermal distortions of structural elements as the temperature is lowered from 320K to below 40 K over multiple cycles, and is capable of unattended running and data logging. The first measurement is to be the change in length and any bending of composite tubes with Invar end-fittings. The CDMF includes a chamber that is efficiently cooled with two cryo-coolers (one single-stage and one two-stage) rather than with liquid cryogens. Five optical ports incorporate sapphire radiation shields - transparent to the interferometer - on each of two shrouds and a fused silica vacuum-port window. The change in length of composite tubes is monitored continuously with displacement-measuring interferometers; and the rotations, bending, and twisting are measured intermittently with theodolites and a surface-figure interferometer. Nickel-coated invar mirrors and attachment mechanisms were developed and qualified by test in the CDMF. The uncertainty in measurement of length change of 0.4 m tubes is currently estimated at 0.9 micrometers.

  12. Long Hyperfine Coherence Time of Ultracold Fermionic 23 Na40 K Molecules

    NASA Astrophysics Data System (ADS)

    Park, Jee Woo; Yan, Zoe; Loh, Huanqian; Will, Sebastian; Zwierlein, Martin

    2016-05-01

    Ultracold molecules created and trapped at sub uK temperatures allow the full control of the molecule's external and internal degrees of freedom down to a single hyperfine state. In particular, an ensemble of molecules all initialized in a single rotational and hyperfine state can be prepared and be coherently addressed using microwave fields. In this talk, we report on the observation of long coherence time between two hyperfine states of fermionic 23 Na40 K molecules in the ro-vibronic ground state (v = 0 , J = 0). A direct two-photon microwave transition via the J = 1 state is used to prepare a superposition of two lowest hyperfine states of J = 0 , and we perform Ramsey spectroscopy as a direct probe of phase coherence between these states. The fermionic nature of the molecules and the lack of electronic angular momentum in the ro-vibronic ground state heavily suppress the decoherence from collisions and external fields, respectively, and we observe long coherence times upto 0.5 sec for this hyperfine superposition state. The observed long coherence time is a crucial step for applications of trapped dipolar molecules in quantum information processing schemes.

  13. Natural and anthropogenic radionuclide activity concentrations in the New Zealand diet.

    PubMed

    Pearson, Andrew J; Gaw, Sally; Hermanspahn, Nikolaus; Glover, Chris N

    2016-01-01

    To support New Zealand's food safety monitoring regime, a survey was undertaken to establish radionuclide activity concentrations across the New Zealand diet. This survey was undertaken to better understand the radioactivity content of the modern diet and also to assess the suitability of the current use of milk as a sentinel for dietary radionuclide trends. Thirteen radionuclides were analysed in 40 common food commodities, including animal products, fruits, vegetables, cereal grains and seafood. Activity was detected for (137)Caesium, (90)Strontium and (131)Iodine. No other anthropogenic radionuclides were detected. Activity concentrations of the three natural radionuclides of Uranium and the daughter radionuclide (210)Polonium were detected in the majority of food sampled, with a large variation in magnitude. The maximum activity concentrations were detected in shellfish for all these radionuclides. Based on the established activity concentrations and ranges, the New Zealand diet contains activity concentrations of anthropogenic radionuclides far below the Codex Alimentarius guideline levels. Activity concentrations obtained for milk support its continued use as a sentinel for monitoring fallout radionuclides in terrestrial agriculture. The significant levels of natural and anthropogenic radionuclide activity concentrations detected in finfish and molluscs support undertaking further research to identify a suitable sentinel for New Zealand seafood monitoring. PMID:26094571

  14. Effect of the active-ion concentration on the lasing dynamics of holmium fibre lasers

    SciTech Connect

    Kurkov, Andrei S; Sholokhov, E M; Marakulin, A V; Minashina, L A

    2010-12-09

    The lasing dynamics of fibre lasers with a core based on quartz glass doped with holmium ions to concentrations in the range of 10{sup 19}-10{sup 20} cm{sup -3} is investigated. It is shown that fibre lasers with a high concentration of active holmium ions generate pulses, but a decrease in the holmium concentration changes the lasing from pulsed to cw regime. At the same time, a decrease in the active-ion concentration and the corresponding increase in the fibre length in the cavity reduce the lasing efficiency. (lasers)

  15. Giant Anharmonicity and Theory of Surprising BCS Superconductivity in MgB2 at 40 K

    NASA Astrophysics Data System (ADS)

    Yildirim, Taner

    2002-03-01

    The recent surprise discovery of superconductivity in MgB2 at 40 K has stimulated a great deal of research on this intercalated grahite-like system. Sparked by this discovery, we set out to unlock the structural secrets and, in particular, to reveal the origin of the high Tc in MgB_2; an electron-phonon or other exotic mechanism? To answer this fundamental question, we calculated T_c, its pressure dependence for uni- and biaxial compressions, and the isotope effect from the electronic band structure and lattice dynamics of MgB2 using density functional theory[1-2]. The calculated phonon density of states (DOS) are in excellent agreement with the inelastic neutron scattering measurements. We find that the in-plane boron phonons near the zone-center are very anharmonic and strongly coupled to the planar B sigma bands near the Fermi level. The boron mass and pressure dependence of this mode is found to be the key to quantitatively explaining the observed high T_c, the total isotope effect, and the pressure dependence of T_c. We propose that a stringent test on the hole and phonon based theories of the superconductivity in MgB2 would be a measurement of the biaxial ab-compression dependence of T_c. In collobration with Oguz Gulseren, NIST and UPENN [1] T. Yildirim et. al., Phys. Rev. Lett. 87, 037001 (2001). [2] For details, see http://www.ncnr.nist.gov/staff/taner/mgb2

  16. Natural radionuclide concentrations in two phosphate ores of east Algeria.

    PubMed

    Lakehal, Ch; Ramdhane, M; Boucenna, A

    2010-05-01

    Ore is considered as an important source of many elements such as the iron, phosphorus, and uranium. Concerning the natural radionuclides, their concentrations vary from an ore to other depending on the chemical composition of each site. In this work, two phosphate ores found in East of Algeria have been chosen to assess the activity concentration of natural radionuclides represented mainly by three natural radioactive series (238)U, (235)U and (232)Th, and the primordial radionuclide (40)K where they were determined using ultra-low background, high-resolution gamma-ray spectroscopy. The measured activity concentrations of radioactive series ranged from 6.2 +/- 0.4 to 733 +/- 33 Bq.kg(-1) for the (232)Th series, from 249 +/- 16 to 547 +/- 39 Bq.kg(-1) for the (238)U series, around 24.2 +/- 2.5 Bq.kg(-1) for the (235)U series, and from 1.4 +/- 0.2 to 6.7 +/- 0.7 Bq.kg(-1) for (40)K. To assess exposure to gamma radiation in the two ores, from specific activities of (232)Th, (40)K and (226)Ra, three indexes were determined: Radium equivalent (Ra(eq)), external and internal hazard indexes (H(ex) and H(in)), their values ranged from 831 +/- 8 to 1298 +/- 14 Bq.kg(-1) for Ra(eq), from 2.2 +/- 0.4 to 3.5 +/- 0.7 Bq.kg(-1) for H(ex), and from 4.2 +/- 0.7 to 4.5 +/- 0.7 Bq.kg(-1) for H(in). PMID:20303630

  17. Determination of environmental radioactivity (238U, 232Th and 40K) and indoor natural background radiation level in Chennai city (Tamilnadu State), India.

    PubMed

    Babai, K S; Poongothai, S; Punniyakotti, J

    2013-01-01

    An extensive study on the determination of the natural radioactivity ((238)U, (232)Th and (40)K) levels in soil samples of Chennai city, India has been undertaken and the results of the same are compared with the levels reported in other Indian cities as well as other parts of the world. The radioactivity content in the soil samples, the absorbed dose rate, annual effective dose equivalent, radium equivalent activity, internal and external hazard indices were calculated and compared with UNSCEAR 2000 recommended values. In addition to the above, mapping of indoor natural background gamma radiation levels has been made using thermo luminescent dosemeters throughout Chennai city and the same are reported. PMID:22847868

  18. The use of portable equipment for the activity concentration index determination of building materials: method validation and survey of building materials on the Belgian market.

    PubMed

    Stals, M; Verhoeven, S; Bruggeman, M; Pellens, V; Schroeyers, W; Schreurs, S

    2014-01-01

    The Euratom BSS requires that in the near future (2015) the building materials for application in dwellings or buildings such as offices or workshops are screened for NORM nuclides. The screening tool is the activity concentration index (ACI). Therefore it is expected that a large number of building materials will be screened for NORM and thus require ACI determination. Nowadays, the proposed standard for determination of building material ACI is a laboratory analyses technique with high purity germanium spectrometry and 21 days equilibrium delay. In this paper, the B-NORM method for determination of building material ACI is assessed as a faster method that can be performed on-site, alternative to the aforementioned standard method. The B-NORM method utilizes a LaBr3(Ce) scintillation probe to obtain the spectral data. Commercially available software was applied to comprehensively take into account the factors determining the counting efficiency. The ACI was determined by interpreting the gamma spectrum from (226)Ra and its progeny; (232)Th progeny and (40)K. In order to assess the accuracy of the B-NORM method, a large selection of samples was analyzed by a certified laboratory and the results were compared with the B-NORM results. The results obtained with the B-NORM method were in good correlation with the results obtained by the certified laboratory, indicating that the B-NORM method is an appropriate screening method to assess building material ACI. The B-NORM method was applied to analyze more than 120 building materials on the Belgian market. No building materials that exceed the proposed reference level of 1 mSv/year were encountered. PMID:24158046

  19. 13 CFR 120.828 - Minimum level of 504 loan activity and restrictions on portfolio concentrations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 13 Business Credit and Assistance 1 2012-01-01 2012-01-01 false Minimum level of 504 loan activity and restrictions on portfolio concentrations. 120.828 Section 120.828 Business Credit and Assistance... concentrations. (a) A CDC is required to receive SBA approval of at least four 504 loan approvals during...

  20. 13 CFR 120.828 - Minimum level of 504 loan activity and restrictions on portfolio concentrations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 13 Business Credit and Assistance 1 2014-01-01 2014-01-01 false Minimum level of 504 loan activity and restrictions on portfolio concentrations. 120.828 Section 120.828 Business Credit and Assistance... concentrations. (a) A CDC is required to receive SBA approval of at least four 504 loan approvals during...

  1. 13 CFR 120.828 - Minimum level of 504 loan activity and restrictions on portfolio concentrations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 13 Business Credit and Assistance 1 2013-01-01 2013-01-01 false Minimum level of 504 loan activity and restrictions on portfolio concentrations. 120.828 Section 120.828 Business Credit and Assistance... concentrations. (a) A CDC is required to receive SBA approval of at least four 504 loan approvals during...

  2. 13 CFR 120.828 - Minimum level of 504 loan activity and restrictions on portfolio concentrations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false Minimum level of 504 loan activity and restrictions on portfolio concentrations. 120.828 Section 120.828 Business Credit and Assistance... concentrations. (a) A CDC is required to receive SBA approval of at least four 504 loan approvals during...

  3. Effect of Radionuclide Activity Concentration on PET-CT Image Uniformity

    PubMed Central

    Hasford, Francis; Wyk, Bronwin Van; Mabhengu, Thulani; Vangu, Mboyo Di Tamba; Kyere, Augustine Kwame; Amuasi, John Humphrey

    2016-01-01

    Assessment of radionuclide activity concentration on positron emission tomography-computedr tomography (PET-CT) image uniformity has been carried out quantitatively. Tomographic PET-CT images of cylindrical phantom containing F-18 fluorodeoxyglucose (FDG) activity concentration was acquired and used for the assessment. Activity concentrations were varied and PET-CT images were acquired at the constant acquisition parameters of time, matrix size, and reconstruction algorithm, respectively. Using midtransaxial image slices, quantitative index of nonuniformity (NU), and coefficient of uniformity variation were estimated for the different activity concentrations. Maximum NUs of 17.6%, 26.3%, 32.7%, 36.2%, and 38.5% were estimated for activity concentrations of 16.87 kBq/mL, 14.06 kBq/mL, 11.25 kBq/mL, 8.43 kBq/mL, and 5.62 kBq/mL, respectively. The coefficient of uniformity variation established an inverse quadratic relationship with activity concentration. Activity concentrations of 16.87 kBq/mL, 14.06 kBq/mL, 11.25 kBq/mL, 8.43 kBq/mL, and 5.62 kBq/mL produced uniformity variations of 1.47%, 2.52%, 4.23%, 5.12%, and 4.98%, respectively. Increasing activity concentration resulted in decreasing coefficient of uniformity and hence, an increase in image uniformity. The uniformity estimates compared well with the standards set internationally. PMID:27134558

  4. 40K-40Ca systematics as a tracer of silicate weathering in the Himalayas

    NASA Astrophysics Data System (ADS)

    Davenport, J.; Caro, G.; France-Lanord, C.

    2015-12-01

    Increased weathering resulting from the uplift of the Himalayan Mountains has been cited as one cause (among others) of late Cenozoic cooling. Orogenic uplift generally results in the development of high relief and enhanced erosion, which in turn induces rapid chemical weathering and uptake of atmospheric CO2. Tracing these processes can be accomplished using techniques such as the budget of major element and/or Sr isotopes of the dissolved load. However, in the Himalaya, Sr isotopic compositions are extreme even in carbonate phases, making it difficult to produce realistic estimates of silicate and carbonate inputs to Himalayan rivers. In this study, we explore the potential of the 40K-40Ca system to quantify the relative contributions of silicate and carbonate weathering to river dissolved loads. To this end, we analysed a suite of 40 rivers draining the main litho-tectonic units of the Himalaya, sediments, bedrock, mineral separates and soil and gravel. Our results show that Himalayan carbonates exhibit no radiogenic 40Ca excess despite highly variable 87Sr/86Sr signatures (0.73-0.85). The silicate fraction of bedload sediments is variably radiogenic (+1 to +4), with ɛ40Ca correlating with the 87Sr/86Sr ratio. Analyses of plagioclase, biotite and muscovite separates from a HHC gneiss and greywacke show homogeneous ɛ40Ca despite highly variable K/Ca ratios, indicating recent metamorphic equilibration on a mineral scale. Thus, incongruent weathering of high K/Ca minerals should not represent a significant factor when considering the transfer of radiogenic calcium to the dissolved load. The ɛ40Ca signatures of dissolved river material are significantly influenced by silicate lithologies, and range from +0.1 in carbonate dominated catchments to >+2 ɛ-units in rivers draining predominantly silicate catchments. The silicate contributions estimated from our 40Ca results are in line with major element budgets when considering small catchments but largely exceeds

  5. 40K-40Ca and 87Rb-86Sr Dating by SIMS: The Double-Plus Advantage

    NASA Astrophysics Data System (ADS)

    Harrison, T. M.; McKeegan, K. D.; Schmitt, A. K.

    2009-12-01

    The decay of 40K to 40Ar forms the basis of the potassium-argon dating method, although only one out of every 10 parent atoms decays to daughter 40Ar. The other 90% decay to 40Ca giving, in principle, the 40K-40Ca decay system great potential for dating samples with high K/Ca. This method, however, has not been utilized as an ion-microprobe-based geochronometer, largely because these isotopes require a very high mass resolving power (MRP) of ~25k for full separation. We found that limiting secondary ion transmission in our ims1270 ion microprobe to ~20% permits sufficient separation of 40K from 40Ca (MRP≈ 20k) to permit isotope ratio analysis, albeit with 40Ca+ on the shoulder of the more intense 40K+ peak. A pegmatitic muscovite from Jack Hills (K-Ca age = 2.54 Ga; Fletcher et al., Chem. Geol. 138, 289) yields ~104 cps of both 40K+ and 40Ca+ with a 15 μm primary spot size and O- beam current of 10 nA. The 40Ca+ signal is >90% radiogenic and reflects a “common” Ca content of ≤ 100 ppm. However, application of the relative sensitivity factor (RSF) calculated from the Jack Hills muscovite to unknowns yields relatively high age dispersion, perhaps related to the incompletely separated mass interferences. Theorizing that the noble gas electronic structure of K+ would likely resist further electron loss, we investigated an alternative approach involving analysis of Ca++/K++. The double-plus method provides an important advantage in that K++ species are suppressed by a factor of ~103 relative to K+, thereby effectively removing 40K++ from the spectrum at m/e≈ 20 and leaving 40Ca++ free from any significant interferences at an MRP≈ 4k. Measurement of the much more abundant 39K++ then permits 40Ca++/40K++ to be calculated from the known 39K/40K ratio. We applied this approach to Precambrian muscovite samples obtaining ages similar to, but generally younger than, their associated 40Ar/39Ar ages. This could reflect a minor matrix effect or a lower intrinsic

  6. Estimating adipose tissue in the chest wall using ultrasonic and alternate /sup 40/K and biometric measurements

    SciTech Connect

    Anderson, A.L.; Campbell, G.W.

    1982-01-22

    The percentage of adipose (fat) tissue in the chest wall must be known to accurately measure Pu in the human lung. Correction factors of 100% or more in x-ray detection efficiency are common. Methods using simple /sup 40/K and biometric measurement techniques were investigated to determine the adipose content in the human chest wall. These methods predict adipose content to within 15% of the absolute ultrasonic value. These new methods are discussed and compared with conventional ultrasonic measurement techniques. (ERB)

  7. Assessments of radioactivity concentration of natural radionuclides and radiological hazard indices in sediment samples from the East coast of Tamilnadu, India with statistical approach.

    PubMed

    Ravisankar, R; Chandramohan, J; Chandrasekaran, A; Prince Prakash Jebakumar, J; Vijayalakshmi, I; Vijayagopal, P; Venkatraman, B

    2015-08-15

    This paper reports on the distribution of three natural radionuclides (238)U, (232)Th and (40)K in coastal sediments from Pattipulam to Devanampattinam along the East coast of Tamilnadu to establish baseline data for future environmental monitoring. Sediment samples were collected by a Peterson grab samples from 10m water depth parallel to the shore line. Concentration of natural radionuclides were determined using a NaI(Tl) detector based γ-spectrometry. The mean activity concentration is ⩽2.21, 14.29 and 360.23Bqkg(-1) for (238)U, (232)Th and (40)K, respectively. The average activity of (232)Th, (238)U and (40)K is lower when compared to the world average value. Radiological hazard parameters were estimated based on the activity concentrations of (238)U, (232)Th and (40)K to find out any radiation hazard associated with the sediments. The radiological hazard parameters such as radium equivalent activity (Raeq), absorbed gamma dose rates in air (DR), the annual gonadal dose equivalent (AGDE), annual effective dose equivalent (AEDE), external hazard index (Hex) internal hazard index (Hin), activity utilization index (AUI) and excess lifetime cancer (ELCR) associated with the radionuclides were calculated and compared with internationally approved values and the recommended safety limits. Pearson correlation, principal component analysis (PCA) and hierarchical cluster analysis (HCA) have been applied in order to recognize and classify radiological parameters in sediments collected at 22 sites on East coast of Tamilnadu. The values of radiation hazard parameters were comparable to the world averages and below the recommended values. Therefore, coastal sediments do not to pose any significant radiological health risk to the people living in nearby areas along East coast of Tamilnadu. The data obtained in this study will serve as a baseline data in natural radionuclide concentration in sediments along the coastal East coast of Tamilnadu. PMID:26036177

  8. Abundances of Natural Radionuclides (40K, 238U, 232Th) in Hanford and Rifle Integrated Field Research Challenge Site Sediments and the Application to the Estimation of Grain Size Distributions

    NASA Astrophysics Data System (ADS)

    Draper, K.; Ward, A. L.; Yabusaki, S.; Murray, C. J.; Greenwood, J.

    2009-12-01

    The distribution and geometry of lithofacies impact groundwater flow and solute spreading but are difficult to characterize at the scale controlling transport. We hypothesize that differences in γ-ray activity resulting from the natural distribution of 40K, 238U, and 232Th (K, U, T) are due to hydraulic separation and sorting and can be used to infer grain-size distributions at the scale of borehole γ-ray logs. The objective of this study was to investigate the feasibility of using γ-ray spectra to detect differences in grain size distributions as a means of characterizing small-scale variations in flow and reactive transport properties. The γ-ray spectra of whole and fractionated sediments from the Hanford and Old Rifle IFRC sites were characterized along with their grain size distributions. In the Hanford sediments, the abundance of K, U, and T was strongly correlated with the extent of weathering and with mean grain size. Hanford clay showed concentrations of 4%, 5.5 ppm, and 6.5 ppm for K, U, and T respectively. An increase in geometric mean diameter from 0.02 mm (clay) to 45.25 mm (very coarse gravel) showed increases in concentrations of 70% for K, 76% for U, and 83% for T. Old Rifle sediments showed no correlation between grain size and K, but there was an 81% increase in U and a 73 % increase in T. Cross plots of Th/U and Th/K also show strong correlations with grain size. The enrichment of natural isotopes with decreasing grain size is likely due to the increase in specific surface area. Thus, borehole γ-ray spectra could have a much wider application in characterizing grain separation and sorting and ultimately flow and reactive transport properties.

  9. A Comparison of Barley Malt Amylolytic Enzyme Activities and Malt Sugar Concentrations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was conducted to test the hypothesis that barley malt alpha-amylase activity would correlate better with malt sugar concentrations than the activities of beta-amylase, or limit dextrinase. Seeds of four two-row and four six-row North American elite barley cultivars were steeped and germi...

  10. A Comparison of Barley Malt Amylolytic Enzyme Activities and Malt Sugar Concentrations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was conducted to test the hypothesis that barley malt alpha-amylase activity would correlate better with malt sugar concentrations than the activities of beta-amylase, or limit dextrinase. Seeds of four two-row and four six-row North American elite barley cultivars were steeped and germin...

  11. Alteration of natural (37)Ar activity concentration in the subsurface by gas transport and water infiltration.

    PubMed

    Guillon, Sophie; Sun, Yunwei; Purtschert, Roland; Raghoo, Lauren; Pili, Eric; Carrigan, Charles R

    2016-05-01

    High (37)Ar activity concentration in soil gas is proposed as a key evidence for the detection of underground nuclear explosion by the Comprehensive Nuclear Test-Ban Treaty. However, such a detection is challenged by the natural background of (37)Ar in the subsurface, mainly due to Ca activation by cosmic rays. A better understanding and improved capability to predict (37)Ar activity concentration in the subsurface and its spatial and temporal variability is thus required. A numerical model integrating (37)Ar production and transport in the subsurface is developed, including variable soil water content and water infiltration at the surface. A parameterized equation for (37)Ar production in the first 15 m below the surface is studied, taking into account the major production reactions and the moderation effect of soil water content. Using sensitivity analysis and uncertainty quantification, a realistic and comprehensive probability distribution of natural (37)Ar activity concentrations in soil gas is proposed, including the effects of water infiltration. Site location and soil composition are identified as the parameters allowing for a most effective reduction of the possible range of (37)Ar activity concentrations. The influence of soil water content on (37)Ar production is shown to be negligible to first order, while (37)Ar activity concentration in soil gas and its temporal variability appear to be strongly influenced by transient water infiltration events. These results will be used as a basis for practical CTBTO concepts of operation during an OSI. PMID:26939033

  12. Effects of CO sub 2 concentration on rubisco activity, amount, and photosynthesis in soybean leaves

    SciTech Connect

    Campbell, W.J.; Allen, L.H. Jr.; Bowes, G. )

    1988-12-01

    Growth at an elevated CO{sub 2} concentration resulted in an enhanced capacity for soybean (Glycine max L. Merr. cv Bragg) leaflet photosynthesis. Plants were grown from seed in outdoor controlled-environment chambers under natural solar irradiance. Photosynthetic rates, measured during the seed filling stage, were up to 150% greater with leaflets grown at 660 compared to 330 microliters of CO{sub 2} per liter when measured across a range of intercellular CO{sub 2} concentrations and irradiance. Soybean plants grown at elevated CO{sub 2} concentrations had heavier pod weights per plant, 44% heavier with 660 compared to 330 microliters of CO{sub 2} per liter grown plants, and also greater specific leaf weights. Ribulose 1,5-bisphosphate carboxylase/oxygenase (rubisco) activity showed no response (mean activity of 96 micromoles of CO{sub 2} per square meter per second expressed on a leaflet area basis) to short-term ({approximately}1 hour) exposures to a range of CO{sub 2} concentrations (110-880 microliters per liter), nor was a response of activity (mean activity of 1.01 micromoles of CO{sub 2} per minute per milligram of protein) to growth CO{sub 2} concentration (160-990 microliters per liter) observed. The amount of rubisco protein was constant, as growth CO{sub 2} concentration was varied, and averaged 55% of the total leaflet soluble protein. Although CO{sub 2} is required for activation of rubisco, results indicated that within the range of CO{sub 2} concentrations used (110-990 microliters per liter), rubisco activity in soybean leaflets, in the light, was not regulated by CO{sub 2}.

  13. Relationship between Salivary Alkaline Phosphatase Enzyme Activity and The Concentrations of Salivary Calcium and Phosphate Ions

    PubMed Central

    Jazaeri, Mina; Malekzadeh, Hosein; Abdolsamadi, Hamidreza; Rezaei-Soufi, Loghman; Samami, Mohammad

    2015-01-01

    Although salivary alkaline phosphatase (ALP) can balance deand remineralization processes of enamel, there is no evidence regarding its effects on the concentrations of calcium and phosphate in saliva. The present study aims to determine the relationship between salivary ALP activity and the concentrations of calcium and phosphate in saliva. In this cross-sectional study, we evaluated salivary markers in 120 males, ages 19 to 44 years. All participants provided 5 mL of unstimulated whole saliva and the level of enzyme activity as well as calcium and phosphate concentrations were measured using a colorimetric method. Data were gathered and analyzed by statistical package for social sciences (SPSS) 13.00 using Pearson correlation test. A p value of <0.05 was considered statistically significant. The mean age of participants in the present study was 32.95 ± 8.09 years. The mean pH of saliva was 6.65 ± 0.62. Salivary parameters included average ALP activity (5.04 ± 1.866 U/dL), calcium (4.77 ± 0.877 mg/dL) and phosphate (10.38 ± 2.301 mg/dL). Pearson correlation test showed no significant relationship between ALP activity and calcium and phosphate concentrations in saliva (p>0.05). According to the results of the present study, there was no significant relation between salivary ALP activity and calcium and phosphate concentrations in saliva. However, further research is highly recommended. PMID:25870846

  14. Relationship between Salivary Alkaline Phosphatase Enzyme Activity and The Concentrations of Salivary Calcium and Phosphate Ions.

    PubMed

    Jazaeri, Mina; Malekzadeh, Hosein; Abdolsamadi, Hamidreza; Rezaei-Soufi, Loghman; Samami, Mohammad

    2015-01-01

    Although salivary alkaline phosphatase (ALP) can balance deand remineralization processes of enamel, there is no evidence regarding its effects on the concentrations of calcium and phosphate in saliva. The present study aims to determine the relationship between salivary ALP activity and the concentrations of calcium and phosphate in saliva. In this cross-sectional study, we evaluated salivary markers in 120 males, ages 19 to 44 years. All participants provided 5 mL of unstimulated whole saliva and the level of enzyme activity as well as calcium and phosphate concentrations were measured using a colorimetric method. Data were gathered and analyzed by statistical package for social sciences (SPSS) 13.00 using Pearson correlation test. A p value of <0.05 was considered statistically significant. The mean age of participants in the present study was 32.95 ± 8.09 years. The mean pH of saliva was 6.65 ± 0.62. Salivary parameters included average ALP activity (5.04 ± 1.866 U/dL), calcium (4.77 ± 0.877 mg/dL) and phosphate (10.38 ± 2.301 mg/dL). Pearson correlation test showed no significant relationship between ALP activity and calcium and phosphate concentrations in saliva (p>0.05). According to the results of the present study, there was no significant relation between salivary ALP activity and calcium and phosphate concentrations in saliva. However, further research is highly recommended. PMID:25870846

  15. Contraceptive steroid concentrations in women with early active schistosomiasis: lack of effect of antischistosomal drugs.

    PubMed

    el-Raghy, I; Back, D J; Osman, F; Orme, M L; Fathalla, M

    1986-04-01

    Plasma concentrations of the oral contraceptive steroids (OCS) ethinyloestradiol (EE2) and levonorgestrel (LNG) have been determined in women with early active schistosomiasis and compared to those obtained in healthy volunteers. Steroid concentrations following a single dose of Ovral (500 micrograms LNG, 50 micrograms EE2) or during a multiple dose regimen were unaffected by the disease. There was no significant effect of the antischistosomal drugs praziquantel (40 mg X kg-1) or metrifonate (10 mg X kg-1 X 3 at 2-week intervals) on plasma steroid concentrations. In regular users of OCS, significantly higher concentrations of LNG were observed than in women who received only a single dose. We conclude that there is no pharmacokinetic reason for withholding OCS from patients with early active schistosomiasis who are also receiving either praziquantel or metrifonate. PMID:3089682

  16. Telomerase activity concentrates in the mitotically active segments of human hair follicles.

    PubMed

    Ramirez, R D; Wright, W E; Shay, J W; Taylor, R S

    1997-01-01

    Telomerase is a ribonucleoprotein enzyme capable of adding hexanucleotide repeats onto the ends of linear chromosomal DNA. Whereas normal somatic cells with a limited replicative capacity fail to express telomerase activity, most immortal eukaryotic cells do. Cells of renewal tissues (e.g., skin, intestine, blood) require an extensive proliferative capacity. Some cells in such renewal tissues also express telomerase activity, most likely to prevent rapid erosion of their telomeres during cell proliferation. In this study, we measured the levels of telomerase activity in dissected compartments of the human hair follicle: hair shaft, gland-containing fragment, upper intermediate fragment (where it is thought undifferentiated stem cells reside), lower intermediate fragment, and in the bulb-containing fragment (an area with high mitotic activity containing a more differentiated pool of keratinocytes). In anagen follicles, high levels of telomerase activity were found almost exclusively in the bulb-containing fragment of the follicles, with low levels of telomerase in the bulge area (intermediate fragments) and gland-containing fragment. In comparison, catagen follicles had low levels of telomerase activity in the bulb-containing fragments as well as in other compartments. Such observations indicate that, in anagen hair follicles, the fragments containing cells actively dividing (e.g., transient amplifying cells) express telomerase activity, whereas fragments containing cells with low mitotic activity, for example, quiescent stem cells, express low levels of telomerase activity. PMID:8980299

  17. Blood selenium concentrations and enzyme activities related to glutathione metabolism in wild emperor geese

    USGS Publications Warehouse

    Franson, J.C.; Hoffman, D.J.; Schmutz, J.A.

    2002-01-01

    In 1998, we collected blood samples from 63 emperor geese (Chen canagica) on their breeding grounds on the Yukon-Kuskokwim Delta (YKD) in western Alaska, USA. We studied the relationship between selenium concentrations in whole blood and the activities of glutathione peroxidase and glutathione reductase in plasma. Experimental studies have shown that plasma activities of these enzymes are useful biomarkers of selenium-induced oxidative stress, but little information is available on their relationship to selenium in the blood of wild birds. Adult female emperor geese incubating their eggs in mid-June had a higher mean concentration of selenium in their blood and a greater activity of glutathione peroxidase in their plasma than adult geese or goslings that were sampled during the adult flight feathera??molting period in late July and early August. Glutathione peroxidase activity was positively correlated with the concentration of selenium in the blood of emperor geese, and the rate of increase relative to selenium was greater in goslings than in adults. The activity of glutathione reductase was greatest in the plasma of goslings and was greater in molting adults than incubating females but was not significantly correlated with selenium in the blood of adults or goslings. Incubating female emperor geese had high selenium concentrations in their blood, accompanied by increased glutathione peroxidase activity consistent with early oxidative stress. These findings indicate that further study of the effects of selenium exposure, particularly on reproductive success, is warranted in this species.

  18. Blood selenium concentrations and enzyme activities related to glutathione metabolism in wild emperor geese

    USGS Publications Warehouse

    Franson, J.C.; Hoffman, D.J.; Schmutz, J.A.

    2002-01-01

    In 1998, we collected blood samples from 63 emperor geese (Chen canagica) on their breeding grounds on the Yukon-Kuskokwim Delta (YKD) in western Alaska, USA. We studied the relationship between selenium concentrations in whole blood and the activities of glutathione peroxidase and glutathione reductase in plasma. Experimental studies have shown that plasma activities of these enzymes are useful biomarkers of selenium-induced oxidative stress, but little information is available on their relationship to selenium in the blood of wild birds. Adult female emperor geese incubating their eggs in mid-June had a higher mean concentration of selenium in their blood and a greater activity of glutathione peroxidase in their plasma than adult geese or goslings that were sampled during the adult flight feathermolting period in late July and early August. Glutathione peroxidase activity was positively correlated with the concentration of selenium in the blood of emperor geese, and the rate of increase relative to selenium was greater in goslings than in adults. The activity of glutathione reductase was greatest in the plasma of goslings and was greater in molting adults than incubating females but was not significantly correlated with selenium in the blood of adults or goslings. Incubating female emperor geese had high selenium concentrations in their blood, accompanied by increased glutathione peroxidase activity consistent with early oxidative stress. These findings indicate that further study of the effects of selenium exposure, particularly on reproductive success, is warranted in this species.

  19. Investigation of radioactivity concentration in spent technetium generators

    NASA Astrophysics Data System (ADS)

    Idriss, Hajo; Salih, Isam; Alaamer, Abdulaziz S.; Eisa, M. H.; Sam, A. K.

    2014-04-01

    This study was carried out to survey and measure radioactivity concentration and estimate radiation dose level at the surface of spent technetium generator columns for the safe final disposal of radioactive waste. High resolution γ-spectrometry with the aid of handheld radiation survey meters has been used. The radioactivity measurements has shown that 238U, 40K and 137Cs were only measurable in one sample whereas 125Sb was found in 14 samples out of total of 20 samples with an activity concentration which ranged from 21 to 7404 with an average value of 1095 Bq/kg. The activity concentration of 125Sb is highly variable indicating that the spent 99mTc generator columns are of different origin. This investigation highlighted the importance of radiation monitoring of spent technetium generators in the country in order to protect workers, and the public from the dangers posed by radioactive waste.

  20. Intramuscular pressure and torque during isometric, concentric and eccentric muscular activity

    NASA Technical Reports Server (NTRS)

    Styf, J.; Ballard, R.; Aratow, M.; Crenshaw, A.; Watenpaugh, D.; Hargens, A. R.

    1995-01-01

    Intramuscular pressures, electromyography (EMG) and torque generation during isometric, concentric and eccentric maximal isokinetic muscle activity were recorded in 10 healthy volunteers. Pressure and EMG activity were continuously and simultaneously measured side by side in the tibialis anterior and soleus muscles. Ankle joint torque and position were monitored continuously by an isokinetic dynamometer during plantar flexion and dorsiflexion of the foot. The increased force generation during eccentric muscular activity, compared with other muscular activity, was not accompanied by higher intramuscular pressure. Thus, this study demonstrated that eccentric muscular activity generated higher torque values for each increment of intramuscular pressure. Intramuscular pressures during antagonistic co-activation were significantly higher in the tibilis anterior muscle (42-46% of maximal agonistic activity) compared with the soleus muscle (12-29% of maximal agonistic activity) and was largely due to active recruitment of muscle fibers. In summary, eccentric muscular activity creates higher torque values with no additional increase of the intramuscular pressure compared with concentric and isometric muscular activity.

  1. PCB concentrations and activity of sea lamprey Petromyzon marinus vary by sex

    USGS Publications Warehouse

    Madenjian, Charles P.; Johnson, Nicholas S.; Binder, Thomas R.; Rediske, Richard R.; O'Keefe, James P.

    2013-01-01

    We determined the polychlorinated biphenyl (PCB) concentrations of 40 male and 40 female adult sea lampreys Petromyzon marinus captured in the Cheboygan River, a tributary to Lake Huron, during May 2011. In addition, we performed a laboratory experiment using passive integrated transponder tags to determine whether male adult sea lampreys were more active than female adult sea lampreys. Sex had a significant effect on PCB concentration, and PCB concentration at a given level of sea lamprey condition was approximately 25 % greater in males than in females. Adjusting for the difference in condition between the sexes, males averaged a 17 % greater PCB concentration compared with females. Results from the laboratory experiment indicated that males were significantly more active than females. The observed sex difference in PCB concentrations was not due to female sea lampreys releasing eggs at spawning because the sea lamprey is semelparous, and we caught the sea lampreys before spawning. Rather, we attributed the sex difference in PCB concentrations to a greater rate of energy expenditure in males compared with females. We proposed that this greater rate of energy expenditure was likely due to greater activity. Our laboratory experiment results supported this hypothesis. A greater resting metabolic rate may also have contributed to a greater rate of energy expenditure. Our findings should eventually be applicable toward improving control of sea lamprey, a pest responsible for considerable damage to fisheries in lakes where it is not native.

  2. Preparation of factor VII concentrate using CNBr-activated Sepharose 4B immunoaffinity chromatography

    PubMed Central

    Mousavi Hosseini, Kamran; Nasiri, Saleh

    2015-01-01

    Background: Factor VII concentrates are used in patients with congenital or acquired factor VII deficiency or treatment of hemophilia patients with inhibitors. In this research, immunoaffinity chromatography was used to purify factor VII from prothrombin complex (Prothrombin- Proconvertin-Stuart Factor-Antihemophilic Factor B or PPSB) which contains coagulation factors II, VII, IX and X. The aim of this study was to improve purity, safety and tolerability as a highly purified factor VII concentrate. Methods: PPSB was prepared using DEAE-Sephadex and was used as the starting material for purification of coagulation factor VII. Prothrombin complex was treated by solvent/detergent at 24°C for 6 h with constant stirring. The mixture of PPSB in the PBS buffer was filtered and then chromatographed using CNBr-activated Sepharose 4B coupled with specific antibody. Factors II, IX, VII, X and VIIa were assayed on the fractions. Fractions of 48-50 were pooled and lyophilized as a factor VII concentrate. Agarose gel electrophoresis was performed and Tween 80 was measured in the factor VII concentrate. Results: Specific activity of factor VII concentrate increased from 0.16 to 55.6 with a purificationfold of 347.5 and the amount of activated factor VII (FVIIa) was found higher than PPSB (4.4-fold). Results of electrophoresis on agarose gel indicated higher purity of Factor VII compared to PPSB; these finding revealed that factor VII migrated as alpha-2 proteins. In order to improve viral safety, solvent-detergent treatment was applied prior to further purification and nearly complete elimination of tween 80 (2 μg/ml). Conclusion: It was concluded that immuonoaffinity chromatography using CNBr-activated Sepharose 4B can be a suitable choice for large-scale production of factor VII concentrate with higher purity, safety and activated factor VII. PMID:26034723

  3. Antioxidant activities of polysaccharides obtained from Chlorella pyrenoidosa via different ethanol concentrations.

    PubMed

    Chen, Yi-Xuan; Liu, Xiao-Yan; Xiao, Zheng; Huang, Yi-Fan; Liu, Bin

    2016-10-01

    An ultrasonic-assisted extraction of Chlorella pyrenoidosa polysaccharides (CPP) was carried out using different concentrations of ethanol for precipitation, and named as CPP60, CPP70 and CPP85, respectively. The monosaccharide composition of each polysaccharide (CPP) was determined using gas chromatography (GC) and the antioxidant activity of each was investigated via the reducing power and scavenging activity of hydroxyl radicals, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals and superoxide anion radicals, respectively. All of the polysaccharides examined possessed antioxidant activity in vitro. CPP70 exhibited stronger scavenging activity against superoxide, DPPH and hydroxyl radicals, when compared with CPP60 and CPP85. This suggests that polysaccharides from C. pyrenoidosa precipitated by a final ethanol concentration of 70%, have the potential to be developed as natural antioxidants for use in food and pharmaceuticals. PMID:27235730

  4. Relationship between Physical Activity and Plasma Fibrinogen Concentrations in Adults without Chronic Diseases

    PubMed Central

    Gomez-Marcos, Manuel A.; Recio-Rodríguez, José I.; Patino-Alonso, Maria C.; Martinez-Vizcaino, Vicente; Martin-Borras, Carme; de-la-Cal-dela-Fuente, Aventina; Sauras-Llera, Ines; Sanchez-Perez, Alvaro; Agudo-Conde, Cristina; García-Ortiz, Luis

    2014-01-01

    Objective To analyze the relationship between regular physical activity, as assessed by accelerometer and 7-day physical activity recall (PAR), and plasma fibrinogen concentrations. Methods A cross-sectional study in a previously established cohort of healthy subjects was performed. This study analyzed 1284 subjects who were included in the EVIDENT study (mean age 55.0±13.6 years; 60.90% women). Fibrinogen concentrations were measured in blood plasma. Physical activity was assessed with a 7-day PAR (metabolic equivalents (METs)/hour/week) and GT3X ActiGraph accelerometer (counts/minute) for 7 days. Results Physical exercise, which was evaluated with both an accelerometer (Median: 237.28 counts/minute) and 7-day PAR (Median: 8 METs/hour/week). Physical activity was negatively correlated with plasma fibrinogen concentrations, which was evaluated by counts/min (r = −0.100; p<0.001) and METs/hour/week (r = −0.162; p<0.001). In a multiple linear regression analysis, fibrinogen concentrations of the subjects who performed more physical activity (third tertile of count/minute and METs/hour/week) respect to subjects who performed less (first tertile), maintained statistical significance after adjustments for age and others confounders (β = −0.03; p = 0.046 and β = −0.06; p<0.001, respectively). Conclusions Physical activity, as assessed by accelerometer and 7-day PAR, was negatively associated with plasma fibrinogen concentrations. This relation is maintained in subjects who performed more exercise even after adjusting for age and other confounders. PMID:24498413

  5. The relationship between infliximab concentrations, antibodies to infliximab and disease activity in Crohn's disease

    PubMed Central

    Vande Casteele, Niels; Khanna, Reena; Levesque, Barrett G; Stitt, Larry; Zou, G Y; Singh, Sharat; Lockton, Steve; Hauenstein, Scott; Ohrmund, Linda; Greenberg, Gordon R; Rutgeerts, Paul J; Gils, Ann; Sandborn, William J; Vermeire, Séverine; Feagan, Brian G

    2015-01-01

    Objective Although low infliximab trough concentrations and antibodies to infliximab (ATI) are associated with poor outcomes in patients with Crohn's disease (CD), the clinical relevance of ATI in patients with adequate infliximab concentrations is uncertain. We evaluated this question using an assay sensitive for identification of ATI in the presence of infliximab. Design In an observational study, 1487 trough serum samples from 483 patients with CD who participated in four clinical studies of maintenance infliximab therapy were analysed using a fluid phase mobility shift assay. Infliximab and ATI concentrations most discriminant for remission, defined as a C-reactive protein concentration of ≤5 mg/L, were determined by receiver operating characteristic curves. A multivariable regression model evaluated these factors as independent predictors of remission. Results Based upon analysis of 1487 samples, 77.1% of patients had detectable and 22.9% had undetectable infliximab concentrations, of which 9.5% and 71.8%, respectively, were positive for ATI. An infliximab concentration of >2.79 μg/mL (area under the curve (AUC)=0.681; 95% CI 0.632 to 0.731) and ATI concentration of <3.15 U/mL (AUC=0.632; 95% CI 0.589 to 0.676) were associated with remission. Multivariable analysis showed that concentrations of both infliximab trough (OR 1.8; 95% CI 1.3 to 2.5; p<0.001) and ATI (OR 0.57; 95% CI 0.39 to 0.81; p=0.002) were independent predictors of remission. Conclusions The development of ATI increases the probability of active disease even at low concentrations and in the presence of a therapeutic concentration of drug during infliximab maintenance therapy. Evaluation of strategies to prevent ATI formation, including therapeutic drug monitoring with selective infliximab dose intensification, is needed. PMID:25336114

  6. Coding Odorant Concentration Through Activation Timing Between the Medial and Lateral Olfactory Bulb

    PubMed Central

    Zhou, Zhishang; Belluscio, Leonardo

    2012-01-01

    SUMMARY In mammals, each olfactory bulb (OB) contains a pair of mirror-symmetric glomerular maps organized to reflect odorant receptor identity. The functional implication of maintaining these symmetric medial-lateral maps within each OB remains unclear. Here, using in vivo multi-electrode recordings to simultaneously detect odorant-induced activity across the entire OB, we reveal a timing difference in the odorant-evoked onset latencies between the medial and lateral halves. Interestingly, the latencies in the medial and lateral OB decreased at different rates as odorant concentration increased, causing the timing difference between them to also diminish. As a result, output neurons in the medial and lateral OB fired with greater synchrony at higher odorant concentrations. Thus, we propose that temporal differences in activity between the medial and lateral OB can dynamically code odorant concentration, which is subsequently decoded in the olfactory cortex through the integration of synchronous action potentials. PMID:23168258

  7. Low Ozone Concentrations Stimulate Cytoskeletal Organization, Mitochondrial Activity and Nuclear Transcription

    PubMed Central

    Costanzo, M.; Cisterna, B.; Vella, A.; Cestari, T.; Covi, V.; Tabaracci, G.; Malatesta, M.

    2015-01-01

    Ozone therapy is a modestly invasive procedure based on the regeneration capabilities of low ozone concentrations and used in medicine as an alternative/adjuvant treatment for different diseases. However, the cellular mechanisms accounting for the positive effects of mild ozonization are still largely unexplored. To this aim, in the present study the effects of low ozone concentrations (1 to 20 µg O3/mL O2) on structural and functional cell features have been investigated in vitro by using morphological, morphometrical, cytochemical and immunocytochemical techniques at bright field, fluorescence and transmission electron microscopy. Cells exposed to pure O2 or air served as controls. The results demonstrated that the effects of ozone administration are dependent on gas concentration, and the cytoskeletal organization, mitochondrial activity and nuclear transcription may be differently affected. This suggests that, to ensure effective and permanent metabolic cell activation, ozone treatments should take into account the cytological and cytokinetic features of the different tissues. PMID:26150162

  8. Low ozone concentrations stimulate cytoskeletal organization, mitochondrial activity and nuclear transcription.

    PubMed

    Costanzo, M; Cisterna, B; Vella, A; Cestari, T; Covi, V; Tabaracci, G; Malatesta, M

    2015-01-01

    Ozone therapy is a modestly invasive procedure based on the regeneration capabilities of low ozone concentrations and used in medicine as an alternative/adjuvant treatment for different diseases. However, the cellular mechanisms accounting for the positive effects of mild ozonization are still largely unexplored. To this aim, in the present study the effects of low ozone concentrations (1 to 20 µg O3/mL O2) on structural and functional cell features have been investigated in vitro by using morphological, morphometrical, cytochemical and immunocytochemical techniques at bright field, fluorescence and transmission electron microscopy. Cells exposed to pure O2 or air served as controls. The results demonstrated that the effects of ozoneadministration are dependent on gas concentration, and the cytoskeletal organization, mitochondrial activity and nuclear transcription may be differently affected. This suggests that, to ensure effective and permanent metabolic cell activation, ozone treatments should take into account the cytological and cytokinetic features of the different tissues. PMID:26150162

  9. Spatial variability of dissolved phosphorous concentrations and alkaline phosphatase activity in the East China Sea

    NASA Astrophysics Data System (ADS)

    Liu, H.; Chang, J.; Ho, T.; Gong, G.

    2010-12-01

    The concentrations of dissolved inorganic phosphorus (DIP) and alkaline phosphatase activity (APA) have been determined at about 25 sampling stations in the East China Sea since 2003. The stations are mainly distributed from the Changjiang river mouth to northern Taiwan and east to the shelf break. In addition to the Changjiang discharge, we have found a specific nutrient source around a coastal site (122° 2’30’’ E, 28° 40’ N). Elevated DIP and nitrate concentrations have been constantly observed around the sampling station for 8 years, where the surface DIP concentrations are generally around 0.3 µM. The nutrient source may either originate from ground water discharge or coastal upwelling, where lower temperature has been observed in the water column around the station. In general, APA has been negatively correlated with DIP concentrations in the studies sites, with lowest APA around the high DIP station and the Changjiang river mouth.

  10. EFFECT OF PHOTOPERIOD ON PLATELET-ACTIVATING FACTOR CONCENTRATION IN BOAR SPERMATOZOA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Platelet-activating factor (PAF, 1-0-alkyl-2-acetyl-sn-glycero-3-phosphocholine) is an important phospholipid mediator shown to be involved in fertilization. We recently reported that boars with a 70% or higher fertility history have a higher concentration of PAF in their spermatozoa. In addition,...

  11. SELENIUM CONCENTRATIONS AND GLULATHIONE PEROXIDASE ACTIVITIES IN A POPULATION EXPOSED TO SELENIUM VIA DRINKING WATER

    EPA Science Inventory

    Selenium concentrations in blood, urine, hair, and tap water were determined in samples obtained from individuals exposed to varying amounts of the element via water from home wells. Glutathione peroxidase activities were also determined on the blood samples. Correlations of bloo...

  12. 13 CFR 120.828 - Minimum level of 504 loan activity and restrictions on portfolio concentrations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Minimum level of 504 loan activity and restrictions on portfolio concentrations. 120.828 Section 120.828 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Requirements for Cdc Certification and Operation §...

  13. Differential effects of mental concentration and acute psychosocial stress on cervical muscle activity and posture.

    PubMed

    Shahidi, Bahar; Haight, Ashley; Maluf, Katrina

    2013-10-01

    Physical and psychosocial stressors in the workplace have been independently associated with the development of neck pain, yet interactions among these risk factors remain unclear. The purpose of this study was to compare the effects of mentally challenging computer work performed with and without exposure to a psychosocial stressor on cervical muscle activity and posture. Changes in cervical posture and electromyography of upper trapezius, cervical extensor, and sternocleidomastoid muscles were compared between a resting seated posture at baseline, a low stress condition with mental concentration, and a high stress condition with mental concentration and psychosocial stress in sixty healthy office workers. Forward head posture significantly increased with mental concentration compared to baseline, but did not change with further introduction of the stressor. Muscle activity significantly increased from the low stress to high stress condition for both the dominant and non-dominant upper trapezius, with no corresponding change in activity of the cervical extensors or flexors between stress conditions. These findings suggest that upper trapezius muscles are selectively activated by psychosocial stress independent of changes in concentration or posture, which may have implications for the prevention of stress-related trapezius myalgia in the workplace. PMID:23800438

  14. Differential effects of mental concentration and acute psychosocial stress on cervical muscle activity and posture

    PubMed Central

    Shahidi, Bahar; Haight, Ashley; Maluf, Katrina

    2013-01-01

    Physical and psychosocial stressors in the workplace have been independently associated with the development of neck pain, yet interactions among these risk factors remain unclear. The purpose of this study was to compare the effects of mentally challenging computer work performed with and without exposure to a psychosocial stressor on cervical muscle activity and posture. Changes in cervical posture and electromyography of upper trapezius, cervical extensor, and sternocleidomastoid muscles were compared between a resting seated posture at baseline, a low stress condition with mental concentration, and a high stress condition with mental concentration and psychosocial stress in sixty healthy office workers. Forward head posture significantly increased with mental concentration compared to baseline, but did not change with further introduction of the stressor. Muscle activity significantly increased from the low stress to high stress condition for both the dominant and non-dominant upper trapezius, with no corresponding change in activity of the cervical extensors or flexors between stress conditions. These findings suggest that upper trapezius muscles are selectively activated by psychosocial stress independent of changes in concentration or posture, which may have implications for the prevention of stress-related trapezius myalgia in the workplace. PMID:23800438

  15. Combined effects of water temperature and copper ion concentration on catalase activity in Crassostrea ariakensis

    NASA Astrophysics Data System (ADS)

    Wang, Hui; Yang, Hongshuai; Liu, Jiahui; Li, Yanhong; Liu, Zhigang

    2015-07-01

    A central composite experimental design and response surface method were used to investigate the combined effects of water temperature (18-34°C) and copper ion concentration (0.1-1.5 mg/L) on the catalase (CAT) activity in the digestive gland of Crassostrea ariakensis. The results showed that the linear effects of temperature were significant ( P<0.01), the quadratic effects of temperature were significant ( P<0.05), the linear effects of copper ion concentration were not significant ( P>0.05), and the quadratic effects of copper ion concentration were significant ( P<0.05). Additionally, the synergistic effects of temperature and copper ion concentration were not significant ( P>0.05), and the effect of temperature was greater than that of copper ion concentration. A model equation of CAT enzyme activity in the digestive gland of C. ariakensis toward the two factors of interest was established, with R 2, Adj. R 2 and Pred. R 2 values as high as 0.943 7, 0.887 3 and 0.838 5, respectively. These findings suggested that the goodness of fit to experimental data and predictive capability of the model were satisfactory, and could be practically applied for prediction under the conditions of the study. Overall, the results suggest that the simultaneous variation of temperature and copper ion concentration alters the activity of the antioxidant enzyme CAT by modulating active oxygen species metabolism, which may be utilized as a biomarker to detect the effects of copper pollution.

  16. Ovicidal activity of different concentrations of Pochonia chlamydosporia chlamydospores on Taenia taeniaeformis eggs.

    PubMed

    Braga, F R; Silva, A R; Carvalho, R O; Araújo, J V; Pinto, P S A

    2011-03-01

    Three concentrations of chlamydospores of the nematophagous fungus Pochonia chlamydosporia (1000, 10,000 and 20,000 per Petri dish) were evaluated in vitro on Taenia taeniaeformis eggs. Chlamydospores at each concentration were cultured in two different media: 2% water-agar (2%WA) and 2% corn-meal-agar (2%CMA). Taenia taeniaeformis eggs were plated in each chlamydospore concentration in 2%WA and 2%CMA (treated groups) and without fungus (control group). Eggs were removed from each Petri dish at intervals of 7, 14 and 21 days and classified according to ovicidal activity (type 1, type 2 and type 3 effects). Plates containing 2%CMA showed the highest percentages for type 3 effect (81.3%) on the 21st day of observation. A difference (P < 0.01) between the media 2%WA and 2%CMA for type 1 effect was observed only at a concentration of 1000 chlamydospores on the 7th day. There were differences (P < 0.01) between 2%WA and 2%CMA on the 14th and 21st days, at the concentration of 20,000 chlamydospores, for type 1 and type 3 effects. Regression curves for type 3 effect in 2%WA and 2%CMA at the tested concentrations showed higher ovicidal activity with increasing chlamydospore concentrations. Results indicate that, at concentrations of 1000, 10,000 and 20,000 per Petri dish, chlamydospores of P. chlamydosporia effectively destroyed T. taeniaeformis eggs and can be considered a potential biological control agent for this cestode. PMID:20338078

  17. Estimating ROI activity concentration with photon-processing and photon-counting SPECT imaging systems

    NASA Astrophysics Data System (ADS)

    Jha, Abhinav K.; Frey, Eric C.

    2015-03-01

    Recently a new class of imaging systems, referred to as photon-processing (PP) systems, are being developed that uses real-time maximum-likelihood (ML) methods to estimate multiple attributes per detected photon and store these attributes in a list format. PP systems could have a number of potential advantages compared to systems that bin photons based on attributes such as energy, projection angle, and position, referred to as photon-counting (PC) systems. For example, PP systems do not suffer from binning-related information loss and provide the potential to extract information from attributes such as energy deposited by the detected photon. To quantify the effects of this advantage on task performance, objective evaluation studies are required. We performed this study in the context of quantitative 2-dimensional single-photon emission computed tomography (SPECT) imaging with the end task of estimating the mean activity concentration within a region of interest (ROI). We first theoretically outline the effect of null space on estimating the mean activity concentration, and argue that due to this effect, PP systems could have better estimation performance compared to PC systems with noise-free data. To evaluate the performance of PP and PC systems with noisy data, we developed a singular value decomposition (SVD)-based analytic method to estimate the activity concentration from PP systems. Using simulations, we studied the accuracy and precision of this technique in estimating the activity concentration. We used this framework to objectively compare PP and PC systems on the activity concentration estimation task. We investigated the effects of varying the size of the ROI and varying the number of bins for the attribute corresponding to the angular orientation of the detector in a continuously rotating SPECT system. The results indicate that in several cases, PP systems offer improved estimation performance compared to PC systems.

  18. Intracellular activity of clinical concentrations of phenothiazines including thioridiazine against phagocytosed Staphylococcus aureus.

    PubMed

    Ordway, Diane; Viveiros, Miguel; Leandro, Clara; Arroz, Maria Jorge; Amaral, Leonard

    2002-07-01

    The effect of thioridazine (TZ) was studied on the killing activity of human peripheral blood monocyte derived macrophages (HPBMDM) and of human macrophage cell line THP-1 at extracellular concentrations below those achievable clinically. These macrophages have nominal killing activity against bacteria and therefore, would not influence any activity that the compounds may have against intracellular localised Staphylococcus aureus. The results indicated that whereas TZ has an in vitro minimum inhibitory concentration (MIC) against the strains of S. aureus of 18, 0.1 mg/l of TZ in the medium completely inhibits the growth of S. aureus that has been phagocytosed by macrophages. The latter concentration was non-toxic to macrophages, did not cause cellular expression of activation marker CD69 nor induction of CD3+ T cell production of IFN-gamma, but blocked cellular proliferation and down-regulated the production of T cell-derived cytokines (IFN-gamma, IL-5). These results suggest that TZ induces intracellular bactericidal activities independent of the capacity to generate Type 1 responses against S. aureus. PMID:12127709

  19. Monte Carlo simulation of {sup 40}K in-vivo body-count spectra for different body shapes

    SciTech Connect

    Schillaci, M.E.; Brown, T.H.

    1996-06-01

    Over the course of several years of measuring in-vivo spectra (whole-body counts) in search of transuranic radionuclides, it has been observed that, relative to the count rate in a region around 80 keV (defined as region 3), large persons have relatively higher count rates than thin persons at around 60 keV (region 2, where an {sup 241}Am line is expected), and relatively lower count rates at around 17 keV (region 1, where both {sup 239}Pu and {sup 241}Am lines are expected). The observed data can be understood in terms of relative amounts of scattering and absorption of the 1.461-MeV photon from {sup 40}K, which occurs naturally in the human body. For larger persons, increased scattering causes the Compton peak to shift to lower energies, thereby increasing the count rate in region 2 relative to region 3. Also, because of increased absorption of very low energy photons, the count rate in region 1 decreases relative to region 3. To test this hypothesis, we compute the Spectrum of photons emerging from cylindrical human phantoms of various dimensions, assuming a variety of distributions of {sup 40}K within the phantom. The calculations are carried out using the Monte Carlo transport code MCNP. The results of these calculations qualitatively agree with the observations and support our hypothesis.

  20. Recovery of Protective Activity in Rabies Virus Vaccines Concentrated and Purified by Four Different Methods

    PubMed Central

    Aasletad, H. G.; Wiktor, T. J.

    1972-01-01

    Rabies vaccines concentrated by ultrafiltration, zinc acetate precipitation, ammonium sulfate precipitation, or aluminum phosphate gel adsorption were compared with respect to recovery of protective activity and purity, as measured by protective activity per mg of protein. Vaccine obtained by ammonium sulfate precipitation had a better recovery rate and a higher purity than those prepared by the other methods. Potent vaccines were also obtained by the zinc acetate precipitation and aluminum phosphate gel adsorption methods, whereas ultrafiltration was the least satisfactory method from the standpoint of vaccine purity. Chromatography of virus concentrated by ultrafiltration on a cellulose ion exchange column reduced the level of nonviral proteins. The protective activity data obtained for the vaccines examined in these experiments were found to correlate with the vaccine's complement fixation titer per mg of protein. PMID:5057372

  1. Pharmacokinetics, tissue distribution and excretion of 40kDa PEG and PEGylated rFVIII (N8-GP) in rats.

    PubMed

    Bjørnsdottir, Inga; Sternebring, Ola; Kappers, Wendela A; Selvig, Helle; Kornø, Hanne T; Kristensen, Jesper B; Bagger, Morten A

    2016-05-25

    The biologic fate of the [(3)H]PEG-moiety incorporated into N8-GP was evaluated based on single i.v. bolus doses to rats. Furthermore, the 40kDa [(3)H]PEG-moiety was given separately to rats by single i.v. bolus doses, to investigate if the pharmacokinetics were dose-dependent. For both compounds, plasma pharmacokinetics, distribution and excretion pathways were investigated, based on total radioactivity measurements ([(3)H]N8-GP: 0.17-4.1mg/kg;~1300-30,000U/kg, PEG load of ~0.03-0.7mg/kg); ([(3)H]PEG: 0.6, 1, 12, 100 and 200mg/kg). The plasma concentration of the intact N8-GP conjugate was also measured by ELISA. After single i.v. administration to rats, both [(3)H]N8-GP and [(3)H]PEG were shown to be widely distributed, mainly in highly vascularized tissues, with the lowest levels of radioactivity found in the CNS. Though a slow elimination of radioactivity was observed over the 12-week study period, approximately half of the radioactive dose of either compound was removed from the body 1week post-dose. The radioactivity was eliminated mainly via the kidney into urine but also via the liver into feces, with a larger fraction found in the feces for [(3)H]N8-GP. Elimination of the 40kDa PEG-moiety was shown to be dose-dependent with faster elimination at lower dose levels. The clinical dose of N8-GP provides a substantially lower PEG exposure (50-75U/kg; PEG load of <0.002mg/kg) when compared to the PEG doses investigated in this paper (0.03-200mg/kg). This may imply an even faster clearance of the PEG-moiety after N8-GP administration of clinically relevant doses. PMID:26517963

  2. Effects of chlordecone on 20-hydroxyecdysone concentration and chitobiase activity in a decapod crustacean, Macrobrachium rosenbergii.

    PubMed

    Lafontaine, Anne; Gismondi, Eric; Boulangé-Lecomte, Céline; Geraudie, Perrine; Dodet, Nathalie; Caupos, Fanny; Lemoine, Soazig; Lagadic, Laurent; Thomé, Jean-Pierre; Forget-Leray, Joëlle

    2016-07-01

    Chlordecone (CLD) is an organochlorine insecticide abundant in aquatic environment of the French West Indies. However, few studies have investigated its impact on freshwater invertebrates. Whereas CLD is suspected of inducing endocrine disruption, this work aimed to study the effects of environmentally relevant concentrations of CLD on the 20-hydroxyecdysone (20-HE) hormone concentration and on the chitobiase activity, both having key roles in the molting process of crustaceans. In addition, the bioaccumulation of CLD was measured in the muscle tissue of Macrobrachium rosenbergii to underline potential dose-response relationship. The results have shown that CLD was bioaccumulated in exposed organisms according to a trend to a dose-response relationship. Moreover, it was observed that CLD decreased the 20-HE concentration in exposed prawns when compared to control, whatever the duration of exposure, as well as it inhibited the chitobiase activity after 30days of exposure. The present study indicates that CLD could interfere with molting process of M. rosenbergii by disturbing the 20-HE concentration and the activity of chitobiase, suggesting consequences at the long term on the shrimp development. This study also confirmed that CLD could be an endocrine disruptor in decapod crustaceans, as it was already observed in vertebrates. PMID:27108204

  3. Quantitative assessment of hsp70, IL-1β and TNF-α in the spinal cord of dogs with E40K SOD1-associated degenerative myelopathy.

    PubMed

    Lovett, M C; Coates, J R; Shu, Y; Oglesbee, M J; Fenner, W; Moore, S A

    2014-05-01

    Inflammation is involved in the pathogenesis of many neurodegenerative diseases. Canine degenerative myelopathy (DM) is a progressive adult-onset neurodegenerative disease commonly associated with an E40K missense mutation in the SOD1 gene. DM has many similarities to some familial forms of human amyotrophic lateral sclerosis (ALS) and may serve as an important disease model for therapy development. Pro-inflammatory mediators such as interleukin (IL)-1β, tumor necrosis factor (TNF)-α and heat shock protein (hsp) 70 play a role in the pathogenesis of ALS. The focus of the current work was to determine whether an inflammatory phenotype is present in canine DM as defined by IL-1β, TNF-α, and hsp70 responses in cerebrospinal fluid (CSF) and spinal cord tissue. Concentrations of hsp70, IL-1β and TNF-α were below the limits of detection by ELISA in the CSF of both normal and DM-affected dogs. Immunohistochemical staining for hsp70 was significantly increased in ependymal cells lining the spinal cord central canal of DM-affected dogs (P = 0.003). This was not associated with increased IL-1β or TNF-α staining, but was associated with increased CD18 staining in the gray matter of DM-affected dogs. These results suggest that hsp70 in spinal cord tissue is a potential inflammatory signature in canine DM. PMID:24662024

  4. Effect of active-ion concentration on holmium fibre laser efficiency

    SciTech Connect

    Kurkov, Andrei S; Sholokhov, E M; Marakulin, A V; Minashina, L A

    2010-08-03

    We have measured the fraction of holmium ions that relax nonradiatively to the ground level as a result of interaction at a metastable level in optical fibres with a silica-based core doped with holmium ions to 2 x 10{sup 19} - 2 x 10{sup 20} cm{sup -3}. The percentage of such ions has been shown to depend on the absolute active-ion concentration. The fibres have been used to make a number of 2.05-{mu}m lasers, and their slope efficiency has been measured. The laser efficiency decreases with increasing holmium concentration in the fibres (lasers)

  5. Physiological concentrations of zinc reduce taurine-activated GlyR responses to drugs of abuse.

    PubMed

    Kirson, Dean; Cornelison, Garrett L; Philpo, Ashley E; Todorovic, Jelena; Mihic, S John

    2013-12-01

    Taurine is an endogenous ligand acting on glycine receptors in many brain regions, including the hippocampus, prefrontal cortex, and nucleus accumbens (nAcc). These areas also contain low concentrations of zinc, which is known to potentiate glycine receptor responses. Despite an increasing awareness of the role of the glycine receptor in the rewarding properties of drugs of abuse, the possible interactions of these compounds with zinc has not been thoroughly addressed. Two-electrode voltage-clamp electrophysiological experiments were performed on α1, α2 α1β and α2β glycine receptors expressed in Xenopus laevis oocytes. The effects of zinc alone, and zinc in combination with other positive modulators on the glycine receptor, were investigated when activated by the full agonist glycine versus the partial agonist taurine. Low concentrations of zinc enhanced responses of maximally-effective concentrations of taurine but not glycine. Likewise, chelation of zinc from buffers decreased responses of taurine- but not glycine-mediated currents. Potentiating concentrations of zinc decreased ethanol, isoflurane, and toluene enhancement of maximal taurine currents with no effects on maximal glycine currents. Our findings suggest that the concurrence of high concentrations of taurine and low concentrations of zinc attenuate the effects of additional modulators on the glycine receptor, and that these conditions are more representative of in vivo functioning than effects seen when these modulators are applied in isolation. PMID:23973295

  6. Physiological concentrations of zinc reduce taurine-activated GlyR responses to drugs of abuse

    PubMed Central

    Kirson, Dean; Cornelison, Garrett L.; Philpo, Ashley E.; Todorovic, Jelena; Mihic, S. John

    2013-01-01

    Taurine is an endogenous ligand acting on glycine receptors in many brain regions, including the hippocampus, prefrontal cortex, and nucleus accumbens (nAcc). These areas also contain low concentrations of zinc, which is known to potentiate glycine receptor responses. Despite an increasing awareness of the role of the glycine receptor in the rewarding properties of drugs of abuse, the possible interactions of these compounds with zinc has not been thoroughly addressed. Two-electrode voltage-clamp electrophysiological experiments were performed on α1, α2 α1β and a2β glycine receptors expressed in Xenopus laevis oocytes. The effects of zinc alone, and zinc in combination with other positive modulators on the glycine receptor, were investigated when activated by the full agonist glycine versus the partial agonist taurine. Low concentrations of zinc enhanced responses of maximally-effective concentrations of taurine but not glycine. Likewise, chelation of zinc from buffers decreased responses of taurine- but not glycine-mediated currents. Potentiating concentrations of zinc decreased ethanol, isoflurane, and toluene enhancement of maximal taurine currents with no effects on maximal glycine currents. Our findings suggest that the concurrence of high concentrations of taurine and low concentrations of zinc attenuate the effects of additional modulators on the glycine receptor, and that these conditions are more representative of in vivo functioning than effects seen when these modulators are applied in isolation. PMID:23973295

  7. Vitamin E Concentrations in Adults with HIV/AIDS on Highly Active Antiretroviral Therapy

    PubMed Central

    Kaio, Daniella J. Itinoseki; Rondó, Patricia Helen C.; Luzia, Liania Alves; Souza, José Maria P.; Firmino, Aline Vale; Santos, Sigrid Sousa

    2014-01-01

    HIV/AIDS patients are probably more predisposed to vitamin E deficiency, considering that they are more exposed to oxidative stress. Additionally, there are an extensive number of drugs in the highly active antiretroviral therapy (HAART) regimens that may interfere with vitamin E concentrations. The objective of this study was to compare serum concentrations of alpha-tocopherol in 182 HIV/AIDS patients receiving different HAART regimens. The patients were divided into three groups according to regimen: nucleoside analog reverse-transcriptase inhibitors (NRTIs) + non-nucleoside analog reverse-transcriptase inhibitors (NNRTIs); NRTIs + protease inhibitors + ritonavir; NRTIs + other classes. Alpha-tocopherol was assessed by high-performance liquid chromatography. Multiple linear regression analysis was used to evaluate the effects of HAART regimen, time of use, and compliance with the regimen on alpha-tocopherol concentrations. Alpha-tocopherol concentrations were on average 4.12 μmol/L lower for the NRTIs + other classes regimen when compared to the NRTIs + NNRTIs regimen (p = 0.037). A positive association (p < 0.001) was observed between alpha-tocopherol and cholesterol concentrations, a finding due, in part, to the relationship between liposoluble vitamins and lipid profile. This study demonstrated differences in alpha-tocopherol concentrations between patients using different HAART regimens, especially regimens involving the use of new drugs. Long-term prospective cohort studies are needed to monitor vitamin E status in HIV/AIDS patients since the beginning of treatment. PMID:25225815

  8. Effect of elevated serum prolactin concentrations on cytokine production and natural killer cell activity.

    PubMed

    Clodi, M; Svoboda, T; Kotzmann, H; Deyssig, R; Woloszczuk, W; Zielinski, C C; Luger, A

    1992-12-01

    In vitro and in vivo studies in rodents and human suggested an immunostimulatory effect of prolactin. The aim of the present study was to determine the impact of chronically elevated serum prolactin concentrations on the immune system in patients with prolactinomas. For this purpose parameters of the humoral and cellular immune system were studied in seven patients with prolactinomas on two occasions (1) when their serum prolactin concentration had been normalized through treatment with dopamine agonists and (2) when their serum prolactin concentration was high. Serum concentrations of immunoglobulines, interleukin 1, 3 and 6, TNF-alpha, interferon-gamma and the soluble interleukin 2 receptor, leukocyte subsets and the natural killer cell activity were found to be within the normal range on both occasions, i.e. at normal and at high serum prolactin concentrations. The assumption could be made that long-lasting elevation of serum prolactin concentration induces adaptive changes when the acute stimulatory effects of prolactin on several parameters of the immune system have subsided. PMID:1369584

  9. Influence of Traffic Activity on Heavy Metal Concentrations of Roadside Farmland Soil in Mountainous Areas

    PubMed Central

    Zhang, Fan; Yan, Xuedong; Zeng, Chen; Zhang, Man; Shrestha, Suraj; Devkota, Lochan Prasad; Yao, Tandong

    2012-01-01

    Emission of heavy metals from traffic activities is an important pollution source to roadside farmland ecosystems. However, little previous research has been conducted to investigate heavy metal concentrations of roadside farmland soil in mountainous areas. Owing to more complex roadside environments and more intense driving conditions on mountainous highways, heavy metal accumulation and distribution patterns in farmland soil due to traffic activity could be different from those on plain highways. In this study, design factors including altitude, roadside distance, terrain, and tree protection were considered to analyze their influences on Cu, Zn, Cd, and Pb concentrations in farmland soils along a mountain highway around Kathmandu, Nepal. On average, the concentrations of Cu, Zn, Cd, and Pb at the sampling sites are lower than the tolerable levels. Correspondingly, pollution index analysis does not show serious roadside pollution owing to traffic emissions either. However, some maximum Zn, Cd, and Pb concentrations are close to or higher than the tolerable level, indicating that although average accumulations of heavy metals pose no hazard in the region, some spots with peak concentrations may be severely polluted. The correlation analysis indicates that either Cu or Cd content is found to be significantly correlated with Zn and Pb content while there is no significant correlation between Cu and Cd. The pattern can be reasonably explained by the vehicular heavy metal emission mechanisms, which proves the heavy metals’ homology of the traffic pollution source. Furthermore, the independent factors show complex interaction effects on heavy metal concentrations in the mountainous roadside soil, which indicate quite a different distribution pattern from previous studies focusing on urban roadside environments. It is found that the Pb concentration in the downgrade roadside soil is significantly lower than that in the upgrade soil while the Zn concentration in the

  10. Vasopressin activates Akt/mTOR pathway in smooth muscle cells cultured in high glucose concentration

    SciTech Connect

    Montes, Daniela K.; Brenet, Marianne; Muñoz, Vanessa C.; Burgos, Patricia V.; Villanueva, Carolina I.; Figueroa, Carlos D.; González, Carlos B.

    2013-11-29

    Highlights: •AVP induces mTOR phosphorylation in A-10 cells cultured in high glucose concentration. •The mTOR phosphorylation is mediated by the PI3K/Akt pathway activation. •The AVP-induced mTOR phosphorylation inhibited autophagy and stimulated cell proliferation. -- Abstract: Mammalian target of rapamycin (mTOR) complex is a key regulator of autophagy, cell growth and proliferation. Here, we studied the effects of arginine vasopressin (AVP) on mTOR activation in vascular smooth muscle cells cultured in high glucose concentration. AVP induced the mTOR phosphorylation in A-10 cells grown in high glucose, in contrast to cells cultured in normal glucose; wherein, only basal phosphorylation was observed. The AVP-induced mTOR phosphorylation was inhibited by a PI3K inhibitor. Moreover, the AVP-induced mTOR activation inhibited autophagy and increased thymidine incorporation in cells grown in high glucose. This increase was abolished by rapamycin which inhibits the mTORC1 complex formation. Our results suggest that AVP stimulates mTOR phosphorylation by activating the PI3K/Akt signaling pathway and, subsequently, inhibits autophagy and raises cell proliferation in A-10 cells maintained in high glucose concentration.

  11. Impact of alginate concentration on the viability, cryostorage, and angiogenic activity of encapsulated fibroblasts.

    PubMed

    Mohanty, Swetaparna; Wu, Yang; Chakraborty, Nilay; Mohanty, Pravansu; Ghosh, Gargi

    2016-08-01

    Cryopreservation or cryostorage of tissue engineered constructs can enhance the off-the shelf availability of these products and thus can potentially facilitate the commercialization or clinical translation of tissue engineered products. Encapsulation of cells within hydrogel matrices, in particular alginate, is widely used for fabrication of tissue engineered constructs. While previous studies have explored the cryopreservation response of cells encapsulated within alginate matrices, systematic investigation of the impact of alginate concentration on the metabolic activity and functionality of cryopreserved cells is lacking. The objective of the present work is to determine the metabolic and angiogenic activity of cryopreserved human dermal fibroblasts encapsulated within 1.0%, 1.5% and 2.0% (w/v) alginate matrices. In addition, the goal is to compare the efficacy of dimethyl sulfoxide (DMSO) and trehalose as cryoprotectant. Our study revealed that the concentration of alginate plays a significant role in the cryopreservation response of encapsulated cells. The lowest metabolic activity of the cryopreserved cells was observed in 1% alginate microspheres. When higher concentration of alginate was utilized for cell encapsulation, the metabolic and angiogenic activity of the cells frozen in the absence of cryoprotectants was comparable to that observed in the presence of DMSO or trehalose. PMID:27157752

  12. The Concentration Dependence of Active Potassium Transport in the Human Red Blood Cell*

    PubMed Central

    Sachs, John R.; Welt, Louis G.

    1967-01-01

    The relation between the active potassium influx in the human red blood cell and the extracellular potassium concentration does not appear to be consistent with the Michaelis-Menten model, but is adequately described by a model in which two potassium ions are required simultaneously at some site or sites in the transport mechanism before transport occurs. The same type of relation appears to exist between that portion of the sodium outflux that requires the presence of extracellular potassium and the extracellular potassium concentration. Rubidium, cesium, and lithium, which are apparently transported by the same system that transports potassium, stimulate the potassium influx when both potassium and the second ion are present at low concentrations, as is predicted by the two-site model. PMID:6018751

  13. Primary centers and secondary concentrations of tectonic activity through time in the western hemisphere of Mars

    USGS Publications Warehouse

    Anderson, R.C.; Dohm, J.M.; Golombek, M.P.; Haldemann, A.F.C.; Franklin, B.J.; Tanaka, K.L.; Lias, J.; Peer, B.

    2001-01-01

    Five main stages of radial and concentric structures formed around Tharsis from the Noachian through the Amazonian as determined by geologic mapping of 24,452 structures within the stratigraphic framework of Mars and by testing their radial and concentric orientations. Tectonic activity peaked in the Noachian (stage 1) around the largest center, Claritas, an elongate center extending more than 20?? in latitude and defined by about half of the total grabens which are concentrated in the Syria Planum, Thaumasia, and Tempe Terra regions. During the Late Noachian and Early Hesperian (stage 2), extensional structures formed along the length of present-day Valles Marineris and in Thaumasia (with a secondary concentration near Warrego Vallis) radial to a region just to the south of the central margin of Valles Marineris. Early Hesperian (stage 3) radial grabens in Pavonis, Syria, Ulysses, and Tempe Terra and somewhat concentric wrinkle ridges in Lunae and Solis Plana and in Thaumasia, Sirenum, Memnonia, and Amazonis are centered northwest of Syria with secondary centers at Thaumasia, Tempe Terra, Ulysses Fossae, and western Valles Marineris. Late Hesperian/Early Amazonian (stage 4) structures around Alba Patera, the northeast trending alignment of Tharsis Montes, and Olympus Mons appears centered on Alba Patera. Stage 5 structures (Middle-Late Amazonian) represent the last pulse of Tharsis-related activity and are found around the large shield volcanoes and are centered near Pavonis Mons. Tectonic activity around Tharsis began in the Noachian and generally decreased through geologic time to the Amazonian. Statistically significant radial distributions of structures formed during each stage, centered at different locations within the higher elevations of Tharsis. Secondary centers of radial structures during many of the stages appear related to previously identified local magmatic centers that formed at different times and locations throughout Tharsis. Copyright 2001 by

  14. Antimicrobial activity of clove oil dispersed in a concentrated sugar solution.

    PubMed

    Briozzo, J; Núñez, L; Chirife, J; Herszage, L; D'Aquino, M

    1989-01-01

    Essential oil of clove, dispersed (0.4% v/v) in a concentrated sugar solution, had a marked germicidal effect against various bacteria and Candida albicans. Staphylococcus aureus (five strains), Klebsiella pneumoniae, Pseudomonas aeruginosa, Clostridium perfringens, and Escherichia coli inoculated at a level of 10(7) cfu/ml, and C. albicans (inoculum 4.0 x 10(5) cfu/ml) were killed (greater than 99.999%) after 2-7 min in a laboratory broth supplemented with 63% (v/w) of sugar, and containing 0.4% (v/w) of essential oil of clove. Added organic matter (i.e. human or bovine serum) did not impair its antimicrobial activity. Sugar was not necessary for the antimicrobial activity of clove oil, but the concentrated sugar solution provided a good vehicle for obtaining an oil dispersion that is relatively stable for certain practical applications. PMID:2542213

  15. Investigation of the Photo-activation Analysis on Concentrations of Various Materials

    NASA Astrophysics Data System (ADS)

    Cesur, A.; Karakoc, M.; Boztosun, I.; Dapo, H.

    2015-04-01

    It is possible to excite atomic nuclei electromagnetically and even separate proton or neutron from a sample which is exposed to gamma rays by a clinical linac. Thus, the determination of the elemental concentration of a sample by photo-activation analysis is a reasonable attempt since it is related to the detailed analysis of the photonuclear reaction of an intended element. In this study, in order to get the proof of principle for photo-activation a titanium dioxide and a 10 kurus Turkish coin samples are irradiated with high energy bremsstrahlung photons at the end-point energy of 18 MeV and their zinc and copper concentrations are determined by a precise measurement with a high purity germanium detector.

  16. Active/passive microwave sensor comparison of MIZ-ice concentration estimates. [Marginal Ice Zone (MIZ)

    NASA Technical Reports Server (NTRS)

    Burns, B. A.; Cavalieri, D. J.; Keller, M. R.

    1986-01-01

    Active and passive microwave data collected during the 1984 summer Marginal Ice Zone Experiment in the Fram Strait (MIZEX 84) are used to compare ice concentration estimates derived from synthetic aperture radar (SAR) data to those obtained from passive microwave imagery at several frequencies. The comparison is carried out to evaluate SAR performance against the more established passive microwave technique, and to investigate discrepancies in terms of how ice surface conditions, imaging geometry, and choice of algorithm parameters affect each sensor. Active and passive estimates of ice concentration agree on average to within 12%. Estimates from the multichannel passive microwave data show best agreement with the SAR estimates because the multichannel algorithm effectively accounts for the range in ice floe brightness temperatures observed in the MIZ.

  17. Effect of Fe doping concentration on photocatalytic activity of ZnO nanosheets under natural sunlight

    SciTech Connect

    Khokhra, Richa; Kumar, Rajesh

    2015-05-15

    A facile room temperature, aqueous solution-based chemical method has been adopted for large-scale synthesis of Fe doped ZnO nanosheets. The XRD and SEM results reveal the as-synthesized products well crystalline and accumulated by large amount of interweave nanosheets, respectively. Energy dispersive spectroscopy data confirmed Fe doping of the ZnO nanosheets with a varying Fe concentration. The photoluminescence spectrum reveals a continuous suppression of defect related emissions intensity by increasing the concentration of the Fe ion. A photocatalytic activity using these samples under sunlight irradiation in the mineralization of methylene blue dye was investigated. The photocatalytic activity of Fe doped ZnO nanosheets depends upon the presence of surface oxygen vacancies.

  18. Gastroprotective activity of reconstituted red fruit pulp concentrate of Citrullus lanatus in rats

    PubMed Central

    Sharma, Swapnil; Dave, Vivek; Paliwal, Sarvesh; Dwivedi, Jaya; Jain, Sonika

    2014-01-01

    Aim: This study was carried out to evaluate the gastroprotective potential of the aqueous fruit pulp concentrate of Citrullus lanatus citroides (CLC) on pyloric ligation and indomethacin-induced ulcer in Wistar albino rats. Materials and methods: In indomethacin-induced ulcer model, CLC was administered in the doses of 250 mg/kg, 500 mg/kg and 1000 mg/kg body weight orally, tds for 5 days. The antiulcer activity was determined via observing reduction in ulcer index whereas in the pyloric ligation model, the gastroprotective effect of CLC was assessed from the alteration in volume of gastric juice, pH, free and total acidity, protein concentration in gastric juice. Further lipid peroxide (LPO), and activities of enzymic antioxidants such as superoxide dismutase (SOD) and catalase (CAT) was also determined along with the levels of hexose, hexosamine, sialic acid, fucose in gastric mucosa. Results: In both models, treatment with CLC caused a significant reduction in lesion index when compared to vehicle treated group, providing evidence for antiulcer capacity. In pyloric ligation model, pretreatment with CLC resulted in significant increase in pH, enzymic antioxidants, that is, SOD, CAT, with a significant decrease in volume of gastric juice, free and total acidity, protein concentration, acid output, and LPO levels respectively. The presence of the flavonoids and polyphenols may be responsible for the gastroprotective effect of CLC. Conclusions: The aqueous fruit pulp concentrate of CLC showed significant gastroprotective potential against pyloric ligation and indomethacin-induced ulceration in rats. PMID:25861146

  19. Low concentration of arsenite exacerbates UVR-induced DNA strand breaks by inhibiting PARP-1 activity

    SciTech Connect

    Qin Xujun; Hudson, Laurie G.; Liu Wenlan; Timmins, Graham S.; Liu Kejian

    2008-10-01

    Epidemiological studies have associated arsenic exposure with many types of human cancers. Arsenic has also been shown to act as a co-carcinogen even at low concentrations. However, the precise mechanism of its co-carcinogenic action is unknown. Recent studies indicate that arsenic can interfere with DNA-repair processes. Poly(ADP-ribose) polymerase (PARP)-1 is a zinc-finger DNA-repair protein, which can promptly sense DNA strand breaks and initiate DNA-repair pathways. In the present study, we tested the hypothesis that low concentrations of arsenic could inhibit PAPR-1 activity and so exacerbate levels of ultraviolet radiation (UVR)-induced DNA strand breaks. HaCat cells were treated with arsenite and/or UVR, and then DNA strand breaks were assessed by comet assay. Low concentrations of arsenite ({<=} 2 {mu}M) alone did not induce significant DNA strand breaks, but greatly enhanced the DNA strand breaks induced by UVR. Further studies showed that 2 {mu}M arsenite effectively inhibited PARP-1 activity. Zinc supplementation of arsenite-treated cells restored PARP-1 activity and significantly diminished the exacerbating effect of arsenite on UVR-induced DNA strand breaks. Importantly, neither arsenite treatment, nor zinc supplementation changed UVR-triggered reactive oxygen species (ROS) formation, suggesting that their effects upon UVR-induced DNA strand breaks are not through a direct free radical mechanism. Combination treatments of arsenite with PARP-1 inhibitor 3-aminobenzamide or PARP-1 siRNA demonstrate that PARP-1 is the target of arsenite. Together, these findings show that arsenite at low concentration exacerbates UVR-induced DNA strand breaks by inhibiting PARP-1 activity, which may represent an important mechanism underlying the co-carcinogenicity of arsenic.

  20. Comparison of digoxin concentration in plastic serum tubes with clot activator and heparinized plasma tubes

    PubMed Central

    Dukić, Lora; Šimundić, Ana-Maria; Malogorski, Davorin

    2014-01-01

    Introduction: Sample type recommended by the manufacturer for the digoxin Abbott assay is either serum collected in glass tubes or plasma (sodium heparin, lithium heparin, citrate, EDTA or oxalate as anticoagulant) collected in plastic tubes. In our hospital samples are collected in plastic tubes. Our hypothesis was that the serum sample collected in plastic serum tube can be used interchangeably with plasma sample for measurement of digoxin concentration. Our aim was verification of plastic serum tubes for determination of digoxin concentration. Materials and methods: Concentration of digoxin was determined simultaneously in 26 venous blood plasma (plastic Vacuette, LH Lithium heparin) and serum (plastic Vacuette, Z Serum Clot activator; both Greiner Bio-One GmbH, Kremsmünster, Austria) samples, on Abbott AxSYM analyzer using the original Abbott Digoxin III assay (Abbott, Wiesbaden, Germany). Tube comparability was assessed using the Passing Bablok regression and Bland-Altman plot. Results: Serum and plasma digoxin concentrations are comparable. Passing Bablok intercept (0.08 [95% CI = −0.10 to 0.20]) and slope (0.99 [95% CI = 0.92 to 1.11]) showed there is no constant or proportional error. Conclusion: Blood samples drawn in plastic serum tubes and plastic plasma tubes can be interchangeably used for determination of digoxin concentration. PMID:24627723

  1. Quantifying the 3D Odorant Concentration Field Used by Actively Tracking Blue Crabs

    NASA Astrophysics Data System (ADS)

    Webster, D. R.; Dickman, B. D.; Jackson, J. L.; Weissburg, M. J.

    2007-11-01

    Blue crabs and other aquatic organisms locate food and mates by tracking turbulent odorant plumes. The odorant concentration fluctuates unpredictably due to turbulent transport, and many characteristics of the fluctuation pattern have been hypothesized as useful cues for orienting to the odorant source. To make a direct linkage between tracking behavior and the odorant concentration signal, we developed a measurement system based the laser induced fluorescence technique to quantify the instantaneous 3D concentration field surrounding actively tracking blue crabs. The data suggest a correlation between upstream walking speed and the concentration of the odorant signal arriving at the antennule chemosensors, which are located near the mouth region. More specifically, we note an increase in upstream walking speed when high concentration bursts arrive at the antennules location. We also test hypotheses regarding the ability of blue crabs to steer relative to the plume centerline based on the signal contrast between the chemosensors located on their leg appendages. These chemosensors are located much closer to the substrate compared to the antennules and are separated by the width of the blue crab. In this case, it appears that blue crabs use the bilateral signal comparison to track along the edge of the plume.

  2. Response of oxidative enzyme activities to nitrogen deposition affects soil concentrations of dissolved organic carbon

    USGS Publications Warehouse

    Waldrop, M.P.; Zak, D.R.

    2006-01-01

    Recent evidence suggests that atmospheric nitrate (NO3- ) deposition can alter soil carbon (C) storage by directly affecting the activity of lignin-degrading soil fungi. In a laboratory experiment, we studied the direct influence of increasing soil NO 3- concentration on microbial C cycling in three different ecosystems: black oak-white oak (BOWO), sugar maple-red oak (SMRO), and sugar maple-basswood (SMBW). These ecosystems span a broad range of litter biochemistry and recalcitrance; the BOWO ecosystem contains the highest litter lignin content, SMRO had intermediate lignin content, and SMBW leaf litter has the lowest lignin content. We hypothesized that increasing soil solution NO 3- would reduce lignolytic activity in the BOWO ecosystem, due to a high abundance of white-rot fungi and lignin-rich leaf litter. Due to the low lignin content of litter in the SMBW, we further reasoned that the NO3- repression of lignolytic activity would be less dramatic due to a lower relative abundance of white-rot basidiomycetes; the response in the SMRO ecosystem should be intermediate. We increased soil solution NO3- concentrations in a 73-day laboratory incubation and measured microbial respiration and soil solution dissolved organic carbon (DOC) and phenolics concentrations. At the end of the incubation, we measured the activity of ??-glucosidase, N-acetyl-glucosaminidase, phenol oxidase, and peroxidase, which are extracellular enzymes involved with cellulose and lignin degradation. We quantified the fungal biomass, and we also used fungal ribosomal intergenic spacer analysis (RISA) to gain insight into fungal community composition. In the BOWO ecosystem, increasing NO 3- significantly decreased oxidative enzyme activities (-30% to -54%) and increased DOC (+32% upper limit) and phenolic (+77% upper limit) concentrations. In the SMRO ecosystem, we observed a significant decrease in phenol oxidase activity (-73% lower limit) and an increase in soluble phenolic concentrations

  3. Bayesian Estimation of the Active Concentration and Affinity Constants Using Surface Plasmon Resonance Technology.

    PubMed

    Feng, Feng; Kepler, Thomas B

    2015-01-01

    Surface plasmon resonance (SPR) has previously been employed to measure the active concentration of analyte in addition to the kinetic rate constants in molecular binding reactions. Those approaches, however, have a few restrictions. In this work, a Bayesian approach is developed to determine both active concentration and affinity constants using SPR technology. With the appropriate prior probabilities on the parameters and a derived likelihood function, a Markov Chain Monte Carlo (MCMC) algorithm is applied to compute the posterior probability densities of both the active concentration and kinetic rate constants based on the collected SPR data. Compared with previous approaches, ours exploits information from the duration of the process in its entirety, including both association and dissociation phases, under partial mass transport conditions; do not depend on calibration data; multiple injections of analyte at varying flow rates are not necessary. Finally the method is validated by analyzing both simulated and experimental datasets. A software package implementing our approach is developed with a user-friendly interface and made freely available. PMID:26098764

  4. Using Photon Activation Analysis To Determine Concentrations Of Unknown Components In Reference Materials

    SciTech Connect

    Green, Jaromy; Sun, Zaijing; Wells, Doug; Maschner, Herb

    2011-06-01

    Using certified multi-element reference materials for instrumental analyses one frequently is confronted with the embarrassing fact that the concentration of some desired elements are not given in the respective certificate, nonetheless are detectable, e.g. by photon activation analysis (PAA). However, these elements might be determinable with sufficient quality of the results using scaling parameters and the well-known quantities of a reference element within the reference material itself. Scaling parameters include: activation threshold energy, Giant Dipole Resonance (GDR) peak and endpoint energy of the bremsstrahlung continuum; integrated photo-nuclear cross sections for the isotopes of the reference element; bremsstrahlung continuum integral; target thickness; photon flux density. Photo-nuclear cross sections from the unreferenced elements must be known, too. With these quantities, the integral was obtained for both the known and unknown elements resulting in an inference of the concentration of the unreported element based upon the reported value, thus also the concentration of the unreferenced element in the reference material. A similar method to determine elements using the basic nuclear and experimental data has been developed for thermal neutron activation analysis some time ago (k{sub 0} Method).

  5. Effect of petrochemical sludge concentrations of changes in mutagenic activity during soil bioremediation process.

    PubMed

    Morelli, I S; Vecchioli, G I; Del Panno, M T; Painceira, M T

    2001-10-01

    The present study was performed to assess the effect of the petrochemical sludge application rate on the mutagenic activity (Ames test) of soil and the persistence of mutagenic activity during laboratory soil bioremediation process. Sludge-soil systems were prepared at four different sludge application rates (1.25, 2.5, 5, and 10% w/w). Unamended soil was used as a control. Immediately following sludge application, in the absence or presence of S9, a linear correlation between sludge application rates and mutagenicity was found but differed significantly (p < 0.05) from the control system only at higher application rates (5 and 10% w/w). The direct mutagenicity of all systems decreases during the bioremediation process, and after a year of treatment only the 10% system induced a mutagenic response that was significantly different from the control system. On the other hand, an initial increase of the indirect mutagenicity was observed at all application rates. The time required for observing this increase was inversely proportional to the initial sludge concentration. After a year of treatment, the indirect mutagenicity of all sludge-amended soils was not significantly different but was significantly different from the unamended soils. The persistence of the direct mutagenic activity of the sludge-amended soils was related to the sludge concentration, whereas the indirect mutagenic persistence was related to the relationship between easily degradable hydrocarbons and polynuclear aromatic hydrocarbons concentration and independent from the initial application rate. PMID:11596747

  6. Concentration of enteric virus indicator from seawater using granular activated carbon.

    PubMed

    Cormier, Jiemin; Gutierrez, Miguel; Goodridge, Lawrence; Janes, Marlene

    2014-02-01

    Fecal contamination of shellfish growing seawater with enteric viruses is often associated with human outbreaks of gastroenteritis. Male specific bacteriophage MS2 is correlated with those of enteric viruses in a wide range of water environments and has been used widely as a surrogate for pathogenic waterborne viruses. Since viruses in contaminated water are usually at low levels, the development of methods to concentrate viruses from water is crucial for detection purposes. In the present study, granular activated carbon was evaluated for concentration of MS2 from artificial seawater, and different parameters of the seawater were also compared. Recovery of MS2 from warm seawater (37°C) was found to be significantly greater than from cold seawater (4 and 20°C), and even greater than from fresh water (4, 20 and 37°C); the difference between seawater and fresh water became less profound when the temperatures of both were below 37°C. Although not of statistical significance, recovery of MS2 from low salinity seawater (10 and 20 parts per thousand, ppt) was greater than from high salinity seawater (30 and 40ppt). One gram of granular activated carbon was able to extract 6-log plaque forming units (PFU) of MS2 from 500ml seawater at 37°C. This study demonstrated that granular activated carbon can concentrate an enteric virus indicator from shellfish growing seawater effectively. PMID:24269798

  7. Bayesian Estimation of the Active Concentration and Affinity Constants Using Surface Plasmon Resonance Technology

    PubMed Central

    Feng, Feng; Kepler, Thomas B.

    2015-01-01

    Surface plasmon resonance (SPR) has previously been employed to measure the active concentration of analyte in addition to the kinetic rate constants in molecular binding reactions. Those approaches, however, have a few restrictions. In this work, a Bayesian approach is developed to determine both active concentration and affinity constants using SPR technology. With the appropriate prior probabilities on the parameters and a derived likelihood function, a Markov Chain Monte Carlo (MCMC) algorithm is applied to compute the posterior probability densities of both the active concentration and kinetic rate constants based on the collected SPR data. Compared with previous approaches, ours exploits information from the duration of the process in its entirety, including both association and dissociation phases, under partial mass transport conditions; do not depend on calibration data; multiple injections of analyte at varying flow rates are not necessary. Finally the method is validated by analyzing both simulated and experimental datasets. A software package implementing our approach is developed with a user-friendly interface and made freely available. PMID:26098764

  8. Purification and functional analysis of a 40 kD protein extracted from the Strombus decorus persicus mollusk shells.

    PubMed

    Pokroy, Boaz; Zolotoyabko, Emil; Adir, Noam

    2006-02-01

    A 40 kD protein has been extracted from the biomineral matrix of the calcium carbonate gastropod shell of Strombus decorus persicus. The protein was isolated by decalcification and ion exchange HPLC. We have named this protein ACLS40, i.e., aragonite crossed-lamellar structure protein. A partial sequence of the isolated ACLS40 and amino acid analysis both indicate that it does not belong to the family of very acidic proteins, i.e., rich in aspartic and glutamic residues. The shell-extracted protein shows the ability to stabilize calcium carbonate in vitro, in the form of thermodynamically unstable vaterite polymorph, and to inhibit the growth of calcite. PMID:16471929

  9. Qualification of a 40 kA Nb{sub 3}Sn superconducting conductor for NET/ITER coils

    SciTech Connect

    Bessette, D.; Duchateau, J.L.; Decool, P.; Turck, B.; Blau, B.

    1994-07-01

    A 40 kA Nb{sub 3}Sn conductor, designed to operate with forced helium flow at 4.5 K was tested in the SULTAN III facility, (I{sub max} = 50kA, B{sub max} (background) = 11T). The test sample and the operating conditions of the test facility are described. Two measurement procedures were used to investigate the conductor behavior near the critical value: sample current or temperature are increased up to the quench with background field and temperature or current reciprocally kept at steady state. The critical current of the conductor could be measured with the same criterion as for the basic strand (0.1 {mu}V/cm). The obtained results are discussed and compared with the basic strand performances. In addition some results on the thermohydraulic behavior of the CIC conductor are presented.

  10. Study of the adsorption of Cd and Zn onto an activated carbon: Influence of pH, cation concentration, and adsorbent concentration

    SciTech Connect

    Seco, A.; Marzal, P.; Gabaldon, C.; Ferrer, J.

    1999-06-01

    The single adsorption of Cd and Zn from aqueous solutions has been investigated on Scharlau Ca 346 granular activated carbon in a wide range of experimental conditions: pH, metal concentration, and carbon concentration. The results showed the efficiency of the activated carbon as sorbent for both metals. Metal removals increase on raising the pH and carbon concentration, and decrease on raising the initial metal concentration. The adsorption processes have been modeled using the surface complex formation (SCF) Triple Layer Model (TLM). The adsorbent TLM parameters were determined. Modeling has been performed assuming a single surface bidentate species or an overall surface species with fractional stoichiometry. The bidentate stoichiometry successfully predicted cadmium and zinc removals in all the experimental conditions. The Freundlich isotherm has been also checked.

  11. Coat protein activation of alfalfa mosaic virus replication is concentration dependent.

    PubMed

    Guogas, Laura M; Laforest, Siana M; Gehrke, Lee

    2005-05-01

    Alfalfa mosaic virus (AMV) and ilarvirus RNAs are infectious only in the presence of the viral coat protein; therefore, an understanding of coat protein's function is important for defining viral replication mechanisms. Based on in vitro replication experiments, the conformational switch model states that AMV coat protein blocks minus-strand RNA synthesis (R. C. Olsthoorn, S. Mertens, F. T. Brederode, and J. F. Bol, EMBO J. 18:4856-4864, 1999), while another report states that coat protein present in an inoculum is required to permit minus-strand synthesis (L. Neeleman and J. F. Bol, Virology 254:324-333, 1999). Here, we report on experiments that address these contrasting results with a goal of defining coat protein's function in the earliest stages of AMV replication. To detect coat-protein-activated AMV RNA replication, we designed and characterized a subgenomic luciferase reporter construct. We demonstrate that activation of viral RNA replication by coat protein is concentration dependent; that is, replication was strongly stimulated at low coat protein concentrations but decreased progressively at higher concentrations. Genomic RNA3 mutations preventing coat protein mRNA translation or disrupting coat protein's RNA binding domain diminished replication. The data indicate that RNA binding and an ongoing supply of coat protein are required to initiate replication on progeny genomic RNA transcripts. The data do not support the conformational switch model's claim that coat protein inhibits the initial stages of viral RNA replication. Replication activation may correlate with low local coat protein concentrations and low coat protein occupancy on the multiple binding sites present in the 3' untranslated regions of the viral RNAs. PMID:15827190

  12. Tracking Dissolved Methane Concentrations near Active Seeps and Gas Hydrates: Sea of Japan.

    NASA Astrophysics Data System (ADS)

    Snyder, G. T.; Aoki, S.; Matsumoto, R.; Tomaru, H.; Owari, S.; Nakajima, R.; Doolittle, D. F.; Brant, B.

    2015-12-01

    A number of regions in the Sea of Japan are known for active gas venting and for gas hydrate exposures on the sea floor. In this investigation we employed several gas sensors mounted on a ROV in order to determine the concentrations of dissolved methane in the water near these sites. Methane concentrations were determined during two-second intervals throughout each ROV deployment during the cruise. The methane sensor deployments were coupled with seawater sampling using Niskin bottles. Dissolved gas concentrations were later measured using gas chromatography in order to compare with the sensor results taken at the same time. The observed maximum dissolved methane concentrations were much lower than saturation values, even when the ROV manipulators were in contact with gas hydrate. Nonetheless, dissolved concentrations did reach several thousands of nmol/L near gas hydrate exposures and gas bubbles, more than two orders of magnitude over the instrumental detection limits. Most of the sensors tested were able to detect dissolved methane concentrations as low as 10 nmol/L which permitted detection when the ROV approached methane plume sites, even from several tens of meters above the sea floor. Despite the low detection limits, the methane sensors showed variable response times when returning to low-background seawater (~5nM). For some of the sensors, the response time necessary to return to background values occurred in a matter of minutes, while for others it took several hours. Response time, as well as detection limit, should be an important consideration when selecting methane sensors for ROV or AUV investigations. This research was made possible, in part, through funding provided by the Japanese Ministry of Economy, Trade and Industry (METI).

  13. The relationship between aviation activities and ultrafine particulate matter concentrations near a mid-sized airport

    NASA Astrophysics Data System (ADS)

    Hsu, Hsiao-Hsien; Adamkiewicz, Gary; Andres Houseman, E.; Vallarino, Jose; Melly, Steven J.; Wayson, Roger L.; Spengler, John D.; Levy, Jonathan I.

    2012-04-01

    Aircraft contribute to emissions of ultrafine particulate matter (UFP) and other air pollutants, with corresponding impacts on community-level exposures near active airports. However, it is challenging to isolate the contribution of aircraft from local road traffic and other nearby combustion sources. In this study, we used high-resolution monitoring and flight activity data to quantify contributions from landing and take-off operations (LTO) to UFP concentrations. UFP concentrations were monitored with 1-min resolution at four monitoring sites surrounding T.F. Green Airport in Warwick, RI, in three one-week campaigns across different seasons in 2007 and 2008. Along with pollutant monitoring, wind data were collected and runway-specific LTO data were obtained from airport officials. We developed regression models in which wind speed and direction were included as a nonparametric smooth spatial term using thin-plate splines applied to wind velocity vectors and fitted using linear mixed models. To better pinpoint the timing in the LTO cycle most contributing to elevated concentrations, we used regression models with lag terms for flight activity (ranging from 5 min before to 5 min after the departure or arrival). Results suggest positive associations between UFP concentrations and LTO activities, especially for departures when an aircraft moves near or passes a monitoring site. Departures of jet engine aircrafts on a runway proximate to one of the monitors have a maximal impact 1 min prior to take-off, with median absolute contributions during those minutes of 7400 particles cm-3 (range: 1100-70,000 particles cm-3). Across all observations, our models indicate median (95th, 99th percentile) percent contribution for all LTO activities of 9.8% (54%, 72%) and 6.6% (39%, 55%) for the two sites proximate to the airport's principal runway, and 4.7% (24%, 36%) and 1.8% (22%, 31%) for the remaining two sites. Our analysis illustrates the complexity of aviation impacts on

  14. Ingestion dose from 238U, 232Th, 226Ra, 40K and 137Cs in cereals, pulses and drinking water to adult population in a high background radiation area, Odisha, India.

    PubMed

    Lenka, Pradyumna; Sahoo, S K; Mohapatra, S; Patra, A C; Dubey, J S; Vidyasagar, D; Tripathi, R M; Puranik, V D

    2013-03-01

    A natural high background radiation area is located in Chhatrapur, Odisha in the eastern part of India. The inhabitants of this area are exposed to external radiation levels higher than the global average background values, due to the presence of uranium, thorium and its decay products in the monazite sands bearing placer deposits in its beaches. The concentrations of (232)Th, (238)U, (226)Ra, (40)K and (137)Cs were determined in cereals (rice and wheat), pulses and drinking water consumed by the population residing around this region and the corresponding annual ingestion dose was calculated. The annual ingestion doses from cereals, pulses and drinking water varied in the range of 109.4-936.8, 10.2-307.5 and 0.5-2.8 µSv y(-1), respectively. The estimated total annual average effective dose due to the ingestion of these radionuclides in cereals, pulses and drinking water was 530 µSv y(-1). The ingestion dose from cereals was the highest mainly due to a high consumption rate. The highest contribution of dose was found to be from (226)Ra for cereals and drinking water and (40)K was the major dose contributor from the intake of pulses. The contribution of man-made radionuclide (137)Cs to the total dose was found to be minimum. (226)Ra was found to be the largest contributor to ingestion dose from all sources. PMID:22802517

  15. Fumonisin concentration and ceramide synthase inhibitory activity of corn, masa, and tortilla chips.

    PubMed

    Voss, Kenneth A; Norred, William P; Meredith, Filmore I; Riley, Ronald T; Stephen Saunders, D

    2006-07-01

    Nixtamalization removes fumonisins from corn and reduces their amounts in masa and tortilla products. Fumonisin concentrations and potential toxicity could be underestimated, however, if unknown but biologically active fumonisins are present. Therefore, the relative amounts of fumonisins in extracts of fumonisin-contaminated corn and its masa and tortilla chip nixtamalization products were determined with an in vitro ceramide synthase inhibition bioassay using increased sphinganine (Sa) and sphinganine to sphingosine ratio (Sa/So) as endpoints. African green monkey kidney cells (Vero cells ATCC CCL-81) were grown in 1-ml wells and exposed to 4 microl of the concentrated extracts for 48 h. The corn extract inhibited ceramide synthase as Sa (mean = 132 pmol/well) and Sa/So (mean = 2.24) were high compared to vehicle controls (Sa = 9 pmol/well; Sa/So = 0.10). Inhibitory activity (mean Sa = 14-24 pmol/well; mean Sa/So = 0.17-0.28) of the masa and tortilla chip extracts were reduced > or = 80% compared to the corn extract. Results were corroborated in a second experiment in which Sa and Sa/So of the wells treated with masa or tortilla chip extracts were reduced > or = 89% compared to those treated with the corn extract. Masa and tortilla chip FB1 concentrations (4-7 ppm) were reduced about 80-90% compared to the corn (30 ppm) when the materials were analyzed by high-performance liquid chromatography (HPLC). Therefore, nixtamalization reduced both the measured amount of FB1 and the ceramide synthase inhibitory activity of masa and tortilla chips extracts. The results further suggest that the masa and tortilla chip extracts did not contain significant amounts of unknown fumonisins having ceramide synthase inhibitory activity. PMID:16760143

  16. Activation/Inhibition of mast cells by supra-optimal antigen concentrations.

    PubMed

    Huber, Michael

    2013-01-01

    Mast cells (MCs) are tissue resident cells of hemopoietic origin and are critically involved in allergic diseases. MCs bind IgE by means of their high-affinity receptor for IgE (FcεRI). The FcεRI belongs to a family of multi-chain immune recognition receptors and is activated by cross-linking in response to multivalent antigens (Ags)/allergens. Activation of the FcεRI results in immediate release of preformed granular substances (e.g. histamine, heparin, and proteases), generation of arachidonic acid metabolites, and production of pro-inflammatory cytokines. The FcεRI shows a remarkable, bell-shaped dose-response behavior with weak induction of effector responses at both low and high (so-called supra-optimal) Ag concentrations. This is significantly different from many other receptors, which reach a plateau phase in response to high ligand concentrations. To explain this unusual dose-response behavior of the FcεRI, scientists in the past have drawn parallels to so-called precipitin curves resulting from titration of Ag against a fixed concentration of antibody (Ab) in solution (a.k.a. Heidelberger curves). Thus, for high, supra-optimal Ag concentrations one could assume that every IgE-bound FcεRI formed a monovalent complex with "its own Ag", thus resulting in marginal induction of effector functions due to absence of receptor cross-linking. However, this was never proven to be the case. More recently, careful studies of FcεRI activation and signaling events in MCs in response to supra-optimal Ag concentrations have suggested a molecular explanation for the descending part of this bell-shaped curve. It is obvious now that extensive FcεRI/IgE/Ag clusters are formed and inhibitory molecules and signalosomes are engaged in response to supra-optimal cross-linking (amongst them the Src family kinase Lyn and the inositol-5'-phosphatase SHIP1) and they actively down-regulate MC effector responses. Thus, the analysis of MC signaling triggered by supra

  17. Single-molecule imaging at high fluorophore concentrations by local activation of dye.

    PubMed

    Geertsema, Hylkje J; Schulte, Aartje C; Spenkelink, Lisanne M; McGrath, William J; Morrone, Seamus R; Sohn, Jungsan; Mangel, Walter F; Robinson, Andrew; van Oijen, Antoine M

    2015-02-17

    Single-molecule fluorescence microscopy is a powerful tool for observing biomolecular interactions with high spatial and temporal resolution. Detecting fluorescent signals from individual labeled proteins above high levels of background fluorescence remains challenging, however. For this reason, the concentrations of labeled proteins in in vitro assays are often kept low compared to their in vivo concentrations. Here, we present a new fluorescence imaging technique by which single fluorescent molecules can be observed in real time at high, physiologically relevant concentrations. The technique requires a protein and its macromolecular substrate to be labeled each with a different fluorophore. Making use of short-distance energy-transfer mechanisms, only the fluorescence from those proteins that bind to their substrate is activated. This approach is demonstrated by labeling a DNA substrate with an intercalating stain, exciting the stain, and using energy transfer from the stain to activate the fluorescence of only those labeled DNA-binding proteins bound to the DNA. Such an experimental design allowed us to observe the sequence-independent interaction of Cy5-labeled interferon-inducible protein 16 with DNA and the sliding via one-dimensional diffusion of Cy5-labeled adenovirus protease on DNA in the presence of a background of hundreds of nanomolar Cy5 fluorophore. PMID:25692599

  18. Measurements of 222Rn activity concentration in domestic water sources in Penang, northern peninsular Malaysia.

    PubMed

    Muhammad, B G; Jaafar, M S; Azhar, A R; Akpa, T C

    2012-04-01

    Measurements of (222)Rn activity concentration were carried out in 39 samples collected from the domestic and drinking water sources used in the island and mainland of Penang, northern peninsular, Malaysia. The measured activity concentrations ranged from 7.49 to 26.25 Bq l(-1), 0.49 to 9.72 Bq l(-1) and 0.58 to 2.54 Bq l(-1) in the raw, treated and bottled water samples collected, respectively. This indicated relatively high radon concentrations compared with that from other parts of the world, which still falls below the WHO recommended treatment level of 100 Bq l(-1). From this data, the age-dependent associated committed effective doses due to the ingestion of (222)Rn as a consequence of direct consumption of drinking water were calculated. The committed effective doses from (222)Rn resulting from 1 y's consumption of these water were estimated to range from 0.003 to 0.048, 0.001 to 0.018 and 0.002 to 0.023 mSv y(-1), for age groups 0-1, 2-16 and >16 y, respectively. PMID:21642647

  19. Variability in Saponin Content, Cancer Antiproliferative Activity and Physicochemical Properties of Concentrated Agave Sap.

    PubMed

    Santos-Zea, Liliana; Rosas-Pérez, Aratza Mireya; Leal-Díaz, Ana María; Gutiérrez-Uribe, Janet A

    2016-08-01

    Concentrated agave sap (CAS) has gained popularity as an unrefined sweetener. It is obtained by boiling "aguamiel" that contains phytochemicals with diverse bioactivities. Saponins have been the most widely studied agave phytochemicals due to their cancer antiproliferative effect but their concentration may vary due to maturity of the agave plant and collection site. In this study, 18 CAS samples produced in different states of Mexico were analyzed using multivariate methods to determine which physicochemical or phytochemical parameters were responsible for variation. Additionally, extracts with different saponin profiles were tested to determine possible correlations with antiproliferative activity. Total soluble solids, pH, and water activity were similar to those reported for other agave sweeteners. Antioxidant capacity of samples was correlated to browning index. Eleven steroidal saponins were found in CAS samples and they were the main source of variability. Magueyoside B, a kammogenin tetraglycoside, was the most abundant saponin in all samples. With respect to bioactivity, multivariate analysis indicated that magueyoside B and a gentrogenin tetraglycoside were compounds strongly related with bioactivity. CAS from Hidalgo, Puebla, and Veracruz had higher concentration of magueyoside B than from the other kamogenin tetraglycoside found in the samples from other Mexican states. These results could be used as a first approach to characterize and standardize CAS to validate the potential health benefits derived from its consumption. PMID:27376349

  20. Single-molecule imaging at high fluorophore concentrations by local activation of dye

    SciTech Connect

    Geertsema, Hylkje J.; Mangel, Walter F.; Schulte, Aartje C.; Spenkelink, Lisanne M.; McGrath, William J.; Morrone, Seamus R.; Sohn, Jungsan; Robinson, Andrew; van Oijen, Antoine M.

    2015-02-17

    Single-molecule fluorescence microscopy is a powerful approach to observe biomolecular interactions with high spatial and temporal resolution. Detecting fluorescent signals from individual, labeled proteins above high levels of background fluorescence remains challenging, however. For this reason, the concentrations of labeled proteins in in vitro assays are often kept low compared to their in vivo concentrations. Here, we present a new fluorescence imaging technique by which single fluorescent molecules can be observed in real time at high, physiologically relevant concentrations. The technique requires a protein and its macromolecular substrate to be labeled each with a different fluorophore. Then, making use of short-distance energy-transfer mechanisms, the fluorescence from only those proteins bound to their substrate are selectively activated. This approach is demonstrated by labeling a DNA substrate with an intercalating stain, exciting the stain, and using energy transfer from the stain to activate the fluorescence of only those labeled DNA-binding proteins bound to the DNA. Such an experimental design allowed us to observe the sequence-independent interaction of Cy5-labeled interferon-inducible protein 16 (IFI16) with DNA and the sliding via one-dimensional diffusion of Cy5-labeled adenovirus protease (pVIc-AVP) on DNA in the presence of a background of hundreds of nM Cy5 fluorophore.

  1. Single-molecule imaging at high fluorophore concentrations by local activation of dye

    DOE PAGESBeta

    Geertsema, Hylkje J.; Mangel, Walter F.; Schulte, Aartje C.; Spenkelink, Lisanne M.; McGrath, William J.; Morrone, Seamus R.; Sohn, Jungsan; Robinson, Andrew; van Oijen, Antoine M.

    2015-02-17

    Single-molecule fluorescence microscopy is a powerful approach to observe biomolecular interactions with high spatial and temporal resolution. Detecting fluorescent signals from individual, labeled proteins above high levels of background fluorescence remains challenging, however. For this reason, the concentrations of labeled proteins in in vitro assays are often kept low compared to their in vivo concentrations. Here, we present a new fluorescence imaging technique by which single fluorescent molecules can be observed in real time at high, physiologically relevant concentrations. The technique requires a protein and its macromolecular substrate to be labeled each with a different fluorophore. Then, making use ofmore » short-distance energy-transfer mechanisms, the fluorescence from only those proteins bound to their substrate are selectively activated. This approach is demonstrated by labeling a DNA substrate with an intercalating stain, exciting the stain, and using energy transfer from the stain to activate the fluorescence of only those labeled DNA-binding proteins bound to the DNA. Such an experimental design allowed us to observe the sequence-independent interaction of Cy5-labeled interferon-inducible protein 16 (IFI16) with DNA and the sliding via one-dimensional diffusion of Cy5-labeled adenovirus protease (pVIc-AVP) on DNA in the presence of a background of hundreds of nM Cy5 fluorophore.« less

  2. Single-Molecule Imaging at High Fluorophore Concentrations by Local Activation of Dye

    PubMed Central

    Geertsema, Hylkje J.; Schulte, Aartje C.; Spenkelink, Lisanne M.; McGrath, William J.; Morrone, Seamus R.; Sohn, Jungsan; Mangel, Walter F.; Robinson, Andrew; van Oijen, Antoine M.

    2015-01-01

    Single-molecule fluorescence microscopy is a powerful tool for observing biomolecular interactions with high spatial and temporal resolution. Detecting fluorescent signals from individual labeled proteins above high levels of background fluorescence remains challenging, however. For this reason, the concentrations of labeled proteins in in vitro assays are often kept low compared to their in vivo concentrations. Here, we present a new fluorescence imaging technique by which single fluorescent molecules can be observed in real time at high, physiologically relevant concentrations. The technique requires a protein and its macromolecular substrate to be labeled each with a different fluorophore. Making use of short-distance energy-transfer mechanisms, only the fluorescence from those proteins that bind to their substrate is activated. This approach is demonstrated by labeling a DNA substrate with an intercalating stain, exciting the stain, and using energy transfer from the stain to activate the fluorescence of only those labeled DNA-binding proteins bound to the DNA. Such an experimental design allowed us to observe the sequence-independent interaction of Cy5-labeled interferon-inducible protein 16 with DNA and the sliding via one-dimensional diffusion of Cy5-labeled adenovirus protease on DNA in the presence of a background of hundreds of nanomolar Cy5 fluorophore. PMID:25692599

  3. Breast Milk Concentration of Rubidium in Lactating Mothers by Instrumental Neutron Activation Analysis Method

    PubMed Central

    Khatami, Seyedeh-Fatemeh; Parvaresh, Pouya; Parvaresh, Parviz; Madani Kouchak, Sara Sadat; Khorsandi, Jamshid

    2014-01-01

    Objective: Relatively little is known about the trace elements content of human milk from different countries. This has not been fully investigated especially among Iranian women. This study aimed to assess the concentration of Rubidium (Rb) as a poisonous trace element in transitional breast milk of lactating mothers living in Mashhad. Methods: Forty nursing mothers in early lactation 3 days to 15 days postpartum, free from any medical disorder and/or medication were randomly selected. We have applied Instrumental Neutron Activation Analysis (INAA) to assess the long-lived isotope trace element Rb in transitional milk of these economically moderate 18–39 year old Iranian women. Findings: The average concentration level of Rb was 32.176 ppm dry weight (min 8.660, max 107.210 ppm). No significant correlation was observed between Rb concentration and maternal weight and age (P=0.06, P=0.05 respectively) and newborns’ weight, age and sex (P=0.07, P=0.2, P=0.2 respectively). Conclusion: Although the Rubidium concentration found in this study is among the highest reported in the literature, it could not be compared to other studies because of differences in analytical performance, state of lactation, and unavailable reference ranges, so this finding needs further investigations. PMID:26019773

  4. Inhibitory effects of pomegranate concentrated solution on the activities of hyaluronidase, tyrosinase, and metalloproteinase.

    PubMed

    Kang, Su Jin; Choi, Beom Rak; Kim, Seung Hee; Yi, Hae Yeon; Park, Hye Rim; Park, Soo Jin; Song, Chang Hyun; Park, Ji Ha; Lee, Young Joon; Kwang, Sae

    2015-01-01

    Synopsis Botanical antioxidants have attracted much attention as useful preventatives of skin damage. Pomegranate is consumed throughout the world for its beneficial health effects, including its antioxidant and anti-inflammatory activities. We investigated whether pomegranate concentrated solution (PCS) could serve as a potential functional cosmetic ingredient that exerts a skin-whitening effect and antiwrinkle activity. To investigate the moisturizing effect of PCS, hyaluronidase activity was examined in human keratinocytes (HaCaT). Elastase and procollagenase activities were assessed in normal human primary dermal fibroblast-neonatal (HDF-N) cells to determine their antiwrinkle effects. Metalloproteinase 1 (MMP-1) activity was also assessed following ultraviolet A (UVA) irradiation. Whitening effects were measured by a tyrosinase inhibition assay and melanin formation test in mouse melanocytes (Melan-a). In addition, histopathological analysis was performed to determine the number of microfolds formed on the epithelial surface, mean epithelial thickness, mean number of inflammatory cells infiltrating the dermis, and collagen fiber-occupied regions within the dermis. Hyaluronan synthesis was significantly increased by PCS in HaCaT cells, while procollagenase and elastase activities were decreased in HDF-N cells. A significant decrease in UVA-induced MMP-1 activity was also observed in PCS-treated HDF-N cells, compared with UVA-exposed cells. PCS effectively reduced melanin production and mushroom tyrosinase activity in Melan-a cells. Moreover, UVB-induced histopathological dermal sclerosis and inflammatory signs were significantly attenuated in PCS-administered mice compared with UVB-exposed mice. Conclusions: Our results suggest that PCS prevents signs of aging, including those related to photoaging. These effects are associated with enhanced hyaluronan synthesis, as well as suppressed elastase, collagenase, MMP-1, and tyrosinase activities and melanin

  5. High Fetal Estrogen Concentrations: Correlation with Increased Adult Sexual Activity and Decreased Aggression in Male Mice

    NASA Astrophysics Data System (ADS)

    Vom Saal, Frederick S.; Grant, William M.; McMullen, Carol W.; Laves, Kurt S.

    1983-06-01

    In the house mouse (Mus musculus), fetuses may develop in utero next to siblings of the same or opposite sex. The amniotic fluid of the female fetuses contains higher concentrations of estradiol than that of male fetuses. Male fetuses that developed in utero between female fetuses had higher concentrations of estradiol in their amniotic fluid than males that were located between other male fetusesw during intrauterine development. They were also more sexually active as adults, less aggressive, and had smaller seminal vesicles than males that had developed between other male fetuses in utero. These findings raise the possibility that during fetal life circulating estrogens may interact with circulating androgens both in regulating the development of sex differences between males and females and in producing variation in phenotype among males and among females.

  6. Measurement of the terrestrial and anthropogenic radionuclide concentrations in Bafra Kizilirmak delta (bird sanctuary) in Turkey.

    PubMed

    Mutuk, Halil; Gümüs, Hasan; Turhan, Seref

    2014-01-01

    In this study, the activity concentrations of terrestrial and anthropogenic radionuclides in the soil samples collected from Bafra Kızılırmak Delta were measured by using gamma spectrometry with an NaI(Tl) detector. The average values of activity concentrations of (238)U, (232)Th and (40)K were found to be 37.2±2.8, 33.7±3.1 and 413.0±59.8 Bq kg(-1), respectively. (137)Cs was also measured in some samples. It has a mean value of 13.8±1.0 Bq kg(-1). From the activity concentrations, the absorbed gamma dose rates in outdoor and the corresponding annual effective dose rates and external hazard index (Hex) were estimated. PMID:24106331

  7. Serum Malondialdehyde Concentration and Glutathione Peroxidase Activity in a Longitudinal Study of Gestational Diabetes

    PubMed Central

    Miranda, María; Muriach, María; Romero, Francisco J.; Villar, Vincent M.

    2016-01-01

    Aims The main goal of this study was to evaluate the presence of oxidative damage and to quantify its level in gestational diabetes. Methods Thirty-six healthy women and thirty-six women with gestational diabetes were studied in the three trimesters of pregnancy regarding their levels of oxidative stress markers. These women were diagnosed with diabetes in the second trimester of pregnancy. Blood glucose levels after 100g glucose tolerance test were higher than 190, 165 or 145 mg/dl, 1, 2 or 3 hours after glucose intake. Results The group of women with gestational diabetes had higher serum malondialdehyde levels, with significant differences between groups in the first and second trimester. The mean values of serum glutathione peroxidase activity in the diabetic women were significantly lower in the first trimester. In the group of women with gestational diabetes there was a negative linear correlation between serum malondialdehyde concentration and glutathione peroxidase activity in the second and third trimester. Conclusions In this observational and longitudinal study in pregnant women, the alterations attributable to oxidative stress were present before the biochemical detection of the HbA1c increase. Usual recommendations once GD is detected (adequate metabolic control, as well as any other normally proposed to these patients) lowered the concentration of malondialdehyde at the end of pregnancy to the same levels of the healthy controls. Serum glutathione peroxidase activity in women with gestational diabetes increased during the gestational period. PMID:27228087

  8. Effect of an Activated Platelet Concentrate on Differentiated Cells Involved in Tissue Healing.

    PubMed

    Brini, Anna T; Ceci, Caterina; Taschieri, Silvio; Niada, Stefania; Lolato, Alessandra; Giannasi, Chiara; Mortellaro, Carmen; Del Fabbro, Massimo

    2016-05-01

    Tissue healing is a complex process involving several players such as cells and growth factors released from platelets upon activation. Today, platelet concentrates (PCs) are used in many different medical fields including oral, orthopaedic, and reconstructive surgery since they allow growth factors delivery to the injured site, aiming at enhancing tissue regeneration. The purpose of this in vitro study was to evaluate the effect of the acellular plasma of an activated platelet concentrate obtained using a manual protocol, on the proliferation, and biological activity of differentiated cells involved in tissue healing. Human osteoblasts and dermal fibroblasts were grown in serum-free medium supplemented with PC derived from several donors. Human osteoblast and human dermal fibroblast proliferation was assessed by MTT test after 7 days and cells were count up to 12-day incubation. Human osteoblast osteo-differentiation was tested after 7 and 14-day incubation by alkaline phosphatase assay. The addition of PC to the culture medium caused an increased proliferation with respect to cells grown in standard condition. The results of the present study suggest that PC supports the proliferation of terminally differentiated cells involved in wound healing and tissue regeneration, confirming its beneficial clinical application in regenerative therapies. PMID:27054419

  9. Lithium ions in nanomolar concentration modulate glycine-activated chloride current in rat hippocampal neurons.

    PubMed

    Solntseva, E I; Bukanova, J V; Kondratenko, R V; Skrebitsky, V G

    2016-03-01

    Lithium salts are successfully used to treat bipolar disorder. At the same time, according to recent data lithium may be considered as a candidate medication for the treatment of neurodegenerative disorders. The mechanisms of therapeutic action of lithium have not been fully elucidated. In particular, in the literature there are no data on the effect of lithium on the glycine receptors. In the present study we investigated the effect of Li(+) on glycine-activated chloride current (IGly) in rat isolated pyramidal hippocampal neurons using patch-clamp technique. The effects of Li(+) were studied with two glycine concentrations: 100 μM (EC50) and 500 μM (nearly saturating). Li(+) was applied to the cell in two ways: first, by 600 ms co-application with glycine through micropipette (short application), and, second, by addition to an extracellular perfusate for 10 min (longer application). Li(+) was used in the range of concentrations of 1 nM-1 mM. Short application of Li(+) caused two effects: (1) an acceleration of desensitization (a decrease in the time of half-decay, or "τ") of IGly induced by both 100 μM and 500 μM glycine, and (2) a reduction of the peak amplitude of the IGly, induced by 100 μM, but not by 500 μM glycine. Both effects were not voltage-dependent. Dose-response curves for both effects were N-shaped with two maximums at 100 nM and 1 mM of Li(+) and a minimum at 1 μM of Li(+). This complex form of dose-response may indicate that the process activated by high concentrations of lithium inhibits the process that is sensitive to low concentrations of lithium. Longer application of Li(+)caused similar effects, but in this case 1 μM lithium was effective and the dose-effect curves were not N-shaped. The inhibitory effect of lithium ions on glycine-activated current suggests that lithium in low concentrations is able to modulate tonic inhibition in the hippocampus. This important property of lithium should be considered when using this drug as a

  10. Arsenic Adsorption Equilibrium Concentration and Adsorption Rate of Activated Carbon Coated with Ferric-Aluminum Hydroxides

    NASA Astrophysics Data System (ADS)

    Zhang, M.; Sugita, H.; Oguma, T.; Hara, J.; Takahashi, S.

    2015-12-01

    In some areas of developing countries, ground or well water contaminated with arsenic has been reluctantly used as drinking water. It is highly desirable that effective and inexpensive arsenic removal agents should be developed and provided to reduce the potential health risk. Previous studies demonstrated that activated carbon coated with ferric-aluminum hydroxides (Fe-Al-C) has high adsorptive potential for removal of arsenic. In this study, a series of experiments using Fe-Al-C were carried to discuss adsorption equilibrium time, adsorption equilibrium concentration and adsorption rate of arsenic for Fe-Al-C. Fe-Al-C used in this study was provided by Astec Co., Ltd. Powder reagent of disodium hydrogen arsenate heptahydrate was dissolved into ion-exchanged water. The solution was then further diluted with ion-exchanged water to be 1 and 10 mg/L as arsenic concentration. The pH of the solution was adjusted to be around 7 by adding HCl and/or NaOH. The solution was used as artificial arsenic contaminated water in two types of experiments (arsenic adsorption equilibrium and arsenic adsorption rate tests). The results of the arsenic equilibrium tests were showed that a time period of about 3 days to reach apparent adsorption equilibrium for arsenic. The apparent adsorption equilibrium concentration and adsorbed amount of arsenic on Fe-Al-C adsorbent could be estimated by application of various adsorption isotherms, but the distribution coefficient of arsenic between solid and liquid varies with experimental conditions such as initial concentration of arsenic and addition concentration of adsorbent. An adsorption rate equation that takes into account the reduction in the number of effective adsorption sites on the adsorbent caused by the arsenic adsorption reaction was derived based on the data obtained from the arsenic adsorption rate tests.

  11. Intestinal morphology and enzymatic activity in newly weaned pigs fed contrasting fiber concentrations and fiber properties.

    PubMed

    Hedemann, M S; Eskildsen, M; Laerke, H N; Pedersen, C; Lindberg, J E; Laurinen, P; Knudsen, K E Bach

    2006-06-01

    The main objective of this study was to determine the effect of fiber source and concentration on morphological characteristics, mucin staining pattern, and mucosal enzyme activities in the gastrointestinal tract of pigs. The experiment included 50 pigs from 10 litters weaned at 4 wk of age (BW 8.6 +/- 1.4 kg) and divided into 5 treatment groups. Diets containing fiber of various physico-chemical properties and concentrations were formulated to contain 73, 104, or 145 g of dietary fiber/kg of DM. The diets were based on raw wheat and barley flours. Pectin and barley hulls, representing soluble and insoluble fiber sources, respectively, were used to increase the fiber concentration. The pigs were fed the experimental diets for 9 d, and then the pigs were euthanized and the entire gastrointestinal tract was removed. Tissue samples were taken from the mid and distal small intestine and from the mid colon. Inclusion of pectin in the diets significantly decreased (P < 0.001) ADFI and ADG compared with pigs fed no pectin. The villi and the crypts were shorter in pigs fed pectin-containing diets, but the villous height/crypt depth ratio was unaltered. Pectin significantly decreased the area of mucins in the crypts of the small intestine, indicating that the pigs fed the pectin-containing diet would probably be more susceptible to pathogenic bacteria, although this cannot be separated from the impact on ADFI. The lectin-binding pattern of the intestinal mucosa was unaffected by diet. The activity of lactase and maltase was increased in pigs fed diets with high fiber content, whereas sucrase activity was increased in pigs fed the pectin-containing diets. The activity of the peptidases, aminopeptidase N and dipeptidylpeptidase IV, was increased when feeding high fiber diets, whereas the activity of gamma-glutamyl transpeptidase remained unaffected by the experimental diets. In conclusion, the reduced feed intake observed with the pectin-containing diets could explain the

  12. Effect of Yeast Probiotic on Growth, Antioxidant Enzyme Activities and Malondialdehyde Concentration of Broiler Chickens

    PubMed Central

    Aluwong, Tagang; Kawu, Mohammed; Raji, Moshood; Dzenda, Tavershima; Govwang, Felix; Sinkalu, Victor; Ayo, Joseph

    2013-01-01

    The aim of the study was to determine the effect of yeast probiotic on body weight, and the activities of anti-oxidant enzymes: superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), and malondialdehyde (MDA) concentration of broiler chickens. The experiment was carried out on hybrid Hubbard broiler chickens (n = 200). Two-hundred day-old chicks were randomly selected and distributed into four groups of 50 day-old chicks each: Control, C, and treatment groups comprising T1, T2 and T3 administered with 0.25 mL, 0.5 mL and 1.0 mL yeast probiotic, respectively. Chicks were fed a commercial starter diet for the first 28 days of age, followed by pelleted finisher diet from 29 to 42 days. Chickens in T1 had a significantly (p < 0.01) higher body weight at 4th week of age when compared with the control. SOD activity in all treatment groups was not significantly (p > 0.05) different when compared with the control. GPx activity was significantly (p < 0.01) higher in T1, when compared with the control. GPx activity in T2 was higher (p < 0.01) when compared with the control. There was no significant (p > 0.05) difference in MDA level in all the treatment groups. In conclusion, administering yeast probiotic supplement increased body weight and enhanced serum anti-oxidant enzyme activities of broiler chickens. PMID:26784468

  13. Melanin-concentrating hormone is necessary for olanzapine-inhibited locomotor activity in male mice.

    PubMed

    Chee, Melissa J S; Douris, Nicholas; Forrow, Avery B; Monnard, Arnaud; Lu, Shuangyu; Flaherty, Stephen E; Adams, Andrew C; Maratos-Flier, Eleftheria

    2015-10-01

    Olanzapine (OLZ), an atypical antipsychotic, can be effective in treating patients with restricting type anorexia nervosa who exercise excessively. Clinical improvements include weight gain and reduced pathological hyperactivity. However the neuronal populations and mechanisms underlying OLZ actions are not known. We studied the effects of OLZ on hyperactivity using male mice lacking the hypothalamic neuropeptide melanin-concentrating hormone (MCHKO) that are lean and hyperactive. We compared the in vivo effects of systemic or intra-accumbens nucleus (Acb) OLZ administration on locomotor activity in WT and MCHKO littermates. Acute systemic OLZ treatment in WT mice significantly reduced locomotor activity, an effect that is substantially attenuated in MCHKO mice. Furthermore, OLZ infusion directly into the Acb of WT mice reduced locomotor activity, but not in MCHKO mice. To identify contributing neuronal mechanisms, we assessed the effect of OLZ treatment on Acb synaptic transmission ex vivo and in vitro. Intraperitoneal OLZ treatment reduced Acb GABAergic activity in WT but not MCHKO neurons. This effect was also seen in vitro by applying OLZ to acute brain slices. OLZ reduced the frequency and amplitude of GABAergic activity that was more robust in WT than MCHKO Acb. These findings indicate that OLZ reduced Acb GABAergic transmission and that MCH is necessary for the hypolocomotor effects of OLZ. PMID:26092201

  14. Activated charcoal filter counting for radioiodine effluent concentration determination in protein iodinations.

    PubMed

    Button, T M; Hamilton, R G

    1982-12-01

    Regulatory agencies have recently placed emphasis upon quantification of 125I released to the environment during protein iodinations at radioiodination facilities. This necessitates air sampling in order to determine the concentration of 125I in the effluent. Air sample trapping mechanisms generally employed are activated charcoal filters. Difficulty arises in quantifying the activity of 125I trapped because of the attenuation of the 125I decay photons by the charcoal. Evaluation of the activity incident upon commercially available filters using a scintillation detector and large detector source separation is considered here. It is demonstrated that the activity in the filter may be treated as an exponential distribution within an attentuating matrix. This treatment essentially adds a constant correction factor to the counting efficiency of a given geometry for a filter-affluent flow rate combination. Finally, it is shown that an approximation assuming a uniform distribution of activity produces a large error in correction factor to the counting efficiency for the filters examined. PMID:7152949

  15. Barley chloroplast glutamine synthetase activity is not affected by CO sub 2 -concentration

    SciTech Connect

    Avila, C.; Forde, B.; Wallsgrove, R. )

    1990-05-01

    It has been reported that when photorespiration is suppressed by raising the concentration of CO{sub 2}, the expression of the chloroplast glutamine synthetase (GS2) gene in pea leaves is reduced (Plant Cell, 1, 241). We have examined this effect in barley (Hordeum vulgare), and confirm that plants grown continuously in 0.8% CO{sub 2}, or transferred to such conditions after growth in air, appear to have a reduced GS2 mRNA abundance. However, we were unable to detect any significant difference in the extractable GS2 activity, or any change in amount of GS2 protein (judged by Western blots). Whatever controls are operating on gS2 mRNA expression in response to changes is external CO{sub 2}, they do not affect the activity or amount of the enzyme in barley.

  16. Preparation and Characterization of Nanocomposites from Whey Protein Concentrate Activated with Lycopene.

    PubMed

    Pereira, Rafaela Corrêa; de Deus Souza Carneiro, João; Borges, Soraia Vilela; Assis, Odílio Benedito Garrido; Alvarenga, Gabriela Lara

    2016-03-01

    The production and characterization of nanocomposites based on whey protein concentrate (WPC) and montmorilonite (MMT) incorporated with lycopene as a functional substance is presented and discussed as an alternative biomaterial for potential uses in foodstuff applications. A full factorial design with varying levels of MMT (0% and 2% in w/w) and lycopene (0%, 6%, and 12% in w/w) was used. Color, light transmission, film transparency, moisture, density, solubility, water vapor permeability, and antioxidant activity of the resulting materials were evaluated. Results indicated that lycopene and MMT nanoparticles were successfully included in WPC films using the casting/evaporation method. Inclusion of 2% w/w of MMT in the polymeric matrix significantly improved barrier property against water vapor. Lycopene, besides its good red coloring ability, provided to the films antioxidant activity and UV-vis light protection. These findings open a new perspective for the use of materials for bioactive packaging applications. PMID:26814439

  17. A novel method for measuring aromatase activity in tissue samples by determining estradiol concentrations.

    PubMed

    Tinwell, H; Rascle, J B; Colombel, S; Al Khansa, I; Freyberger, A; Bars, R

    2011-07-01

    Increasing scrutiny of endocrine disrupters has led to changes to European pesticide and biocide legislation and to the introduction of the Endocrine Disrupter Screening Program by the US EPA. One element of endocrine disrupter identification is to determine its effects on aromatase, but most available assays are limited as they depend on tritiated water production to indicate enzyme activity. Whilst acceptable for determining aromatase effects using a cell-free approach, this method is unreliable for cell or tissue-based investigations as other cytochrome P-450 isoenzyme activities can similarly produce tritiated water and consequently confound interpretation of the aromatase data. To address this lack of specificity an assay directly measuring the final estrogen product by incubating rat tissue protein with testosterone and measuring the resultant estradiol concentration was developed. Using this approach we demonstrated marked increases in enzyme activity in pregnant rat ovary samples and dose-related inhibitions when incubating non-pregnant rat ovary samples with known aromatase inhibitors. Hepatic aromatase activity was investigated using our method and by tritiated water production with microsomes from rats dosed with the antiandrogen 1,1-dichloro-2,2-bis(4 chlorophenyl)ethane. Additional cytochrome P-450s were also measured. Treatment-related increased tritiated water production and general hepatic enzyme activity were recorded but estradiol was not increased, indicating that the increased tritiated water was due to general enzyme activity and not aromatase activity. A simple and specific method has been developed that can detect aromatase inhibition and induction, which when applied to tissue samples, provides a means of generating relevant animal data concerning chemical effects on the aromatase enzyme. PMID:21259292

  18. Effect of exo-polysaccharide concentration in the rheological properties and settling ability of activated sludge.

    PubMed

    Akkache, S; Seyssiecq, I; Roche, N

    2013-01-01

    The non-Newtonian properties of activated sludge (AS) suspension lead to transfer limitations (oxygen, substrate...) and operation difficulties in Waste Water Treatment Plants (WWTP). The current approach involves assuming the sludge behaves like water on a rheological point of view, and then oversizing pumping and aeration devices, which represent over 60% of the operating cost in WWTP. The objective of this work is to understand the effect of bioflocculation on the rheological properties and the settling ability of AS suspensions, by means of variations in concentration of exo-cellular polysaccharides. Experiments have been conducted in a 20 L laboratory scale bioreactor at a constant retention time of 20 days and with a total suspended solid concentration between 15 and 20 g L(-1). The bioreactor was fed with a synthetic substrate at a constant mass loading rate of 0.3 kg(DCO) kg(-1)(TSS) d(-1). Our results show that increasing the exo-polysaccharide (EPS) concentration from 10 to 80 mg g(-1)(TSS) leads to an increase in shear-thinning properties of AS. An improvement of the settling ability is also obtained, at least when the EPSs increase from 10 to 45 mg g(-1)(TSS). Above 45 mg g(-1)(TSS) of adsorbed polysaccharides, the settling ability seems to decrease again. PMID:24617058

  19. Concentrations and activity ratios of uranium isotopes in groundwater from Donana National Park, South of Spain

    SciTech Connect

    Bolivar, J. P.; Olias, M.; Gonzalez-Garcia, F.; Garcia-Tenorio, R.

    2008-08-07

    The levels and distribution of natural radionuclides in groundwaters from the unconfined Almonte-Marismas aquifer, upon which Donana National Park is located, have been analysed. Most sampled points were multiple piezometers trying to study the vertical distribution of the hydrogeochemical characteristics in the aquifer. Temperature, pH, electrical conductivity, dissolved oxygen and redox potential were determined in the field. A large number of parameters, physico-chemical properties, major and minor ions, trace elements and natural radionuclides (U-isotopes, Th-isotopes, Ra-isotopes and {sup 210}Po), were also analysed. In the southern zone, where aeolian sands crop out, water composition is of the sodium chloride type, and the lower U-isotopes concentrations have been obtained. As water circulates through the aquifer, bicarbonate and calcium concentrations increase slightly, and higher radionuclides concentrations were measured. Finally, we have demonstrated that {sup 234}U/{sup 238}U activity ratios can be used as markers of the type of groundwater and bedrock, as it has been the case for old waters with marine origin confined by a marsh in the south-east part of aquifer.

  20. High Concentrations of Organic Contaminants in Air from Ship Breaking Activities in Chittagong, Bangladesh.

    PubMed

    Nøst, Therese H; Halse, Anne K; Randall, Scott; Borgen, Anders R; Schlabach, Martin; Paul, Alak; Rahman, Atiqur; Breivik, Knut

    2015-10-01

    The beaches on the coast of Chittagong in Bangladesh are one of the most intense ship breaking areas in the world. The aim of the study was to measure the concentrations of organic contaminants in the air in the city of Chittagong, including the surrounding ship breaking areas using passive air samplers (N = 25). The compounds detected in the highest amounts were the polycyclic aromatic hydrocarbons (PAHs) and short-chain chlorinated paraffins (SCCPs), whereas dichlorodiphenyltrichloroethanes (DDTs), hexachlorobenzene (HCB), and polychlorinated biphenyls (PCBs) were several orders of magnitude lower in comparison. PCBs, PAHs, and HCB were highest at sites near the ship breaking activities, whereas DDTs and SCCPs were higher in the urban areas. Ship breaking activities likely act as atmospheric emission sources of PCBs, PAHs, and HCB, thus adding to the international emphasis on responsible recycling of ships. Concentrations of PAHs, PCBs, DDTs, HCB, and SCCPs in ambient air in Chittagong are high in comparison to those found in similar studies performed in other parts of Asia. Estimated toxic equivalent quotients indicate elevated human health risks caused by inhalation of PAHs at most sites. PMID:26351879

  1. Nutritional significance of a rice bran concentrate with trypsin inhibitor activity.

    PubMed

    Maki, Z; Tashiro, M

    1983-06-01

    A rice bran protein concentrate (RBPC) was prepared from de-fatted rice bran by extraction with a 1% sodium chloride solution and by acetone-precipitation. This protein concentrate contained 45% protein, which was as good as casein in terms of protein quality being judged from the results of amino acid analysis. On the other hand, RBPC possessed the trypsin inhibitor activity corresponding to the complete inhibition of about 6 mg of bovine trypsin per 1 g of dry material. The activity was, however, completely destroyed by autoclaving RBPC for 30 min at 121 degrees C. In vitro digestion tests showed that RBPC was easily digested by pepsin but was resistant to the attack by trypsin, compared with autoclaved RBPC. Concerning in vivo digestion, however, there was no significant difference in apparent nitrogen digestibility between RBPC and the heated RBPC. In growth experiments with weanling rats fed a 10% level of protein diet, growth depression and the tendency of slight pancreatic hypertrophy were observed in rats receiving a RBPC diet. It is presumed that one of the reasons which explains these phenomena is the presence of trypsin inhibitor in RBPC. PMID:6619992

  2. RNA Remodeling Activity of DEAD Box Proteins Tuned by Protein Concentration, RNA Length, and ATP.

    PubMed

    Kim, Younghoon; Myong, Sua

    2016-09-01

    DEAD box RNA helicases play central roles in RNP biogenesis. We reported earlier that LAF-1, a DEAD box RNA helicase in C. elegans, dynamically interacts with RNA and that the interaction likely contributes to the fluidity of RNP droplets. Here we investigate the molecular basis of the interaction of RNA with LAF-1 and its human homolog, DDX3X. We show that both LAF-1 and DDX3X, at low concentrations, are monomers that induce tight compaction of single-stranded RNA. At high concentrations, the proteins are multimeric and dynamically interact with RNA in an RNA length-dependent manner. The dynamic LAF-1-RNA interaction stimulates RNA annealing activity. ATP adversely affects the RNA remodeling ability of LAF-1 by suppressing the affinity, dynamics, and annealing activity of LAF-1, suggesting that ATP may promote disassembly of the RNP complex. Based on our results, we postulate a plausible molecular mechanism underlying the dynamic equilibrium of the LAF-1 RNP complex. PMID:27546789

  3. Detection of enteric viruses in activated sludge by feasible concentration methods

    PubMed Central

    Prado, Tatiana; Gaspar, Ana Maria Coimbra; Miagostovich, Marize Pereira

    2014-01-01

    Human enteric viruses are responsible to cause several diseases, including gastroenteritis and hepatitis, and can be present in high amounts in sewage sludge. This study compared virus recovery efficiency of two feasible concentration methods used for detecting human adenovirus (HAdV), rotavirus species A (RV-A), norovirus genogroup II (NoV GII) and hepatitis A virus (HAV) in sewage sludge from an activated sludge process. Twelve sewage sludge samples were collected bi-monthly from January to July, 2011. Ultracentrifugation was compared with a simplified protocol based on beef extract elution for recovering enteric viruses. Viruses were quantified by quantitative real-time PCR assays and virus recovery efficiency and limits of detection were determined. Methods showed mean recovery rates lower than 7.5%, presenting critical limits of detection (higher than 102 – 103 genome copies - GC L−1 for all viruses analyzed). Nevertheless, HAdV were detected in 90% of the analyzed sewage sludge samples (range: 1.8 × 104 to 1.1 × 105 GC L−1), followed by RV-A and NoV (both in 50%) and HAV (8%). Results suggesting that activated sludge is contaminated with high viral loads and HAdV are widely disseminated in these samples. The low virus recovery rates achieved, especially for HAV, indicate that other feasible concentration methods could be developed to improve virus recovery efficiency in these environmental matrices. PMID:24948954

  4. Effects of increasing size and changing europium activator concentration in KCaI3 scintillator crystals

    NASA Astrophysics Data System (ADS)

    Lindsey, Adam C.; Zhuravleva, Mariya; Wu, Yuntao; Stand, Luis; Loyd, Matthew; Gokhale, Sasmit; Koschan, Merry; Melcher, Charles L.

    2016-09-01

    KCaI3:Eu crystals have been identified as very promising for use in spectroscopic detector applications related to nuclear nonproliferation and domestic security efforts. Initial studies have shown for small crystals a few mm3 in size with 3% europium dopant concentration, a high light yield of >70,000 ph/MeV and energy resolution of ≈3% at 662 keV is attainable which is comparable with the highest performance scintillators discovered. In this work, single crystals of KCaI3 with a range of Eu2+ doping between 0 and 5 at% substituting for Ca2+ were grown at 22 mm diameter and their performance for gamma-ray spectroscopy studied. Comparisons among crystals approximately Ø22 mm×22 mm (8.4 cm3 or ≈0.5 in3) provide a more accurate understanding of how scintillation performance changes with Eu doping and increased crystal size. KCaI3 in the undoped form is shown to be a highly efficient intrinsic scintillator with a defect-related emission at 404 nm which coexists with the Eu2+ 5d-4f emission in low dopant concentrations and is completely re-absorbed in more heavily doped crystals. For larger crystals, effects from self-absorption due to Eu activation become more evident by a near doubling of decay time for 0.5 in3 crystals as the activator is increased from 0.5 to 5.0 at% Eu. Comparisons of pulse-height spectra obtained for Ø22 mm×22 mm cylinders with varying Eu concentration suggests best performance is achieved using lower Eu additions closer to 0.5-1.0 at%. Using a modified crystal packaging featuring an offset reflector geometry, 0.5 in3 crystals of KCaI3:Eu can attain under 4% energy resolution at 662 keV.

  5. Comparative hepatic cytochrome P450 activities and contaminant concentrations in caged carp and juvenile ducks

    SciTech Connect

    O`Keefe, P.; Gierthy, J.; Connor, S.; Bush, B.; Hong, C.S.; Wood, L.; Clayton, W.; Storm, R.

    1995-12-31

    Juvenile carp (Cyprinius carpio) weighing approx. 60 g were placed in cages located on the surface of sediments near an aluminum plant and an automobile parts plant in the Massena area of the St. Lawrence River. Fish were removed at weekly intervals over a 35 day exposure period and composited samples of liver tissue, cranial lipid, and fillet tissue were prepared for analysis of polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs). Liver tissue was also stored at {minus}80 C for determination of microsomal Cytochrome P450 activity using the aryl hydrocarbon hydroxylase (AHH) assay. A control exposure was carried out upstream at an uncontaminated site. Juvenile pre-flight ducks (mallards, gadwalls, wood ducks and common mergansers) were collected in the contaminated areas on the St. Lawrence and on the Hudson River two to three months after hatching. Control pre-flight mallards, wood ducks and common mergansers were collected from remote lakes in the Addirondack State Park. Samples of subcutaneous fat and liver tissue were removed for analysis as described above for the carp. There was a three fold increase in AHH activity in the carp liver tissue at the end of the 35 day exposure period and there was a similar increase it activity for the mallards, common mergansers and wood ducks compared to controls. For each species the enzyme activity increases will be compared to the contaminant concentrations.

  6. Evaluation of the radioactive Cs concentration in brown rice based on the K nutritional status of shoots.

    PubMed

    Sekimoto, Hitoshi; Yamada, Takashi; Hotsuki, Tomoe; Fujiwara, Toru; Mimura, Tetsuro; Matsuzaki, Akio

    2014-01-01

    The radioactive cesium ((134,137)Cs) concentration in brown rice is correlated with that in the straw/husk. The distribution of (134,137)Cs, resembles that of potassium (K), a homologous element of Cs, in the rice plant body. The relative isotopic abundance of (40)K is 0.0117 %; thus, 1 g K contains 30.4 Bq ⁴⁰K, and the mass of 4,000 Bq (40)K is 0.0154 g, indicating that the K concentration can be calculated from (40)K concentration. We examined if the radioactive Cs concentration in brown rice can be estimated from (40)K concentrations in straw, and especially might be predicted from the (40)K:(134,137)Cs ratio in straw. We determined the concentrations of (40)K and radioactive Cs in straw and brown rice, and found a strong correlated-equation (y = 72.922 x(-0.759); r = 0.907) between the radioactive Cs concentration in brown rice and the ⁴⁰K:(134,137)Cs ratio in straw. The estimated-radioactive Cs concentration in brown rice can be as much as double, depending on the K nutritional status changing the ⁴⁰K:(134,137)Cs ratio in straw. We herein propose a nutritional diagnosis that radioactive Cs concentrations in brown rice can be predicted from the ⁴⁰K:(134,137)Cs ratio in shoots. PMID:24338061

  7. High-Tc superconductivity at 40 K emerged in ultrathin FeSe electric-double-layer transistors

    NASA Astrophysics Data System (ADS)

    Junichi, Shiogai; Ito, Yukihiro; Mitsuhashi, Toshiki; Nojima, Tsutomu; Tsukazaki, Atsushi

    A few unit-cell (UC) FeSe films on SrTiO3 substrates have recently attracted much attentions owing to emergence of high temperature superconductivity (high-Tc) about 65 K compared to the bulk value of 8 K. Modulation of electronic structure, charge transfer from SrTiO3, and electron-phonon coupling between the film and substrate are proposed as possible origins for high-Tc. Although the in-situ scanning tunneling and photoemission spectroscopies have been intensively studied, systematic thickness, carrier density and substrate material dependences of electrical measurements have been limited so far. Here we report on high-Tc in FeSe films on SrTiO3 and MgO in electric-double-layer transistor (EDLT). Both the film thickness and electric field can be tuned by electrochemical etching and electrostatic doping in EDLT. The systematic thickness dependences reveal that the onset Tc of 40 K appears from around 10 nm to 1 UC under the electric field while the initial 18-nm-thick FeSe shows no high-Tc. Our results point out the importance of electron accumulation or electronic band modulation for high-Tc in FeSe rather than electron-phonon coupling.

  8. The preliminary results of the measurements of environmental levels of 40K and 137Cs in Venezuela

    NASA Astrophysics Data System (ADS)

    LaBrecque, J. J.; Rosales, P. A.; Carias, O.

    1992-02-01

    The study of the beta-particle radioactivity in air and 90Sr in rainwater collected at Instituto Venezolano de Investigaciones Cientificas, IVIC, that began in 1959 in conjunction with the U.S. Atomic Energy Commission was discontinued in 1963. But after the Chernobyl nuclear power plant accident in the USSR, work on the radioactive contamination in Venezuela has been renewed. Initially the measurement of 134Cs and 137Cs in imported foodstuffs, such as milk powders and meats were undertaken, and these have now been extended to measurements of environmental levels of 40K and 137Cs in soils, sea sediments and foodstuffs. The data present herein are the only readily available data on radioactive contamination in the environment in Venezuela since 1963. The measurements were performed with a simple Nal(Tl) detector and two single channel analyzers as well as with a 25% efficient hyper-pure germanium semiconductor coupled to a multichannel analyzer system. Finally, these results can be used as baseline values (environmental background) in case of a nuclear accident in the region, as well as to screen imported foodstuff which is suspected to be contaminated.

  9. Soil-to-root vegetable transfer factors for (226)Ra, (232)Th, (40)K, and (88)Y in Malaysia.

    PubMed

    Asaduzzaman, Kh; Khandaker, Mayeen Uddin; Amin, Y M; Bradley, D A; Mahat, R H; Nor, R M

    2014-09-01

    Soil-to-plant transfer factors (TFs) are of fundamental importance in assessing the environmental impact due to the presence of radioactivity in soil and agricultural crops. Tapioca and sweet potato, both root crops, are popular foodstuffs for a significant fraction of the Malaysian population, and result in intake of radionuclides. For the natural field conditions experienced in production of these foodstuffs, TFs and the annual effective dose were evaluated for the natural radionuclides (226)Ra, (232)Th, (40)K, and for the anthropogenic radionuclide (88)Y, the latter being a component of fallout. An experimental tapioca field was developed for study of the time dependence of plant uptake. For soil samples from all study locations other than the experimental field, it has been shown that these contain the artificial radionuclide (88)Y, although the uptake of (88)Y has only been observed in the roots of the plant Manihot esculenta (from which tapioca is derived) grown in mining soil. The estimated TFs for (226)Ra and (232)Th for tapioca and sweet potato are very much higher than that reported by the IAEA. For all study areas, the annual effective dose from ingestion of tapioca and sweet potato are estimated to be lower than the world average (290 μSv y(-1)). PMID:24814722

  10. Activity concentrations of environmental samples collected in Fukushima Prefecture immediately after the Fukushima nuclear accident

    PubMed Central

    Hosoda, Masahiro; Tokonami, Shinji; Tazoe, Hirofumi; Sorimachi, Atsuyuki; Monzen, Satoru; Osanai, Minoru; Akata, Naofumi; Kakiuchi, Hideki; Omori, Yasutaka; Ishikawa, Tetsuo; Sahoo, Sarata K.; Kovács, Tibor; Yamada, Masatoshi; Nakata, Akifumi; Yoshida, Mitsuaki; Yoshino, Hironori; Mariya, Yasushi; Kashiwakura, Ikuo

    2013-01-01

    Radionuclide concentrations in environmental samples such as surface soils, plants and water were evaluated by high purity germanium detector measurements. The contribution rate of short half-life radionuclides such as 132I to the exposure dose to residents was discussed from the measured values. The highest values of the 131I/137Cs activity ratio ranged from 49 to 70 in the environmental samples collected at Iwaki City which is located to the south of the F1-NPS. On the other hand, the 132I/131I activity ratio in the same environmental samples had the lowest values, ranging from 0.01 to 0.02. By assuming that the 132I/131I activity ratio in the atmosphere was equal to the ratio in the environmental samples, the percent contribution to the thyroid equivalent dose by 132I was estimated to be less than 2%. Moreover, the contribution to the thyroid exposure by 132I might be negligible if 132I contamination was restricted to Iwaki City. PMID:23887080

  11. Methanogenic activity inhibition by increasing the linear alkylbenzene sulfonate (LAS) concentration.

    PubMed

    Souza, Luiza F C; Florencio, Lourdinha; Gavazza, Savia; Kato, Mario T

    2016-07-01

    The effect of the initial concentration of linear alkylbenzene sulfonate (LAS) on specific methanogenic activity (SMA) was investigated in this work. Six anaerobic flasks reactors with 1 L of total volume were inoculated with anaerobic sludge (2 g VSS L(-1)). The reactors were assayed for 42 days, and fed with volatile fatty acids, nutrients, and LAS. The initial LAS concentrations were 0, 10, 30, 50, 75, and 100 mg L(-1) for the treatment flasks T1 (control), T2, T3, T4, T5, and T6, respectively. When compared with T1, T2 exhibited a 30% reduction in maximum SMA and total methane production (TMP). In treatment T3 through T6, the reductions were 44-97% (T3-T6) for SMA, and 30-90% (T3-T6) for TMP. Total LAS removal increased following the increase in the initial LAS concentration (from 36% at T1 to 76% at T6), primarily due to the high degree of sludge adsorption. LAS biodegradation also occurred (32% in all treatments), although this was most likely associated with the formation of non-methane intermediates. Greater removal by adsorption was observed in long-chain homologues, when compared to short-chain homologues (C13 > C10), whereas the opposite occurred for biodegradation (C10 > C13). The C13 homologue was adsorbed to a great extent (in mass) in T4, T5 and T6, and may also have inhibited methane formation in these treatments. PMID:27088975

  12. Concentration Effects of Polymer Electrolyte Membrane Degradation Products on Oxygen Reduction Activity for Three Platinum Catalysts

    DOE PAGESBeta

    Christ, J. M.; Neyerlin, K. C.; Richards, R.; Dinh, H. N.

    2014-10-04

    A rotating disk electrode (RDE) along with cyclic voltammetry (CV) and linear sweep voltammetry (LSV), were used to investigate the impact of two model compounds representing degradation products of Nafion and 3M perfluorinated sulfonic acid membranes on the electrochemical surface area (ECA) and oxygen reduction reaction (ORR) activity of polycrystalline Pt, nano-structured thin film (NSTF) Pt (3M), and Pt/Vulcan carbon (Pt/Vu) (TKK) electrodes. ORR kinetic currents (measured at 0.9 V and transport corrected) were found to decrease linearly with the log of concentration for both model compounds on all Pt surfaces studied. Ultimately, model compound adsorption effects on ECA weremore » more abstruse due to competitive organic anion adsorption on Pt surfaces superimposing with the hydrogen underpotential deposition (HUPD) region.« less

  13. Effects of oxygen concentration on the nitrifying activity of an aerobic hybrid granular sludge reactor.

    PubMed

    Filali, Ahlem; Bessiere, Yolaine; Sperandio, Mathieu

    2012-01-01

    The aim of the work was to quantify the influence of the simultaneous presence of flocs and granules in the nitrifying activity in a sequencing batch airlift reactor (SBAR). The nitrification rate and oxygen limitation of flocs, granules and hybrid sludge was investigated using respirometric assays at different dissolved oxygen concentrations. The spatial distribution of Ammonium Oxidizing Bacteria (AOB) and Nitrite Oxidizing Bacteria (NOB) was investigated using fluorescence in situ hybridization (FISH). Results showed that the nitrification rate was much less sensitive to oxygen limitation in systems containing a fraction of flocs than in pure granular sludge. Ammonium Oxidizing Bacteria (AOB) were found to be distributed in similar quantities in flocs and granules whereas the Nitrite Oxidizing Bacteria (NOB) were located preferentially in granules. This study showed that the presence of flocs with granules could increase the robustness of the process to transitory reductions of aeration. PMID:22233907

  14. Tuning the surface oxygen concentration of {111} surrounded ceria nanocrystals for enhanced photocatalytic activities

    NASA Astrophysics Data System (ADS)

    Younis, Adnan; Chu, Dewei; Kaneti, Yusuf Valentino; Li, Sean

    2015-12-01

    For oxide semiconductors, the morphology, particle size and oxygen vacancies are usually considered as key influential parameters for photocatalytic degradation of organic pollutants/dyes. It is widely accepted that cation doping not only modifies their phase and microstructures but also introduces variations in oxygen vacancy concentration. Herein, we report the fabrication of sub-10 nm sized pure and indium doped CeO2 nanocrystals (NCs) via a facile, green hydrothermal method for the investigation of photocatalytic activities. X-ray diffraction and transmission electron microscopy were employed to examine the crystal phase and morphology of the as-prepared nanocrystals. Raman and X-ray photoelectron spectroscopy techniques were implemented to investigate the presence and variations in oxygen vacancy concentration in un-doped and indium doped CeO2 nanocrystals. The photocatalytic activity results revealed that 10 at% doping is the optimal indium doping level to demonstrate superior dye removal efficiency (~40%) over un-doped and doped CeO2 NCs. Moreover, the 10% In-doped CeO2 nanocrystals expressed excellent cycling stability and superior photocatalytic performance toward other dye pollutants. Finally, on the basis of our findings, a possible photocatalytic mechanism in which indium doping can generate more surface oxygen vacancies in the ceria lattice which delay the electron-hole recombination rates, thus increasing the lifetime of electron-hole separation for enhanced photocatalytic performances was proposed.For oxide semiconductors, the morphology, particle size and oxygen vacancies are usually considered as key influential parameters for photocatalytic degradation of organic pollutants/dyes. It is widely accepted that cation doping not only modifies their phase and microstructures but also introduces variations in oxygen vacancy concentration. Herein, we report the fabrication of sub-10 nm sized pure and indium doped CeO2 nanocrystals (NCs) via a facile

  15. Management practices that concentrate visitor activities: Camping impact management at Isle Royale National Park, USA

    USGS Publications Warehouse

    Marion, J.L.; Farrell, T.A.

    2002-01-01

    This study assessed campsite conditions and the effectiveness of campsite impact management strategies at Isle Royale National Park, USA. Protocols for assessing indicators of vegetation and soil conditions were developed and applied to 156 campsites and 88 shelters within 36 backcountry campgrounds. The average site was 68 m2 and 83% of sites lost vegetation over areas less than 47 m2. Results reveal that management actions to spatially concentrate camping activities and reduce camping disturbance have been highly successful. Comparisons of disturbed area/overnight stay among other protected areas reinforces this assertion. These reductions in area of camping disturbance are attributed to a designated site camping policy, limitation on site numbers, construction of sites in sloping terrain, use of facilities, and an ongoing program of campsite maintenance. Such actions are most appropriate in higher use backcountry and wilderness settings.

  16. Management practices that concentrate visitor activities: camping impact management at Isle Royale National Park, USA.

    PubMed

    Marion, Jeffrey L; Farrell, Tracy A

    2002-10-01

    This study assessed campsite conditions and the effectiveness of campsite impact management strategies at Isle Royale National Park, USA. Protocols for assessing indicators of vegetation and soil conditions were developed and applied to 156 campsites and 88 shelters within 36 backcountry campgrounds. The average site was 68 m2 and 83% of sites lost vegetation over areas less than 47 m2. We believe that management actions implemented to spatially concentrate camping activities and reduce camping disturbance have been highly successful. Comparisons of disturbed area/overnight stay among other protected areas reinforces this assertion. These reductions in area of camping disturbance are attributed to a designated site camping policy, limitation on site numbers, construction of sites in sloping terrain, use of facilities, and an ongoing program of campsite maintenance. Such actions are most appropriate in higher use backcountry and wilderness settings. PMID:12418164

  17. Layered Double Hydroxide Nanoclusters: Aqueous, Concentrated, Stable, and Catalytically Active Colloids toward Green Chemistry.

    PubMed

    Tokudome, Yasuaki; Morimoto, Tsuyoshi; Tarutani, Naoki; Vaz, Pedro D; Nunes, Carla D; Prevot, Vanessa; Stenning, Gavin B G; Takahashi, Masahide

    2016-05-24

    Increasing attention has been dedicated to the development of nanomaterials rendering green and sustainable processes, which occur in benign aqueous reaction media. Herein, we demonstrate the synthesis of another family of green nanomaterials, layered double hydroxide (LDH) nanoclusters, which are concentrated (98.7 g/L in aqueous solvent), stably dispersed (transparent sol for >2 weeks), and catalytically active colloids of nano LDHs (isotropic shape with the size of 7.8 nm as determined by small-angle X-ray scattering). LDH nanoclusters are available as colloidal building blocks to give access to meso- and macroporous LDH materials. Proof-of-concept applications revealed that the LDH nanocluster works as a solid basic catalyst and is separable from solvents of catalytic reactions, confirming the nature of nanocatalysts. The present work closely investigates the unique physical and chemical features of this colloid, the formation mechanism, and the ability to act as basic nanocatalysts in benign aqueous reaction systems. PMID:27124717

  18. Concentration Effects of Polymer Electrolyte Membrane Degradation Products on Oxygen Reduction Activity for Three Platinum Catalysts

    SciTech Connect

    Christ, J. M.; Neyerlin, K. C.; Richards, R.; Dinh, H. N.

    2014-10-04

    A rotating disk electrode (RDE) along with cyclic voltammetry (CV) and linear sweep voltammetry (LSV), were used to investigate the impact of two model compounds representing degradation products of Nafion and 3M perfluorinated sulfonic acid membranes on the electrochemical surface area (ECA) and oxygen reduction reaction (ORR) activity of polycrystalline Pt, nano-structured thin film (NSTF) Pt (3M), and Pt/Vulcan carbon (Pt/Vu) (TKK) electrodes. ORR kinetic currents (measured at 0.9 V and transport corrected) were found to decrease linearly with the log of concentration for both model compounds on all Pt surfaces studied. Ultimately, model compound adsorption effects on ECA were more abstruse due to competitive organic anion adsorption on Pt surfaces superimposing with the hydrogen underpotential deposition (HUPD) region.

  19. 137Cs activity concentration in wild boar meat may still exceed the permitted levels

    NASA Astrophysics Data System (ADS)

    Rachubik, J.

    2012-04-01

    The radiocaesium activity concentration may still remain high in natural products such as game meat, wild mushrooms, and forest berries even more than two decades after the Chernobyl accident. The results of regular control studies of game meat conducted in Poland showed wild boars as the most contaminated game animals. It is well documented that some mushrooms, readily consumed by animals, show high ability to accumulate caesium radioisotopes. Bay bolete, one of the most wide-spread mushroom species in Poland, reveals a unique radiocaesium accumulation feature. Moreover, deer truffle, containing also particularly high levels of radiocaesium, could be another radionu-clide source for wild boars. Furthermore, animals consuming deer truffles could digest contaminated soil components. Among 94 wild boar meat samples analysed in 2008-2009, two exceeded the permitted level. Hence, some precautions should be taken in the population with an elevated intake of wild boar meat. Moreover, since each hunted wild boar is examined for the presence of Trichinella larvae, regular measurements of radiocaesium concentrations in these animals may be advisable for enhancing consumer safety.

  20. Enhanced antibacterial activity of bimetallic gold-silver core-shell nanoparticles at low silver concentration

    NASA Astrophysics Data System (ADS)

    Banerjee, Madhuchanda; Sharma, Shilpa; Chattopadhyay, Arun; Ghosh, Siddhartha Sankar

    2011-12-01

    Herein we report the development of bimetallic Au@Ag core-shell nanoparticles (NPs) where gold nanoparticles (Au NPs) served as the seeds for continuous deposition of silver atoms on its surface. The core-shell structure and morphology were examined by UV-Vis spectroscopy, transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis and X-ray diffraction (XRD). The core-shell NPs showed antibacterial activity against both Gram negative (Escherichia coli and Pseudomonas aeruginosa) and Gram positive (Enterococcus faecalis and Pediococcus acidilactici) bacteria at low concentration of silver present in the shell, with more efficacy against Gram negative bacteria. TEM and flow cytometric studies showed that the core-shell NPs attached to the bacterial surface and caused membrane damage leading to cell death. The enhanced antibacterial properties of Au@Ag core-shell NPs was possibly due to the more active silver atoms in the shell surrounding gold core due to high surface free energy of the surface Ag atoms owing to shell thinness in the bimetallic NP structure.Herein we report the development of bimetallic Au@Ag core-shell nanoparticles (NPs) where gold nanoparticles (Au NPs) served as the seeds for continuous deposition of silver atoms on its surface. The core-shell structure and morphology were examined by UV-Vis spectroscopy, transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis and X-ray diffraction (XRD). The core-shell NPs showed antibacterial activity against both Gram negative (Escherichia coli and Pseudomonas aeruginosa) and Gram positive (Enterococcus faecalis and Pediococcus acidilactici) bacteria at low concentration of silver present in the shell, with more efficacy against Gram negative bacteria. TEM and flow cytometric studies showed that the core-shell NPs attached to the bacterial surface and caused membrane damage leading to cell death. The enhanced antibacterial properties of Au@Ag core-shell NPs was

  1. SGLT1 activity in lung alveolar cells of diabetic rats modulates airway surface liquid glucose concentration and bacterial proliferation.

    PubMed

    Oliveira, Tales Lyra; Candeia-Medeiros, Návylla; Cavalcante-Araújo, Polliane M; Melo, Igor Santana; Fávaro-Pípi, Elaine; Fátima, Luciana Alves; Rocha, Antônio Augusto; Goulart, Luiz Ricardo; Machado, Ubiratan Fabres; Campos, Ruy R; Sabino-Silva, Robinson

    2016-01-01

    High glucose concentration in the airway surface liquid (ASL) is an important feature of diabetes that predisposes to respiratory infections. We investigated the role of alveolar epithelial SGLT1 activity on ASL glucose concentration and bacterial proliferation. Non-diabetic and diabetic rats were intranasally treated with saline, isoproterenol (to increase SGLT1 activity) or phlorizin (to decrease SGLT1 activity); 2 hours later, glucose concentration and bacterial proliferation (methicillin-resistant Sthaphylococcus aureus, MRSA and Pseudomonas aeruginosa, P. aeruginosa) were analyzed in bronchoalveolar lavage (BAL); and alveolar SGLT1 was analyzed by immunohistochemistry. BAL glucose concentration and bacterial proliferation increased in diabetic animals: isoproterenol stimulated SGLT1 migration to luminal membrane, and reduced (50%) the BAL glucose concentration; whereas phlorizin increased the BAL glucose concentration (100%). These regulations were accompanied by parallel changes of in vitro MRSA and P. aeruginosa proliferation in BAL (r = 0.9651 and r = 0.9613, respectively, Pearson correlation). The same regulations were observed in in vivo P. aeruginosa proliferation. In summary, the results indicate a relationship among SGLT1 activity, ASL glucose concentration and pulmonary bacterial proliferation. Besides, the study highlights that, in situations of pulmonary infection risk, such as in diabetic subjects, increased SGLT1 activity may prevent bacterial proliferation whereas decreased SGLT1 activity can exacerbate it. PMID:26902517

  2. SGLT1 activity in lung alveolar cells of diabetic rats modulates airway surface liquid glucose concentration and bacterial proliferation

    PubMed Central

    Oliveira, Tales Lyra; Candeia-Medeiros, Návylla; Cavalcante-Araújo, Polliane M.; Melo, Igor Santana; Fávaro-Pípi, Elaine; Fátima, Luciana Alves; Rocha, Antônio Augusto; Goulart, Luiz Ricardo; Machado, Ubiratan Fabres; Campos, Ruy R.; Sabino-Silva, Robinson

    2016-01-01

    High glucose concentration in the airway surface liquid (ASL) is an important feature of diabetes that predisposes to respiratory infections. We investigated the role of alveolar epithelial SGLT1 activity on ASL glucose concentration and bacterial proliferation. Non-diabetic and diabetic rats were intranasally treated with saline, isoproterenol (to increase SGLT1 activity) or phlorizin (to decrease SGLT1 activity); 2 hours later, glucose concentration and bacterial proliferation (methicillin-resistant Sthaphylococcus aureus, MRSA and Pseudomonas aeruginosa, P. aeruginosa) were analyzed in bronchoalveolar lavage (BAL); and alveolar SGLT1 was analyzed by immunohistochemistry. BAL glucose concentration and bacterial proliferation increased in diabetic animals: isoproterenol stimulated SGLT1 migration to luminal membrane, and reduced (50%) the BAL glucose concentration; whereas phlorizin increased the BAL glucose concentration (100%). These regulations were accompanied by parallel changes of in vitro MRSA and P. aeruginosa proliferation in BAL (r = 0.9651 and r = 0.9613, respectively, Pearson correlation). The same regulations were observed in in vivo P. aeruginosa proliferation. In summary, the results indicate a relationship among SGLT1 activity, ASL glucose concentration and pulmonary bacterial proliferation. Besides, the study highlights that, in situations of pulmonary infection risk, such as in diabetic subjects, increased SGLT1 activity may prevent bacterial proliferation whereas decreased SGLT1 activity can exacerbate it. PMID:26902517

  3. Effect of biomass concentration on methane oxidation activity using mature compost and graphite granules as substrata.

    PubMed

    Xie, S; O'Dwyer, T; Freguia, S; Pikaar, I; Clarke, W P

    2016-10-01

    Reported methane oxidation activity (MOA) varies widely for common landfill cover materials. Variation is expected due to differences in surface area, the composition of the substratum and culturing conditions. MOA per methanotrophic cell has been calculated in the study of natural systems such as lake sediments to examine the inherent conditions for methanotrophic activity. In this study, biomass normalised MOA (i.e., MOA per methanotophic cell) was measured on stabilised compost, a commonly used cover in landfills, and on graphite granules, an inert substratum widely used in microbial electrosynthesis studies. After initially enriching methanotrophs on both substrata, biomass normalised MOA was quantified under excess oxygen and limiting methane conditions in 160ml serum vials on both substrata and blends of the substrata. Biomass concentration was measured using the bicinchoninic acid assay for microbial protein. The biomass normalised MOA was consistent across all compost-to-graphite granules blends, but varied with time, reflecting the growth phase of the microorganisms. The biomass normalised MOA ranged from 0.069±0.006μmol CH4/mg dry biomass/h during active growth, to 0.024±0.001μmol CH4/mg dry biomass/h for established biofilms regardless of the substrata employed, indicating the substrata were equally effective in terms of inherent composition. The correlation of MOA with biomass is consistent with studies on methanotrophic activity in natural systems, but biomass normalised MOA varies by over 5 orders of magnitude between studies. This is partially due to different methods being used to quantify biomass, such as pmoA gene quantification and the culture dependent Most Probable Number method, but also indicates that long term exposure of materials to a supply of methane in an aerobic environment, as can occur in natural systems, leads to the enrichment and adaptation of types suitable for those conditions. PMID:27515185

  4. Effect of Phosphoric Acid Concentration on the Characteristics of Sugarcane Bagasse Activated Carbon

    NASA Astrophysics Data System (ADS)

    Adib, M. R. M.; Suraya, W. M. S. W.; Rafidah, H.; Amirza, A. R. M.; Attahirah, M. H. M. N.; Hani, M. S. N. Q.; Adnan, M. S.

    2016-07-01

    Impregnation method is one of the crucial steps involved in producing activated carbon using chemical activation process. Chemicals employed in this step is effective at decomposing the structure of material and forming micropores that helps in adsorption of contaminants. This paper explains thorough procedures that have been involved in producing sugarcane bagasse activated carbon (SBAC) by using 5%, 10%, 20%, 30% phosphoric acid (H3PO4) during the impregnation step. Concentration of H3PO4 used in the process of producing SBAC was optimized through several tests including bulk density, ash content, iodine adsorption and pore size diameter and the charactesristic of optimum SBAC produced has been compared with commercial activated carbon (CAC). Batch study has been carried out by using the SBAC produced from optimum condition to investigate the performance of SBAC in removal of turbidity and chemical oxygen demand (COD) from textile wastewater. From characteristic study, SBAC with 30% H3PO4 has shown the optimum value of bulk density, ash content, iodine adsorption and pore size diameter of 0.3023 g cm-3, 4.35%, 974.96 mg/g and 0.21-0.41 µm, respectively. These values are comparable to the characteristics of CAC. Experimental result from the batch study has been concluded that the SBAC has a promising potential in removing turbidity and COD of 75.5% and 66.3%, respectively which was a slightly lower than CAC which were able to remove 82.8% of turbidity and 70% of COD. As a conclusion, the SBAC is comparable with CAC in terms of their characteristics and the capability of removing contaminants from textile wastewater. Therefore, it has a commercial value to be used as an alternative of low-cost material in producing CAC.

  5. Soil-gas radon concentration monitoring in an active granite quarry from Central Portugal

    NASA Astrophysics Data System (ADS)

    Neves, Luís.; Barbosa, Susana; Pereira, Alcides; Aumento, Fabrizio

    2010-05-01

    This study was carried out in an active quarry located nearby the town of Nelas (Central Portugal), with the primary objective of assessing the effect of regular explosions on soil-gas radon concentrations. Here, a late-orogenic Hercynian porphyritic biotite granite occurs and is exploited for the production of high quality aggregates for different building purposes. This granite is part of the Beiras batholiths, being a geochemically moderately evolved rock, slightly peraluminous, and widely known by the frequent occurrence of associated uranium mineralizations. In fact, more than 4000t of U3O8 was produced from 60 mines of the Beiras region in the last century, over a wide area of more than 10.000 km2, and thousands of anomalies related with the local accumulation of uranium in fault filling materials, metasedimentary enclaves and doleritic veins were recognized during prospecting works. The heterogeneity of uranium distribution in this rock is reflected at the test site; indeed, a gamma ray survey shows that some of the faults that occur in the quarry are slightly mineralized. A total of 7 radon monitoring stations were implemented in the quarry, at a typical depth comprised between 1 and 2 meters, in holes drilled for the purpose. Aware RM-70 pancake GM detectors were used, sensitive to alpha, beta and gamma/X-rays above 10 keV, connected to palmtop computers for data registration (1 minute interval) and power supplied by batteries. Monitoring was carried out during 6 months, in Spring/Summer conditions and the exact time of each explosion was registered manually. Several problems of data loss and power supply affected the stations during the experiment, leading to discontinuities in the records. Still the available data showed important differences in the soil-gas radon concentrations between stations, which can be explained by the heterogeneity of uranium distribution in the rock and increased local permeability. Furthermore, all stations showed a clear daily

  6. Agrosecurity for concentrated animal feeding operations (CAFOs): commentary on recent planning activities.

    PubMed

    DeOtte, Robert E

    2007-06-01

    Agrosecurity has become a major concern for livestock operations. This paper reviews post 11 September 2001, American planning activities and offers commentary on issues related to these plans. A critical issue is the need for as many people as possible to be aware of plans and preparations already completed and actions still necessary. There is a sizeable disparity within the animal agriculture sector about information known and understood at different levels. Several readiness exercises have highlighted the need for better broad-spectrum communication: communication within disciplines, within agencies, across disciplines, across agencies, and most importantly everyone involved must talk with industry at all levels. The best preparation involves close coordination between law enforcement, industry, governmental agencies at all levels, academia, risk managers and communicators, veterinarians, engineers, economists, game theorists, and others. This paper features issues related to concentrated animal feeding operations (CAFOs), highlights some of the lessons learned through these exercises, and discusses a plan of action patterned after the activities of a regional agricultural jurisdictional working group. PMID:17692146

  7. IFCC primary reference procedures for the measurement of catalytic activity concentrations of enzymes at 37 degrees C. Part 1. The concept of reference procedures for the measurement of catalytic activity concentrations of enzymes.

    PubMed

    Siekmann, Lothar; Bonora, Roberto; Burtis, Carl A; Ceriotti, Ferruccio; Clerc-Renaud, Pascale; Férard, Georges; Ferrero, Carlo A; Forest, Jean-Claude; Franck, Paul F H; Gella, F Javier; Hoelzel, Wieland; Jørgensen, Poul Jørgen; Kanno, Takashi; Kessner, Art; Klauke, Rainer; Kristiansen, Nina; Lessinger, Jean-Marc; Linsinger, Thomas P J; Misaki, Hideo; Mueller, Mathias M; Panteghini, Mauro; Pauwels, Jean; Schiele, Françoise; Schimmel, Heinz G; Vialle, Arlette; Weidemann, Gerhard; Schumann, Gerhard

    2002-06-01

    This paper is the first in a series dealing with reference procedures for the measurement of catalytic activity concentrations of enzymes at 37 degrees C and with the certification of reference preparations. Other parts deal with: Part 2. Reference Procedure for the Measurement of Catalytic Concentration of Creatine Kinase; Part 3. Reference Procedure for the Measurement of Catalytic Concentration of Lactate Dehydrogenase; Part 4. Reference Procedure for the Measurement of Catalytic Concentration of Alanine Aminotransferase; Part 5. Reference Procedure for the Measurement of Catalytic Concentration of Aspartate Aminotransferase; Part 6. Reference Procedure for the Measurement of Catalytic fication of Four Reference Materials for the Determination of Enzymatic Activity of y-Glutamyltransferase, Lactate Dehydrogenase, Alanine Aminotransferase and Creatine Kinase at 37 degrees C. A document describing the determination of preliminary reference values is also in preparation. PMID:12211661

  8. Active and Passive Microwave Retrieval Algorithm for Hydrometeor Concentration Profiles: Application to the HAMP Instrument

    NASA Astrophysics Data System (ADS)

    Orlandi, E.; Mech, M.; Crewell, S.; Lammert, A.

    2012-12-01

    Clouds and precipitation play an important role in the atmospheric water cycle and radiation budget. Unfortunately, the understanding of the processes involved in cloud and precipitation formation and their description in global and regional models are still poor. To improve our understanding of these processes and to reduce model uncertainties, new observation and retrieval techniques are needed. The upcoming Global Precipitation Mission (GPM) provides a combination of a 36 GHz cloud radar and a suite of passive microwave instruments. In the retrieval development process for this and other upcoming missions, airborne platforms are a useful tool to test the algorithms exploiting the synergy of active and passive microwave instruments, and to validate satellite retrievals. In this respect HAMP (Microwave Package for HALO, the High Altitude Long Range aircraft), consisting of a 36 GHz Doppler cloud radar and a 26-channel radiometer, is an ideal test-bed. HAMP radiometers have frequencies along absorption lines (22, 60, 118 and 183 GHz) and in window regions, overlapping with those of AMSU A and B. HAMP will participate in early 2013 in the dedicated remote sensing HALO mission NARVAL (Next-generation Aircraft Remote-sensing for VALidation studies). During NARVAL, the HALO payload will include a water vapor lidar and drop sondes in addition to HAMP. The NARVAL campaign will thus be a excellent opportunity to test a newly developed retrieval algorithm, which exploits the synergy between passive and active microwave observations. In this work we present a Bayesian algorithm to retrieve precipitation rate, liquid and frozen hydrometeor concentration, as well as temperature and humidity profiles from the synergetic use of active and passive microwave nadir observations. Temperature and humidity are derived solely from passive radiometer measurements while the combined cloud radar and radiometer observations are used to retrieve hydrometeor concentration profiles. Lidar

  9. Effect of gut active carbohydrates on plasma IgG concentrations in piglets and calves.

    PubMed

    Lazarevic, M; Spring, P; Shabanovic, M; Tokic, V; Tucker, L A

    2010-06-01

    Improving immune status in neonates is crucial to health and production. Gut active carbohydrates (GAC) have been associated with increasing immunoglobin levels and immonucompetence development in mammals. The objective of the following studies was to evaluate whether GAC (mannan-oligosaccharides) applied orally to progeny immediately following parturition, improved blood plasma immunoglobulin (Ig) type G concentrations in piglets and calves. Three trials were conducted comparing control groups with those receiving GAC orally. The first two trials used piglets that were monitored for blood IgG at 2 days of age and for changes in body weight (BW), and the third trial monitored calf IgG from birth to 21 days of age. Piglets in the experimental group received 0.75 g GAC in 10 ml saline at birth and 24 h of age. The calf trial compared the control group against calves that received 22.5 g GAC mixed into 4.5 l of colostrum (to give 5 g/l) in the first 24 h after parturition. Blood serum samples were taken at 2 days post partum in piglets, and at several time points from 6 h to 21 days of age in calves, and were analysed for IgG levels by radial immunodiffusion. In the first piglet trial, significantly higher levels (32%) of IgG were observed for piglets fed GAC (P < 0.001), and in the second, IgG concentration was elevated by 23% (P < 0.01) and BW increased by 9% (P = 0.023) with GAC supplementation. Significant improvements for calves were recorded at all time points in those fed GAC (P < 0.05), with an increase in serum IgG observed after the first day, which was maintained throughout the sampling period, resulting in a difference of 39% at the end of the trial (21 d). These findings form a basis for further studies, which are required to investigate possible modes of action involved in enhancing blood immunoglobulin concentrations in young animals, and the longer-term effects this may have on the development of the immune response. PMID:22444266

  10. Selenium concentrations and enzyme activities of glutathione metabolism in wild long-tailed ducks and common eiders

    USGS Publications Warehouse

    Franson, J. Christian; Hoffman, David J.; Flint, Paul L.

    2011-01-01

    The relationships of selenium (Se) concentrations in whole blood with plasma activities of total glutathione peroxidase, Se-dependent glutathione peroxidase, and glutathione reductase were studied in long-tailed ducks (Clangula hyemalis) and common eiders (Somateria mollissima) sampled along the Beaufort Sea coast of Alaska, USA. Blood Se concentrations were >8 μg/g wet weight in both species. Linear regression revealed that the activities of total and Se-dependent glutathione peroxidase were significantly related to Se concentrations only in long-tailed ducks, raising the possibility that these birds were experiencing early oxidative stress.

  11. Evaluation of Activity Concentration Values and Doses due to the Transport of Low Level Radioactive Material

    SciTech Connect

    Rawl, Richard R; Scofield, Patricia A; Leggett, Richard Wayne; Eckerman, Keith F

    2010-04-01

    The International Atomic Energy Agency (IAEA) initiated an international Coordinated Research Project (CRP) to evaluate the safety of transport of naturally occurring radioactive material (NORM). This report presents the United States contribution to that IAEA research program. The focus of this report is on the analysis of the potential doses resulting from the transport of low level radioactive material. Specific areas of research included: (1) an examination of the technical approach used in the derivation of exempt activity concentration values and a comparison of the doses associated with the transport of materials included or not included in the provisions of Paragraph 107(e) of the IAEA Safety Standards, Regulations for the Safe Transport of Radioactive Material, Safety Requirements No. TS-R-1; (2) determination of the doses resulting from different treatment of progeny for exempt values versus the A{sub 1}/A{sub 2} values; and (3) evaluation of the dose justifications for the provisions applicable to exempt materials and low specific activity materials (LSA-I). It was found that the 'previous or intended use' (PIU) provision in Paragraph 107(e) is not risk informed since doses to the most highly exposed persons (e.g., truck drivers) are comparable regardless of intended use of the transported material. The PIU clause can also have important economic implications for co-mined ores and products that are not intended for the fuel cycle but that have uranium extracted as part of their industrial processing. In examination of the footnotes in Table 2 of TS-R-1, which identifies the progeny included in the exempt or A1/A2 values, there is no explanation of how the progeny were selected. It is recommended that the progeny for both the exemption and A{sub 1}/A{sub 2} values should be similar regardless of application, and that the same physical information should be used in deriving the limits. Based on the evaluation of doses due to the transport of low-level NORM

  12. Platelet Activation Test in Unprocessed Blood (Pac-t-UB) to Monitor Platelet Concentrates and Whole Blood of Thrombocytopenic Patients

    PubMed Central

    Roest, Mark; van Holten, Thijs C.; Fleurke, Ger-Jan; Remijn, Jasper A.

    2013-01-01

    Summary Background Platelet concentrate transfusion is the standard treatment for hemato-oncology patients to compensate for thrombocytopenia. We have developed a novel platelet activation test in anticoagulated unprocessed blood (pac-t-UB) to determine platelet function in platelet concentrates and in blood of thrombocytopenic patients. Methods We have measured platelet activity in a platelet concentrate and in anticoagulated unprocessed blood of a post-transfusion thrombocytopenic patient. Results Our data show time-dependent platelet activation by GPVI agonist (collagen related peptide; CRP), PAR-1 agonist (SFLLRN), P2Y12 agonist (ADP), and thromboxane receptor agonist (U46619) in a platelet concentrate. Furthermore, pac-t-UB showed time-dependent platelet activation in unprocessed blood of a post-transfusion patient with thrombocytopenia. Testing platelet function by different agonists in relation to storage show that 3-day-old platelet concentrates are still reactive to the studied agonists. This reactivity rapidly drops for each agonists during longer storage. Discussion Pac-t-UB is a novel tool to estimate platelet function by different agonists in platelet concentrates and in unprocessed blood of thrombocytopenic patients. In the near future, we will validate whether pac-t-UB is an adequate test to monitor the quality of platelet concentrates and whether pac-t-UB predicts the bleeding risk of transfused thrombocytopenic patients. PMID:23652405

  13. 76 FR 48882 - Agency Information Collections Activities; Comment Request for Uranium Concentrations in Private...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-09

    ... Concentrations in Private Wells in South-East New Hampshire AGENCY: United States Geological Survey (USGS... Collection 1028-NEW, Uranium concentrations in private wells in south-east New Hampshire, in the subject line... concentrations in groundwater that is used for private domestic drinking water are not well characterized...

  14. In vitro bioassays for anticancer drug screening: effects of cell concentration and other assay parameters on growth inhibitory activity.

    PubMed

    Lieberman, M M; Patterson, G M; Moore, R E

    2001-11-01

    In vitro growth inhibition assays were performed using human cancer cell lines at various concentrations with experimental anticancer drugs such as the cryptophycins and other cytotoxins. The effect of variations in assay parameters on the observed growth inhibition of these anticancer therapeutic agents was determined. The results demonstrated that the observed inhibitory activity of these compounds varied inversely with the cell concentrations used. The observed differences in activity between different cytotoxins were not necessarily proportionate. Thus, the relative activities of two toxins also varied with cell concentration. Furthermore, the sensitivity of these cell lines to the cytostatic purine analog, 6-mercaptopurine (used as a control), varied with cell concentration as well. The activity of this compound was dependent on the medium used for cell growth, yielding good activity in Eagle's minimum essential medium, but not in Ham's F-12 (Kaigin) medium. Moreover, growth inhibition by cryptophycin as well as 6-mercaptopurine was also dependent on the serum concentration in the medium. Finally, the sensitivity of the cancer cell lines to various organic solvents commonly used as drug vehicles for in vitro testing, such as ethanol, dimethylformamide, and dimethylsulfoxide, was likewise found to vary inversely with cell concentration. PMID:11578805

  15. The Comparative Analysis of Antioxidant and Biological Activity for the Dendropanax morbifera LEV. Leaves Extracted by Different Ethanol Concentrations.

    PubMed

    Nakamura, Masaya; Ra, Jong-Hwan; Kim, Ju-Sung

    2016-01-01

    The different concentrations of ethanol (20-100%) and distilled water extract for Dendropanax morbifera LEV. leaves were evaluated to induce antioxidant and biological activity employed by variety of assays. The 20%, 80%, and 100% ethanol extract demonstrated the relatively higher activity, whereas distilled water, 40%, and 60% ethanol extracts exhibited the lower antioxidant and biological activity. Especially, 80% ethanol extract showed the remarkably higher radical scavenging activity, reducing power, total phenol and flavonoid content, α-glucosidase, and tyrosinase inhibitory activity, and alcohol dehydrogenases (ADH) and aldehyde dehydrogenase (ALDH) activity. Also, 100% ethanol extract exhibited relatively greater activity, but there did not show significant radical scavenging activity. Furthermore, there were 50% and 30% promotion effect for ADH activity assay and 80% and 40% promotion effect for ALDH activity assay in 80% and 100% ethanol extract, respectively. In addition, in the minimum inhibitory concentration (MIC), all extracts except for distilled water extract inhibited Bacillus cereus, Staphylococcus aureus subsp. aureus, Escherichia coli. For Pichia jadinii, whole extracts effectively inhibited yeast multiplication at concentration of 125 μg/mL for 100% ethanol extract and 250 μg/mL for the rest of extract. These result indicated that D. morbifera LEV. leaves extracted by 80% ethanol would be the ideal extracting solution to maximize inherent antioxidant and biological activity agent. PMID:27592831

  16. Activation of ENaC by AVP contributes to the urinary concentrating mechanism and dilution of plasma.

    PubMed

    Mironova, Elena; Chen, Yu; Pao, Alan C; Roos, Karl P; Kohan, Donald E; Bugaj, Vladislav; Stockand, James D

    2015-02-01

    Arginine vasopressin (AVP) activates the epithelial Na(+) channel (ENaC). The physiological significance of this activation is unknown. The present study tested if activation of ENaC contributes to AVP-sensitive urinary concentration. Consumption of a 3% NaCl solution induced hypernatremia and plasma hypertonicity in mice. Plasma AVP concentration and urine osmolality increased in hypernatremic mice in an attempt to compensate for increases in plasma tonicity. ENaC activity was elevated in mice that consumed 3% NaCl solution compared with mice that consumed a diet enriched in Na(+) with ad libitum tap water; the latter diet does not cause hypernatremia. To determine whether the increase in ENaC activity in mice that consumed 3% NaCl solution served to compensate for hypernatremia, mice were treated with the ENaC inhibitor benzamil. Coadministration of benzamil with 3% NaCl solution decreased urinary osmolality and increased urine flow so that urinary Na(+) excretion increased with no effect on urinary Na(+) concentration. This decrease in urinary concentration further increased plasma Na(+) concentration, osmolality, and AVP concentration in these already hypernatremic mice. Benzamil similarly compromised urinary concentration in water-deprived mice and in mice treated with desmopressin. These results demonstrate that stimulation of ENaC by AVP plays a critical role in water homeostasis by facilitating urinary concentration, which can compensate for hypernatremia or exacerbate hyponatremia. The present findings are consistent with ENaC in addition to serving as a final effector of the renin-angiotensin-aldosterone system and blood pressure homeostasis, also playing a key role in water homeostasis by regulating urine concentration and dilution of plasma. PMID:25391898

  17. Geobacter sp. SD-1 with enhanced electrochemical activity in high-salt concentration solutions.

    PubMed

    Sun, Dan; Call, Douglas; Wang, Aijie; Cheng, Shaoan; Logan, Bruce E

    2014-12-01

    An isolate, designated strain SD-1, was obtained from a biofilm dominated by Geobacter sulfurreducens in a microbial fuel cell. The electrochemical activity of strain SD-1 was compared with type strains, G. sulfurreducens PCA and Geobacter metallireducens GS-15, and a mixed culture in microbial electrolysis cells. SD-1 produced a maximum current density of 290 ± 29 A m−3 in a high-concentration phosphate buffer solution (PBS-H, 200 mM). This current density was significantly higher than that produced by the mixed culture (189 ± 44 A m−3) or the type strains (< 70 A m−3). In a highly saline water (SW; 50 mM PBS and 650 mM NaCl), current by SD-1 (158 ± 4 A m−3) was reduced by 28% compared with 50 mM PBS (220 ± 4 A m−3), but it was still higher than that of the mixed culture (147 ± 19 A m−3), and strains PCA and GS-15 did not produce any current. Electrochemical tests showed that the improved performance of SD-1 was due to its lower charge transfer resistance and more negative potentials produced at higher current densities. These results show that the electrochemical activity of SD-1 was significantly different than other Geobacter strains and mixed cultures in terms of its salt tolerance. PMID:25756125

  18. Increased concentration of plasminogen activator inhibitor-1 and fibrinogen in individuals with metabolic syndrome.

    PubMed

    Palomo, Iván G; Gutiérrez, César L; Alarcón, Marcelo L; Jaramillo, Julio C; Segovia, Fabián M; Leiva, Elba M; Mujica, Verónica E; Icaza, Gloria N; Díaz, Nora S; Moore-Carrasco, Rodrigo

    2009-01-01

    Metabolic syndrome (MS) is closely linked to a generalized metabolic disorder referred to as insulin resistance. Disturbances in the hemostasis and fibrinolytic systems are a feature of MS. The aim of this study was to determine the concentration levels of fibrinogen and plasminogen activator inhibitor-1 (PAI-1) in a group of patients with MS with respect to a non-MS group, and to evaluate their possible relation with other risk factors in MS. The study was carried out in a total of 186 male and female non-smoking individuals aged 45-64 years, 93 with MS (ATP III criteria) and 93 without MS. Plasmatic levels of PAI-1 were measured by ELISA, and those of fibrinogen by the Claus method. The plasmatic levels of PAI-1 (men 49.2±19.8 vs. 35.0±12.2 ng/ml and women 42.0±19.7 vs. 31.6±14.6 ng/ml; p=0.0026) and fibrinogen (274.0±82.1 vs. 232.7±66.6 ng/ml; p=0.0002) were significantly higher in the MS group than in the non-MS group. PAI-1 was significantly associated with diastolic blood pressure, triglycerides and waist circumference. Fibrinogen was negatively associated with HDL-c. High plasmatic levels of PAI-1 and fibrinogen contribute to the cardiovascular risk that characterizes individuals with MS. PMID:21475821

  19. A comparison of barley malt osmolyte concentrations and standard malt quality measurements as indicators of barley malt amylolytic enzyme activities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was conducted to test the hypothesis that barley malt osmolyte concentrations (OC) would correlate better with malt a-amylase, ß-amylase, and limit dextrinase activities than do the standard malt quality measurements (malt extract [ME], diastatic power [DP], ASBC a-amylase activity, solub...

  20. Sulforhodamine 101, a widely used astrocyte marker, can induce cortical seizure-like activity at concentrations commonly used.

    PubMed

    Rasmussen, Rune; Nedergaard, Maiken; Petersen, Nicolas Caesar

    2016-01-01

    Sulforhodamine 101 (SR101) is a preferential astrocyte marker widely used in 2-photon microscopy experiments. Here we show, that topical loading of two commonly used SR101 concentrations, 100 μM and 250 μM when incubated for 10 min, can induce seizure-like local field potential (LFP) activity in both anaesthetized and awake mouse sensori-motor cortex. This cortical seizure-like activity develops in less than ten minutes following topical loading, and when applied longer, these neuronal discharges reliably evoke contra-lateral hindlimb muscle contractions. Short duration (<1 min) incubation of 100 μM and 250 μM SR101 or application of lower concentrations 25 μM and 50 μM of SR101, incubated for 30 and 20 min, respectively, did not induce abnormal LFP activity in sensori-motor cortex, but did label astrocytes, and may thus be considered more appropriate concentrations for in vivo astrocyte labeling. In addition to label astrocytes SR101 may, at 100 μM and 250 μM, induce abnormal neuronal activity and interfere with cortical circuit activity. SR101 concentration of 50 μM or lower did not induce abnormal neuronal activity. We advocate that, to label astrocytes with SR101, concentrations no higher than 50 μM should be used for in vivo experiments. PMID:27457281

  1. Sulforhodamine 101, a widely used astrocyte marker, can induce cortical seizure-like activity at concentrations commonly used

    PubMed Central

    Rasmussen, Rune; Nedergaard, Maiken; Petersen, Nicolas Caesar

    2016-01-01

    Sulforhodamine 101 (SR101) is a preferential astrocyte marker widely used in 2-photon microscopy experiments. Here we show, that topical loading of two commonly used SR101 concentrations, 100 μM and 250 μM when incubated for 10 min, can induce seizure-like local field potential (LFP) activity in both anaesthetized and awake mouse sensori-motor cortex. This cortical seizure-like activity develops in less than ten minutes following topical loading, and when applied longer, these neuronal discharges reliably evoke contra-lateral hindlimb muscle contractions. Short duration (<1 min) incubation of 100 μM and 250 μM SR101 or application of lower concentrations 25 μM and 50 μM of SR101, incubated for 30 and 20 min, respectively, did not induce abnormal LFP activity in sensori-motor cortex, but did label astrocytes, and may thus be considered more appropriate concentrations for in vivo astrocyte labeling. In addition to label astrocytes SR101 may, at 100 μM and 250 μM, induce abnormal neuronal activity and interfere with cortical circuit activity. SR101 concentration of 50 μM or lower did not induce abnormal neuronal activity. We advocate that, to label astrocytes with SR101, concentrations no higher than 50 μM should be used for in vivo experiments. PMID:27457281

  2. Anaemia, Serum Iron Concentrations and δ-Aminolevulinate Dehydratase Activity in Laying Hens Infected Naturally by Salmonella Gallinarum.

    PubMed

    Machado, A C; Boiago, M M; do Carmo, G M; Bottari, N B; Araujo, D N; Giuriatti, J; Morsch, V M; Schetinger, M R C; Casagrande, R A; Wisser, C S; Stefani, L M; Alves, M S; Da Silva, A S

    2016-07-01

    The aim of this study was to evaluate anaemia, serum iron concentrations and δ-aminolevulinate dehydratase (ALA-D) activity in laying hens infected naturally by Salmonella Gallinarum and having severe hepatic lesions. Liver and serum samples were collected from 27 laying hens (20 infected and seven uninfected). The δ-ALA-D activity, haematocrit and serum iron concentrations were evaluated. There were significant decreases in δ-ALA-D activity, haematocrit and serum iron concentrations (P <0.01) in birds infected by S. Gallinarum when compared with uninfected birds. There was a positive correlation (P <0.001) between serum iron concentration, haematocrit (r(2) = 0.82) and δ-ALA-D activity (r(2) = 0.75). A positive correlation was also observed between δ-ALA-D activity and haematocrit (r(2) = 0.78; P <0.01). Liver samples showed moderate focal coagulative necrosis associated with infiltration of lymphoplasmacytic cells, macrophages and heterophils. The anaemia in the infected hens may be related to reduction in δ-ALA-D activity and serum iron concentrations, since both are important for haemopoiesis. PMID:27262503

  3. Effect of various concentration of sulfuric acid for Nafion membrane activation on the performance of fuel cell

    NASA Astrophysics Data System (ADS)

    Pujiastuti, Sri; Onggo, Holia

    2016-02-01

    This work proposes an activation treatment to Nafion 117 membrane with sulfuric acid in various concentrations. The main goal of this study is to increase the Nafion 117 membrane performance, which is determined by proton number in the membrane and membrane performance in Polymer Electrolyte Membrane Fuel Cell (PEMFC). This work was developed using sulfuric acids in four different concentrations: 1, 2, 3, and 4 M. The surface morphology and functional groups of activated membranes were studied using Scanning Electron Microscope and Fourier Transform Infrared, respectively. The proton number absorbed in membranes was observed by gravimetric measurements. The performances of activated membranes in PEMFC were studied by single cell measurements with H2/O2 operation. The experimental results showed that activation of Nafion membrane did not change its surface morphology and functional groups. The proton number increased when the concentration of sulfuric acid is increased from 1 to 3 M and from 1 to 4 M. On the other hand, there is no significant increase when the concentration of sulfuric acid was increased from 1 to 2 M. Similar trends were observed when testing activated membrane performance in PEMFC, especially for current density at 0.6 V and maximum power. It is assumed that there is a correlation between the increase of sulfuric acid concentration in activation process with the increase of proton number in the membrane that are available for facilitating of transfer protons from the anode to the cathode.

  4. Responses of methanotrophic activity, community and EPS production to CH4 and O2 concentrations in waste biocover soils.

    PubMed

    Wei, Xiao-Meng; Su, Yao; Zhang, Hong-Tao; Chen, Min; He, Ruo

    2015-08-01

    Biocover soils are known to be a good alternative material to mitigate CH4 emissions from landfills to the atmosphere. In this study, 16 treatments with four O2 concentrations (∼0%, 5%, 10% and 21%) and four CH4 concentrations (i.e. 1%, 10%, 20% and 50%) were conducted to estimate extracellular polymeric substances (EPS) production, methanotrophic activity and community in response to CH4 and O2 concentrations in waste biocover soil (WBS). When the CH4 concentration was saturated for CH4 oxidation in the WBS, the continuous exposure of CH4 above the saturated concentrations could not obviously enhance CH4 oxidation activity. In the WBS, extracellular protein (ECP) production was negatively related with the tested CH4 concentrations, while both ECP and extracellular polysaccharides (ECPS) productions were positively related with the tested O2 concentrations. Cloning and terminal restriction fragment length polymorphism analyses showed that type I methanotrophs (Methylocaldum, Methylococcaceae, Methylomicrobium and Methylobacter) and type II methanotrophs (Methylosinus) dominated in the WBS. Among them, Methylocaldum and/or Methylococcaceae were sensitive to low O2 concentrations of ∼0%. Methylobacter had propensity to grow at low O2 concentrations of ∼0% and 5%, while Methylosinus preferred environments with high concentrations of CH4 (⩾10%) and O2 (21%). In the tested five environmental variables of ECPS, O2, EPS, CH4 and ECP, only ECPS and O2 concentrations had significant effect on the methanotrophic communities. These results suggested that O2 concentration in landfill covers should be paid more attention to optimize and sustain CH4 oxidation for mitigating CH4 emission from landfills. PMID:25921582

  5. First measurements on how pressure affects the half-life of 22Na: Comparison to theory and analog to 40K

    NASA Astrophysics Data System (ADS)

    Lee, K. K.; Nelson, R. O.; Rundberg, R.; Steinle-Neumann, G.

    2007-12-01

    Radioactive decay plays a central role in planetary sciences as appropriate decay schemes are used to date geological and astronomical processes and radioactivity provides an important source of heat in planetary bodies, both in their early history during accretion and differentiation and also over geological times. The most important isotopes that currently heat the Earth are 40K, 232Th, 235U and 238U. As radioactive decay is a nuclear process it is considered to be insensitive to external factors such as pressure or chemical environment. This has been shown to be true for α, β+ and β- processes, however, electron capture decay is dependent on the electron charge density at the nucleus of a compound, which is sensitive to the external environment. Using high-resolution Ge gamma-ray detectors to make relative measurements with 137Cs and the positron decay of 22Na, we measure how pressure affects the half-life of 22Na due to electron-capture decay. Our systematics look favorable for observing this small effect. We will compare our preliminary measurements with complementary ab-initio all-electron computations using the linearized augmented plane wave method (LAPW). Using 22Na as an analog for 40K, our results suggest that the pressure effect for 40K, combined with the opposing effects of high temperatures, will have little, discernible effect on the heat production in the deep Earth as our predicted changes are smaller than the uncertainties in the total decay constant for 40K. This work was supported in part by the Carnegie/DOE Alliance Center (CDAC), through the Stewardship Science Academic Alliances Program of the U.S. Department of Energy. The LANSCE facility is operated, and portions of this work were performed, by Los Alamos National Security, LLC, funded by the U.S. Department of Energy under Contract No. DE-AC52- 06NA25396.

  6. Age and Duration of Weathering by 40K-40Ar and 40Ar/39Ar Analysis of Potassium-Manganese Oxides.

    PubMed

    Vasconcelos, P M; Becker, T A; Renne, P R; Brimhall, G H

    1992-10-16

    Supergene cryptomelane [K(1-2)(Mn(3+)Mn(4+))(8)O(16). chiH(2)O] samples from deeply weathered pegmatites in southeastern Brazil subjected to (40)K-(40)Ar and (40)Ar/(39)Ar analysis yielded (40)K-(40)Ar dates ranging from 10.1 +/- 0.5 to 5.6 +/- 0.2 Ma (million years ago). Laser-probe (40)Ar/(39)Ar step-heating of the two most disparate samples yielded plateau dates of 9.94 +/- 0.05 and 5.59 +/- 0.10 Ma, corresponding, within 2 sigma, to the (40)K-(40)Ar dates. The results imply that deep weathering profiles along the eastern Brazilian margin do not reflect present climatic conditions but are the result of a long-term process that was already advanced by the late Miocene. Weathering ages predate pulses of continental sedimentation along the eastern Brazilian margin and suggest that there was a time lag between weathering and erosion processes and sedimentation processes. PMID:17833140

  7. In vitro activity of subinhibitory concentrations of quinolones on urea-splitting bacteria: effect on urease activity and on cell surface hydrophobicity.

    PubMed

    Ramadan, M A; Tawfik, A F; el-Kersh, T A; Shibl, A M

    1995-02-01

    The effect of subinhibitory concentrations of ciprofloxacin, lomefloxacin, norfloxacin, ofloxacin, and sparfloxacin on urease activity and on cell surface hydrophobicity of urea-splitting bacteria was examined. Quinolones at 0.5 MICs demonstrated variable effects on bacterial-urease activity. Norfloxacin inhibited enzyme activity in Proteus vulgaris and Proteus mirabilis, while other quinolones had no effects. In Morganella morganii, sparfloxacin and ciprofloxacin enhanced urease activity, particularly at the initial phase of growth. All quinolones tested showed no marked effect on urease activity by Providencia rettgeri. Quinolones at the same concentrations induced an increase in the cell surface hydrophobicity, which was strain-dependent. There was no correlation between urease inhibition and cell surface hydrophobicity. Inhibition of urease activity by quinolones, in addition to their antibacterial activities, may prevent the progression of urinary tissue damage and stone formation. PMID:7844396

  8. Time Evolution of Activity Concentration of Natural Emitters in a Scenario Affected By Previous Phosphogypsum Contamination

    NASA Astrophysics Data System (ADS)

    Villa, M.; Mantero, J.; Mosqueda, F.; Hurtado, S.; Manjón, G.; Vaca, F.; García-Tenorio, R.

    2008-08-01

    The estuary formed by the confluence of Tinto and Odiel river-mouths is located in the South of Spain, close to Huelva town. This estuary has been deeply studied through the years because it has a double particularity. On one hand, since the beginning of the 1960s, the estuary has been affected by direct and indirect phosphogypsum (pg.) releases from two phosphoric acid and fertilizers factories that are working in the area. On the other hand, the pyrite mining operations upstream the Odiel and Tinto rivers has caused historically the formation of H2SO4, through oxidation of the natural sulphur deposits, the acidification of the waters and the consequent mobilisation of heavy metals from the mining area to the Huelva estuary. As a consequence, enhancement contamination levels in natural emitters from the 238U series were found in the surroundings of the factories in the previous years to 1998. However, in 1998 the management policy of waste releases drastically changed in the area, and direct discharges to Tinto and Odiel River had to be ceased. A thorough study of the affected zone is being carried out. Riverbed sediments and water samples have been analyzed from four different sampling campaigns in the estuary during the years 1999, 2001, 2002 and 2005. Different radioanalytical techniques have been employed to obtain the activity concentrations of U-isotopes, Th-isotopes, 226Ra, 210Pb and 210Po. Furthermore, the results for the rates of de-contamination of the area are presented. This data will be discussed in order to establish the present status of the contamination in the area, and moreover, to predict the time-evolution of the self-cleaning

  9. Time Evolution of Activity Concentration of Natural Emitters in a Scenario Affected By Previous Phosphogypsum Contamination

    SciTech Connect

    Villa, M.; Hurtado, S.; Mantero, J.; Manjon, G.; Garcia-Tenorio, R.; Mosqueda, F.; Vaca, F.

    2008-08-07

    The estuary formed by the confluence of Tinto and Odiel river-mouths is located in the South of Spain, close to Huelva town. This estuary has been deeply studied through the years because it has a double particularity. On one hand, since the beginning of the 1960s, the estuary has been affected by direct and indirect phosphogypsum (pg.) releases from two phosphoric acid and fertilizers factories that are working in the area. On the other hand, the pyrite mining operations upstream the Odiel and Tinto rivers has caused historically the formation of H{sub 2}SO{sub 4}, through oxidation of the natural sulphur deposits, the acidification of the waters and the consequent mobilisation of heavy metals from the mining area to the Huelva estuary. As a consequence, enhancement contamination levels in natural emitters from the {sup 238}U series were found in the surroundings of the factories in the previous years to 1998. However, in 1998 the management policy of waste releases drastically changed in the area, and direct discharges to Tinto and Odiel River had to be ceased.A thorough study of the affected zone is being carried out. Riverbed sediments and water samples have been analyzed from four different sampling campaigns in the estuary during the years 1999, 2001, 2002 and 2005. Different radioanalytical techniques have been employed to obtain the activity concentrations of U-isotopes, Th-isotopes, {sup 226}Ra, {sup 210}Pb and {sup 210}Po. Furthermore, the results for the rates of de-contamination of the area are presented. This data will be discussed in order to establish the present status of the contamination in the area, and moreover, to predict the time-evolution of the self-cleaning.

  10. Fusion of satellite active and passive microwave data for sea ice type concentration estimates

    SciTech Connect

    Beaven, S.G.; Gogineni, S.; Carsey, F.D.

    1996-09-01

    Young first-year sea ice is nearly as important as open water in modulating heat flux between the ocean and atmosphere in the Arctic. Just after the onset of freeze-up, first-year ice is in the early stages of growth and will consist of young first-year and thin ice. The distribution of sea ice in this thickness range impacts heat transfer in the Arctic. Therefore, improving the estimates of ice concentrations in this thickness range is significant. NASA Team Algorithm (NTA) for passive microwave data inaccurately classifies sea ice during the melt and freeze-up seasons because it misclassifies multiyear ice as first-year ice. The authors developed a hybrid fusion technique for incorporating multiyear ice information derived form synthetic aperture radar (SAR) images into a passive microwave algorithm to improve ice type concentration estimates. First, they classified SAR images using a dynamic thresholding technique and estimated the multiyear ice concentration. Then they used the SAR-derived multiyear ice concentration constrain the NTA and obtained an improved first-year ice concentration estimate. They computed multiyear and first-year ice concentration estimates over a region in the eastern-central Arctic in which field observations of ice and in situ radar backscatter measurements were performed. With the NTA alone, the first-year ice concentration in the study area varied between 0.11 and 0.40, while the multiyear ice concentration varied form 0.63 to 0.39. With the hybrid fusion technique, the first-year ice concentration varied between 0.08 and 0.23 and the multiyear ice concentration was between 0.62 and 0.66. The fused estimates of first-year and multiyear ice concentration appear to be more accurate than NTA, based on ice observations that were logged aboard the US Coast Guard icebreaker Polar Star in the study area during 1991.

  11. A novel method for concentration evaluation of reading behaviors with electrical activity recorded on the scalp.

    PubMed

    Lin, Chern-Sheng; Lai, Yu-Chen; Lin, Jung-Chih; Wu, Pin-Yi; Chang, Hsing-Cheng

    2014-04-01

    In this paper, a concentration evaluation of reading behaviors with electrical signal detection on the head is presented. The electrode signal is extracted by brain-computer-interface (BCI) to monitor the user's degree of concentration, where the user is reminded by sound to concentrate, or teaching staffs are reminded to help users improve reading habits, in order to facilitate the user's ability to concentrate. The digital signal processing methods, such as the Kalman Filter, Fast Fourier Transform, the Hamming window, the average value of the total energy of a frame, correlation coefficient, and novel judgment algorithm are used to obtain the corresponding parameters of concentration evaluation. Users can correct their manner of reading with reminders. The repeated test results may be expected to lie with a probability of 95%. Such model training results in better learning effect. PMID:24631218

  12. Effect of periplasmic expression of recombinant mouse interleukin-4 on hydrogen peroxide concentration and catalase activity in Escherichia coli.

    PubMed

    Mehdizadeh Aghdam, Elnaz; Mahmoudi Azar, Lena; Barzegari, Abolfazl; Karimi, Farrokh; Mesbahfar, Majid; Samadi, Naser; Hejazi, Mohammad Saeid

    2012-12-15

    Oxidative stress occurs as a result of imbalance between generation and detoxification of reactive oxygen species (ROS). This kind of stress was rarely discussed in connection with foreign protein production in Escherichia coli. Relation between cytoplasmic recombinant protein expression with H(2)O(2) concentration and catalase activity variation was already reported. The periplasmic space of E. coli has different oxidative environment in relative to cytoplasm and there are some benefits in periplasmic expression of recombinant proteins. In this study, hydrogen peroxide concentration and catalase activity following periplasmic expression of mouse IL-4 were measured in E. coli. After construction of pET2mIL4 plasmid, the expression of recombinant mouse interleukin-4 (mIL-4) was confirmed. Then, the H(2)O(2) concentration and catalase activity variation in the cells were studied in exponential and stationary phases at various ODs and were compared to those of wild type cells and empty vector transformed cells. It was revealed that empty vector introduction and periplasmic recombinant protein expression increased significantly the H(2)O(2) concentration of the cells. However, the H(2)O(2) concentration in mIL-4 expressing cells was significantly higher than its concentration in empty vector transformed cells, demonstrating more effects of recombinant mIL-4 expression on H(2)O(2) elevation. Likewise, although catalase activity was reduced in foreign DNA introduced cells, it was more lowered following expression of recombinant proteins. Correlation between H(2)O(2) concentration elevation and catalase activity reduction with cell growth depletion is also demonstrated. It was also found that recombinant protein expression results in cell size increase. PMID:23000065

  13. Artificial activation of bovine and equine oocytes with cycloheximide, roscovitine, strontium, or 6-dimethylaminopurine in low or high calcium concentrations.

    PubMed

    Fernandes, Claudia Barbosa; Devito, Liani Gasparini; Martins, Lilian Rigatto; Blanco, Ieda Dala Pria; de Lima Neto, João Ferreria; Tsuribe, Patricia Myakawa; Gonçalves, Camila Gabriela Pereria; da Cruz Landim-Alvarenga, Fernanda

    2014-08-01

    Knowledge on parthenogenetic activation of oocytes is important to improve the efficiency of nuclear transfer (NT) and intracytoplasmic sperm injection (ICSI) because artificial activation of oocyte (AOA) is an essential step to achieve embryo production. Although different procedures for AOA have been established, the efficiency of in vitro production of embryos remains low, especially in equines and Bos taurus bovines. In an attempt to improve the techniques of NT and ICSI in bovine and equine species, we tested different combinations of drugs that had different mechanisms of action for the parthenogenetic activation of oocytes in these animals. The oocytes were collected, in vitro matured for 24 to 30 h and activated artificially, in the presence of low or high concentrations of calcium, with combinations of calcium ionophore (ionomycin) with cycloheximide, roscovitine, strontium, or 6-dimethylaminopurine (6-DMAP). For assessment of activation rates, oocytes were stained with Hoechst 33342 and observed under an inverted microscope. We showed that all combinations of drugs were equally efficient in activating bovine oocytes, with the best results obtained when high concentrations of calcium were adopted. For equine oocytes, high concentrations of calcium were not beneficial for the parthenogenetic activation and the combination of ionomycin with either 6-DMAP or roscovitine was effective in inducing artificial activation of oocytes. We believe that our preliminary findings provide some clues for the development of a better AOA protocol to be used with these species. PMID:23340077

  14. Pancreas-specific lipase concentrations and amylase and lipase activities in the peritoneal fluid of dogs with suspected pancreatitis.

    PubMed

    Chartier, Marie A; Hill, Steve L; Sunico, Sarena; Suchodolski, Jan S; Robertson, Jane E; Steiner, Joerg M

    2014-09-01

    Diagnosing acute pancreatitis in the dog can be challenging. The aim of this study was to determine the concentrations of pancreas-specific lipase immunoreactivity (cPLI), and the activities of amylase and lipase, in the peritoneal fluid from a population of dogs diagnosed with acute pancreatitis based on clinical signs, ultrasonographic findings and serum cPLI concentrations. In a prospective study, cPLI concentrations, and amylase and lipase activities, were measured in the peritoneal fluid of 14 dogs with pancreatitis and 19 dogs with non-pancreatic disease. The sensitivity and specificity of peritoneal fluid cPLI concentration (cut-off value 500 µg/L) were 100.0% (95% confidence interval, CI, 80.7-100.0%) and 94.7% (95% CI 76.7-99.7%), respectively. The sensitivity and specificity of peritoneal fluid amylase (cut-off value 1050 U/L) and lipase activities (cut-off value 500 U/L) were 71.4% (95% CI 44.5-90.2%) and 84.2% (95% CI 62.8-95.8%) for amylase activity, and 92.9% (95% CI 69.5-99.6%) and 94.7% (95% CI 76.7-99.7%) for lipase activity, respectively. In conclusion, peritoneal fluid cPLI concentration was highly sensitive as a complementary diagnostic tool in a group of dogs with suspected acute pancreatitis. Peritoneal fluid lipase activity was not as sensitive as cPLI concentration, but may also support a diagnosis of acute pancreatitis in dogs. PMID:25106805

  15. 40Ar/ 39Ar ages of CAMP in North America: Implications for the Triassic-Jurassic boundary and the 40K decay constant bias

    NASA Astrophysics Data System (ADS)

    Jourdan, F.; Marzoli, A.; Bertrand, H.; Cirilli, S.; Tanner, L. H.; Kontak, D. J.; McHone, G.; Renne, P. R.; Bellieni, G.

    2009-06-01

    a minor CAMP late tailing activity (190-194 Ma) which has been observed already for dykes and sills in Africa and Brazil. We speculate that, if genuine, this late activity can be due to a major extensional event, possibly heralding the oceanization process at ~ 190 Ma. Comparison between high quality U/Pb and 40Ar/ 39Ar ages of pegmatite lenses from the North Mountain basalts confirms a ~ 1% bias between the two chronometers. This discrepancy is likely attributed to the miscalibration of the 40K decay constants, in particular the electron capture branch.

  16. Investigation of the effects of summer melt on the calculation of sea ice concentration using active and passive microwave data

    NASA Technical Reports Server (NTRS)

    Cavalieri, Donald J.; Burns, Barbara A.; Onstott, Robert G.

    1990-01-01

    The effects of ice surface melt on microwave signatures and errors in the calculation of sea ice concentration are examined, using active and passive microwave data sets from the Marginal Ice Zone Experiment aircraft flights in the Fram Strait region. Consideration is given to the possibility of using SAR to supplement passive microwave data to unambiguously discriminate between open water areas and ponded floes. Coincident active multichannel microwave radiometer and SAR measurements of individual floes are used to describe the effects of surface melt on sea ice concentration calculations.

  17. Efficiency calibration and minimum detectable activity concentration of a real-time UAV airborne sensor system with two gamma spectrometers.

    PubMed

    Tang, Xiao-Bin; Meng, Jia; Wang, Peng; Cao, Ye; Huang, Xi; Wen, Liang-Sheng; Chen, Da

    2016-04-01

    A small-sized UAV (NH-UAV) airborne system with two gamma spectrometers (LaBr3 detector and HPGe detector) was developed to monitor activity concentration in serious nuclear accidents, such as the Fukushima nuclear accident. The efficiency calibration and determination of minimum detectable activity concentration (MDAC) of the specific system were studied by MC simulations at different flight altitudes, different horizontal distances from the detection position to the source term center and different source term sizes. Both air and ground radiation were considered in the models. The results obtained may provide instructive suggestions for in-situ radioactivity measurements of NH-UAV. PMID:26773821

  18. Short-term 222Rn activity concentration changes in underground spaces with limited air exchange with the atmosphere

    NASA Astrophysics Data System (ADS)

    Fijałkowska-Lichwa, L.; Przylibski, T. A.

    2011-04-01

    The authors investigated short-time changes in 222Rn activity concentration occurring yearly in two underground tourist facilities with limited air exchange with the atmosphere. One of them is Niedźwiedzia (Bear) Cave in Kletno, Poland - a natural space equipped with locks ensuring isolation from the atmosphere. The other site is Fluorite Adit in Kletno, a section of a disused uranium mine. This adit is equipped with a mechanical ventilation system, operated periodically outside the opening times (at night). Both sites are situated within the same metamorphic rock complex, at similar altitudes, about 2 km apart. The measurements conducted revealed spring and autumn occurrence of convective air movements. In Bear Cave, this process causes a reduction in 222Rn activity concentration in the daytime, i.e. when tourists, guides and other staff are present in the cave. From the point of view of radiation protection, this is the best situation. For the rest of the year, daily concentrations of 222Rn activity in the cave are very stable. In Fluorite Adit, on the other hand, significant variations in daily 222Rn activity concentrations are recorded almost all year round. These changes are determined by the periods of activity and inactivity of mechanical ventilation. Unfortunately this is inactive in the daytime, which results in the highest values of 222Rn activity concentration at the times when tourists and staff are present in the adit. Slightly lower concentrations of radon in Fluorite Adit are recorded in the winter season, when convective air movements carry a substantial amount of radon out into the atmosphere. The incorrect usage of mechanical ventilation in Fluorite Adit results in the most unfavourable conditions in terms of radiation protection. The staff working in that facility are exposed practically throughout the year to the highest 222Rn activity concentrations, both at work (in the adit) and at home (outside their working hours). Therefore, not very well

  19. 40K- 40Ar dating of the Main Deccan large igneous province: Further evidence of KTB age and short duration

    NASA Astrophysics Data System (ADS)

    Chenet, Anne-Lise; Quidelleur, Xavier; Fluteau, Frédéric; Courtillot, Vincent; Bajpai, Sunil

    2007-11-01

    Most mass extinctions coincide in time with outpourings of continental flood basalts (CFB). Some 20 years ago, it was shown [Courtillot, V., Besse, J., Vandamme, D., Montigny, R., Jaeger, J.-J., Cappetta, H., 1986. Deccan flood basalts at the Cretaceous/Tertiary boundary? Earth Planet. Sci. Lett. 80, 361-374; Courtillot, V., Feraud, G., Maluski, H., Vandamme, D., Moreau, M.G., Besse, J., 1988. Deccan flood basalts and the Cretaceous/Tertiary boundary. Nature 333, 843-846; Duncan, R.A., Pyle, D.G., 1988. Rapid eruption of the Deccan flood basalts at the Cretaceous/Tertiary boundary. Nature 333 841-843] that the age of the Deccan traps was close to the Cretaceous-Tertiary (KT) boundary and its duration under 1 Myr. We have undertaken a new geochronological study, using the (unconventional) 40K- 40Ar Cassignol-Gillot technique which is particularly well suited to the potassium-poor Deccan lavas. The mean of 4 determinations from the topmost (Ambenali and Mahabaleshwar) Formations is 64.5 ± 0.6 Ma. They straddle the C29r/C29n reversal boundary for which they provide a new constraint. The mean age of 3 determinations from the oldest (Jawhar) Formation is 64.8 ± 0.6 Ma. The difference in age between top and bottom of a 3500 m composite section, probably comprising 80% of the total Deccan volume, is statistically insignificant, with the overall mean age being 64.7 ± 0.6 Ma ( N = 7). Our results are consistent with the most recent 40Ar/ 39Ar determinations [Knight, K.B., Renne, P.R., Halkett, A., White, N., 2003. 40Ar/ 39Ar dating of the Rajahmundry Traps, eastern India and their relationship to the Deccan traps. Earth Planet. Sci. Lett. 208, 85-99; Knight, K.B., Renne, P.R., Baker, J., Waight, T., White, N., 2005. Reply to '40Ar/39Ar dating of the Rajahmundry Traps, Eastern India and their relationship to the Deccan Traps: Discussion' by A.K. Baksi. Earth Planet. Sci. Lett. 239, 374-382], confirming that there should be no systematic difference between the two methods

  20. Immobilized Hydrolytic Enzymes Exhibit Antibiofilm Activity Against Escherichia coli at Sub-Lethal Concentrations.

    PubMed

    Villa, Federica; Secundo, Francesco; Polo, Andrea; Cappitelli, Francesca

    2015-07-01

    The effects of two commercially available immobilized enzymes (namely the glycosidase pectinase and the protease subtilisin A) at sub-lethal concentrations were investigated in terms of their influence on biofilm genesis, on the composition of the biofilm matrix, and their antibiotic synergy against Escherichia coli biofilm, used as a model system of bacterial biofilms. The best antibiofilm performance of solid-supported hydrolases was obtained at the surface concentration of 0.022 and 0.095 U/cm(2) with a reduction of 1.2 and 2.3 log CFU/biofilm for pectinase and subtilisin, respectively. At these enzyme surface concentrations, the biocatalysts affected the structural composition of the biofilm matrix, impacting biofilm thickness. Finally, the immobilized hydrolases enhanced biofilm sensitivity to a clinically relevant concentration of the antibiotic ampicillin. At the final antibiotic concentration of 0.1 mg/ml, a reduction of 2 and 3.5 log10 units in presence of 0.022 Upectinase/cm(2) and 0.095 Usubtilisin/cm(2) was obtained, respectively, in comparison the antibiotic alone. Immobilized pectinase and subtilisin at sub-lethal concentrations demonstrated a great potential for antibiofilm applications. PMID:25958074

  1. Application of acid-activated Bauxsol for wastewater treatment with high phosphate concentration: Characterization, adsorption optimization, and desorption behaviors.

    PubMed

    Ye, Jie; Cong, Xiangna; Zhang, Panyue; Zeng, Guangming; Hoffmann, Erhard; Liu, Yang; Wu, Yan; Zhang, Haibo; Fang, Wei; Hahn, Hermann H

    2016-02-01

    Acid-activated Bauxsol was applied to treat wastewater with high phosphate concentration in a batch adsorption system in this paper. The effect of acid activation on the change of Bauxsol structure was systematically investigated. The mineralogical inhomogeneity and intensity of Bauxsol decreased after acid activation, and FeCl3·2H2O and Al(OH)3 became the dominant phases of acid-activated Bauxsol adsorption. Moreover, the BET surface area and total pore volume of Bauxsol increased after acid activation. Interaction of initial solution pH and adsorption temperature on phosphate adsorption onto acid-activated Bauxsol was investigated by using response surface methodology with central composite design. The maximum phosphate adsorption capacity of 192.94 mg g(-1) was achieved with an initial solution pH of 4.19 and an adsorption temperature of 52.18 °C, which increased by 7.61 times compared with that of Bauxsol (22.40 mg g(-1)), and was higher than other adsorbents. Furthermore, the desorption studies demonstrated that the acid-activated Bauxsol was successfully regenerated with 0.5 mol L(-1) HCl solution. The adsorption capacity and desorption efficiency of acid-activated Bauxsol maintained at 80.48% and 93.02% in the fifth adsorption-desorption cycle, respectively, suggesting that the acid-activated Bauxsol could be repeatedly used in wastewater treatment with high phosphate concentration. PMID:26606195

  2. Effect of nano-zinc oxide on nitrogenase activity in legumes: an interplay of concentration and exposure time

    NASA Astrophysics Data System (ADS)

    Kumar, Praveen; Burman, Uday; Santra, P.

    2015-07-01

    Experiments were carried out to study the effect of zinc oxide nanoparticles (nano-ZnO) on nitrogenase activity in legumes. In the first experiment, nodulated roots of cluster bean, moth bean, green gram and cowpea were dipped in Hoagland solution containing 1.5 and 10 μg mL-1 of nano-ZnO for 24 h. Nitrogenase activity in cluster bean, green gram and cowpea roots increased after dipping in solution containing 1.5 μg mL-1 nano-ZnO, but decreased in roots dipped in solution containing 10 μg mL-1 nano-ZnO. However, in moth bean roots, nitrogenase activity decreased after dipping in solution containing either concentration of nano-ZnO. In the second experiment, nodulated roots of green gram were dipped in Hoagland solution containing 1, 4, 6, 8 and 10 μg mL-1 nano-ZnO for 6-30 h before estimating nitrogenase activity. Results showed that an interactive effect of nano-ZnO concentration and exposure time influenced nitrogenase activity. The possible reasons behind this effect have been discussed. A model [ A = 3.44 + 0.46 t - 0.01 t 2 - 0.002 tc 2 ( R 2 = 0.81)] involving linear and power components was developed to simulate the response of nitrogenase activity in green gram roots to the concentration and exposure time of nano-ZnO.

  3. Nanoscale Concentration Quantification of Pharmaceutical Actives in Amorphous Polymer Matrices by Electron Energy-Loss Spectroscopy.

    PubMed

    Ricarte, Ralm G; Lodge, Timothy P; Hillmyer, Marc A

    2016-07-26

    We demonstrated the use of electron energy-loss spectroscopy (EELS) to evaluate the composition of phenytoin:hydroxypropyl methylcellulose acetate succinate (HPMCAS) spin-coated solid dispersions (SDs). To overcome the inability of bright-field and high-angle annular dark-field TEM imaging to distinguish between glassy drug and polymer, we used the π-π* transition peak in the EELS spectrum to detect phenytoin within the HPMCAS matrix of the SD. The concentration of phenytoin within SDs of 10, 25, and 50 wt % drug loading was quantified by a multiple least-squares analysis. Evaluating the concentration of 50 different regions in each SD, we determined that phenytoin and HPMCAS are intimately mixed at a length scale of 200 nm, even for drug loadings up to 50 wt %. At length scales below 100 nm, the variance of the measured phenytoin concentration increases; we speculate that this increase is due to statistical fluctuations in local concentration and chemical changes induced by electron irradiation. We also performed EELS analysis of an annealed 25 wt % phenytoin SD and showed that the technique can resolve concentration differences between regions that are less than 50 nm apart. Our findings indicate that EELS is a useful tool for quantifying, with high accuracy and sub-100 nm spatial resolution, the composition of many pharmaceutical and soft matter systems. PMID:27419264

  4. Effect of chloroethene concentrations and granular activated carbon on reductive dechlorination rates and growth of Dehalococcoides spp.

    PubMed

    Aktaş, Özgür; Schmidt, Kathrin R; Mungenast, Sarah; Stoll, Claudia; Tiehm, Andreas

    2012-01-01

    This study focused on the investigation of (i) the tetrachloroethene (PCE) toxicity threshold of a reductively dechlorinating mixed culture containing Dehalococcoides spp., (ii) the adsorption of PCE on different types of granular activated carbon (GAC), and (iii) the bioavailability and reductive dechlorination in the presence of GAC. The abundance of Dehalococcoides spp. detected by quantitative real-time polymerase chain reaction (qPCR) was found to increase by 2-4 orders of magnitude during degradation of PCE. No degradation occurred at dissolved concentrations beyond 420 μM (70 mg/L). Different adsorption isotherms were determined for thermally and chemically activated carbons. The addition of GAC to biological assays reduced the dissolved PCE concentration below the toxicity threshold. The combination of microbial reductive dechlorination with GAC adsorption proved to be a promising method for remediation of groundwater contaminated by high concentrations of chloroethenes. PMID:22044603

  5. Strontium-90 activity concentration in soil samples from the exclusion zone of the Fukushima daiichi nuclear power plant.

    PubMed

    Sahoo, Sarata Kumar; Kavasi, Norbert; Sorimachi, Atsuyuki; Arae, Hideki; Tokonami, Shinji; Mietelski, Jerzy Wojciech; Łokas, Edyta; Yoshida, Satoshi

    2016-01-01

    The radioactive fission product (90)Sr has a long biological half-life (˜18 y) in the human body. Due to its chemical similarity to calcium it accumulates in bones and irradiates the bone marrow, causing its high radio-toxicity. Assessing (90)Sr is therefore extremely important in case of a nuclear disaster. In this work 16 soil samples were collected from the exclusion zone (<30 km) of the earthquake-damaged Fukushima Daiichi nuclear power plant, to measure (90)Sr activity concentration using liquid scintillation counting. (137)Cs activity concentration was also measured with gamma-spectroscopy in order to investigate correlation with (90)Sr. The (90)Sr activity concentrations ranged from 3.0 ± 0.3 to 23.3 ± 1.5 Bq kg(-1) while the (137)Cs from 0.7 ± 0.1 to 110.8 ± 0.3 kBq kg(-1). The fact that radioactive contamination originated from the Fukushima nuclear accident was obvious due to the presence of (134)Cs. However, (90)Sr contamination was not confirmed in all samples although detectable amounts of (90)Sr can be expected in Japanese soils, as a background, stemming from global fallout due to the atmospheric nuclear weapon tests. Correlation analysis between (90)Sr and (137)Cs activity concentrations provides a potentially powerful tool to discriminate background (90)Sr level from its Fukushima contribution. PMID:27048779

  6. Effect of Hofmeister anions and protein concentration on the activity and stability of some immobilized made-independent dehydrogenases

    SciTech Connect

    Carrea, G.; Bovara, R.; Pasta, P.; Cremonesi, P.

    1982-01-01

    The effect of several factors on the activity and stability of alcohol dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase, and 20-beta-hydroxysteroid dehydrogenase, both free and immobilized on CNBr-activated Sepharose 4B, was investigated. Enzymes were immobilized under different conditions including various degrees of matrix activation, variable amounts of protein, in the presence, or in the absence of, additives (coenzymes, dithiothreitol, salts). Activity recovery was in general satisfactorily high with 20-beta-hydroxysteroid dehydrogenase, low with glyceraldehyde-3-phosphate dehydrogenase, and markedly linked to the concentration of immobilized protein with alcohol dehydrogenase. In the latter case the advantageous stabilizing effect of high enzyme concentrations was notably diminished by the paralled decrease of the effectiveness factor. The effect of high concentrations of anions of the Hofmeister series was examined. It was found that 1M phosphate and 0.5M sulfate dramatically stabilize both free and immobilized enzymes against inactivation by temperature and urea. Km values of apolar substrates were considerably lowered by the two anions while Km values of polar substrates were not affected. In some cases Vmax values also were influenced by high concentrations of these anions. The present results appear of interest particularly in view of enzyme utilization for analytical as well as for preparative purposes. (Refs. 13).

  7. Strontium-90 activity concentration in soil samples from the exclusion zone of the Fukushima daiichi nuclear power plant

    NASA Astrophysics Data System (ADS)

    Sahoo, Sarata Kumar; Kavasi, Norbert; Sorimachi, Atsuyuki; Arae, Hideki; Tokonami, Shinji; Mietelski, Jerzy Wojciech; Łokas, Edyta; Yoshida, Satoshi

    2016-04-01

    The radioactive fission product 90Sr has a long biological half-life (˜18 y) in the human body. Due to its chemical similarity to calcium it accumulates in bones and irradiates the bone marrow, causing its high radio-toxicity. Assessing 90Sr is therefore extremely important in case of a nuclear disaster. In this work 16 soil samples were collected from the exclusion zone (<30 km) of the earthquake-damaged Fukushima Daiichi nuclear power plant, to measure 90Sr activity concentration using liquid scintillation counting. 137Cs activity concentration was also measured with gamma-spectroscopy in order to investigate correlation with 90Sr. The 90Sr activity concentrations ranged from 3.0 ± 0.3 to 23.3 ± 1.5 Bq kg‑1 while the 137Cs from 0.7 ± 0.1 to 110.8 ± 0.3 kBq kg‑1. The fact that radioactive contamination originated from the Fukushima nuclear accident was obvious due to the presence of 134Cs. However, 90Sr contamination was not confirmed in all samples although detectable amounts of 90Sr can be expected in Japanese soils, as a background, stemming from global fallout due to the atmospheric nuclear weapon tests. Correlation analysis between 90Sr and 137Cs activity concentrations provides a potentially powerful tool to discriminate background 90Sr level from its Fukushima contribution.

  8. Impacts of land-applying class B municipal biosolids on soil microbial activity and soil nutrient and metal concentrations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Impacts of land-applying Class B biosolids on microbial activities and nutrient and metal concentrations in surface soils (0-10 cm) of coastal bermudagrass fields were measured during a 112-day incubation. Application rates were: control, 22, 45, and 67 dry Mg biosolids ha-1 y-1 for 8 years and 22 ...

  9. Effects of Hatha yoga exercise on plasma malondialdehyde concentration and superoxide dismutase activity in female patients with shoulder pain

    PubMed Central

    Ha, Min-Sung; Kim, Do-Yeon; Baek, Yeong-Ho

    2015-01-01

    [Purpose] The purpose of this study was to analyze the effects of Hatha yoga exercise on plasma malondialdehyde (MDA) concentration and superoxide dismutase (SOD) activity in female patients with shoulder pain. [Subjects] Subjects comprised 20 female patients with shoulder pain. [Methods] Subjects were divided into 2 groups: a Hatha yoga exercise group (n = 10) and a control group that performed no exercise (n = 10). The subjects’ body composition, plasma malondialdehyde concentrations, and superoxide dismutase activities were measured before and after a 16-week Hatha yoga exercise program. [Results] After the 16-week Hatha yoga exercise program, the exercise group had significantly lower plasma MDA concentrations than the control group. In addition, the exercise group had significantly higher plasma SOD activity than the control group. [Conclusions] Hatha yoga exercise improves flexibility, muscle tone and strength, balance, and joint function. Our findings indicate that regular and continuous yoga exercise effectively improved body composition, decrease plasma MDA concentration, and increase plasma SOD activity in female patients with shoulder pain. PMID:26311934

  10. Strontium-90 activity concentration in soil samples from the exclusion zone of the Fukushima daiichi nuclear power plant

    PubMed Central

    Sahoo, Sarata Kumar; Kavasi, Norbert; Sorimachi, Atsuyuki; Arae, Hideki; Tokonami, Shinji; Mietelski, Jerzy Wojciech; Łokas, Edyta; Yoshida, Satoshi

    2016-01-01

    The radioactive fission product 90Sr has a long biological half-life (˜18 y) in the human body. Due to its chemical similarity to calcium it accumulates in bones and irradiates the bone marrow, causing its high radio-toxicity. Assessing 90Sr is therefore extremely important in case of a nuclear disaster. In this work 16 soil samples were collected from the exclusion zone (<30 km) of the earthquake-damaged Fukushima Daiichi nuclear power plant, to measure 90Sr activity concentration using liquid scintillation counting. 137Cs activity concentration was also measured with gamma-spectroscopy in order to investigate correlation with 90Sr. The 90Sr activity concentrations ranged from 3.0 ± 0.3 to 23.3 ± 1.5 Bq kg−1 while the 137Cs from 0.7 ± 0.1 to 110.8 ± 0.3 kBq kg−1. The fact that radioactive contamination originated from the Fukushima nuclear accident was obvious due to the presence of 134Cs. However, 90Sr contamination was not confirmed in all samples although detectable amounts of 90Sr can be expected in Japanese soils, as a background, stemming from global fallout due to the atmospheric nuclear weapon tests. Correlation analysis between 90Sr and 137Cs activity concentrations provides a potentially powerful tool to discriminate background 90Sr level from its Fukushima contribution. PMID:27048779

  11. Liquid scintillation counting of polycarbonates: a sensitive technique for measurement of activity concentration of some radioactive noble gases.

    PubMed

    Mitev, K; Zhivkova, V; Pressyanov, D; Georgiev, S; Dimitrova, I; Gerganov, G; Boshkova, T

    2014-11-01

    This work explores the application of the liquid scintillation counting of polycarbonates for measurement of the activity concentration of radioactive noble gases. Results from experimental studies of the method are presented. Potential applications in the monitoring of radioactive noble gases are discussed. PMID:24559941

  12. Activity concentrations of 222Rn, 220Rn, and their decay products in german dwellings, dose calculations and estimate of risk.

    PubMed

    Keller, G; Folkerts, K H; Muth, H

    1982-01-01

    Measurements of the concentrations of 222Rn, its short-lived decay products and of 212Pb - 212Bi were performed in 150 dwellings and in the open air in the Federal Republic of Germany. The concentrations of 222Rn was measured by electrostatic deposition of 218Po. The concentration of the short-lived decay products were measured by air sampling and alpha-spectroscopy. It was found that inside dwellings the average potential alpha-energy concentration of the short-lived daughters is about three times higher than in the open air. The total potential alpha-energy concentration indoors amounts to 2.6 . 10(-3) Working Level (W.L.). Direct measurements of the equilibrium factor inside dwellings gave a mean value of 0.3. A strong dependence of the potential alpha energy concentration on the ventilation rate in dwellings has been observed. These ventilation effects exceed the effects caused by differences in the activity concentrations due to different building materials. The dose calculation results in an average dose to the whole lung due to the inhalation of short-lived radon daughters of about 0.05-0.2 m/Gy/a. An estimate of risk - based on the risk factors for uranium miners - shows an average lifetime risk of about 6 . 10(-4) for the incidence of lung cancer caused by inhalation of radon and thoron daughters in dwellings in the Federal Republic of Germany. PMID:7146318

  13. The activity concentration of 210Po in Romanian commercial cigarettes and the radiation exposure estimation derived from their regular consumption.

    PubMed

    Begy, R Cs; Somlai, J; Kovacs, T; Dumitru Rusu, O A; Cosma, C

    2013-11-01

    Due to the relatively high activity concentrations of (210)Po that are found in tobacco, cigarette smoking has been found to be the principal pathway of the intake of this radionuclide. The (210)Po concentrations in the lung tissues may contribute significantly to an increase in the internal radiation dose and in the number of instances of lung cancer observed among smokers. The study of (210)Po in tobacco is required due to its potential for human radiation exposure through ingestion and inhalation. The risk factor caused by (210)Po in Romanian commercial cigarettes is not yet evaluated. Ten of the most frequently smoked brands of cigarettes sold in Romania were investigated in this work for this purpose. The activity concentration of (210)Po was determined by alpha spectrometry using a PIPS detector after chemical leaching and spontaneous deposition of (210)Po on a stainless steel disc from diluted HCl solution. The samples were spiked with (209)Po for chemical recovery calculation. The (210)Po activity concentrations of the measured types of cigarettes ranged from 4.65 to 10.22 mBq sample(-1) and the resulted average concentration of (210)Po isotopes is 8.35±0.80 mBq cigarette(-1) (the errors form a 2σ interval of confidence). When comparing the results of this study with the activity concentration values reported by other countries it was found that the results of this study are in the lower end of the world range. The estimation of this study shows that cigarette smokers, who are smoking one pack (20 cigarettes) per day, are exposed to an effective dose of 75.51 μSv y(-1). PMID:23651657

  14. Ultraviolet irradiation of platelet concentrate abrogates lymphocyte activation without affecting platelet function in vitro

    SciTech Connect

    Kahn, R.A.; Duffy, B.F.; Rodey, G.G.

    1985-11-01

    We studied the effect of ultraviolet (UV) radiation on platelet concentrates. Samples irradiated at 310 mm for 30 minutes at a dose of 1782 J per m2 showed no loss of platelet function in vitro as determined by adenosine diphosphate, collagen, or ristocetin-induced aggregation. Lymphocytes isolated from irradiated units were unable to act as responders or stimulators in a mixed-lymphocyte reaction. These data suggest that UV radiation of platelet concentrates may result in a cell suspension that is unable to evoke an immunological response.

  15. Changes in the activities of starch metabolism enzymes in rice grains in response to elevated CO2 concentration

    NASA Astrophysics Data System (ADS)

    Xie, Li-Yong; Lin, Er-Da; Zhao, Hong-Liang; Feng, Yong-Xiang

    2016-05-01

    The global atmospheric CO2 concentration is currently (2012) 393.1 μmol mol-1, an increase of approximately 42 % over pre-industrial levels. In order to understand the responses of metabolic enzymes to elevated CO2 concentrations, an experiment was conducted using the Free Air CO2 Enrichment (FACE )system. Two conventional japonica rice varieties ( Oryza sativa L. ssp. japonica) grown in North China, Songjing 9 and Daohuaxiang 2, were used in this study. The activities of ADPG pyrophosphorylase, soluble and granule-bound starch synthases, and soluble and granule-bound starch branching enzymes were measured in rice grains, and the effects of elevated CO2 on the amylose and protein contents of the grains were analyzed. The results showed that elevated CO2 levels significantly increased the activity of ADPG pyrophosphorylase at day 8, 24, and 40 after flower, with maximum increases of 56.67 % for Songjing 9 and 21.31 % for Daohuaxiang 2. Similarly, the activities of starch synthesis enzymes increased significantly from the day 24 after flower to the day 40 after flower, with maximum increases of 36.81 % for Songjing 9 and 66.67 % for Daohuaxiang 2 in soluble starch synthase (SSS), and 25.00 % for Songjing 9 and 36.44 % for Daohuaxiang 2 in granule-bound starch synthase (GBSS), respectively. The elevated CO2 concentration significantly increased the activity of soluble starch branching enzyme (SSBE) at day 16, 32, and 40 after flower, and also significantly increased the activity of granule-bound starch branching enzyme (GBSBE) at day 8, 32, and 40 after flower. The elevated CO2 concentration increased the peak values of enzyme activity, and the timing of the activity peaks for SSS and GBSBE were earlier in Songjing 9 than in Daohuaxiang 2. There were obvious differences in developmental stages between the two varieties of rice, which indicated that the elevated CO2 concentration increased enzyme activity expression and starch synthesis, affecting the final contents

  16. Changes in the activities of starch metabolism enzymes in rice grains in response to elevated CO2 concentration.

    PubMed

    Xie, Li-Yong; Lin, Er-Da; Zhao, Hong-Liang; Feng, Yong-Xiang

    2016-05-01

    The global atmospheric CO(2) concentration is currently (2012) 393.1 μmol mol(-1), an increase of approximately 42 % over pre-industrial levels. In order to understand the responses of metabolic enzymes to elevated CO(2) concentrations, an experiment was conducted using the Free Air CO(2) Enrichment (FACE )system. Two conventional japonica rice varieties (Oryza sativa L. ssp. japonica) grown in North China, Songjing 9 and Daohuaxiang 2, were used in this study. The activities of ADPG pyrophosphorylase, soluble and granule-bound starch synthases, and soluble and granule-bound starch branching enzymes were measured in rice grains, and the effects of elevated CO(2) on the amylose and protein contents of the grains were analyzed. The results showed that elevated CO(2) levels significantly increased the activity of ADPG pyrophosphorylase at day 8, 24, and 40 after flower, with maximum increases of 56.67 % for Songjing 9 and 21.31 % for Daohuaxiang 2. Similarly, the activities of starch synthesis enzymes increased significantly from the day 24 after flower to the day 40 after flower, with maximum increases of 36.81 % for Songjing 9 and 66.67 % for Daohuaxiang 2 in soluble starch synthase (SSS), and 25.00 % for Songjing 9 and 36.44 % for Daohuaxiang 2 in granule-bound starch synthase (GBSS), respectively. The elevated CO(2) concentration significantly increased the activity of soluble starch branching enzyme (SSBE) at day 16, 32, and 40 after flower, and also significantly increased the activity of granule-bound starch branching enzyme (GBSBE) at day 8, 32, and 40 after flower. The elevated CO(2) concentration increased the peak values of enzyme activity, and the timing of the activity peaks for SSS and GBSBE were earlier in Songjing 9 than in Daohuaxiang 2. There were obvious differences in developmental stages between the two varieties of rice, which indicated that the elevated CO(2) concentration increased enzyme activity expression and starch synthesis, affecting the

  17. Tritium activity concentrations and residence times of groundwater collected in Rokkasho, Japan.

    PubMed

    Hasegawa, Hidenao; Ueda, Shinji; Akata, Naofumi; Kakiuchi, Hideki; Hisamatsu, Shun'ichi

    2015-11-01

    Tritium ((3)H) concentrations were measured in groundwater samples from four surface wells (4-10 m deep), four shallow wells (24-26.5 m deep) and a 150-m-deep well in the Futamata River catchment area, which is adjacent to the large-scale commercial spent nuclear fuel reprocessing plant in Rokkasho, Japan. The (3)H concentrations in most of the surface- and shallow-well samples (<0.03-0.57 Bq l(-1)) were similar to those in precipitation (annual mean: 0.31-0.79 Bq l(-1)), suggesting that the residence time of the water in those wells was 0-15 y. The (3)H concentrations in the samples from a 26-m-deep well and the 150-m-deep well were lower than those in the other wells, indicating that groundwater with a long residence time exists in deep aquifers and the estuary area of the catchment. It is not clear whether (3)H released during test operation of the plant with actual spent nuclear fuel affected the (3)H concentrations observed in this study. PMID:25944959

  18. Caffeine-induced increase in voluntary activation and strength of the quadriceps muscle during isometric, concentric and eccentric contractions.

    PubMed

    Behrens, Martin; Mau-Moeller, Anett; Weippert, Matthias; Fuhrmann, Josefin; Wegner, Katharina; Skripitz, Ralf; Bader, Rainer; Bruhn, Sven

    2015-01-01

    This study investigated effects of caffeine ingestion (8 mg/kg) on maximum voluntary torque (MVT) and voluntary activation of the quadriceps during isometric, concentric and eccentric contractions. Fourteen subjects ingested caffeine and placebo in a randomized, controlled, counterbalanced, double-blind crossover design. Neuromuscular tests were performed before and 1 h after oral caffeine and placebo intake. MVTs were measured and the interpolated twitch technique was applied during isometric, concentric and eccentric contractions to assess voluntary activation. Furthermore, normalized root mean square of the EMG signal was calculated and evoked spinal reflex responses (H-reflex evoked at rest and during weak isometric voluntary contraction) as well as twitch torques were analyzed. Caffeine increased MVT by 26.4 N m (95%CI: 9.3-43.5 N m, P = 0.004), 22.5 N m (95%CI: 3.1-42.0 N m, P = 0.025) and 22.5 N m (95%CI: 2.2-42.7 N m, P = 0.032) for isometric, concentric and eccentric contractions. Strength enhancements were associated with increases in voluntary activation. Explosive voluntary strength and voluntary activation at the onset of contraction were significantly increased following caffeine ingestion. Changes in spinal reflex responses and at the muscle level were not observed. Data suggest that caffeine ingestion induced an acute increase in voluntary activation that was responsible for the increased strength regardless of the contraction mode. PMID:25969895

  19. Effect of Sodium Fluoride Ingestion on Malondialdehyde Concentration and the Activity of Antioxidant Enzymes in Rat Erythrocytes

    PubMed Central

    Morales-González, José A.; Gutiérrez-Salinas, José; García-Ortiz, Liliana; del Carmen Chima-Galán, María; Madrigal-Santillán, Eduardo; Esquivel-Soto, Jaime; Esquivel-Chirino, César; González-Rubio, Manuel García-Luna y

    2010-01-01

    Fluoride intoxication has been shown to produce diverse deleterious metabolic alterations within the cell. To determine the effects of sodium fluoride (NaF) treatment on malondialdehyde (MDA) levels and on the activity of antioxidant enzymes in rat erythrocytes, Male Wistar rats were treated with 50 ppm of NaF or were untreated as controls. Erythrocytes were obtained from rats sacrificed weekly for up to eight weeks and the concentration of MDA in erythrocyte membrane was determined. In addition, the activity of the enzymes superoxide, dismutase, catalase, and glutathione peroxidase were determined. Treatment with NaF produces an increase in the concentration of malondialdehyde in the erythrocyte membrane only after the eight weeks of treatment. On the other hand, antioxidant enzyme activity was observed to increase after the fourth week of NaF treatment. In conclusion, intake of NaF produces alterations in the erythrocyte of the male rat, which indicates induction of oxidative stress. PMID:20640162

  20. EROD activity and genotoxicity in the seabob shrimp Xiphopenaeus kroyeri exposed to benzo[a]pyrene (BaP) concentrations.

    PubMed

    da Silva Rocha, Arthur José; Gomes, Vicente; Rocha Passos, Maria José de Arruda Campos; Hasue, Fabio Matsu; Alves Santos, Thaís Cruz; Bícego, Márcia Caruso; Taniguchi, Satie; Van Ngan, Phan

    2012-11-01

    Seabob shrimp Xiphopenaeus kroyeri is a marine species that lives in shallow waters of coastal environments, often impacted by polycyclic aromatic hydrocarbons (PAH) pollution. In the present study, seabob shrimp were exposed for 96 h to benzo[a]pyrene (BaP) at the nominal concentrations of 100, 200, 400 and 800 microg-L(-1). Animals of the control groups were exposed either to clean water or to the BaP-carrier (DMSO). At the end of the exposures, muscle tissues were sampled for BaP uptake assessment and hepatopancreas and hemolymph for EROD enzyme activity and hemocytes DNA damage, respectively. EROD activity and DNA damage increased significantly as a function of BaP exposure concentrations. Significant correlations between BaP uptake and both EROD activity and DNA damage suggest that they can be used as suitable tools for integrated levels of study on the biomarkers of PAH exposure. PMID:22974795

  1. Measurement of natural and 137Cs radioactivity concentrations at Izmit Bay (Marmara Sea), Turkey

    NASA Astrophysics Data System (ADS)

    Öksüz, I.; Güray, R. T.; Özkan, N.; Yalçin, C.; Ergül, H. A.; Aksan, S.

    2016-03-01

    In order to determine the radioactivity level at Izmit Bay Marmara Sea, marine sediment samples were collected from five different locations. The radioactivity concentrations of naturally occurring 238U, 232Th and 40K isotopes and also that of an artificial isotope 137Cs were measured by using gamma-ray spectroscopy. Preliminary results show that the radioactivity concentrations of 238U and 232Th isotopes are lower than the average worldwide values while the radioactivity concentrations of the 40K are higher than the average worldwide value. A small amount of 137Cs contamination, which might be caused by the Chernobyl accident, was also detected.

  2. Analysis of the 40K contamination in NaI(Tl) crystals from different providers in the frame of the ANAIS project

    NASA Astrophysics Data System (ADS)

    Cuesta, C.; Amaré, J.; Cebrián, S.; García, E.; Ginestra, C.; Martínez, M.; Oliván, M. A.; Ortigoza, Y.; Ortiz de Solórzano, A.; Pobes, C.; Puimedón, J.; Sarsa, M. L.; Villar, J. A.; Villar, P.

    2014-07-01

    NaI(Tl) large crystals are applied in the search for galactic dark matter particles through their elastic scattering off the target nuclei in the detector by measuring the scintillation signal produced. However, energies deposited in the form of nuclear recoils are small, which added to the low efficiency to convert that energy into scintillation, makes that events at or very near the energy threshold, attributed either to radioactive backgrounds or to spurious noise (nonbulk NaI(Tl) scintillation events), can compromise the sensitivity goals of such an experiment. DAMA/LIBRA experiment, using 250 kg NaI(Tl) target, reported first evidence of the presence of an annual modulation in the detection rate compatible with that expected for a dark matter signal just in the region below 6 keVee (electron equivalent energy). In the frame of the ANAIS (Annual modulation with NaI Scintillators) dark matter search project a large and long effort has been carried out in order to understand the origin of events at very low energy in large sodium iodide detectors and develop convenient filters to reject those nonattributable to scintillation in the bulk NaI(Tl) crystal. 40K is probably the most relevant radioactive contaminant in the bulk for NaI(Tl) detectors because of its important contribution to the background at very low energy. ANAIS goal is to achieve levels at or below 20 ppb natural potassium. In this paper we will report on our effort to determine the 40K contamination in several NaI(Tl) crystals, by measuring in coincidence between two (or more) of them. Results obtained for the 40K content of crystals from different providers will be compared and prospects of the ANAIS dark matter search experiment will be briefly reviewed.

  3. Development of semi-automated system for preparation of (188)Re aqueous solutions of high and reproducible activity concentrations.

    PubMed

    Jäckel, B; Cripps, R; Güntay, S; Bruchertseifer, H

    2005-09-01

    A semi-automated system has been developed for elution and concentration of the (188)Re-eluate from 111 GBq (3 Ci) (188)W/(188)Re-generators to provide a dissolved beta-source of high (188)Re-activity per unit volume. The elution progress and concentration were precisely and continuously monitored by use of collimated diode detectors. By using ion exchange cartridges, small eluate volumes (2-3 ml) of maximum 40 GBq, (188)Re/ml activity concentration were routinely prepared. The concentrated (188)Re solutions were used to beta-irradiate aqueous suspensions and solutions of iodine species to evaluate a simulation of the extent of radiolytic decomposition of chemical species (AgI and CH(3)I) expected to accumulate in the containment sump of a nuclear reactor in the event of a severe accident with reproducible dose rates of up to 0.4 Gys(-1). Results have shown that AgI colloidal particles decompose to varying extents, depending on conditions, and in proportion to their initial mass, which indicates surface oxidation. Experiments have also confirmed CH(3)I decomposition in proportion to initial aqueous concentration. PMID:15963728

  4. EVALUATION OF AIRBORNE ASBESTOS CONCENTRATIONS BEFORE AND DURING AND O&M ACTIVITY: A CASE STUDY

    EPA Science Inventory

    The current lack of information regarding the impact of O&M activities on the potential for asbestos exposure to building staff and occupants prompted this study. This report presents a statistical evaluation of airborne asbestos data collected before and during an O&M activity i...

  5. Coupling of total hemoglobin concentration, oxygenation, and neural activity in rat somatosensory cortex.

    PubMed

    Devor, Anna; Dunn, Andrew K; Andermann, Mark L; Ulbert, Istvan; Boas, David A; Dale, Anders M

    2003-07-17

    Recent advances in brain imaging techniques, including functional magnetic resonance imaging (fMRI), offer great promise for noninvasive mapping of brain function. However, the indirect nature of the imaging signals to the underlying neural activity limits the interpretation of the resulting maps. The present report represents the first systematic study with sufficient statistical power to quantitatively characterize the relationship between changes in blood oxygen content and the neural spiking and synaptic activity. Using two-dimensional optical measurements of hemodynamic signals, simultaneous recordings of neural activity, and an event-related stimulus paradigm, we demonstrate that (1) there is a strongly nonlinear relationship between electrophysiological measures of neuronal activity and the hemodynamic response, (2) the hemodynamic response continues to grow beyond the saturation of electrical activity, and (3) the initial increase in deoxyhemoglobin that precedes an increase in blood volume is counterbalanced by an equal initial decrease in oxyhemoglobin. PMID:12873390

  6. Relationships between environmental organochlorine contaminant residues, plasma corticosterone concentrations, and intermediary metabolic enzyme activities in Great Lakes herring gull embryos.

    PubMed Central

    Lorenzen, A; Moon, T W; Kennedy, S W; Glen, G A

    1999-01-01

    Experiments were conducted to survey and detect differences in plasma corticosterone concentrations and intermediary metabolic enzyme activities in herring gull (Larus argentatus) embryos environmentally exposed to organochlorine contaminants in ovo. Unincubated fertile herring gull eggs were collected from an Atlantic coast control site and various Great Lakes sites in 1997 and artificially incubated in the laboratory. Liver and/or kidney tissues from approximately half of the late-stage embryos were analyzed for the activities of various intermediary metabolic enzymes known to be regulated, at least in part, by corticosteroids. Basal plasma corticosterone concentrations were determined for the remaining embryos. Yolk sacs were collected from each embryo and a subset was analyzed for organochlorine contaminants. Regression analysis of individual yolk sac organochlorine residue concentrations, or 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs), with individual basal plasma corticosterone concentrations indicated statistically significant inverse relationships for polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs), total polychlorinated biphenyls (PCBs), non-ortho PCBs, and TEQs. Similarly, inverse relationships were observed for the activities of two intermediary metabolic enzymes (phosphoenolpyruvate carboxykinase and malic enzyme) when regressed against PCDDs/PCDFs. Overall, these data suggest that current levels of organochlorine contamination may be affecting the hypothalamo-pituitary-adrenal axis and associated intermediary metabolic pathways in environmentally exposed herring gull embryos in the Great Lakes. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:10064546

  7. Effect of the adsorbate (Bromacil) equilibrium concentration in water on its adsorption on powdered activated carbon. Part 1. Equilibrium parameters.

    PubMed

    Al Mardini, Fadi; Legube, Bernard

    2009-10-30

    This study was carried out to investigate the adsorption equilibrium and kinetics of a pesticide of the uracil group on powdered activated carbon (PAC). The experiments were conducted at a wide range of initial pesticide concentrations (approximately 5 microg L(-1) to approximately 500 microg L(-1) at pH 7.8), corresponding to equilibrium concentrations of less than 0.1 microg L(-1) for the weakest, which is compatible with the tolerance limits of drinking water. Such a very broad range of initial solute concentrations resulting powdered activated carbon (PAC) concentrations (0.1-5 mg L(-1)) is the main particularity of our study. The application of several monosolute equilibrium models (two, three or more parameters) has generally shown that Bromacil adsorption is probably effective on two types of sites. High reactivity sites (K(L) approximately 10(3) Lmg(-1)) which are 10-20 less present in a carbon surface than lower reactivity sites (K(L) approximately 10 Lmg(-1)), according to the q(m) values calculated by two- or three-parameter models. The maximum capacity of the studied powdered activated carbon (PAC), corresponding to monolayer adsorption, compared to the Bromacil molecule surface, would be between 170 mg g(-1) and 190 mg g(-1). This theoretical value is very close to the experimental q(m) values obtained when using linearized forms of Langmuir, Tóth and Fritz-Schluender models. PMID:19539425

  8. Regular radon activity concentration and effective dose measurements inside the great pyramid with passive nuclear track detectors.

    PubMed

    Hafez, A F; Bishara, A A; Kotb, M A; Hussein, A S

    2003-08-01

    Radon activity concentrations and equilibrium factors inside the great pyramid of "Cheops" were measured with passive nuclear track detectors. The variation of these concentrations in location was investigated. Seasonal variation of radon activity concentrations with winter maximum and summer minimum were observed inside the pyramid. The 1-y average radon activity concentration ranged from a minimum of 20 to a maximum of 170 Bq m(-3). Results show that the yearly average equilibrium factor between radon and its progeny was assessed as 0.16 and 0.36 inside the pyramid and near entrance, respectively. Moreover, the estimated annual effective dose was 0.05 mSv to tour guides and varied from 0.19 to 0.36 mSv for the pyramid guards; for visitors the average effective dose was 0.15 microSv per visit. These are lower than the 3-10 mSv y(-1) dose limit recommend by ICRP 65. PMID:12938968

  9. Cytotoxic bile acids, but not cytoprotective species, inhibit the ordering effect of cholesterol in model membranes at physiologically active concentrations.

    PubMed

    Mello-Vieira, João; Sousa, Tânia; Coutinho, Ana; Fedorov, Aleksander; Lucas, Susana D; Moreira, Rui; Castro, Rui E; Rodrigues, Cecília M P; Prieto, Manuel; Fernandes, Fábio

    2013-09-01

    Submillimolar concentrations of cytotoxic bile acids (BAs) induce cell death via apoptosis. On the other hand, several cytoprotective BAs were shown to prevent apoptosis in the same concentration range. Still, the mechanisms by which BAs trigger these opposite signaling effects remain unclear. This study was aimed to determine if cytotoxic and cytoprotective BAs, at physiologically active concentrations, are able to modulate the biophysical properties of lipid membranes, potentially translating into changes in the apoptotic threshold of cells. Binding of BAs to membranes was assessed through the variation of fluorescence parameters of suitable derivatized BAs. These derivatives partitioned with higher affinity to liquid disordered than to the cholesterol-enriched liquid ordered domains. Unlabeled BAs were also shown to have a superficial location upon interaction with the lipid membrane. Additionally, the interaction of cytotoxic BAs with membranes resulted in membrane expansion, as concluded from FRET data. Moreover, it was shown that cytotoxic BAs were able to significantly disrupt the ordering of the membrane by cholesterol at physiologically active concentrations of the BA, an effect not associated with cholesterol removal. On the other hand, cytoprotective bile acids had no effect on membrane properties. It was concluded that, given the observed effects on membrane rigidity, the apoptotic activity of cytotoxic BAs could be potentially associated with changes in plasma membrane organization (e.g. modulation of lipid domains) or with an increase in mitochondrial membrane affinity for apoptotic proteins. PMID:23747364

  10. Effects of watershed densities of animal feeding operations on nutrient concentrations and estrogenic activity in agricultural streams.

    PubMed

    Ciparis, Serena; Iwanowicz, Luke R; Voshell, J Reese

    2012-01-01

    Application of manures from animal feeding operations (AFOs) as fertilizer on agricultural land can introduce nutrients and hormones (e.g. estrogens) to streams. A landscape-scale study was conducted in the Shenandoah River watershed (Virginia, USA) in order to assess the relationship between densities of AFOs in watersheds of agricultural streams and in-stream nutrient concentrations and estrogenic activity. The effect of wastewater treatment plants (WWTPs) on nutrients and estrogenic activity was also evaluated. During periods of high and low flow, dissolved inorganic nitrogen (DIN) and orthophosphate (PO(4)-P) concentrations were analyzed and estrogens/estrogenic compounds were extracted and quantified as17β-estradiol equivalents (E2Eq) using a bioluminescent yeast estrogen screen. Estrogenic activity was measurable in the majority of collected samples, and 20% had E2Eq concentrations >1 ng/L. Relatively high concentrations of DIN (>1000 μg/L) were also frequently detected. During all sampling periods, there were strong relationships between watershed densities of AFOs and in-stream concentrations of DIN (R(2) = 0.56-0.81) and E2Eq (R(2) = 0.39-0.75). Relationships between watershed densities of AFOs and PO(4)-P were weaker, but were also significant (R(2) = 0.27-0.57). When combined with the effect of watershed AFO density, streams receiving WWTP effluent had higher concentrations of PO(4)-P than streams without WWTP discharges, and PO(4)-P was the only analyte with a consistent relationship to WWTPs. The results of this study suggest that as the watershed density of AFOs increases, there is a proportional increase in the potential for nonpoint source pollution of agricultural streams and their receiving waters by nutrients, particularly DIN, and compounds that can cause endocrine disruption in aquatic organisms. PMID:22088420

  11. Effects of watershed densities of animal feeding operations on nutrient concentrations and estrogenic activity in agricultural streams

    USGS Publications Warehouse

    Ciparis, S.; Iwanowicz, L.R.; Voshell, J.R.

    2012-01-01

    Application of manures from animal feeding operations (AFOs) as fertilizer on agricultural land can introduce nutrients and hormones (e.g. estrogens) to streams. A landscape-scale study was conducted in the Shenandoah River watershed (Virginia, USA) in order to assess the relationship between densities of AFOs in watersheds of agricultural streams and in-stream nutrient concentrations and estrogenic activity. The effect of wastewater treatment plants (WWTPs) on nutrients and estrogenic activity was also evaluated. During periods of high and low flow, dissolved inorganic nitrogen (DIN) and orthophosphate (PO 4-P) concentrations were analyzed and estrogens/estrogenic compounds were extracted and quantified as17??-estradiol equivalents (E2Eq) using a bioluminescent yeast estrogen screen. Estrogenic activity was measurable in the majority of collected samples, and 20% had E2Eq concentrations >1ng/L. Relatively high concentrations of DIN (>1000??g/L) were also frequently detected. During all sampling periods, there were strong relationships between watershed densities of AFOs and in-stream concentrations of DIN (R 2=0.56-0.81) and E2Eq (R 2=0.39-0.75). Relationships between watershed densities of AFOs and PO 4-P were weaker, but were also significant (R 2=0.27-0.57). When combined with the effect of watershed AFO density, streams receiving WWTP effluent had higher concentrations of PO 4-P than streams without WWTP discharges, and PO 4-P was the only analyte with a consistent relationship to WWTPs. The results of this study suggest that as the watershed density of AFOs increases, there is a proportional increase in the potential for nonpoint source pollution of agricultural streams and their receiving waters by nutrients, particularly DIN, and compounds that can cause endocrine disruption in aquatic organisms. ?? 2011 Elsevier B.V.

  12. Effects of watershed densities of animal feeding operations on nutrient concentrations and estrogenic activity in agricultural streams

    USGS Publications Warehouse

    Ciparis, Serena; Iwanowicz, Luke R.; Voshell, J. Reese

    2012-01-01

    Application of manures from animal feeding operations (AFOs) as fertilizer on agricultural land can introduce nutrients and hormones (e.g. estrogens) to streams. A landscape-scale study was conducted in the Shenandoah River watershed (Virginia, USA) in order to assess the relationship between densities of AFOs in watersheds of agricultural streams and in-stream nutrient concentrations and estrogenic activity. The effect of wastewater treatment plants (WWTPs) on nutrients and estrogenic activity was also evaluated. During periods of high and low flow, dissolved inorganic nitrogen (DIN) and orthophosphate (PO4-P) concentrations were analyzed and estrogens/estrogenic compounds were extracted and quantified as17β-estradiol equivalents (E2Eq) using a bioluminescent yeast estrogen screen. Estrogenic activity was measurable in the majority of collected samples, and 20% had E2Eq concentrations > 1 ng/L. Relatively high concentrations of DIN (> 1000 μg/L) were also frequently detected. During all sampling periods, there were strong relationships between watershed densities of AFOs and in-stream concentrations of DIN (R2 = 0.56–0.81) and E2Eq (R2 = 0.39–0.75). Relationships between watershed densities of AFOs and PO4-P were weaker, but were also significant (R2 = 0.27–0.57). When combined with the effect of watershed AFO density, streams receiving WWTP effluent had higher concentrations of PO4-P than streams without WWTP discharges, and PO4-P was the only analyte with a consistent relationship to WWTPs. The results of this study suggest that as the watershed density of AFOs increases, there is a proportional increase in the potential for nonpoint source pollution of agricultural streams and their receiving waters by nutrients, particularly DIN, and compounds that can cause endocrine disruption in aquatic organisms.

  13. The effect of concentration- and temperature-dependent dielectric constant on the activity coefficient of NaCl electrolyte solutions

    SciTech Connect

    Valiskó, Mónika; Boda, Dezső

    2014-06-21

    Our implicit-solvent model for the estimation of the excess chemical potential (or, equivalently, the activity coefficient) of electrolytes is based on using a dielectric constant that depends on the thermodynamic state, namely, the temperature and concentration of the electrolyte, ε(c, T). As a consequence, the excess chemical potential is split into two terms corresponding to ion-ion (II) and ion-water (IW) interactions. The II term is obtained from computer simulation using the Primitive Model of electrolytes, while the IW term is estimated from the Born treatment. In our previous work [J. Vincze, M. Valiskó, and D. Boda, “The nonmonotonic concentration dependence of the mean activity coefficient of electrolytes is a result of a balance between solvation and ion-ion correlations,” J. Chem. Phys. 133, 154507 (2010)], we showed that the nonmonotonic concentration dependence of the activity coefficient can be reproduced qualitatively with this II+IW model without using any adjustable parameter. The Pauling radii were used in the calculation of the II term, while experimental solvation free energies were used in the calculation of the IW term. In this work, we analyze the effect of the parameters (dielectric constant, ionic radii, solvation free energy) on the concentration and temperature dependence of the mean activity coefficient of NaCl. We conclude that the II+IW model can explain the experimental behavior using a concentration-dependent dielectric constant and that we do not need the artificial concept of “solvated ionic radius” assumed by earlier studies.

  14. Platelet and growth factor concentrations in activated platelet-rich plasma: a comparison of seven commercial separation systems.

    PubMed

    Kushida, Satoshi; Kakudo, Natsuko; Morimoto, Naoki; Hara, Tomoya; Ogawa, Takeshi; Mitsui, Toshihito; Kusumoto, Kenji

    2014-06-01

    Platelet-rich plasma (PRP) is blood plasma that has been enriched with platelets. It holds promise for clinical use in areas such as wound healing and regenerative medicine, including bone regeneration. This study characterized the composition of PRP produced by seven commercially available separation systems (JP200, GLO PRP, Magellan Autologous Platelet Separator System, KYOCERA Medical PRP Kit, SELPHYL, MyCells, and Dr. Shin's System THROMBO KIT) to evaluate the platelet, white blood cell, red blood cell, and growth factor concentrations, as well as platelet-derived growth factor-AB (PDGF-AB), transforming growth factor beta-1 (TGF-β1), and vascular endothelial growth factor (VEGF) concentrations. PRP prepared using the Magellan Autologous Platelet Separator System and the KYOCERA Medical PRP Kit contained the highest platelet concentrations. The mean PDGF-AB concentration of activated PRP was the highest from JP200, followed by the KYOCERA Medical PRP Kit, Magellan Autologous Platelet Separator System, MyCells, and GLO PRP. TGF-β1 and VEGF concentrations varied greatly among individual samples, and there was almost no significant difference among the different systems, unlike for PDGF. The SELPHYL system produced PRP with low concentrations of both platelets and growth factors. Commercial PRP separation systems vary widely, and familiarity with their individual advantages is important to extend their clinical application to a wide variety of conditions. PMID:24748436

  15. Adsorption of pharmaceuticals onto activated carbon fiber cloths - Modeling and extrapolation of adsorption isotherms at very low concentrations.

    PubMed

    Fallou, Hélène; Cimetière, Nicolas; Giraudet, Sylvain; Wolbert, Dominique; Le Cloirec, Pierre

    2016-01-15

    Activated carbon fiber cloths (ACFC) have shown promising results when applied to water treatment, especially for removing organic micropollutants such as pharmaceutical compounds. Nevertheless, further investigations are required, especially considering trace concentrations, which are found in current water treatment. Until now, most studies have been carried out at relatively high concentrations (mg L(-1)), since the experimental and analytical methodologies are more difficult and more expensive when dealing with lower concentrations (ng L(-1)). Therefore, the objective of this study was to validate an extrapolation procedure from high to low concentrations, for four compounds (Carbamazepine, Diclofenac, Caffeine and Acetaminophen). For this purpose, the reliability of the usual adsorption isotherm models, when extrapolated from high (mg L(-1)) to low concentrations (ng L(-1)), was assessed as well as the influence of numerous error functions. Some isotherm models (Freundlich, Toth) and error functions (RSS, ARE) show weaknesses to be used as an adsorption isotherms at low concentrations. However, from these results, the pairing of the Langmuir-Freundlich isotherm model with Marquardt's percent standard of deviation was evidenced as the best combination model, enabling the extrapolation of adsorption capacities by orders of magnitude. PMID:26606322

  16. Effect of zinc concentration on the activity of angiotensin converting enzyme in human plasma and serum

    SciTech Connect

    Reeves, P.G.; Carl, G.F.; Smith, D.K.; O'Dell, B.L.

    1986-03-05

    The activity of angiotensin converting enzyme is measured clinically to assist in the diagnosis of sarcoidosis and to monitor therapy with steroids, and with antihypertensive drugs that inhibit the enzyme. Even though it has been known for some time that ACE is a zinc dependent enzyme, it was discovered only recently that zinc, in addition to endogenous levels in the assay mixture, is required for maximal activity of rat serum ACE. The present experiment was designed to determine if additional zinc is required for maximal activation of ACE in plasma and serum of human subjects. Plasma or serum samples were incubated at 37/sup 0/ in a zinc-free medium, pH 7.4, containing hippurylglyclglycine as the substrate. The addition of 20 ..mu..M zinc significantly increased ACE activity in plasma (95.4 +/- 11.9 vs 192.8 +/- 24.3 U/L) and in serum (89.9 +/- 5.6 vs 195.7 +/- 9.3 U/L) compared to samples without added zinc. Enzyme activity was increased 2.4-fold when zinc was added to plasma from a patient with low plasma zinc. These data suggest that the endogenous level of zinc in the assay mixture resulting from the addition of an aliquot of plasma or serum is insufficient to obtain maximal activity of ACE. The addition of zinc to zinc deficient plasma increased ACE activity even more.

  17. In Vitro Activity and Fecal Concentration of Rifaximin after Oral Administration

    PubMed Central

    Jiang, Zhi-Dong; Ke, Shi; Palazzini, Ernesto; Riopel, Lise; Dupont, Herbert

    2000-01-01

    Rifaximin showed moderately high MICs (the MIC at which 90% of the isolates tested were inhibited = 50 μg/ml) for 145 bacterial enteropathogens from patients with traveler's diarrhea acquired in Mexico during the summers of 1997 and 1998. Rifaximin concentrations in stool the day after oral administration (800 mg daily for 3 days) were high (average, 7,961 μg/g), proving the value of the drug. PMID:10898704

  18. Neutron activation analysis of some building materials

    NASA Astrophysics Data System (ADS)

    Salagean, M. N.; Pantelica, A. I.; Georgescu, I. I.; Muntean, M. I.

    1999-01-01

    Concentrations of As, Au, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Mo, Na, Nd, Rb, Sb, Sc, Sr, Ta, Tb, Th, U. Yb, W and Zn in seven Romanian building materials were determined by the Instrumental Neutron Activation Analysis (INAA) method using the VVR-S Reactor of NIPNE- Bucharest. Raw matarials used in cement obtaining ≈ 75% of limestone and ≈ 25% of clay, cement samples from three different factories, furnace slag, phosphogypsum, and a type of brick have been analyzed. The brick was compacted from furnace slay, fly coal ash, phosphogypsum, lime and cement. The U, Th and K concentrations determined in the brick are in agreement with the natural radioactivity measurements of226Ra,232Th and40K. These specific activities were found about twice and 1.5 higher than the accepted levels in the case of226Ra and232Th, as well as40K, respectively. By consequence, the investigated brick is considered a radioactive waste. The rather high content of Co, Cr, K, Th, and Zh in the brick is especially due to the slag and fly ash, the main componets. The presence of U, Th and K in slag is mainly correlated with the limestone and dolomite as fluxes in matallurgy.

  19. Biokinetic models for representing the complete inhibition of microbial activity at high substrate concentrations.

    PubMed

    Alagappan, G; Cowan, R M

    2001-11-20

    This paper reintroduces the Wayman and Tseng model for representing substrate inhibition effects on specific growth rate by further documenting its potential predictive capabilities. It also introduces a modification to this model in which an Andrews inhibition function is used in place of the Monod noninhibitory substrate function. This modification better represents the relationship between specific growth rate and substrate concentration for those substrates that show Andrews type inhibition at lower substrate concentrations, rather than the Monod type noninhibitory behavior described in the model of Wayman and Tseng. Results from nonlinear, least squares regression analysis are used to evaluate the ability of these models to empirically represent experimental data (both new and from the literature). The statistical goodness of fit is evaluated by comparing the regression results against those obtained using other empirical models. Finally, possible mechanisms of toxicity responsible for the observed inhibition trends are used to further justify use of these empirical models. The dominant mechanism considered to be relevant for conceptually explaining complete inhibition at high concentrations of solvents is the deterioration of cell membrane integrity. Literature citations are used to support this argument. This work should lead to improvements in the mathematical modeling of contaminant fate and transport in the environment and in the simulation of microbial growth and organic compound biodegradation in engineered systems. PMID:11668439

  20. IMPROVED PLANAR KIDNEY ACTIVITY CONCENTRATION ESTIMATE BY THE POSTERIOR VIEW METHOD IN 177LU-DOTATATE TREATMENTS.

    PubMed

    Magnander, Tobias; Svensson, Johanna; Båth, Magnus; Gjertsson, Peter; Bernhardt, Peter

    2016-06-01

    The aims of this study were to determine how different background regions of interest (ROIs) around the kidney represent true background activity in over- and underlying tissues in (177)Lu-DOTA-octreatate ((177)Lu-DOTATATE) treatments and to determine the influence of the background positions on the kidney activity concentration estimates by the conjugate view (ConjV) and posterior view (PostV) methods. The analysis was performed in single-photon emission computed tomography (SPECT) images of 20 patients, acquired 24 h post injection of a (177)Lu-DOTATATE treatment, by a computer algorithm that created planar images from the SPECT data. The ratio between the activity concentration in the background and the true background varied from 0.36 to 2.08 [coefficient of variation (CV) = 25-181 %] and from 0.44 to 1.52 (CV = 16-70 %) for the right and left kidneys, respectively. The activity concentration estimate in the kidneys was most accurate with the PostV method using a background ROI surrounding the whole kidney, and this combination might be an alternative planar method for improved kidney dosimetry in the (177)Lu-DOTATATE treatments. PMID:27012883

  1. IMPROVED PLANAR KIDNEY ACTIVITY CONCENTRATION ESTIMATE BY THE POSTERIOR VIEW METHOD IN 177LU-DOTATATE TREATMENTS

    PubMed Central

    Magnander, Tobias; Svensson, Johanna; Båth, Magnus; Gjertsson, Peter; Bernhardt, Peter

    2016-01-01

    The aims of this study were to determine how different background regions of interest (ROIs) around the kidney represent true background activity in over- and underlying tissues in 177Lu-DOTA-octreatate (177Lu-DOTATATE) treatments and to determine the influence of the background positions on the kidney activity concentration estimates by the conjugate view (ConjV) and posterior view (PostV) methods. The analysis was performed in single-photon emission computed tomography (SPECT) images of 20 patients, acquired 24 h post injection of a 177Lu-DOTATATE treatment, by a computer algorithm that created planar images from the SPECT data. The ratio between the activity concentration in the background and the true background varied from 0.36 to 2.08 [coefficient of variation (CV) = 25–181 %] and from 0.44 to 1.52 (CV = 16–70 %) for the right and left kidneys, respectively. The activity concentration estimate in the kidneys was most accurate with the PostV method using a background ROI surrounding the whole kidney, and this combination might be an alternative planar method for improved kidney dosimetry in the 177Lu-DOTATATE treatments. PMID:27012883

  2. Selenium status, lipid peroxides concentration, and glutathione peroxidase activity in the blood of power station and rubber factory workers

    SciTech Connect

    Zachara, B.A.; Wasowicz, W.; Sklodowska, M.; Gromadzinska, J.

    1987-07-01

    Concentration of selenium in whole blood and plasma, lipid peroxides in plasma, and glutathione peroxidase activities in red blood cell hemolysates and plasma were determined in 49 coal power plant workers and in 50 rubber factory workers. The results were compared with those obtained for 58 nonindustrial controls. Whole blood selenium was significantly lower and plasma lipid peroxides were significantly higher in power plant workers when compared to the nonindustrial group. In the rubber factory workers, whole blood selenium and red blood cells and plasma glutathione peroxidase activities were significantly lower than in the control group. Urinary output of selenium was also significantly decreased in rubber factory workers. Slightly elevated lipid peroxides were also observed in that group. It seems reasonable to conclude that the lower blood selenium and decreased urinary output of this element may result from increased loss of selenium with perspiration. No correlation has been observed between selenium concentration and glutathione peroxidase activity and between enzyme activity and lipid peroxides concentration in the industrial group.

  3. BLOOD AND BRAIN CONCENTRATIONS OF BIFENTHRIN CORRELATE WITH DECREASED MOTOR ACTIVITY INDEPENDENT OF TIME OF EXPOSURE

    EPA Science Inventory

    Pyrethroids are neurotoxic insecticides used in a variety of agricultural and household activities. Due to the phase-out of organophosphate pesticides, the use of pyrethroids has increased. The potential for human exposure to pyrethroids has prompted pharmacodynamic and pharmac...

  4. Activation and deactivation of high concentration arsenic with some evidence of precipitation

    SciTech Connect

    Rousseau, P.M.; Griffin, P.B.; Plummer, J.D.; Carey, P.G.

    1992-12-29

    Using box-shaped profiles created by laser melt annealing, the authors investigate the kinetics of arsenic activation and deactivation. They find deactivation shows no history effects, which can be consistent either with clustering or precipitation for the cases considered. For activation, they notice it occurs on very short time scales, followed by a slower deactivation process. This is suggestive evidence that at least some precipitation occurs.

  5. Natural fermentation of lentils. Influence of time, concentration and temperature on protein content, trypsin inhibitor activity and phenolic compound content.

    PubMed

    Tabera, J; Frias, J; Estrella, I; Villa, R; Vidal-Valverde, C

    1995-12-01

    Lentil (Lens culinaris var. vulgaris) flour was naturally fermented for 4 days at different temperatures (28 degrees C, 35 degrees C and 42 degrees C) and concentrations (79 milligrams, 150 milligrams and 221 milligrams). Samples were analysed to establish the changes of total protein content and in vitro protein digestibility, trypsin inhibitor activity (TIA) and phenolic compound content during natural fermentation of lentils. The preparation of lentil flour suspensions to be fermented caused a slight increase in total protein and in vitro protein digestibility content, a decrease of TIA and a sharp decrease the tannin/catechin ratio. During the whole fermentation procedure, the minimum initial lentil concentration and temperature used (79 milligrams, 28 degrees C) achieved the maximum protein content and the lowest tannin/catechin ratio. The TIA was more affected by temperature than by concentration, and a 62.5% reduction was observed at 42 degrees C and 79 milligrams. PMID:8585337

  6. Bacterial maximum non-inhibitory and minimum inhibitory concentrations of different water activity depressing solutes.

    PubMed

    Cebrián, G; Arroyo, C; Mañas, P; Condón, S

    2014-10-01

    The NaCl MNICs (maximum non-inhibitory concentrations) and MICs (minimum inhibitory concentrations) for growth of various strains of six bacterial species were determined and then compared with those obtained for seven other solutes. The influence of prior growth conditions on the MNICs and MICs was also evaluated. No significant changes on the MNICs and MICs were found among the strains studied within each species. Among all factors investigated, only growth phase -for Gram-negatives- and growth at high NaCl concentrations led to a change in the NaCl MNICs. Species could be classified depending on its NaCl MNICs and MICs (in decreasing order) as follows: Staphylococcus aureus, Listeria monocytogenes, Cronobacter sakazakii, Enterococcus faecium, Escherichia coli and Salmonella Typhimurium. Similar results were obtained for KCl, LiCl, and sodium acetate, but not for the remaining solutes investigated (sucrose, glycerol, MgCl2 and CaCl2). Results obtained indicate that, in general, Gram-negatives showed lower MNICs and MICs than Gram-positives for all the solutes, S. aureus being the most solute tolerant microorganism. When compared on a molar basis, glycerol showed the highest MNICs and MICs for all the microorganisms -except for S. aureus- and LiCl the lowest ones. NaCl MNICs and MICs were not significantly different from those of KCl when compared on a molar basis. Therefore, the inhibitory action of NaCl could not be linked to the specific action of Na(+). Results also showed that the Na(+) tolerance of some species was Cl(-) dependent whereas for others it was not, and that factors others than aw-decrease contribute to the inhibitory action of LiCl, CaCl2 and MgCl2. PMID:25090605

  7. Strong nonlinear focusing of light in nonlinearly controlled electromagnetic active metamaterial field concentrators

    NASA Astrophysics Data System (ADS)

    Rapoport, Yu G.; Boardman, A. D.; Grimalsky, V. V.; Ivchenko, V. M.; Kalinich, N.

    2014-05-01

    The idea of nonlinear ‘transformation optics-inspired’ [1-6] electromagnetic cylindrical field concentrators has been taken up in a preliminary manner in a number of conference reports [7-9]. Such a concentrator includes both external linear region with a dielectric constant increased towards the centre and internal region with nonlinearity characterized by constant coefficients. Then, in the process of farther investigations we realized the following factors considered neither in [7-9] nor in the recent paper [10]: saturation of nonlinearity, nonlinear losses, linear gain, numerical convergence, when nonlinear effect becomes very strong and formation of ‘hotspots’ starts. It is clearly demonstrated here that such a strongly nonlinear process starts when the nonlinear amplitude of any incident beam(s) exceeds some ‘threshold’ value. Moreover, it is shown that the formation of hotspots may start as the result of any of the following processes: an increase of the input amplitude, increasing the linear amplification in the central nonlinear region, decreasing the nonlinear losses, a decrease in the saturation of the nonlinearity. Therefore, a tendency to a formation of ‘hotspots’ is a rather universal feature of the strongly nonlinear behaviour of the ‘nonlinear resonator’ system, while at the same time the system is not sensitive to the ‘prehistory’ of approaching nonlinear threshold intensity (amplitude). The new proposed method includes a full-wave nonlinear solution analysis (in the nonlinear region), a new form of complex geometric optics (in the linear inhomogeneous external cylinder), and new boundary conditions, matching both solutions. The observed nonlinear phenomena will have a positive impact upon socially and environmentally important devices of the future. Although a graded-index concentrator is used here, it is a direct outcome of transformation optics. Numerical evaluations show that for known materials these nonlinear effects

  8. Studies on Thorium Adsorption Characteristics upon Activated Titanium Hydroxide Prepared from Rosetta Ilmenite Concentrate

    SciTech Connect

    Gado, M Zaki, S

    2016-01-01

    The titanium hydroxide prepared from Rosetta ilmenite concentrate has been applied for Th (IV) adsorption from its acid aqueous solutions. The prepared hydroxide is first characterized by both Fourier transform infrared (FT-IR) spectrum and thermogravimetric analysis. The relevant factors affecting the adsorption process have been studied. The obtained equilibrium data fits well with the Langmuir isotherm rather than Freundlich isotherm, while the adsorption kinetic data follow the pseudo-second order model. The different thermodynamic parameters have also been calculated and indicate that the adsorption process is spontaneous.

  9. Understanding the effect of magnesium ion concentration on the catalytic activity of ribonuclease H through computation: Does a third metal binding site modulate endonuclease activity?

    PubMed Central

    Ho, Ming-Hsun; De Vivo, Marco; Peraro, Matteo Dal; Klein, Michael L.

    2010-01-01

    Ribonuclease H (RNase H) belongs to the nucleotidyl-transferase (NT) superfamily and hydrolyzes the phosphodiester linkage on the RNA strand of a DNA/RNA hybrid duplex. Due to its activity in HIV reverse transcription, it represents a promising target for anti-HIV drug design. While crystallographic data have located two ions in the catalytic site, there is ongoing debate concerning just how many metal ions bound at the active site are optimal for catalysis. Indeed, experiments have shown a dependency of the catalytic activity on the Mg2+ concentration. Moreover, in RNase H the glutamate residue E188 has been shown to be essential for full enzymatic activation regardless of the Mg2+ concentration. The catalytic center is known to contain two Mg2+ ions (Nowotny et al.) and E188 is not one of the primary metal ligands. Herein, classical molecular dynamics (MD) simulations are employed to study the metal-ligand coordination in RNase H at different concentration of Mg2+. Importantly, the presence of a third Mg2+ ion, bound to the second-shell ligand E188, is persistent feature of the MD simulations. Free energy calculations have identified two distinct conformations depending on the concentration of Mg2+. At standard concentration, a third Mg2+ is found in the catalytic pocket but it does not perturb the optimal RNase H active conformation. However, at higher concentration, the third Mg2+ ion heavily perturbs the nucleophilic water and thereby influences the catalytic efficiency of RNase H. In addition, the E188A mutant shows no ability to engage additional Mg2+ ions nearby the catalytic pocket. This finding likely explains the decrease in catalytic activity of E188A, and also supports the key role of E188 in localizing the third Mg2+ ion at the active site. Glutamate residues are commonly found surrounding the metal center in the endonuclease family, which suggests that this structural motif may be an important feature to enhance catalytic activity. The present MD

  10. Vitamin D concentrations and disease activity in Moroccan children with juvenile idiopathic arthritis

    PubMed Central

    2014-01-01

    Background In addition to its important metabolic activities, vitamin D also contributes to the regulation of the immune system. The aim of this study was to assess the relationship between hypovitaminosis D and disease activity in Moroccan children with juvenile idiopathic arthritis (JIA). Methods In this cross-sectional study, forty children with JIA were included, all having been diagnosed according to the classification criteria of International League of Associations for Rheumatology (ILAR). The children underwent anthropometric assessment and clinical evaluation. Disease activity was measured using the Disease Activity Score in 28 joints (DAS28) for polyarticular and oligoarticular JIA and the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) for enthesitis-related arthritis. Serum 25-hydroxyvitamin [25(OH)D] D2 and D3 were measured using radioimmunoassay (RIA). Hypovitaminosis D was defined as serum 25(OH)D <30 ng/ml. Results The average age of participants was 11 years ± 4.23. Hypovitaminosis D was observed in 75% of patients. In univariate analyses, 25(OH)D levels were negatively associated with DAS28 for polyarticular and oligoarticular JIA. No significant relationship was found between 25(OH)D levels and BASDAI for juvenile spondylarthropathy. In multivariate linear regression analysis, no association persisted between 25(OH)D levels and DAS28. Conclusions Our study suggested that serum levels of vitamin D were low in Moroccan children with JIA disease. Future studies with a larger population are needed to confirm our results. PMID:24690195

  11. Exposure to Environmentally Relevant Concentrations of Genistein during Activation Does Not Affect Sperm Motility in the Fighting Fish Betta splendens

    PubMed Central

    Clotfelter, Ethan D.; Gendelman, Hannah K.

    2014-01-01

    Sperm collected from male fighting fish Betta splendens were activated in control water, water containing the ion-channel blocker gadolinium (a putative positive control), or water containing the isoflavone phytoestrogen genistein to determine the effects of acute genistein exposure on male reproductive function. Computer-assisted sperm analysis was used to quantify the proportion of sperm that were motile and the swimming velocity of those sperm. The highest concentration of gadolinium (100 μM) tested was effective at reducing sperm motility and velocity, but neither concentration of genistein tested (3.7 nM or 3.7 μM) significantly affected these sperm parameters. Our findings suggest that acute exposure to waterborne phytoestrogens during activation does not reduce the motility of fish sperm. PMID:24516856

  12. Exposure to environmentally relevant concentrations of genistein during activation does not affect sperm motility in the fighting fish Betta splendens.

    PubMed

    Clotfelter, Ethan D; Gendelman, Hannah K

    2014-01-01

    Sperm collected from male fighting fish Betta splendens were activated in control water, water containing the ion-channel blocker gadolinium (a putative positive control), or water containing the isoflavone phytoestrogen genistein to determine the effects of acute genistein exposure on male reproductive function. Computer-assisted sperm analysis was used to quantify the proportion of sperm that were motile and the swimming velocity of those sperm. The highest concentration of gadolinium (100 μ M) tested was effective at reducing sperm motility and velocity, but neither concentration of genistein tested (3.7 nM or 3.7 μ M) significantly affected these sperm parameters. Our findings suggest that acute exposure to waterborne phytoestrogens during activation does not reduce the motility of fish sperm. PMID:24516856

  13. Metal Ion Concentrations in Young, Active Patients Following Total Hip Arthroplasty with the Use of Modern Bearing Couples.

    PubMed

    Nam, Denis; Keeney, James A; Nunley, Ryan M; Johnson, Staci R; Clohisy, John C; Barrack, Robert L

    2015-12-01

    The purpose of this study was to compare whole blood metal ion levels in young, active patients undergoing primary total hip arthroplasty with the use of a cobalt-alloy (ten patients), ceramic (15 patients), or oxinium (11 patients) femoral head and highly crosslinked polyethylene acetabular liner. At 2 years postoperatively, mean cobalt concentrations were 3.0 times higher in the cobalt-alloy cohort versus the ceramic cohort, and 2.3 times higher versus the oxinium cohort (P=0.3-0.5). Titanium levels were consistently elevated at all postoperative time points versus preoperatively in all cohorts. Young, active patients following THA demonstrate elevated cobalt and titanium concentrations. Use of a ceramic or oxinium femoral head decreased the degree of cobalt elevation versus a cobalt-alloy femoral head, but did not reach statistical significance. PMID:26164561

  14. Effects of lead shot ingestion on delta-aminolevulinic acid dehydratase activity, hemoglobin concentration, and serum chemistry in bald eagles

    USGS Publications Warehouse

    Hoffman, D.J.; Pattee, O.H.; Wiemeyer, Stanley N.; Mulhern, B.

    1981-01-01

    Lead shot ingestion by bald eagles (Haliaeetus leucocephalus) is considered to be widespread and has been implicated in the death of eagles in nature. It was recently demonstrated under experimental conditions that ingestion of as few as 10 lead shot resulted in death within 12 to 20 days. In the present study hematological responses to lead toxicity including red blood cell ALAD activity, hemoglobin concentration and 23 different blood serum chemistries were examined in five captive bald eagles that were unsuitable for rehabilitation and release. Eagles were dosed by force-feeding with 10 lead shot; they were redosed if regurgitation occurred. Red blood cell ALAD activity was inhibited by nearly 80% within 24 hours when mean blood lead concentration had increased to 0.8 parts per million (ppm). By the end of 1 week there was a significant decrease (20-25%) in hematocrit and hemoglobin, and the mean blood lead concentration was over 3 ppm. Within as little as 1-2 weeks after dosing, significant elevations in serum creatinine and serum alanine aminotransferase occurred, as well as a significant decrease in the ratio of serum aspartic aminotransferase to serum alanine aminotransferase. The mean blood lead concentration was over 5 ppm by the end of 2 weeks. These changes in serum chemistry may be indicative of kidney and liver alterations.

  15. Environmental impact assessment of the mining and concentration activities in the Kola Peninsula, Russia by multidate remote sensing.

    PubMed

    Rigina, Olga

    2002-04-01

    On the Kola Peninsula, the mining and concentration industry exerts anthropogenic impact on the environment. Tailing dumps cause airborne pollution through dusting, and waterborne pollution due to direct dumping and accidental releases. The objectives were: (1) to analyse multidate satellite images for 1964-1996 to assess the environmental pollution from the mining and concentration activity in the Kola in temporal perspective; (2) to evaluate remote sensing methods for integrated environmental impact assessment. The area of mining and industrial sites steadily expands and amounted to 94 km2 in 1996. The polluted water surface amounted to at least 150 km2 through dumping in 1978 and to 106 km2 in 1986 due to dusting. Thus, the impact from the mining and concentration activity should be reconsidered as more significant than it was officially anticipated. In the past the main mechanism of pollution was direct dumping into the lakes. Currently and in future, airborne pollution after dusting storms will dominate. The effective recultivation of the tailing dumps will be a long-term process. For effective assessment of impacts from the mining and concentration industry, remote sensing methods should be complemented by in-situ measurements, fieldwork, and mathematical modelling. PMID:15900663

  16. Comparison of the expression, activity, and fecal concentration of intestinal alkaline phosphatase between healthy dogs and dogs with chronic enteropathy.

    PubMed

    Ide, Kaori; Kato, Kazuki; Sawa, Yuki; Hayashi, Akiko; Takizawa, Rei; Nishifuji, Koji

    2016-07-01

    OBJECTIVE To compare expression, activity, and fecal concentration of intestinal alkaline phosphatase (IAP) between healthy dogs and dogs with chronic enteropathy (CE). ANIMALS 9 healthy university-owned Beagles and 109 healthy client-owned dogs (controls) and 28 dogs with CE (cases). PROCEDURES Cases were defined as dogs with persistent (> 3 weeks) gastrointestinal signs that failed to respond to antimicrobials and anti-inflammatory doses of prednisolone or dietary trials, did not have mechanical gastrointestinal abnormalities as determined by abdominal radiography and ultrasonography, and had a diagnosis of lymphoplasmacytic enteritis or eosinophilic gastroenteritis on histologic examination of biopsy specimens. Duodenal and colonic mucosa biopsy specimens were obtained from the 9 university-owned Beagles and all cases for histologic examination and determination of IAP expression (by real-time quantitative PCR assay) and activity (by enzyme histochemical analysis). Fecal samples were obtained from all dogs for determination of fecal IAP concentration by a quantitative enzyme reaction assay. RESULTS For dogs evaluated, IAP expression and activity were localized at the luminal side of epithelial cells in the mucosa and intestinal crypts, although both were greater in the duodenum than in the colon. Active IAP was detected in the feces of all dogs. Intestinal alkaline phosphatase expression and activity were lower for cases than for controls, and fecal IAP concentration for dogs with moderate and severe CE was lower than that for dogs with mild CE. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that dogs with CE had impaired IAP expression and activity. Additional research is necessary to elucidate the role of IAP in the pathogenesis of CE. PMID:27347825

  17. Application of PAH concentration profiles in lake sediments as indicators for smelting activity.

    PubMed

    Warner, Wiebke; Ruppert, Hans; Licha, Tobias

    2016-09-01

    The ability of lake sediment cores to store long-term anthropogenic pollution establishes them as natural archives. In this study, we focus on the influence of copper shale mining and smelting in the Mansfeld area of Germany, using the depth profiles of two sediment cores from Lake Süßer See. The sediment cores provide a detailed chronological deposition history of polycyclic aromatic hydrocarbons (PAHs) and heavy metals in the studied area. Theisen sludge, a fine-grained residue from copper shale smelting, reaches the lake via deflation by wind or through riverine input; it is assumed to be the main source of pollution. To achieve the comparability of absolute contaminant concentrations, we calculated the influx of contaminants based on the sedimentation rate. Compared to the natural background concentrations, PAHs are significantly more enriched than heavy metals. They are therefore more sensitive and selective for source apportionment. We suggest two diagnostic ratios of PAHs to distinguish between Theisen sludge and its leachate: the ratio fluoranthene to pyrene ~2 and the ratio of PAH with logKOW<5.7 to PAH with a logKOW>5.7 converging to an even lower value than 2.3 (the characteristic of Theisen sludge) to identify the particulate input in lake environments. PMID:27176930

  18. Use of protein-acrylamide copolymer hydrogels for measuring protein concentration and activity.

    PubMed

    Brueggemeier, Shawn B; Kron, Stephen J; Palecek, Sean P

    2004-06-15

    We report the development and characterization of a polyacrylamide-based protein immobilization strategy for surface-bound protein assays, including concentration detection, binding affinity, and enzyme kinetics. Glutathione S-transferase (GST) fusion proteins have been labeled with an acrylic moiety and attached to acrylic-functionalized glass surfaces through copolymerization with acrylic monomer. The specific attachment of GST-green fluorescent protein (GFP) fusion protein was more than sevenfold greater than the nonspecific attachment of nonacrylic-labeled GST-GFP; 0.32 ng/mm(2) of surface-attached GST-GFP was detectable by direct measurement of GFP fluorescence and this lower detection limit was reduced to 0.080 ng/mm(2) using indirect antibody-based detection. The polyacrylamide-based surface attachment strategy was also used to measure the kinetics of substrate phosphorylation by the kinase c-Src. Michaelis-Menten kinetic constants for the reaction occurring in solution were K(m) = 2.7 +/- 1.0 microM and V(max) = 8.1 +/- 3.1 (arbitrary units). Kinetic values for the reaction utilizing surface-immobilized substrate were K(m) = 0.36 +/- 0.033 microM and V(max) = 9.7 +/- 0.63 and were found to be independent of the acrylamide concentration within the copolymer. Such a surface attachment strategy should be applicable to the proteomics field and addresses denaturation and dehydration problems associated with protein microarray development. PMID:15158476

  19. Active concentration of vorticity along the leading edge of a semi-circular wing

    NASA Astrophysics Data System (ADS)

    Williams, David; Collins, Jesse; Colonius, Tim

    2007-11-01

    Leading-edge vorticity concentration plays a key role in lift enhancement for insect flight, swept wings on aircraft, and in unsteady flows through the formation of the dynamic stall vortex. Using 16 spatially localized pulsed-blowing actuators, we are able to concentrate the vorticity at the leading edge of a wing with a semi-circular planform. The experiments are done in a wind tunnel with a model chord Reynolds number of 68,000. Peak vorticity values double those of the unforced case result in an 80 percent increase in lift on the wing relative to the unforced post-stall lift. The semi-circular wing obtains lift coefficients approximately 35 percent larger than a rectangular planform wing with a comparable aspect ratio. The sweep of the wing's leading edge is believed to establish a spanwise transport of vorticity, contributing to the stabilization of the leading edge vortex. Closed-loop control of the wing plunging motion in an unsteady flow stream is demonstrated by modulating the strength of the leading-edge vorticity via a proportional-derivative controller.

  20. Simultaneous sub-Doppler laser cooling of fermionic 6Li and 40K on the D1 line: Theory and experiment

    NASA Astrophysics Data System (ADS)

    Sievers, Franz; Kretzschmar, Norman; Fernandes, Diogo Rio; Suchet, Daniel; Rabinovic, Michael; Wu, Saijun; Parker, Colin V.; Khaykovich, Lev; Salomon, Christophe; Chevy, Frédéric

    2015-02-01

    We report on simultaneous sub-Doppler laser cooling of fermionic 6Li and 40K using the D1 optical transitions. We compare experimental results to a numerical simulation of the cooling process applying a semiclassical Monte Carlo wave-function method. The simulation takes into account the three-dimensional optical molasses setup and the dipole interaction between atoms and the bichromatic light field driving the D1 transitions. We discuss the physical mechanisms at play, identify the important role of coherences between the ground-state hyperfine levels, and compare D1 and D2 sub-Doppler cooling. In 5 ms, the D1 molasses phase greatly reduces the temperature for both 6Li and 40K at the same time, with final temperatures of 44 and 11 μ K , respectively. For both species this leads to a phase-space density close to 10-4. These conditions are well suited to direct loading of an optical or magnetic trap for efficient evaporative cooling to quantum degeneracy.

  1. The optimization process of biodiesel production using multiple feedstock (CPO and Jatropha) with assistance of ultrasound at 40 kHz

    NASA Astrophysics Data System (ADS)

    Fajar, Berkah; Wilis, Widayat

    2016-06-01

    CPO prices are unstable, therefore affecting the supply of feedstock to produce biodiesel [2]. To overcome the shortage of feedstock, it is necessary to use multiple feedstock, in this case is CPO and Jatropha [1]. This objective of this work to optimizate biodiesel production using multifeedstock (CPO and Jatropha) with assistance of ultrasound. The optimization was to find the highest yield and the least production time. Experiments was carried out using an ultrasonic bath at a frequency of 40 kHz. The ratio of CPO and Jatropha was 1: 1, 3: 1, 4: 1 while the ratio of methanol and oil was 5: 1, 6: 1, 7: 1 and the reaction time was 50, 60, and 70 minutes. KOH was used as a catalyst. The experiment data was optimized using a Response Surface Methodology [3,4]. The optimum point was at a frequency of 40 kHz obtained at a 2.8: 1 mixture of CPO - Jatropha, 6.4: 1 molar ratio of methanol-oil and 61.5 minutes of reaction time. The results of quality testing shows that the biodiesel produced meets the ASTM standard D6751 and SNI 04-7182-2006[5].

  2. A review of conditions affecting the radiolysis due to 40K on nucleic acid bases and their derivatives adsorbed on clay minerals: implications in prebiotic chemistry.

    PubMed

    Mosqueira, F G; Albarran, G; Negron-Mendoza, A

    1996-02-01

    This paper describes the possible effects of ionizing radiation arising from long-lived soluble radionuclides within clays, in particular 40K, at the epoch of the emergence of life on Earth. The free dispersion of soluble radionuclides constitutes an effective in situ irradiation mechanism that might have acted upon adsorbed nucleic bases and their derivatives on clays, inducing chemical changes on these organic molecules. Several types of well documented reactions for radiolysis of nucleic acid bases and their derivatives are known, even at low doses (i.e., 0.1 Gy). For example, estimates with a dose rate calculated from 40K from deep sea clays at 3.8 Ga ago, indicates that over a period of 1000 years the amount of organic material transformated is 1.8 X 10(-7) moles/kg-clay. Although ionizing radiation may also induce synthetic reactions with prebiological interest, all in all these considerations indicate that nucleic acid bases and their derivatives adsorbed on clays were exposed for long periods to degradation conditions. Such situation promotes decomposition of organic molecules rather than protection of them and enhancement of farther polymerization, as it has been usually taken for granted. PMID:11536747

  3. Growth and activity of ANME clades with different sulfate and sulfide concentrations in the presence of methane

    PubMed Central

    Timmers, Peer H. A.; Widjaja-Greefkes, H. C. A.; Ramiro-Garcia, Javier; Plugge, Caroline M.; Stams, Alfons J. M.

    2015-01-01

    Extensive geochemical data showed that significant methane oxidation activity exists in marine sediments. The organisms responsible for this activity are anaerobic methane-oxidizing archaea (ANME) that occur in consortia with sulfate-reducing bacteria. A distinct zonation of different clades of ANME (ANME-1, ANME-2a/b, and ANME-2c) exists in marine sediments, which could be related to the localized concentrations of methane, sulfate, and sulfide. In order to test this hypothesis we performed long-term incubation of marine sediments under defined conditions with methane as a headspace gas: low or high sulfate (±4 and ±21 mM, respectively) in combination with low or high sulfide (±0.1 and ±4 mM, respectively) concentrations. Control incubations were also performed, with only methane, high sulfate, or high sulfide. Methane oxidation was monitored and growth of subtypes ANME-1, ANME-2a/b, and ANME-2c assessed using qPCR analysis. A preliminary archaeal community analysis was performed to gain insight into the ecological and taxonomic diversity. Almost all of the incubations with methane had methane oxidation activity, with the exception of the incubations with combined low sulfate and high sulfide concentrations. Sulfide inhibition occurred only with low sulfate concentrations, which could be due to the lower Gibbs free energy available as well as sulfide toxicity. ANME-2a/b appears to mainly grow in incubations which had high sulfate levels and methane oxidation activity, whereas ANME-1 did not show this distinction. ANME-2c only grew in incubations with only sulfate addition. These findings are consistent with previously published in situ profiling analysis of ANME subclusters in different marine sediments. Interestingly, since all ANME subtypes also grew in incubations with only methane or sulfate addition, ANME may also be able to perform anaerobic methane oxidation under substrate limited conditions or alternatively perform additional metabolic processes. PMID

  4. A Priori Method of Using Photon Activation Analysis to Determine Unknown Trace Element Concentrations in NIST Standards

    SciTech Connect

    Green, Jaromy; Sun Zaijing; Wells, Doug; Benson, Buck; Maschner, Herb

    2009-03-10

    Photon activation analysis detected elements in two NIST standards that did not have reported concentration values. A method is currently being developed to infer these concentrations by using scaling parameters and the appropriate known quantities within the NIST standard itself. Scaling parameters include: threshold, peak and endpoint energies; photo-nuclear cross sections for specific isotopes; Bremstrahlung spectrum; target thickness; and photon flux. Photo-nuclear cross sections and energies from the unknown elements must also be known. With these quantities, the same integral was performed for both the known and unknown elements resulting in an inference of the concentration of the un-reported element based on the reported value. Since Rb and Mn were elements that were reported in the standards, and because they had well-identified peaks, they were used as the standards of inference to determine concentrations of the unreported elements of As, I, Nb, Y, and Zr. This method was tested by choosing other known elements within the standards and inferring a value based on the stated procedure. The reported value of Mn in the first NIST standard was 403{+-}15 ppm and the reported value of Ca in the second NIST standard was 87000 ppm (no reported uncertainty). The inferred concentrations were 370{+-}23 ppm and 80200{+-}8700 ppm respectively.

  5. Impact of physical activity and cardiovascular fitness on total homocysteine concentrations in European adolescents: The HELENA study.

    PubMed

    Benser, Jasmin; Valtueña, Jara; Ruiz, Jonatan R; Mielgo-Ayuso, Juan; Breidenassel, Christina; Vicente-Rodriguez, German; Ferrari, Marika; Widhalm, Kurt; Manios, Yannis; Sjöström, Michael; Molnar, Denes; Gómez-Martínez, Sonia; Kafatos, Antony; Palacios, Gonzalo; Moreno, Luis A; Castillo, Manuel J; Stehle, Peter; González-Gross, Marcela

    2015-01-01

    We examined the association of physical activity (PA), cardiovascular fitness (CVF) and fatness with total homocysteine (tHcy) concentrations in European adolescents. The present study comprised 713 European adolescents aged 14.8 ± 1.2 y (females 55.3%) from the multicenter HELENA cross-sectional study. PA was assessed through accelerometry, CVF by the 20-m shuttle run test, and body fat by skinfold thicknesses with the Slaughter equation. Plasma folate, cobalamin, and tHcy concentrations were measured. To examine the association of tHcy with PA, CVF, and fatness after controlling for a set of confounders including age, maturity, folate, cobalamin, creatinine, smoking, supplement use, and methylenetetrahydrofolate reductase 677 genotype (CC 47%, CT 43%, TT 10%), bivariate correlations followed by multiple regression models were performed. In the bivariate correlation analysis, tHcy concentrations were slightly negatively correlated (p<0.05) with CVF in females (measured both by stages: r=-0.118 and by VO2max: r=-0.102) and positively with body mass index (r=0.100). However, daily time spent with moderate and vigorous PA showed a weak positive association with tHcy in females (p<0.05). tHcy concentrations showed a tendency to decrease with increasing CVF and increase with increasing BMI in female European adolescents. However, tHcy concentrations were positively associated with moderate and vigorous PA in female European adolescents. PMID:25994139

  6. Development and Validation of a Model to Predict Aerosol Breathing Zone Concentrations During Common Outdoor Activities

    EPA Science Inventory

    Research has been conducted on aerosol emission rates during various activities as well as aerosol transport into the breathing zone under idealized conditions. However, there has been little effort to link the two into a model for predicting a person’s breathing zone concentrat...

  7. Influence of age and caloric restriction on liver glycolytic enzyme activities and metabolite concentrations in mice.

    PubMed

    Hagopian, Kevork; Ramsey, Jon J; Weindruch, Richard

    2003-03-01

    The influence of caloric restriction (CR) from 2 months of age on the activities of liver glycolytic enzymes and metabolite levels was studied in young and old mice. Livers were sampled 48 h after the last scheduled feeding time. Old mice on CR showed significant decreases in the activities of all the enzymes studied, except for aldolase, triosephosphate isomerase and phosphoglycerate mutase, which were unchanged. The metabolites glucose, glucose-6-phosphate, fructose-6-phosphate, pyruvate and lactate were lower while fructose-1,6-bisphosphate, glyceraldehyde-3-phosphate, dihydroxyacetone phosphate, 3-phosphoglycerate and phosphoenolpyruvate were increased in old CR. Young mice on CR also showed reduced enzyme activities, except for aldolase, triosephosphate isomerase and enolase which were unchanged when compared with young controls. The metabolites glucose, glucose-6-phosphate, fructose-6-phosphate and pyruvate were decreased when compared with young controls, while phosphoenolpyruvate was increased. Ketone bodies increased (65%) in old, but not young, CR mice while fructose-2,6-bisphosphate decreased in both young (22%) and old CR (28%) mice. The results indicate that decreased hepatic glucose levels in CR mice are associated with decreased enzyme activities but not a uniform decrease in metabolite levels. Increased ketone body levels indicate increased utilization of non-carbohydrate fuels while decreased fructose-2,6-bisphosphate level suggests its importance in the control of glycolysis in CR. PMID:12581789

  8. Heavy metal concentrations and enzymatic activities in the functional zone sediments of Haizhou Bay, Lianyungang, Jiangsu, China.

    PubMed

    Li, Yu; Liu, Fu-cheng

    2015-11-01

    Surface sediments were collected at 31 sites covering five functional zones of Haizhou Bay, Lianyungang, Jiangsu, China. Heavy metal concentrations and enzymatic activity of phosphatase and urease were determined on a dry-weight basis of sediments. Metal concentrations in sediments were comparable to the Chinese National Standard of Marine Sediment Quality and were as follows: Cu, 8.60-55.8 mg kg(-1); Zn, 107-384 mg kg(-1); Pb, 33.6-200 mg kg(-1); Cd, 0.24-2.57 mg kg(-1); Cr, 30.3-92.1 mg kg(-1); As, 12.9-110 mg kg(-1); Ni, 15.8-49.6 mg kg(-1); Mn, 379-1272 mg kg(-1); and Fe, 13,790-38,240 mg kg(-1). A geoaccumulation index (I geo) was calculated to help researchers understand the status of pollutants in the sediments. I geo showed that Cd and As contamination existed in the study area. The mobility of the metals and the relationship between heavy metal concentrations of chemical fractions and enzymatic activities were also investigated. Results showed that Cd and Mn had higher mobility than other metals, and enzymatic activities may play an important role in controlling the bioavailability and transformation trend of heavy metals from one fraction to another in sediments. PMID:26431704

  9. Activity concentration of natural radionuclides and radon and thoron exhalation rates in rocks used as decorative wall coverings in Japan.

    PubMed

    Iwaoka, Kazuki; Hosoda, Masahiro; Tabe, Hiroyuki; Ishikawa, Tetsuo; Tokonami, Shinji; Yonehara, Hidenori

    2013-01-01

    In Japan, many dwellings have decorative wall coverings made from granite, andesite, tuff, gabbro, and marble. However, information regarding activity concentrations and radon (Rn) and thoron (Rn) exhalation rates for such rocks is very scarce. Therefore, samples of the granite, andesite, tuff, and marble that are used as wall coverings in Japan were collected from mining companies, and their activity concentrations and Rn and Rn exhalation rates were measured. Dose estimations for inhabitants living in houses built with these materials were also carried out. The activity concentration of natural radionuclides in all the materials was lower than the critical values described by the International Atomic Energy Agency (IAEA) (10,000 Bq kg for K and 1,000 Bq kg for all other radionuclides of natural origin). The maximum values of Rn and Rn mass exhalation rates for the granite samples were 0.12 and 430 mBq kg s, and those for the area exhalation rates were 1.8 and 6300 mBq m s, respectively; these values are higher than those for other samples. The maximum value of effective doses to inhabitants was 0.68 mSv y, which is lower than the intervention exemption level (1 mSv y) given in the International Commission on Radiological Protection (ICRP) Publication 82. PMID:23192085

  10. Estimation of (41)Ar activity concentration and release rate from the TRIGA Mark-II research reactor.

    PubMed

    Hoq, M Ajijul; Soner, M A Malek; Rahman, A; Salam, M A; Islam, S M A

    2016-03-01

    The BAEC TRIGA research reactor (BTRR) is the only nuclear reactor in Bangladesh. Bangladesh Atomic Energy Regulatory Authority (BAERA) regulations require that nuclear reactor licensees undertake all reasonable precautions to protect the environment and the health and safety of persons, including identifying, controlling and monitoring the release of nuclear substances to the environment. The primary activation product of interest in terms of airborne release from the reactor is (41)Ar. (41)Ar is a noble gas readily released from the reactor stacks and most has not decayed by the time it moves offsite with normal wind speed. Initially (41)Ar is produced from irradiation of dissolved air in the primary water which eventually transfers into the air in the reactor bay. In this study, the airborne radioisotope (41)Ar generation concentration, ground level concentration and release rate from the BTRR bay region are evaluated theoretically during the normal reactor operation condition by several governing equations. This theoretical calculation eventually minimizes the doubt about radiological safety to determine the radiation level for (41)Ar activity whether it is below the permissible limit or not. Results show that the estimated activity for (41)Ar is well below the maximum permissible concentration limit set by the regulatory body, which is an assurance for the reactor operating personnel and general public. Thus the analysis performed within this paper is so much effective in the sense of ensuring radiological safety for working personnel and the environment. PMID:26736180

  11. Assessing the correlation between anaerobic toluene degradation activity and bssA concentrations in hydrocarbon-contaminated aquifer material.

    PubMed

    Kazy, Sufia K; Monier, Amy L; Alvarez, Pedro J J

    2010-09-01

    The assessment of biodegradation activity in contaminated aquifers is critical to demonstrate the performance of bioremediation and natural attenuation and to parameterize models of contaminant plume dynamics. Real time quantitative PCR (qPCR) was used to target the catabolic bssA gene (coding for benzylsuccinate synthase) and a 16S rDNA phylogenetic gene (for total Bacteria) as potential biomarkers to infer on anaerobic toluene degradation rates. A significant correlation (P = 0.0003) was found over a wide range of initial toluene concentrations (1-100 mg/l) between toluene degradation rates and bssA concentrations in anaerobic microcosms prepared with aquifer material from a hydrocarbon contaminated site. In contrast, the correlation between toluene degradation activity and total Bacteria concentrations was not significant (P = 0.1125). This suggests that qPCR targeting of functional genes might offer a simple approach to estimate in situ biodegradation activity, which would enhance site investigation and modeling of natural attenuation at hydrocarbon-contaminated sites. PMID:20204467

  12. YAG laser-induced structural modification in transition metal ion containing 40K{sub 2}O-40Nb{sub 2}O{sub 5}-20SiO{sub 2} glasses

    SciTech Connect

    Venkataraman, B. Harihara; Komatsu, Takayuki

    2008-10-02

    Glasses with the compositions of 40K{sub 2}O-40Nb{sub 2}O{sub 5}-20SiO{sub 2} (in mol%) containing different concentrations (0.01, 1 and 2 mol%) of NiO were prepared by a melt quenching technique. The glasses were irradiated with a continuous wave Nd:YAG laser with a wavelength of 1064 nm, and a metastable crystalline phase of KNbO{sub 3} was obtained. In 2 mol% NiO-doped glass, lines with a width of {approx}10 {mu}m are successfully patterned by laser irradiations with a power of 0.9 W and a scanning speed of 15 {mu}m/s. It is found from micro-Raman scattering spectra that the lines are composed of the metastable crystalline phase of KNbO{sub 3}. The crystallization mechanism in Nd:YAG laser-induced crystallization in the glasses is discussed in comparison with the usual crystallization in an electric furnace.

  13. Serum Paraoxonase Activity and Malondialdehyde Serum Concentrations Remain Unaffected in Response to Hydroxyurea Therapy in β-Thalassemia Patients.

    PubMed

    Zohaib, Muhammad; Ansari, Saqib H; Hashim, Zehra; Shamsi, Tahir S; Zarina, Shamshad

    2016-07-01

    β-Thalassemia is the most common hereditary disorder characterized by reduced production of β-globin chains of hemoglobin A (HbA). In recent years, hydroxyurea (HU) has shown promising therapeutic benefits in patients with β-thalassemia by fetal hemoglobin augmentation. We have analyzed effects of hydroxyurea treatment on oxidative stress in β-thalassemia patients by assessing activities of paraoxonase (PON) and arylesterase along with malondialdehyde (MDA) and total reactive oxygen species (ROS) concentrations. Blood samples from 159 individuals including 56 HU-treated and 58 untreated β-thalassemia patients and 45 healthy controls were analyzed. PON activity was found to be highest in healthy individuals (177.76 ± 4.44 U/mL) as compared to treated (52.67 ± 3.65 U/mL) and untreated (55.11 ± 3.26 U/mL) patients. A similar trend was observed in the case of arylesterase activity in normal, β-thalassemia-treated, and untreated (210.0 ± 11.25 U/mL, 163.03 ± 9.04 U/mL, 139.77 ± 10.10 U/mL) subjects. Serum MDA concentrations (2.59 ± 0.09 nmol/mL, 2.45 ± 0.08 nmol/mL, and 1.15 ± 0.05 nmol/mL) and total ROS concentrations (3.73 ± 0.20 nmol/mL, 3.54 ± 0.23 nmol/mL, and 2.45 ± 0.14 nmol/mL) were significantly elevated in both groups (untreated and treated) as compared to healthy individuals (P < .01). Oxidative stress was found to be markedly elevated in β-thalassemia patients as compared to healthy controls. Insignificant differences were, however, observed in mean concentrations of PON1 paraoxonase and arylesterase activities, serum MDA concentration and total ROS concentrations between HU-treated and untreated patients. We propose that HU therapy alone seems to be ineffective in managing oxidative stress and is likely to offer a better clinical outcome when supplemented with efficient iron chelation therapy and antioxidants. PMID:26608512

  14. Investigating the effect of electro-active ion concentration on spectral induced polarization signatures arising from biomineralization pathways

    NASA Astrophysics Data System (ADS)

    Ntarlagiannis, D.; Slater, L. D.; Williams, K. H.; Hubbard, S. S.; Wu, Y.

    2010-12-01

    Spectral induced polarization (SIP) is a proven geophysical method for detecting biomineral formation with promising applications for monitoring biogeochemical products during microbial induced sequestration of heavy metals and radionuclides in soils. SIP has been used to monitor the evolution of bioremediation-induced end-products at the uranium-contaminated U.S. Department of Energy Rifle Integrated Field Research Challenge site in Colorado. Although a significant SIP response was detected, the quantitative interpretation is non-trivial as the polarization of metallic minerals depends both on the mineral surface properties and the electrolyte chemistry. In previous experiments SIP mechanisms were studied under complex environments and individual source mechanisms could not be evaluated. Here we examine the role of electrolyte chemistry by comparing the effect of redox active / inactive ions on metallic polarization. In these abiotic experiments magnetite was used as a proxy biomineral and dispersed within columns packed with sand. Parallel columns were saturated with solutions of different concentrations of active (Fe2+) and inactive (Ca2+) ions (0.01mM-10mM) and SIP measurements made (0.1-1000 Hz). Experimental results show small, but detectable, differences in the effect of active ion and inactive ion concentration on the SIP response. To better characterize the effect of electro-active ions on metallic minerals we used a Cole - Cole type relaxation model, to describe the SIP responses. In order to better resolve the relaxation model parameters, we followed a two-step approach whereby we started with a Bayesian based inversion to resolve for the initial parameter estimates, and subsequently used these estimates as a starting model for a deterministic solution. Our results suggest that changes in the active ion concentration, in the presence of magnetite, alone are unlikely to fully explain recent SIP monitoring data from the Rifle site.

  15. Caffeine-induced increase in voluntary activation and strength of the quadriceps muscle during isometric, concentric and eccentric contractions

    PubMed Central

    Behrens, Martin; Mau-Moeller, Anett; Weippert, Matthias; Fuhrmann, Josefin; Wegner, Katharina; Skripitz, Ralf; Bader, Rainer; Bruhn, Sven

    2015-01-01

    This study investigated effects of caffeine ingestion (8 mg/kg) on maximum voluntary torque (MVT) and voluntary activation of the quadriceps during isometric, concentric and eccentric contractions. Fourteen subjects ingested caffeine and placebo in a randomized, controlled, counterbalanced, double-blind crossover design. Neuromuscular tests were performed before and 1 h after oral caffeine and placebo intake. MVTs were measured and the interpolated twitch technique was applied during isometric, concentric and eccentric contractions to assess voluntary activation. Furthermore, normalized root mean square of the EMG signal was calculated and evoked spinal reflex responses (H-reflex evoked at rest and during weak isometric voluntary contraction) as well as twitch torques were analyzed. Caffeine increased MVT by 26.4 N m (95%CI: 9.3-43.5 N m, P = 0.004), 22.5 N m (95%CI: 3.1-42.0 N m, P = 0.025) and 22.5 N m (95%CI: 2.2-42.7 N m, P = 0.032) for isometric, concentric and eccentric contractions. Strength enhancements were associated with increases in voluntary activation. Explosive voluntary strength and voluntary activation at the onset of contraction were significantly increased following caffeine ingestion. Changes in spinal reflex responses and at the muscle level were not observed. Data suggest that caffeine ingestion induced an acute increase in voluntary activation that was responsible for the increased strength regardless of the contraction mode. PMID:25969895

  16. Ambient air concentration of sulfur dioxide affects flight activity in bees

    SciTech Connect

    Ginevan, M.E.; Lane, D.D.; Greenberg, L.

    1980-10-01

    Three long-term (16 to 29 days) low-level (0.14 to 0.28 ppM) sulfur dioxide fumigations showed that exposure tothis gas has deleterious effects on male sweat bees (Lasioglossum zephrum). Although effects on mortality were equivocal, flight activity was definitely reduced. Because flight is necessary for successful mating behavior, the results suggest that sulfur dioxide air pollution could adversely affect this and doubtless other terrestrial insects.

  17. Comparison of the concentrations of phenolic constituents in cane sugar manufacturing products with their antioxidant activities.

    PubMed

    Payet, Bertrand; Shum Cheong Sing, Alain; Smadja, Jacqueline

    2006-09-20

    Polyphenol content and free radical scavenging capacity of seven kinds of sugar manufacturing products (A sugars, clear juices, syrups, massecuite, and A, B, and C molasses) were studied. Seventy-two samples were collected at different stages of the process during two sugar harvests from a local sugar factory (Bois-Rouge, La Réunion). The total phenolic content of sugar products was determined according to the Folin-Ciocalteu assay. Polyphenols of sugar products were extracted with ethyl acetate and quantified by LC-UV-ESI-MS during all of the process. ABTS and DPPH assays were applied to aqueous solution of sugar products, which exhibited interesting free radical scavenging activity. Comparatively, ethyl acetate extracts exhibited higher antioxidant activity. Multivariate analyses (principal component analysis and canonical discriminant analysis) demonstrated a significant correlation between polyphenols and antioxidant activity. Moreover, it was observed that the sugar process results in an increase of the phenolic content and the free radical scavenging capacity of the different products. These products and especially molasses proved to be a rich source of natural antioxidants and may represent an interesting alternative to synthetic food antioxidants. PMID:16968093

  18. Impact of Activation Treatment and CCN/IN Concentrations on Simulations of A Continental Convective System

    NASA Astrophysics Data System (ADS)

    Rothenberg, D. A.; Wang, C.

    2014-12-01

    Aerosol play an important role in mediating cloud microphysics by serving as both cloud condensation and ice nuclei (CCN and IN). In mixed-phase, deep convective clouds, these CCN and IN can alter physical processes related to droplet activation and heterogeneous freezing, affecting the dynamics, microphysics, and ultimately evolution of the cloud. However, modifying the CCN and IN budget entrained into a cloud eventually leads to many simultaneous, competing microphysical processes which make it difficult to precisely predict how cloud properties will change. Here, we study the sensitivity of a continental convective system observed during the Mid-latitude Airborne Cirrus Properties Experiment (MACPEX) in 2011 to changes in CCN and IN burden with the help of 2D and 3D cloud-resolving model simulations. We explore how the potential for convective invigoration is sensitive to the treatment of droplet activation at the cloud base by adopting an emulator of an adiabatic parcel model to parameterize the activation calculation. Furthermore, we study how changes in the IN budget can enhance the role of heterogeneous freezing and diminish the efficacy of homogeneous freezing above the -40C isotherm within the cloud. Since anvil ice is typically produced homogeneously, we also study how this shift in freezing mechanisms affects the size distributions and properties of the system's anvil cirrus. The in situ observations of anvil ice obtained during MACPEX and the ice nuclei residuals are used as a reference to constrain the simulations.

  19. Cold-active alkaline phosphatase is irreversibly transformed into an inactive dimer by low urea concentrations.

    PubMed

    Hjörleifsson, Jens Guðmundur; Ásgeirsson, Bjarni

    2016-07-01

    Alkaline phosphatase is a homodimeric metallo-hydrolase where both Zn(2+) and Mg(2+) are important for catalysis and stability. Cold-adapted alkaline phosphatase variants have high activity at low temperatures and lower thermal stability compared with variants from mesophilic hosts. The instability, and thus inactivation, could be due to loose association of the dimers and/or loosely bound Mg(2)(+) in the active site, but this has not been studied in detail for the cold-adapted variants. Here, we focus on using the intrinsic fluorescence of Trp in alkaline phosphatase from the marine bacterium Vibrio splendidus (VAP) to probe for dimerization. Trp→Phe substitutions showed that two out of the five native Trp residues contributed mostly to the fluorescence emission. One residue, 15Å away from the active site (W460) and highly solvent excluded, was phosphorescent and had a distant role in substrate binding. An additional Trp residue was introduced to the dimer interface to act as a possible probe for dimerization. Urea denaturation curves indicated that an inactive dimer intermediate, structurally equivalent to the native state, was formed before dimer dissociation took place. This is the first example of the transition of a native dimer to an inactive dimer intermediate for alkaline phosphatase without using mutagenesis, ligands, or competitive inhibition. PMID:27043172

  20. Isolated metal active site concentration and stability control catalytic CO2 reduction selectivity.

    PubMed

    Matsubu, John C; Yang, Vanessa N; Christopher, Phillip

    2015-03-01

    CO2 reduction by H2 on heterogeneous catalysts is an important class of reactions that has been studied for decades. However, atomic scale details of structure-function relationships are still poorly understood. Particularly, it has been suggested that metal particle size plays a unique role in controlling the stability of CO2 hydrogenation catalysts and the distribution of active sites, which dictates reactivity and selectivity. These studies often have not considered the possible role of isolated metal active sites in the observed dependences. Here, we utilize probe molecule diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) with known site-specific extinction coefficients to quantify the fraction of Rh sites residing as atomically dispersed isolated sites (Rhiso), as well as Rh sites on the surface of Rh nanoparticles (RhNP) for a series of TiO2 supported Rh catalysts. Strong correlations were observed between the catalytic reverse water gas shift turn over frequency (TOF) and the fraction of Rhiso sites and between catalytic methanation TOF and the fraction of RhNP sites. Furthermore, it was observed that reaction condition-induced disintegration of Rh nanoparticles, forming Rhiso active sites, controls the changing reactivity with time on stream. This work demonstrates that isolated atoms and nanoparticles of the same metal on the same support can exhibit uniquely different catalytic selectivity in competing parallel reaction pathways and that disintegration of nanoparticles under reaction conditions can play a significant role in controlling stability. PMID:25671686

  1. Positron emission mammography (PEM): Effect of activity concentration, object size, and object contrast on phantom lesion detection

    SciTech Connect

    MacDonald, Lawrence R.; Wang, Carolyn L.; Eissa, Marna; Haseley, David; Kelly, Mary M.; Liu, Franklin; Parikh, Jay R.; Beatty, J. David; Rogers, James V.

    2012-10-15

    Purpose: To characterize the relationship between lesion detection sensitivity and injected activity as a function of lesion size and contrast on the PEM (positron emission mammography) Flex Solo II scanner using phantom experiments. Methods: Phantom lesions (spheres 4, 8, 12, 16, and 20 mm diameter) were randomly located in uniform background. Sphere activity concentrations were 3 to 21 times the background activity concentration (BGc). BGc was a surrogate for injected activity; BGc ranged from 0.44-4.1 kBq/mL, corresponding to 46-400 MBq injections. Seven radiologists read 108 images containing zero, one, or two spheres. Readers used a 5-point confidence scale to score the presence of spheres. Results: Sensitivity was 100% for lesions {>=}12 mm under all conditions except for one 12 mm sphere with the lowest contrast and lowest BGc (60% sensitivity). Sensitivity was 100% for 8 mm spheres when either contrast or BGc was high, and 100% for 4 mm spheres only when both contrast and BGc were highest. Sphere contrast recovery coefficients (CRC) were 49%, 34%, 26%, 14%, and 2.8% for the largest to smallest spheres. Cumulative specificity was 98%. Conclusions: Phantom lesion detection sensitivity depends more on sphere size and contrast than on BGc. Detection sensitivity remained {>=}90% for injected activities as low as 100 MBq, for lesions {>=}8 mm. Low CRC in 4 mm objects results in moderate detection sensitivity even for 400 MBq injected activity, making it impractical to optimize injected activity for such lesions. Low CRC indicates that when lesions <8 mm are observed on PEM images they are highly tracer avid with greater potential of clinical significance. High specificity (98%) suggests that image statistical noise does not lead to false positive findings. These results apply to the 85 mm thick object used to obtain them; lesion detectability should be better (worse) for thinner (thicker) objects based on the reduced (increased) influence of photon attenuation.

  2. Seawater Polluted with Highly Concentrated Polycyclic Aromatic Hydrocarbons Suppresses Osteoblastic Activity in the Scales of Goldfish, Carassius auratus.

    PubMed

    Suzuki, Nobuo; Sato, Masayuki; Nassar, Hossam F; Abdel-Gawad, Fagr Kh; Bassem, Samah M; Yachiguchi, Koji; Tabuchi, Yoshiaki; Endo, Masato; Sekiguchi, Toshio; Urata, Makoto; Hattori, Atsuhiko; Mishima, Hiroyuki; Shimasaki, Youhei; Oshima, Yuji; Hong, Chun-Sang; Makino, Fumiya; Tang, Ning; Toriba, Akira; Hayakawa, Kazuichi

    2016-08-01

    We have developed an original in vitro bioassay using teleost scale, that has osteoclasts, osteoblasts, and bone matrix as each marker: alkaline phosphatase (ALP) for osteoblasts and tartrate-resistant acid phosphatase (TRAP) for osteoclasts. Using this scale in vitro bioassay, we examined the effects of seawater polluted with highly concentrated polycyclic aromatic hydrocarbons (PAHs) and nitro-polycyclic aromatic hydrocarbons (NPAHs) on osteoblastic and osteoclastic activities in the present study. Polluted seawater was collected from two sites (the Alexandria site on the Mediterranean Sea and the Suez Canal site on the Red Sea). Total levels of PAHs in the seawater from the Alexandria and Suez Canal sites were 1364.59 and 992.56 ng/l, respectively. We were able to detect NPAHs in both seawater samples. Total levels of NPAHs were detected in the seawater of the Alexandria site (12.749 ng/l) and the Suez Canal site (3.914 ng/l). Each sample of polluted seawater was added to culture medium at dilution rates of 50, 100, and 500, and incubated with the goldfish scales for 6 hrs. Thereafter, ALP and TRAP activities were measured. ALP activity was significantly suppressed by both polluted seawater samples diluted at least 500 times, but TRAP activity did not change. In addition, mRNA expressions of osteoblastic markers (ALP, osteocalcin, and the receptor activator of the NF-κB ligand) decreased significantly, as did the ALP enzyme activity. In fact, ALP activity decreased on treatment with PAHs and NPAHs. We conclude that seawater polluted with highly concentrated PAHs and NPAHs influences bone metabolism in teleosts. PMID:27498800

  3. Effect of exercise on erythrocyte count and blood activity concentration after technetium-99m in vivo red blood cell labeling

    SciTech Connect

    Konstom, M.A.; Tu'meh, S.; Wynne, J.; Beck, J.R.; Kozlowski, J.; Holman, B.L.

    1982-09-01

    The effects of exercise on blood radiotracer concentration after technetium-99m in vivo red blood cell labeling was studied. After red blood cell labeling, 13 subjects underwent maximal supine bicycle exercise. Radioactivity, analyzed with a well counter, was measured in heparinized venous blood samples drawn at rest and during peak exercise. Changes in activity were compared with changes in erythrocyte count. Activity and erythrocyte counts increased in erythrocyte count (r=0.78), but did not correlate with either duration of exercise or maximal heart rate. Twenty minutes after termination of exercise, activity and erythrocyte count had decreased from peak exercise values but remained higher than preexercise values. In nine nonexercised control subjects, samples drawn 20 minutes apart showed no change in activity or in erythrocyte count. It was concluded that exercise increases blood activity, primarily because of an increase in erythrocyte count. During radionuclide ventriculography, blood activity must be measured before and after any intervention, particularly exercise, before a change in left ventricular activity can be attributed to a change in left ventricular volume.

  4. Phosphoserine phosphatase activity is elevated and correlates negatively with plasma d-serine concentration in patients with schizophrenia.

    PubMed

    Ozeki, Yuji; Sekine, Masae; Fujii, Kumiko; Watanabe, Takashi; Okayasu, Hiroaki; Takano, Yumiko; Shinozaki, Takahiro; Aoki, Akiko; Akiyama, Kazufumi; Homma, Hiroshi; Shimoda, Kazutaka

    2016-03-30

    The pathophysiology of schizophrenia may involve N-methyl-D-aspartate receptor (NMDAR) hypofunction. D-3serine and glycine are endogenous l-serine-derived NMDAR co-agonists. We hypothesized that the l-serine synthesis pathway could be involved in schizophrenia. We measured the activity of phosphoserine phosphatase (PSP), a rate-limiting enzyme in l-serine synthesis, in peripheral blood mononuclear cells of 54 patients with schizophrenia and 49 normal control subjects. Plasma amino acid (l-serine, d-serine, glycine, glutamine, and glutamate) levels were measured by high performance liquid chromatography. Peripheral blood mRNA expression levels of PHGDH, PSAT1, PSP, and SR, determined by quantitative real-time PCR were compared between patients and controls. PSP activity was higher in patients than in controls, especially in male patients. In male patients, the plasma l-serine concentration was higher than that in controls. In patients, PSP activity was negatively correlated with plasma d-serine and glycine levels. Furthermore, PSP activity was positively correlated with plasma l-serine concentration. These results were statistically significant only in male patients. PSP, PSAT1, and PHGDH mRNA levels were lower in patients than in controls, except when the PHGDH expression level was compared with ACTB expression. In summary, we found the l-serine synthesis system to be altered in patients with schizophrenia, especially in male patients. PMID:26804975

  5. Effects of carbohydrate on the internal oxygen concentration, oxygen uptake, and nitrogenase activity in detached pea nodules

    SciTech Connect

    Monroe, J.D. ); LaRue, T.A. )

    1989-10-01

    The interaction between carbon substrates and O{sub 2} and their effects on nitrogenase activity (C{sub 2}H{sub 2}) were examined in detached nodules of pea (Pisum sativum L. cv Sparkle). The internal O{sub 2} concentration was estimated from the fractional oxygenation of leghemoglobin measured by reflectance spectroscopy. Lowering the endogenous carbohydrate content of nodules by excising the shoots 16 hours before nodule harvest or by incubating detached nodules at 100 kPa O{sub 2} for 2 hours resulted in a 2- to 10-fold increase in internal O{sub 2}, and a decline in nitrogenase activity. Conversely, when detached nodules were supplied with 100 millimolar succinate, the internal O{sub 2} was lowered. Nitrogenase activity was stimulated by succinate but only at high external O{sub 2}. Oxygen uptake increased linearly with external O{sub 2} but was affected only slightly by the carbon treatments. The apparent diffusion resistance in the nodule cortex was similar in all of the treatments. Carbon substrates can thus affect nitrogenase activity indirectly by affecting the O{sub 2} concentration within detached nodules.

  6. Effects of initial active chlorine concentrations on the Antarctic ozone spring depletion

    SciTech Connect

    Henderson, G.S.; Evans, W.F.J. ); McConnell, J.C. )

    1990-02-20

    Several one-dimensional model experiments have been conducted in order to simulate the observed downward trend of total ozone and the shape of ozone profiles in the Antarctic during the austral spring. The results underline the fact that the O{sub 3} depletion is quadratically sensitive to the amount of active chlorine, which the authors have expressed as the fraction (F) of CL{sub x} that is in active form by polar sunrise. For F = 1, this result is largely independent of the occurrence of heterogeneous chemistry after polar sunrise since all of the processing has already occurred. The main O{sub 3} loss is due to formation and photolysis of Cl{sub 2}O{sub 2}. By comparison, using Br{sub x} levels similar to currently measured values, it was found that the BrO + ClO reaction plays a less important role in O{sub 3} depletion. The depth of the O{sub 3} minimum in spring appears to be related to the vertical extent of the region chemically processed by polar stratospheric clouds as well as the absolute levels of active Cl{sub 2}; more extensive vertical regions result in larger bite outs of the O{sub 3} profile. This may account for the difference in O{sub 3} minimum between 1986 and 1987. Simulations involving downward vertical transports are unable to reproduce observed decreases in total O{sub 3}. The authors speculate that low trace gas mixing ratios of species such as N{sub 2}O may be remnants of the previous summer and fall conditions, rather than signatures of downward transport during the springtime ozone depletion.

  7. Effect of the adsorbate (Bromacil) equilibrium concentration in water on its adsorption on powdered activated carbon. Part 2: Kinetic parameters.

    PubMed

    Al Mardini, Fadi; Legube, Bernard

    2009-10-30

    The application of several monosolute equilibrium models has previously shown that Bromacil adsorption on SA-UF (Norit) powdered activated carbon (PAC) is probably effective on two types of sites. High reactivity sites were found to be 10-20 less present in a carbon surface than lower reactivity sites, according to the q(m) values calculated by isotherm models. The aims of this work were trying, primarily, to identify the kinetic-determinant stage of the sorption of Bromacil at a wide range of initial pesticide concentrations (approximately 5 to approximately 500 microg L(-1) at pH 7.8), and secondly, to specify the rate constants and other useful design parameters for the application in water treatment. It was therefore not possible to specify a priori whether the diffusion or surface reaction is the key step. It shows that many of the tested models which describe the stage of distribution or the surface reaction are correctly applied. However, the diffusivity values (D and D(0)) were found to be constant only constants for some specific experimental concentrations. The HSDM model of surface diffusion in pores was also applied but the values of the diffusion coefficient of surface (D(s)) were widely scattered and reduce significantly with the initial concentration or the equilibrium concentration in Bromacil. The model of surface reaction of pseudo-second order fitted particularly well and led to constant values which are independent of the equilibrium concentration, except for the low concentrations where the constants become significantly more important. This last observation confirms perfectly the hypothesis based on two types of sites as concluded by the equilibrium data (part 1). PMID:19560269

  8. Determining salt concentrations for equivalent water activity in reduced-sodium cheese by use of a model system.

    PubMed

    Grummer, J; Schoenfuss, T C

    2011-09-01

    The range of sodium chloride (salt)-to-moisture ratio is critical in producing high-quality cheese products. The salt-to-moisture ratio has numerous effects on cheese quality, including controlling water activity (a(w)). Therefore, when attempting to decrease the sodium content of natural cheese it is important to calculate the amount of replacement salts necessary to create the same a(w) as the full-sodium target (when using the same cheese making procedure). Most attempts to decrease sodium using replacement salts have used concentrations too low to create the equivalent a(w) due to the differences in the molecular weight of the replacers compared with salt. This could be because of the desire to minimize off-flavors inherent in the replacement salts, but it complicates the ability to conclude that the replacement salts are the cause of off-flavors such as bitter. The objective of this study was to develop a model system that could be used to measure a(w) directly, without manufacturing cheese, to allow cheese makers to determine the salt and salt replacer concentrations needed to achieve the equivalent a(w) for their existing full-sodium control formulas. All-purpose flour, salt, and salt replacers (potassium chloride, modified potassium chloride, magnesium chloride, and calcium chloride) were blended with butter and water at concentrations that approximated the solids, fat, and moisture contents of typical Cheddar cheese. Salt and salt replacers were applied to the model systems at concentrations predicted by Raoult's law. The a(w) of the model samples was measured on a water activity meter, and concentrations were adjusted using Raoult's law if they differed from those of the full-sodium model. Based on the results determined using the model system, stirred-curd pilot-scale batches of reduced- and full-sodium Cheddar cheese were manufactured in duplicate. Water activity, pH, and gross composition were measured and evaluated statistically by linear mixed model

  9. Electrochemical activation and inhibition of neuromuscular systems through modulation of ion concentrations with ion-selective membranes

    NASA Astrophysics Data System (ADS)

    Song, Yong-Ak; Melik, Rohat; Rabie, Amr N.; Ibrahim, Ahmed M. S.; Moses, David; Tan, Ara; Han, Jongyoon; Lin, Samuel J.

    2011-12-01

    Conventional functional electrical stimulation aims to restore functional motor activity of patients with disabilities resulting from spinal cord injury or neurological disorders. However, intervention with functional electrical stimulation in neurological diseases lacks an effective implantable method that suppresses unwanted nerve signals. We have developed an electrochemical method to activate and inhibit a nerve by electrically modulating ion concentrations in situ along the nerve. Using ion-selective membranes to achieve different excitability states of the nerve, we observe either a reduction of the electrical threshold for stimulation by up to approximately 40%, or voluntary, reversible inhibition of nerve signal propagation. This low-threshold electrochemical stimulation method is applicable in current implantable neuroprosthetic devices, whereas the on-demand nerve-blocking mechanism could offer effective clinical intervention in disease states caused by uncontrolled nerve activation, such as epilepsy and chronic pain syndromes.

  10. Evaluation of the treatment of reverse osmosis concentrates from municipal wastewater reclamation by coagulation and granular activated carbon adsorption.

    PubMed

    Sun, Ying-Xue; Yang, Zhe; Ye, Tao; Shi, Na; Tian, Yuan

    2016-07-01

    Reverse osmosis concentrate (ROC) from municipal wastewater reclamation reverse osmosis (mWRRO) contains elevated concentrations of contaminants which pose potential risks to aquatic environment. The treatment of ROC from an mWRRO using granular activated carbon (GAC) combined pretreatment of coagulation was optimized and evaluated. Among the three coagulants tested, ferric chloride (FeCl3) presented relatively higher DOC removal efficiency than polyaluminium chloride and lime at the same dosage and coagulation conditions. The removal efficiency of DOC, genotoxicity, and antiestrogenic activity concentration of the ROC could achieve 16.9, 18.9, and 39.7 %, respectively, by FeCl3 coagulation (with FeCl3 dosage of 180.22 mg/L), which can hardly reduce UV254 and genotoxicity normalized by DOC of the DOM with MW <5 kDa. However, the post-GAC adsorption column (with filtration velocity of 5.7 m/h, breakthrough point adsorption capacity of 0.22 mg DOC/g GAC) exhibited excellent removal efficiency on the dominant DOM fraction of MW <5 kDa in the ROC. The removal efficiency of DOC, UV254, and TDS in the ROC was up to 91.8, 96, and 76.5 %, respectively, by the FeCl3 coagulation and post-GAC adsorption. Also, the DOM with both genotoxicity and antiestrogenic activity were completely eliminated by the GAC adsorption. The results suggest that GAC adsorption combined pretreatment of FeCl3 coagulation as an efficient method to control organics, genotoxicity, and antiestrogenic activity in the ROC from mWRRO system. PMID:27032632

  11. Optoacoustic tweezers: a programmable, localized cell concentrator based on opto-thermally generated, acoustically activated, surface bubbles.

    PubMed

    Xie, Yuliang; Zhao, Chenglong; Zhao, Yanhui; Li, Sixing; Rufo, Joseph; Yang, Shikuan; Guo, Feng; Huang, Tony Jun

    2013-05-01

    We present a programmable, biocompatible technique for dynamically concentrating and patterning particles and cells in a microfluidic device. Since our technique utilizes opto-thermally generated, acoustically activated, surface bubbles, we name it "optoacoustic tweezers". The optoacoustic tweezers are capable of concentrating particles/cells at any prescribed locations in a microfluidic chamber without the use of permanent structures, rendering it particularly useful for the formation of flexible, complex cell patterns. Additionally, this technique has demonstrated excellent biocompatibility and can be conveniently integrated with other microfluidic units. In our experiments, micro-bubbles were generated by focusing a 405 nm diode laser onto a gold-coated glass chamber. By properly tuning the laser, we demonstrate precise control over the position and size of the generated bubbles. Acoustic waves were then applied to activate the surface bubbles, causing them to oscillate at an optimized frequency. The resulting acoustic radiation force allowed us to locally trap particles/cells, including 15 μm polystyrene beads and HeLa cells, around each bubble. Cell-adhesion tests were also conducted after cell concentrating to confirm the biocompatibility of this technique. PMID:23511348

  12. Physicochemical changes effected in activated sludge by the earthworm Eisenia foetida. [Concentration of heavy metals during sludge catabolism

    SciTech Connect

    Hartenstein, R.; Hartenstein, F.

    1981-09-01

    Measurements were made of some physicochemical changes effected in activated sludge by the earthworm Eisenia foetida following conversion of the sludge into wormcasts. Mineralization was accelerated 1.3-fold and 2% of the minerals were assimilated. The rate at which heavy metals were concentrated during sludge catabolism was also accelerated. Castings stabilized within 2 weeks, as indexed by respirometry. Nucleic acids, which can be used as an index of microbial biomass, were present at a greater concentration in the wormcasts than in the sludge, while the phenolic content, which may potentially serve as an index of humification, was less concentrated. Other changes included a reduction in pH and an increase in oxidation-reduction potential and cation exchange capacity. The major general effect of E. foetida on the physicochemical properties of activated sludge is to convert a material which has a relatively small surface/volume ratio into numerous particles with an overall large S/V ratio, thus accelerating decomposition, mineralization, drying, and preclusion of malodor.

  13. Exposure of Plasmodium sporozoites to the intracellular concentration of potassium enhances infectivity and reduces cell passage activity.

    PubMed

    Kumar, Kota Arun; Garcia, Celia R S; Chandran, Vandana R; Van Rooijen, N; Zhou, Yingyao; Winzeler, Elizabeth; Nussenzweig, Victor

    2007-11-01

    Malaria sporozoites migrate through several cells prior to a productive invasion that involves the formation of a parasitophorous vacuole (PV) where sporozoites undergo transformation into Exo-erythorcytic forms (EEFs). The precise mechanism leading to sporozoite activation for invasion is unknown, but prior traversal of host cells is required. During cell migration sporozoites are exposed to large shifts in K(+) concentration. We report here that incubation of sporozoites to the intracellular K(+) concentration enhances 8-10 times the infectivity of Plasmodium berghei and 4-5 times the infectivity of Plasmodium yoelli sporozoites for a hepatocyte cell line, while simultaneously decreasing cell passage activity. The K(+) enhancing effect was time and concentration dependent, and was significantly decreased by K(+) channel inhibitors. Potassium-treated P. berghei sporozoites also showed enhanced numbers of EEFs in non-permissive cell lines. Treated sporozoites had reduced infectivity for mice, but infectivity was enhanced upon Kupffer cell depletion. Transcriptional analysis of K(+) treated and control sporozoites revealed a high degree of correlation in their levels of gene expression, indicating that the observed phenotypic changes are not due to radical changes in gene transcription. Only seven genes were upregulated by more than two-fold in K(+) treated sporozoites. The highest level was noted in PP2C, a phosphatase known to dephosphorylate the AKT potassium channel in plants. PMID:17714805

  14. Size-selective concentration and label-free characterization of protein aggregates using a Raman active nanofluidic device.

    PubMed

    Choi, Inhee; Huh, Yun Suk; Erickson, David

    2011-02-21

    Trace detection and physicochemical characterization of protein aggregates have a large impact in understanding and diagnosing many diseases, such as ageing-related neurodegeneration and systemic amyloidosis, for which the formation of protein aggregates is one of the pathological hallmarks. Here we demonstrate an innovative label-free method for detecting and characterizing small amounts of early stage protein aggregates using a Raman active nanofluidic device. Sub-micrometre channels formed by a novel elastomeric collapse technique enable the separation and concentration of matured protein aggregates from small protein molecules. The Raman enhancement by gold nanoparticle clusters fixed below a micro/nanofluidic junction allows characterization of intrinsic properties of protein aggregates at concentration levels (∼fM) much lower than can be done with traditional analytical tools. With our device we show for the first time the concentration dependence of protein aggregation over these low concentration ranges. We expect that our method could facilitate definitive diagnosis and possible therapeutics of diseases at early stages. PMID:21120240

  15. Effect of Dietary Selenomethionine Supplementation on Growth Performance, Tissue Se Concentration, and Blood Glutathione Peroxidase Activity in Kid Boer Goats.

    PubMed

    Song, Yu-xuan; Hou, Jin-xing; Zhang, Lei; Wang, Jian-gang; Liu, Xiao-rui; Zhou, Zhan-qin; Cao, Bin-yun

    2015-10-01

    We used 240 kid Boer goats that were divided into six groups. The control group was fed a basal diet containing 0.05 mg of selenium (Se)/kg dry matter (DM). Trial groups received the basal diet supplemented with 0.1, 0.2, 0.3, 0.4, or 0.5 mg Se/kg DM (using a commercial selenomethionine product). Trial groups showed an improvement in growth performance (P < 0.05) despite no change in average daily feed intakes (ADFIs) (P > 0.05) compared to the control group A, quadratic model showed a correlation between glutathione peroxidase activity level in whole blood and dietary Se concentration (R(2) = 0.883, P < 0.04). The best linear model showed that increasing concentrations of Se in the blood (R(2) = 0.968, P < 0.001) and muscle (R(2) = 0.942, P < 0.001) corresponded to increasing Se concentrations in feed. Accumulation of Se in different tissues and organs corresponded to increasing Se concentrations in the diet as well as to the total time goats spent feeding on supplemented diet. Kidney and muscle tissues showed the highest and lowest accumulation of Se, respectively. Thus, Se in goat meat can be increased by adding between 0.1 and 0.5 mg/kg of selenomethionine to the diet of goats. PMID:25813835

  16. Depollution potential of three macrophytes: exudated, wall-bound and intracellular peroxidase activities plus intracellular phenol concentrations.

    PubMed

    Larue, Camille; Korboulewsky, Nathalie; Wang, Runying; Mévy, Jean-Philippe

    2010-10-01

    The aim of this study was to investigate the potential role of three macrophyte species (Iris pseudacorus, Typha latifolia and Phragmites australis) for detoxication of xenobiotics, and to study their variations with seasons or concentrations of sewage sludge from the food industry. For this purpose, some aspects of the green liver concept were explored through peroxidase measurements in three compartments in roots: intracellular, cell wall and extracellular. In addition, phenol concentrations were also measured in order to assess heavy metal detoxication potential. Enzyme activities and phenol concentrations were overall lower in winter according to the phenological stages and some sludge effects occurred. Results show that P. australis roots exuded and contained more peroxidase in all seasons: 17 U/g (1373 U/g protein), 0.8 U/g (613 U/g protein) and 4.8 U/g (1329 U/g protein) in intracellular compartments, cell wall and exudates, respectively. In contrast, the highest phenol concentration was found in I. pseudacorus roots: 3.58 mg eq. [corrected] gallic acid/g. Hence, in constructed wetlands, P. australis is suitable for organic waste water treatment, while I. pseudacorus should be used in the case of waters highly charged with heavy metals. PMID:20570142

  17. Use of factor IX concentrates in active teenagers with hemophilia B.

    PubMed

    Tagariello, Giuseppe

    2004-06-01

    This paper addresses issues specific to the treatment of teenagers with hemophilia B. All teenagers, including those with hemophilia, are at high risk of being exposed to accident-related trauma because of activities inherent within normal adolescent development. To reduce the impact of recurrent joint bleeds, studies have shown that prophylaxis should be started at an early age, with treatment individualized due to variability in patient pharmacokinetics and product recoveries. A key factor in the acceptance and success of prophylaxis in teenagers is the training given at hemophilia treatment centers regarding self-treatment dosing and infusion schedules. Both plasma-derived and recombinant products are appropriate in this cohort, depending on the patient's and family's experiences and preferences. PMID:15322451

  18. Automotive exhaust and mouse activity: relationships between pollutant concentrations and decreases in wheel running.

    PubMed

    Gage, M I

    1979-01-01

    Groups of male and female mice inhaled either clean air, 100 ppm carbon monoxide, or light-irradiated and nonirradiated automotive exhaust containing nominally 25, 50, 75, or 100 ppm carbon monoxide in three tests with exposure lasting from 4 to 7 days. Exhaust from a factory or lean-tuned engine in the first and third tests reversibly suppressed activity wheel running during exposure in mice of both sexes by as much as 78.3 and 83.1%, respectively. Light-irradiated exhaust suppressed running more than nonirradiated exhaust. For the second test, when the engine was tuned to be low in pollutants other than carbon monoxide, exhaust did not suppress running. Exposure to carbon monoxide alone only slightly decreased running in male mice, but increased running in female mice. PMID:88208

  19. Exosomal microRNA miR-92a concentration in serum reflects human brown fat activity.

    PubMed

    Chen, Yong; Buyel, Joschka J; Hanssen, Mark J W; Siegel, Franziska; Pan, Ruping; Naumann, Jennifer; Schell, Michael; van der Lans, Anouk; Schlein, Christian; Froehlich, Holger; Heeren, Joerg; Virtanen, Kirsi A; van Marken Lichtenbelt, Wouter; Pfeifer, Alexander

    2016-01-01

    Brown adipose tissue (BAT) dissipates energy and its activity correlates with leanness in human adults. (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography coupled with computer tomography (PET/CT) is still the standard for measuring BAT activity, but exposes subjects to ionizing radiation. To study BAT function in large human cohorts, novel diagnostic tools are needed. Here we show that brown adipocytes release exosomes and that BAT activation increases exosome release. Profiling miRNAs in exosomes released from brown adipocytes, and in exosomes isolated from mouse serum, we show that levels of miRNAs change after BAT activation in vitro and in vivo. One of these exosomal miRNAs, miR-92a, is also present in human serum exosomes. Importantly, serum concentrations of exosomal miR-92a inversely correlate with human BAT activity measured by (18)F-FDG PET/CT in two unique and independent cohorts comprising 41 healthy individuals. Thus, exosomal miR-92a represents a potential serum biomarker for BAT activity in mice and humans. PMID:27117818

  20. Exosomal microRNA miR-92a concentration in serum reflects human brown fat activity

    PubMed Central

    Chen, Yong; Buyel, Joschka J.; Hanssen, Mark J. W.; Siegel, Franziska; Pan, Ruping; Naumann, Jennifer; Schell, Michael; van der Lans, Anouk; Schlein, Christian; Froehlich, Holger; Heeren, Joerg; Virtanen, Kirsi A.; van Marken Lichtenbelt, Wouter; Pfeifer, Alexander

    2016-01-01

    Brown adipose tissue (BAT) dissipates energy and its activity correlates with leanness in human adults. 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography coupled with computer tomography (PET/CT) is still the standard for measuring BAT activity, but exposes subjects to ionizing radiation. To study BAT function in large human cohorts, novel diagnostic tools are needed. Here we show that brown adipocytes release exosomes and that BAT activation increases exosome release. Profiling miRNAs in exosomes released from brown adipocytes, and in exosomes isolated from mouse serum, we show that levels of miRNAs change after BAT activation in vitro and in vivo. One of these exosomal miRNAs, miR-92a, is also present in human serum exosomes. Importantly, serum concentrations of exosomal miR-92a inversely correlate with human BAT activity measured by 18F-FDG PET/CT in two unique and independent cohorts comprising 41 healthy individuals. Thus, exosomal miR-92a represents a potential serum biomarker for BAT activity in mice and humans. PMID:27117818

  1. Effect of granular activated carbon concentration on the content of organic matter and salt, influencing E. coli activity and survival in fluidized bed disinfection reactor.

    PubMed

    Racyte, Justina; Langenhoff, Alette A M; Ribeiro, Ana F M M R; Paulitsch-Fuchs, Astrid H; Bruning, Harry; Rijnaarts, Huub H M

    2014-10-01

    Granular activated carbon (GAC) is used in water treatment systems, typically to remove pollutants such as natural organic matter, volatile organic compounds, chlorine, taste, and odor. GAC is also used as a key component of a new technology that combines a fluidized bed reactor with radio frequency electric fields for disinfection. So far, the effects of GAC on bacteria in these fluidized bed reactors are unclear. This paper describes a systematic study of the physico-chemical changes in five microbial media compositions caused by different concentrations (23-350 g/L) of GAC, and the effects of these physico-chemical changes on the metabolic activity and survival of a model microorganism (Escherichia coli YMc10) in a fluidized bed reactor. The chemical adsorption taking place in suspensions with specific GAC changed nutritional, osmotic, and pH conditions in the investigated microbial media (LB, diluted LB, PBS, diluted PBS, and tap water), leading to a decay of the metabolic activity and survival of E. coli. Especially media that are poor in organic and mineral compounds (e.g., PBS) with suspended GAC showed a concentration decay of 3.5 Log CFU/mL E. coli after 6 h. Organic compounds depletion and severe pH variation were enhanced in the presence of higher GAC concentrations. PMID:24729067

  2. Metal Concentrations in Two Commercial Tuna Species from an Active Volcanic Region in the Mid-Atlantic Ocean.

    PubMed

    Torres, Paulo; Rodrigues, Armindo; Soares, Lília; Garcia, Patrícia

    2016-02-01

    Concentrations of cadmium (Cd), mercury (Hg), and lead [Pb (µg g(-1) wet weight)] were determined in liver and muscle samples of 15 bigeye (Thunnus obesus) and 15 skipjack tunas (Katsuwonus pelamis) caught over an active volcanic region in the Mid-Atlantic Ocean (Azores, Portugal) and evaluated regarding consumption safety. None of the muscle samples (edible part) exceeded the European Union (EU) maximum limits (MLs) for Hg and Pb. Cd concentrations in muscle were much greater than EU MLs with 53 and 26 % of the bigeye tuna and skipjack tuna, respectively, in exceedance of the limits. Results obtained in this work, together with other studies in the same region, support the existence of an important volcanic source of Cd in waters of the Mid-Atlantic region, which should be carefully monitored given the importance of many commercial marine species for human consumption, mainly in Europe. PMID:26681184

  3. Selectivity loss of Pt/CeO{sub 2} PROX catalysts at low CO concentrations: mechanism and active site study.

    SciTech Connect

    Polster, C. S.; Zhang, R.; Cyb, M. T.; Miller, J. T.; Baertsch, C. D.

    2010-07-01

    CO and H{sub 2} oxidation were studied over a series of Pt/CeO{sub 2} catalysts with differing Pt loadings and dispersions. Kinetic rate analysis confirms the presence of dual Langmuir-Hinshelwood (L-H) and Mars and van Krevelen (M-vK) pathways and is used to explain the loss in CO oxidation selectivity at low CO concentrations. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) shows the strong CO coverage dependence on both CO and O{sub 2} concentrations and explains the transition from L-H to M-vK reaction character. Redox site measurements are performed on Pt/CeO{sub 2} catalysts by anaerobic titrations under conditions where the M-vK pathway dominates the reaction rate. Similar redox site densities per interfacial Pt atom suggest that interfacial Pt-O-Ce sites are responsible for M-vK redox activity.

  4. Effects of nitrogen fertilization on soil nutrient concentration and phosphatase activity and forage nutrient uptake from a grazed pasture system.

    PubMed

    Dillard, Sandra Leanne; Wood, Charles Wesley; Wood, Brenda Hall; Feng, Yucheng; Owsley, Walter Frank; Muntifering, Russell Brian

    2015-05-01

    Over a 3-year period, the effect of differing N-application regimes on soil extractable-P concentration, soil phosphatase activity, and forage P uptake in a P-enriched grazed-pasture system was investigated. In the fall of each year, six 0.28-ha plots were overseeded with triticale ( × Triticosecale rimpaui Wittm.) and crimson clover (Trifolium incarnatum) into a tall fescue (Lolium arundinacea)/bermudagrass (Cynodon dactylon) sod and assigned to 1 of 3 N-fertilizer treatments (n = 2): 100% of N recommendation in a split application (100N), 50% in a single application (50N), and 0% of N recommendation (0N) for triticale. Cattle commenced grazing the following spring and grazed until May. In the summer, plots were overseeded with cowpea (Vigna unguiculata), fertilized at the same rates by reference to N recommendations for bermudagrass, and grazed by cattle until September. There were no effects of N fertilization on soil phosphatase activity, electrical conductivity, or concentrations of water-soluble P. Concentrations of extractable P decreased in plots receiving 50N, but increasing N fertilization to 100N resulted in no further reduction in extractable P. Forage biomass, foliar P concentrations, and forage P mass were not affected by N fertilization rates at the plant-community level, but responses were observed within individual forage species. Results are interpreted to mean that N fertilization at 50% of the agronomic recommendation for the grass component can increase forage P mass of specific forages and decrease soil extractable P, thus providing opportunity for decreasing P losses from grazed pasture. PMID:25728918

  5. Global Distribution of Cloud Droplet Number Concentration, Autoconversion Rate, and Aerosol Indirect Effect Under Diabatic Droplet Activation

    NASA Technical Reports Server (NTRS)

    Barahona, Donifan; Sotiropoulou, Rafaella; Nenes, Athanasios

    2011-01-01

    This study presents a global assessment of the sensitivity of droplet number to diabatic activation (i.e., including effects from entrainment of dry air) and its first-order tendency on indirect forcing and autoconversion. Simulations were carried out with the NASA Global Modeling Initiative (GMI) atmospheric and transport model using climatological metereorological fields derived from the former NASA Data Assimilation Office (DAO), the NASA Finite volume GCM (FVGCM) and the Goddard Institute for Space Studies version II (GISS) GCM. Cloud droplet number concentration (CDNC) is calculated using a physically based prognostic parameterization that explicitly includes entrainment effects on droplet formation. Diabatic activation results in lower CDNC, compared to adiabatic treatment of the process. The largest decrease in CDNC (by up to 75 percent) was found in the tropics and in zones of moderate CCN concentration. This leads to a global mean effective radius increase between 0.2-0.5 micrometers (up to 3.5 micrometers over the tropics), a global mean autoconversion rate increase by a factor of 1.1 to 1.7 (up to a factor of 4 in the tropics), and a 0.2-0.4 W m(exp -2) decrease in indirect forcing. The spatial patterns of entrainment effects on droplet activation tend to reduce biases in effective radius (particularly in the tropics) when compared to satellite retrievals. Considering the diabatic nature of ambient clouds, entrainment effects on CDNC need to be considered in GCM studies of the aerosol indirect effect.

  6. Concentration dependent effects of commonly used pesticides on activation versus inhibition of the quince (Cydonia Oblonga) polyphenol oxidase.

    PubMed

    Fattouch, Sami; Raboudi-Fattouch, Faten; Ponce, José Vicente Gil; Forment, Josep Vicent; Lukovic, Dunja; Marzouki, Nejib; Vidal, Daniel Ramón

    2010-03-01

    Polyphenol oxidase (PPO) catalyzes the oxidation of o-diphenols to their respective quinones which undergo autopolymerization and form dark pigments. The interaction of PPO with various substrates and effectors remains the focus of intensive investigations due to the enzyme's key role in pigments biosynthesis including animal melanogenesis and fruit/fungi enzymatic browning. In this study, the effect of a range of commonly used pesticides on the enzyme activity has been evaluated using the purified quince (Cydonia oblonga Miller) PPO. The biochemical analysis showed that, in the presence of high pesticide concentrations, the enzyme was competitively inhibited, particularly with benomyl, carbaryl, deltamethrine and parathion methyl for which inhibition constants (K(i)) were 8.3, 5.7, 12 and 4 microM, respectively. At lower pesticide concentrations (2-10 microM), however, the catecholase activity was significantly activated (p<0.01), suggesting a homotropic behavior of these chemical compounds. Furthermore, the use of in silico structure-based analyses, known as computational docking, highlighted the nature of the PPO-pesticides interactions and confirmed the in vitro observations. Catechol substrate and parathion methyl inhibitor showed lower total energy scores of -120.06 and -117.4 3 kcal mol(-1), indicating that these ligands had higher PPO-binding affinities. The obtained data bring to light new pesticide functional features of great interest in the medicinal, agro-chemical and environmental circles. PMID:20060877

  7. Activation of G protein by opioid receptors: role of receptor number and G-protein concentration.

    PubMed

    Remmers, A E; Clark, M J; Alt, A; Medzihradsky, F; Woods, J H; Traynor, J R

    2000-05-19

    The collision-coupling model for receptor-G-protein interaction predicts that the rate of G-protein activation is dependent on receptor density, but not G-protein levels. C6 cells expressing mu- or delta-opioid receptors, or SH-SY5Y cells, were treated with beta-funaltrexamine (mu) or naltrindole-5'-isothiocyanate (delta) to decrease receptor number. The time course of full or partial agonist-stimulated ¿35SGTPgammaS binding did not vary in C6 cell membranes containing <1-25 pmol/mg mu-opioid receptor, or 1. 4-4.3 pmol/mg delta-opioid receptor, or in SHSY5Y cells containing 0. 16-0.39 pmol/mg receptor. The association of ¿35SGTPgammaS binding was faster in membranes from C6mu cells than from C6delta cells. A 10-fold reduction in functional G-protein, following pertussis toxin treatment, lowered the maximal level of ¿35SGTPgammaS binding but not the association rate. These data indicate a compartmentalization of opioid receptors and G protein at the cell membrane. PMID:10822058

  8. Mathematical analysis of mural thrombogenesis. Concentration profiles of platelet-activating agents and effects of viscous shear flow.

    PubMed Central

    Folie, B J; McIntire, L V

    1989-01-01

    The concentration profiles of adenosine diphosphate (ADP), thromboxane A2 (TxA2), thrombin, and von Willebrand factor (vWF) released extracellularly from the platelet granules or produced metabolically on the platelet membrane during thrombus growth, were estimated using finite element simulation of blood flow over model thrombi of various shapes and dimensions. The wall fluxes of these platelet-activating agents were estimated for each model thrombus at three different wall shear rates (100 s-1, 800 s-1, and 1,500 s-1), employing experimental data on thrombus growth rates and sizes. For that purpose, whole human blood was perfused in a parallel-plate flow chamber coated with type l fibrillar human collagen, and the kinetic data collected and analyzed by an EPl-fluorescence video microscopy system and a digital image processor. It was found that thrombin concentrations were large enough to cause irreversible platelet aggregation. Although heparin significantly accelerated thrombin inhibition by antithrombin lll, the remaining thrombin levels were still significantly above the minimum threshold required for irreversible platelet aggregation. While ADP concentrations were large enough to cause irreversible platelet aggregation at low shear rates and for small aggregate sizes, TxA2 concentrations were only sufficient to induce platelet shape change over the entire range of wall shear rates and thrombi dimensions studied. Our results also indicated that the local concentration of vWF multimers released from the platelet alpha-granules could be sufficient to modulate platelet aggregation at low and intermediate wall shear rates (less than 1,000 s-1). The sizes of standing vortices formed adjacent to a growing aggregate and the embolizing stresses and the torque, acting at the aggregate surface, were also estimated in this simulation. It was found that standing vortices developed on both sides of the thrombus even at low wall shear rates. Their sizes increased with

  9. High-performance batteries for electric-vehicle propulsion and stationary energy storage. Progress report, October 1978-September 1979. [40 kWh, Li-Al and Li-Si anodes

    SciTech Connect

    Barney, D. L.; Steunenberg, R. K.; Chilenskas, A. A.; Gay, E. C.; Battles, J. E.; Hornstra, F.; Miller, W. E.; Vissers, D. R.; Roche, M. F.; Shimotake, H.; Hudson, R.; Askew, B. A.; Sudar, S.

    1980-03-01

    The research, development, and management activities of the programs at Argonne National Laboratory (ANL) and at contractors' laboratories on high-temperature batteries during the period October 1978 to September 1979 are reported. These batteries are being developed for electric-vehicle propulsion and for stationary energy-storage applications. The present cells, which operate at 400 to 500/sup 0/C, are of a vertically oriented, prismatic design with one or more inner positive electrodes of FeS or FeS/sub 2/, facing negative electrodes of lithium-aluminum or lithium-silicon alloy, and molten LiCl-KC1 electrolyte. During this reporting period, cell and battery development work has continued at ANL and contractors' laboratories. A 40 kWh electric-vehicle battery (designated Mark IA) was fabricated and delivered to ANL for testing. During the initial heat-up, one of the two modules failed due to a short circuit. A failure analysis was conducted, and the Mark IA program completed. Development work on the next electric-vehicle battery (Mark II) was initiated at Eagle-Picher Industries, Inc. and Gould, Inc. Work on stationary energy-storage batteries during this period has consisted primarily of conceptual design studies. 107 figures, 67 tables.

  10. S-band low noise amplifier and 40 kW high power amplifier subsystems of Japanese Deep Space Earth Station

    NASA Astrophysics Data System (ADS)

    Honma, K.; Handa, K.; Akinaga, W.; Doi, M.; Matsuzaki, O.

    This paper describes the design and the performance of the S-band low noise amplifier and the S-band high power amplifier that have been developed for the Usuda Deep Space Station of the Institute of Space and Astronautical Science (ISAS), Japan. The S-band low noise amplifier consists of a helium gas-cooled parametric amplifier followed by three-stage FET amplifiers and has a noise temperature of 8 K. The high power amplifier is composed of two 28 kW klystrons, capable of transmitting 40 kW continuously when two klystrons are combined. Both subsystems are operating quite satisfactorily in the tracking of Sakigake and Suisei, the Japanese interplanetary probes for Halley's comet exploration, launched by ISAS in 1985.

  11. Crystallization and preliminary X-ray crystallographic analysis of a 40 kDa N-terminal fragment of the yeast prion-remodeling factor Hsp104

    SciTech Connect

    Lee, Sukyeong; Tsai, Francis T. F.

    2007-09-01

    An N-terminal fragment of S. cerevisiae Hsp104 has been crystallized. This is the first report of the crystallization of a eukaryotic member of the Hsp100 family of molecular chaperones. A 40 kDa N-terminal fragment of Saccharomyces cerevisiae Hsp104 was crystallized in two different crystal forms. Native 1 diffracted to 2.6 Å resolution and belonged to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 66.6, b = 75.8, c = 235.7 Å. Native 2 diffracted to 2.9 Å resolution and belonged to space group P6{sub 1}22 or P6{sub 5}22, with unit-cell parameters a = 179.1, b = 179.1, c = 69.7 Å. This is the first report of the crystallization of a eukaryotic member of the Hsp100 family of molecular chaperones.

  12. Crystallization and Preliminary X-ray Crystallographic Analysis of a 40 kDa N-Terminal Fragment of the Yeast Prion-Remodeling Factor Hsp104

    SciTech Connect

    Lee,S.; Tsai, F.

    2007-01-01

    A 40 kDa N-terminal fragment of Saccharomyces cerevisiae Hsp104 was crystallized in two different crystal forms. Native 1 diffracted to 2.6 {angstrom} resolution and belonged to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 66.6, b = 75.8, c = 235.7 {angstrom}. Native 2 diffracted to 2.9 {angstrom} resolution and belonged to space group P6{sub 1}22 or P6{sub 5}22, with unit-cell parameters a = 179.1, b = 179.1, c = 69.7 {angstrom}. This is the first report of the crystallization of a eukaryotic member of the Hsp100 family of molecular chaperones.

  13. Radioactivity concentrations in soil and dose assessment for Samsun city centre, Turkey.

    PubMed

    Tufan, Mustafa Çağatay; Bostancı, Selma

    2012-09-01

    In this study, natural gamma radioactivity levels were determined in the soil samples of the Samsun city centre by using the gamma ray spectrometry method. The analysis carried out with the high-purity germanium gamma spectrometry system has shown that average activity concentrations of (238)U, (232)Th, (40)K and (137)Cs were 19±2, 22±4, 521±23 and 15±1 Bq kg(-1), respectively. From the gamma analysis of soil samples, the average value of the absorbed gamma dose rates in air and the average value of the external annual effective dose rates were calculated as 45±4 nGy h(-1) and 55±5 µSv y(-1), respectively. The external hazard index has also been calculated and it has been found that the radiation hazard in Samsun is insignificant. PMID:22456989

  14. Antioxidant activity in mature branches of ponderosa pine (Pinus ponderosa) under long-term, low concentration ozone exposure

    SciTech Connect

    Benes, S.E.; Murphy, T.M.; Laeuchli, A. ); Anderson, P.D.; Houpis, J.L.J. )

    1990-05-01

    Antioxidant activity (superoxide dismutase, peroxidases and glutathione) is being examined in mature needle tissue of ponderosa pine exposed to elevated levels of ozone (O{sub 3}). Trees used in this study are 8-14 year-old clones produced from buds from a 70 year-old tree grafted onto seedling rootstock. Trees are exposed to O{sub 3} using a newly developed branch exposure chamber (BEC). Ozone treatments are charcoal-filtered, ambient and 2x ambient concentrations. A non-chambered branch will determine the effect of exposure chamber. Superoxide dismutase (SOD) activity measured in current-year needles in February via nitrobluetetrazolium (NBT) reduction was 138.5 {plus minus} 15 (SD) units mg{sup {minus}1} protein. The activity of guaiacol-oxidizing peroxidases was 89 {plus minus} 19 (SD) {Delta}A{sub 470} min{sup {minus}1} mg{sup {minus}1} protein. Ascorbate peroxidase and the ratio of oxidized to reduced glutathione (GSSG/GSH) are also being monitored. Antioxidant activity will be measured monthly across the ozone season (March to November) and during natural ozone episodes. Cellular antioxidant activity will be related to needle photosynthesis, respiration and stomatal conductance measured using a Licor 6200 portable photosynthesis apparatus.

  15. Acute effects of acephate and methamidophos on acetylcholinesterase activity, endocrine system and amino acid concentrations in rats.

    PubMed

    Spassova, D; White, T; Singh, A K

    2000-05-01

    Acute effects of acephate (Ace) and methamidophos (Met) on acetylcholinesterase activity, endocrine system and amino acid concentrations were studied in rats. The rats were injected intraperitoneally with Ace (500 mg/kg) or Met (5 mg/kg) and then sacrificed at 15 or 60 min after the injection (A15 and A60 for Ace and M15 and M60 for Met). The primary aim of this study was to determine whether the mammalian toxicity of Ace is solely due to its conversion to Met or the protection of Ace against Met-inhibited AChE is also an important factor. The second aim of this study was to study the effects of Ace and Met on the endocrine system and amino acid concentrations and whether or not these effects correlate with AChE inhibition and Met accumulation. The Ace or Met injected animals did not exhibit the signs of organophosphate (OP) poisoning within 15 min after the injection, but exhibited tremors at 45 min after the injection. Blood and brain AChE activity in A15 and M15 rats exhibited 55 to 75% inhibition while the enzyme activity in A60 and M60 rats exhibited 80 to 95% inhibition. Ace was metabolized to Met in rats both in vivo and in vitro. A 5 rats had significantly higher Met concentration in their liver, brain and adrenal glands compared to M 5 rats, and A60 rats had significantly higher Met concentrations in their blood, liver, brain and adrenal glands compared to M60 rats. Thus, tissue Met concentrations in Ace-treated rats were significantly higher than in Met-treated rats and the inhibition of AChE activity was not consistent with the amount of metabolically formed Met, supporting the hypothesis that the Ace protection plays a role in the overall toxicity. Ace and Met both impaired circulating blood hormone and amino acid concentrations in rats. The endocrine effects of Ace and Met differed from their cholinergic effects, and were not proportional to the amount of Met present in different tissues obtained from the treatment groups. Plasma ACTH concentration was

  16. Assessment of public exposure to naturally occurring radioactive materials from mining and mineral processing activities of Tarkwa Goldmine in Ghana.

    PubMed

    Faanu, Augustine; Ephraim, James H; Darko, Emmanuel O

    2011-09-01

    Studies have been carried out in a Goldmine in Ghana to determine the exposure of the public to naturally occurring radioactive materials from processing of gold ore. Direct gamma spectrometry and neutron activation analysis techniques were used to analyse soil, rock, water and dust samples from the mining environment. The mean activity concentrations measured for (238)U, (232)Th and (40)K in the soil/rock samples were 15.2, 26.9 and 157.1 Bq kg( - 1), respectively. For the water samples, the mean activity concentrations were 0.54 and 0.41 Bq l( - 1)) and 7.76 Bq l( - 1) for (226)Ra, (232)Th and (40)K, respectively. The mean activity concentrations measured in the dust samples were 4.90 and 2.75 μBq m( - 3) for (238)U and (232)Th, respectively. The total annual effective dose to the public was estimated to be 0.69 mSv. The results in this study compared well with typical world average values. The results indicate an insignificant exposure of the public from the activities of the Goldmine. PMID:21072583

  17. Glyphosate-based herbicides reduce the activity and reproduction of earthworms and lead to increased soil nutrient concentrations

    PubMed Central

    Gaupp-Berghausen, Mailin; Hofer, Martin; Rewald, Boris; Zaller, Johann G.

    2015-01-01

    Herbicide use is increasing worldwide both in agriculture and private gardens. However, our knowledge of potential side-effects on non-target soil organisms, even on such eminent ones as earthworms, is still very scarce. In a greenhouse experiment, we assessed the impact of the most widely used glyphosate-based herbicide Roundup on two earthworm species with different feeding strategies. We demonstrate, that the surface casting activity of vertically burrowing earthworms (Lumbricus terrestris) almost ceased three weeks after herbicide application, while the activity of soil dwelling earthworms (Aporrectodea caliginosa) was not affected. Reproduction of the soil dwellers was reduced by 56% within three months after herbicide application. Herbicide application led to increased soil concentrations of nitrate by 1592% and phosphate by 127%, pointing to potential risks for nutrient leaching into streams, lakes, or groundwater aquifers. These sizeable herbicide-induced impacts on agroecosystems are particularly worrisome because these herbicides have been globally used for decades. PMID:26243044

  18. Glyphosate-based herbicides reduce the activity and reproduction of earthworms and lead to increased soil nutrient concentrations.

    PubMed

    Gaupp-Berghausen, Mailin; Hofer, Martin; Rewald, Boris; Zaller, Johann G

    2015-01-01

    Herbicide use is increasing worldwide both in agriculture and private gardens. However, our knowledge of potential side-effects on non-target soil organisms, even on such eminent ones as earthworms, is still very scarce. In a greenhouse experiment, we assessed the impact of the most widely used glyphosate-based herbicide Roundup on two earthworm species with different feeding strategies. We demonstrate, that the surface casting activity of vertically burrowing earthworms (Lumbricus terrestris) almost ceased three weeks after herbicide application, while the activity of soil dwelling earthworms (Aporrectodea caliginosa) was not affected. Reproduction of the soil dwellers was reduced by 56% within three months after herbicide application. Herbicide application led to increased soil concentrations of nitrate by 1592% and phosphate by 127%, pointing to potential risks for nutrient leaching into streams, lakes, or groundwater aquifers. These sizeable herbicide-induced impacts on agroecosystems are particularly worrisome because these herbicides have been globally used for decades. PMID:26243044

  19. Regulation of NF-{kappa}B activity in astrocytes: effects of flavonoids at dietary-relevant concentrations

    SciTech Connect

    Spilsbury, Alison; Vauzour, David; Spencer, Jeremy P.E.; Rattray, Marcus

    2012-02-17

    Highlights: Black-Right-Pointing-Pointer We tested the hypothesis that low concentrations of flavonoids inhibit NF-{kappa}B in astrocytes. Black-Right-Pointing-Pointer Primary cultured astrocytes possess a functional {kappa}B-system, measured using luciferase assays. Black-Right-Pointing-Pointer Seven flavonoids (100 nM-1 {mu}M) failed to reduce NF-{kappa}B activity in astrocytes. Black-Right-Pointing-Pointer Four flavonoids (100 nM-1 {mu}M) failed to reduce TNFa-stimulated NF-{kappa}B activity in astrocytes. Black-Right-Pointing-Pointer (-)-Epicatechin did not regulate nuclear translocation of the NF-{kappa}B subunit, p65. -- Abstract: Neuroinflammation plays an important role in the progression of neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease. Sustained activation of nuclear transcription factor {kappa}B (NF-{kappa}B) is thought to play an important role in the pathogenesis of neurodegenerative disorders. Flavonoids have been shown to possess antioxidant and anti-inflammatory properties and we investigated whether flavonoids, at submicromolar concentrations relevant to their bioavailability from the diet, were able to modulate NF-{kappa}B signalling in astrocytes. Using luciferase reporter assays, we found that tumour necrosis factor (TNF{alpha}, 150 ng/ml) increased NF-{kappa}B-mediated transcription in primary cultures of mouse cortical astrocytes, which was abolished on co-transfection of a dominant-negative I{kappa}B{alpha} construct. In addition, TNF{alpha} increased nuclear localisation of p65 as shown by immunocytochemistry. To investigate potential flavonoid modulation of NF-{kappa}B activity, astrocytes were treated with flavonoids from different classes; flavan-3-ols ((-)-epicatechin and (+)-catechin), flavones (luteolin and chrysin), a flavonol (kaempferol) or the flavanones (naringenin and hesperetin) at dietary-relevant concentrations (0.1-1 {mu}M) for 18 h. None of the flavonoids modulated constitutive or TNF

  20. Revised estimates of construction activity and emissions: Effects on ozone and elemental carbon concentrations in southern California

    NASA Astrophysics Data System (ADS)

    Millstein, Dev E.; Harley, Robert A.

    2009-12-01

    Emissions from diesel-powered construction equipment are an important source of nitrogen oxides (NO x) and particulate matter (PM). A new emission inventory for construction equipment emissions is developed based on surveys of diesel fuel use; the revised inventory is compared to current emission inventories. California's OFFROAD model estimates are 4.5 and 3.1 times greater, for NO x and PM respectively, than the fuel-based estimates developed here. The most relevant uncertainties are the overall amount of construction activity/diesel fuel use, exhaust emission factors for PM and NO x, and the spatial allocation of emissions to county level and finer spatial scales. Construction permit data were used in this study to estimate spatial distributions of emissions; the resulting distribution is well correlated with population growth. An air quality model was used to assess the impacts of revised emission estimates. Increases of up to 15 ppb in predicted peak ozone concentrations were found in southern California. Elemental carbon and fine particle mass concentrations were in better agreement with observations using revised emission estimates, whereas negative bias in predictions of ambient NO x concentrations increased.

  1. Effect of temperature on AOB activity of a partial nitritation SBR treating landfill leachate with extremely high nitrogen concentration.

    PubMed

    Gabarró, J; Ganigué, R; Gich, F; Ruscalleda, M; Balaguer, M D; Colprim, J

    2012-12-01

    This study investigates the effects of temperature on ammonia oxidizing bacteria activity in a partial nitritation (PN) sequencing batch reactor. Stable PN was achieved in a 250 L SBR with a minimum operating volume of 111L treating mature landfill leachate containing an ammonium concentration of around 6000 mg N-NH(4)(+)L(-1) at both 25 and 35 °C. A suitable influent to feed an anammox reactor was achieved in both cases. A kinetic model was applied to study the influence of free ammonia (FA), the free nitrous acid (FNA) inhibition, and the inorganic carbon (IC) limitation. NH(4)(+) and NO(2)(-) concentrations were similar at 25 and 35 °C experiments (about 2500 mg N-NH(4)(+)L(-1) and 3500 mg N-NO(2)(-)L(-1)), FA and FNA concentrations differed due to the strong temperature dependence. FNA was the main source of inhibition at 25 °C, while at 35 °C combined FA and FNA inhibition occurred. DGGE results demonstrated that PN-SBR sludge was enriched on the same AOB phylotypes in both experiments. PMID:23079415

  2. Comparison of Active Drug Concentrations in the Pulmonary Epithelial Lining Fluid and Interstitial Fluid of Calves Injected with Enrofloxacin, Florfenicol, Ceftiofur, or Tulathromycin

    PubMed Central

    Foster, Derek M.; Martin, Luke G.; Papich, Mark G.

    2016-01-01

    Bacterial pneumonia is the most common reason for parenteral antimicrobial administration to beef cattle in the United States. Yet there is little information describing the antimicrobial concentrations at the site of action. The objective of this study was to compare the active drug concentrations in the pulmonary epithelial lining fluid and interstitial fluid of four antimicrobials commonly used in cattle. After injection, plasma, interstitial fluid, and pulmonary epithelial lining fluid concentrations and protein binding were measured to determine the plasma pharmacokinetics of each drug. A cross-over design with six calves per drug was used. Following sample collection and drug analysis, pharmacokinetic calculations were performed. For enrofloxacin and metabolite ciprofloxacin, the interstitial fluid concentration was 52% and 78% of the plasma concentration, while pulmonary fluid concentrations was 24% and 40% of the plasma concentration, respectively. The pulmonary concentrations (enrofloxacin + ciprofloxacin combined) exceeded the MIC90 of 0.06 μg/mL at 48 hours after administration. For florfenicol, the interstitial fluid concentration was almost 98% of the plasma concentration, and the pulmonary concentrations were over 200% of the plasma concentrations, exceeding the breakpoint (≤ 2 μg/mL), and the MIC90 for Mannheimia haemolytica (1.0 μg/mL) for the duration of the study. For ceftiofur, penetration to the interstitial fluid was only 5% of the plasma concentration. Pulmonary epithelial lining fluid concentration represented 40% of the plasma concentration. Airway concentrations exceeded the MIC breakpoint for susceptible respiratory pathogens (≤ 2 μg/mL) for a short time at 48 hours after administration. The plasma and interstitial fluid concentrations of tulathromcyin were lower than the concentrations in pulmonary fluid throughout the study. The bronchial concentrations were higher than the plasma or interstitial concentrations, with over 900

  3. Comparison of Active Drug Concentrations in the Pulmonary Epithelial Lining Fluid and Interstitial Fluid of Calves Injected with Enrofloxacin, Florfenicol, Ceftiofur, or Tulathromycin.

    PubMed

    Foster, Derek M; Martin, Luke G; Papich, Mark G

    2016-01-01

    Bacterial pneumonia is the most common reason for parenteral antimicrobial administration to beef cattle in the United States. Yet there is little information describing the antimicrobial concentrations at the site of action. The objective of this study was to compare the active drug concentrations in the pulmonary epithelial lining fluid and interstitial fluid of four antimicrobials commonly used in cattle. After injection, plasma, interstitial fluid, and pulmonary epithelial lining fluid concentrations and protein binding were measured to determine the plasma pharmacokinetics of each drug. A cross-over design with six calves per drug was used. Following sample collection and drug analysis, pharmacokinetic calculations were performed. For enrofloxacin and metabolite ciprofloxacin, the interstitial fluid concentration was 52% and 78% of the plasma concentration, while pulmonary fluid concentrations was 24% and 40% of the plasma concentration, respectively. The pulmonary concentrations (enrofloxacin + ciprofloxacin combined) exceeded the MIC90 of 0.06 μg/mL at 48 hours after administration. For florfenicol, the interstitial fluid concentration was almost 98% of the plasma concentration, and the pulmonary concentrations were over 200% of the plasma concentrations, exceeding the breakpoint (≤ 2 μg/mL), and the MIC90 for Mannheimia haemolytica (1.0 μg/mL) for the duration of the study. For ceftiofur, penetration to the interstitial fluid was only 5% of the plasma concentration. Pulmonary epithelial lining fluid concentration represented 40% of the plasma concentration. Airway concentrations exceeded the MIC breakpoint for susceptible respiratory pathogens (≤ 2 μg/mL) for a short time at 48 hours after administration. The plasma and interstitial fluid concentrations of tulathromcyin were lower than the concentrations in pulmonary fluid throughout the study. The bronchial concentrations were higher than the plasma or interstitial concentrations, with over 900

  4. Hemolytic complement activity and concentrations of its third component during maturation of the immune response in colostrum-deprived foals.

    PubMed

    Bernoco, M M; Liu, I K; Willits, N H

    1994-07-01

    Six foals were deprived of colostrum for the first 36 hours after birth and, instead, received reconstituted powdered milk. Five control foals suckled their dams naturally. Blood samples were obtained from all the foals after birth and at approximately weekly intervals until at least 5.5 months of age. Sera were analyzed for hemolytic complement activity, complement component C3, and correlating IgG concentration. Hemolytic complement (P = 0.0145) and C3 (P = 0.0002) values were significantly higher in colostrum-deprived foals (CDF) than in naturally nursed foals at 2 to 5 days of age. In addition, significantly (P = 0.0149) higher IgG concentration was found in CDF than in naturally nursed foals between 3 and 5.5 months of age. It was concluded that the observed high complement activity in CDF within 2 to 5 days of age may provide an alternative in immune defense for IgG-deprived foals after failure of colostral transfer. PMID:7978631

  5. 210Po and 210Pb Activity Concentrations in Cigarettes Produced in Vietnam and Their Estimated Dose Contribution Due to Smoking

    NASA Astrophysics Data System (ADS)

    Tran, Thuy-Ngan N.; Le, Cong-Hao; Chau, Van-Tao

    Smoking cigarettes contributes significantly to the increase of radiation in human body because 210Po and 210Pb exist relatively high in tobacco leaves. Therefore, these two radioisotopes in eighteen of the most frequently sold cigarette brands produced in Vietnam were examined in this study. 210Po was determined by alpha spectroscopy using a passivated implanted planar silicon (PIPS) detector after a procedure including radiochemical separation and spontaneous deposition of polonium on a copper disc (the deposition efficiency of 210Po on a copper disc was approximately 94%). Sequentially, 210Pb was determined through the ingrowth of 210Po after storing the sample solutions for approximately six months. The activity concentrations of 210Po in cigarettes ranged from 13.8 to 82.6 mBq/cigarette (the mean value was 26.4 mBq/cigarette) and the activity concentrations of 210Pb in cigarettes ranged from 13.9 to 78.8 mBq/cigarette (the mean value was 25.8 mBq/cigarette). The annual committed effective dose for smokers who smoke one pack per day was also estimated to be 295.4 µSv/year (223.0 µSv/year and 72.4 µSv/year from 210Po and 210Pb, respectively). These indicated that smoking increased the risk of developing lung cancer was approximately 60 times greater for smokers than for non-smokers.

  6. Drug−disease interaction: Crohn's disease elevates verapamil plasma concentrations but reduces response to the drug proportional to disease activity

    PubMed Central

    Sanaee, Forough; Clements, John D; Waugh, Alistair W G; Fedorak, Richard N; Lewanczuk, Richard; Jamali, Fakhreddin

    2011-01-01

    AIM Inflammation is involved in the pathogenesis of cardiovascular diseases that includes reduced response to pharmacotherapy due to altered pharmacokinetics and pharmacodynamics. It is not known if these effects exist in general in all inflammatory conditions. It also remains unknown whether in a given population the effect is a function of disease severity. We investigated whether pharmacokinetics and pharmacodynamics of a typical calcium channel inhibitor are influenced by Crohn's disease (CD), a disease for which the disease severity can be readily ranked. METHODS We administered 80 mg verapamil orally to (i) healthy control subjects (n = 9), (ii) patients with clinically quiescent CD (n = 22) and (iii) patients with clinically active CD (n = 14). Serial analysis of verapamil enantiomers (total and plasma unbound), blood pressure and electrocardiograms were recorded over 8 h post dose. The severity of CD was measured using the Harvey-Bradshaw Index. RESULTS CD substantially and significantly increased plasma verapamil concentration and in a stereoselective fashion (S, 9-fold; R, 2-fold). The elevated verapamil concentration, however, failed to result in an increased verapamil pharmacodynamic effect so that the patients with elevated verapamil concentration demonstrated no significant increase in response measured as PR interval and blood pressure. Instead, the greater the disease severity, the lower was the drug potency to prolong PR interval (r = 0.86, P < 0.0006), CONCLUSIONS CD patients with severe disease may not respond to cardiovascular therapy with calcium channel blockers. Reducing the severity increases response despite reduced drug concentration. This observation may have therapeutic implication beyond the disease and the drug studies herein. PMID:21592185

  7. Effect of bovine ABCG2 Y581S polymorphism on concentrations in milk of enrofloxacin and its active metabolite ciprofloxacin.

    PubMed

    Otero, J A; García-Mateos, D; de la Fuente, A; Prieto, J G; Álvarez, A I; Merino, G

    2016-07-01

    The ATP-binding cassette transporter G2 (ABCG2) is involved in the secretion of several drugs into milk. The bovine Y581S ABCG2 polymorphism increases the secretion into milk of the fluoroquinolone danofloxacin in Holstein cows. Danofloxacin and enrofloxacin are the fluoroquinolones most widely used in veterinary medicine. Both enrofloxacin (ENRO) and its active metabolite ciprofloxacin (CIPRO) reach milk at relatively high concentrations. The aim of this work was to study the effect of the bovine Y581S ABCG2 polymorphism on in vitro transport as well as on concentrations in plasma and in milk of ENRO and CIPRO. Experiments using cells overexpressing bovine ABCG2 showed the effects of ABCG2 on the transport of CIPRO, demonstrating more efficient in vitro transport of this antimicrobial by the S581 variant as compared with the Y581 variant. Animal studies administering 2.5mg/kg of ENRO subcutaneously to Y/Y 581 and Y/S 581 cows revealed that concentrations in plasma of ENRO and CIPRO were significantly lower in Y/S animals. Regardless of the genotype, the antimicrobial profile in milk after the administration of ENRO was predominantly of CIPRO. With respect to the genotype effects on the amounts of drugs present in milk, AUC0-24 values were more than 1.2 times higher in Y/S cows for ENRO and 2.2 times for CIPRO, indicating a greater capacity of Y581S to transfer these drugs into milk. These results emphasize the clinical relevance of this polymorphism as a factor affecting the concentrations in plasma and in milk of drugs of importance in veterinary medicine. PMID:27157572

  8. The role of reduced intracellular concentrations of active drugs in the lack of response to anticancer chemotherapy

    PubMed Central

    Marin, Jose JG; Monte, Maria J; Blazquez, Alba G; Macias, Rocio IR; Serrano, Maria A; Briz, Oscar

    2014-01-01

    A major difficulty in the treatment of cancers is the poor response of many tumors to pharmacological regimens. This situation can be accounted for by the existence of a variety of complex mechanisms of chemoresistance (MOCs), leading to reduced intracellular concentrations of active agents, changes in the molecular targets of the drugs, enhanced repair of drug-induced modifications in macromolecules, stimulation of anti-apoptotic mechanisms, and inhibition of pro-apoptotic mechanisms. The present review focuses on alterations in the expression and appearance of the genetic variants that affect the genes involved in reducing the amount of active agents inside tumor cells. These alterations can occur through two mechanisms: either by lowering uptake or enhancing efflux (so-called MOC-1a and MOC-1b, respectively), or by decreasing the activation of prodrugs or enhancing inactivation of active agents through their biotransformation (MOC-2). The development of chemosensitizers that are useful in implementing the pharmacological manipulation of these processes constitutes a challenge to modern pharmacology. Nevertheless, the important physiological roles of the most relevant genes involved in MOC-1a, MOC-1b, and MOC-2 make it difficult to prevent the side effects of chemosensitizers. A more attainable goal in this area of pharmacological enquiry is the identification of proteomic profiles that will permit oncologists to accurately predict a lack of response to a given regimen, which would be useful for adapting treatment to the personal situation of each patient. PMID:24317012

  9. Vapor pressure, speciation, and chemical activities in highly concentrated sodium borate solutions at 277 and 317{degrees}C

    SciTech Connect

    Weres, O.

    1995-05-01

    The system H{sub 2}O - B{sub 2}O{sub 3} - Na{sub 2}O has been studied experimentally at 277 and 317{degrees}C. The activities of water and boric acid have been determined at mole ratios Na/B from 0 to 1.5, and total dissolved solids 3 to 8 weight percent. The activity of boric acid has been fitted to within experimental error using a speciation model with eight complex species. This model is consistent with the model previously published by Mesmer et al. The electrolyte properties of the liquid are modeled using the Pitzer-Simonson model of very concentrated electrolyte solutions. The calculated values of water activity agree with experiment, and the activity of NaOH and pOH have also been calculated. The potassium borate system also was briefly studied at 317{degrees}C, and is adequately described by a model with five complex species. The potassium borate liquid is more alkaline at K/B = 1 than a sodium borate liquid at the same mole ratio, but pOH in the two systems is the same at lower mole ratios.

  10. 137Cs concentrations in lichens before and after the Chernobyl accident.

    PubMed

    Hofmann, W; Attarpour, N; Lettner, H; Türk, R

    1993-01-01

    137Cs activities were measured in a variety of epigeic and epiphytic lichens in Austria before and after contamination by the Chernobyl fallout. For comparison, the activity of the naturally occurring 40K was also determined in each lichen sample. The high 137Cs activities found after Chernobyl suggest that lichens are suitable and inexpensive biological detectors of the fallout pattern. PMID:8416218

  11. ATP-Sensitive K+ Channels Regulate the Concentrative Adenosine Transporter CNT2 following Activation by A1 Adenosine Receptors

    PubMed Central

    Duflot, Sylvie; Riera, Bárbara; Fernández-Veledo, Sonia; Casadó, Vicent; Norman, Robert I.; Casado, F. Javier; Lluís, Carme; Franco, Rafael; Pastor-Anglada, Marçal

    2004-01-01

    This study describes a novel mechanism of regulation of the high-affinity Na+-dependent adenosine transporter (CNT2) via the activation of A1 adenosine receptors (A1R). This regulation is mediated by the activation of ATP-sensitive K+ (KATP) channels. The high-affinity Na+-dependent adenosine transporter CNT2 and A1R are coexpressed in the basolateral domain of the rat hepatocyte plasma membrane and are colocalized in the rat hepatoma cell line FAO. The transient increase in CNT2-mediated transport activity triggered by (−)-N6-(2-phenylisopropyl)adenosine is fully inhibited by KATP channel blockers and mimicked by a KATP channel opener. A1R agonist activation of CNT2 occurs in both hepatocytes and FAO cells, which express Kir6.1, Kir6.2, SUR1, SUR2A, and SUR2B mRNA channel subunits. With the available antibodies against Kir6.X, SUR2A, and SUR2B, it is shown that all of these proteins colocalize with CNT2 and A1R in defined plasma membrane domains of FAO cells. The extent of the purinergic modulation of CNT2 is affected by the glucose concentration, a finding which indicates that glycemia and glucose metabolism may affect this cross-regulation among A1R, CNT2, and KATP channels. These results also suggest that the activation of KATP channels under metabolic stress can be mediated by the activation of A1R. Cell protection under these circumstances may be achieved by potentiation of the uptake of adenosine and its further metabolization to ATP. Mediation of purinergic responses and a connection between the intracellular energy status and the need for an exogenous adenosine supply are novel roles for KATP channels. PMID:15024061

  12. Multiple 40-kDa Heat-Shock Protein Chaperones Function in Tom70-dependent Mitochondrial Import

    PubMed Central

    Bhangoo, Melanie K.; Tzankov, Stefan; Fan, Anna C.Y.; Dejgaard, Kurt; Thomas, David Y.

    2007-01-01

    Mitochondrial preproteins that are imported via the translocase of the mitochondrial outer membrane (Tom)70 receptor are complexed with cytosolic chaperones before targeting to the mitochondrial outer membrane. The adenine nucleotide transporter (ANT) follows this pathway, and its purified mature form is identical to the preprotein. Purified ANT was reconstituted with chaperones in reticulocyte lysate, and bound proteins were identified by mass spectrometry. In addition to 70-kDa heat-shock cognate protein (Hsc70) and 90-kDa heat-shock protein (Hsp90), a specific subset of cochaperones were found, but no mitochondria-specific targeting factors were found. Interestingly, three different Hsp40-related J-domain proteins were identified: DJA1, DJA2, and DJA4. The DJAs bound preproteins to different extents through their C-terminal regions. DJA dominant-negative mutants lacking the N-terminal J-domains impaired mitochondrial import. The mutants blocked the binding of Hsc70 to preprotein, but with varying efficiency. The DJAs also showed significant differences in activation of the Hsc70 ATPase and Hsc70-dependent protein refolding. In HeLa cells, the DJAs increased new protein folding and mitochondrial import, although to different extents. No single DJA was superior to the others in all aspects, but each had a profile of partial specialization. The Hsp90 cochaperones p23 and Aha1 also regulated Hsp90–preprotein interactions. We suggest that multiple cochaperones with similar yet partially specialized properties cooperate in optimal chaperone–preprotein complexes. PMID:17596514

  13. Influence of small river derived sediment on the Northeastern South China Sea sedimentation processes in the last 40 K years

    NASA Astrophysics Data System (ADS)

    Cheng, Wan-Yen; Lin, Saulwood; Lou, Jiann-Yuh; Wei, Kuo-Yen; Liu, CharShine; Chen, Shing-Li; Wang, Yun-Shuen

    2015-04-01

    Small rivers derived particles are major source of sediment to the ocean in the present time. Small rivers in Taiwan are subjected to fast tectonic activity, high precipitation rate and erosion rate. The combined annual river particle load from small rivers on the Island of Taiwan is higher than that of the Mississippi River. A large fraction of those rivers particle may finding its way into the surrounding seas and ocean, e.g. South China Sea, East China Sea, and the Philippine Sea. Furthermore, due to the nature of particle transportation off rivers from Taiwan were connected by a number of canyon systems close by the river mouth, majority of those river particles were facilitated in delivering and deposited later further into the South China Sea deep basin. The objectives of this study are to understand spatial variations in sedimentation rates and to resolve the temporal differences in sedimentation in the Northeastern South China Sea region, and to evaluate influence of small river particles to the marginal sea. A set of cores was collected in overlying water depth within 1600 - 3300 m for mutilsensor core logging of magnetic susceptibility, density, and porosity. Foraminifera (G. sacculifer, G. conglobatus, O. universa) were picked and AMS C14 analyses for age determination. Grain size, organic carbon, carbonate and biogenic silica content were measured. The results show that large sedimentation rates difference existed in the study area. Earlier studies on sedimentation rate in the region west of our study area were in range of about 10 cm/kyr while our rates are about 20-40 cm/kyr and much higher near Taiwan. Bulk sedimentation rate were higher during the transition period between LGM and Holocene and lower during Holocene. Our results demonstrated that large quantity of particles from small rivers in Taiwan are and were major source of particle and are the dominating factor in controlling sediment deposition in the northeastern South China Sea.

  14. Effect of Elevated Salt Concentrations on the Aerobic Granular Sludge Process: Linking Microbial Activity with Microbial Community Structure▿

    PubMed Central

    Bassin, J. P.; Pronk, M.; Muyzer, G.; Kleerebezem, R.; Dezotti, M.; van Loosdrecht, M. C. M.

    2011-01-01

    The long- and short-term effects of salt on biological nitrogen and phosphorus removal processes were studied in an aerobic granular sludge reactor. The microbial community structure was investigated by PCR-denaturing gradient gel electrophoresis (DGGE) on 16S rRNA and amoA genes. PCR products obtained from genomic DNA and from rRNA after reverse transcription were compared to determine the presence of bacteria as well as the metabolically active fraction of bacteria. Fluorescence in situ hybridization (FISH) was used to validate the PCR-based results and to quantify the dominant bacterial populations. The results demonstrated that ammonium removal efficiency was not affected by salt concentrations up to 33 g/liter NaCl. Conversely, a high accumulation of nitrite was observed above 22 g/liter NaCl, which coincided with the disappearance of Nitrospira sp. Phosphorus removal was severely affected by gradual salt increase. No P release or uptake was observed at steady-state operation at 33 g/liter NaCl, exactly when the polyphosphate-accumulating organisms (PAOs), “Candidatus Accumulibacter phosphatis” bacteria, were no longer detected by PCR-DGGE or FISH. Batch experiments confirmed that P removal still could occur at 30 g/liter NaCl, but the long exposure of the biomass to this salinity level was detrimental for PAOs, which were outcompeted by glycogen-accumulating organisms (GAOs) in the bioreactor. GAOs became the dominant microorganisms at increasing salt concentrations, especially at 33 g/liter NaCl. In the comparative analysis of the diversity (DNA-derived pattern) and the activity (cDNA-derived pattern) of the microbial population, the highly metabolically active microorganisms were observed to be those related to ammonia (Nitrosomonas sp.) and phosphate removal (“Candidatus Accumulibacter”). PMID:21926194

  15. Biological regulation of receptor-hormone complex concentrations in relation to dose-response assessments for endocrine-active compounds.

    PubMed

    Andersen, M E; Barton, H A

    1999-03-01

    Some endocrine-active compounds (EACs) act as agonists or antagonists of specific hormones and may interfere with cellular control processes that regulate gene transcription. Many mechanisms controlling gene expression are universal to organisms ranging from unicellular bacteria to more complex plants and animals. One mechanism, coordinated control of batteries of gene products, is critical in adaptation of bacteria to new environments and for development and tissue differentiation in multi-cellular organisms. To coordinately activate sets of genes, all living organisms have devised molecular modules to permit transitions, or switching, between different functional states over a small range of hormone concentration, and other modules to stabilize the new state through homeostatic interactions. Both switching and homeostasis are regulated by controlling concentrations of hormone-receptor complexes. Molecular control processes for switching and homeostasis are inherently nonlinear and often utilize autoregulatory feedback loops. Among the biological processes contributing to switching phenomena are receptor autoinduction, induction of enzymes for ligand synthesis, mRNA stabilization/activation, and receptor polymerization. This paper discusses a variety of molecular switches found in animal species, devises simple quantitative models illustrating roles of specific molecular interactions in creating switching modules, and outlines the impact of these switching processes and other feedback loops for risk assessments with EACs. Quantitative simulation modeling of these switching mechanisms made it apparent that highly nonlinear dose-response curves for hormones and EACs readily arise from interactions of several linear processes acting in concert on a common control point. These nonlinear mechanisms involve amplification of response, rather than multimeric molecular interactions as in conventional Hill relationships. PMID:10330682

  16. Soluble Urokinase-Type Plasminogen Activator Receptor Plasma Concentration May Predict Susceptibility to High Altitude Pulmonary Edema.

    PubMed

    Hilty, Matthias Peter; Zügel, Stefanie; Schoeb, Michele; Auinger, Katja; Dehnert, Christoph; Maggiorini, Marco

    2016-01-01

    Introduction. Acute exposure to high altitude induces inflammation. However, the relationship between inflammation and high altitude related illness such as high altitude pulmonary edema (HAPE) and acute mountain sickness (AMS) is poorly understood. We tested if soluble urokinase-type plasminogen activator receptor (suPAR) plasma concentration, a prognostic factor for cardiovascular disease and marker for low grade activation of leukocytes, will predict susceptibility to HAPE and AMS. Methods. 41 healthy mountaineers were examined at sea level (SL, 446 m) and 24 h after rapid ascent to 4559 m (HA). 24/41 subjects had a history of HAPE and were thus considered HAPE-susceptible (HAPE-s). Out of the latter, 10/24 HAPE-s subjects were randomly chosen to suppress the inflammatory cascade with dexamethasone 8 mg bid 24 h prior to ascent. Results. Acute hypoxic exposure led to an acute inflammatory reaction represented by an increase in suPAR (1.9 ± 0.4 at SL versus 2.3 ± 0.5 at HA, p < 0.01), CRP (0.7 ± 0.5 at SL versus 3.6 ± 4.6 at HA, p < 0.01), and IL-6 (0.8 ± 0.4 at SL versus 3.3 ± 4.9 at HA, p < 0.01) in all subjects except those receiving dexamethasone. The ascent associated decrease in PaO2 correlated with the increase in IL-6 (r = 0.46, p < 0.001), but not suPAR (r = 0.27, p = 0.08); the increase in IL-6 was not correlated with suPAR (r = 0.16, p = 0.24). Baseline suPAR plasma concentration was higher in the HAPE-s group (2.0 ± 0.4 versus 1.8 ± 0.4, p = 0.04); no difference was found for CRP and IL-6 and for subjects developing AMS. Conclusion. High altitude exposure leads to an increase in suPAR plasma concentration, with the missing correlation between suPAR and IL-6 suggesting a cytokine independent, leukocyte mediated mechanism of low grade inflammation. The correlation between IL-6 and PaO2 suggests a direct effect of hypoxia, which is not the case for suPAR. However, suPAR plasma concentration measured before hypoxic exposure may predict

  17. Soluble Urokinase-Type Plasminogen Activator Receptor Plasma Concentration May Predict Susceptibility to High Altitude Pulmonary Edema

    PubMed Central

    Zügel, Stefanie; Schoeb, Michele; Auinger, Katja; Dehnert, Christoph; Maggiorini, Marco

    2016-01-01

    Introduction. Acute exposure to high altitude induces inflammation. However, the relationship between inflammation and high altitude related illness such as high altitude pulmonary edema (HAPE) and acute mountain sickness (AMS) is poorly understood. We tested if soluble urokinase-type plasminogen activator receptor (suPAR) plasma concentration, a prognostic factor for cardiovascular disease and marker for low grade activation of leukocytes, will predict susceptibility to HAPE and AMS. Methods. 41 healthy mountaineers were examined at sea level (SL, 446 m) and 24 h after rapid ascent to 4559 m (HA). 24/41 subjects had a history of HAPE and were thus considered HAPE-susceptible (HAPE-s). Out of the latter, 10/24 HAPE-s subjects were randomly chosen to suppress the inflammatory cascade with dexamethasone 8 mg bid 24 h prior to ascent. Results. Acute hypoxic exposure led to an acute inflammatory reaction represented by an increase in suPAR (1.9 ± 0.4 at SL versus 2.3 ± 0.5 at HA, p < 0.01), CRP (0.7 ± 0.5 at SL versus 3.6 ± 4.6 at HA, p < 0.01), and IL-6 (0.8 ± 0.4 at SL versus 3.3 ± 4.9 at HA, p < 0.01) in all subjects except those receiving dexamethasone. The ascent associated decrease in PaO2 correlated with the increase in IL-6 (r = 0.46, p < 0.001), but not suPAR (r = 0.27, p = 0.08); the increase in IL-6 was not correlated with suPAR (r = 0.16, p = 0.24). Baseline suPAR plasma concentration was higher in the HAPE-s group (2.0 ± 0.4 versus 1.8 ± 0.4, p = 0.04); no difference was found for CRP and IL-6 and for subjects developing AMS. Conclusion. High altitude exposure leads to an increase in suPAR plasma concentration, with the missing correlation between suPAR and IL-6 suggesting a cytokine independent, leukocyte mediated mechanism of low grade inflammation. The correlation between IL-6 and PaO2 suggests a direct effect of hypoxia, which is not the case for suPAR. However, suPAR plasma concentration measured before hypoxic exposure may predict

  18. The association of physical activity and cholesterol concentrations across different combinations of central adiposity and body mass index

    PubMed Central

    Loprinzi, Paul D.; Addoh, Ovuokerie

    2016-01-01

    Background: The purpose of this study was to investigate if those who are physically active,compared to physically inactive, have better cholesterol profiles across different combinations of body mass index (BMI) and waist circumference (WC). Methods: Data from the 1999-2006 National Health and Nutrition Examination Survey (NHANES) were used (N = 16 095). Cholesterol parameters included total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), TC/HDL-C ratio, triglycerides and at herogenic index(Log10 [triglycerides/HDL-C]). Physical activity (PA) was assessed via self-report, with BMI and WC objectively measured. Cholesterol concentrations of 6 combinations of BMI and WC were evaluated among active and inactive participants. Multivariable linear regression analysis was utilized. Results: Findings were not consistent across sex. There was little evidence to suggest an association of PA on TC across varying BMI and WC combinations. For example, among those who had an obese BMI and high WC, inactive participants did not have different TC level when compared to active participants (β = -1.2; 95% CI: -3.9-1.5, P = 0.38). There was evidence to suggest a favorable association of PA on HDL-C, triglycerides and at herogenic index across varying BMI and WC combinations. For example, among those who had an obese BMI and high WC, inactive (vs. active) participants had a lower HDL-C (βadjusted = -1.6, P < 0.01). When considering either gender, there was sufficient evidence to suggest a favorable association of PA on at least one of the evaluated cholesterol parameters for each of the BMI/WC combinations with the exception of normal BMI and high WC. Conclusion: Except for those having normal weight central obesity, PA is favorably associated with cholesterol parameters across various combinations of BMI and WC. PMID:27579256

  19. Active microbial community in gas reservoirs in the North German Plain and the effects of high CO2 concentrations

    NASA Astrophysics Data System (ADS)

    Frerichs, Janin; Gniese, Claudia; Mühling, Martin; Krüger, Martin

    2010-05-01

    From the IPCC report on global warming, it is clear that large-scale solutions are needed immediately to reduce emissions of greenhouse gases. The CO2 capture and storage offers one option for reducing the greenhouse gas emissions. Favourable CO2 storage sites are depleted gas and oil fields and thus, are currently investigated by the BMBF-Geotechnologien RECOBIO-2 project. Our study is focussing on the direct influence of high CO2 concentrations on the autochthonous microbial population and environmental parameters (e.g. availability of nutrients). The gas fields Schneeren in the 'North German Plain' is operated by Gaz de France SUEZ E&V Deutschland GmbH. The conditions in the reservoir formation waters of two bore wells differ in various geochemical parameters (pH, salinity and temperature). In previous studies the community of this gas field was described by Ehinger et al. 2009. Based on these results our study included cultivation and molecular biological approaches. Our results showed significant differences of the community structure in regional distinctions of the gas reservoir. The activity profiles of two wells differed clearly in the inducible activity after substrate addition. The fluids of well A showed a high methane production rate after the addition of methanol or acetate. Well B showed a high sulphide production after the addition of sulphate and hydrogen. The molecular biological analysis of the original fluids supports the activity profile for both sites. The community analysis via real-time PCR showed for the production well head A a higher abundances for Archaea than for B. The community at site B in contrast was dominated by Bacteria. Fluids of both wells were also incubated with high CO2 concentrations in the headspace. These enrichments showed a significant decrease of methane and sulphide production with increasing CO2 levels. Currently, the community composition is analysed to identify changes connected to increased CO2 concentrations. This

  20. Selective catalytic reduction of nitric oxide by ammonia over V{sub 2}O{sub 5}/TiO{sub 2}, V{sub 2}O{sub 5}/TiO{sub 2}/SiO{sub 2}, and V{sub 2}O{sub 5}-WO{sub 3}/TiO{sub 2} catalysts: Effect of vanadia content on the activation energy

    SciTech Connect

    Amiridis, M.D.; Solar, J.P.

    1996-03-01

    A systematic variation of the V{sub 2}O{sub 5} content of the title catalysts reveals a dependence of the activation energy of the selective catalytic reduction of nitric oxide by ammonia on the surface concentration of vanadia. A significant decrease in activation energy (from approximately 80 to 40 kJ/mol) is observed, as the vanadia surface concentration is increased (from 0.3 to 8 {micro}mol/m{sup 2}). The same results were obtained from tests conducted both in the presence and absence of H{sub 2}O and SO{sub 2}. A possible mechanistic explanation is discussed.

  1. Evaluation of neonatal exposure to cocaine on learning, activity, startle, scent marking, immobility, and plasma cocaine concentrations.

    PubMed

    Vorhees, C V; Inman-Wood, S L; Morford, L L; Reed, T M; Moran, M S; Pu, C; Cappon, G D

    2000-01-01

    Prenatal cocaine treatment produces equivocal effects on spatial learning and memory; however, no data are available on neonatal treatment as a model of human third-trimester exposure. Sprague-Dawley rats were treated on postnatal days (P) 1-10 or 11-20 with cocaine (15 mg/kg x 4 per day at 2-h intervals) or saline (P1-P20) and evaluated as adults in the Morris water maze and on tests of activity, startle, scent marking, swimming immobility, and sequential learning. Neonatal cocaine had no effect on mortality; however, early treatment reduced body weight, whereas later treatment did not. Neonatal cocaine had no effects on exploratory activity, swimming ability, sequential learning, multiday activity rhythms, scent marking, or swimming immobility, but augmented acoustic startle amplitude in the early-treated group. Neonatal cocaine also produced an interaction on spatial learning in which the cocaine early-treated males performed slightly more efficiently than controls. Plasma cocaine concentrations were significantly higher in the early-treated group than the later-treated group despite receiving the same weight-adjusted doses. It was concluded that neonatal cocaine, when administered during a stage of brain development analogous to human third trimester, induces few behavioral effects based on the assessments used in this study. PMID:10758355

  2. Antioxidant capacity and angiotensin I converting enzyme inhibitory activity of a melon concentrate rich in superoxide dismutase.

    PubMed

    Carillon, Julie; Del Rio, Daniele; Teissèdre, Pierre-Louis; Cristol, Jean-Paul; Lacan, Dominique; Rouanet, Jean-Max

    2012-12-01

    Antioxidant capacity and angiotensin 1-converting enzyme (ACE) inhibitory activity of a melon concentrate rich in superoxide dismutase (SOD-MC) were investigated in vitro. The total antioxidant capacity (TAC) was measured by the Trolox equivalent antioxidant capacity assay (TEAC), the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical assay, and the ferric reducing antioxidant power assay (FRAP). The ability of the extract to scavenge three specific reactive oxygen species (superoxide radical anion (O(2)(-)), hydroxyl radical (HO()) and hydrogen peroxide (H(2)O(2))) was also investigated in order to better evaluate its antioxidant properties. Even if the measures of TAC were relatively low, results clearly established an antioxidant potential of SOD-MC that exhibited the highest radical-scavenging activity towards O(2)(-), with a IC(50) 12-fold lower than that of H(2)O(2) or HO(). This lets hypothesis that the antioxidant potential of SOD-MC could be mainly due to its high level of SOD. Moreover, for the first time, an ACE inhibitory activity of SOD-MC (IC(50)=2.4±0.1mg/mL) was demonstrated, showing that its use as a functional food ingredient with potential preventive benefits in the context of hypertension may have important public health implications and should be carefully considered. PMID:22953857

  3. Noninvasive transcranial focal stimulation via tripolar concentric ring electrodes lessens behavioral seizure activity of recurrent pentylenetetrazole administrations in rats.

    PubMed

    Makeyev, Oleksandr; Luna-Munguía, Hiram; Rogel-Salazar, Gabriela; Liu, Xiang; Besio, Walter G

    2013-05-01

    Epilepsy affects approximately 1% of the world population. Antiepileptic drugs are ineffective in approximately 30% of patients and have side effects. We have been developing a noninvasive transcranial focal electrical stimulation with our novel tripolar concentric ring electrodes as an alternative/complementary therapy for seizure control. In this study we demonstrate the effect of focal stimulation on behavioral seizure activity induced by two successive pentylenetetrazole administrations in rats. Seizure onset latency, time of the first behavioral change, duration of seizure, and maximal seizure severity score were studied and compared for focal stimulation treated (n = 9) and control groups (n = 10). First, we demonstrate that no significant difference was found in behavioral activity for focal stimulation treated and control groups after the first pentylenetetrazole administration. Next, comparing first and second pentylenetetrazole administrations, we demonstrate there was a significant change in behavioral activity (time of the first behavioral change) in both groups that was not related to focal stimulation. Finally, we demonstrate focal stimulation provoking a significant change in seizure onset latency, duration of seizure, and maximal seizure severity score. We believe that these results, combined with our previous reports, suggest that transcranial focal stimulation may have an anticonvulsant effect. PMID:22692938

  4. macroH2A1 Histone Variants Are Depleted on Active Genes but Concentrated on the Inactive X Chromosome†

    PubMed Central

    Changolkar, Lakshmi N.; Pehrson, John R.

    2006-01-01

    Using a novel thiol affinity chromatography approach to purify macroH2A1-containing chromatin fragments, we examined the distribution of macroH2A1 histone variants in mouse liver chromatin. We found that macroH2A1 was depleted on the transcribed regions of active genes. This depletion was observed on all of the 20 active genes that we probed, with only one site showing a small amount of enrichment. In contrast, macroH2A1 was concentrated on the inactive X chromosome, consistent with our previous immunofluorescence studies. This preferential localization was seen on genes that are active in liver, genes that are inactive in liver, and intergenic regions but was absent from four regions that escape X inactivation. These results support the hypothesis that macroH2As function as transcriptional repressors. Also consistent with this hypothesis is our finding that the heterochromatin protein HP1β copurifies with the macroH2A1-containing chromatin fragments. This study presents the first detailed examination of the distribution of macroH2A1 variants on specific sequences. Our results indicate that macroH2As have complex distribution patterns that are influenced by both local factors and long-range mechanisms. PMID:16738309

  5. International Heliophysical Year and Astronomy and Space Science Activities in Arab States: Concentration on United Arab Emirates and Iraq

    NASA Astrophysics Data System (ADS)

    Al-Naimiy, Hamid M. K.; Al-Douri, Ala A. J.

    2008-12-01

    This paper summarizes International Heliophysical Year (IHY), astronomy and space sciences (ASS) activities in many Arab countries with the concentration on Iraq and UAE. The level and type of these activities differ in each country. -The paper shows also the current activities on topics related to IHY in different countries, following are suggested future Astronomy and Space Science (ASS) plans in some of these countries: -UAE Research Centre for Solar Physics, Astronomy and Space Sciences: A proposal under consideration for building a Solar Physics and Space Research Centre that may contain: Solar, radio and optical observatories, and Very Low Frequency (VLF) Receiver for remote sensing the Ionosphere on UAE region. The proposed research project will facilitate the establishment and conduct of VLF observations in the United Arab Emirate (UAE) as a part of Asia sector, thus providing a basis for comparison to facilitate global extrapolations and conclusions. -Iraqi National Astronomical Observatory (INAO): The Kurdistan Government/Universities planning to rebuilt INAO which has been destroyed during the two wars. Proposed suggestion is to build a 5-6 meters optical telescope and small solar telescope on the tope of Korek Mountain, which has excellent observing conditions.

  6. Radioactivity concentrations and dose assessment for soil samples around nuclear power plant IV in Taiwan.

    PubMed

    Tsai, Tsuey-Lin; Lin, Chun-Chih; Wang, Tzu-Wen; Chu, Tieh-Chi

    2008-09-01

    Activity concentrations and distributions of natural and man-made radionuclides in soil samples collected around nuclear power plant IV, Taiwan, were investigated for five years to assess the environmental radioactivity and characterisation of radiological hazard prior to commercial operation. The activity concentrations of radionuclides were determined via gamma-ray spectrometry using an HPGe detector. Data obtained show that the average concentrations of the (238)U and (232)Th series, and (40)K, were within world median ranges in the UNSCEAR report. The (137)Cs ranged from 2.46 +/- 0.55 to 12.13 +/- 1.31 Bq kg(-1). The terrestrial absorbed dose rate estimated by soil activity and directly measured with a thermoluminescence dosemeter (excluding cosmic rays), and the annual effective doses, were 45.63, 57.34 nGy h(-1) and 57.19 microSv, respectively. Experimental results were compared with international recommended values. Since the soil in this area is an important building material, the mean radium equivalent activity, external and inhalation hazard indices and the representative level index using various models given in the literature for the study area were 98.18 Bq kg(-1), 0.27, 0.34 and 0.73, respectively, which were below the recommended limits. Analytical results demonstrate that no radiological anomaly exists. The baseline data will prove useful and important in estimating the collective dose near the new nuclear power plant under construction in Taiwan. PMID:18714131

  7. Bio-active engineered 50 nm silica nanoparticles with bone anabolic activity: therapeutic index, effective concentration, and cytotoxicity profile in vitro

    PubMed Central

    Ha, Shin-Woo; Sikorski, James A.; Weitzmann, M. Neale; Beck, George R.

    2014-01-01

    Silica-based nanomaterials are generally considered to be excellent candidates for therapeutic applications particularly related to skeletal metabolism however the current data surrounding the safety of silica based nanomaterials is conflicting. This may be due to differences in size, shape, incorporation of composite materials, surface properties, as well as the presence of contaminants following synthesis. In this study we performed extensive in vitro safety profiling of ~50 nm spherical silica nanoparticles with OH-terminated or Polyethylene Glycol decorated surface, with and without a magnetic core, and synthesized by the Stöber method. Nineteen different cell lines representing all major organ types were used to investigate an in vitro lethal concentration (LC) and results revealed little toxicity in any cell type analyzed. To calculate an in vitro therapeutic index we quantified the effective concentration at 50% response (EC50) for nanoparticle-stimulated mineral deposition activity using primary bone marrow stromal cells (BMSCs). The EC50 for BMSCs was not substantially altered by surface or magnetic core. The calculated Inhibitory concentration 50% (IC50) for pre-osteoclasts was similar to the osteoblastic cells. These results demonstrate the pharmacological potential of certain silica-based nanomaterial formulations for use in treating bone diseases based on a favorable in vitro therapeutic index. PMID:24333519

  8. Comparing the desorption and biodegradation of low concentrations of phenanthrene sorbed to activated carbon, biochar and compost.

    PubMed

    Marchal, Geoffrey; Smith, Kilian E C; Rein, Arno; Winding, Anne; Trapp, Stefan; Karlson, Ulrich G

    2013-02-01

    Carbonaceous soil amendments are applied to contaminated soils and sediments to strongly sorb hydrophobic organic contaminants (HOCs) and reduce their freely dissolved concentrations. This limits biouptake and toxicity, but also biodegradation. To investigate whether HOCs sorbed to such amendments can be degraded at all, the desorption and biodegradation of low concentrations of (14)C-labelled phenanthrene (≤5 μg L(-1)) freshly sorbed to suspensions of the pure soil amendments activated carbon (AC), biochar (charcoal) and compost were compared. Firstly, the maximum abiotic desorption of phenanthrene from soil amendment suspensions in water, minimal salts medium (MSM) or tryptic soy broth (TSB) into a dominating silicone sink were measured. Highest fractions remained sorbed to AC (84±2.3%, 87±4.1%, and 53±1.2% for water, MSM and TSB, respectively), followed by charcoal (35±2.2%, 32±1.7%, and 12±0.3%, respectively) and compost (1.3±0.21%, similar for all media). Secondly, the mineralization of phenanthrene sorbed to AC, charcoal and compost by Sphingomonas sp. 10-1 (DSM 12247) was determined. In contrast to the amounts desorbed, phenanthrene mineralization was similar for all the soil amendments at about 56±11% of the initially applied radioactivity. Furthermore, HPLC analyses showed only minor amounts (<5%) of residual phenanthrene remaining in the suspensions, indicating almost complete biodegradation. Fitting the data to a coupled desorption and biodegradation model revealed that desorption did not limit biodegradation for any of the amendments, and that degradation could proceed due to the high numbers of bacteria and/or the production of biosurfactants or biofilms. Therefore, reduced desorption of phenanthrene from AC or charcoal did not inhibit its biodegradation, which implies that under the experimental conditions these amendments can reduce freely dissolved concentration without hindering biodegradation. In contrast, phenanthrene sorbed to compost

  9. Effects of multivalent histamine supported on gold nanoparticles: activation of histamine receptors by derivatized histamine at subnanomolar concentrations.

    PubMed

    Gasiorek, Friederike; Pouokam, Ervice; Diener, Martin; Schlecht, Sabine; Wickleder, Mathias S

    2015-10-21

    Colloidal gold nanoparticles with a functionalized ligand shell were synthesized and used as new histamine receptor agonists. Mercaptoundecanoic acid moieties were attached to the surface of the nanoparticles and derivatized with native histamine. The multivalent presentation of the immobilized ligands carried by the gold nanoparticles resulted in extremely low activation concentrations for histamine receptors on rat colonic epithelium. As a functional read-out system, chloride secretion resulting from stimulation of neuronal and epithelial histamine H1 and H2 receptors was measured in Ussing chamber experiments. These responses were strictly attributed to the histamine entities as histamine-free particles Au-MUDOLS or the monovalent ligand AcS-MUDA-HA proved to be ineffective. The vitality of the tissues used was not impaired by the nanoparticles. PMID:26289108

  10. Influence of antimicrobial subinhibitory concentrations on hemolytic activity and bacteriocin-like substances in oral Fusobacterium nucleatum.

    PubMed

    Okamoto, A C; Gaetti-Jardim, E; Cai, S; Avila-Campos, M J

    2000-04-01

    Fusobacterium nucleatum is considered for its role in colonization of initial and late microorganisms in dental plaque and for its coaggregation with other bacterial species. It is known that action of different antimicrobial substances may interfere with either virulence factors or with host-bacteria interaction. The goal of this study was to examine the influence of subinhibitory concentrations of chlorhexidine, triclosan, penicillin G and metronidazole on hemolytic activity and bacteriocin-like substance production of oral F. nucleatum. A high resistance to penicillin G was observed and 63% of the isolates were beta-lactamase positive. All the tested isolates were susceptible to metronidazole. F. nucleatum isolates grown with or without antimicrobials were alpha-hemolytics. Bacteriocin-like substance production was increased in isolates grown with penicillin G. Impaired production of hemolytic or antagonic substances can suggest a role in the regulation of oral microbiota. PMID:10872683

  11. Lipase immobilized on hydrophobic porous polymer supports prepared by concentrated emulsion polymerization and their activity in the hydrolysis of triacylglycerides.

    PubMed

    Ruckenstein, E; Wang, X

    1993-09-20

    Microporous polymer supports for the immobilization of lipase have been prepared by the polymerization of a concentrated emulsion precursor. The concentrated emulsion consists of a mixture of styrene and divinyl-benzene containing a suitable surfactant and an initiator as the continuous phase and water as the dispersed phase. The volume fraction of the latter phase was greater than 0.74, which is the volume fraction of the dispersed phase for the most compact arrangement of spheres of equal radius. The lipase from Candida rugosa has been immobilized on the internal surface of the hydrophobic microporous poly(styrene-divinyl benzene) supports and used as biocatalysts for the hydrolysis of triacylglycerides. The effects of the amount of surfactant, of the molar ratio of divinylbenzene/styrene in the continuous phase, and of the aquaphilicity of the supports on the adsorption, activity, and stability of the immobilized lipase have been investigated. The microporous poly(styrene-divinylbenzene) adsorbents constitute excellent supports for lipase because both the amount adsorbed is large and the rate of enzymatic reaction per molecule of lipase is higher for the immobilized enzyme than for the free one. PMID:18613129

  12. Nitrogen removal from wastewater and bacterial diversity in activated sludge at different COD/N ratios and dissolved oxygen concentrations.

    PubMed

    Zielińska, Magdalena; Bernat, Katarzyna; Cydzik-Kwiatkowska, Agnieszka; Sobolewska, Joanna; Wojnowska-Baryła, Irena

    2012-01-01

    The impact of the organic carbon to nitrogen ratio (chemical oxygen demand (COD)/N) in wastewater and dissolved oxygen (DO) concentration on carbon and nitrogen removal efficiency, and total bacteria and ammonia-oxidizing bacteria (AOB) communities in activated sludge in constantly aerated sequencing batch reactors (SBRs) was determined. At DO of 0.5 and 1.5 mg O2/L during the aeration phase, the efficiency of ammonia oxidation exceeded 90%, with nitrates as the main product. Nitrification and denitrification achieved under the same operating conditions suggested the simultaneous course of these processes. The most effective nitrogen elimination (above 50%) was obtained at the COD/N ratio of 6.8 and DO of 0.5 mg O2/L. Total bacterial diversity was similar in all experimental series, however, for both COD/N ratios of 6.8 and 0.7, higher values were observed at DO of 0.5 mg O2/L. The diversity and abundance of AOB were higher in the reactors with the COD/N ratio of 0.7 in comparison with the reactors with the COD/N of 6.8. For both COD/N ratios applied, the AOB population was not affected by oxygen concentration. Amplicons with sequences indicating membership of the genus Nitrosospira were the determinants of variable technological conditions. PMID:23505865

  13. Extracellular polymeric substances, microbial activity and microbial community of biofilm and suspended sludge at different divalent cadmium concentrations.

    PubMed

    Wang, Zichao; Gao, Mengchun; Wei, Junfeng; Ma, Kedong; Zhang, Jing; Yang, Yusuo; Yu, Shuping

    2016-04-01

    The differences between biofilm and suspended sludge (S-sludge) in extracellular polymeric substances (EPS), microbial activity, and microbial community in an anoxic-aerobic sequencing batch biofilm reactor (SBBR) at different concentrations of divalent cadmium (Cd(II)) were investigated. As the increase of Cd(II) concentration from 0 to 50mgL(-1), the specific ammonium oxidation rate (SAOR), specific nitrite oxidation rate (SNOR), and specific nitrate reduction rate (SNRR) of biofilm decreased from 4.85, 5.22 and 45mgNg(-1) VSSh(-1) to 1.54, 2.38 and 26mgNg(-1)VSSh(-1), respectively, and the SAOR, SNOR and SNRR of S-sludge decreased from 4.80, 5.02 and 34mgNg(-1)VSSh(-1) to 1.46, 2.20 and 17mgNg(-1)VSSh(-1), respectively. Biofilm had higher protein (PN) content in EPS than S-sludge. Contrast to S-sludge, biofilm could provide Nitrobacter vulgaris, beta proteobacterium INBAF015, and Pseudoxanthomonas mexicana with the favorable conditions of growth and reproduction. PMID:26829529

  14. Effect of two dietary concentrate levels on tenderness, calpain and calpastatin activities, and carcass merit in Waguli and Brahman steers.

    PubMed

    Ibrahim, R M; Goll, D E; Marchello, J A; Duff, G C; Thompson, V F; Mares, S W; Ahmad, H A

    2008-06-01

    The objective of this study was to compare carcass characteristics of a newly introduced breed, the Waguli (Wagyu x Tuli), with the carcass characteristics of the Brahman breed. Brahman cattle are used extensively in the Southwest of the United States because of their tolerance to adverse environmental conditions. However, Brahman carcasses are discounted according to the height of their humps because of meat tenderness issues. The Waguli was developed in an attempt to obtain a breed that retained the heat tolerance of the Brahman but had meat quality attributes similar to the Wagyu. Twenty-four animals were used. Six steers from each breed were fed a 94% concentrate diet and 6 steers from each breed were fed an 86% concentrate diet. Eight steers, 2 from each group, were harvested after 128 d, after 142 d, and after 156 d on feed. Waguli steers had larger LM, greater backfat thickness, greater marbling scores, and greater quality grades than the Brahman steers (P < 0.05). The Japanese Wagyu breed is well known for its highly marbled and tender meat, and these traits are also present in the Waguli. The Waguli had significantly lower Warner-Bratzler shear force values than the Brahman steers after 7 and 10 d of postmortem aging (P < 0.05); this difference decreased after 14 d postmortem (P = 0.2), when tenderness of the slower aging Brahman had increased to acceptable levels. Toughness of the Brahman has been associated with high levels of calpastatin in Brahman muscle, and the Waguli LM had significantly less calpastatin activity (P = 0.02) at 0 h postmortem than the Brahman LM. At 0-h postmortem, the total LM calpain activity did not differ between the Brahman and Waguli (P = 0.57). Neither diet nor days on feed had any significant effect on the 0-h postmortem calpain or at 0-h postmortem calpastatin activity, nor an effect on Warner-Bratzler shear-force values. In conclusion, LM muscle from the Waguli steers had a high degree of marbling, lower shear force values

  15. Low Concentrations of Uncouplers of Oxidative Phosphorylation Prevent Inflammatory Activation of Endothelial Cells by Tumor Necrosis Factor.

    PubMed

    Romaschenko, V P; Zinovkin, R A; Galkin, I I; Zakharova, V V; Panteleeva, A A; Tokarchuk, A V; Lyamzaev, K G; Pletjushkina, O Yu; Chernyak, B V; Popova, E N

    2015-05-01

    In endothelial cells, mitochondria play an important regulatory role in physiology as well as in pathophysiology related to excessive inflammation. We have studied the effect of low doses of mitochondrial uncouplers on inflammatory activation of endothelial cells using the classic uncouplers 2,4-dinitrophenol and 4,5,6,7-tetrachloro-2-trifluoromethylbenzimidazole, as well as the mitochondria-targeted cationic uncoupler dodecyltriphenylphosphonium (C12TPP). All of these uncouplers suppressed the expression of E-selectin, adhesion molecules ICAM1 and VCAM1, as well as the adhesion of neutrophils to endothelium induced by tumor necrosis factor (TNF). The antiinflammatory action of the uncouplers was at least partially mediated by the inhibition of NFκB activation due to a decrease in phosphorylation of the inhibitory subunit IκBα. The dynamic concentration range for the inhibition of ICAM1 expression by C12TPP was three orders of magnitude higher compared to the classic uncouplers. Probably, the decrease in membrane potential inhibited the accumulation of penetrating cations into mitochondria, thus lowering the uncoupling activity and preventing further loss of mitochondrial potential. Membrane potential recovery after the removal of the uncouplers did not abolish its antiinflammatory action. Thus, mild uncoupling could induce TNF resistance in endothelial cells. We found no significant stimulation of mitochondrial biogenesis or autophagy by the uncouplers. However, we observed a decrease in the relative amount of fragmented mitochondria. The latter may significantly change the signaling properties of mitochondria. Earlier we showed that both classic and mitochondria-targeted antioxidants inhibited the TNF-induced NFκB-dependent activation of endothelium. The present data suggest that the antiinflammatory effect of mild uncoupling is related to its antioxidant action. PMID:26071781

  16. PHENOLIC CONTENT AND ANTIOXIDANT ACTIVITY OF SUPERCRITICAL CARBON DIOXIDE TREATED AND AIR-CLASSIFIED OAT BRAN CONCENTRATE MICROWAVE-IRRADIATED IN SOLVENTS AT VARYING TEMPERATURES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In addition to health-beneficial beta-glucans, oats contain phenolic compounds (PC) and other antioxidant activity (AA). We investigated processing technologies to produce oat ingredients with concentrated levels of PC and AA. Oat bran concentrate (OBC) had lipids removed by supercritical carbon d...

  17. Upregulation of endothelial heme oxygenase-1 expression through the activation of the JNK pathway by sublethal concentrations of acrolein

    SciTech Connect

    Wu, C.C.; Hsieh, C.W.; Lai, P.H.; Lin, J.B.; Liu, Y.C.; Wung, B.S. . E-mail: bswung@mail.ncyu.edu.tw

    2006-08-01

    Acrolein is a highly electrophilic {alpha},{beta}-unsaturated aldehyde that is present in cigarette smoke. Heme oxygenase-1 (HO-1) is a cytoprotective enzyme activated by various such electrophilic compounds. In this study, the regulatory effects of acrolein upon the expression of HO-1 were investigated in endothelial cells (ECs). We demonstrate that acrolein induces the elevation of HO-1 protein levels, and subsequent enzyme activity, at non-cytotoxic concentrations. An additional {alpha},{beta}-unsaturated aldehyde, cinnamaldehyde, was also found to increase HO-1 expression and have less cytotoxicity than acrolein. Moreover, acrolein-mediated HO-1 induction is abrogated in the presence of actinomycin D and cycloheximide. Nrf2 is a transcription factor involved in the induction of HO-1 through an antioxidant response element (ARE) in the promoter region of the HO-1 gene. We show that acrolein induces Nrf2 translocation and ARE-luciferase reporter activity. Acrolein was also found to induce the production of both superoxide and H{sub 2}O{sub 2} at levels greater than 100 {mu}M. However, with the exception of NAC, no antioxidant generated any effect upon acrolein-dependent HO-1 expression in ECs. Our present findings suggest that reactive oxygen species (ROS) may not be a major modulator for HO-1 induction. Using buthionine sulfoximine to deplete the intracellular GSH levels further enhanced the effects of acrolein. We also found that cellular GSH level was rapidly reduced after both 10 and 100 {mu}M acrolein treatment. However, after 6 h of exposure to ECs, only 10 {mu}M acrolein treatment increases GSH level. In addition, only the JNK inhibitor SP600125 and tyrosine kinase inhibitor genistein had any significant inhibitory impact upon the upregulation of HO-1 by acrolein. Pretreatment with a range of other PI3 kinase inhibitors, including wortmannin and LY294002, showed no effects. Hence, we show in our current experiments that a sublethal concentration of

  18. Effective removal of sulfur components from Brazilian power-coals by ultrasonication (40kHz) in presence of H2O2.

    PubMed

    Saikia, Binoy K; Dalmora, Adilson C; Choudhury, Rahul; Das, Tonkeswar; Taffarel, Silvio R; Silva, Luis F O

    2016-09-01

    The present investigation reports a preliminary attempt of using ultrasonic energy (40kHz) to clean some low rank high sulfur Brazilian power-coal samples in presence of H2O2 solution. All types of sulfur components (i.e. pyritic, sulfate and organic) could be removed from the coal samples by this process. The raw and ultrasonicated coal samples were characterized by chemical analysis, Fourier Transformation Infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), focused ion beam (FIB), high-resolution transmission electron microscope (HR-TEM) with selected area electron diffraction (SAED) and/or microbeam diffraction (MBD), scanning transmission electron microscopy (STEM), energy-dispersive X-ray spectrometer (EDS), and Thermogravimetry (TG-DTG) techniques to evaluate the clean-coal quality. The FT-IR spectroscopic analysis demonstrated the formation of oxidized sulfur species (SO and -SO2) and their subsequent removals after ultrasonication. The XRD profiles supported the presence of mineral matters in the coals. The TG-DTG profiles of the beneficiated coals revealed their improved quality for using in thermal plants with better combustion efficiency. PMID:27150755

  19. Hydrogen peroxide-induced production of a 40 kDa immunoreactive thyroglobulin fragment in human thyroid cells: the onset of thyroid autoimmunity?

    PubMed Central

    Duthoit, C; Estienne, V; Giraud, A; Durand-Gorde, J M; Rasmussen, A K; Feldt-Rasmussen, U; Carayon, P; Ruf, J

    2001-01-01

    We recently reported that, during in vitro thyroid-hormone synthesis, H(2)O(2) stress cleaved thyroglobulin (Tg) into C-terminal peptides. These peptides were found to contain the immunodominant region of Tg recognized by Tg autoantibodies from patients with an autoimmune thyroid disease. To test the hypothesis that Tg fragmentation is an early upstream initiating event involved in Tg autoimmune response and the consequence of oxidative injuries, we studied the effect of H(2)O(2) stress on human thyroid cells. In culture conditions allowing Tg synthesis and iodine organification by the cells, we found that bolus addition of increasing millimolar doses of H(2)O(2) induced a dose-response appearance of floating cells in the culture medium. These cells apparently resulted from a necrotic process, and they bore iodinated Tg fragments. These fragments were found to be similar to those previously obtained in vitro from purified Tg. In both cases, Tg peptides were recognized by a well-defined monoclonal antibody directed to the immunodominant region of Tg. The smallest immunoreactive Tg peptide had a molecular mass of 40 kDa and entered human thyrocytes more efficiently than the entire Tg. These data suggest that thyrocytes exposed to locally increased H(2)O(2) doses accumulate fragmented Tg for further delivery into surrounding living thyrocytes in the course of an autoimmune response. PMID:11736644

  20. Low-cycle fatigue/high-cycle fatigue (LCF/HCF) interaction studies using a 10- to 40-kHz HCF loading device

    NASA Astrophysics Data System (ADS)

    Matikas, Theodore E.

    1999-02-01

    To simulate the testing conditions experienced by aircraft engine turbine blades, a new experimental facility was developed capable of providing interactive low cycle fatigue (LCF)/high cycle fatigue (HCF) loading. The new facility is based on a HCF cell that can operate in the 10-40 kHz frequency range. This HCF testing cell can also be interfaced to a servo-hydraulic load frame, which provides a second fatigue cycle. Sample geometry is critical for the HCF cell to produce the desired applied load on the specimen. The objective of this research is to develop analytical modeling necessary for the design of test coupons to be used in the new HCF testing cell operating at ultrasonic frequencies, and also to demonstrate the capabilities of the new device by performing LCF/HCF interaction studies in Ti-6Al-4V. The results of these studies clearly showed the effect of the HCF component of the load in spite the fact that the HCF component was only 15-19 percent of the overall load. It was also found that the HCF component of the load was the major cause of observed damage with the LCF component having much less effect. Eliminating the HCF component completely resulted in increasing the fatigue life at least an order of magnitude.

  1. Tracing of ca 800 yr old mining activity in peat bog using Pb elemental concentrations and isotope compositions.

    NASA Astrophysics Data System (ADS)

    Baron, S.; Carignan, J.; Ploquin, A.

    2003-04-01

    Sixty sites of slags have been documented on the Mont-Lozère in southern France. The petrographic analysis shows that slags are metallurgical wastes (800 to 850 yr BP) which certainly result from smelting activity for lead and silver extraction (Ploquin et al., 2001). The aims of this study are: 1) to trace the source of Pb ores which supplied the smelting sites, by using the Pb isotopic composition of several surrounding Pb deposits, 2) to evaluate the actual pollution caused by these slags, by using elemental and isotopic compositions of soils, water and vegetation, and 3) to document the pollution history of the region, by using elemental and isotopic compositions of peat bog cores collected in the neighbourhood of the historical smelting sites. The lead isotopic composition of galena collected in most surrounding ores is very similar to that of different slag samples. On the other hand, the high precision of the results allowed us to select the mineralised areas which were probably the ore sources. The Pb isotopic composition of slags is even more homogeneous: 208/206 Pb: 2.092±0.002; 206/207 Pb: 1.179±0.001; 208/204 Pb: 38.663±0.025; 207/204 Pb: 15.665±0.006; 206/204 Pb: 18.476±0.023, and will allow source tracing in the environment. The "Narses Mortes" peat bog, around which two smelting sites have been reported, is strongly minerotrophic and contains 8 to 60% ash. A 1.40 m core have been retrieved and divided into 58 individual samples. Minerotrophic peat bog records both atmospheric deposition, soils leaching and the grounwater influence. The measured metal concentrations are normalised to Al contents of peat bog samples and the metal/Al ratios are compared to that of the Mont-Lozère granite: relative excess in metal concentrations are found in peat bog samples. An increasing excess of most metals (Pb, Zn, Cd...) was measured for surface samples, from 55 cm depth to the top of the core (23 cm depth). This profil might be attributed to atmospheric

  2. Concentration of thymidine kinase 1 in serum (S-TK1) is a more sensitive proliferation marker in human solid tumors than its activity.

    PubMed

    He, Qimin; Zhang, Pinggn; Zou, Li; Li, Hongxun; Wang, Xiuqin; Zhou, Shan; Fornander, Tommy; Skog, Sven

    2005-10-01

    Activity of thymidine kinase 1 in serum (STK) is a useful marker for leukaemia and lymphoma, but not for solid tumors. We investigate thymidine kinase 1 concentration in serum (S-TK1) as a potential tumor marker. S-TK1 concentration and STK activity levels were determined in 9 human malignant diseases (breast, gastric, rectal, colorectal, lung, brain cancer, hepatoma, lymphoma, leukaemia) and in benign and non-cancerous diseases, representing 850 preoperative cases. Healthy volunteers (n=43) were used as positive controls. S-TK1 concentration was determined by ECL dot blot assay and STK activity levels by an RIA assay. S-TK1 concentrations and STK activity levels in preoperative malignant patients were significantly higher than in healthy individuals, in patients with benign tumors and in those with non-cancerous diseases. Significant correlations between concentration and activity level were only found in healthy individuals, in patients with benign tumors, and in some patients with malignancies, i.e. leukaemia, and breast and gastric cancers. About 90-95 percent of the malignant patients showed S-TK1 concentrations above those of the healthy controls. The corresponding value for STK activity was about 75 percent. When sera from malignant patients were diluted with sera from healthy individuals, S-TK1 concentrations and STK activity levels decreased more than expected. This indicates the presence of a compound (or compounds) in the serum of healthy individuals that destabilises S-TK1. We conclude that S-TK1 concentration is a more sensitive tumor marker in solid malignancies than is STK activity. PMID:16142366

  3. Short-term variations of methane concentrations and methanotrophic activity in a coastal inlet (Eckernförde Bay, Germany)

    NASA Astrophysics Data System (ADS)

    Niemann, Helge; Richner, Dominik; Steinle, Lea; Schneider von Deimling, Jens; Urban, Peter; Hoffmann, Jasper; Schmidt, Mark; Treude, Tina; Lehmann, Moritz F.

    2015-04-01

    Large quantities of the greenhouse gas methane are produced in anoxic sediments of continental margins and may be liberated into the overlying water column and, potentially, into the atmosphere where it further contributes to global warming. However, a sequence of microbially mediated methane oxidation pathways in sediments and the water column mitigate the contribution of oceans to the atmospheric methane budget. In anoxic sediments, specialised archaea oxidise methane with sulphate in a process that has been termed the anaerobic oxidation of methane (AOM). In addition, aerobic bacteria at the sediment surface and the water column have the potential to consume methane (aerobic oxidation of methane; MOx) that has by passed the benthic, microbial filter. However methane cycling in (aerobic) marine waters is not well constrained. Particularly little is known about spatiotemporal aspects of MOx activity and the underlying key physical, chemical and biological factors. Here we show results from our investigations on methane dynamics on very short time scales of hours to days in the Eckernförde Bay (E-Bay), a costal inlet of the Baltic Sea in northern Germany featuring seasonal bottom water hypoxia/anoxia. In autumn 2014, we observed high spatiotemporal variations in water column methane contents and MOx activity: Anoxic bottom waters in a trough in the northern part of the bay contained extremely high methane concentrations of up to 800 nM, which sharply declined at the midwater redox interface (though methane remained supersaturated with respect to the atmospheric equilibrium throughout the water column at all times). The methane decrease at the redox interface was related to highly active MOx communities consuming methane under microoxic conditions at rates of up 40 nM/d. About 12 hours later, the methane content and the extent of bottom water anoxia was much lower and MOx activity was highly reduced in the northern part but strongly elevated in the southern part of

  4. Short-term variations of methane concentrations and methanotrophic activity in a coastal inlet (Eckernförde Bay, Germany)

    NASA Astrophysics Data System (ADS)

    Richner, Dominik; Niemann, Helge; Steinle, Lea; Schneider von Deimling, Jens; Urban, Peter; Hoffmann, Jasper; Schmidt, Mark; Treude, Tina; Lehmann, Moritz

    2016-04-01

    Large quantities of methane are produced in anoxic sediments of continental margins and may be liberated into the overlying water column and, potentially, into the atmosphere. However, a sequence of microbially mediated methane oxidation pathways in sediments and the water column mitigate the contribution of oceans to the atmospheric methane budget. Of particular importance are methanotrophic bacteria in the water column that mediate the aerobic oxidation of methane (MOx), and represent the final sink for methane before its release to the atmosphere where it acts as a potent greenhouse gas. However methane cycling in (aerobic) marine waters is not well constrained. Particularly little is known about spatiotemporal aspects of MOx activity and the underlying key physical, chemical and biological factors. Here we show results from our investigations on methane dynamics on very short time scales of hours to days in the Eckernförde Bay (E-Bay), a costal inlet of the Baltic Sea in northern Germany featuring seasonal bottom water hypoxia/anoxia. In autumn 2014, we observed highly spatiotemporal variations in water column methane contents and MOx activity: Anoxic bottom waters in a trough in the northern part of the bay contained extremely high methane concentrations of up to 800 nM, which sharply declined at the midwater redox interface (methane remained supersaturated with respect to the atmospheric equilibrium throughout the water column at all times). The methane decrease at the redox interface was related to highly active MOx communities consuming methane under microoxic conditions at rates of up 40 nM/d. About 12 hours later, the methane content and the extend of bottom water anoxia was much lower and MOx activity was highly reduced in the northern part but strongly elevated in the southern part of the bay. A few days later, bottom water anoxia, methane loading and MOx activity was partially re-established. In this contribution, we will discuss potential forcing

  5. Seasonal and spatial variations of 210Po and 210Pb activity concentrations in Mytilus galloprovincialis from Croatian coast of the Adriatic Sea.

    PubMed

    Rožmarić, Martina; Rogić, Matea; Benedik, Ljudmila; Štrok, Marko; Barišić, Delko

    2013-11-01

    Results of 2 years monitoring of (210)Po and (210)Pb activity concentrations in soft tissue of the species Mytilus galloprovincialis from Croatian part of the Adriatic coast are presented. The samples were collected at thirteen coastal stations (some of which are also a part of the Mediterranean Mussel Watch Project) in spring and autumn of 2010 and 2011. The collected mussels were ranging between 4 cm and 6 cm in shell length. After sample pre-treatment lead and polonium were radiochemically separated on Sr resin. (210)Po was determined by alpha-particle spectrometry and (210)Pb was determined, via (210)Bi, by a low-level gas proportional counter. The results of (210)Po activity concentrations were found to vary between (104±11) and (1421±81) Bq kg(-1) dry weight while (210)Pb activity concentrations were much lower and in range (8.2±5.3)-(94.1±29.8) Bq kg(-1) dry weight. Higher (210)Po and (210)Pb activity concentrations were determined in spring period. The inter-site differences seen in their activity concentrations can be due to natural background levels of sites. The (210)Po/(210)Pb activity concentration ratios in all cases exceeded unity for all mussel samples and ranged between 4.0 and 47.9. PMID:23932819

  6. Direct observation of solid-phase adsorbate concentration profile in powdered activated carbon particle to elucidate mechanism of high adsorption capacity on super-powdered activated carbon.

    PubMed

    Ando, Naoya; Matsui, Yoshihiko; Matsushita, Taku; Ohno, Koichi

    2011-01-01

    Decreasing the particle size of powdered activated carbon (PAC) by pulverization increases its adsorption capacities for natural organic matter (NOM) and polystyrene sulfonate (PSS, which is used as a model adsorbate). A shell adsorption mechanism in which NOM and PSS molecules do not completely penetrate the adsorbent particle and instead preferentially adsorb near the outer surface of the particle has been proposed as an explanation for this adsorption capacity increase. In this report, we present direct evidence to support the shell adsorption mechanism. PAC particles containing adsorbed PSS were sectioned with a focused ion beam, and the solid-phase PSS concentration profiles of the particle cross-sections were directly observed by means of field emission-scanning electron microscopy/energy-dispersive X-ray spectrometry (FE-SEM/EDXS). X-ray emission from sulfur, an index of PSS concentration, was higher in the shell region than in the inner region of the particles. The X-ray emission profile observed by EDXS did not agree completely with the solid-phase PSS concentration profile predicted by shell adsorption model analysis of the PSS isotherm data, but the observed and predicted profiles were not inconsistent when the analytical errors were considered. These EDXS results provide the first direct evidence that PSS is adsorbed mainly in the vicinity of the external surface of the PAC particles, and thus the results support the proposition that the increase in NOM and PSS adsorption capacity with decreasing particle size is due to the increase in external surface area on which the molecules can be adsorbed. PMID:20851447

  7. Miltefosine Increases Lipid and Protein Dynamics in Leishmania amazonensis Membranes at Concentrations Similar to Those Needed for Cytotoxicity Activity

    PubMed Central

    Moreira, Rodrigo Alves; Mendanha, Sebastião Antonio; Fernandes, Kelly Souza; Matos, Grazzielle Guimaraes; Alonso, Lais; Dorta, Miriam Leandro

    2014-01-01

    Miltefosine (MT) is a membrane-active alkylphospholipid licensed for the topical treatment of breast cancer skin metastases and the oral treatment of leishmaniasis, although its mechanism of action remains unclear. Electron paramagnetic resonance (EPR) spectroscopy of a spin-labeled lipid and a thiol-specific spin label in the plasma membrane of Leishmania promastigotes showed that MT causes dramatic increases in membrane dynamics. Although these alterations can be detected using a spin-labeled lipid, our experimental results indicated that MT interacts predominantly with the protein component of the membrane. Cell lysis was also detected by analyzing the supernatants of centrifuged samples for the presence of spin-labeled membrane fragments and cytoplasmic proteins. Using a method for the rapid incorporation of MT into the membrane, these effects were measured immediately after treatment under the same range of MT concentrations that cause cell growth inhibition. Cytotoxicity, estimated via microscopic counting of living and dead cells, indicated ∼70% cell death at the concentration of MT at which EPR spectroscopy detected a significant change in membrane dynamics. After this initial impact on the number of viable parasites, the processes of cell death and growth continued during the first 4 h of incubation. The EPR spectra of spin-labeled membrane-bound proteins were consistent with more expanded and solvent-exposed protein conformations, suggesting a detergent-like action. Thus, MT may form micelle-like structures around polypeptide chains, and proteins with a higher hydrophobicity may induce the penetration of hydrophilic groups of MT into the membrane, causing its rupture. PMID:24614380

  8. Measurement of natural radioactive nuclide concentrations in various metal ores used as industrial raw materials in Japan and estimation of dose received by workers handling them.

    PubMed

    Iwaoka, Kazuki; Tagami, Keiko; Yonehara, Hidenori

    2009-11-01

    Natural resources such as ores and rocks contain natural radioactive nuclides at various concentrations. If these resources contain high concentrations of natural radioactive nuclides, workers handling them might be exposed to significant levels of radiation. Therefore, it is important to investigate the radioactive activity in these resources. In this study, concentrations of radioactive nuclides in Th, Zr, Ti, Mo, Mn, Al, W, Zn, V, and Cr ores used as industrial raw materials in Japan were investigated. The concentrations of (238)U and (232)Th were determined by inductively coupled plasma mass spectrometry (ICP-MS), while those of (226)Ra, (228)Ra, and (40)K were determined by gamma-ray spectrum. We found the concentrations of (238)U series, (232)Th series, and (40)K in Ti, Mo, Mn, Al, W, Zn, V, and Cr ores to be lower than the critical values defined by regulatory requirements as described in the International Atomic Energy Agency (IAEA) Safety Guide. The doses received by workers handling these materials were estimated by using methods for dose assessment given in a report by the European Commission. In transport, indoor storage, and outdoor storage scenarios, an effective dose due to the use of Th ore was above 4.3 x 10(-2)Sv y(-1), which was higher than that of the other ores. The maximum value of effective doses for other ores was estimated to be about 4.5 x 10(-4)Sv y(-1), which was lower than intervention exemption levels (1.0 x 10(-3)Sv y(-1)) given in International Commission of Radiological Protection (ICRP) Publication 82. PMID:19703725

  9. Relative reactivity of ribosyl 2'-OH vs. 3'-OH in concentrated aqueous solutions of phosphoimidazolide activated nucleotides

    NASA Technical Reports Server (NTRS)

    Kanavarioti, A.; Lee, L. F.; Gangopadhyay, S.

    1999-01-01

    Phosphoimidazolide activated ribomononucleotides (*pN, see structure) are useful substrates for the non-enzymatic synthesis of oligonucleotides. In the presence of metal ions, aqueous solutions of *pN yield primarily the two internucleotide-linked (pN2' pN and pN3' pN) and the pyrophosphate-linked (N5' ppN) dimers. Small amounts of cyclic dimers and higher oligomers are also produced. In this study the relative reactivity of 2'-OH vs. 3'-OH was determined from the ratio of the yields of pN2' pN vs. pN3' pN. Experiments were performed at 23 degrees C in the range 7.2 < or = pH < or = 8.4 with substrates that differ in nucleobase (guanosine (G), cytidine (C), uridine (U), and adenosine (A)) and leaving group (imidazole (Im), 2-methylimidazole (2-MeIm) and 2,4-dimethylimidazole (2,4-diMeIm)). Two metal ions (Mg2+ or Mn2+) were employed as catalysts. The conditions used here, i.e. a substrate concentration in the range 0.1 M to 1.0 M and metal ion concentration in the range 0.05 M to 0.2 M, favor base-stacking interactions. The ratio pN2' pN: pN3' pN = 2'-5': 3'-5' was found independent of nucleobase and typically varied between 2 to 3 indicating that the 2'-OH is about 2 to 3 times more reactive than the 3'-OH. *pN with Im, compared to 2-MeIm and 2,4-diMeIm leaving group, produce lower yields of internucleotide linked dimers, and a higher pN2' pN: pN3' pN ratio. Trends in the data, observed with all three leaving groups, suggest an increase in pN2' pN: pN3' pN ratio with decreasing substrate concentration (up to 5.47 with 0.051 M ImpG). The observations are in accord with earlier studies reporting a relative reactivity 2'-5': 3'-5' = 6 to 9 obtained with Im as the leaving group, in dilute nucleotide solutions and under conditions that disfavor stacking. It is speculated that the concentration induced change in the relative reactivity is the result of self-association via base-stacking that enhances selectively the proximity of the 3'-OH of one molecule to the reactive

  10. Im10A, a short conopeptide isolated from Conus imperialis and possesses two highly concentrated disulfide bridges and analgesic activity.

    PubMed

    Yu, Shuo; Du, Tianpeng; Liu, Zhuguo; Wu, Qiaoling; Feng, Guixue; Dong, Mingxin; Zhou, Xiaowei; Jiang, Ling; Dai, Qiuyun

    2016-07-01

    In the present study, we isolated, synthesized and NMR structurally characterized a novel conopeptide Im10A consisting of 11 amino acids (NTICCEGCMCY-NH2) from Conus imperialis. Unlike other conopeptides with four cysteine residues, Im10A had only two residues in loop 1 and one residue in loop 2 (CC-loop1-C-loop2-C), which formed a stable disulfide connectivity "I-IV, II- III" (framework X) with a type I β-turn. Interestingly, Im10A exhibited 50.7% analgesic activity on rat partial sciatic nerve ligation (PNL) at 2h after Im10A administration. However, 10μM Im10A exhibited no apparent effect on neuronal nicotinic acetylcholine receptor, and it did not target DRG voltage-dependent sodium, potassium and calcium ion channels and opioid receptor. To our knowledge, Im10A had the most concentrated disulfide bridges among conopeptides with four cysteine residues. This finding provided a new motif for the future development of biomimetic compounds. PMID:27131596

  11. Efficacy of viral clearance methods used in the manufacture of activated prothrombin complex concentrates: focus on AUTOPLEX T.

    PubMed

    Horwith, G; Revie, D R

    1999-09-01

    Various methods are described for the elimination of infectious viruses from activated prothrombin complex concentrates (aPCCs) and for the analysis of the final products (AUTOPLEX T and FEIBA VH). Viruses of concern in human plasma-derived products are enveloped (hepatitis B and C, cytomegalovirus, Epstein-Barr virus, and human immunodeficiency virus [HIV]) and nonenveloped (hepatitis A and parvovirus B19). Donated blood used for AUTOPLEX T is screened for antihepatitis C, HBsAg, anti-HIV types 1 and 2, and p24 antigen. Plasma pools utilized for raw materials are also tested by PCR for HIV and hepatitis C virus. Partial virus inactivation and partitioning are achieved by purification of the aPCC. Further reduction of virus infectivity is accomplished by lyophilization and dry-heat treatment. Each step undergoes virus elimination validation studies in which a relevant sample is 'spiked' with the appropriate virus or model virus. The total reduction in virus from raw material to final product can then be calculated. For AUTOPLEX T the cumulative log10 reduction factors for several viruses vary from 4.2 to 14.3. This ensures an exceptionally high margin of safety. Definitive evidence for product safety was obtained by clinical observation of treated patients. The viral inactivation process of AUTOPLEX T involves a four-tier viral safety program, including Cohn alcohol fractionation and dry-heat treatment, in place of the two-stage vapour-heating process for FEIBA. PMID:10597384

  12. Anthocyanins and their gut metabolites reduce the adhesion of monocyte to TNFα-activated endothelial cells at physiologically relevant concentrations.

    PubMed

    Krga, Irena; Monfoulet, Laurent-Emmanuel; Konic-Ristic, Aleksandra; Mercier, Sylvie; Glibetic, Maria; Morand, Christine; Milenkovic, Dragan

    2016-06-01

    An increasing number of evidence suggests a protective role of dietary anthocyanins against cardiovascular diseases. Anthocyanins' extensive metabolism indicates that their metabolites could be responsible for the protective effects associated with consumption of anthocyanin-rich foods. The aim of this work was to investigate the effect of plasma anthocyanins and their metabolites on the adhesion of monocytes to TNFα-activated endothelial cells and on the expression of genes encoding cell adhesion molecules. Human umbilical vein endothelial cells (HUVECs) were exposed to circulating anthocyanins: cyanidin-3-arabinoside, cyanidin-3-galactoside, cyanidin-3-glucoside, delphinidin-3-glucoside, peonidin-3-glucoside, anthocyanin degradation product: 4-hydroxybenzaldehyde, or to their gut metabolites: protocatechuic, vanillic, ferulic and hippuric acid, at physiologically-relevant concentrations (0.1-2 μM) and time of exposure. Both anthocyanins and gut metabolites decreased the adhesion of monocytes to HUVECs, with a magnitude ranging from 18.1% to 47%. The mixture of anthocyanins and that of gut metabolites also reduced monocyte adhesion. However, no significant effect on the expression of genes encoding E-selectin, ICAM1 and VCAM1 was observed, suggesting that other molecular targets are involved in the observed effect. In conclusion, this study showed the potency of anthocyanins and their gut metabolites to modulate the adhesion of monocytes to endothelial cells, the initial step in atherosclerosis development, under physiologically-relevant conditions. PMID:26873533

  13. Treatment of Platelet Concentrates with the Mirasol Pathogen Inactivation System Modulates Platelet Oxidative Stress and NF-κB Activation

    PubMed Central

    Johnson, Lacey; Marks, Denese

    2015-01-01

    Background Pathogen inactivation (PI) technologies for platelets aim to improve transfusion safety by preventing the replication of contaminating pathogens. However, as a consequence of treatment, aspects of the platelet storage lesion are amplified. Mirasol treatment also affects platelet signal transduction and apoptotic protein expression. The aim of this study was to examine the effect of Mirasol treatment on the generation of reactive oxygen species (ROS) and subsequent oxidative stress. Methods Pooled platelet concentrates were prepared in platelet-additive solution (70% SSP+ / 30% plasma). ABO-matched platelets were pooled and split, and treated with the Mirasol system (TerumoBCT) or left untreated as a control. Platelet samples were tested on day 1, 5, and 7 post-collection. Results Mirasol-treated platelets had increased formation of ROS by day 5 of storage. Oxidative damage, in the form of protein carbonylation, was higher in Mirasol-treated platelets, whilst no effect on nitrotyrosine formation or lipid peroxidation was detected. The NF-κB signaling pathway was also activated in Mirasol-treated platelets, with increased expression and phosphorylation of NF-κB p65 and IκBα. Conclusion These data demonstrate that Mirasol-treated platelets produce more ROS and display protein alterations consistent with oxidative damage. PMID:26195930

  14. Effects of concentration and thermal annealing on the optical activation of Er implanted into GaN layers

    NASA Astrophysics Data System (ADS)

    Sathish, N.; Pathak, A. P.; Devaraju, G.; Trave, E.; Mazzoldi, P.; Dhamodaran, S.; Kulkarni, V. N.

    2012-07-01

    The wide band gap semiconductor, GaN, has emerged as an important host for rare earth-electroluminescence. The annealing behaviour and lattice site location of Er implanted into GaN were studied with the Rutherford Backscattering Spectrometry (RBS)/channelling and photoluminescence (PL) techniques. Also Er site dependence on the annealing temperature and implantation dose has been studied in detail. The optical properties of the Er-doped GaN system, evidencing their dependence on the parameters adopted during the synthesis procedure (Er implantation dose, annealing temperature) have been discussed. RBS/channelling measurements suggested that mostly Er occupy substitutional site and depends on the Er concentration. The main result is the activation of a typical Er giving rise to PL emission in the 1450-1650 nm range, related to radiative 4 I 13/2→4 I 15/2 transitions. Depending on the Er dose, we observe a specific behaviour linked to variation of the annealing temperature that strongly determines PL emission band. We observed a PL spectral shape with the main peak located at 1542 nm and shoulder peak at 1558 nm (and full width at half maximum (FWHM) of 33 nm) with a series of weaker PL structures at 1519, 1572 and 1591 nm, due to the Stark sub-level splitting.

  15. Circulating interleukin-1β and interleukin-6 concentrations are closely associated with γ-glutamyltranspeptidase activity in middle-aged Japanese men without obvious cardiovascular diseases.

    PubMed

    Mochizuki, Kazuki; Misaki, Yasumi; Miyauchi, Rie; Takabe, Satsuki; Shimada, Masaya; Miyoshi, Noriyuki; Ichikawa, Yoko; Goda, Toshinao

    2011-07-01

    Interleukin (IL)-1β and IL-6 expressions are known to be induced by oxidant stress. In the present study, we examined the relationships between these interleukins and the activity of γ-glutamyltranspeptidase (γ-GTP), which was recently reported as a source of oxidant stress production, in the circulating blood of middle-aged Japanese men without obvious cardiovascular diseases. We conducted a cross-sectional study of 317 Japanese men without obvious cardiovascular diseases aged 40 to 69 years (mean ± SD, 58.6 ± 7.6 years) who participated in health checkups in Japan. We analyzed their clinical parameters in serum, lifestyle factors, and plasma IL-1β and IL-6 concentrations. We compared the relationships between these interleukin concentrations and the clinical parameters and lifestyle factors by Spearman correlation coefficients. Stepwise multiple linear regression analyses for interleukins based on the other parameters and γ-GTP, which were classified into 3 groups according to the concentrations, were performed. Interleukin-1β and IL-6 concentrations were closely associated with γ-GTP activity but less associated with alanine aminotransferase and aspartate aminotransferase activities by Spearman correlation coefficients. Stepwise multiple linear regression analyses showed that γ-GTP activity was the explanatory variable for elevated IL-1β and IL-6 concentrations. As natural logarithms, the IL-1β and IL-6 concentrations were estimated to be 1.734- and 1.157-fold higher, respectively, in subjects with high γ-GTP activity ranges than in subjects with a low γ-GTP activity range. The present results show that circulating IL-1β and IL-6 concentrations are strongly and independently associated with γ-GTP activity in middle-aged Japanese men without obvious cardiovascular diseases. PMID:20934730

  16. Influence of age and composition of shelterbelts plants on enzyme activity and auxine - phytophormone IAA concentrations in soils

    NASA Astrophysics Data System (ADS)

    Wojciech Szajdak, Lech; Gaca, Wioletta; Meysner, Teresa; Styła, Katarzyna; Maryganova, Victoria

    2010-05-01

    The investigations were carried out in Dezydery Chlapowski Agroecological Landscape Park in Turew (40 km South-West of Poznań, West Polish Lowlands, 16° 45 E and 52° 01 N). The soil samples were taken from two shelterbelts differing the age and the composition of trees. First 200-years-old shelterbelt is consisting mainly by Robinia pseudacacia and small admixture of Quercus robur and Larix deciduas. It has 2 kilometers of length and 36 meters of width. The second one new shelterbelt (many species) was created in 1993 and consists of several species of plants such as: Quercus pertraea and Quercus robur, Larix decidua, Pinus silvestris, Sorbus aucuparia, Sorbus intermedia and Tilia cordata. Its length is 340 meters and its width is 17.5 meters. All shelterbelts and adjoining cultivated fields were introduced on Hapludalfs soils (according to FAO classification). In soil under two shelterbelts and adjoining cultivated fields the activity of the following enzymes nitrate reductase, urease, xanthine oxidase, phenol oxidase, peroxidase activity were measured. In addition, the concentrations of iron ions, indole-3-acetic acids, total organic carbon, dissolved organic carbon, total nitrogen, ammonium and nitrates were determined. In soils under shelterbelts compared to adjoining cultivated fields higher content of organic matter was observed, because the accumulation of soil organic matter under shelterbelts is suggested to be the main mechanism of long-term withdrawal of various chemical elements from cycling in the agroecosystems. However, many chemical, biochemical, physical and biological processes control conversions of organic compounds in soils and finally these processes depend on the organic matter content and particularly on humic substances. Due to a very good developed root system of trees in shelterbelts than cultivated plants, they transpire more than 34% water than cultivated fields and intensively take up nutrients and finally improve quality of ground

  17. Concentrator Systems

    NASA Astrophysics Data System (ADS)

    Luque-Heredia, Ignacio; Luque, Antonio

    2015-10-01

    The following sections are included: * Introduction * The early development of CPV * Concentrator solar cells * Optics for photovoltaic concentrators * Photovoltaic concentration modules * Tracking systems for photovoltaic concentration * High-concentration systems * Rating and performance * Cost considerations * Conclusions * References

  18. Effects of the monoclonal antibody against porcine 40 kDa adipocyte-specific plasma membrane protein on adipocytes and carcass composition.

    PubMed

    Gao, Shizheng; Ge, Changrong; Zhang, Xi; Liu, Yonggang

    2007-07-01

    The effects of the mouse monoclonal antibody against 40 kDa adipocyte-specific plasma membrane protein on porcine adipocytes and carcass composition were investigated in vitro and in vivo. Results revealed that the in vitro complement-mediated cytotoxicity of this monoclonal antibody can lead to adipocyte lysis, remarkable reduction of adipocyte lipid accumulation (P<0.01), and significant decrease of well-differentiated fat cells (P<0.01). Treatment of adipocytes with this antibody alone in vitro did not induce cell lysis, but could lead to noticeable reduction of well-differentiated cells and lipid accumulation (P<0.05) at the pre-adipocyte stage. In vivo, pigs injected with 0.5 mg/kg or 1.0 mg/kg of antibody showed smaller adipocyte sizes (P<0.01) and reduced lipid accumulation of adipocytes (P<0.01). Our results also indicated that pigs intraperitoneally or subcutaneously immunized with 0.5 mg/kg of monoclonal antibody at 15 kg or 1.0 mg/kg antibody at 60 kg had a higher lean meat percentage (P<0.05), larger loin eye area (P<0.05), lower fat meat percentage (P<0.05), less backfat thickness (P<0.05) and smaller leaf fat weight (P<0.05) than the control pigs, but other carcass traits such as caul fat weight, heart weight, liver weight, spleen weight, kidney weight, lung weight, and dressing percentage were not significantly affected. These results suggested that this monoclonal antibody could be applied to restrain excessive fat deposition in porcine production. PMID:17622468

  19. Effects of lemakalim on changes in Ca2+ concentration and mechanical activity induced by noradrenaline in the rabbit mesenteric artery.

    PubMed Central

    Ito, S.; Kajikuri, J.; Itoh, T.; Kuriyama, H.

    1991-01-01

    1. Effects of (-)-cromakalim (lemakalim) on tension and Ca2+ mobilization induced by noradrenaline (NA) were investigated by measuring intracellular Ca2+ concentration ([Ca2+]i) isometric tension and production of inositol-1,4,5-trisphosphate (IP3) in smooth muscle strips of the rabbit mesenteric artery. 2. In thin smooth muscle strips, 10 microM NA produced a large phasic, followed by a small tonic increase in [Ca2+]i, which correlated well with the evoked phasic and tonic contractions, respectively. Lemakalim (0.1-10 microM) lowered the resting [Ca2+]i without a decrease in the resting tension, and also inhibited the increased [Ca2+]i and tension induced by 10 microM NA, all in a concentration-dependent manner. Glibenclamide (1 microM) inhibited these actions of lemakalim. 3. In Ca(2+)-free solution containing 2 mM EGTA, NA (10 microM) transiently increased [Ca2+]i, tension and synthesis of IP3. Lemakalim (over 0.01 microM) inhibited these actions of NA in Ca(2+)-free solution containing 5.9 mM K+, but not in Ca(2+)-free solution containing 128 mM K+. These actions of lemakalim were prevented by glibenclamide (1 microM). Lemakalim (1 microM) did not modify the increases in [Ca2+]i and tension induced by 10 mM caffeine. 4. In beta-escin-skinned strips, 10 microM NA increased [Ca2+]i in Ca(2+)-free solution containing 50 microM EGTA, 3 microM guanosine triphosphate (GTP) and 2 microM Fura 2 after the storage sites were loaded by application of 0.3 microM Ca2+ for 2 min, suggesting that Ca2+ is released from intracellular storage sites following activation of the alpha-adrenoceptor. Lemakalim (1 microM) did not inhibit the Ca2+ release from storage sites induced by NA.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1786512

  20. Effect of salinity on hemolymph osmotic pressure, sodium concentration and Na+-K+-ATPase activity of gill of Chinese crab, Eriocheir sinensis

    NASA Astrophysics Data System (ADS)

    Liu, Hongyu; Pan, Luqing; Fu, Lü

    2008-02-01

    The effects of salinity on hemolymph osmotic pressure, Na+ concentration and Na+-K+-ATPase activity of gill of Chinese crab Eriocheir sinensis were studied. The results showed that hemolymph osmotic pressure and Na+ concentration increased significantly ( P<0.05), and the Na+-K+-ATPase activity of gills decreased significantly ( P<0.05) when salinity increased from 0 to 16. The hemolymph osmotic pressure and Na+ concentration in each treatment group rose remarkably at 0.125 d or 0.25 d, while the Na+-K+-ATPase activity of gill reduced gradually with increased experiment time in 3 d. Then the three parameters remained at a constant level after 0.25 d, 0.125 d and 3 d, respectively, and higher hemolymph osmotic pressure, higher Na+ concentration and lower Na+-K+-ATPase activity of gill occurred at higher salinity. The effect of salinity change on protein concentration of hemolymph was indistinct ( P>0.05); However, the protein concentration decreased gradually with the increase of salinity from 0.25 d to 1 d, and then tended to be stable from day 1 to day 15.

  1. Monitoring the concentrations of nonsteroidal anti-inflammatory drugs and cyclooxygenase-inhibiting activities in the surface waters of the Tone Canal and Edo River Basin.

    PubMed

    Nishi, Iwaki; Kawakami, Tsuyoshi; Onodera, Sukeo

    2015-01-01

    Environmental pollution by pharmaceuticals has become a major problem in many countries worldwide. However, little is known about the concentrations of pharmaceuticals in water sources in Japan. The objective of this study was to clarify variations in the concentrations of seven nonsteroidal anti-inflammatory drugs (NSAIDs) and in cyclooxygenase(COX)-inhibiting activities in river water and domestic wastewater collected from the Tone Canal and the Edo River Basin in Japan. Total NSAID concentrations were higher in the Tone Canal than in the Edo River, and the highest concentration was observed at the domestic wastewater inflow point located in the Tone Canal (concentration averages of salicylic acid, ibuprofen, felbinac, naproxen, mefenamic acid, diclofenac, and ketoprofen in wastewater samples were 55.3, 162.9, 39.7, 11.8, 30.8, 259.7, and 48.3 ng L(-1), respectively). Gas chromatography-tandem mass spectrometry showed that wastewater samples collected during cooler seasons contained higher levels of COX-inhibiting activity. COX-inhibiting activities were highly correlated with NSAID concentrations (particularly for ketoprofen and diclofenac); however, other COX inhibitors, such as NSAIDs that were not examined in this study and/or other chemicals with COX-inhibiting activity, could exist in the water samples because the concentrations of NSAIDs obtained from the water samples did not account for the total COX-inhibiting activities observed. Therefore, COX inhibition assays may be helpful for evaluating the aquatic toxicity of COX inhibitors. In this study, we demonstrated that COX inhibitors in surface water may influence aquatic organisms more than was expected based on NSAID concentrations. Thus, further studies examining other COX inhibitors in the aquatic environment are necessary. PMID:26191985

  2. Consequences of diatom mat erosion for carbohydrate concentrations and heterotrophic bacterial activities in intertidal sediments of the Ems-Dollard estuary

    NASA Astrophysics Data System (ADS)

    van Duyl, Fleur C.; Winder, Ben de; Kop, Arjen J.; Wollenzien, Ute

    2000-07-01

    Patches with a diatom mat were compared with adjacent eroded patches on an intertidal flat in the Ems-Dollard estuary. Distinction between patches was made on the basis of chlorophyll- a (chl- a) concentration and relief. Short-term variations and depth distribution were investigated for carbohydrates (water-soluble and water-insoluble carbohydrates), β-glucosidase activity and heterotrophic bacterial production and abundance. The major differences between mat patches and eroded patches were confined to the upper 6 mm. From 6 to 20 mm depth variables in mat patches and eroded patches were roughly comparable, with the exception of the bacterial abundance and β-glucosidase activity. Distinct increases in carbohydrates, bacterial production and abundance during tidal flat exposure were most pronounced in the mat surface layer, but were still detectable in the eroded patches for the different carbohydrate fractions. Concentrations of water-soluble carbohydrates were substantially higher in mats than in eroded patches. This concurred with a much higher bacterial production and abundance in mats than in eroded patches. The β-glucosidase activity in the mat surface was low compared to this activity in eroded patches. In diatom mats, β-glucosidase showed highest activities between 6 and 12 mm, while in eroded patches this maximum occurred at 0-2 mm. Patterns suggest inhibition of the β-glucosidase activity at high concentrations of water-soluble carbohydrate concentrations and a release of inhibition with declining carbohydrate concentrations. Interestingly, concentrations of water-insoluble carbohydrates (EDTA-extracted carbohydrates) did neither clearly differ between mat patches and eroded patches, nor changed substantially with depth. The observation that water-insoluble carbohydrate-to-chl- a ratios were higher outside the mat layer than in the mat, which has a larger stability than eroded patches, indicates that it is a poor index for sediment erodibility. The

  3. Nutritional value of meat: the influence of nutrition and physical activity on vitamin B12 concentrations in ruminant tissues.

    PubMed

    Ortigues-Marty, Isabelle; Micol, Didier; Prache, Sophie; Dozias, Dominique; Girard, Christiane L

    2005-01-01

    An important nutritional characteristic of ruminant meat is its high content in vitamin B12. The variability of these contents is not known. Three studies were been set up in order to test the influence of the animal species (2 studies on Charolais steers slaughtered at 30-32 months of age, n = 24 and n = 30 and a third one on lambs slaughtered at 4.5 months of age, n = 21), of the nature of the diet (grass vs. maize silage, lucerne or concentrate diets) and of physical activity (without or with walking) on the vitamin B12 contents of different muscle types (rather oxidative (Rectus Abdominis, RA), intermediate (Longissimus Dorsi, LD), or glycolytic (Semi Tendinosus, ST)) and on the liver. The animals were supplemented in macro and trace minerals according to usual feeding practices in France in order to theoretically avoid any risk of deficiency. For this reason, cobalt allowances, which are necessary for the ruminal synthesis of vitamin B12, could differ among treatments. The results indicate the following: (1) cobalt allowances varied widely among treatments, from (sub-)deficient to plethoric allowances, influencing vitamin B12 contents of the liver, and muscles (only in case of deficiency), (2) the effects of dietary treatments or of physical exercise were essentially related to differences in cobalt allowances, (3) the oxidative type muscle (RA) showed contents which were double those in glycolytic type muscle (RA 10.8 vs. ST 5.0 ng.g(-1)) and (4) vitamin B12 contents of raw muscles were lower than the values indicated in tables of feed composition for humans for cooked meat (0.5 to 1 vs. 2 to 3 microg.100 g(-1)). PMID:16045893

  4. Ensemble projections of wildfire activity and carbonaceous aerosol concentrations over the western United States in the mid-21st century

    PubMed Central

    Yue, Xu; Mickley, Loretta J.; Logan, Jennifer A.; Kaplan, Jed O.

    2013-01-01

    We estimate future wildfire activity over the western United States during the mid-21st century (2046–2065), based on results from 15 climate models following the A1B scenario. We develop fire prediction models by regressing meteorological variables from the current and previous years together with fire indexes onto observed regional area burned. The regressions explain 0.25–0.60 of the variance in observed annual area burned during 1980–2004, depending on the ecoregion. We also parameterize daily area burned with temperature, precipitation, and relative humidity. This approach explains ~0.5 of the variance in observed area burned over forest ecoregions but shows no predictive capability in the semi-arid regions of Nevada and California. By applying the meteorological fields from 15 climate models to our fire prediction models, we quantify the robustness of our wildfire projections at mid-century. We calculate increases of 24–124% in area burned using regressions and 63–169% with the parameterization. Our projections are most robust in the southwestern desert, where all GCMs predict significant (p<0.05) meteorological changes. For forested ecoregions, more GCMs predict significant increases in future area burned with the parameterization than with the regressions, because the latter approach is sensitive to hydrological variables that show large inter-model variability in the climate projections. The parameterization predicts that the fire season lengthens by 23 days in the warmer and drier climate at mid-century. Using a chemical transport model, we find that wildfire emissions will increase summertime surface organic carbon aerosol over the western United States by 46–70% and black carbon by 20–27% at midcentury, relative to the present day. The pollution is most enhanced during extreme episodes: above the 84th percentile of concentrations, OC increases by ~90% and BC by ~50%, while visibility decreases from 130 km to 100 km in 32 Federal Class 1

  5. Ensemble projections of wildfire activity and carbonaceous aerosol concentrations over the western United States in the mid-21st century

    NASA Astrophysics Data System (ADS)

    Yue, Xu; Mickley, Loretta J.; Logan, Jennifer A.; Kaplan, Jed O.

    2013-10-01

    We estimate future wildfire activity over the western United States during the mid-21st century (2046-2065), based on results from 15 climate models following the A1B scenario. We develop fire prediction models by regressing meteorological variables from the current and previous years together with fire indexes onto observed regional area burned. The regressions explain 0.25-0.60 of the variance in observed annual area burned during 1980-2004, depending on the ecoregion. We also parameterize daily area burned with temperature, precipitation, and relative humidity. This approach explains ˜0.5 of the variance in observed area burned over forest ecoregions but shows no predictive capability in the semi-arid regions of Nevada and California. By applying the meteorological fields from 15 climate models to our fire prediction models, we quantify the robustness of our wildfire projections at midcentury. We calculate increases of 24-124% in area burned using regressions and 63-169% with the parameterization. Our projections are most robust in the southwestern desert, where all GCMs predict significant (p < 0.05) meteorological changes. For forested ecoregions, more GCMs predict significant increases in future area burned with the parameterization than with the regressions, because the latter approach is sensitive to hydrological variables that show large inter-model variability in the climate projections. The parameterization predicts that the fire season lengthens by 23 days in the warmer and drier climate at midcentury. Using a chemical transport model, we find that wildfire emissions will increase summertime surface organic carbon aerosol over the western United States by 46-70% and black carbon by 20-27% at midcentury, relative to the present day. The pollution is most enhanced during extreme episodes: above the 84th percentile of concentrations, OC increases by ˜90% and BC by ˜50%, while visibility decreases from 130 km to 100 km in 32 Federal Class 1 areas in

  6. Ensemble projections of wildfire activity and carbonaceous aerosol concentrations over the western United States in the mid-21st century.

    PubMed

    Yue, Xu; Mickley, Loretta J; Logan, Jennifer A; Kaplan, Jed O

    2013-10-01

    We estimate future wildfire activity over the western United States during the mid-21(st) century (2046-2065), based on results from 15 climate models following the A1B scenario. We develop fire prediction models by regressing meteorological variables from the current and previous years together with fire indexes onto observed regional area burned. The regressions explain 0.25-0.60 of the variance in observed annual area burned during 1980-2004, depending on the ecoregion. We also parameterize daily area burned with temperature, precipitation, and relative humidity. This approach explains ~0.5 of the variance in observed area burned over forest ecoregions but shows no predictive capability in the semi-arid regions of Nevada and California. By applying the meteorological fields from 15 climate models to our fire prediction models, we quantify the robustness of our wildfire projections at mid-century. We calculate increases of 24-124% in area burned using regressions and 63-169% with the parameterization. Our projections are most robust in the southwestern desert, where all GCMs predict significant (p<0.05) meteorological changes. For forested ecoregions, more GCMs predict significant increases in future area burned with the parameterization than with the regressions, because the latter approach is sensitive to hydrological variables that show large inter-model variability in the climate projections. The parameterization predicts that the fire season lengthens by 23 days in the warmer and drier climate at mid-century. Using a chemical transport model, we find that wildfire emissions will increase summertime surface organic carbon aerosol over the western United States by 46-70% and black carbon by 20-27% at midcentury, relative to the present day. The pollution is most enhanced during extreme episodes: above the 84(th) percentile of concentrations, OC increases by ~90% and BC by ~50%, while visibility decreases from 130 km to 100 km in 32 Federal Class 1 areas in

  7. Frequency-dependent impedance spectroscopy on the 0.925(Bi0.5Na0.40K0.10)TiO3-0.075(Ba0.70Sr0.30)TiO3 ceramic

    NASA Astrophysics Data System (ADS)

    Ullah, Amir; Rahman, Muneeb-ur; Iqbal, Muhammad Javid; Ahn, Chang Won; Kim, Ill Won; Ullah, Aman

    2016-06-01

    The electrical properties of the 0.925(Bi0.5(Na0.40K0.10)TiO3-0.075(Ba0.70Sr0.30)TiO3 (0.925BNKT-0.075BST) ceramic were investigated by using AC impedance spectroscopy over a wide range of frequencies (10 -2 ~ 105 Hz). The X-ray diffraction patterns confirmed the formation of a single-phase compound. A single semicircular arc in the impedance spectrum indicates that the main contribution of the bulk resistance ( R b ) were due to grain effects, with Rb decreasing with increasing temperature. The conductivity of the ceramics increased with increasing temperatu