Effects of solar eclipse on the electrodynamical processes of the equatorial ionosphere: a case study during 11 August 1999 dusk time total solar eclipse over India

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R. Sridharan

Full Text Available The effects on the electrodynamics of the equatorial E- and F-regions of the ionosphere, due to the occurrence of the solar eclipse during sunset hours on 11 August 1999, were investigated in a unique observational campaign involving ground based ionosondes, VHF and HF radars from the equatorial location of Trivandrum (8.5° N; 77° E; dip lat. 0.5° N, India. The study revealed the nature of changes brought about by the eclipse in the evening time E- and F-regions in terms of (i the sudden intensification of a weak blanketing E_S-layer and the associated large enhancement of the VHF backscattered returns, (ii significant increase in h' F immediately following the eclipse and (iii distinctly different spatial and temporal structures in the spread-F irregularity drift velocities as observed by the HF radar. The significantly large enhancement of the backscattered returns from the E-region coincident with the onset of the eclipse is attributed to the generation of steep electron density gradients associated with the blanketing E_S , possibly triggered by the eclipse phenomena. The increase in F-region base height immediately after the eclipse is explained as due to the reduction in the conductivity of the conjugate E-region in the path of totality connected to the F-region over the equator along the magnetic field lines, and this, with the peculiar local and regional conditions, seems to have reduced the E-region loading of the F-region dynamo, resulting in a larger post sunset F-region height (h' F rise. These aspects of E-and F-region behaviour on the eclipse day are discussed in relation to those observed on the control day.

Key words. Ionosphere (electric fields and currents; equatorial ionosphere; ionospheric irregularities

Gestational diabetes mellitus prevalence in Maela refugee camp on the Thai–Myanmar Border: a clinical report

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Mary Ellen Gilder

2014-05-01

Full Text Available Background: Individuals in conflict-affected areas rarely get appropriate care for chronic or non-infectious diseases. The prevalence of gestational diabetes mellitus (GDM is increasing worldwide, and new evidence shows conclusively that the negative effects of hyperglycemia occur even at mild glucose elevations and that these negative effects can be attenuated by treatment. Scientific literature on gestational diabetes in refugee camp settings is critically limited. Methods: A 75 g 2-hour glucose tolerance test was administered to 228 women attending the antenatal care (ANC clinic in Maela refugee camp on the Thai–Myanmar border. Prevalence of GDM was determined using the HAPO trial cut-offs [≥92 mg/dL (fasting,≥180 (1 hour, and≥153 (2 hour] and the WHO criteria [≥126 mg/dL (fasting, and 140 mg/dL (2 hour]. Results: From July 2011 to March 2012, the prevalence of GDM was 10.1% [95% confidence interval (CI: 6.2–14.0] when the cut-off determined by the HAPO trial was applied. Applying the older WHO criteria yielded a prevalence of 6.6% (95% CI 3.3–9.8. Age, parity, and BMI emerged as characteristics that may be significantly associated with GDM in this population. Other risk factors that are commonly used in screening guidelines were not applicable in this diabetes-naïve population. Discussion: The prevalence of GDM is lower in this population compared with other populations, but still complicates 10% of pregnancies. New evidence regarding gestational diabetes raises new dilemmas for healthcare providers in resource-poor settings. Efforts to identify and treat patients at risk for adverse outcomes need to be balanced with awareness of the risks and burdens associated with over diagnosis and unnecessary interventions. Screening approaches based on risk factors or using higher cut-off values may help minimize this burden and identify those most likely to benefit from intervention.

The role of inflammatory pathway genetic variation on maternal metabolic phenotypes during pregnancy.

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Margrit Urbanek

Full Text Available Since mediators of inflammation are associated with insulin resistance, and the risk of developing diabetes mellitus and gestational diabetes, we hypothesized that genetic variation in members of the inflammatory gene pathway impact glucose levels and related phenotypes in pregnancy. We evaluated this hypothesis by testing for association between genetic variants in 31 inflammatory pathway genes in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO cohort, a large multiethnic multicenter study designed to address the impact of glycemia less than overt diabetes on pregnancy outcome.Fasting, 1-hour, and 2-hour glucose, fasting and 1-hour C-peptide, and HbA1c levels were measured in blood samples obtained from HAPO participants during an oral glucose tolerance test at 24-32 weeks gestation. We tested for association between 458 SNPs mapping to 31 genes in the inflammatory pathway and metabolic phenotypes in 3836 European ancestry and 1713 Thai pregnant women. The strongest evidence for association was observed with TNF alpha and HbA1c (rs1052248; 0.04% increase per allele C; p-value = 4.4×10(-5, RETN and fasting plasma glucose (rs1423096; 0.7 mg/dl decrease per allele A; p-value = 1.1×10(-4, IL8 and 1 hr plasma glucose (rs2886920; 2.6 mg/dl decrease per allele T; p-value = 1.3×10(-4, ADIPOR2 and fasting C-peptide (rs2041139; 0.55 ug/L decrease per allele A; p-value = 1.4×10(-4, LEPR and 1-hour C-peptide (rs1171278; 0.62 ug/L decrease per allele T; p-value = 2.4×10(-4, and IL6 and 1-hour plasma glucose (rs6954897; -2.29 mg/dl decrease per allele G, p-value = 4.3×10(-4.Based on the genes surveyed in this study the inflammatory pathway is unlikely to have a strong impact on maternal metabolic phenotypes in pregnancy although variation in individual members of the pathway (e.g. RETN, IL8, ADIPOR2, LEPR, IL6, and TNF alpha, may contribute to metabolic phenotypes in pregnant women.

Negative responses of Collembola in a forest soil (Alptal, Switzerland) under experimentally increased N deposition

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Xu Guoliang, E-mail: xugl@scbg.ac.c [Institute of Ecology, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650 (China); Schleppi, Patrick; Li Maihe [Swiss Federal Institute for Forest, Snow and Landscape Research, CH-8903 Birmensdorf (Switzerland); Fu Shenglei, E-mail: sfu@scib.ac.c [Institute of Ecology, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650 (China)

2009-07-15

The response of specific groups of organisms, like Collembola to atmospheric nitrogen (N) deposition is still scarcely known. We investigated the Collembola community in a subalpine forest (Alptal, Switzerland) as subjected for 12 years to an experimentally increased N deposition (+25 on top of ambient 12 kg N ha{sup -1} year{sup -1}). In the 0-5 cm soil layer, there was a tendency of total Collembola densities to be lower in N-treated than in control plots. The density of Isotomiella minor, the most abundant species, was significantly reduced by the N addition. A tendency of lower Collembola group richness was observed in N-treated plots. The Density-Group index (d{sub DG}) showed a significant reduction of community diversity, but the Shannon-Wiener index (H') was not significantly affected by the N addition. The Collembola community can be considered as a bioindicator of N inputs exceeding the biological needs, namely, soil N saturation. - Collembola community, which was significantly affected by a long-term N addition experiment, can be considered as a bioindicator of N saturation.

HAPO Plant and capital equipment budget for FY 1966 and revision of budget for FY 1965 equipment not related to construction projects

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McDonald, J.E.

1964-05-12

This document is divided into: byproduct horizontal control rod system (5 reactors); high-speed scanning-effluent temperature monitoring system (KE reactor); improved reactor gas system (100-KE & KW); safety circuit system modifications (5 reactors); alternate process hot die sizing, 313 Building 300 Area; button line equipment (234-5 Building); in-tank waste solidification (3rd unit); and misc. minor equipment projects.

Assessment of macrofauna around Tarapur Atomic Power Station (TAPS), Maharashtra, India

International Nuclear Information System (INIS)

Kubal, Priti; Ambekar, Ajit; Prakash, Chandra; Sawant, Paramita B.; Pal, Asim K.; Lakra, W.S.; Baburajan, A.

2015-01-01

A study was carried out to observe the macrofaunal habitation in the coastal area of India's first commercial atomic power station at Tarapur, Maharashtra. Mostly macrobenthos are sedentary as well as sessile in nature; therefore, they are used as indicator organism to monitor health of marine ecosystem. The faunal record observed consisted of 25 groups with 16 different polychaete families dominated by nereidae, capitellidae and spionidae. Shannon wiener index (H') was highest at Varor for faunal groups (2.07) and polychaete families (2.89) and lowest at anthropogenically stressed Uchheli (faunal group -0.77 and polychaete family 1.94). These findings were further supported by dendrogram. Margalef's species richness was highest at Varor (fauna -1.93 and polychaete family -1.61) and lowest at Nandgoan (fauna-1.00 and polychaete family - 0.74) due to dominance of environmental bioindicators, polychaete (nereidae). Along with these observations, hydro-sedimentological parameters revealed comprehensive picture of community structure of macrobenthos and polychaetes families. The elevated water temperature was noticed at TAPS 3 and 4 (30.1 °C) which is under permissible limit (26-28°C ±7) accompanied by pH (7.0). Dissolved oxygen was lowest at Uchheli (4.1mgl -1 ) and maximum was observed at TAPS 1 and 2 area (7.5mgl -1 ). (author)

Aquatic studies of Gable Mountain Pond

International Nuclear Information System (INIS)

Cushing, C.E.; Watson, D.G.

1974-12-01

Studies of the biotic and abiotic components of the Gable Mountain Pond (HAPO cooling water disposal pond) ecosystem were undertaken to determine if there was a potential problem for off-site transfer of radioactivity to man originating with the aquatic food web. Most of the 137 Cs in the pond is associated with the sediments which are probably the main source of 137 Cs for uptake by the biota. Generally, highest concentrations of 137 Cs and other radioisotopes were found in the upper two inches of sediments in the northwest end of the pond and in the deeper areas along the long-axis of the pond. Native goldfish had maximum and average 137 Cs concentrations of about 340 and 170 pCi/g dry wt, respectively. Algae, macrophytes, and detritus comprised the main food items of the goldfish, and the 137 Cs levels in the plants were usually higher than the 137 Cs concentration in the fish. The 137 Cs concentrations of wild experimental ducks restricted to Gable Mountain Pond were approximately the same as resident coots, but significantly higher than transient wild ducks. Neither the goldfish nor the waterfowl inhabiting the pond attained concentrations of 137 Cs exceeding acceptable limits. Sediment, however, could be a source of high concentrations of radioactivity or radioactive contamination concern if the concentration of radiocontaminants increased and/or the pond dries up, and the contaminated sediments become windborne. (U.S.)

Preparation of polypyrrole/ferrocyanide films modified carbon paste electrode and its application on the electrocatalytic determination of ascorbic acid

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Raoof, Jahan-Bakhsh; Ojani, Reza; Rashid-Nadimi, Sahar

2004-01-15

Functionalized polypyrrole film were prepared by incorporation of (Fe(CN){sub 6}){sup 4-} as doping anion, during the electropolymerization of pyrrole onto a carbon paste electrode (CPE) in aqueous solution by using potentiostatic method. The electrochemical behavior of the (Fe(CN){sub 6}){sup 3-}/(Fe(CN){sub 6}){sup 4-} redox couple in polypyrrole was studied by cyclic voltammetry and double step potential chronoamperometry methods. In this study, an obvious surface redox reaction was observed and dependence of this reaction on the solution pH was illustrated. The electrocatalytic ability of polypyrrole/ferrocyanide films modified carbon paste electrode (Ppy/FCNMCPEs) was demonstrated by oxidation of ascorbic acid. It has been found that under optimum condition (pH 7.00), the oxidation of ascorbic acid at the surface of such electrode occurs at a potential about 540 mV less positive than unmodified carbon paste electrode. The kinetic parameters such as electron transfer coefficient, {alpha} and catalytic reaction rate constant, k{sub h}', were also determined by using various electrochemical approaches. The catalytic oxidation peak current showed a linear dependent on the ascorbic acid concentration and a linear calibration curve was obtained in the range of 4.5x10{sup -4} to 9.62x10{sup -3} M of ascorbic acid with a correlation coefficient of 0.9999. The detection limit (2{sigma}) was determined as 5.82x10{sup -5} M.

Parametric assessments on hydrogenic species transport in CVD-diamond vacuum windows used in ITER ECRH

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Moreno, C.; Sedano, L.A.; Fernandez, A. [EURATOM-CIEMAT Association, Madrid (Spain)

2007-07-01

Insulators used as H and CD and Diagnostic vacuum windows (VW) in ITER may become modified by surface intake and bulk transport of hydrogenic species. VW, operating under severe radiation levels, have a primary safety role as tritium confinement barriers. Ionizing radiation enhances the (H') uptake and release at surfaces and diffusion rates in the bulk. Radiation damage modifies the material's bulk trapped inventories by increasing steady state trapping centre concentrations. An experimental programme is ongoing at CIEMAT, to quantify radiation effects on H transport characteristics and also the possible impact on the VW. The reference material for ECRH VW is CVD diamond. As a parallel activity, parametric transport assessments are being made in order to obtain a wide evaluation of permeation fluxes, ranges, and soluted/trapped inventories in CVD diamond. Transport models have been developed based on extended capabilities of finite differences integrator tool TMAP7. Special attention is paid to radiation parameters defining inputs acting on transport magnitudes. These inputs have been analysed by using ionizing/damage radiation transport tools such as MCNPX/SRIM. VW operational scenarios are discussed with special attention being paid to the ITER design assumptions for the values of H-species source terms (neutrals and implanted) in the ECRH system. The available material transport database with and without radiation is discussed and taken as reference for this parametric exercise. Permeation fluxes through base materials are shown to be below DRG limits established for ITER. (orig.)

Inhibition of marine algal photosynthesis by heavy metals

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Overnell, J.

1976-12-03

A total of ninety phytoplankton species was recorded from June 1972 to May 1973 in samples taken weekly at Seal Beach, California. The study area was located in the vicinity of the mouth of the San Gabriel River, which is used as a site of discharge for heated effluents by two electric power plants and as a flood control channel by Los Angeles County. On a yearly basis, the two dominant algal groups were diatoms (forty-six species) and dinoflagellates (thirty-six species), accounting respectively for 64 percent and 30 percent of the total cell number, and for 20 percent and 79 percent of the total cell volume. The average phytoplankton concentration throughout the year was 180,000 cells l/sup -1/. A dinoflagellate bloom was observed in August between the two major peaks of diatoms which occurred during June--July and in late September. The five most common species (in order), Rhizosolenia delicatula, Chaetoceros curvisetus, Prorocentrum micans, Ceratium furca and Gymnodinium simplex, were present in more than 50 percent of the samples. The species diversity index (H') remained relatively stable during the year, showing no distinct seasonal pattern. Three interconnected associations of species were distinguished by x/sup 2/ analysis. The major group, composed mainly of dinoflagellates, was correlated with warm water conditions at Seal Beach. The other groups occurred at various times during the year, irrespective of seasonal variations, suggesting a possible mutualistic relationship between the species involved.

Mensuration of equivalent dose with personal dosemeters and instruments of radiological protection in the new operative quantities ICRU, for external fields of beta radiation. Part II. I study of the angular response of personal dosemeters TLD-100 in secondary patron fields of beta radiation ({sup 90}Sr / {sup 90}Y); Medicion de dosis equivalente con dosimetros personales e instrumentos de proteccion radiologica en las nuevas magnitudes operativas ICRU, para campos de radiacion beta externos. Parte II. Estudio de la respuesta angular de dosimetros personales TLD-100 en campos patrones secundarios de radiacion beta ({sup 90}Sr/{sup 90}Y)

Energy Technology Data Exchange (ETDEWEB)

Alvarez R, J.T. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

1994-01-15

The objective of this work is to carry out one of the possible ones test type for personal dosemeters TLD, under the recomendations of the ICRU 39, ICRU 43 and the draft of the norm ISO 6980,(1992), with the purpose of verifying the capacity of these detectors to carry out the operative unit: H' (0.07;{alpha}). Since H' (O. 07;{alpha}) this defined one in an expanded field, one of these tests type consist on determining the angular response of these detectors. 20 personal dosemeters TLD-100 was used, (card marks: Harshaw, Model: G-1, with two glasses of TLD-100 absorbed in teflon; the portadosemeters has two windows, a free one and another with a filter of Pb of 171.0 mg cm{sup -2}); these dosemeters they were previously selected, [to see, {sup S}tudy of the Homogeneity of the response of Personal Dosemeters (Cards G-l, TLD-100) in Radiation of Countrysides of {sup 60}Co{sup ,} J.T. Alvarez R. Technician Report GSR/IT/0001/94].The irradiations to effectued in secondary countryside of radiation beta of {sup 90}Sr/{sup 90}Y. The study was undertaken by means of an experimental design of blocks random that contemplate the following variables: intensity of the radiation source, (1850 MBq and 74 MBq); position of irradiation, (four positions); incidence of angle of the radiation (0, 15, 30, 45, 60 and 75 grades) and the absorbed dose in air, (0.005, 0.010, 0.020, 0.050 and 0.100 Gy). Then null hypothesis it was to suppose that there was not difference among the stockings of each treatment, to used the statistical of Duncan to carry out tests of stockings at a level of significance of 5%.These tests of stockings throw the following results in those variables of the experimental design: The irradiations carried out so much with the source pattern secondary of {sup 90}Sr/{sup 90}Y of 1850 MBq and of 74 MBq, they are equivalent reason why they can be used indistinctly. The responses of each one of the glasses of the card are strongly anisotropic for each glass

Environmental Survey at Ormen Lange, June 2009

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Mannvik, Hans-Petter; Wasbotten, Ingar Halvorsen; Cochrane, Sabine

2010-07-01

An environmental monitoring survey was carried out at Ormen Lange in Region V on behalf of Norske Shell. The samples were collected at 19 stations by use of a 0.25 m{sub 2} box corer and carried out in connection with the field work in Region VI. The station depths varied between 823 and 925 m. The sediments at Ormen Lange are classified as silt with a high amount of pelite (> 90 %) and TOM (> 9 %). The amount of pelite is higher than that found in the baseline survey in 2004 at all stations. Whether this is a result of changes in sediment composition or a difference in analytical methods used is not known. With the exception of station OL-01 and OL-09, where a small increase has occurred, the amount of TOM has decreased at the stations since 2004. The concentrations of hydrocarbons and metals in the sediments at Template D, can be regarded as the natural background level for these parameters. The average amount of THC in the sediments around Template D is 11.7 +- 1.8 mg/kg in this base line survey. The average level of THC at template A and B was at the same level in the base line survey in 2004, 9.7 +- 0.6 mg/kg. In the present survey the average amount of THC in the sediments at Template A and B has increased to 17.0 +- 3.9 mg/kg. 11 of 14 stations at Template A and B have slightly elevated levels of barium and zinc in the sediments and sediments at three stations are elevated with mercury. In the present survey the mollusks dominates the fauna at Ormen Lange. The number of individuals at the stations (0.4 m{sub 2}) is high (1553 - 2833), while the number of taxa is relatively low (51 - 73), resulting in a very low diversity (H' 2.4 - 3.3). This is due to the over dominance by two mussels (Thyasira minuta and T. equalis) at all stations. However, the dominant species registered are known to be abundant in sediment with high amount of pelite and organic material. Due to the different sampling strategy and area, a direct comparison with the baseline survey is

Fault of the correction factor for pressure and temperature k{sub PT} in the atmospheric conditions of Dosimetric Calibration Lab. - LSCD of ININ - Mexico; Falla del factor de correcion por presion y temperatura k{sub PT} a las condiciones atmosfericas del LSCD-ININ-Mexico

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Alvarez R, Jose T.; Jesus Cejudo, A.; La Cruz H., Daniel de; Tovar M, Victor M., E-mail: trinidad.alvarez@inin.gob.mx, E-mail: jesus.cejudo@inin.gob.mx, E-mail: daniel.delacruz@inin.gob.mx, E-mail: victor.tovar@inin.gob.mx [Instituto Nacional de Investigaciones Nucleares (LSCD/ININ), Ocoyoacac (Mexico). Laboratorio Secundario de Calibracion Dosimetrica

2013-07-01

The realization of the operational quantities H*, Hp y/0 H'(0.07) for estimating the effective dose E, usually is done by measuring the air kerma Ka air within the field of ionizing radiation of interest and was subsequently applied appropriate conversion factors for both the quality of radiation and the operational quantity of interest. However, the SSDL in performing the Ka to environmental conditions of ININ (3000 m above sea level, P ∼ 710 hPa) with ionization chambers has found that the pressure correction factor and kPT temperature is not sufficient to correct the change in air density. Indeed, in the case of {sup 60}Co the discrepancy between the measurement of a primary standard graphite walls Ka (BEV CC01 be 131) and a side of the plastic walls (Exradin A12) is on the order of 0.4% for the case of the RX BIPM qualities to 100,135, 180 and 250 kV. It was found that for a camera model 30001 PTW (PMMA graphite wall) is needed an additional correction factor k PT ranging from 0.4% to 1.5%, correction factor calculated by MC simulation. For Sk of {sup 125}I brachytherapy sources was given an additional correction lower in 11% compared to conventional k{sub PT} value measured with a well chamber Standard Imaging HDR 1000 plus. Finally, it is in the process of studying the behavior of this additional correction factor to the case of {sup 137}Cs.

Top-down holographic G-structure glueball spectroscopy at (N)LO in N and finite coupling

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Sil, Karunava; Yadav, Vikas; Misra, Aalok [Indian Institute of Technology, Department of Physics, Roorkee, Uttaranchal (India)

2017-06-15

The top-down type IIB holographic dual of large-N thermal QCD as constructed in Mia et al. (Nucl Phys B 839:187, 2010) involving a fluxed resolved warped deformed conifold, its delocalized type IIA Strominger-Yau-Zaslow-mirror (SYZ-mirror) as well as its M-theory uplift constructed in Dhuria and Misra (JHEP 1311:001, 2013) - both in the finite coupling g{sub s} h}') on the solutions to the equations of motion on the other hand. We find that the former technique produces results closer to the lattice results. We also discuss the r{sub h} = 0 limits of all calculations. In this context we also calculate the 0{sup ++}, 0{sup --}, 1{sup ++}, 2{sup ++} glueball masses up to Next to Leading Order (NLO) in N and find a (g{sub s}M{sup 2})/(N)(g{sub s}N{sub f})-suppression similar to and further validating semi-universality of NLO corrections to transport coefficients, observed in Sil and Misra (Eur Phys J C 76(11):618, 2016). (orig.)